Sample records for 7-year histogram 1985-1991

  1. Changes in Energy Intensity 1985-1991

    Annual Energy Outlook 2013 [U.S. Energy Information Administration (EIA)]

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742 33 111 1,613 122 40Coal Stocks at CommercialDecadeReservesYear JanDecade Year-0 Year-1 Year-2

  2. Node Histogram vs. Edge Histogram:Node Histogram vs. Edge Histogram: A Comparison of Probabilistic ModelA Comparison of Probabilistic Model--BuildingBuilding

    E-Print Network [OSTI]

    Tsutsui, Shigeyoshi

    to PMBGAsPMBGAs inin permutationpermutation domainsdomains ­­ Edge Histogram Sampling Algorithm (EHBSA another approach toWe propose another approach to PMBGAsPMBGAs inin permutationpermutation domainsdomains

  3. Intensity Histogram CMOS Image Sensor for Adaptive Optics

    E-Print Network [OSTI]

    Cauwenberghs, Gert

    Intensity Histogram CMOS Image Sensor for Adaptive Optics Yu M. Chi, Gary Carhart , Mikhail AAODisturbanceSource Update/Optimize Fig. 1. Intended real-time optical control application. The sensor computes histogram of Bioengineering University of California, San Diego La Jolla, CA 92093 Intelligent Optics Lab U.S. Army Research

  4. Representing Topological Relationships between Complex Regions by F-Histograms

    E-Print Network [OSTI]

    Matsakis, Pascal

    Representing Topological Relationships between Complex Regions by F-Histograms Lukasz Wawrzyniak between two regions in terms of the thirteen Allen relations. An index to measure the complexity Work in the modeling of topological relationships often relies on an extension into the spatial domain

  5. F-Histograms and Fuzzy Directional Spatial Relations Pascal Matsakis

    E-Print Network [OSTI]

    Matsakis, Pascal

    , pattern recognition, scene analysis, fuzzy relations, fuzzy sets. 1. Introduction Knowing how to apprehend the spatial organization of 2-D objects is essential to computer vision (for pattern recognition, imageF-Histograms and Fuzzy Directional Spatial Relations Pascal Matsakis 1 , James M. Keller 1

  6. Selecting the Number of Bins in a Histogram: A Decision Theoretic Approach

    E-Print Network [OSTI]

    Meeden, Glen

    Running Title Number of Bins in a Histogram ABSTRACT In this note we consider the problem of, given a sample, selecting the number of bins in a histogram. A loss function is introduced which reflects a loss function which incorporates the idea that smoother densities require less bins in their histogram

  7. Microcanonical thermostatistics analysis without histograms: cumulative distribution and Bayesian approaches

    E-Print Network [OSTI]

    Alves, Nelson A; Rizzi, Leandro G

    2015-01-01T23:59:59.000Z

    Microcanonical thermostatistics analysis has become an important tool to reveal essential aspects of phase transitions in complex systems. An efficient way to estimate the microcanonical inverse temperature $\\beta(E)$ and the microcanonical entropy $S(E)$ is achieved with the statistical temperature weighted histogram analysis method (ST-WHAM). The strength of this method lies on its flexibility, as it can be used to analyse data produced by algorithms with generalised sampling weights. However, for any sampling weight, ST-WHAM requires the calculation of derivatives of energy histograms $H(E)$, which leads to non-trivial and tedious binning tasks for models with continuous energy spectrum such as those for biomolecular and colloidal systems. Here, we discuss two alternative methods that avoid the need for such energy binning to obtain continuous estimates for $H(E)$ in order to evaluate $\\beta(E)$ by using ST-WHAM: (i) a series expansion to estimate probability densities from the empirical cumulative distrib...

  8. Improving Data Locality Using Dynamic Page Migration based on Memory Access Histograms

    E-Print Network [OSTI]

    Stamatakis, Alexandros

    Improving Data Locality Using Dynamic Page Migration based on Memory Access Histograms Jie Tao user­level page migration. It uses memory access histograms gathered by hardware monitors to make applications show the potential for a significant gain in speedup. In addition, a graphical user inter­ face

  9. Making an Energy Histogram Using Pierre Auger Observatory Surface Detector Data A histogram is essentially a graphical representation of the frequency or distribution of a variable over specific intervals

    E-Print Network [OSTI]

    Making an Energy Histogram Using Pierre Auger Observatory Surface Detector Data Histogram A histogram is essentially a graphical representation of the frequency or distribution of a variable over energies. Before you start you should know that: o This set of instructions only assumes a very minimal

  10. A Flat Histogram Method for Computing the Density of States of Combinatorial Stefano Ermon, Carla Gomes, Bart Selman

    E-Print Network [OSTI]

    Keinan, Alon

    A Flat Histogram Method for Computing the Density of States of Combinatorial Problems Stefano Ermon of both SAT, MAX- SAT and model counting. We propose a novel Markov Chain Monte Carlo al- gorithm

  11. Outrunning major weight gain: a prospective study of 8,340consistent runners during 7 years of follow-up

    SciTech Connect (OSTI)

    Williams, Paul T.

    2006-01-06T23:59:59.000Z

    Background: Body weight increases with aging. Short-term,longitudinal exercise training studies suggest that increasing exerciseproduces acute weight loss, but it is not clear if the maintenance oflong-term, vigorous exercise attenuates age-related weight gain inproportion to the exercise dose. Methods: Prospective study of 6,119 maleand 2,221 female runners whose running distance changed less than 5 km/wkbetween their baseline and follow-up survey 7 years later. Results: Onaverage, men who ran modest (0-24 km/wk), intermediate (24-48 km/wk) orprolonged distances (>_48 km/wk) all gained weight throughage 64,however, those who ran ?48 km/wk had one-half the average annual weightgain of those who ran<24 km/wk. Age-related weight gain, and itsreduction by running, were both greater in younger than older men. Incontrast, men s gain in waist circumference with age, and its reductionby running, were the same in older and younger men. Women increased theirbody weight and waist and hip circumferences over time, regardless ofage, which was also reduced in proportion to running distance. In bothsexes, running did not attenuate weight gain uniformly, but ratherdisproportionately prevented more extreme increases. Conclusion: Men andwomen who remain vigorously active gain less weight as they age and thereduction is in proportion to the exercise dose.

  12. The Confined-Deconfined Interface Tension in Quenched QCD using the Histogram Method

    E-Print Network [OSTI]

    B. Grossmann; M. L. Laursen

    1993-01-28T23:59:59.000Z

    We present results for the confinement-deconfinement interface tension $\\sigma_{cd}$ of quenched QCD. They were obtained by applying Binder's histogram method to lattices of size $L^2\\times L_z\\times L_t$ for $L_t=2$ and $L=8,10,12\\mbox{ and }14$ and various $L_z\\in [L,\\, 4\\, L]$. The use of a multicanonical algorithm and rectangular geometries have turned out to be crucial for the numerical studies. We also give an estimate for $\\sigma_{cd}$ at $L_t=4$ using published data.

  13. Coral Vision 1.0 uses histograms on hue trained over the positive and negative user clicks.

    E-Print Network [OSTI]

    Stough, Joshua

    Coral Vision 1.0 uses histograms on hue trained over the positive and negative user clicks. The initial pixel-wise decision is culled and smoothed using image morphological operations Coral Vision: Software for Improving Efficiency in Coral Monitoring Cory L. Walker, Joshua V. Stough Lisa Greer

  14. High-Dose-Rate Brachytherapy and External-Beam Radiotherapy for Hormone-Naieve Low- and Intermediate-Risk Prostate Cancer: A 7-Year Experience

    SciTech Connect (OSTI)

    Aluwini, Shafak, E-mail: s.aluwini@erasmusmc.nl [Department of Radiation Oncology, Erasmus MC, Daniel den Hoed Cancer Center, Rotterdam (Netherlands)] [Department of Radiation Oncology, Erasmus MC, Daniel den Hoed Cancer Center, Rotterdam (Netherlands); Rooij, Peter H. van [Department of Radiation Oncology, Erasmus MC, Daniel den Hoed Cancer Center, Rotterdam (Netherlands)] [Department of Radiation Oncology, Erasmus MC, Daniel den Hoed Cancer Center, Rotterdam (Netherlands); Kirkels, Wim J. [Department of Urology, Erasmus MC, Daniel den Hoed Cancer Center, Rotterdam (Netherlands)] [Department of Urology, Erasmus MC, Daniel den Hoed Cancer Center, Rotterdam (Netherlands); Jansen, Peter P.; Praag, John O. [Department of Radiation Oncology, Erasmus MC, Daniel den Hoed Cancer Center, Rotterdam (Netherlands)] [Department of Radiation Oncology, Erasmus MC, Daniel den Hoed Cancer Center, Rotterdam (Netherlands); Bangma, Chris H. [Department of Urology, Erasmus MC, Daniel den Hoed Cancer Center, Rotterdam (Netherlands)] [Department of Urology, Erasmus MC, Daniel den Hoed Cancer Center, Rotterdam (Netherlands); Kolkman-Deurloo, Inger-Karine K. [Department of Radiation Oncology, Erasmus MC, Daniel den Hoed Cancer Center, Rotterdam (Netherlands)] [Department of Radiation Oncology, Erasmus MC, Daniel den Hoed Cancer Center, Rotterdam (Netherlands)

    2012-08-01T23:59:59.000Z

    Purpose: To report clinical outcomes and early and late complications in 264 hormone-naieve patients with low- and intermediate-risk prostate cancer treated with high-dose-rate brachytherapy (HDR-BT) in combination with external-beam radiotherapy (EBRT). Methods and Materials: Between February 2000 and July 2007, 264 patients underwent HDR-BT in combination with EBRT as a treatment for their low- to intermediate-risk prostate cancer. The HDR-BT was performed using ultrasound-based implantation. The total HDR-BT dose was 18 Gy in 3 fractions within 24 h, with a 6-h minimum interval. The EBRT started 2 weeks after HDR-BT and was delivered in 25 fractions of 1.8 Gy to 45 Gy within 5 weeks. Results: After a mean follow-up of 74.5 months, 4 patients (1.5%) showed prostate-specific antigen progression according to the American Society for Radiation Oncology definition and 8 patients (3%) according to the Phoenix definition. A biopsy-proven local recurrence was registered in 1 patient (0.4%), and clinical progression (bone metastases) was documented in 2 patients (0.7%). Seven-year actuarial freedom from biochemical failure was 97%, and 7-year disease-specific survival and overall survival were 100% and 91%, respectively. Toxicities were comparable to other series. Conclusions: Treatment with interstitial HDR-BT plus EBRT shows a low incidence of late complications and a favorable oncologic outcome after 7 years follow-up.

  15. Nanothermodynamics of large iron clusters by means of a flat histogram Monte Carlo method

    SciTech Connect (OSTI)

    Basire, M.; Soudan, J.-M.; Angelié, C., E-mail: christian.angelie@cea.fr [Laboratoire Francis Perrin, CNRS-URA 2453, CEA/DSM/IRAMIS/LIDyL, F-91191 Gif-sur-Yvette Cedex (France)

    2014-09-14T23:59:59.000Z

    The thermodynamics of iron clusters of various sizes, from 76 to 2452 atoms, typical of the catalyst particles used for carbon nanotubes growth, has been explored by a flat histogram Monte Carlo (MC) algorithm (called the ?-mapping), developed by Soudan et al. [J. Chem. Phys. 135, 144109 (2011), Paper I]. This method provides the classical density of states, g{sub p}(E{sub p}) in the configurational space, in terms of the potential energy of the system, with good and well controlled convergence properties, particularly in the melting phase transition zone which is of interest in this work. To describe the system, an iron potential has been implemented, called “corrected EAM” (cEAM), which approximates the MEAM potential of Lee et al. [Phys. Rev. B 64, 184102 (2001)] with an accuracy better than 3 meV/at, and a five times larger computational speed. The main simplification concerns the angular dependence of the potential, with a small impact on accuracy, while the screening coefficients S{sub ij} are exactly computed with a fast algorithm. With this potential, ergodic explorations of the clusters can be performed efficiently in a reasonable computing time, at least in the upper half of the solid zone and above. Problems of ergodicity exist in the lower half of the solid zone but routes to overcome them are discussed. The solid-liquid (melting) phase transition temperature T{sub m} is plotted in terms of the cluster atom number N{sub at}. The standard N{sub at}{sup ?1/3} linear dependence (Pawlow law) is observed for N{sub at} >300, allowing an extrapolation up to the bulk metal at 1940 ±50 K. For N{sub at} <150, a strong divergence is observed compared to the Pawlow law. The melting transition, which begins at the surface, is stated by a Lindemann-Berry index and an atomic density analysis. Several new features are obtained for the thermodynamics of cEAM clusters, compared to the Rydberg pair potential clusters studied in Paper I.

  16. Elucidating the effects of adsorbent flexibility on fluid adsorption using simple models and flat-histogram sampling methods

    SciTech Connect (OSTI)

    Shen, Vincent K., E-mail: vincent.shen@nist.gov; Siderius, Daniel W. [Chemical Informatics Research Group, Chemical Sciences Division, National Institute of Standards and Technology, Gaithersburg, Maryland 20899-8380 (United States)

    2014-06-28T23:59:59.000Z

    Using flat-histogram Monte Carlo methods, we investigate the adsorptive behavior of the square-well fluid in two simple slit-pore-like models intended to capture fundamental characteristics of flexible adsorbent materials. Both models require as input thermodynamic information about the flexible adsorbent material itself. An important component of this work involves formulating the flexible pore models in the appropriate thermodynamic (statistical mechanical) ensembles, namely, the osmotic ensemble and a variant of the grand-canonical ensemble. Two-dimensional probability distributions, which are calculated using flat-histogram methods, provide the information necessary to determine adsorption thermodynamics. For example, we are able to determine precisely adsorption isotherms, (equilibrium) phase transition conditions, limits of stability, and free energies for a number of different flexible adsorbent materials, distinguishable as different inputs into the models. While the models used in this work are relatively simple from a geometric perspective, they yield non-trivial adsorptive behavior, including adsorption-desorption hysteresis solely due to material flexibility and so-called “breathing” of the adsorbent. The observed effects can in turn be tied to the inherent properties of the bare adsorbent. Some of the effects are expected on physical grounds while others arise from a subtle balance of thermodynamic and mechanical driving forces. In addition, the computational strategy presented here can be easily applied to more complex models for flexible adsorbents.

  17. IEEE TRANSACTIONS ON IMAGE PROCESSING, VOL. 5, NO. 1, JANUARY 1996 155 histograms needed to arithmetic encode the quantizer indexes. Such

    E-Print Network [OSTI]

    Zeevi, Yehoshua Y. "Josh"

    .6 s. This does not include the time needed to fit GG models. The second pass that performs actualIEEE TRANSACTIONS ON IMAGE PROCESSING, VOL. 5, NO. 1, JANUARY 1996 155 histograms needed by arithmetic coding in our simulations. The possible advantage of an adaptive arithmetic code needs

  18. Quantifying the Impact of Immediate Reconstruction in Postmastectomy Radiation: A Large, Dose-Volume Histogram-Based Analysis

    SciTech Connect (OSTI)

    Ohri, Nisha [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States)] [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Cordeiro, Peter G. [Department of Plastic Surgery, Memorial Sloan-Kettering Cancer Center, New York, New York (United States)] [Department of Plastic Surgery, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Keam, Jennifer [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States)] [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Ballangrud, Ase [Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, New York (United States)] [Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Shi Weiji; Zhang Zhigang [Department of Biostatistics and Epidemiology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States)] [Department of Biostatistics and Epidemiology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Nerbun, Claire T.; Woch, Katherine M.; Stein, Nicholas F.; Zhou Ying [Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, New York (United States)] [Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); McCormick, Beryl; Powell, Simon N. [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States)] [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Ho, Alice Y., E-mail: HoA1234@mskcc.org [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States)

    2012-10-01T23:59:59.000Z

    Purpose: To assess the impact of immediate breast reconstruction on postmastectomy radiation (PMRT) using dose-volume histogram (DVH) data. Methods and Materials: Two hundred forty-seven women underwent PMRT at our center, 196 with implant reconstruction and 51 without reconstruction. Patients with reconstruction were treated with tangential photons, and patients without reconstruction were treated with en-face electron fields and customized bolus. Twenty percent of patients received internal mammary node (IMN) treatment. The DVH data were compared between groups. Ipsilateral lung parameters included V20 (% volume receiving 20 Gy), V40 (% volume receiving 40 Gy), mean dose, and maximum dose. Heart parameters included V25 (% volume receiving 25 Gy), mean dose, and maximum dose. IMN coverage was assessed when applicable. Chest wall coverage was assessed in patients with reconstruction. Propensity-matched analysis adjusted for potential confounders of laterality and IMN treatment. Results: Reconstruction was associated with lower lung V20, mean dose, and maximum dose compared with no reconstruction (all P<.0001). These associations persisted on propensity-matched analysis (all P<.0001). Heart doses were similar between groups (P=NS). Ninety percent of patients with reconstruction had excellent chest wall coverage (D95 >98%). IMN coverage was superior in patients with reconstruction (D95 >92.0 vs 75.7%, P<.001). IMN treatment significantly increased lung and heart parameters in patients with reconstruction (all P<.05) but minimally affected those without reconstruction (all P>.05). Among IMN-treated patients, only lower lung V20 in those without reconstruction persisted (P=.022), and mean and maximum heart doses were higher than in patients without reconstruction (P=.006, P=.015, respectively). Conclusions: Implant reconstruction does not compromise the technical quality of PMRT when the IMNs are untreated. Treatment technique, not reconstruction, is the primary determinant of target coverage and normal tissue doses.

  19. On Clustering Histograms with k-Means by Using Mixed -Divergences Entropy 16(6): 3273-3301 (2014). bibTEX:J2014-ClusteringMixedDivergence [1

    E-Print Network [OSTI]

    Nielsen, Frank

    2014-01-01T23:59:59.000Z

    On Clustering Histograms with k-Means by Using Mixed -Divergences Entropy 16(6): 3273-3301 (2014 -divergence is defined by S,(p : q) = D(p : q) + (1 - )D(q : p) = M,(q : p : q). We describe hard k-means type cou- pled k-means where each cluster has two dual centroids, and show how to extend the k-means

  20. Small Employer Quality Jobs 7-Year Cash Incentive (Oklahoma)

    Broader source: Energy.gov [DOE]

    This program provides incentive payments to a qualifying small employer (90 employees or less). The payments may reach as high as 5% of new taxable payroll and last for up to seven years. Annual...

  1. Microsoft Word - CFAC 7-Year PSA.doc

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    G. "FTE" shall mean full time annual equivalent employment (including part-time and partial year) for regular employees of CFAC at the CFAC Plant and contractor employees...

  2. Microsoft Word - CFAC 7-Year PSA.doc

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville PowerCherries 82981-1cnHighandSWPA / SPRA / USACE SWPAURTeC:8 3. MarchFigure 1CAMDCBFO Draft is

  3. Postnatal Testosterone and Autistic Traits in 4- to 7-Year-Old Children

    E-Print Network [OSTI]

    Saenz, Janet

    2014-10-30T23:59:59.000Z

    levels of empathy) has been linked to internalizing disorders during adolescence (Zahn-Waxler, Shirtcliff, & Marceau, 2008). Another 6 hypothesis to explain why disorders more commonly diagnosed in females (e.g., mood disorders, anxiety disorders...

  4. Boosting Monte Carlo Rendering by Ray Histogram Fusion MAURICIO DELBRACIO

    E-Print Network [OSTI]

    Kazhdan, Michael

    and Universidad de la Rep´ublica, Uruguay PABLO MUS ´E Universidad de la Rep´ublica, Uruguay ANTONI BUADES ENS), ENS-Cachan, France, mdelbra@fing.edu.uy; P. Mus´e, Universidad de la Rep´ublica, Montevideo, Uruguay

  5. Outrunning major weight gain: a prospective study of 8,340 consistent runners during 7 years of follow-up

    E-Print Network [OSTI]

    Williams, Paul T.

    2008-01-01T23:59:59.000Z

    groups (X-axis) and percentile of weight change (legend).trend going from the smallest to the highest percentile (percentile effect). Brackets designate ±SE.

  6. HISTOGRAM OF CONFIDENCES FOR PERSON DETECTION Lee Middleton, James R. Snowdon

    E-Print Network [OSTI]

    for this work. Typical industrial environments are harsh for image processing. They suffer from rapid lighting This paper focuses on the problem of person detection in harsh industrial environments. Different image work we adapt a previously trained classifier to improve its performance in the industrial environment

  7. Random Sets and Histograms Javier Nu~nez-Garcia and Olaf Wolkenhauer

    E-Print Network [OSTI]

    Rostock, Universität

    of a small sam- ple of data than a probability density function regardless of its asymptotic properties- ferent stochastic processes. Some people have already exploited the connection between proba- bility not differ much from that of a random variable. While random variables deal with stochastic point processes

  8. Image segmentation using local spectral histograms and linear regression Jiangye Yuan a,

    E-Print Network [OSTI]

    Wang, DeLiang "Leon"

    , Center for Cognitive Science, The Ohio State University, Columbus, OH 43210, United States a r t i c l e filterbanks to decompose an image into a set of sub-bands. Filtering methods have received experimental sup- ports on human texture perception and have shown impressive per- formance for texture segmentation

  9. A flat histogram method for inference with probabilistic and deterministic constraints

    E-Print Network [OSTI]

    Keinan, Alon

    probabilistic and deterministic dependencies are present at the same time is a challenging task with many real-world for an appropri- ate energy function, where the density of states is defined as a function that for each energy level E gives the number of configurations with that energy. We propose a novel Markov Chain Monte Carlo

  10. Face Detection Using Spectral Histograms and SVMs Christopher A. Waring and Xiuwen Liu

    E-Print Network [OSTI]

    Liu, Xiuwen

    . Accordingly, existing face detection approaches fall into one of four categories (see [32] for a recent survey): knowledge-based methods, template-based meth- ods, feature invariant methods, or appearance-based methods, non-face patterns will be included in the face class, resulting in false positives. Template

  11. Workload-Aware Histograms for Remote Applications Tanu Malik and Randal Burns

    E-Print Network [OSTI]

    Burns, Randal

    popular data structure is the I.-Y. Song, J. Eder, and T.M. Nguyen (Eds.): DaWaK 2008, LNCS 5182, pp. 402

  12. Statistics 36-315: Statistical Graphics and Visualization Lab 2: Histograms and Alternatives

    E-Print Network [OSTI]

    Fienberg, Stephen E.

    to My Documents: File -> Change dir... 5. Load the special functions for this lab by typing Windows -> Tile. Load the data 7. Read the csv file into an R data frame, by typing into the command the handout on the density.curve function, plot a density curve for x. You do not need to create a new window

  13. Correlated histogram representation of Monte Carlo derived medical accelerator photon-output phase space

    DOE Patents [OSTI]

    Schach Von Wittenau, Alexis E. (Livermore, CA)

    2003-01-01T23:59:59.000Z

    A method is provided to represent the calculated phase space of photons emanating from medical accelerators used in photon teletherapy. The method reproduces the energy distributions and trajectories of the photons originating in the bremsstrahlung target and of photons scattered by components within the accelerator head. The method reproduces the energy and directional information from sources up to several centimeters in radial extent, so it is expected to generalize well to accelerators made by different manufacturers. The method is computationally both fast and efficient overall sampling efficiency of 80% or higher for most field sizes. The computational cost is independent of the number of beams used in the treatment plan.

  14. Computing and Partitioning Cloud Feedbacks Using Cloud Property Histograms. Part I: Cloud Radiative Kernels

    E-Print Network [OSTI]

    Hartmann, Dennis

    radiative forcing. The global and annual mean model-simulated cloud feedback is dominated by contributions to a hypothetical cloudless but other- wise identical planet, the global and annual mean effect of clouds at the top is how cloud radiative effects will change as the planet warms because of long-lived greenhouse gases

  15. Comparison of Cloud Top Height and Optical Depth Histograms from ISCCP,

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville Power Administration would like submit the followingth Lomonosov1CompactComparison ofposter,MISR,

  16. This article appeared in a journal published by Elsevier. The attached copy is furnished to the author for internal non-commercial research

    E-Print Network [OSTI]

    stabilization mechanism and causes cells to tumble. Particle and continuum models are compared statistically to the development of the observed cell concentrations. & 2012 Elsevier Ltd. All rights reserved. 1. Introduction and Sherman, 1984; Klaassen and Peltier, 1985, 1991; Caulfield and Peltier, 1994, 2000; Smyth and Moum, 2001

  17. Gamma ray spectroscopy employing divalent europium-doped alkaline earth halides and digital readout for accurate histogramming

    DOE Patents [OSTI]

    Cherepy, Nerine Jane; Payne, Stephen Anthony; Drury, Owen B; Sturm, Benjamin W

    2014-11-11T23:59:59.000Z

    A scintillator radiation detector system according to one embodiment includes a scintillator; and a processing device for processing pulse traces corresponding to light pulses from the scintillator, wherein pulse digitization is used to improve energy resolution of the system. A scintillator radiation detector system according to another embodiment includes a processing device for fitting digitized scintillation waveforms to an algorithm based on identifying rise and decay times and performing a direct integration of fit parameters. A method according to yet another embodiment includes processing pulse traces corresponding to light pulses from a scintillator, wherein pulse digitization is used to improve energy resolution of the system. A method in a further embodiment includes fitting digitized scintillation waveforms to an algorithm based on identifying rise and decay times; and performing a direct integration of fit parameters. Additional systems and methods are also presented.

  18. Section Based Program Analysis to Reduce Overhead of Detecting Unsynchronized Thread Communication

    E-Print Network [OSTI]

    Das, Madan Mohan

    2015-01-01T23:59:59.000Z

    fft lu radix histogram kmeans matrix multiply pca reversefft lu radix histogram kmeans matrix multiply 1 pca reversePhoenix histogram (hi), kmeans (km), linear regression (lr),

  19. Proton radiotherapy for orbital rhabdomyosarcoma: Clinical outcome and a dosimetric comparison with photons

    SciTech Connect (OSTI)

    Yock, Torunn [Department of Radiation Oncology, Massachusetts General Hospital, Harvard Medical School, Boston, MA (United States)]. E-mail: tyock@partners.org; Schneider, Robert C. [Department of Radiation Oncology, Massachusetts General Hospital, Harvard Medical School, Boston, MA (United States); Friedmann, Alison [Department of Radiation Oncology, Massachusetts General Hospital, Harvard Medical School, Boston, MA (United States); Adams, Judith C. [Department of Radiation Oncology, Massachusetts General Hospital, Harvard Medical School, Boston, MA (United States); Fullerton, Barbara [Department of Radiation Oncology, Massachusetts General Hospital, Harvard Medical School, Boston, MA (United States); Tarbell, Nancy [Department of Radiation Oncology, Massachusetts General Hospital, Harvard Medical School, Boston, MA (United States)

    2005-11-15T23:59:59.000Z

    Background: Over 85% of pediatric orbital rhabdomyosarcoma (RMS) are cured with combined chemotherapy and radiation. However, the late effects of photon radiation compromise function and cosmetic outcome. Proton radiation can provide excellent tumor dose distributions while sparing normal tissues better than photon irradiation. Methods and Materials: Conformal 3D photon and proton radiotherapy plans were generated for children treated with proton irradiation for orbital RMS at Massachusetts General Hospital. Dose-volume histograms (90%, 50%, 10%) were generated and compared for important orbital and central nervous system structures. Average percentages of total dose prescribed were calculated based on the 3 dose-volume histogram levels for normal orbital structures for both the proton and photon plans. The percent of normal tissue spared by using protons was calculated. Results: Seven children were treated for orbital rhabdomyosarcoma with proton irradiation and standard chemotherapy. The median follow-up is 6.3 years (range, 3.5-9.7 years). Local and distant controls compare favorably to those in other published accounts. There was an advantage in limiting the dose to the brain, pituitary, hypothalamus, temporal lobes, and ipsilateral and contralateral orbital structures. Tumor size and location affect the degree of sparing of normal structures. Conclusions: Fractionated proton radiotherapy is superior to 3D conformal photon radiation in the treatment of orbital RMS. Proton therapy maintains excellent tumor coverage while reducing the radiation dose to adjacent normal structures. Proton radiation therapy minimizes long-term side effects.

  20. Validation of computational approaches for studying disordered and unfolded protein dynamics using polymer models

    E-Print Network [OSTI]

    Phillips, Joshua Lee

    2012-01-01T23:59:59.000Z

    Direct Application of K-means Clustering . . . . . . .Nups . . . . . . . . . . . . . . 3.3.2. K-means ClusteringHistograms, 3ns . . K-means Clustering Histograms, 3ns .

  1. Explaining the Price of Voluntary Carbon Offsets

    E-Print Network [OSTI]

    Conte, Marc N.; Kotchen, Matthew

    2009-01-01T23:59:59.000Z

    Energy and Sustainable Development, Stanford Univer- sity. Figure 1: Histogram of carbon offset prices (

  2. Human Detection and Character Recognition in TV-Style Alexander Klaser

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    with k-means. A non-linear multi-class Support Vector Machine (SVM) is learned on occurrence histograms into shots. The shot detection is based on the comparison of color histograms of successive frames. Human

  3. Nonparametric function estimation with infinite-order kernels and applications

    E-Print Network [OSTI]

    Berg, Arthur Steven

    2007-01-01T23:59:59.000Z

    2.5.3 GARCH Model . . . . . . . . . . . . . . . . . 2.5.4N = 2000. . . estimates on garch data for N = 200 and N =data. . Histograms based on garch data. . Histograms based

  4. Inferior-Colliculus Responses to Amplitude-Modulated and Unmodulated Acoustic Tones and Cochlear-Implant Pulse Trains

    E-Print Network [OSTI]

    Schoenecker, Matthew Charles

    2010-01-01T23:59:59.000Z

    histogram images show that the responses to the acoustic SAMhistogram images. A. One period (50-Hz SAM) or two periods (

  5. Proceedings of the 1998 IEEE International Conference on Robotics and Automation. Leuven, Belgium, May 1621, 1998, pp. 1572 -1577 VFH+: Reliable Obstacle Avoidance for Fast Mobile Robots

    E-Print Network [OSTI]

    Borenstein, Johann

    to this algorithm is a map grid of the local environment, called histogram grid [Borenstein and Koren, 1991], which. In the first three stages, the two-dimensional map grid is reduced to one-dimensional polar histograms the active region Ca of the map grid C onto the primary polar histogram Hp . The active region Ca

  6. LIFE Economics and Delivery Pathway Presentation to

    E-Print Network [OSTI]

    utilities Install Process Equipment infrastructure Install & commission LRUs Inert / low yield commissioning design 7 years build 7 years qualification Anklam--NAS/NA

  7. The Electric Sense of the Thornback Ray, Platyrhinoidis triseriata : Linear Dynamic Range in Single-Unit Electrophysiological Recordings in vivo from the Afferent Nerve Fibers of the Ampullae of Lorenzini

    E-Print Network [OSTI]

    Gonzalez, Ivan F

    2008-01-01T23:59:59.000Z

    Non-linear regression . . . . . . . . . . . . . . . . . . . . . . . . . . . . .the system. We use non-linear regression to ?t a sinusoidalthe histogram using non-linear regression, we use analysis

  8. The electric sense of the Thornback Ray, Platyrhinoidis triseriata : linear dynamic range in single-unit electrophysiological recordings in vivo from the afferent nerve fibers of the Ampullae of Lorenzini

    E-Print Network [OSTI]

    Gonzalez, Ivan F.

    2008-01-01T23:59:59.000Z

    Non-linear regression . . . . . . . . . . . . . . . . . . . . . . . . . . . . .the system. We use non-linear regression to ?t a sinusoidalthe histogram using non-linear regression, we use analysis

  9. adaptive bin framework: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Lin, Lin; Ying, Lexing; E, Weinan 2011-01-01 163 Multifractal Diffusion Entropy Analysis: Optimal Bin Width of Probability Histograms CERN Preprints Summary: In the framework...

  10. activates leucine aminopeptidase: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    chi values surrounding the common rotameric states of leucine and valine. Relative free enegy slices were calculated from the biased trajectories using the weighted histogram...

  11. acid biosynthesis leucine: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    chi values surrounding the common rotameric states of leucine and valine. Relative free enegy slices were calculated from the biased trajectories using the weighted histogram...

  12. assessment calculations related: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    chi values surrounding the common rotameric states of leucine and valine. Relative free enegy slices were calculated from the biased trajectories using the weighted histogram...

  13. Cape Canaveral Air Force Station integrated resource assessment. Volume 2, Baseline detail

    SciTech Connect (OSTI)

    Wahlstrom, R.R.; McMordie, K.L.; Parker, S.A.; King, D.A.; Sandusky, W.F.

    1993-12-01T23:59:59.000Z

    The US Air Force (USAF) has tasked the Pacific Northwest Laboratory (PNL), in support of the US Department of Energy (DOE) Federal Energy Management Program (FEMP), to assess energy use at Cape Canaveral Air Force Station (AFS). The information obtained from this assessment will be used in identifying energy resource opportunities to reduce overall energy consumption by the station. The primary focus of this report is to assess the current baseline energy consumption at Cape Canaveral AFS. It is A companion report to Volume 1, the Executive Summary, and Volume 3, the Resource Assessment. This assessment requires that information be obtained and characterized for buildings, utilities, energy sources, energy uses, and load profiles to be used to improve the current energy system on the station. The characteristics of electricity, diesel fuel, No. 2 fuel oil, and motor vehicle gasoline (MOGAS) are analyzed for on-base facilities. The assessment examines basic regional information used to determine energy-use intensity (EUI) values for Cape Canaveral AFS facilities by building, fuel type, and energy end use. It also provides a summary of electricity consumption from Florida Power and Light Company (FPL) metered data for 1985--1991. Load profile information obtained from FPL data is presented for the North, South, and Titan Substations for the four seasons of the year, including weekdays and weekends.

  14. Estimating HAPs and radionuclide emissions from a laboratory complex at a nuclear processing site

    SciTech Connect (OSTI)

    Paul, R.A. [IT Corp., Durham, NC (United States); Faugl, T. [Westinghouse Savannah River Co., Aiken, SC (United States)

    1993-10-01T23:59:59.000Z

    A unique methodology was developed for conducting an air emission inventory (AEI) at a DOE nuclear processing facility. This methodology involved the use of computer-assisted design (CAD) drawings to document emission points, computerized process drawings to document industrial processes leading to emissions, and a computerized data base of AEI forms to document emission estimates and related process data. A detailed air emissions inventory for operating years 1985--1991 was recently implemented for the entire site using this methodology. One industrial area at the DOE Site is comprised of laboratory facilities that provide direct support to the nuclear reactor and recovery operations, developmental studies to support reactor and separation operations, and developmental studies to support waste handling and storage. The majority of the functions are conducted in a single large building complex wherein bench scale and pilot scale experiments are carried out involving radionuclides, hazardous air pollutants (HAP), and other chemicals reportable under the Clean Air Act Amendments (CAAA) and Superfund Amendments and Re-authorization Act (SARA) Title 111. The results of the inventory showed that HAP and radionuclide emissions from the laboratory complex were relatively minor.

  15. Fractal laser glints from the ocean surface Joseph A. Shaw and James H. Churnside

    E-Print Network [OSTI]

    Shaw, Joseph A.

    Fractal laser glints from the ocean surface Joseph A. Shaw and James H. Churnside National Oceanic of laser glint counts from the ocean surface exhibit fractal behavior. Glint-count histogram widths do not follow Gaussian statistics, and histogram shapes are approximately log normal. Fractal dimen- sions

  16. Life-History Traits Of Chrysomya rufifacies (Macquart) (Diptera: Calliphoridae) And Its Associated Non-Consumptive Effects On Cochliomyia macellaria (Fabricius) (Diptera: Calliphoridae) Behavior And Development

    E-Print Network [OSTI]

    Flores, Micah

    2013-07-24T23:59:59.000Z

    .................................................... 1 Factors Affecting Development ..................................................... 2 Biology of the Secondary Screwworm ........................................... 7 Biology of the Hairy Maggot Blow Fly...) ...................................................... 30 7 Histogram of predicted proportion of development minus true proportion of development to determine how close model 14 predictions are to true age of unknown age larvae (predicted-true=0) ...... 58 8 Histogram of predicted...

  17. Hindawi International Journal of Vehicular Technology, Vol. x, No. x, xxxx 1 Driving Posture Recognition by Joint

    E-Print Network [OSTI]

    Coenen, Frans

    Recognition by Joint Application of Motion History Image and Pyramid Histogram of Oriented Gradients Chao Yan history image, followed by application of the Pyramid Histogram of Oriented Gradients (PHOG) for more of personal-use automobiles has continued to grow at a rapid rate, reaching the number 120,890,000 in 2012

  18. Application of High-performance Visual Analysis Methods to Laser Wakefield Particle Acceleration Data

    E-Print Network [OSTI]

    Application of High-performance Visual Analysis Methods to Laser Wakefield Particle Acceleration, time- varying laser wakefield particle accelerator simulation data. We ex- tend histogramBit, a state-of-the-art index/query technology, to acceler- ate data mining and multi-dimensional histogram

  19. Edge detectors find differences in overall intensity.

    E-Print Network [OSTI]

    Jacobs, David

    , compute Gabor Jet at each pixel. · Cluster all pixels (using k-means) to get ~100 clusters. · For each/why to compare · Simplest comparison is SSD, many others. · Can view probabilistically. ­ Histogram is a set come from same distribution? #12;More Complex Discrimination · Histogram comparison is very limiting

  20. This work was sponsored by the Department of Energy Grant DE-FG02-86NE379691 Reprint of Proceedings of the 1990 IEEE International Conference on Robotics and Automation,

    E-Print Network [OSTI]

    Borenstein, Johann

    This work was sponsored by the Department of Energy Grant DE-FG02-86NE379691 Page 572 Reprint uses a two-dimensional Cartesian Histogram Grid as a world model. This world model is updated that is constructed around the robot's momentary location. Each sector in the Polar Histogram holds the polar obstacle

  1. An analysis of winter precipitation in the northeast and a winter weather precipitation type forecasting tool for New York City 

    E-Print Network [OSTI]

    Gordon, Christopher James

    1999-01-01T23:59:59.000Z

    1's accuracy in forecasting frozen precipitation. . . . 60 23 25 Same as FIG. 22 except for model 2 . . . . Same as FIG. 22 except for model 3 . . . . Same as FIG. 22 except for model 4 . . . . 61 62 26 Histogram of responses for snow cases... to the logistic regression analysis of snow cases versus rain cases for model 1. 64 FIGURE Page 27 Histogram of responses for rain cases to the logistic regression analysis of snow cases versus rain cases for model 1 28 Histogram of responses for snow cases...

  2. Improving the Yeast Three-Hybrid System for High-Throughput Target Discovery

    E-Print Network [OSTI]

    Bailey, Kyle

    2011-05-27T23:59:59.000Z

    fluorescence produced with only the yEGFP reporter (light gray) and maximal fluorescence with reporter activated by a LexA-B42 fusion (dark gray). Taken with permission from (Clark, D. D.; Peterson, B. R. Chembiochem 2005, 6, 1442). ............ 28 Figure 2... of induced yeast lacking LexA-B42 (red histogram). C) Table of relevant statistics taken from histograms. The median signal and coefficient of variation (CV) is taken from the gated population of induced cells bearing the complete system (black histogram...

  3. Charge fluctuations in nano-scale capacitors David T. Limmer1

    E-Print Network [OSTI]

    Boyer, Edmond

    these fluctuations using molecular dynamics simulations in a constant-potential ensemble with histogram reweighting of electric current fluctuations [14, 15], ignore the fluctuations we consider. During the past decade

  4. ISpace: Interactive Volume Data Classification Techniques Using Independent Component Analysis

    E-Print Network [OSTI]

    Ma, Kwan-Liu

    , multivariate data analysis, multimodality data, scientific visualization, seg- mentation, volume rendering 1ISpace: Interactive Volume Data Classification Techniques Using Independent Component Analysis, which uses Independent Component Analysis (ICA) and a multi- dimensional histogram of the volume data

  5. Viewpoint-Invariant Learning and Detection of Human Heads M. Weber W. Einhauser

    E-Print Network [OSTI]

    Perona, Pietro

    Viewpoint-Invariant Learning and Detection of Human Heads M. Weber W. Einh¨auser California on histograms of feature detectors to address the same prob- lem. Burl, Leung, Weber and Perona [1] additionally

  6. A Measurement of the Cosmic Background Radiation Temperature at 3.0 cm

    E-Print Network [OSTI]

    Friedman, S.D.; Smoot, G.F.; De Amici, G.; Witebsky, C.

    1983-01-01T23:59:59.000Z

    1. Figure 2. Schematic of the 3.0 cm radiometer. HistogramRADIATION TEMPERATURE AT 3.0 cm S.D. Friedman, G.F. Smoot,Radiation Temperature at 3.0 cm Scott D . Friedman, George

  7. ANL/APS/TB-54, Dose Calculations using MARS for Bremsstrahlung...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    of dose histogram definitions. Also, a case was run without shielding to examine build-up factor. The simulation geometry for the case of a 20-cm-thick Pb beam stop is...

  8. Operational profiling and statistical analysis of Arleigh Burke-class destroyers

    E-Print Network [OSTI]

    Anderson, Travis J. (Travis John)

    2013-01-01T23:59:59.000Z

    Ship operational profiles are a valuable tool for ship designers and engineers when analyzing potential designs and ship system selections. The most common is the speed-time profile, normally depicted as a histogram showing ...

  9. Version of 1st May 1999 Analysis of

    E-Print Network [OSTI]

    DIS suppressed by t 0 cut, remaining contribution removed with PEPSI Monte Carlo Points: data; Histogram: PEPSI Normalised at #1;E > 3; Shaded area: signal region j#1;Ej

  10. Stat 328 1st Week Outline 1 Introduction

    E-Print Network [OSTI]

    Vardeman, Stephen B.

    .e. must not be changing in a completely unpredictable fashion over time. (SPC methods are aimed and leaf diagrams -histograms (bar charts) ·numerical summaries -sample minimum and sample maximum

  11. asfyksi prognose ud fra: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    The MLT allows UDs with very low contrast to be reliably identified. Inside the umbra we determine a UD filling factor of 11%. The histogram of UD lifetimes is monotonic,...

  12. adherence distribution evolution: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    The MLT allows UDs with very low contrast to be reliably identified. Inside the umbra we determine a UD filling factor of 11%. The histogram of UD lifetimes is monotonic,...

  13. Mentors' perceptions of the effectiveness of the components and technological venues implemented in online teacher induction programs for novice teachers

    E-Print Network [OSTI]

    Livengood, Kimberly K.

    2007-04-25T23:59:59.000Z

    ????????????????????????????..? 278 xi LIST OF FIGURES FIGURE Page 3.1 Conceptual Framework of Online Teacher Induction Programs?. 64 4.1 Histogram of Perceived Effectiveness of the Professional Development Component??????..?????????? 83 4.2 Normal Q-Q... Plot of Perceived Effectiveness of the Professional Development Component ????????.?? 84 4.3 Histogram of the Perceived Effectiveness of the Emotional Support Component ????????????????..? 86 4.4 Normal Q-Q Plot of the Perceived...

  14. The relationship between grain yield and waxy endosperm in Sorghum bicolor (Linn.) Moench

    E-Print Network [OSTI]

    Aydin, Selahattin

    2005-08-29T23:59:59.000Z

    OF FIGURES FIGURE 1 Histogram of B-line genotypes classed by mean grain yield (kg/ha-1). Entries are color-coded based on endosperm type. A. College Station, 1998. B. College Station, 1999. C. College Station, 2000. D. Lubbock, 1998. E.... Lubbock, 1999.??????????....??..???????..42 2 Histogram of B-line genotypes classed by genotype mean plant height (cm). Entries are color-coded based on endosperm type. A. College Station, 1998. B. College Station, 1999. C. College Station, 2000...

  15. Exploration of Ion-Exchanged Glass for Seals Applications

    E-Print Network [OSTI]

    Ghanbari, Roushan

    2012-10-19T23:59:59.000Z

    ........................................................................................................ 34 Figure 15. Semitransparent overlay of two images created using the MATLAB ........... 35 Figure 16. Binary, composite image of samples 5 and 7 ............................................... 37 Figure 17. Histogram of „3 leaf? composite images... with normal fit overlay .................. 41 Figure 18. Probability plot of „3 leaf? composite images with normal fit ...................... 42 Figure 19. Histogram of „4 leaf? composite images with normal fit overlay .................. 43 x Page Figure...

  16. Streamline Assisted Ensemble Kalman Filter - Formulation and Field Application

    E-Print Network [OSTI]

    Devegowda, Deepak

    2010-10-12T23:59:59.000Z

    . .............................................................................................................10 Figure 1.3 Comparison of the updated permeability fields on the right with the initial fields on the left for four realizations of the ensemble of 25 members.... ....................................................................................................13 Figure 1.4 (a) is the initial permeability histogram on the left with the updated histogram on the right in (b) for an ensemble size of 25. ..........................14 Figure 1.5 Comparison of the updated permeability fields on the right...

  17. Response of breeding seaside sparrows to fire on the upper Texas Coast

    E-Print Network [OSTI]

    Whitbeck, Matthew W

    2002-01-01T23:59:59.000Z

    ), Error bars represent standard deviations. Histogram represents precipitation recorded in 2000 and 2001 on Anahuac National Wildlife Refuge, Chambers County, Texas (USFWS, unpubl. data) 23 Mean number of Seaside Sparrows/survey for four years post..., Chambers County, Texas 1986 - 2001 (J. Neaville, unpubl. data). Error bars represent standard deviations. Histogram represents precipitation recorded in 2000 and 2001 on Anahuac National Wildlife Refuge, Chambers County, Texas (USFWS, unpubh data). 24...

  18. Identification of the impacts of maintenance and testing upon the safety of LWR power plants. Part II. Final report

    SciTech Connect (OSTI)

    Husseiny, A. A.; Sabri, Z. A.; Turnage, J. J.

    1980-04-01T23:59:59.000Z

    Information is presented concerning overview of literature relating to radiation exposure and operating experience; details of LWR-MTC3 classification system; histograms for individual BWR facilities depicting frequency of M and T mode and frequency of systems and components involved with M and T problems; histograms for individual PWR facilities depicting frequency of M and T mode and frequency of systems and components involved with M and T problems; and Fortran program for M and T data clustering.

  19. Atmosphere to Electrons Initiative Takes Shape | Department of...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    (industry, national laboratories, international experts, and universities) over the next 5- to 7 years. In February, they held an external merit review committee made up of...

  20. arabidopsis reduces drought: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    fire occurrence compared to the averages of previous 7 years. Atmospheric data analysis and modeling results suggest that the 2005 drought was caused largely by a warm...

  1. Wader Ringing in South Africa

    E-Print Network [OSTI]

    Journal:  Wader Study Group Bulletin Attachment Size p00018-p00018.pdf 81.52 KB Issue:  7 Year:  1972 Pages:  18

  2. Microsoft Word - Summary of BPA's Use of the Regional Economic...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Draft Contract This document summarizes BPA's use of the 2006 Regional Employment and Economic Study to contemplate the 7-year draft power sale contract that proposes to make...

  3. THE CITY UNIVERSITY OF NEW YORK Classified Civil Service Position Description

    E-Print Network [OSTI]

    Rosen, Jay

    and equipment. - Supervises, directs and is responsible for the proper operation of the departmental carpentry, promenades, etc. - Keeps records and prepares reports. Qualification Requirements 1. Seven (7) years

  4. Interface Tensions and Perfect Wetting in the Two-Dimensional Seven-State Potts Model

    E-Print Network [OSTI]

    B. Grossmann; Sourendu Gupta

    1993-10-25T23:59:59.000Z

    We present a numerical determination of the order-disorder interface tension, \\sod, for the two-dimensional seven-state Potts model. We find $\\sod=0.0114\\pm0.0012$, in good agreement with expectations based on the conjecture of perfect wetting. We take into account systematic effects on the technique of our choice: the histogram method. Our measurements are performed on rectangular lattices, so that the histograms contain identifiable plateaus. The lattice sizes are chosen to be large compared to the physical correlation length. Capillary wave corrections are applied to our measurements on finite systems.

  5. This file is a draft version It may be different from the published version Vol. 1, No. 1, pp. 64-72, 2008.06

    E-Print Network [OSTI]

    Tokyo, University of

    > in 2.4 3CCD 3CCD 1 Table 1 Comparison between reflection separation methods. We categorized polarizer Line fitting No Lin16) R-0º, G-60º, B-120º Histogram comparison Difficult*1 U 37) Li l i ICA Diffi lt*2 *1 *2 Umeyama37) Linear polarizer ICA Difficult*2 Correct 1 Table 1 Comparison

  6. FRACTAL ANALYSIS TOOLS FOR CHARACTERIZING THE COLORIMETRIC ORGANIZATION OF DIGITAL IMAGES

    E-Print Network [OSTI]

    Chapeau-Blondeau, François

    FRACTAL ANALYSIS TOOLS FOR CHARACTERIZING THE COLORIMETRIC ORGANIZATION OF DIGITAL IMAGES Case.chapeau-blondeau}@univ-angers.fr Keywords: Color image, Color histogram, Fractal, Self-similarity, Capacity dimension, Correlation dimension of algorithms which can characterize fractal organizations in the support and population of their three

  7. Experimental Study of Free Stream Turbulence Effects on Dynamic Stall of Pitching Airfoil by using Particle Image Velocimetry

    E-Print Network [OSTI]

    Leu, Tzong-Shyng "Jeremy"

    of attack histogram of a vertical axis wind turbine (VAWT). By using PIV, the instantaneous vortex, a great deal of attention has been paid to investigate the aerodynamic performance of vertical-axis wind turbines (VAWT) [4-6]. VAWT often operates inside an atmospheric turbulent boundary layer. The purpose

  8. Conf. on Polar Meteorology and Oceanography, 9-13 Jan 2005, San Diego, CA 7.1 DETERMINING WINTERTIME HETEROGENEOUS PACK ICE CHARACTERISTICS AND

    E-Print Network [OSTI]

    Persson, Ola

    WINTERTIME HETEROGENEOUS PACK ICE CHARACTERISTICS AND THEIR IMPACT ON THE AGGREGATE ATMOSPHERIC SURFACE) over the Arctic pack ice during clear-sky wintertime conditions. These histograms were remarkable) data and a simple one- dimensional snow and ice model. The SAR data show the time of the formation

  9. VOLUME 77, NUMBER 16 P H Y S I C A L R E V I E W L E T T E R S 14 OCTOBER 1996 Thermal Activation above a Dissipation Barrier: Switching of a Small Josephson Junction

    E-Print Network [OSTI]

    Devoret, Michel H.

    connected to a RC impedance providing large damping. The diffusion branch and the switching histograms in the neighborhood of a metastable attractor A0 (see Fig. 1), such systems follow, at finite temperature T, dif of a lower energy at- tractor A1. In the usual case of the escape from a po- tential well [shown in Fig. 1(a

  10. AIAA980057 RELATING TURBULENCE TO WIND TURBINE BLADE LOADS

    E-Print Network [OSTI]

    Sweetman, Bert

    AIAA­98­0057 RELATING TURBULENCE TO WIND TURBINE BLADE LOADS: PARAMETRIC STUDY WITH MULTIPLE that is most useful in estimating fatigue loads on wind turbine blades. The histograms of rainflow counted turbulence measures---can be used to estimate fatigue loads on wind turbine blades. We first de­ scribe

  11. AIAA-98-0057 RELATING TURBULENCE TO WIND TURBINE BLADE LOADS

    E-Print Network [OSTI]

    Sweetman, Bert

    AIAA-98-0057 RELATING TURBULENCE TO WIND TURBINE BLADE LOADS: PARAMETRIC STUDY WITH MULTIPLE that is most useful in estimating fatigue loads on wind turbine blades. The histograms of rain ow counted measures|can be used to estimate fatigue loads on wind turbine blades. We rst de- scribe a general approach

  12. Lifetime of high-k gate dielectrics and analogy with strength of quasibrittle Jia-Liang Le,1

    E-Print Network [OSTI]

    Bazant, Martin Z.

    , Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, USA 2 Department of Materials Science to breakdown i.e., the integral of the tunneling current over the lifetime .2,4 Re- cently, histogram testingLifetime of high-k gate dielectrics and analogy with strength of quasibrittle structures Jia

  13. ARF @ MediaEval 2012: Multimodal Video Classification Bogdan Ionescu1,5

    E-Print Network [OSTI]

    (LPCs), Line Spectral Pairs (LSPs), MFCCs, Zero-Crossing Rate (ZCR), and spectral centroid, flux, kurtosis, median and root mean square statistics over all frames. · feature detectors - from this category, we compute aver- age Histogram of oriented Gradients (HoG) over all frames, Speeded Up Robust Feature

  14. Reduction of Metal Artifacts in Computed Tomographies for the Planning and Simulation of Radiation Therapy

    E-Print Network [OSTI]

    Zerfowski, Detlef

    data histogram. Compared with continuous integral transform methods, iterative discrete reconstruction covering 180 . Acquisition of real patient data was performed using a Siemens Somatom Plus S CT scanner (Siemens Medical Engineering, Forchheim, Germany). For each slice, 1242 views covered a full rotation

  15. JOURNAL OF CHEMOMETRICS J. Chemometrics 2003; 17: 400412

    E-Print Network [OSTI]

    Ferreira, Márcia M. C.

    . Multivariate modeling of image data can help to provide insight into the important chemical factors present. However, many issues of how best to apply these models remain unclear, especially when the data arrays transformation techniques, such as chemical mapping and histograms, are found to be useful both for pretreatment

  16. Using Super-Vector Coding for Image Classification and Retrieval

    E-Print Network [OSTI]

    Tian, Qi

    .g. SIFT X1 X2 XN 128 N SIFTs ­ Bag-of-Word K-Means clusteringK dim Histogram K × N dim #12;Motivation derivative smooth K-Means (1) (2) #12;Descriptor Coding · Super-Vector (SV) coding #12;Descriptor Coding (2 #12;Experiments - Comparison of nonlinear coding methods |C| = 512 #12;Experiments - Comparison

  17. Semantic Image Segmentation Web-Supervised Visual Learning

    E-Print Network [OSTI]

    Kim, Tae-Kyun

    repr. 1 pixel L a b Lab colour- space L a b #12;Background: Texton Vocabulary K-Means 75 dim. feature centres) V = K in K-means ... #12;Map Features to Textons Training Images Feature Vectors per pixel Map Introduction to textons and single-class histogram models (SCHM) Comparison of nearest neighbour (NN

  18. PLOT2K: a graphics interface to System 2000

    SciTech Connect (OSTI)

    Creel, L.

    1981-01-01T23:59:59.000Z

    PLOT2K is an interactive graphics interface to the System 2000 data base management system. It runs on a CDC 6600 computer with an NOS or NOS/BE operating system. The graphics package used is DISSPLA. PLOT2K will generate bar chart histograms, pie charts, or x-y point plots and will access any System 2000 data base.

  19. The frequency of tropical precipitating clouds as observed by the TRMM PR and ICESat/GLAS

    E-Print Network [OSTI]

    Casey, Sean Patrick

    2009-06-02T23:59:59.000Z

    METHODOLOGY??????????????????? 11 A. Data??????????????????? 11 B. Analysis Method?????????????? 12 III COINCIDENT SCAN ANALYSIS????????????... 18 IV TROPICAL PRECIPITATING CLOUD FRACTION????? 23 V CONCLUSION????????????????????.. 31..., with land-ocean separation included.??????????????. 15 4 a) Horizontal scan and b) cross-section of a sample coincident case from 20 October 2003 over the eastern Democratic Republic of the Congo?????????????????????............. 19 5 Histograms...

  20. A Maximum Likelihood Investigation Into Color Indexing Nicu Sebe Michael S. Lew

    E-Print Network [OSTI]

    Sebe, Nicu

    the color components from the luminance compo- nent. The hue and saturation of a color are represented by H and S, and the luminance is represented by V. When we create a color histogram, we must quantize each is based on the observation that often color is used to encode functionality: grass is green, sky is blue

  1. Data Mining Middleware for Wide Area High Performance Networks

    E-Print Network [OSTI]

    Grossman, Robert

    1 Data Mining Middleware for Wide Area High Performance Networks Robert L. Grossman*, Yunhong Gu, David Hanley, and Michal Sabala National Center for Data Mining, University of Illinois at Chicago, USA astronomical data from the Sloan Digital Sky Survey (SDSS) and the other involves computing histograms from

  2. Clustering Moving Objects for Spatiotemporal Selectivity Estimation Qing Zhang Xuemin Lin

    E-Print Network [OSTI]

    Lin, Xuemin

    . To avoid expensive computation costs, we developed linear time heuristics to construct such a histogram of Computer Science and Engineering, University of New South Wales, Sydney, Australia 2052, Email: {qzhang, there are two kinds of queries based on different temporal natures. One is to query historical be­ havior

  3. Quantifying nonstationary radioactivity concentration fluctuations near Chernobyl: A complete statistical description

    E-Print Network [OSTI]

    Stanley, H. Eugene

    Quantifying nonstationary radioactivity concentration fluctuations near Chernobyl: A complete Chernobyl after the 1986 disaster and find three new results: i the histogram of fluctuations is well.60. x, 02.50.Fz, 05.45.Tp, 87.66.Na I. INTRODUCTION Chernobyl's No. 4 reactor was completely destroyed

  4. Quantifying nonstationary radioactivity concentration fluctuations near Chernobyl: A complete statistical description

    E-Print Network [OSTI]

    Shlyakhter, Ilya

    Quantifying nonstationary radioactivity concentration fluctuations near Chernobyl: A complete fluctuations measured near Chernobyl after the 1986 disaster and find three new results: #i# the histogram patterns. PACS number#s#: 89.60.#x, 02.50.Fz, 05.45.Tp, 87.66.Na I. INTRODUCTION Chernobyl's No. 4 reactor

  5. Machine Vision and Applications manuscript No. (will be inserted by the editor)

    E-Print Network [OSTI]

    Mihaylova, Lyudmila

    in videos produced by in- frared sensors (due to varying thermal conditions) and vis- ible sensors (e instead of the conventional Bhattacharyya histogram- based distance. Extensive evaluation of the proposed-world surveillance video sequences from multimodal (infrared and visible) ca- meras. Keywords structural similarity

  6. Supplementary Information ISI Data Collection Appendix

    E-Print Network [OSTI]

    Igic, Boris

    Supplementary Information ISI Data Collection Appendix We collected reports from which relative a measure along with transparent calculation procedures. We searched the online databases ISI Web explicitly. Negative ISI values were set to zero in the main text analyses. A histogram of unmodified ISI

  7. E791 DATA ACQUISITION SYSTEM Error reports received ; no new errors reported

    E-Print Network [OSTI]

    Fermi National Accelerator Laboratory

    of events written to tape. 18 #12; Error and Status Displays Mailbox For Histogram Requests Vax­online Event Display VAX 11 / 780 Event Reconstruction Event Display Detector Monitoring 3 VAX Workstations 42 EXABYTE of the entire E791 DA system. The VAX 11/780 was the user interface to the VME part of the system, via the DA

  8. Haar LBP Gabor Jet boosting Gabor Jet

    E-Print Network [OSTI]

    Ai, Haizhou

    Boosting 1 boosting Haar LBP Gabor Jet boosting LBP Haar Gabor Jet boosting TP391. Further more, three kinds of local feature, Haar like feature, LBP histogram and Gabor jet are extracted, Haar like feature is more efficient for discriminating young and middle aged people, and Gabor Jet fits

  9. IE 361 Class Outline, Fall 2004 Introduction/Chapter 1 (&Chapter 9)

    E-Print Network [OSTI]

    Vardeman, Stephen B.

    calculations SPC and engineering feedback control PID control algorithms "Advanced" Control Charts/Chapter 4 limits to get confidence limits for B8" elementary data collection principles histograms Pareto charts run charts Statistical Process Monitoring/Chapter 3 Process Measurement System Shewhart's grand

  10. STATISTICAL COMPUTING AND GRAPHICS

    E-Print Network [OSTI]

    Masci, Frank

    Marron for a helpful comment. @ 1997 American Statistical Association bin width should be chosen soSTATISTICAL COMPUTING AND GRAPHICS Data-Based Choice of Histogram Bin Width The most important of the "optimal" bin width. Default bin widths in most common statistical packages are, at least for large samples

  11. JOURNAL DE PHYSIQUE Colloque C6, suppl6ment au nO1l, Tome 49, novembre 1988

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    process. The first experiment concerns the decomposition of the ferrite in a duplex stainless steel tool then, is used for the interpretation of concentration profiles in a decomposed duplex stainless steel. The attraction of concentration histograms is also discussed in the case of the precipitation

  12. Relationship between classifier performance and distributional complexity for small samples

    E-Print Network [OSTI]

    Attoor, Sanju Nair

    2004-11-15T23:59:59.000Z

    units Fig. 11. Error estimate vs complexity N=60, sigma=1/10 29 0 5 10 15 20 25 300.05 0. 0.15 0. 0.25 0. 0.35 0. 0.45 0. Distributional Complexity Error Estimated Bayes Gaussian Kernel 3nn linear SVM Regular Histogram Neural Network with 2 hidden units...

  13. Analysis of a small sample geometry for concurrent identification and quantification of mixed-nuclide samples

    E-Print Network [OSTI]

    Krieger, Kenneth Vincent

    1999-01-01T23:59:59.000Z

    to each channel of the MCA is used to display a histogram, or spectrum, which is representative of the photon energy deposited in the crystal. * Aptec Instruments Inc. , 908 Niagara Falls Blvd, Ste 524, N. Tonawanda, NY. 14120. HPGe Detector Pre...

  14. BTRY 4830/6830: Quantitative Genomics and Genetics

    E-Print Network [OSTI]

    Keinan, Alon

    ;Review: topics covered · Working directory · R command line and GUI · input / output · R data structures happened?) · Now type the following on the command line (and re-try the same command, did it work a histogram · You can do this in one line of R code (!!) or in more lines, e.g. with a "for" loop · If you

  15. List mode multichannel analyzer

    DOE Patents [OSTI]

    Archer, Daniel E. (Livermore, CA); Luke, S. John (Pleasanton, CA); Mauger, G. Joseph (Livermore, CA); Riot, Vincent J. (Berkeley, CA); Knapp, David A. (Livermore, CA)

    2007-08-07T23:59:59.000Z

    A digital list mode multichannel analyzer (MCA) built around a programmable FPGA device for onboard data analysis and on-the-fly modification of system detection/operating parameters, and capable of collecting and processing data in very small time bins (<1 millisecond) when used in histogramming mode, or in list mode as a list mode MCA.

  16. Generated using version 3.0 of the official AMS LATEX template Computing and Partitioning Cloud Feedbacks using Cloud1

    E-Print Network [OSTI]

    Hartmann, Dennis

    Generated using version 3.0 of the official AMS LATEX template Computing and Partitioning Cloud Feedbacks using Cloud1 Property Histograms.2 Part II: Attribution to the Nature of Cloud Changes3 Mark D-103 Livermore, CA 94551 E-mail: zelinka1@llnl.gov 1 #12;ABSTRACT7 Cloud radiative kernels

  17. Uranium in US surface, ground, and domestic waters. Volume 2

    SciTech Connect (OSTI)

    Drury, J.S.; Reynolds, S.; Owen, P.T.; Ross, R.H.; Ensminger, J.T.

    1981-04-01T23:59:59.000Z

    The report Uranium in US Surface, Ground, and Domestic Waters comprises four volumes. Volumes 2, 3, and 4 contain data characterizing the location, sampling date, type, use, and uranium conentrations of 89,994 individual samples presented in tabular form. The tabular data in volumes 2, 3, and 4 are summarized in volume 1 in narrative form and with maps and histograms.

  18. AN INTRODUCTION TO R DEEPAYAN SARKAR

    E-Print Network [OSTI]

    Bandyopadhyay, Antar

    AN INTRODUCTION TO R DEEPAYAN SARKAR Lattice graphics lattice is an add-on package that implements values using > histogram(~ gcsescore, data = Chem97) Date: October 2011. 1 #12;2 DEEPAYAN SARKAR think is more effective? #12;4 DEEPAYAN SARKAR Basic ideas lattice provides a high-level system

  19. Nonparametric Regression for Geographic Visualization and Analysis of Environmental Policy Gerald Whittaker

    E-Print Network [OSTI]

    Scott, David W.

    Nonparametric Regression for Geographic Visualization and Analysis of Environmental Policy Gerald August 9-13, 1998. The views expressed are the author's, and do not necessarily represent policies; averaged shifted histogram; environmental economics The U.S. Department of Agriculture administers

  20. IOP PUBLISHING NANOTECHNOLOGY Nanotechnology 20 (2009) 255501 (5pp) doi:10.1088/0957-4484/20/25/255501

    E-Print Network [OSTI]

    2009-01-01T23:59:59.000Z

    IOP PUBLISHING NANOTECHNOLOGY Nanotechnology 20 (2009) 255501 (5pp) doi:10. Nanotechnology offers the promise of improved gas sensors with low-power consumption, fast response time which;Nanotechnology 20 (2009) 255501 T Zhang et al Figure 1. AFM images and diameter histograms of CSA-d

  1. Generated using version 3.0 of the official AMS LATEX template Computing and Partitioning Cloud Feedbacks using Cloud1

    E-Print Network [OSTI]

    Hartmann, Dennis

    by adjusting the change in cloud radiative forcing for non-cloud22 related effects as in Soden et al. (2008 planet, the global and annual mean effect40 of clouds at the top of atmosphere (TOA) is to increase Feedbacks using Cloud1 Property Histograms.2 Part I: Cloud Radiative Kernels3 Mark D. Zelinka Department

  2. Assessing deployment strategies for ethanol and flex fuel vehicles in the U.S. light-duty vehicle fleet

    E-Print Network [OSTI]

    McAulay, Jeffrey L. (Jeffrey Lewis)

    2009-01-01T23:59:59.000Z

    Within the next 3-7 years the US light duty fleet and fuel supply will encounter what is commonly referred to as the "blend wall". This phenomenon describes the situation when more ethanol production has been mandated than ...

  3. Linked Deposit Loan Program (Kentucky)

    Broader source: Energy.gov [DOE]

    The Linked Deposit Program provides loan financing for small businesses of up to $100,000 for up to 7 years. The State Investment Commission invests funds from the state's Abandoned Property Cash...

  4. avian flu virus: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    viruses. Our 7 years of AI virus surveillance among water McCracken, Kevin G. 14 Everyday Preventive Actions That Can Help Fight Germs, Like Flu Geosciences Websites Summary:...

  5. Liquefied U.S. Natural Gas Re-Exports to Japan (Million Cubic...

    Annual Energy Outlook 2013 [U.S. Energy Information Administration (EIA)]

    Decade Year-0 Year-1 Year-2 Year-3 Year-4 Year-5 Year-6 Year-7 Year-8 Year-9 2010's 2,822 2,741 5,037 0...

  6. Can Children Notice Ambiguity in a Referential Communication Task: Differences Between Monolingual and Bilingual Children 

    E-Print Network [OSTI]

    Catto, Kerry

    2014-07-01T23:59:59.000Z

    Previous work shows that children are able to perform referential communication tasks successfully but those under 7 years old tend to perform poorer (Bishop & Adams, 1991). On the other hand, adults are very good at referential tasks and especially...

  7. Nevver Stand Stilll Faculty of En

    E-Print Network [OSTI]

    Sekercioglu, Y. Ahmet

    Committee Advisory Committee 6. YEAR IN REVIEW: Projects 11 Garada ­ SAR Formation Flying Project 11 QB50 12 SMiLE 13 Warrawal 14 Biarri 15 7. YEAR IN REVIEW: Workshops & Events 16 Off Earth Mining Forum 16

  8. BIODIVERSITY AND DEVELOPMENT: EUCALYPTUS & FOREST LAW

    E-Print Network [OSTI]

    Gray, Matthew

    in Brazil. Specializations include: Wood construction, Industrialization and marketing of forest products Other: A. 4% to sawmills B. Wood pellets C. system Short rotations of 6-7 years Managed for Fiber or Fuel-wood http

  9. Energy Efficiency and Conservation Block Grant Program

    Broader source: Energy.gov (indexed) [DOE]

    The Native Village of Ouzinkie of Alaska proposes to install a 6 kW solar photovoltaic system on the tribal Administration Building. The building is approximately 7 years...

  10. Liquefied U.S. Natural Gas Re-Exports to Spain (Million Cubic...

    Annual Energy Outlook 2013 [U.S. Energy Information Administration (EIA)]

    Decade Year-0 Year-1 Year-2 Year-3 Year-4 Year-5 Year-6 Year-7 Year-8 Year-9 2000's 0 0 0 2010's 4,117 5,918...

  11. Federal Institutions and the Democratic Transition: Lessons From South Africa

    E-Print Network [OSTI]

    Rubinfeld, Daniel

    2006-01-01T23:59:59.000Z

    ? = 2050 Rand. Technology and Costs (a e , a m , a u ): Theand a u = 7 (years). Technology and Costs (S): The costs perS = 100,000 Rand. Technology and Costs (m): If the central

  12. Plant Disease / March 2002 205205 Phytophthora ramorum as the Cause of Extensive Mortality

    E-Print Network [OSTI]

    California at Berkeley, University of

    of California Cooperative Extension, 1432 Abbott Street, Salinas, CA 93901 Over the past 7 years, a previously been previous reports of high levels of oak mor- tality associated with extended periods of drought

  13. Graduate Program Time Limits and Work Schedules

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    With a bachelor's pursuing a master's degree: 4 years With a bachelor's pursuing a PhD: 7 years With a master's pursuing a second master's degree: 2 years With a master's...

  14. Onsite data processing and monitoring for the Daya Bay Experiment

    E-Print Network [OSTI]

    Ying-Biao Liu; Miao He; Bei-Jiang Liu; Meng Wang; Qiu-Mei Ma; Fa-Zhi Qi; Shan Zeng

    2014-06-09T23:59:59.000Z

    The Daya Bay Reactor Neutrino Experiment started running on September 23, 2011. The offline computing environment, consisting of 11 servers at Daya Bay, was built to process onsite data. With current computing ability, onsite data processing is running smoothly. The Performance Quality Monitoring system (PQM) has been developed to monitor the detector performance and data quality. Its main feature is the ability to efficiently process multi-data-stream from three experimental halls. The PQM processes raw data files from the Daya Bay data acquisition system, generates and publishes histograms via a graphical web interface by executing the user-defined algorithm modules, and saves the histograms for permanent storage. The fact that the whole process takes only around 40 minutes makes it valuable for the shift crew to monitor the running status of all the sub-detectors and the data quality.

  15. Notes on representing grain size distributions obtained by electron backscatter diffraction

    SciTech Connect (OSTI)

    Toth, Laszlo S., E-mail: laszlo.metz@univ-lorraine.fr [Laboratoire d'Etude des Microstructures et de Mécanique des Matériaux (LEM3), UMR 7239, CNRS/Université de Lorraine, F-57045 Metz (France); Laboratory of Excellence on Design of Alloy Metals for low-mAss Structures (DAMAS), Université de Lorraine (France); Biswas, Somjeet, E-mail: somjeetbiswas@gmail.com [Laboratory of Excellence on Design of Alloy Metals for low-mAss Structures (DAMAS), Université de Lorraine (France); Gu, Chengfan, E-mail: chengfan.gu@unsw.edu.au [School of Materials Science and Engineering, The University of New South Wales, Sydney, NSW 2052 (Australia); Beausir, Benoit, E-mail: benoit.beausir@univ-lorraine.fr [Laboratoire d'Etude des Microstructures et de Mécanique des Matériaux (LEM3), UMR 7239, CNRS/Université de Lorraine, F-57045 Metz (France); Laboratory of Excellence on Design of Alloy Metals for low-mAss Structures (DAMAS), Université de Lorraine (France)

    2013-10-15T23:59:59.000Z

    Grain size distributions measured by electron backscatter diffraction are commonly represented by histograms using either number or area fraction definitions. It is shown here that they should be presented in forms of density distribution functions for direct quantitative comparisons between different measurements. Here we make an interpretation of the frequently seen parabolic tales of the area distributions of bimodal grain structures and a transformation formula between the two distributions are given in this paper. - Highlights: • Grain size distributions are represented by density functions. • The parabolic tales corresponds to equal number of grains in a bin of the histogram. • A simple transformation formula is given to number and area weighed distributions. • The particularities of uniform and lognormal distributions are examined.

  16. Probability distribution functions in the finite density lattice QCD

    E-Print Network [OSTI]

    S. Ejiri; Y. Nakagawa; S. Aoki; K. Kanaya; H. Saito; T. Hatsuda; H. Ohno; T. Umeda

    2012-12-04T23:59:59.000Z

    We study the phase structure of QCD at high temperature and density by lattice QCD simulations adopting a histogram method. We try to solve the problems which arise in the numerical study of the finite density QCD, focusing on the probability distribution function (histogram). As a first step, we investigate the quark mass dependence and the chemical potential dependence of the probability distribution function as a function of the Polyakov loop when all quark masses are sufficiently large, and study the properties of the distribution function. The effect from the complex phase of the quark determinant is estimated explicitly. The shape of the distribution function changes with the quark mass and the chemical potential. Through the shape of the distribution, the critical surface which separates the first order transition and crossover regions in the heavy quark region is determined for the 2+1-flavor case.

  17. Application of High-performance Visual Analysis Methods to Laser Wakefield Particle Acceleration Data

    SciTech Connect (OSTI)

    Rubel, Oliver; Prabhat, Mr.; Wu, Kesheng; Childs, Hank; Meredith, Jeremy; Geddes, Cameron G.R.; Cormier-Michel, Estelle; Ahern, Sean; Weber, Gunther H.; Messmer, Peter; Hagen, Hans; Hamann, Bernd; Bethel, E. Wes

    2008-08-28T23:59:59.000Z

    Our work combines and extends techniques from high-performance scientific data management and visualization to enable scientific researchers to gain insight from extremely large, complex, time-varying laser wakefield particle accelerator simulation data. We extend histogram-based parallel coordinates for use in visual information display as well as an interface for guiding and performing data mining operations, which are based upon multi-dimensional and temporal thresholding and data subsetting operations. To achieve very high performance on parallel computing platforms, we leverage FastBit, a state-of-the-art index/query technology, to accelerate data mining and multi-dimensional histogram computation. We show how these techniques are used in practice by scientific researchers to identify, visualize and analyze a particle beam in a large, time-varying dataset.

  18. VAX online System - a modular approach

    SciTech Connect (OSTI)

    White, V.; Constanta-Fanourakis, P.; Heinicke, P.; Petravick, D.; Quigg, L.

    1985-08-01T23:59:59.000Z

    An approach to developing Online Systems for the VAX, under VMS, is described. A framework for integrating separate and diverse programs into a unified whole is described. Included in this is a scheme which permits multiple VAX processes to share the same terminal in an organized way. This makes use of a menu package, (MENCOM), which also permits a command line mode of operation, with dynamic switching between menu and command line mode. A single DISPLAY program can display the histograms of any program in the system, both the in-memory histograms and those previously stored on disk. A centralized message system is designed to handle all error and status messages. A general buffer scheme used to enter data from any input stream and to access data selectively is briefly described. This buffer scheme is covered in more detail, by D. Quarrie in his CDF Data Acquisition System paper, given at this conference.

  19. Statistical density modification using local pattern matching

    SciTech Connect (OSTI)

    Terwilliger, Thomas C.

    2007-01-23T23:59:59.000Z

    A computer implemented method modifies an experimental electron density map. A set of selected known experimental and model electron density maps is provided and standard templates of electron density are created from the selected experimental and model electron density maps by clustering and averaging values of electron density in a spherical region about each point in a grid that defines each selected known experimental and model electron density maps. Histograms are also created from the selected experimental and model electron density maps that relate the value of electron density at the center of each of the spherical regions to a correlation coefficient of a density surrounding each corresponding grid point in each one of the standard templates. The standard templates and the histograms are applied to grid points on the experimental electron density map to form new estimates of electron density at each grid point in the experimental electron density map.

  20. A low power 12-bit ADC for nuclear instrumentation

    SciTech Connect (OSTI)

    Adachi, R.; Landis, D.; Madden, N. [Lawrence Berkeley Lab., CA (United States); Silver, E.; LeGros, M. [Lawrence Livermore National Lab., CA (United States)

    1992-10-01T23:59:59.000Z

    A low power, successive approximation, analog-to-digital converter (ADC) for low rate, low cost, battery powered applications is described. The ADC is based on a commercial 50 mW successive approximation CMOS device (CS5102). An on-chip self-calibration circuit reduces the inherent differential nonlinearity to 7%. A further reduction of the differential nonlinearity to 0.5% is attained with a four bit Gatti function. The Gatti function is distributed to minimize battery power consumption. All analog functions reside with the ADC while the noisy digital functions reside in the personal computer based histogramming memory. Fiber optic cables carry afl digital information between the ADC and the personal computer based histogramming memory.

  1. Generalized-Ensemble Algorithms for Protein Folding Simulations

    E-Print Network [OSTI]

    Yuji Sugita; Ayori Mitsutake; Yuko Okamoto

    2007-07-23T23:59:59.000Z

    Conventional simulations of complex systems in the canonical ensemble suffer from the quasi-ergodicity problem. A simulation in generalized ensemble overcomes this difficulty by performing a random walk in potential energy space and other parameter space. From only one simulation run, one can obtain canonical-ensemble averages of physical quantities as functions of temperature by the single-histogram and/or multiple-histogram reweighting techniques. In this article we review the generalized-ensemble algorithms. Three well-known methods, namely, multicanonical algorithm, simulated tempering, and replica-exchange method, are described first. Both Monte Carlo and molecular dynamics versions of the algorithms are given. We then present further extensions of the above three methods.

  2. Ninth Grade Teachers‘ Perceptions of Cultural Awareness and Teacher Beliefs as Measured by the Cultural Awareness and Beliefs Inventory: Relationship with the Texas Assessment of Knowledge and Skills Reading Scores

    E-Print Network [OSTI]

    Yandell, Shanah Lea

    2011-02-22T23:59:59.000Z

    .................................................................................................. 96 4.2 Normal Q-Q Plot of the Comparative Means of the Ninth Grade Respondents on the CABI ............................................................................. 97 4.3 Histogram of the Comparative Means of the SLC Campuses? Ninth Grade... Q-Q Plot of the Comparative Means of the SLC Campuses? Ninth Grade Respondents on the CABI ......................................................... 102 4.6 Normal Q-Q Plot of the Comparative Means of the THS Campuses? Ninth Grade Respondents...

  3. Curvilinearity in architecture: emotional effect of curvilinear forms in interior design

    E-Print Network [OSTI]

    Madani Nejad, Kayvan

    2007-09-17T23:59:59.000Z

    -8). ....................................................................................60 4.9 Histograms for (Unpleasant-Pleasant) Non-Architects .....................................61 4.10 Normal Q-Q Plot for (Unpleasant-Pleasant) Non-Architects ............................61 4.11 Box Plots for (Unpleasant-Pleasant) Non...-Pleasant) Architects .............................................66 4.14 Normal Q-Q Plot for (Unpleasant-Pleasant) Architects ....................................66 4.15 Box Plots for (Unpleasant-Pleasant) Architects...

  4. Essays in econometrics

    E-Print Network [OSTI]

    Oryshchenko, Vitaliy

    2011-03-15T23:59:59.000Z

    -varying quantiles of GARCH residuals. . . . . . . . . . . 60 2.5 Changing tail dispersion and skewness for GARCH residuals. . . . . . . . 61 2.6 ACFs and histogram of PITs of GARCH residuals. . . . . . . . . . . . . 61 2.7 Smoothed time-varying quantiles of NASDAQ... moving average FDI — foreign direct investment FE — fixed effects GARCH — generalised autoregressive heteroscedasticity GEL — generalised empirical likelihood GELKDE — generalised empirical likelihood-based kernel density estimator GLS — generalised least...

  5. Gammasphere software development. Progress report

    SciTech Connect (OSTI)

    Piercey, R.B.

    1994-01-01T23:59:59.000Z

    This report describes the activities of the nuclear physics group at Mississippi State University which were performed during 1993. Significant progress has been made in the focus areas: chairing the Gammasphere Software Working Group (SWG); assisting with the porting and enhancement of the ORNL UPAK histogramming software package; and developing standard formats for Gammasphere data products. In addition, they have established a new public ftp archive to distribute software and software development tools and information.

  6. Error message recording and reporting in the SLC control system

    SciTech Connect (OSTI)

    Spencer, N.; Bogart, J.; Phinney, N.; Thompson, K.

    1985-04-01T23:59:59.000Z

    Error or information messages that are signaled by control software either in the VAX host computer or the local microprocessor clusters are handled by a dedicated VAX process (PARANOIA). Messages are recorded on disk for further analysis and displayed at the appropriate console. Another VAX process (ERRLOG) can be used to sort, list and histogram various categories of messages. The functions performed by these processes and the algorithms used are discussed.

  7. Error message recording and reporting in the SLC control system

    SciTech Connect (OSTI)

    Spencer, N.; Bogart, J.; Phinney, N.; Thompson, K.

    1985-10-01T23:59:59.000Z

    Error or information messages that are signaled by control software either in the VAX host computer or the local microprocessor clusters are handled by a dedicated VAX process (PARANOIA). Messages are recorded on disk for further analysis and displayed at the appropriate console. Another VAX process (ERRLOG) can be used to sort, list and histogram various categories of messages. The functions performed by these processes and the algorithms used are discussed.

  8. A group-theoretic analysis of symmetric target scattering with application to landmine detection

    E-Print Network [OSTI]

    Stiles, James Marion; Beh, B.; Apte, V.

    2002-08-01T23:59:59.000Z

    STILES et al.: GROUP-THEORETIC ANALYSIS OF SYMMETRIC TARGET SCATTERING 1811 Fig. 6. Histogram of 1094027 41 coefficient values calculated from a set of 2000 bistatic measurements. For a symmetric target (a), most values were much less than one, whereas... is then de- scribed wherein these symmetry measures were calculated from a large collection of bistatic measurements. It is then shown that these values provide an effective scattering feature for classi- fying a subsurface object as either symmetric...

  9. Interrelationships between diet, activity, body composition, and blood pressure in elderly subjects 

    E-Print Network [OSTI]

    Ideno, Katherine Tamiko

    1987-01-01T23:59:59.000Z

    Independent variables which may influence diastolic blood pressure for groups divided by use of ant i- hypertensive drugs, sex, and activity level . . . . . . 99 LIST OF FIGURES FIGURE Page 1 Scatterplot of dietary protein versus caloric in- take from 24...-hour recall 2 Scatterplot of daily caloric expenditure versus age 42 3 Scatterplot of body weight versus abdominal girth 46 4 Histogram showing distribution of sexes within groups divided by activity and use of anti- hypertensive medication 51 5...

  10. The cost effectiveness of geotechnical investigations in commercial building construction

    E-Print Network [OSTI]

    Temple, Merdith Wyndham Bolling

    1985-01-01T23:59:59.000Z

    and conducting thorough geotechnical investigations will be demonstrated. A range estimation and frequency histogram are introduced to illustrate the nominal expense of such studies compared to total project cost. These cost estimation techniques are based... have on project construction costs, particularly with respect to foundation expenditures. This data ". . . is believed by many to hold the key to significant cost reductions in. . . construction programs" . (46). It will be clearly demonstrated...

  11. Development of graphical indices for building energy data

    E-Print Network [OSTI]

    Abbas, Mustafa

    1993-01-01T23:59:59.000Z

    54 55 55 55 . 57 . 59 . 60 Factors That Enhance Graphics. . 1. Distance. 2. Detection. 3. Juxtaposition. 4. Superposition. . 5. Juxtapaging, Indices Development 1. Box and Whisker Plots. 60 61 . 65 71 72 . 72 2. Juxtaposed Pre.... THE INDICES DEVELOPMENT. Indices Development 1. Box and Whisker Plots. 2. Juxtaposed Pre/Post Scatter and BWM Plots. . . . . . 3. 3-D Surface Plots. 4. Carpet Plots with Juxtaposed Histograms. . . . . 5. Coincident Cumulative Frequency Plots. . . . 6...

  12. Emerging Trends with a Significant Impact on the U.S. Intelligence Community 

    E-Print Network [OSTI]

    Stubblefield, Amber; Stockstill, Leah; Westerhof, Emily; Hopper, Eric; Pinones, Zach; Niegelsky, Mark; Mickle, Devon; Davis, Cristina; Rothrock, Caroline

    2014-01-01T23:59:59.000Z

    ) with this outcome is that today, research and development on the study of facial morphology remains in its infancy stages, as the concept of forensic phenotyping is still so new in the world I I of science and genetics.5 5-7 Year Outlook While the current results... images being shown as a hologram. 5-7 Year Outlook Jang-Ung Park at Uslan National Instihite of Science and Technology is currently working towards creating contact lenses that have the same abilities as a computer, including the capability to take photos...

  13. 3DEP in Oregon by the Numbers Expected annual benefits

    E-Print Network [OSTI]

    Torgersen, Christian

    total cost (quality level 2) $32.41 million Payback 0.7 years Quality level 1 buy-up estimate $203DEP in Oregon by the Numbers Expected annual benefits (quality level 2) $45.73 million Estimated resource management; forest resources management; water supply and quality; infrastructure and construction

  14. Further analysis of singular vector and ENSO predictability in the Lamont model--Part I: singular vector and the control

    E-Print Network [OSTI]

    Tang, Youmin

    brings a cooling effect controlling the negative perturbation growth in the central Pacific. Keywords variability in the global climate system. It happens in the tropical Pacific Ocean with a period of 2­7 years and has world-wide climatic, ecological, and social impacts. Significant progress has been made

  15. Low-Cost Hydrogen-from-Ethanol: A Distributed

    E-Print Network [OSTI]

    (Current) (Future-2012) 1 -$ 2 -$ 3 -$ 4 -$ 5 -$ 5-Year catalyst replacement (15% of SMR Capex) 6 175,872$ (175,872)$ 7 -$ 7-year replacement of hot module (12% of Capex) 8 92,775$ 92,775$ 9 -$ 10 -$ SMR (H2A

  16. Job Description Job Title: ORE Marine Research Engineer

    E-Print Network [OSTI]

    Frandsen, Jannette B.

    Job Summary Regular, Full-Time, RCUH Non-Civil Service position with the Ocean & Resource Engineering for a new ocean engineering research and development laboratory focused on ocean observing including sensor. EXPERIENCE: At least seven (7) years of post-graduate experience in ocean engineering design, fabrication

  17. Tetrasomy 8 Detected by Interphase Cytogenetics in a Child with Acute Lymphocytic Leukemia

    E-Print Network [OSTI]

    California at Berkeley, University of

    ELSEVIER Tetrasomy 8 Detected by Interphase Cytogenetics in a Child with Acute Lymphocytic Leukemia is a rare clonal anomaly in human acute leukemia. Here we present a case of a 7-year-old boy 'with acute (trisomy 8) is one of the most common numerical changes observed in acute nonlymphocytic leukemia (ANLL) [1

  18. U.S. Liquefied Natural Gas Imports From Indonesia (Million Cubic...

    Gasoline and Diesel Fuel Update (EIA)

    Decade Year-0 Year-1 Year-2 Year-3 Year-4 Year-5 Year-6 Year-7 Year-8 Year-9 1980's 1,669 1990's 0 0 0 2000's 2,760 0 0 0 0 0 0 0 0 0 2010's...

  19. Facts about ENSO: . Originates in the tropical Pacific

    E-Print Network [OSTI]

    : . Computer models show skill in forecasting tropical Pacific Ocean temperatures one to two years in advance for Pacific Ocean observations that are the foundation of skillful ENSO forecasts: Moored buoys Drifting buoysaaaaaa Facts about ENSO: . Originates in the tropical Pacific . Has a periodicity of 2­7 years

  20. Price of U.S. Liquefied Natural Gas Imports From The United Arab...

    Gasoline and Diesel Fuel Update (EIA)

    Decade Year-0 Year-1 Year-2 Year-3 Year-4 Year-5 Year-6 Year-7 Year-8 Year-9 1990's -- -- -- 3.46 3.74 2.63 3.03 2000's 3.53 -- -- -- -- -- -- -- -- -- 2010's...

  1. Use of Risk-Based End States

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    2010-11-18T23:59:59.000Z

    This 7 year old policy was formulated as part of an effort to better define criteria for when the Office of Environmental Management would be completed with cleanup at DOE sites contaminated by nuclear weapons research, development, and production and nuclear energy research. Based on adherence to existing legislation, the Policy is not necessary.

  2. Price of U.S. Liquefied Natural Gas Imports From Norway (Dollars...

    Gasoline and Diesel Fuel Update (EIA)

    Decade Year-0 Year-1 Year-2 Year-3 Year-4 Year-5 Year-6 Year-7 Year-8 Year-9 2000's -- 9.56 4.45 2010's 5.21 5.97 2.83 14.85 4.47...

  3. March 2013 Senate Update Chair's Report

    E-Print Network [OSTI]

    Jawitz, James W.

    to keep a watch) · Mission Statement is currently in-review with the BOT, they requested additional time take 2-3 years of work. No President's or Provost's Report: Action Items: · The renaming of the Food that language will be removed o County extension faculty will have the 7 year probationary period #12;o Only

  4. Consequences of maternal effects on body and antler size of white-tailed deer By Kevin L. Monteith (B&C Official Measurer), Jonathan A. Jenks (Distinguished Professor,

    E-Print Network [OSTI]

    -quality agricultural crops. Disparity in size of deer between these two areas is probably related to differences comparable husbandry practices. This approach ensured there were no environmental differences influencing for ages up to 7 years. Despite being in good nutritional condition, adult males that originated from

  5. RESEARCH ARTICLE Tapping panel diagnosis, an innovative on-farm decision

    E-Print Network [OSTI]

    Boyer, Edmond

    ). World- wide demand for natural rubber is increasing. Compared with synthetic rubber, the demandRESEARCH ARTICLE Tapping panel diagnosis, an innovative on-farm decision support system for rubber. Latex is produced by the rubber tree (Hevea brasiliensis). Given the 7-year immature unproductive period

  6. Pre-employment Inquiry Form PLEASE PRINT CLEARLY

    E-Print Network [OSTI]

    Rhoads, James

    Pre-employment Inquiry Form PLEASE PRINT CLEARLY and return to your department for processing. ASU: Cell Number: Please list previous addresses for the last 7 years: EMPLOYMENT HISTORY 1. Supervisor Name/Title/Phone: Company: Your Position Title: Location (City, State): Employment Dates: Current Employer: No Yes Do we

  7. Int Psychogeriatr . Author manuscript Does the Framingham Stroke Risk Profile predict white-matter changes in

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    (DTI), we investigated whether the Framingham stroke risk profile (FSRP), a well validated risk participants would show reduced white-matter integrity with higher FSRP, and non-depressed controls (matched with major depression (age 71.8 7.7 years, mean FSRP 10.3 7.6) and 25 controls (age 71.8 7.3 years, mean FSRP

  8. Does Framingham stroke risk profile predict white-matter changes in late-life depression?

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    profile (FSRP), a well validated risk prediction algorithm, is associated with changes in white FSRP, and non-depressed controls (matched for mean vascular risk) would show minimal co-variance with white-matter changes. Methods: 36 participants with major depression (age 71.8±7.7 years, mean FSRP 10

  9. Investigation of Corrosion Damage and Repair System in a Concrete Jetty Structure

    E-Print Network [OSTI]

    Mobasher, Barzin

    Investigation of Corrosion Damage and Repair System in a Concrete Jetty Structure Farid Moradi of the deterioration was reinforcement corrosion, which initiated within few years after the completion of the jetty structure. The structure underwent major corrosion rehabilitation after 7 years of service. Despite the use

  10. Controlled Hydrogen Fleet and Infrastructure Analysis (Presentation)

    SciTech Connect (OSTI)

    Wipke, K.; Sprik, S.; Kurtz, J.; Ramsden, T.; Ainscough, C.; Saur, G.

    2012-05-01T23:59:59.000Z

    This is a presentation about the Fuel Cell Electric Vehicle Learning Demo, a 7-year project and the largest single FCEV and infrastructure demonstration in the world to date. Information such as its approach, technical accomplishments and progress; collaborations and future work are discussed.

  11. Process Design and Optimization of Biorefining Pathways 

    E-Print Network [OSTI]

    Bao, Buping

    2012-07-16T23:59:59.000Z

    of the various techniques developed in this work. The result shows 1, the optimal pathway based on minimum payback period for cost efficiency is pathway through alcohol fermentation and oligomerized to gasoline as 11.7 years with 1620 tonne/day of feedstock...

  12. Unconventional Resources in US: Potential & Lessons Learned

    E-Print Network [OSTI]

    Patzek, Tadeusz W.

    of Barnett Pass, British Columbia, Photo by John McCall Tad Patzek, Petroleum & Geosystems Engineering, UT has been supported in part by a grant from the Sloan Foundation to the Bureau of Economic Geology-7 years from historical wells Work to do: Evaluate wells the average annual gas price starting from when

  13. JOURNAL OF GEOPHYSICAL RESEARCH: OCEANS, VOL. 118, 17591 , doi:10.1002/jgrc.20155, 2013 A three-dimensional eddy census of a high-resolution global

    E-Print Network [OSTI]

    Hamann, Bernd

    JOURNAL OF GEOPHYSICAL RESEARCH: OCEANS, VOL. 118, 1759­1 , doi:10.1002/jgrc.20155, 2013 A three-dimensional eddy census of a high-resolution global ocean simulation Mark R. Petersen,1 Sean J. Williams,1,2 Mathew from a global ocean simulation with one-tenth degree resolution and a duration of 7 years. The census

  14. VETERINARY TEACHING HOSPITAL 1602 Campus Delivery

    E-Print Network [OSTI]

    with 7 or more years' of experience or Associate of Applied Science degree with 7 years' of experience Sciences Position Summary: The Veterinary Teaching Hospital (VTH) at Colorado State University (CSU) seeks of integrity. Superior interpersonal communication and presentation skills as well as proven organizat

  15. The Effect of Music-Assisted Progressive Muscle Relaxation on the Self-Reported Symptoms of Women with Primary Dysmenorrhoea

    E-Print Network [OSTI]

    Memmott, Jenny

    2009-06-02T23:59:59.000Z

    The purpose of this study was to examine the effect of music-assisted progressive muscle relaxation (PMR) on the self-reported symptom scores of women suffering from primary dysmenorrhoea. Twenty-four women with a mean age of 22.7 years participated...

  16. Searching for GRB remnants in nearby galaxies S. G. Bhargavi , J. Rhoads + , R. perna # , J. Feldmeier and J. Greiner

    E-Print Network [OSTI]

    Greiner, Jochen

    : due to the effect of radiation of GRB and its afterglow. The UV afterglow flux of a GRB heats gas, the cooling rate being as slow as #24; 10 5 yrs Slowing remnant : due to the slowing blast­wave. The relativistically expanding blast wave resulting from a GRB explosion takes #24; 10 7 years to slow down and merge

  17. Price of U.S. Liquefied Natural Gas Imports From Egypt (Dollars...

    Annual Energy Outlook 2013 [U.S. Energy Information Administration (EIA)]

    Decade Year-0 Year-1 Year-2 Year-3 Year-4 Year-5 Year-6 Year-7 Year-8 Year-9 2000's -- -- 10.88 6.80 6.83 9.01 3.94 2010's 4.82 5.85 2.52 --...

  18. U.S. Liquefied Natural Gas Imports From Egypt (Million Cubic...

    Gasoline and Diesel Fuel Update (EIA)

    Decade Year-0 Year-1 Year-2 Year-3 Year-4 Year-5 Year-6 Year-7 Year-8 Year-9 2000's 72,540 119,528 114,580 54,839 160,435 2010's 72,990 35,120 2,811 0...

  19. Research Office/Wellcome Trust/13.04.11 Page 1 of 3 Wellcome Trust Investigator Awards

    E-Print Network [OSTI]

    Research Office/Wellcome Trust/13.04.11 Page 1 of 3 Wellcome Trust Investigator Awards Internal's Investigator Awards scheme are available at: http://www.wellcome.ac.uk/Funding/investigator-awards/index.htm 1) Funding available · award value will be in the range of £100k - £425k per year for up to 7 years · only

  20. 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim 663 www.advmat.de

    E-Print Network [OSTI]

    McGehee, Michael

    .[9] These efficiency gains have brought organic solar cells closer to commercial viability, highlighting the importance solar cells that employ P3HT have been well studied,[10­15] however, lifetime studies on the recently extrapolated lifetimes approaching 7 years for encapsulated devices, which is the longest reported lifetime

  1. 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim 1351wileyonlinelibrary.com www.MaterialsViews.com

    E-Print Network [OSTI]

    McGehee, Michael

    8% for polymer-fullerene bulk heterojunction solar cells[4] and a lifetime approaching 7 years was demonstrated for glass encapsulated devices based on polymer-fullerene blends of PCDTBT and PC71BM.[5] However, in order to take full advantage of the cost reductions of organic solar cells from roll- to-roll printing

  2. Image features for misalignment correction in medical flat-detector CT

    SciTech Connect (OSTI)

    Wicklein, Julia; Kunze, Holger; Kalender, Willi A.; Kyriakou, Yiannis [Institute of Medical Physics, University of Erlangen-Nuernberg, Henkestrasse 91, 91052 Erlangen (Germany); Siemens AG, Healthcare Sector, Siemensstrasse 1, 91301 Forchheim (Germany); Institute of Medical Physics, University of Erlangen-Nuernberg, Henkestrasse 91, 91052 Erlangen (Germany); Siemens AG, Healthcare Sector, Siemensstrasse 1, 91301 Forchheim (Germany)

    2012-08-15T23:59:59.000Z

    Purpose: Misalignment artifacts are a serious problem in medical flat-detector computed tomography. Generally, the geometrical parameters, which are essential for reconstruction, are provided by preceding calibration routines. These procedures are time consuming and the later use of stored parameters is sensitive toward external impacts or patient movement. The method of choice in a clinical environment would be a markerless online-calibration procedure that allows flexible scan trajectories and simultaneously corrects misalignment and motion artifacts during the reconstruction process. Therefore, different image features were evaluated according to their capability of quantifying misalignment. Methods: Projections of the FORBILD head and thorax phantoms were simulated. Additionally, acquisitions of a head phantom and patient data were used for evaluation. For the reconstruction different sources and magnitudes of misalignment were introduced in the geometry description. The resulting volumes were analyzed by entropy (based on the gray-level histogram), total variation, Gabor filter texture features, Haralick co-occurrence features, and Tamura texture features. The feature results were compared to the back-projection mismatch of the disturbed geometry. Results: The evaluations demonstrate the ability of several well-established image features to classify misalignment. The authors elaborated the particular suitability of the gray-level histogram-based entropy on identifying misalignment artifacts, after applying an appropriate window level (bone window). Conclusions: Some of the proposed feature extraction algorithms show a strong correlation with the misalignment level. Especially, entropy-based methods showed very good correspondence, with the best of these being the type that uses the gray-level histogram for calculation. This makes it a suitable image feature for online-calibration.

  3. Minijet deformation and charge-independent angular correlations on momentum subspace (eta, phi) in Au-Au collisions at root S-NN=130 GeV

    E-Print Network [OSTI]

    Adams, J.; Aggarwal, M. M.; Ahammed, Z.; Amonett, J.; Anderson, B. D.; Anderson, M.; Arkhipkin, D.; Averichev, G. S.; Bai, Y.; Balewski, J.; Barannikova, O.; Barnby, L. S.; Baudot, J.; Bekele, S.; Belaga, V. V.; Bellingeri-Laurikainen, A.; Bellwied, R.; Bezverkhny, B. I.; Bharadwaj, S.; Bhasin, A.; Bhati, A. K.; Bichsel, H.; Bielcik, J.; Bielcikova, J.; Bland, L. C.; Blyth, C. O.; Blyth, S. -L; Bonner, B. E.; Botje, M.; Bouchet, J.; Brandin, A. V.; Bravar, A.; Bystersky, M.; Cadman, R. V.; Cai, X. Z.; Caines, H.; Sanchez, M. Calderon de la Barca; Castillo, J.; Catu, O.; Cebra, D.; Chajecki, Z.; Chaloupka, P.; Chattopadhyay, S.; Chen, H. F.; Chen, J. H.; Chen, Y.; Cheng, J.; Cherney, M.; Chikanian, A.; Choi, H. A.; Christie, W.; Coffin, J. P.; Cormier, T. M.; Cosentino, M. R.; Cramer, J. G.; Crawford, H. J.; Das, D.; Das, S.; Daugherity, M.; de Moura, M. M.; Dedovich, T. G.; DePhillips, M.; Derevschikov, A. A.; Didenko, L.; Dietel, T.; Djawotho, P.; Dogra, S. M.; Dong, W. J.; Dong, X.; Draper, J. E.; Du, F.; Dunin, V. B.; Dunlop, J. C.; Mazumdar, M. R. Dutta; Eckardt, V.; Edwards, W. R.; Efimov, L. G.; Emelianov, V.; Engelage, J.; Eppley, G.; Erazmus, B.; Estienne, M.; Fachini, P.; Fatemi, R.; Fedorisin, J.; Filimonov, K.; Filip, P.; Finch, E.; Fine, V.; Fisyak, Y.; Fu, J.; Gagliardi, Carl A.; Gaillard, L.; Gans, J.; Ganti, M. S.; Ghazikhanian, V.; Ghosh, P.; Gonzalez, J. E.; Gorbunov, Y. G.; Gos, H.; Grebenyuk, O.; Grosnick, D.; Guertin, S. M.; Guimaraes, K. S. F. F.; Guo, Y.; Gupta, A.; Gutierrez, T. D.; Haag, B.; Hallman, T. J.; Hamed, A.; Harris, J. W.; He, W.; Heinz, M.; Henry, T. W.; Hepplemann, S.; Hippolyte, B.; Hirsch, A.; Hjort, E.; Hoffmann, G. W.; Horner, M. J.; Huang, H. Z.; Huang, S. L.; Hughes, E. W.; Humanic, T. J.; Igo, G.; Ishihara, A.; Jacobs, P.; Jacobs, W. W.; Jakl, P.; Jia, F.; Jiang, H.; Jones, P. G.; Judd, E. G.; Kabana, S.; Kang, K.; Kapitan, J.; Kaplan, M.; Keane, D.; Kechechyan, A.; Khodyrev, V. Yu; Kim, B. C.; Kiryluk, J.; Kisiel, A.; Kislov, E. M.; Klein, S. R.; Koetke, D. D.; Kollegger, T.; Kopytine, M.; Kotchenda, L.; Kouchpil, V.; Kowalik, K. L.; Kramer, M.; Kravtsov, P.; Kravtsov, V. I.; Krueger, K.; Kuhn, C.; Kulikov, A. I.; Kumar, A.; Kuznetsov, A. A.; Lamont, M. A. C.; Landgraf, J. M.; Lange, S.; LaPointe, S.; Laue, F.; Lauret, J.; Lebedev, A.; Lednicky, R.; Lee, C. -H; Lehocka, S.; LeVine, M. J.; Li, C.; Li, Q.; Li, Y.; Lin, G.; Lindenbaum, S. J.; Lisa, M. A.; Liu, F.; Liu, H.; Liu, J.; Liu, L.; Liu, Z.; Ljubicic, T.; Llope, W. J.; Long, H.; Longacre, R. S.; Lopez-Noriega, M.; Love, W. A.; Lu, Y.; Ludlam, T.; Lynn, D.; Ma, G. L.; Ma, J. G.; Ma, Y. G.; Magestro, D.; Mahapatra, D. P.; Majka, R.; Mangotra, L. K.; Manweiler, R.; Margetis, S.; Markert, C.; Martin, L.; Matis, H. S.; Matulenko, Yu A.; McClain, C. J.; McShane, T. S.; Melnick, Yu; Meschanin, A.; Miller, M. L.; Minaev, N. G.; Mioduszewski, Saskia; Mironov, C.; Mischke, A.; Mishra, D. K.; Mitchell, J.; Mohanty, B.; Molnar, L.; Moore, C. F.; Morozov, D. A.; Munhoz, M. G.; Nandi, B. K.; Nattrass, C.; Nayak, T. K.; Nelson, J. M.; Netrakanti, P. K.; Nikitin, V. A.; Nogach, L. V.; Nurushev, S. B.; Odyniec, G.; Ogawa, A.; Okorokov, V.; Oldenburg, M.; Olson, D.; Pachr, M.; Pal, S. K.; Panebratsev, Y.; Panitkin, S. Y.; Pavlinov, A. I.; Pawlak, T.; Peitzmann, T.; Perevoztchikov, V.; Perkins, C.; Peryt, W.; Petrov, V. A.; Phatak, S. C.; Picha, R.; Planinic, M.; Pluta, J.; Poljak, N.; Porile, N.; Porter, J.; Poskanzer, A. M.; Potekhin, M.; Potrebenikova, E.; Potukuchi, B. V. K. S.; Prindle, D.; Pruneau, C.; Putschke, J.; Rakness, G.; Raniwala, R.; Raniwala, S.; Ray, R. L.; Razin, S. V.; Reid, J. G.; Reinnarth, J.; Relyea, D.; Retiere, F.; Ridiger, A.; Ritter, H. G.; Roberts, J. B.; Rogachevskiy, O. V.; Romero, J. L.; Rose, A.; Roy, C.; Ruan, L.; Russcher, M. J.; Sahoo, R.; Sakrejda, I.; Salur, S.; Sandweiss, J.; Sarsour, M.; Sazhin, P. S.; Schambach, J.; Scharenberg, R. P.; Schmitz, N.; Schweda, K.; Seger, J.; Selyuzhenkov, I.; Seyboth, P.; Shabetai, A.; Shahaliev, E.; Shao, M.; Sharma, M.; Shen, W. Q.; Shimanskiy, S. S.; Sichtermann, E.; Simon, F.; Singaraju, R. N.; Smirnov, N.; Snellings, R.; Sood, G.; Sorensen, P.; Sowinski, J.; Speltz, J.; Spinka, H. M.; Srivastava, B.; Stadnik, A.; Stanislaus, T. D. S.; Stock, R.; Stolpovsky, A.; Strikhanov, M.; Stringfellow, B.; Suaide, A. A. P.; Sugarbaker, E.; Sumbera, M.; Sun, Z.; Surrow, B.; Swanger, M.; Symons, T. J. M.; de Toledo, A. Szanto; Tai, A.; Takahashi, J.; Tang, A. H.; Tarnowsky, T.; Thein, D.; Thomas, J. H.; Timmins, A. R.; Timoshenko, S.; Tokarev, M.; Trainor, T. A.; Trentalange, S.; Tribble, Robert E.; Tsai, O. D.; Ulery, J.; Ullrich, T.; Underwood, D. G.; Van Buren, G.; van der Kolk, N.; van Leeuwen, M.; Molen, A. M. Vander; Varma, R.

    2006-01-01T23:59:59.000Z

    METHOD Our eventual goal is to determine the complete structure of the six dimensional, two-particle correlation for all hadron pair charge combinations. Toward this goal the two-particle momentum space was projected onto two, 2D (two dimen- sional... of the correlation data may therefore be simplified without loss of information by 064907-3 J. ADAMS et al. PHYSICAL REVIEW C 73, 064907 (2006) projecting the histograms r?ab onto the difference variables ?1 ? ?2 and ?1 ? ?2 by averaging along directions parallel...

  4. Relationship between suspicious coincidence in natural images and contour-salience in oriented filter responses 

    E-Print Network [OSTI]

    Sarma, Subramonia P.

    2004-09-30T23:59:59.000Z

    The OED derived from the E histograms for six natural images are shown in log-log plot, from a to f. The same images as in Fig. 4 were used. For easier comparison, the curves have been scaled by a factor of 10. We can see that all the curves are mostly... high probabilities, i.e., where h(E) is greater than g(E). Only positive values for E are considered. . . . . . . . . . . . . 20 8 Comparison of OED h(E) of six natural images with their cor- responding normal distributions g(E) of the same variance...

  5. NURE aerial gamma ray and magnetic detail survey of portions of northeast Washington. Final report

    SciTech Connect (OSTI)

    Not Available

    1981-11-01T23:59:59.000Z

    The Northeast Washington Survey was performed under the United States Department of Energy's National Uranium Resource Evaluation (NURE) Program, which is designed to provide radioelement distribution information to assist in assessing the uraniferous material potential of the United States. The radiometric and ancilliary data were digitally recorded and processed. The results are presented in the form of stacked profiles, contour maps, flight path maps, statistical tables and frequency distribution histograms. These graphical outputs are presented at a scale of 1:62,500 and are contained in the individual Volume 2 reports.

  6. Energetic Components of Cooperative Protein Folding

    E-Print Network [OSTI]

    Huseyin Kaya; Hue Sun Chan

    2000-10-11T23:59:59.000Z

    A new lattice protein model with a four-helix bundle ground state is analyzed by a parameter-space Monte Carlo histogram technique to evaluate the effects of an extensive variety of model potentials on folding thermodynamics. Cooperative helical formation and contact energies based on a 5-letter alphabet are found to be insufficient to satisfy calorimetric and other experimental criteria for two-state folding. Such proteinlike behaviors are predicted, however, by models with polypeptide-like local conformational restrictions and environment-dependent hydrogen bonding-like interactions.

  7. Integration of neutron time-of-flight single-crystal Bragg peaks in reciprocal space

    SciTech Connect (OSTI)

    Schultz, Arthur J [ORNL] [ORNL; Joergensen, Mads [ORNL] [ORNL; Wang, Xiaoping [ORNL] [ORNL; Mikkelson, Ruth L [ORNL] [ORNL; Mikkelson, Dennis J [ORNL] [ORNL; Lynch, Vickie E [ORNL] [ORNL; Peterson, Peter F [ORNL] [ORNL; Green, Mark L [ORNL] [ORNL; Hoffmann, Christina [ORNL] [ORNL

    2014-01-01T23:59:59.000Z

    The intensity of single crystal Bragg peaks obtained by mapping neutron time-of-flight event data into reciprocal space and integrating in various ways are compared. These include spherical integration with a fixed radius, ellipsoid fitting and integrating of the peak intensity and one-dimensional peak profile fitting. In comparison to intensities obtained by integrating in real detector histogram space, the data integrated in reciprocal space results in better agreement factors and more accurate atomic parameters. Furthermore, structure refinement using integrated intensities from one-dimensional profile fitting is demonstrated to be more accurate than simple peak-minus-background integration.

  8. Discoveries far from the lamppost with matrix elements and ranking

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Debnath, Dipsikha; Gainer, James S.; Matchev, Konstantin T.

    2015-04-01T23:59:59.000Z

    The prevalence of null results in searches for new physics at the LHC motivates the effort to make these searches as model-independent as possible. We describe procedures for adapting the Matrix Element Method for situations where the signal hypothesis is not known a priori. We also present general and intuitive approaches for performing analyses and presenting results, which involve the flattening of background distributions using likelihood information. The first flattening method involves ranking events by background matrix element, the second involves quantile binning with respect to likelihood (and other) variables, and the third method involves reweighting histograms by the inverse of the background distribution.

  9. Development of a small angle hadron calorimeter prototype for the Collider Detector at Fermilab

    E-Print Network [OSTI]

    Thane, John Mark

    1989-01-01T23:59:59.000Z

    that very little shower development would occur within our calorimeter resulting in an almost fiat longitudinal shower profile. At the M'Test beam site at FNAL, we set the calorimeter halves up so that all four chambers would intercept the same particie... of the shower development in a total absorption calorimeter. The histograms in Figure 10 show the longitudinal development of the hsdronic shower as seen by the calorimeter. In Table 2, we look at the efficiency measured in the test beam ss the ratio...

  10. Characterization of the Germania Spraberry unit from analog studies and cased-hole neutron log data

    E-Print Network [OSTI]

    Olumide, Babajide Adelekan

    2005-11-01T23:59:59.000Z

    Crossplot for lithology identification in 1U sand for well ET 37..?.?? 23 2.6b Crossplot for lithology identification in 5U sand for well ET 37...??? 23 3.1 Minimum gamma ray values for ET O?Daniel unit in the 1U sand interval...??????????????????????.?... 26 3.2 Maximum gamma ray values for ET O?Daniel unit in the 1U sand interval??????????????????????..?.. 27 3.3 Variations in response from the gamma ray curves in ET O?Daniel??.. 28 3.4 Histogram and CDF for wells 36, before and after normalizing...

  11. Asymptotics for the maximum likelihood estimators of diffusion models

    E-Print Network [OSTI]

    Jeong, Minsoo

    2009-05-15T23:59:59.000Z

    : : : : : : 24 3 First Order Distribution and the Histogram of t(^fi2) { CEV : : : : : 25 4 First Order Distributions of t(^fi1) and t(^fi2) : : : : : : : : : : : : : : 33 1 CHAPTER I INTRODUCTION The difiusion model was originally designed and has long been used... of the estimator. Wooldridge (1994) shows that AD3 together with AD1 and AD2 implies1 AD4: S(^ ) = 0 with probability approaching to one as T !1 and ? ! 0. AD5: w?1?H(~ )?H( 0)?w?10= op(1) and w0(^ ? 0) = Op(1). Thus, with these conditions, we have w?1S(^ ) = w?1S...

  12. Lee-Yang Zeroes and Logarithmic Corrections in the $?^4_4$ Theory

    E-Print Network [OSTI]

    R. Kenna; C. B. Lang

    1992-10-13T23:59:59.000Z

    The leading mean-field critical behaviour of $\\phi^4_4$-theory is modified by multiplicative logarithmic corrections. We analyse these corrections both analytically and numerically. In particular we present a finite-size scaling theory for the Lee-Yang zeroes and temperature zeroes, both of which exhibit logarithmic corrections. On lattices from size $8^4$ to $24^4$, Monte-Carlo cluster methods and multi-histogram techniques are used to determine the partition function zeroes closest to the critical point. Finite-size scaling behaviour is verified and the logarithmic corrections are found to be in good agreement with our analytical predictions.

  13. MARS15 overview

    SciTech Connect (OSTI)

    Mokhov, N.V.; Striganov, S.I.; /Fermilab

    2007-01-01T23:59:59.000Z

    MARS15 is a Monte Carlo code for inclusive and exclusive simulation of three-dimensional hadronic and electromagnetic cascades, muon, heavy-ion, and low-energy neutron transport in accelerator, detector, spacecraft, and shielding components in the energy range from a fraction of an electronvolt up to 100 TeV. Main features of the code are described in this paper with a focus on recent developments and benchmarking. Newest developments concern inclusive and exclusive nuclear event generators, extended particle list in both modes, heavy-ion capability, electromagnetic interactions, enhanced geometry, tracking, histogramming and residual dose modules, improved graphical-user interface, and other external interfaces.

  14. Determination of the paradihlorobenzene and paradibromobenzene solid solutions nanoparticles structure via Raman spectra

    E-Print Network [OSTI]

    Korshunov, M A

    2012-01-01T23:59:59.000Z

    We measured the small frequencies Raman spectrum of the paradihlorobenzene and paradihlorobenzene solid solution nanoparticles with the size about 100 nanometers. Values of frequencies of lines decrease. The size of nanoparticles was determined by the electronic microscope. Calculations of nanoparticles structure were done using the method of molecular dynamics and histograms of nanoparticles spectra were calculated via the Dyne's method. The result is that the Raman spectrum is the sum of spectra from the central part of the nanoparticle and superficial structures with smaller concentration of paradihlorobenzene.

  15. Lightning Strikes on Airborne Grounded Systems

    E-Print Network [OSTI]

    Malinga, Gilbert Aporu

    2014-10-13T23:59:59.000Z

    LIST OF FIGURES Page Fig. 1-1 Histogram of the average wind speed over a 10 year period at an elevation of a) sH ? 100 m and b) sH ? 600 m, above the mean water level at Montauk, New York. Wind data accessed from the National Buoy Data Center.... The destructive power of lightning discharges to both land-based and airborne systems that cannot adequately dissipate large impulses of energy is well documented (Miyake et al., 1990; Sorensen et al., 1998; Uman and Rakov, 2003). Lightning discharges can...

  16. Acoustic emission signals resulting from the drying induced fractures of Phyllostachys Pubescens bamboo, Evidence of scale free phenomena

    E-Print Network [OSTI]

    Gabriel Villalobos

    2015-03-15T23:59:59.000Z

    I have performed experimental measurements of acoustic emission signals resulting from the drying process of Phyllostachys Pubescens bamboo. The emphasis was on identifying individual events, and characterize them according to their time span and energy release. My results show a histogram of experimental squared voltage distributions nicely fit into a power law with exponent of $-1.16$, reminiscent of scale free phenomena. I have also calculated the average signal shape, for different time spans of the system, and found an asymmetrical form. The experimental evidence points to the system having an isolated large crack at the beginning of the simulation.

  17. Detection of pulse modulated signals by means of the level-crossing rate

    E-Print Network [OSTI]

    Boatright, Paul Ashton

    1972-01-01T23:59:59.000Z

    , Gaussian noise and for noise alone. The system for obtaining the histograms consists of special purpose 10 equipment that measures N(o;T) and inputs the results of each counting period directly into a Hewlett-Packard 2114B mini-computer. Prom this data.... It is convenient to use a compact matrix notation for express- ing higher order probability density functions. Therefore (2. 41) is rewritten as T T E(C2) = J (4E2)M(~) 66exp- ( Y'M Y )/2) dudvdBd6 [2. 42] 0 0 0 0 Y' = transpose Y = row vector (y(u), y(u}, y...

  18. Diphoton production at hadron colliders: a fully-differential QCD calculation at NNLO

    E-Print Network [OSTI]

    Stefano Catani; Leandro Cieri; Daniel de Florian; Giancarlo Ferrera; Massimiliano Grazzini

    2011-10-11T23:59:59.000Z

    We consider direct diphoton production in hadron collisions, and we compute the next-to-next-to-leading order (NNLO) QCD radiative corrections at the fully-differential level. Our calculation uses the $q_T$ subtraction formalism and it is implemented in a parton level Monte Carlo program. The program allows the user to apply arbitrary kinematical cuts on the final-state photons and the associated jet activity, and to compute the corresponding distributions in the form of bin histograms. We present selected numerical results related to Higgs boson searches at the LHC and corresponding results at the Tevatron.

  19. Discoveries far from the lamppost with matrix elements and ranking

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Debnath, Dipsikha; Gainer, James S.; Matchev, Konstantin T.

    2015-04-01T23:59:59.000Z

    The prevalence of null results in searches for new physics at the LHC motivates the effort to make these searches as model-independent as possible. We describe procedures for adapting the Matrix Element Method for situations where the signal hypothesis is not known a priori. We also present general and intuitive approaches for performing analyses and presenting results, which involve the flattening of background distributions using likelihood information. The first flattening method involves ranking events by background matrix element, the second involves quantile binning with respect to likelihood (and other) variables, and the third method involves reweighting histograms by the inversemore »of the background distribution.« less

  20. Long-term performance of the Hunn passive solar residence

    SciTech Connect (OSTI)

    Hunn, B.D.

    1981-01-01T23:59:59.000Z

    Detailed performance and annual energy consumption data are reported, as well as occupant observations and conclusions, for three heating seasons in the Hunn hybrid passive/active solar residence located in Los Alamos, New Mexico. The performance data were gathered by the Los Alamos National Laboratory and include hourly storage wall and interior temperature data for a midwinter period, an interior air-temperature histogram, and measured auxiliary energy consumption and solar heating fraction for each heating season. Also, energy and cost savings over the three-year period are estimated.

  1. Maximum Entropy Models of Shortest Path and Outbreak Distributions in Networks

    E-Print Network [OSTI]

    Bauckhage, Christian; Hadiji, Fabian

    2015-01-01T23:59:59.000Z

    Properties of networks are often characterized in terms of features such as node degree distributions, average path lengths, diameters, or clustering coefficients. Here, we study shortest path length distributions. On the one hand, average as well as maximum distances can be determined therefrom; on the other hand, they are closely related to the dynamics of network spreading processes. Because of the combinatorial nature of networks, we apply maximum entropy arguments to derive a general, physically plausible model. In particular, we establish the generalized Gamma distribution as a continuous characterization of shortest path length histograms of networks or arbitrary topology. Experimental evaluations corroborate our theoretical results.

  2. Robust estimation of the parameters of a disturbed non-stationary Gaussian process

    E-Print Network [OSTI]

    Sergio Frasca; Pia Astone

    2009-05-15T23:59:59.000Z

    A typical problem in the detection of the gravitational waves in the data of gravitational antennas is the non-stationarity of the Gaussian noise (and so the varying sensitivity) and the presence of big impulsive disturbances. In such conditions the estimation of the standard deviation of the Gaussian process done with a classical estimator applied after a "rough" cleaning of the big pulses often gives poor results. We propose a method based on a matched filter applied to an AR histogram of the absolute value of the data

  3. Simple flexible polymers in a spherical cage

    E-Print Network [OSTI]

    M. Marenz; J. Zierenberg; H. Arkin; W. Janke

    2012-12-26T23:59:59.000Z

    We report the results of Monte Carlo simulations investigating the effect of a spherical confinement within a simple model for a flexible homopolymer. We use the parallel tempering method combined with multi-histogram reweighting analysis and multicanonical simulations to investigate thermodynamical observables over a broad range of temperatures, which enables us to describe the behavior of the polymer and to locate the freezing and collapse transitions. We find a strong effect of the spherical confinement on the location of the collapse transition, whereas the freezing transition is hardly effected.

  4. Portable Gathering System for Monitoring and Online Calibration at ATLAS

    E-Print Network [OSTI]

    Conde-Muíño, P; Dos Anjos, A; Baines, J T M; Bee, C P; Biglietti, M; Bogaerts, J A C; Boisvert, V; Bosman, M; Caron, B; Casado, M P; Cataldi, G; Cavalli, D; Cervetto, M; Comune, G; De Santo, A; Díaz-Gómez, M; Dosil, M; Ellis, Nick; Emeliyanov, D; Epp, B; Falciano, S; Farilla, A; George, S; Ghete, V M; González, S; Grothe, M; Kabana, S; Khomich, A; Kilvington, G; Konstantinidis, N P; Kootz, A; Lowe, A; Luminari, L; Maeno, T; Masik, J; Di Mattia, A; Meessen, C; Mello, A G; Merino, G; Moore, R; Morettini, P; Negri, A; Nikitin, N V; Nisati, A; Padilla, C; Panikashvili, N; Parodi, F; Pérez-Réale, V; Pinfold, J L; Pinto, P; Qian, Z; Resconi, S; Rosati, S; Sánchez, C; Santamarina-Rios, C; Scannicchio, D A; Schiavi, C; Segura, E; De Seixas, J M; Sivoklokov, S Yu; Soluk, R A; Stefanidis, E; Sushkov, S; Sutton, M; Tapprogge, Stefan; Thomas, E; Touchard, F; Venda-Pinto, B; Vercesi, V; Werner, P; Wheeler, S; Wickens, F J; Wiedenmann, W; Wielers, M; Zobernig, G; Computing In High Energy Physics

    2005-01-01T23:59:59.000Z

    During the runtime of any experiment, a central monitoring system that detects problems as soon as they appear has an essential role. In a large experiment, like ATLAS, the online data acquisition system is distributed across the nodes of large farms, each of them running several processes that analyse a fraction of the events. In this architecture, it is necessary to have a central process that collects all the monitoring data from the different nodes, produces full statistics histograms and analyses them. In this paper we present the design of such a system, called the gatherer. It allows to collect any monitoring object, such as histograms, from the farm nodes, from any process in the DAQ, trigger and reconstruction chain. It also adds up the statistics, if required, and processes user defined algorithms in order to analyse the monitoring data. The results are sent to a centralized display, that shows the information online, and to the archiving system, triggering alarms in case of problems. The innovation...

  5. Local Delivery System of Immune Modulating Drug for Unresectable Adenocarcinoma: In Vitro Experimental Study and In Vivo Animal Study

    SciTech Connect (OSTI)

    Lee, Don Haeng [Inha University, College of Medicine, Department of Internal Medicine (Korea, Republic of); Kang, Sung-Gwon [Seoul National University Bundang Hospital, Department of Diagnostic Radiology (Korea, Republic of)], E-mail: gangsg@radiol.snu.ac.kr; Jeong, Seok [Inha University, College of Medicine, Department of Internal Medicine (Korea, Republic of); Yoon, Chang Jin; Choi, Jung-Ah [Seoul National University Bundang Hospital, Department of Diagnostic Radiology (Korea, Republic of); Byun, Ju Nam [Chosun University, College of Medicine, Department of Radiology (Korea, Republic of); Park, Jae Hyung [Seoul National University Bundang Hospital, Department of Diagnostic Radiology (Korea, Republic of); Lee, Kyu Back [Korea University, College of Medicine, Department of Biomedical Engineering (Korea, Republic of)

    2006-10-15T23:59:59.000Z

    The purpose of the study was to evaluate the efficacy and safety of a developed drug delivery system containing OK-432 through in vitro and animal study. An OK-432-impregnated polycarbonate/polyurethane stent membrane was used to develop a drug delivery system (DDS) enabling the locoregional release of OK-432. Polyethyleneglycol was used as a detergent and porosity generator. The stability of OK-432 in solvent, releasing kinetics of drug, and cytotoxicity of the DDS were evaluated. OK-432-impregnated DDS was implanted in mice in which a human adenocarcinoma cell line was injected and grown in their back. Flow cytometry and enzyme-linked immunosorbent assay were used for quantifying the amount of drug. OK-432 exposed to phosphate-buffered saline and OK-432 exposed to N,N-dimethylacetamide showed similar results on dot graphs and histograms. However, OK-432 exposed to tetrahydrofurane showed different dot graphs and histograms, which means that the antigenicity of the drug was changed. The release rate of OK-432 was maintained at a constant level for 6 weeks. The local delivery of OK-432 was found to have an antitumor effect on a human adenocarcinoma cell line in an animal study, but no effect on this cell line in in vitro cell culture. Histologic examination showed minimal inflammatory reaction in surrounding tissue. Our study shows that local treatment using this OK-432 release system is safe and effective in reducing adenocarcinoma in a mouse model.

  6. Response of a depleted sagebrush steppe riparian system to grazing control and woody plantings. Forest Service research paper

    SciTech Connect (OSTI)

    Clary, W.P.; Shaw, N.L.; Dudley, J.G.; Saab, V.A.; Kinney, J.W.

    1996-12-01T23:59:59.000Z

    To find out if a depleted riparian system in the sagebrush steppe of eastern Oregon would respond quickly to improved management, five management treatments were applied for 7 years, ranging from ungrazed to heavily grazed treatments, including, in some cases, planting of woody species. While the results varied, all treatments were too limited to significantly restore the damaged areas within the 7-year span. Although some improvements were made in woody plant densities, little meaningful change occurred in the frequencies of herbaceous wetland plants, densities of small wildlife, or stream channel morphology. We concluded the restoration would take many years, possibly decades, without increased revegetation efforts and continued reductions in grazing in this riparian system damaged over 150 years.

  7. TFE design package final report, TFE Verification Program

    SciTech Connect (OSTI)

    Not Available

    1994-06-01T23:59:59.000Z

    The program objective is to demonstrate the technology readiness of a TFE suitable for use as the basic element in a thermionic reactor with electric power output in the 0.5 to 5.0 MW(e) range, and a full-power life of 7 years. A TFE for a megawatt class system is described. Only six cells are considered for simplicity; a megawatt class TFE would have many more cells, the exact number dependent on optimization trade studies.

  8. Employment at National Laboratories

    SciTech Connect (OSTI)

    E. S. Peterson; C. A. Allen

    2007-04-01T23:59:59.000Z

    Scientists enter the National Laboratory System for many different reasons. For some, faculty positions are scarce, so they take staff-scientist position at national laboratories (i.e. Pacific Northwest, Idaho, Los Alamos, and Brookhaven). Many plan to work at the National Laboratory for 5 to 7 years and then seek an academic post. For many (these authors included), before they know it it’s 15 or 20 years later and they never seriously considered leaving the laboratory system.

  9. Space nuclear power and man's extraterrestrial civilization

    SciTech Connect (OSTI)

    Angelo, J.J.; Buden, D.

    1983-01-01T23:59:59.000Z

    This paper examines leading space nuclear power technology candidates. Particular emphasis is given the heat-pipe reactor technology currently under development at the Los Alamos National Laboratory. This program is aimed at developing a 10-100 kWe, 7-year lifetime space nuclear power plant. As the demand for space-based power reaches megawatt levels, other nuclear reactor designs including: solid core, fluidized bed, and gaseous core, are considered.

  10. 1997 DRY BEAN VARIETY CANNING TRIALS MICHIGAN DRY BEAN PRODUCTION RESEARCH ADVISORY BOARD

    E-Print Network [OSTI]

    1997 DRY BEAN VARIETY CANNING TRIALS MICHIGAN DRY BEAN PRODUCTION RESEARCH ADVISORY BOARD Rating 1=poor, 2=fair, 3=good, 4=above average, 5=excellent NAVY LIGHT RED KIDNEY BEANS VARIETY GRATIOT HURON 8.4 3.3 ASG96YT8 2.1 1.8 DARK RED KIDNEY BEANS ASG96YT37 3.4 2.1 VARIETY MONTCALM BAY 7 YEAR AVE ASG96YT

  11. The Solar Wind Energy Flux

    E-Print Network [OSTI]

    Chat, G Le; Meyer-Vernet, N

    2012-01-01T23:59:59.000Z

    The solar-wind energy flux measured near the ecliptic is known to be independent of the solar-wind speed. Using plasma data from Helios, Ulysses, and Wind covering a large range of latitudes and time, we show that the solar-wind energy flux is independent of the solar-wind speed and latitude within 10%, and that this quantity varies weakly over the solar cycle. In other words the energy flux appears as a global solar constant. We also show that the very high speed solar-wind (VSW > 700 km/s) has the same mean energy flux as the slower wind (VSW < 700 km/s), but with a different histogram. We use this result to deduce a relation between the solar-wind speed and density, which formalizes the anti-correlation between these quantities.

  12. Combustion Process in a Spark Ignition Engine: Analysis of Cyclic Maximum Pressure and Peak Pressure Angle

    E-Print Network [OSTI]

    G. Litak; T. Kaminski; J. Czarnigowski; A. K. Sen; M. Wendeker

    2006-11-29T23:59:59.000Z

    In this paper we analyze the cycle-to-cycle variations of maximum pressure $p_{max}$ and peak pressure angle $\\alpha_{pmax}$ in a four-cylinder spark ignition engine. We examine the experimental time series of $p_{max}$ and $\\alpha_{pmax}$ for three different spark advance angles. Using standard statistical techniques such as return maps and histograms we show that depending on the spark advance angle, there are significant differences in the fluctuations of $p_{max}$ and $\\alpha_{pmax}$. We also calculate the multiscale entropy of the various time series to estimate the effect of randomness in these fluctuations. Finally, we explain how the information on both $p_{max}$ and $\\alpha_{pmax}$ can be used to develop optimal strategies for controlling the combustion process and improving engine performance.

  13. mc4qcd: Online Analysis Tool for Lattice QCD

    E-Print Network [OSTI]

    Massimo Di Pierro; Yaoqian Zhong; Brian Schinazi

    2010-05-19T23:59:59.000Z

    mc4qcd is a web based collaboration tool for analysis of Lattice QCD data. Lattice QCD computations consists of a large scale Markov Chain Monte Carlo. Multiple measurements are performed at each MC step. Our system acquires the data by uploading log files, parses them for results of measurements, filters the data, mines for required information by aggregating results, represents the results as plots and histograms, and it further allows refining and interaction by fitting the results. The system computes moving averages and autocorrelations, builds bootstrap samples and bootstrap errors, and allows modeling the data using Bayesian correlated constrained linear and non-linear fits. It can be scripted to allow real time visualization of results form an ongoing computation. The system is modular and it can be adapted to automating the analysis workflow of different types of MC computations.

  14. Geostatistical Simulation of Hydrofacies Heterogeneity of the West Thessaly Aquifer Systems in Greece

    SciTech Connect (OSTI)

    Modis, K., E-mail: kmodis@mail.ntua.gr; Sideri, D. [National Technical University of Athens, School of Mining and Metallurgical Engineering (Greece)] [National Technical University of Athens, School of Mining and Metallurgical Engineering (Greece)

    2013-06-15T23:59:59.000Z

    Integrating geological properties, such as relative positions and proportions of different hydrofacies, is of highest importance in order to render realistic geological patterns. Sequential indicator simulation (SIS) and Plurigaussian simulation (PS) are alternative methods for conceptual and deterministic modeling for the characterization of hydrofacies distribution. In this work, we studied the spatial differentiation of hydrofacies in the alluvial aquifer system of West Thessaly basin in Greece. For this, we applied both SIS and PS techniques to an extensive set of borehole data from that basin. Histograms of model versus experimental hydrofacies proportions and indicative cross sections were plotted in order to validate the results. The PS technique was shown to be more effective in reproducing the spatial characteristics of the different hydrofacies and their distribution across the study area. In addition, the permeability differentiations reflected in the PS model are in accordance to known heterogeneities of the aquifer capacity.

  15. Sampling Free Energy Surfaces as Slices by Combining Umbrella Sampling and Metadynamics

    E-Print Network [OSTI]

    Kapil, Venkat; Nair, Nisanth N

    2015-01-01T23:59:59.000Z

    Metadynamics (MTD) is a very powerful technique to sample high--dimensional free energy landscapes, and due to its self--guiding property, the method has been successful in studying complex reactions and conformational changes.MTD sampling is based on filling the free energy basins by biasing potentials and thus for cases with flat, broad and unbound free energy wells, the computational time to sample them becomes very large.To alleviate this problem, we propose a scheme, named Well--Sliced MTD (WS--MTD), where we combine the standard Umbrella Sampling (US) technique with MTD to sample orthogonal collective variables (CVs) in a simultaneous way. Within this scheme, we construct the equilibrium distribution of CVs from biased distributions obtained from independent MTD simulations with umbrella potentials. Reweighting is carried out by a procedure that combines US reweighting and Tiwary-Parrinello metadynamics reweighting within the Weighted Histogram Analysis Method (WHAM). WS--MTD will be an ideal strategy f...

  16. Multiple time scale blinking in InAs quantum dot single-photon sources

    E-Print Network [OSTI]

    Marcelo Davanco; C. Stephen Hellberg; Serkan Ates; Antonio Badolato; Kartik Srinivasan

    2014-04-21T23:59:59.000Z

    We use photon correlation measurements to study blinking in single, epitaxially-grown self-assembled InAs quantum dots situated in circular Bragg grating and microdisk cavities. The normalized second-order correlation function g(2)(\\tau) is studied across eleven orders of magnitude in time, and shows signatures of blinking over timescales ranging from tens of nanoseconds to tens of milliseconds. The g(2)(\\tau) data is fit to a multi-level system rate equation model that includes multiple non-radiating (dark) states, from which radiative quantum yields significantly less than 1 are obtained. This behavior is observed even in situations for which a direct histogramming analysis of the emission time-trace data produces inconclusive results.

  17. On Comparing the Quality of Head and Neck Imrt Plans Delivered with Two Different Linear Accelerator Manufacturers

    SciTech Connect (OSTI)

    Basran, Parminder S., E-mail: pbasran@bccancer.bc.c [Department of Medical Physics, Odette Cancer Centre, Toronto, Ontario (Canada); Department of Radiation Oncology, University of Toronto, Toronto, Ontario (Canada); Balogh, Judith; Poon, Ian; MacKenzie, Robert [Department of Radiation Oncology, University of Toronto, Toronto, Ontario (Canada); Department of Radiation Oncology, Odette Cancer Centre, Toronto, Ontario (Canada); Chan, Timothy [Department of Medical Sciences, University of Western Ontario, Toronto, Ontario (Canada)

    2011-04-01T23:59:59.000Z

    The purpose of this work was to determine whether 2 different types of linear accelerators manufacturers with similar MLC leaf widths deliver equivalent IMRT distributions for head and neck radiotherapy patients. In this study, plans delivered with Siemens linacs were re-optimized with an Elekta linac and vice versa. To test for significance, paired t-tests were computed to examine differences in target and normal tissue doses and monitor units. Dose distributions, dose-volume histograms, and dose to targets and normal tissues were found to be equivalent irrespective of the linac type. However, approximately 15% more monitor units were delivered when planned on the Elekta machine (p < 0.002). Both linear accelerators provide plans of comparable dosimetric quality; however, Elekta machines deliver slightly more monitor units than Siemens machines. This increase is likely due differences in geometric properties of the machine head designs, as modeled in the treatment planning system.

  18. High Performance Multivariate Visual Data Exploration for Extremely Large Data

    SciTech Connect (OSTI)

    Rubel, Oliver; Wu, Kesheng; Childs, Hank; Meredith, Jeremy; Geddes, Cameron G.R.; Cormier-Michel, Estelle; Ahern, Sean; Weber, Gunther H.; Messmer, Peter; Hagen, Hans; Hamann, Bernd; Bethel, E. Wes; Prabhat,

    2008-08-22T23:59:59.000Z

    One of the central challenges in modern science is the need to quickly derive knowledge and understanding from large, complex collections of data. We present a new approach that deals with this challenge by combining and extending techniques from high performance visual data analysis and scientific data management. This approach is demonstrated within the context of gaining insight from complex, time-varying datasets produced by a laser wakefield accelerator simulation. Our approach leverages histogram-based parallel coordinates for both visual information display as well as a vehicle for guiding a data mining operation. Data extraction and subsetting are implemented with state-of-the-art index/query technology. This approach, while applied here to accelerator science, is generally applicable to a broad set of science applications, and is implemented in a production-quality visual data analysis infrastructure. We conduct a detailed performance analysis and demonstrate good scalability on a distributed memory Cray XT4 system.

  19. Analysis of heat release dynamics in an internal combustion engine using multifractals and wavelets

    SciTech Connect (OSTI)

    Sen, Asok K [Indiana University; Litak, Grzegorz [Technical University of Lublin; FINNEY, Charles E A [ORNL; Daw, C Stuart [ORNL; Wagner, Robert M [ORNL

    2010-01-01T23:59:59.000Z

    In this paper we analyze data from previously reported experimental measurements of cycle-to-cycle combustion variations in a lean-fueled, multi-cylinder spark-ignition (SI) engine. We characterize the changes in the observed combustion dynamics with as-fed fuel air ratio using conventional histograms and statistical moments, and we further characterize the shifts in combustion complexity in terms of multifractals and wavelet decomposition. Changes in the conventional statistics and multifractal structure indicate trends with fuel air ratio that parallel earlier reported observations. Wavelet decompositions reveal persistent, non-stochastic oscillation modes at higher fuel air ratios that were not obvious in previous analyses. Recognition of these long-time-scale, non-stochastic oscillations is expected to be useful for improving modelling and control of engine combustion variations and multi-cylinder balancing.

  20. Planck intermediate results. XXXV. Probing the role of the magnetic field in the formation of structure in molecular clouds

    E-Print Network [OSTI]

    Ade, P A R; Alves, M I R; Arnaud, M; Arzoumanian, D; Ashdown, M; Aumont, J; Baccigalupi, C; Banday, A J; Barreiro, R B; Bartolo, N; Battaner, E; Benabed, K; Benoît, A; Benoit-Lévy, A; Bernard, J -P; Bersanelli, M; Bielewicz, P; Bock, J J; Bonavera, L; Bond, J R; Borrill, J; Bouchet, F R; Boulanger, F; Bracco, A; Burigana, C; Calabrese, E; Cardoso, J -F; Catalano, A; Chiang, H C; Christensen, P R; Colombo, L P L; Combet, C; Couchot, F; Crill, B P; Curto, A; Cuttaia, F; Danese, L; Davies, R D; Davis, R J; de Bernardis, P; de Rosa, A; de Zotti, G; Delabrouille, J; Dickinson, C; Diego, J M; Dole, H; Donzelli, S; Doré, O; Douspis, M; Ducout, A; Dupac, X; Efstathiou, G; Elsner, F; Enßlin, T A; Eriksen, H K; Falgarone, E; Ferrière, K; Finelli, F; Forni, O; Frailis, M; Fraisse, A A; Franceschi, E; Frejsel, A; Galeotta, S; Galli, S; Ganga, K; Ghosh, T; Giard, M; Gjerløw, E; González-Nuevo, J; Górski, K M; Gregorio, A; Gruppuso, A; Gudmundsson, J E; Guillet, V; Harrison, D L; Helou, G; Henrot-Versillé, S; Hernández-Monteagudo, C; Herranz, D; Hildebrandt, S R; Hivon, E; Holmes, W A; Hornstrup, A; Huffenberger, K M; Hurier, G; Jaffe, A H; Jaffe, T R; Jones, W C; Juvela, M; Keihänen, E; Keskitalo, R; Kisner, T S; Knoche, J; Kunz, M; Kurki-Suonio, H; Lagache, G; Lamarre, J -M; Lasenby, A; Lattanzi, M; Lawrence, C R; Leonardi, R; Levrier, F; Liguori, M; Lilje, P B; Linden-Vørnle, M; López-Caniego, M; Lubin, P M; Macías-Pérez, J F; Maino, D; Mandolesi, N; Mangilli, A; Maris, M; Martin, P G; Martínez-González, E; Masi, S; Matarrese, S; Melchiorri, A; Mendes, L; Mennella, A; Migliaccio, M; Miville-Deschênes, M -A; Moneti, A; Montier, L; Morgante, G; Mortlock, D; Munshi, D; Murphy, J A; Naselsky, P; Nati, F; Netterfield, C B; Noviello, F; Novikov, D; Novikov, I; Oppermann, N; Oxborrow, C A; Pagano, L; Pajot, F; Paladini, R; Paoletti, D; Pasian, F; Perotto, L; Pettorino, V; Piacentini, F; Piat, M; Pierpaoli, E; Pietrobon, D; Plaszczynski, S; Pointecouteau, E; Polenta, G; Ponthieu, N; Pratt, G W; Prunet, S; Puget, J -L; Rachen, J P; Reinecke, M; Remazeilles, M; Renault, C; Renzi, A; Ristorcelli, I; Rocha, G; Rossetti, M; Roudier, G; Rubiño-Martín, J A; Rusholme, B; Sandri, M; Santos, D; Savelainen, M; Savini, G; Scott, D; Soler, J D; Stolyarov, V; Sudiwala, R; Sutton, D; Suur-Uski, A -S; Sygnet, J -F; Tauber, J A; Terenzi, L; Toffolatti, L; Tomasi, M; Tristram, M; Tucci, M; Umana, G; Valenziano, L; Valiviita, J; Van Tent, B; Vielva, P; Villa, F; Wade, L A; Wandelt, B D; Wehus, I K; Ysard, N; Yvon, D; Zonca, A

    2015-01-01T23:59:59.000Z

    Within ten nearby (d < 450 pc) Gould Belt molecular clouds we evaluate statistically the relative orientation between the magnetic field projected on the plane of sky, inferred from the polarized thermal emission of Galactic dust observed by Planck at 353 GHz, and the gas column density structures, quantified by the gradient of the column density, $N_H$. The relative orientation is evaluated pixel by pixel and analyzed in bins of column density using the novel statistical tool Histogram of Relative Orientations. Within most clouds we find that the relative orientation changes progressively with increasing $N_H$ from preferentially parallel or no preferred orientation to preferentially perpendicular. In simulations of magnetohydrodynamic turbulence in molecular clouds this trend in relative orientation is a signature of Alfv\\'enic or sub-Alfv\\'enic turbulence, implying that the magnetic field is significant for the gas dynamics at the scales probed by Planck. We compare the deduced magnetic field strength w...

  1. Ribosomal Database Project II

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    The Ribosomal Database Project (RDP) provides ribosome related data and services to the scientific community, including online data analysis and aligned and annotated Bacterial small-subunit 16S rRNA sequences. As of March 2008, RDP Release 10 is available and currently (August 2009) contains 1,074,075 aligned 16S rRNA sequences. Data that can be downloaded include zipped GenBank and FASTA alignment files, a histogram (in Excel) of the number of RDP sequences spanning each base position, data in the Functional Gene Pipeline Repository, and various user submitted data. The RDP-II website also provides numerous analysis tools.[From the RDP-II home page at http://rdp.cme.msu.edu/index.jsp

  2. Ensemble annealing of complex physical systems

    E-Print Network [OSTI]

    Habeck, Michael

    2015-01-01T23:59:59.000Z

    Algorithms for simulating complex physical systems or solving difficult optimization problems often resort to an annealing process. Rather than simulating the system at the temperature of interest, an annealing algorithm starts at a temperature that is high enough to ensure ergodicity and gradually decreases it until the destination temperature is reached. This idea is used in popular algorithms such as parallel tempering and simulated annealing. A general problem with annealing methods is that they require a temperature schedule. Choosing well-balanced temperature schedules can be tedious and time-consuming. Imbalanced schedules can have a negative impact on the convergence, runtime and success of annealing algorithms. This article outlines a unifying framework, ensemble annealing, that combines ideas from simulated annealing, histogram reweighting and nested sampling with concepts in thermodynamic control. Ensemble annealing simultaneously simulates a physical system and estimates its density of states. The...

  3. Origin of mechanical modifications in poly (ether ether ketone)/carbon nanotube composite

    SciTech Connect (OSTI)

    Pavlenko, Ekaterina; Puech, Pascal; Bacsa, Wolfgang, E-mail: wolfgang.bacsa@cemes.fr [CEMES-CNRS and University of Toulouse, 29 Jeanne Marvig, 31055 Toulouse (France); Boyer, François; Olivier, Philippe [Université de Toulouse, Institut Clément Ader, I.U.T. Université Paul Sabatier - 133C Avenue de Rangueil - B.P. 67701, 31077 Toulouse CEDEX 4 (France); Sapelkin, Andrei [School of Physics and Astronomy, Queen Mary, University of London, Mile End Road, E1 4NS London (United Kingdom); King, Stephen; Heenan, Richard [ISIS Facility, Rutherford Appleton Laboratory, Chilton, OX11 0QX Didcot (United Kingdom); Pons, François; Gauthier, Bénédicte; Cadaux, Pierre-Henri [AIRBUS FRANCE (B.E. M and P Toulouse), 316 Route de Bayonne, 31060 Toulouse (France)

    2014-06-21T23:59:59.000Z

    Variations in the hardness of a poly (ether ether ketone) beam electrically modified with multi-walled carbon nanotubes (MWCNT, 0.5%-3%) are investigated. It is shown that both rupture and hardness variations correlate with the changes in carbon nanotube concentration when using micro indentation and extended Raman imaging. Statistical analysis of the relative spectral intensities in the Raman image is used to estimate local tube concentration and polymer crystallinity. We show that the histogram of the Raman D band across the image provides information about the amount of MWCNTs and the dispersion of MWCNTs in the composite. We speculate that we have observed a local modification of the ordering between pure and modified polymer. This is partially supported by small angle neutron scattering measurements, which indicate that the agglomeration state of the MWCNTs is the same at the concentrations studied.

  4. Sky coverage of orbital detectors. Analytical approach

    E-Print Network [OSTI]

    Diego Casadei

    2005-12-28T23:59:59.000Z

    Orbital detectors without pointing capability have to keep their field of view axis laying on their orbital plane, to observe the largest sky fraction. A general approach to estimate the exposure of each sky element for such detectors is a valuable tool in the R&D phase of a project, when the detector characteristics are still to be fixed. An analytical method to estimate the sky exposure is developed, which makes only few very reasonable approximations. The formulae obtained with this method are used to compute the histogram of the sky exposure of a hypothetical gamma-ray detector installed on the ISS. The C++ code used in this example is freely available on the http://cern.ch/casadei/software.html web page.

  5. Dark counts of superconducting nanowire single-photon detector under illumination

    E-Print Network [OSTI]

    Chen, Sijing; Zhang, Weijun; Yang, Xiaoyan; Li, Hao; Zhang, Lu; Wang, Zhen; Xie, Xiaoming

    2015-01-01T23:59:59.000Z

    An abnormal increase in the SDE was observed for superconducting nanowire single-photon detectors (SNSPDs) when the bias current (Ib) was close to the switching current (Isw). By introducing the time-correlated single-photon counting technique, we investigated the temporal histogram of the detection counts of an SNSPD under illumination. The temporal information helps us to distinguish photon counts from dark counts in the time domain. In this manner, the dark count rate (DCR) under illumination and the accurate SDE can be determined. The DCR under moderate illumination may be significantly larger than the conventional DCR measured without illumination under a high Ib, which causes the abnormal increase in the SDE. The increased DCR may be explained by the suppression of Isw under illumination.

  6. Statistical techniques applied to aerial radiometric surveys (STAARS): principal components analysis user's manual. [NURE program

    SciTech Connect (OSTI)

    Koch, C.D.; Pirkle, F.L.; Schmidt, J.S.

    1981-01-01T23:59:59.000Z

    A Principal Components Analysis (PCA) has been written to aid in the interpretation of multivariate aerial radiometric data collected by the US Department of Energy (DOE) under the National Uranium Resource Evaluation (NURE) program. The variations exhibited by these data have been reduced and classified into a number of linear combinations by using the PCA program. The PCA program then generates histograms and outlier maps of the individual variates. Black and white plots can be made on a Calcomp plotter by the application of follow-up programs. All programs referred to in this guide were written for a DEC-10. From this analysis a geologist may begin to interpret the data structure. Insight into geological processes underlying the data may be obtained.

  7. Study of interdomain boundary in diamagnetic domain structure in beryllium

    E-Print Network [OSTI]

    Philip Lykov

    2002-11-21T23:59:59.000Z

    At low temperatures, in strong magnetic fields, the formation of a non-uniform magnetisation is possible in a single-crystal metal sample whose demagnetising factor along the field is close to unity. Namely, so-called Condon diamagnetic domain structure arises and disappears periodically with magnetic field. In this paper, the diamagnetic domain structure in beryllium single crystalis analysed. Directly, existence of diamagnetic domains in that sample was observed earlier by the muon spin precession (mSR) resonance peak splitting. A method is described that allows to calculate quantitative characteristics of the interdomain boundary using the muon histograms. The technique is based on the Marquardt minimisation procedure that has been modified in order to reduce the influence of noise on iterations convergence. Boundary volume fraction was calculated.

  8. Assessment of the basic energy sciences program. Volume II. Appendices

    SciTech Connect (OSTI)

    Not Available

    1982-03-01T23:59:59.000Z

    A list of experts reviewing the Basic Energy Sciences (BES) program and their organizations are given. The assessment plan is explained; the program examined the following: quality of science being conducted in the program, quality of performers supported by the Basic Energy Sciences (BES) program, and the impact of the research on mission oriented needs. The intent of the assessment is to provide an indication of general status relative to these questions for the BES divisions. The approach to the assessment is described. The sampling plan which was used as a guide in determining the sample size and selecting the sample to evaluate the research program of the Office of Basic Energy Sciences are discussed. Special analyses were conducted on the dispersion of reviewers' ratings, the ratings of the lower funded projects, and the amount of time the principal investigator devoted to the project. These are presented in the final appendix together with histograms for individual rating variables for each program area. (MCW)

  9. Spectral resolution for a five-element, filtered, x-ray detector array using the method of Backus and Gilbert

    SciTech Connect (OSTI)

    Fehl, D. L. [Sandia National Laboratories, Albuquerque, New Mexico 87185-1196 (United States)] [Sandia National Laboratories, Albuquerque, New Mexico 87185-1196 (United States); Biggs, F. [Sandia National Laboratories, Albuquerque, New Mexico 87185-1196 (United States)] [Sandia National Laboratories, Albuquerque, New Mexico 87185-1196 (United States); Chandler, G. A. [Sandia National Laboratories, Albuquerque, New Mexico 87185-1196 (United States)] [Sandia National Laboratories, Albuquerque, New Mexico 87185-1196 (United States); Stygar, W. A. [Sandia National Laboratories, Albuquerque, New Mexico 87185-1196 (United States)] [Sandia National Laboratories, Albuquerque, New Mexico 87185-1196 (United States)

    2000-08-01T23:59:59.000Z

    The generalized method of Backus and Gilbert (BG) is described and applied to the inverse problem of obtaining the spectrum from a five-channel, filtered array of x-ray detectors. This diagnostic is routinely fielded on the Z facility at Sandia National Laboratories to study soft x-ray photons ({approx}100-2300 eV), emitted by high density Z-pinch plasmas. The BG method defines spectral resolution limits on the system of response functions that are in good agreement with a classical unfold method, based on a histogram representation of the source spectrum. The resolution so defined is independent of the source spectrum. For noise-free, simulated data the BG approximating function is also in reasonable agreement with the source spectrum (150 eV blackbody) and the unfolded spectrum. This function may be used as an initial trial function for iterative methods or a regularization model.(c) 2000 American Institute of Physics. (c)

  10. Vector Boson Production at Hadron Colliders: A Fully Exclusive QCD Calculation at Next-to-Next-to-Leading Order

    SciTech Connect (OSTI)

    Catani, Stefano; Ferrera, Giancarlo; Grazzini, Massimiliano [INFN, Sezione di Firenze and Dipartimento di Fisica, Universita di Firenze, I-50019 Sesto Fiorentino, Florence (Italy); Cieri, Leandro; Florian, Daniel de [Departamento de Fisica, FCEYN, Universidad de Buenos Aires, (1428) Pabellon 1 Ciudad Universitaria, Capital Federal (Argentina)

    2009-08-21T23:59:59.000Z

    We consider QCD radiative corrections to the production of W and Z bosons in hadron collisions. We present a fully exclusive calculation up to next-to-next-to-leading order (NNLO) in QCD perturbation theory. To perform this NNLO computation, we use a recently proposed version of the subtraction formalism. The calculation includes the gamma-Z interference, finite-width effects, the leptonic decay of the vector bosons, and the corresponding spin correlations. Our calculation is implemented in a parton level Monte Carlo program. The program allows the user to apply arbitrary kinematical cuts on the final-state leptons and the associated jet activity and to compute the corresponding distributions in the form of bin histograms. We show selected numerical results at the Fermilab Tevatron and the LHC.

  11. Measurement of the ratio [B(D(0)?K*(?)e(+)?e)] / [B(D(0)?K(?)e(+)?e)

    E-Print Network [OSTI]

    Baringer, Philip S.

    1991-12-01T23:59:59.000Z

    as a muon increases from 0.8%%uo at 1.4 GeV/c to 1.4%%uo at 2.0 GeV, and stays constant beyond. III. DETECTION OF D ~K e+v, D 's are required to be decay products of D*+'s from the reaction D*+~D m+. D*+ candidates are formed from three... and transverse polarizations [14]. We have checked our background estimates by using M(Ksvr )(Gev) FIG. 2. The histogram is the Kzm candidate mass for the decay mode D ~K* e+v, . The solid line is a fit to the data using a Breit-Wigner line shape for the signal...

  12. First passage times in integrate-and-fire neurons with stochastic thresholds

    E-Print Network [OSTI]

    Braun, Wilhelm; Thul, Rüdiger

    2015-01-01T23:59:59.000Z

    We consider a leaky integrate--and--fire neuron with deterministic subthreshold dynamics and a firing threshold that evolves as an Ornstein-Uhlenbeck process. The formulation of this minimal model is motivated by the experimentally observed widespread variation of neural firing thresholds. We show numerically that the mean first passage time can depend non-monotonically on the noise amplitude. For sufficiently large values of the correlation time of the stochastic threshold the mean first passage time is maximal for non-vanishing noise. We provide an explanation for this effect by analytically transforming the original model into a first passage time problem for Brownian motion. This transformation also allows for a perturbative calculation of the first passage time histograms. In turn this provides quantitative insights into the mechanisms that lead to the non-monotonic behaviour of the mean first passage time. The perturbation expansion is in excellent agreement with direct numerical simulations. The approa...

  13. Apple Strength Issues

    SciTech Connect (OSTI)

    Syn, C

    2009-12-22T23:59:59.000Z

    Strength of the apple parts has been noticed to decrease, especially those installed by the new induction heating system since the LEP campaign started. Fig. 1 shows the ultimate tensile strength (UTS), yield strength (YS), and elongation of the installed or installation-simulated apples on various systems. One can clearly see the mean values of UTS and YS of the post-LEP parts decreased by about 8 ksi and 6 ksi respectively from those of the pre-LEP parts. The slight increase in elongation seen in Fig.1 can be understood from the weak inverse relationship between the strength and elongation in metals. Fig.2 shows the weak correlation between the YS and elongation of the parts listed in Fig. 1. Strength data listed in Figure 1 were re-plotted as histograms in Figs. 3 and 4. Figs. 3a and 4a show histograms of all UTS and YS data. Figs. 3b and 4b shows histograms of pre-LEP data and Figs. 3c and 4c of post-LEP data. Data on statistical scatter of tensile strengths have been rarely published by material suppliers. Instead, only the minimum 'guaranteed' strength data are typically presented. An example of strength distribution of aluminum 7075-T6 sheet material, listed in Fig. 5, show that its scatter width of both UTS and YS for a single sheet can be about 6 ksi and for multi-lot scatter can be as large as 11 ksi even though the sheets have been produced through well-controlled manufacturing process. By approximating the histograms shown in Figs. 3 and 4 by a Gaussian or similar type of distribution curves, one can plausibly see the strength reductions in the later or more recent apples. The pre-LEP data in Figs. 3b and 4b show wider scatter than the post-LEP data in Figs. 3c and 4c and seem to follow the binomial distribution of strength indicating that the apples might have been made from two different lots of material, either from two different vendors or from two different melts of perhaps slightly different chemical composition by a single vendor. The post-LEP apples seem to have been from a single batch of material. The pre-LEP apples of the weak strength and the post-LEP apples with even weaker strength could have been made of the same batch of material, and the small strength differential might be due to the difference in the induction heating system. If the pre-LEP apples with the lower strength and the post LEP apples are made from the same batch of material, their combined scatter of strength data would be wider and can be understood as a result of the additional processing steps of stress relief and induction heating as discussed.

  14. Computational analysis of kidney scintigrams

    SciTech Connect (OSTI)

    Vrincianu, D.; Puscasu, E.; Creanga, D. [University Al. I. Cuza, Faculty of Physics, 11 Blvd. Carol I, 700506, Iasi (Romania); Stefanescu, C. [University of Medicine and Pharmacy Gr. T. Popa, Iasi (Romania)

    2013-11-13T23:59:59.000Z

    The scintigraphic investigation of normal and pathological kidneys was carried out using specialized gamma-camera device from nuclear medicine hospital department. Technetium 90m isotope with gamma radiation emission, coupled with vector molecules for kidney tissues was introduced into the subject body, its dynamics being recorded as data source for kidney clearance capacity. Two representative data series were investigated, corresponding to healthy and pathological organs respectively. The semi-quantitative tests applied for the comparison of the two distinct medical situations were: the shape of probability distribution histogram, the power spectrum, the auto-correlation function and the Lyapunov exponent. While power spectrum led to similar results in both cases, significant differences were revealed by means of distribution probability, Lyapunov exponent and correlation time, recommending these numerical tests as possible complementary tools in clinical diagnosis.

  15. Multipoint reweighting method and beta functions for the calculation of QCD equation of state

    E-Print Network [OSTI]

    Ryo Iwami; S. Ejiri; K. Kanaya; Y. Nakagawa; T. Umeda; D. Yamamoto

    2015-01-26T23:59:59.000Z

    We study a reweighting method aiming at numerical studies of QCD at finite density, in which the conventional Monte-Carlo method cannot be applied directly. One of the most important problems in the reweighting method is the overlap problem. To solve it, we propose to perform simulations at several simulation points and combine their results in the data analyses. In this report, we introduce this multipoint reweighting method and test if the method works well by measuring histograms of physical quantities. Using this method, we calculate the meson masses as continuous functions of the gauge coupling beta and the hopping parameters kappa in QCD at zero density. We then determine lines of constant physics in the (beta, kappa) space and evaluate the derivatives of the lattice spacing with respect to beta and kappa along the lines of constant physics (inverse of the beta functions), which are needed in a calculation of the equation of state.

  16. Separation of particles leading to decay and unlimited growth of energy in a driven stadium-like billiard

    E-Print Network [OSTI]

    André L. P. Livorati; Matheus S. Palmero; Carl P. Dettmann; Iberê L. Caldas; Edson D. Leonel

    2015-07-01T23:59:59.000Z

    A competition between decay and growth of energy in a time-dependent stadium billiard is discussed giving emphasis in the decay of energy mechanism. A critical resonance velocity is identified for causing of separation between ensembles of high and low energy and a statistical investigation is made using ensembles of initial conditions both above and below the resonance velocity. For high initial velocity, Fermi acceleration is inherent in the system. However for low initial velocity, the resonance allies with stickiness hold the particles in a regular or quasi-regular regime near the fixed points, preventing them from exhibiting Fermi acceleration. Also, a transport analysis along the velocity axis is discussed to quantify the competition of growth and decay of energy and making use distributions of histograms of frequency, and we set that the causes of the decay of energy are due to the capture of the orbits by the resonant fixed points.

  17. Multicriteria optimization of the spatial dose distribution

    SciTech Connect (OSTI)

    Schlaefer, Alexander [Medical Robotics Group, Universität zu Lübeck, Lübeck 23562, Germany and Institute of Medical Technology, Hamburg University of Technology, Hamburg 21073 (Germany)] [Medical Robotics Group, Universität zu Lübeck, Lübeck 23562, Germany and Institute of Medical Technology, Hamburg University of Technology, Hamburg 21073 (Germany); Viulet, Tiberiu [Medical Robotics Group, Universität zu Lübeck, Lübeck 23562 (Germany)] [Medical Robotics Group, Universität zu Lübeck, Lübeck 23562 (Germany); Muacevic, Alexander; Fürweger, Christoph [European CyberKnife Center Munich, Munich 81377 (Germany)] [European CyberKnife Center Munich, Munich 81377 (Germany)

    2013-12-15T23:59:59.000Z

    Purpose: Treatment planning for radiation therapy involves trade-offs with respect to different clinical goals. Typically, the dose distribution is evaluated based on few statistics and dose–volume histograms. Particularly for stereotactic treatments, the spatial dose distribution represents further criteria, e.g., when considering the gradient between subregions of volumes of interest. The authors have studied how to consider the spatial dose distribution using a multicriteria optimization approach.Methods: The authors have extended a stepwise multicriteria optimization approach to include criteria with respect to the local dose distribution. Based on a three-dimensional visualization of the dose the authors use a software tool allowing interaction with the dose distribution to map objectives with respect to its shape to a constrained optimization problem. Similarly, conflicting criteria are highlighted and the planner decides if and where to relax the shape of the dose distribution.Results: To demonstrate the potential of spatial multicriteria optimization, the tool was applied to a prostate and meningioma case. For the prostate case, local sparing of the rectal wall and shaping of a boost volume are achieved through local relaxations and while maintaining the remaining dose distribution. For the meningioma, target coverage is improved by compromising low dose conformality toward noncritical structures. A comparison of dose–volume histograms illustrates the importance of spatial information for achieving the trade-offs.Conclusions: The results show that it is possible to consider the location of conflicting criteria during treatment planning. Particularly, it is possible to conserve already achieved goals with respect to the dose distribution, to visualize potential trade-offs, and to relax constraints locally. Hence, the proposed approach facilitates a systematic exploration of the optimal shape of the dose distribution.

  18. Intensity-modulated radiation therapy (IMRT) dosimetry of the head and neck: A comparison of treatment plans using linear accelerator-based IMRT and helical tomotherapy

    SciTech Connect (OSTI)

    Sheng Ke [Department of Radiation Oncology, University of Virginia, Charlottesville, VA (United States)]. E-mail: ks2mc@virginia.edu; Molloy, Janelle A. [Department of Radiation Oncology, University of Virginia, Charlottesville, VA (United States); Department of Radiation Oncology, Mayo Clinic, Rochester, MN (United States); Read, Paul W. [Department of Radiation Oncology, University of Virginia, Charlottesville, VA (United States)

    2006-07-01T23:59:59.000Z

    Purpose: To date, most intensity-modulated radiation therapy (IMRT) delivery has occurred using linear accelerators (linacs), although helical tomotherapy has become commercially available. To quantify the dosimetric difference, we compared linac-based and helical tomotherapy-based treatment plans for IMRT of the oropharynx. Methods and Materials: We compared the dosimetry findings of 10 patients who had oropharyngeal carcinoma. Five patients each had cancers in the base of the tongue and tonsil. Each plan was independently optimized using either the CORVUS planning system (Nomos Corporation, Sewickly, PA), commissioned for a Varian 2300 CD linear accelerator (Varian Medical Systems, Palo Alto, CA) with 1-cm multileaf collimator leaves, or helical tomotherapy. The resulting treatment plans were evaluated by comparing the dose-volume histograms, equivalent uniform dose (EUD), dose uniformity, and normal tissue complication probabilities. Results: Helical tomotherapy plans showed improvement of critical structure avoidance and target dose uniformity for all patients. The average equivalent uniform dose reduction for organs at risk (OARs) surrounding the base of tongue and the tonsil were 17.4% and 27.14% respectively. An 80% reduction in normal tissue complication probabilities for the parotid glands was observed in the tomotherapy plans relative to the linac-based plans. The standard deviation of the planning target volume dose was reduced by 71%. In our clinic, we use the combined dose-volume histograms for each class of plans as a reference goal for helical tomotherapy treatment planning optimization. Conclusions: Helical tomotherapy provides improved dose homogeneity and normal structure dose compared with linac-based IMRT in the treatment of oropharyngeal carcinoma resulting in a reduced risk for complications from focal hotspots within the planning target volume and for the adjacent parotid glands.

  19. Statistical Assessment of Proton Treatment Plans Under Setup and Range Uncertainties

    SciTech Connect (OSTI)

    Park, Peter C.; Cheung, Joey P.; Zhu, X. Ronald [Department of Radiation Physics, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Lee, Andrew K. [Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Sahoo, Narayan [Department of Radiation Physics, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Tucker, Susan L. [Department of Bioinformatics and Computational Biology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Liu, Wei; Li, Heng; Mohan, Radhe; Court, Laurence E. [Department of Radiation Physics, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Dong, Lei, E-mail: dong.lei@scrippshealth.org [Scripps Proton Therapy Center, San Diego, California (United States)

    2013-08-01T23:59:59.000Z

    Purpose: To evaluate a method for quantifying the effect of setup errors and range uncertainties on dose distribution and dose–volume histogram using statistical parameters; and to assess existing planning practice in selected treatment sites under setup and range uncertainties. Methods and Materials: Twenty passively scattered proton lung cancer plans, 10 prostate, and 1 brain cancer scanning-beam proton plan(s) were analyzed. To account for the dose under uncertainties, we performed a comprehensive simulation in which the dose was recalculated 600 times per given plan under the influence of random and systematic setup errors and proton range errors. On the basis of simulation results, we determined the probability of dose variations and calculated the expected values and standard deviations of dose–volume histograms. The uncertainties in dose were spatially visualized on the planning CT as a probability map of failure to target coverage or overdose of critical structures. Results: The expected value of target coverage under the uncertainties was consistently lower than that of the nominal value determined from the clinical target volume coverage without setup error or range uncertainty, with a mean difference of ?1.1% (?0.9% for breath-hold), ?0.3%, and ?2.2% for lung, prostate, and a brain cases, respectively. The organs with most sensitive dose under uncertainties were esophagus and spinal cord for lung, rectum for prostate, and brain stem for brain cancer. Conclusions: A clinically feasible robustness plan analysis tool based on direct dose calculation and statistical simulation has been developed. Both the expectation value and standard deviation are useful to evaluate the impact of uncertainties. The existing proton beam planning method used in this institution seems to be adequate in terms of target coverage. However, structures that are small in volume or located near the target area showed greater sensitivity to uncertainties.

  20. Retrospective review of Contura HDR breast cases to improve our standardized procedure

    SciTech Connect (OSTI)

    Iftimia, Ileana, E-mail: Ileana.n.iftimia@lahey.org [Lahey Clinic, Radiation Oncology Department, MA (United States); Cirino, Eileen T.; Ladd, Ron; Mower, Herbert W.; McKee, Andrea B. [Lahey Clinic, Radiation Oncology Department, MA (United States)

    2013-07-01T23:59:59.000Z

    To retrospectively review our first 20 Contura high dose rate breast cases to improve and refine our standardized procedure and checklists. We prepared in advance checklists for all steps, developed an in-house Excel spreadsheet for second checking the plan, and generated a procedure for efficient contouring and a set of optimization constraints to meet the dose volume histogram criteria. Templates were created in our treatment planning system for structures, isodose levels, optimization constraints, and plan report. This study reviews our first 20 high dose rate Contura breast treatment plans. We followed our standardized procedure for contouring, planning, and second checking. The established dose volume histogram criteria were successfully met for all plans. For the cases studied here, the balloon-skin and balloon-ribs distances ranged between 5 and 43 mm and 1 and 33 mm, respectively; air{sub s}eroma volume/PTV{sub E}val volume?5.5% (allowed?10%); asymmetry<1.2 mm (goal?2 mm); PTV{sub E}val V90%?97.6%; PTV{sub E}val V95%?94.9%; skin max dose?98%Rx; ribs max dose?137%Rx; V150%?29.8 cc; V200%?7.8 cc; the total dwell time range was 225.4 to 401.9 seconds; and the second check agreement was within 3%. Based on this analysis, more appropriate ranges for the total dwell time and balloon diameter tolerance were found. Three major problems were encountered: balloon migration toward the skin for small balloon-to-skin distances, lumen obstruction, and length change for the flexible balloon. Solutions were found for these issues and our standardized procedure and checklists were updated accordingly. Based on our review of these cases, the use of checklists resulted in consistent results, indicating good coverage for the target without sacrificing the critical structures. This review helped us to refine our standardized procedure and update our checklists.

  1. NON-THERMAL RESPONSE OF THE CORONA TO THE MAGNETIC FLUX DISPERSAL IN THE PHOTOSPHERE OF A DECAYING ACTIVE REGION

    SciTech Connect (OSTI)

    Harra, L. K. [UCL-Mullard Space Science Laboratory, Holmbury St. Mary, Dorking, Surrey, RH5 6NT (United Kingdom); Abramenko, V. I. [Big Bear Solar Observatory, 40386 N. Shore Lane, Big Bear City, CA 92314 (United States)

    2012-11-10T23:59:59.000Z

    We analyzed Solar Dynamics Observatory line-of-sight magnetograms for a decaying NOAA active region (AR) 11451 along with co-temporal Extreme-Ultraviolet Imaging Spectrometer (EIS) data from the Hinode spacecraft. The photosphere was studied via time variations of the turbulent magnetic diffusivity coefficient, {eta}(t), and the magnetic power spectrum index, {alpha}, through analysis of magnetogram data from the Helioseismic and Magnetic Imager (HMI). These measure the intensity of the random motions of magnetic elements and the state of turbulence of the magnetic field, respectively. The time changes of the non-thermal energy release in the corona was explored via histogram analysis of the non-thermal velocity, v {sub nt}, in order to highlight the largest values at each time, which may indicate an increase in energy release in the corona. We used the 10% upper range of the histogram of v {sub nt} (which we called V {sup upp} {sub nt}) of the coronal spectral line of Fe XII 195 A. A 2 day time interval was analyzed from HMI data, along with the EIS data for the same field of view. Our main findings are the following. (1) The magnetic turbulent diffusion coefficient, {eta}(t), precedes the upper range of the v {sub nt} with the time lag of approximately 2 hr and the cross-correlation coefficient of 0.76. (2) The power-law index, {alpha}, of the magnetic power spectrum precedes V {sup upp} {sub nt} with a time lag of approximately 3 hr and the cross-correlation coefficient of 0.5. The data show that the magnetic flux dispersal in the photosphere is relevant to non-thermal energy release dynamics in the above corona. The results are consistent with the nanoflare mechanism of the coronal heating, due to the time lags being consistent with the process of heating and cooling the loops heated by nanoflares.

  2. TFE verification program

    SciTech Connect (OSTI)

    Not Available

    1991-04-01T23:59:59.000Z

    The program objective is to demonstrate the technology readiness of a thermionic fuel element (TFE) suitable for use as the basic element in a thermionic reactor with electric power output in the 0.5 to 5.0 MW(e) range, and a full-power life of 7 years. This report states progress made in the following tasks: concept design, converter performance, insulator seal, sheath insulator, fueled emitter, cesium reservoir and interconnective TFE components, and thermionic fuel element testing. 20 refs., 39 refs., 32 figs. (GHH)

  3. An Investigation of Using Isochoric Data Points in the Development of Natural Gas Equation of State

    E-Print Network [OSTI]

    Khazndar, Aoubai M

    2014-02-27T23:59:59.000Z

    gas consumer and will account for 55 percent of total gas use in 2035. This increase of natural gas consumption can be attributed to the big LNG and GTL projects that exist in this region. Qatar more than doubled its LNG liquefaction capacity over... the last 7-years and more than doubled its fuel use in LNG liquefaction plants. [18, 19] In addition to the two GTL facilities (Oryx and Pearl) that are located in Qatar. The Oryx plant consumes 120 billion cubic feet of natural gas per year and produces...

  4. Low-mass evolution from HE ignition to beyond the horizontal branch

    SciTech Connect (OSTI)

    Despain, K.

    1980-01-01T23:59:59.000Z

    The evolution of an 0.6 M/sub solar mass/ stellar model during core helium burning is presented. Following the off-center ignition of helium in the core flash, the star remains on the red giant branch for > 10/sup 6/ years, undergoing twelve additional flashes. After leaving the giant branch, the star evolves on the horizontal branch for 8.15 x 10/sup 7/ years before returning to the giant branch and undergoing strong helium-shell flashes. The implications for horizontal branch and RR Lyrae stars are discussed.

  5. Angular momentum extraction by gravity waves in the Sun

    E-Print Network [OSTI]

    Suzanne Talon; Pawan Kumar; Jean-Paul Zahn

    2002-06-27T23:59:59.000Z

    We review the behavior of the oscillating shear layer produced by gravity waves below the surface convection zone of the Sun. We show that, under asymmetric filtering produced by this layer, gravity waves of low spherical order, which are stochastically excited at the base of the convection zone of late type stars, can extract angular momentum from their radiative interior. The time-scale for this momentum extraction in a Sun-like star is of the order of 10^7 years. The process is particularly efficient in the central region, and it could produce there a slowly rotating core.

  6. ON THE LINEAR TERM CORRECTION FOR NEEDLET/WAVELET NON-GAUSSIANITY ESTIMATORS

    SciTech Connect (OSTI)

    Donzelli, Simona [INAF-Istituto di Astrofisica Spaziale e Fisica Cosmica Milano, Via E. Bassini 15, 20133 Milano (Italy); Hansen, Frode K. [Institute of Theoretical Astrophysics, University of Oslo, P.O. Box 1029 Blindern, N-0315 Oslo (Norway); Liguori, Michele; Matarrese, Sabino [Dipartimento di Fisica e Astronomia 'G. Galilei', Universita di Padova, Universita degli Studi di Padova, Via Marzolo 8, 35131 Padova (Italy); Marinucci, Domenico, E-mail: donzelli@iasf-milano.inaf.it [Dipartimento di Matematica, Universita di Roma 'Tor Vergata', Via della Ricerca Scientifica 1, I-00133 Roma (Italy)

    2012-08-10T23:59:59.000Z

    We derive the linear correction term for needlet and wavelet estimators of the bispectrum and the nonlinearity parameter f{sub NL} on cosmic microwave background radiation data. We show that on masked WMAP-like data with anisotropic noise, the error bars improve by 10%-20% and almost reach the optimal error bars obtained with the bispectrum estimator also known as 'KSW'. In the limit of full-sky and isotropic noise, this term vanishes. We apply needlet and wavelet estimators to the WMAP 7-year data and obtain our best estimate f{sub NL} = 37.5 {+-} 21.8 (68% CL).

  7. Improvement of tap holes at Wakayama No. 5 blast furnace

    SciTech Connect (OSTI)

    Yamashita, M.; Kashiwada, M.; Shibuta, H. [Sumitomo Metal Industries, Ltd., Wakayama (Japan). Wakayama Steel Works

    1995-12-01T23:59:59.000Z

    The service life of blast furnaces, as the result of various improvement measures, has been extended from the conventional 5 to 7 years to 15 to 20 years. Wakayama No. 5 blast furnace adopted SiC bricks. Though SiC brick excelled in strength and durability, it has raised problems such as tap hole inside temperature lowering attributable to its high thermal conductivity, insufficient mud burning and gas blow-out. Nevertheless, various countermeasures described within have been taken against such problems, and as the result it has now become possible to maintain tap holes in stable conditions.

  8. Blastoid studies

    E-Print Network [OSTI]

    Fay, R. O.

    1961-10-30T23:59:59.000Z

    and taxonomy of these fossils. In 1886, R. ETHERIDGE & P. H. CARPENTER published a compre- hensive study of the blastoids, similar to but much more exhaustive than the earlier work by ROEMER. Their paper, based on 7 years of intensive study of 6 THE UNIVERSITY... published on some Devonian and Mississippian blastoids of North America. Since then, little has been added to our knowledge except details of strati- graphic occurrence, as in the papers by K. JOYSEY (1953-1959). In 1943, R. S. BASSLER & M. W. MOODEY...

  9. A generalized land use study of the San Jacinto River watershed of Texas

    E-Print Network [OSTI]

    Buckley, Frank A.

    1951-01-01T23:59:59.000Z

    Pi ? ? ft o ] 00 I to jco jco j ? co 03 ? 5 ^ O aS ?? ?? ?p U Pi ? ? ft O 4? CQ ? U O aS ?? ?* 43 U Pi ? ? ft O BG uo CM n CM c> o 2 0 t - cr... ?P = Q ?* ^ft ? = -p ? c3 ^ O > T i ? n3 *H ? <35 J i JL, DO * CQ CJ -PCO O ciJ o CO ft O 4= P i ? O O o CO ? Q 7-Year Average 1933-1939* Slope...

  10. The path from Hoshin Kanri to True North.

    SciTech Connect (OSTI)

    Galaviz, Maria Esther; McCaughey, Kathleen G.

    2010-08-01T23:59:59.000Z

    This year completed our 5th cycle of Hoshin Kanri. It has provided a way to summarize our annual strategic planning outcome in a simple format,and a great means to communicate it to employees. It has increased everyone's understanding of the Center's vision and true north. Every employee understands how their work contributes to the Center's success. It has increased focus and alignment in the organization and has increased ESat results with regards to improved alighment. It has tripled the number of shipments and increased productivity by 175% in 7 years.

  11. Discovery of Localized Regions of Excess 10-TeV Cosmic Rays

    E-Print Network [OSTI]

    Abdo, A A; Aune, T; Berley, D; Blaufuss, E; Casanova, S; Chen, C; Dingus, B L; Ellsworth, R W; Fleysher, L; Fleysher, R; Gonzales, M M; Goodman, J A; Hoffman, C M; Hüntemeyer, P H; Kolterman, B E; Lansdell, C P; Linnemann, J T; McEnery, J E; Mincer, A I; Némethy, P; Noyes, D; Pretz, J; Ryan, J M; Parkinson, P M Saz; Shoup, A; Sinnis, G; Smith, A J; Sullivan, G W; Vasileiou, V; Walker, G P; Williams, D A; Yodh, G B

    2008-01-01T23:59:59.000Z

    An analysis of 7 years of Milagro data performed on a 10-degree angular scale has found two localized regions of excess of unknown origin with greater than 12 sigma significance. Both regions are inconsistent with gamma-ray emission at a level of 11 sigma. One of the regions has a different energy spectrum than the isotropic cosmic-ray flux at a level of 4.6 sigma, and it is consistent with hard spectrum protons with an exponential cutoff, with the most significant excess at ~10 TeV. Potential causes of these excesses are explored, but no compelling explanations are found.

  12. Discovery of Localized Regions of Excess 10-TeV Cosmic Rays

    E-Print Network [OSTI]

    A. A. Abdo; B. Allen; T. Aune; D. Berley; E. Blaufuss; S. Casanova; C. Chen; B. L. Dingus; R. W. Ellsworth; L. Fleysher; R. Fleysher; M. M. Gonzales; J. A. Goodman; C. M. Hoffman; P. H. Hüntemeyer; B. E. Kolterman; C. P. Lansdell; J. T. Linnemann; J. E. McEnery; A. I. Mincer; P. Nemethy; D. Noyes; J. Pretz; J. M. Ryan; P. M. Saz Parkinson; A. Shoup; G. Sinnis; A. J. Smith; G. W. Sullivan; V. Vasileiou; G. P. Walker; D. A. Williams; G. B. Yodh

    2008-10-14T23:59:59.000Z

    An analysis of 7 years of Milagro data performed on a 10-degree angular scale has found two localized regions of excess of unknown origin with greater than 12 sigma significance. Both regions are inconsistent with gamma-ray emission with high confidence. One of the regions has a different energy spectrum than the isotropic cosmic-ray flux at a level of 4.6 sigma, and it is consistent with hard spectrum protons with an exponential cutoff, with the most significant excess at ~10 TeV. Potential causes of these excesses are explored, but no compelling explanations are found.

  13. Ethylene Market Activity in the 1990s

    E-Print Network [OSTI]

    Field, S.; McCormack, G.

    scenario will not change. OverlY ambitious capacity bUilding which occurred in the late 1970s. combined wIth industrial slagnation In the early 1980s produced overcapacity, miserable pr"ofi ts and the industry shakeout whIch was experienced....e-by""site analYSIS indicate that. ethylene capacity willgro~ b 5-7 %/year. The supply prOjectIon are more predIctable lhan the growth projectIons. If both projections hold UP. price erosion will continue. result~nq in poor t no pr"ofits for' d new plant...

  14. Update of lessons learned from cleanup projects at Oak Ridge

    SciTech Connect (OSTI)

    Sleeman, R.C. [USDOE Oak Ridge Operations, TN (United States)

    1993-12-31T23:59:59.000Z

    The Oak Ridge Operations (ORO) of the US Department of Energy (DOE) has been actively pursuing environmental cleanup of chemically and radioactively contaminated sites for about 7 years. These cleanup projects are carried out under the regulatory requirements of the US Environmental Protection Agency and the various states in which the remedial sites are located. This paper updates and re-examines some of the successes and failures of Oak Ridge cleanup activities, with the intent of encouraging improvements in the areas of safety, project planning, quality assurance, training, and regulatory interactions in future remedial projects.

  15. Demographic analysis of the captive Asian and African elephants in North America

    E-Print Network [OSTI]

    Fraser, Susan Overman

    1983-01-01T23:59:59.000Z

    in Portland, Oregon. In wild populations of African elephants the mean calving interval ranges from 2. 9 to 9. 1 years and breeding ceases after the female reaches about 55 years of age (Laws et al. 1975). Female Asian elephants mature as early as 6 years... years for females and 11. 2 years for males with an overall average of 20. 7 years. Ages range from a 10 month old captive-born male at Portland, Oregon to a 60 year old female at Lafayette, Virginia. The modal age is 12 years and the oldest living...

  16. Massena, NY Natural Gas Pipeline Exports to Canada (Million Cubic Feet)

    Gasoline and Diesel Fuel Update (EIA)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742 33 111 1,613 122 40 Buildingto China (Million Cubic Feet) 3 00.0Feet)Year Jan Feb Marper2.7Year

  17. Oklahoma Dry Natural Gas Production (Million Cubic Feet)

    U.S. Energy Information Administration (EIA) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5 Tables July 1996 Energy Information Administration Office ofthroughYear Jan Feb Mar Apr May Jun Jul9Thousand Cubic Feet)7Year Jan

  18. Oklahoma Dry Natural Gas Proved Reserves

    U.S. Energy Information Administration (EIA) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5 Tables July 1996 Energy Information Administration Office ofthroughYear Jan Feb Mar Apr May Jun Jul9Thousand Cubic Feet)7Year

  19. Wyoming Dry Natural Gas Production (Million Cubic Feet)

    U.S. Energy Information Administration (EIA) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for On-Highway4,1,50022,3,,,,6,1,9,1,50022,3,,,,6,1,Decade Year-0 Year-1 Year-2 Year-3 Year-4 Year-5 Year-6 Year-7 Year-8

  20. Accident sequence precursor events with age-related contributors

    SciTech Connect (OSTI)

    Murphy, G.A.; Kohn, W.E.

    1995-12-31T23:59:59.000Z

    The Accident Sequence Precursor (ASP) Program at ORNL analyzed about 14.000 Licensee Event Reports (LERs) filed by US nuclear power plants 1987--1993. There were 193 events identified as precursors to potential severe core accident sequences. These are reported in G/CR-4674. Volumes 7 through 20. Under the NRC Nuclear Plant Aging Research program, the authors evaluated these events to determine the extent to which component aging played a role. Events were selected that involved age-related equipment degradation that initiated an event or contributed to an event sequence. For the 7-year period, ORNL identified 36 events that involved aging degradation as a contributor to an ASP event. Except for 1992, the percentage of age-related events within the total number of ASP events over the 7-year period ({approximately}19%) appears fairly consistent up to 1991. No correlation between plant ape and number of precursor events was found. A summary list of the age-related events is presented in the report.

  1. Dose impact in radiographic lung injury following lung SBRT: Statistical analysis and geometric interpretation

    SciTech Connect (OSTI)

    Yu, Victoria; Kishan, Amar U.; Cao, Minsong; Low, Daniel; Lee, Percy; Ruan, Dan, E-mail: druan@mednet.ucla.edu [Department of Radiation Oncology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, California 90024 (United States)] [Department of Radiation Oncology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, California 90024 (United States)

    2014-03-15T23:59:59.000Z

    Purpose: To demonstrate a new method of evaluating dose response of treatment-induced lung radiographic injury post-SBRT (stereotactic body radiotherapy) treatment and the discovery of bimodal dose behavior within clinically identified injury volumes. Methods: Follow-up CT scans at 3, 6, and 12 months were acquired from 24 patients treated with SBRT for stage-1 primary lung cancers or oligometastic lesions. Injury regions in these scans were propagated to the planning CT coordinates by performing deformable registration of the follow-ups to the planning CTs. A bimodal behavior was repeatedly observed from the probability distribution for dose values within the deformed injury regions. Based on a mixture-Gaussian assumption, an Expectation-Maximization (EM) algorithm was used to obtain characteristic parameters for such distribution. Geometric analysis was performed to interpret such parameters and infer the critical dose level that is potentially inductive of post-SBRT lung injury. Results: The Gaussian mixture obtained from the EM algorithm closely approximates the empirical dose histogram within the injury volume with good consistency. The average Kullback-Leibler divergence values between the empirical differential dose volume histogram and the EM-obtained Gaussian mixture distribution were calculated to be 0.069, 0.063, and 0.092 for the 3, 6, and 12 month follow-up groups, respectively. The lower Gaussian component was located at approximately 70% prescription dose (35 Gy) for all three follow-up time points. The higher Gaussian component, contributed by the dose received by planning target volume, was located at around 107% of the prescription dose. Geometrical analysis suggests the mean of the lower Gaussian component, located at 35 Gy, as a possible indicator for a critical dose that induces lung injury after SBRT. Conclusions: An innovative and improved method for analyzing the correspondence between lung radiographic injury and SBRT treatment dose has been demonstrated. Bimodal behavior was observed in the dose distribution of lung injury after SBRT. Novel statistical and geometrical analysis has shown that the systematically quantified low-dose peak at approximately 35 Gy, or 70% prescription dose, is a good indication of a critical dose for injury. The determined critical dose of 35 Gy resembles the critical dose volume limit of 30 Gy for ipsilateral bronchus in RTOG 0618 and results from previous studies. The authors seek to further extend this improved analysis method to a larger cohort to better understand the interpatient variation in radiographic lung injury dose response post-SBRT.

  2. Effects of Respiratory Motion on Passively Scattered Proton Therapy Versus Intensity Modulated Photon Therapy for Stage III Lung Cancer: Are Proton Plans More Sensitive to Breathing Motion?

    SciTech Connect (OSTI)

    Matney, Jason; Park, Peter C. [Department of Radiation Physics, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); The University of Texas Graduate School of Biomedical Sciences, Houston, Texas (United States); Bluett, Jaques [Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Chen, Yi Pei [Department of Radiation Physics, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); The University of Texas Graduate School of Biomedical Sciences, Houston, Texas (United States); Liu, Wei; Court, Laurence E. [Department of Radiation Physics, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Liao, Zhongxing [Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Li, Heng [Department of Radiation Physics, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Mohan, Radhe, E-mail: rmohan@mdanderson.org [Department of Radiation Physics, University of Texas MD Anderson Cancer Center, Houston, Texas (United States)

    2013-11-01T23:59:59.000Z

    Purpose: To quantify and compare the effects of respiratory motion on paired passively scattered proton therapy (PSPT) and intensity modulated photon therapy (IMRT) plans; and to establish the relationship between the magnitude of tumor motion and the respiratory-induced dose difference for both modalities. Methods and Materials: In a randomized clinical trial comparing PSPT and IMRT, radiation therapy plans have been designed according to common planning protocols. Four-dimensional (4D) dose was computed for PSPT and IMRT plans for a patient cohort with respiratory motion ranging from 3 to 17 mm. Image registration and dose accumulation were performed using grayscale-based deformable image registration algorithms. The dose–volume histogram (DVH) differences (4D-3D [3D = 3-dimensional]) were compared for PSPT and IMRT. Changes in 4D-3D dose were correlated to the magnitude of tumor respiratory motion. Results: The average 4D-3D dose to 95% of the internal target volume was close to zero, with 19 of 20 patients within 1% of prescribed dose for both modalities. The mean 4D-3D between the 2 modalities was not statistically significant (P<.05) for all dose–volume histogram indices (mean ± SD) except the lung V5 (PSPT: +1.1% ± 0.9%; IMRT: +0.4% ± 1.2%) and maximum cord dose (PSPT: +1.5 ± 2.9 Gy; IMRT: 0.0 ± 0.2 Gy). Changes in 4D-3D dose were correlated to tumor motion for only 2 indices: dose to 95% planning target volume, and heterogeneity index. Conclusions: With our current margin formalisms, target coverage was maintained in the presence of respiratory motion up to 17 mm for both PSPT and IMRT. Only 2 of 11 4D-3D indices (lung V5 and spinal cord maximum) were statistically distinguishable between PSPT and IMRT, contrary to the notion that proton therapy will be more susceptible to respiratory motion. Because of the lack of strong correlations with 4D-3D dose differences in PSPT and IMRT, the extent of tumor motion was not an adequate predictor of potential dosimetric error caused by breathing motion.

  3. Application of the gamma evaluation method in Gamma Knife film dosimetry

    SciTech Connect (OSTI)

    Park, Jeong-Hoon; Han, Jung Ho; Kim, Chae-Yong; Oh, Chang Wan; Lee, Do-Heui; Suh, Tae-Suk; Gyu Kim, Dong; Chung, Hyun-Tai [Department of Neurosurgery, Seoul National University Bundang Hospital, Seongnam 463-707, Korea and Department of Biomedical Engineering, College of Medicine, Catholic University of Korea Seoul 137-701 (Korea, Republic of); Department of Neurosurgery, Seoul National University Bundang Hospital, Seongnam 463-707, Korea and Department of Neurosurgery, College of Medicine, Seoul National University, Seoul 110-799 (Korea, Republic of); Department of Neurosurgery, Asan Medical Center, College of Medicine, University of Ulsan, Seoul 138-736 (Korea, Republic of); Department of Biomedical Engineering and Research Institute of Biomedical Engineering, College of Medicine, Catholic University of Korea, Seoul 137-701 (Korea, Republic of); Department of Neurosurgery, College of Medicine, Seoul National University, Seoul 110-799 (Korea, Republic of)

    2011-10-15T23:59:59.000Z

    Purpose: Gamma Knife (GK) radiosurgery is a minimally invasive surgical technique for the treatment of intracranial lesions. To minimize neurological deficits, submillimeter accuracy is required during treatment delivery. In this paper, the delivery accuracy of GK radiosurgery was assessed with the gamma evaluation method using planning dose distribution and film measurement data. Methods: Single 4, 8, and 16 mm and composite shot plans were developed for evaluation using the GK Perfexion (PFX) treatment planning system (TPS). The planning dose distributions were exported as digital image communications in medicine - radiation therapy (DICOM RT) files using a new function of GK TPS. A maximum dose of 8 Gy was prescribed for four test plans. Irradiation was performed onto a spherical solid water phantom using Gafchromic EBT2 films in the axial and coronal planes. The exposed films were converted to absolute dose based on a 4th-order polynomial calibration curve determined using ten calibration films. The film measurement results and planning dose distributions were registered for further analysis in the same Leksell coordinate using in-house software. The gamma evaluation method was applied to two dose distributions with varying spatial tolerance (0.3-2.0 mm) and dosimetric tolerance (0.3-2.0%), to verify the accuracy of GK radiosurgery. The result of gamma evaluation was assessed using pass rate, dose gamma index histogram (DGH), and dose pass rate histogram (DPH). Results: The 20, 50, and 80% isodose lines found in film measurements were in close agreement with the planning isodose lines, for all dose levels. The comparison of diagonal line profiles across the axial plane yielded similar results. The gamma evaluation method resulted in high pass rates of >95% within the 50% isodose line for 0.5 mm/0.5% tolerance criteria, in both the axial and coronal planes. They satisfied 1.0 mm/1.0% criteria within the 20% isodose line. Our DGH and DPH also showed that low isodose lines exhibited inferior gamma indexes and pass rates compared with higher isodose lines. Conclusions: The gamma evaluation method was applicable to GK radiosurgery. For all test plans, planning dose distribution and film measurement met the tolerance criteria of 0.5 mm/0.5% within the 50% isodose line which are used for marginal dose prescription.

  4. Statistical density modification using local pattern matching

    SciTech Connect (OSTI)

    Terwilliger, Thomas C., E-mail: terwilliger@lanl.gov [Mail Stop M888, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States)

    2003-10-01T23:59:59.000Z

    Statistical density modification can make use of local patterns of density found in protein structures to improve crystallographic phases. A method for improving crystallographic phases is presented that is based on the preferential occurrence of certain local patterns of electron density in macromolecular electron-density maps. The method focuses on the relationship between the value of electron density at a point in the map and the pattern of density surrounding this point. Patterns of density that can be superimposed by rotation about the central point are considered equivalent. Standard templates are created from experimental or model electron-density maps by clustering and averaging local patterns of electron density. The clustering is based on correlation coefficients after rotation to maximize the correlation. Experimental or model maps are also used to create histograms relating the value of electron density at the central point to the correlation coefficient of the density surrounding this point with each member of the set of standard patterns. These histograms are then used to estimate the electron density at each point in a new experimental electron-density map using the pattern of electron density at points surrounding that point and the correlation coefficient of this density to each of the set of standard templates, again after rotation to maximize the correlation. The method is strengthened by excluding any information from the point in question from both the templates and the local pattern of density in the calculation. A function based on the origin of the Patterson function is used to remove information about the electron density at the point in question from nearby electron density. This allows an estimation of the electron density at each point in a map, using only information from other points in the process. The resulting estimates of electron density are shown to have errors that are nearly independent of the errors in the original map using model data and templates calculated at a resolution of 2.6 Å. Owing to this independence of errors, information from the new map can be combined in a simple fashion with information from the original map to create an improved map. An iterative phase-improvement process using this approach and other applications of the image-reconstruction method are described and applied to experimental data at resolutions ranging from 2.4 to 2.8 Å.

  5. Long-term Survival and Toxicity in Patients Treated With High-Dose Intensity Modulated Radiation Therapy for Localized Prostate Cancer

    SciTech Connect (OSTI)

    Spratt, Daniel E.; Pei, Xin; Yamada, Josh; Kollmeier, Marisa A.; Cox, Brett [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States)] [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Zelefsky, Michael J., E-mail: zelefskm@mskcc.org [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States)

    2013-03-01T23:59:59.000Z

    Purpose: To report long-term survival and toxicity outcomes with the use of high-dose intensity modulated radiation therapy (IMRT) to 86.4 Gy for patients with localized prostate cancer. Methods and Materials: Between August 1997 and December 2008, 1002 patients were treated to a dose of 86.4 Gy using a 5-7 field IMRT technique. Patients were stratified by prognostic risk group based on National Comprehensive Cancer Network risk classification criteria. A total of 587 patients (59%) were treated with neoadjuvant and concurrent androgen deprivation therapy. The median follow-up for the entire cohort was 5.5 years (range, 1-14 years). Results: For low-, intermediate-, and high-risk groups, 7-year biochemical relapse-free survival outcomes were 98.8%, 85.6%, and 67.9%, respectively (P<.001), and distant metastasis-free survival rates were 99.4%, 94.1%, and 82.0% (P<.001), respectively. On multivariate analysis, T stage (P<.001), Gleason score (P<.001), and >50% of initial biopsy positive core (P=.001) were predictive for distant mestastases. No prostate cancer-related deaths were observed in the low-risk group. The 7-year prostate cancer-specific mortality (PCSM) rates, using competing risk analysis for intermediate- and high-risk groups, were 3.3% and 8.1%, respectively (P=.008). On multivariate analysis, Gleason score (P=.004), percentage of biopsy core positivity (P=.003), and T-stage (P=.033) were predictive for PCSM. Actuarial 7-year grade 2 or higher late gastrointestinal and genitourinary toxicities were 4.4% and 21.1%, respectively. Late grade 3 gastrointestinal and genitourinary toxicity was experienced by 7 patients (0.7%) and 22 patients (2.2%), respectively. Of the 427 men with full potency at baseline, 317 men (74%) retained sexual function at time of last follow-up. Conclusions: This study represents the largest cohort of patients treated with high-dose radiation to 86.4 Gy, using IMRT for localized prostate cancer, with the longest follow-up to date. Our findings indicate that this treatment results in excellent clinical outcomes with acceptable toxicity.

  6. Separation of particles leading to decay and unlimited growth of energy in a driven stadium-like billiard

    E-Print Network [OSTI]

    André L. P. Livorati; Matheus S. Palmero; Carl P. Dettmann; Iberê L. Caldas; Edson D. Leonel

    2013-12-25T23:59:59.000Z

    A competition between decay and growth of energy in a time-dependent stadium billiard is discussed. The dynamics of an ensemble of non-interacting particles inside a closed domain in the shape of a stadium is described by the use of a four-dimensional non-linear mapping. A critical resonance velocity is identified for causing of separation between ensembles of high and low energy. A statistical investigation is made using ensembles of initial conditions both above and below the resonance velocity. Transport along the velocity axis is discussed to quantify the competition of growth and decay of energy by using distributions of histograms of frequency. For high initial velocity, Fermi acceleration -- unlimited energy growth due collisions of a classical particle to a moving boundary -- is inherent in the system. However for low initial velocity, the resonance allies with stickiness to hold the particles in a regular or quasi-regular regime near the fixed points, preventing them from exhibiting Fermi acceleration.

  7. Analyzing and Visualizing Cosmological Simulations with ParaView

    SciTech Connect (OSTI)

    Woodring, Jonathan [Los Alamos National Laboratory (LANL); Heitmann, Katrin [ORNL; Ahrens, James P [ORNL; Fasel, Patricia [Los Alamos National Laboratory (LANL); Hsu, Chung-Hsing [ORNL; Habib, Salman [ORNL; Pope, Adrian [Los Alamos National Laboratory (LANL)

    2011-01-01T23:59:59.000Z

    The advent of large cosmological sky surveys - ushering in the era of precision cosmology - has been accompanied by ever larger cosmological simulations. The analysis of these simulations, which currently encompass tens of billions of particles and up to a trillion particles in the near future, is often as daunting as carrying out the simulations in the first place. Therefore, the development of very efficient analysis tools combining qualitative and quantitative capabilities is a matter of some urgency. In this paper, we introduce new analysis features implemented within ParaView, a fully parallel, open-source visualization toolkit, to analyze large N-body simulations. A major aspect of ParaView is that it can live and operate on the same machines and utilize the same parallel power as the simulation codes themselves. In addition, data movement is in a serious bottleneck now and will become even more of an issue in the future; an interactive visualization and analysis tool that can handle data in situ is fast becoming essential. The new features in ParaView include particle readers and a very efficient halo finder that identifies friends-of-friends halos and determines common halo properties, including spherical overdensity properties. In combination with many other functionalities already existing within ParaView, such as histogram routines or interfaces to programming languages like Python, this enhanced version enables fast, interactive, and convenient analyses of large cosmological simulations. In addition, development paths are available for future extensions.

  8. The Statistics of the Prompt-to-Afterglow GRB Flux Ratios and the Supercritical Pile GRB Model

    E-Print Network [OSTI]

    Kazanas, D; Sultana, J; Mastichiadis, A

    2015-01-01T23:59:59.000Z

    We present the statistics of the ratio, ${\\mathrm R}$, between the prompt and afterglow "plateau" fluxes of GRB. This we define as the ratio between the mean prompt energy flux in the {\\em Swift} BAT and the {\\em Swift} XRT, immediately following the steep transition between these two states and the beginning of the afterglow stage referred to as the "plateau". Like the distribution of other GRB observables, the histogram of ${\\mathrm R}$ is close to log-normal, with maximum at ${\\mathrm R = R}_{\\rm m} \\simeq 2,000$, FWHM of about 2 decades and with the entire distribution spanning about 6 decades in the value of ${\\mathrm R}$. We note that the peak of the distribution is close to the proton-to-electron mass ratio $({\\mathrm R}_{\\rm m} \\simeq m_p/m_e = 1836)$, as proposed by us earlier, on the basis of a specific model for the conversion of the GRB blast wave kinetic energy into radiation, before any similar analysis were made. It therefore appears that, in addition to the values of the energy of peak luminos...

  9. Guide to Using the WIND Toolkit Validation Code

    SciTech Connect (OSTI)

    Lieberman-Cribbin, W.; Draxl, C.; Clifton, A.

    2014-12-01T23:59:59.000Z

    In response to the U.S. Department of Energy's goal of using 20% wind energy by 2030, the Wind Integration National Dataset (WIND) Toolkit was created to provide information on wind speed, wind direction, temperature, surface air pressure, and air density on more than 126,000 locations across the United States from 2007 to 2013. The numerical weather prediction model output, gridded at 2-km and at a 5-minute resolution, was further converted to detail the wind power production time series of existing and potential wind facility sites. For users of the dataset it is important that the information presented in the WIND Toolkit is accurate and that errors are known, as then corrective steps can be taken. Therefore, we provide validation code written in R that will be made public to provide users with tools to validate data of their own locations. Validation is based on statistical analyses of wind speed, using error metrics such as bias, root-mean-square error, centered root-mean-square error, mean absolute error, and percent error. Plots of diurnal cycles, annual cycles, wind roses, histograms of wind speed, and quantile-quantile plots are created to visualize how well observational data compares to model data. Ideally, validation will confirm beneficial locations to utilize wind energy and encourage regional wind integration studies using the WIND Toolkit.

  10. Duration distributions for different softness groups of gamma-ray bursts

    E-Print Network [OSTI]

    Y. -P. Qin; A. C. Gupta; J. H. Fan; C. -Y. Su; R. -J. Lu

    2010-10-10T23:59:59.000Z

    Gamma-ray bursts (GRBs) are divided into two classes according to their durations. We investigate if the softness of bursts plays a role in the conventional classification of the objects. We employ the BATSE (Burst and Transient Source Experiment) catalog and analyze the duration distributions of different groups of GRBs associated with distinct softness. Our analysis reveals that the conventional classification of GRBs with the duration of bursts is influenced by the softness of the objects. There exits a bimodality in the duration distribution of GRBs for each group of bursts and the time position of the dip in the bimodality histogram shifts with the softness parameter. Our findings suggest that the conventional classification scheme should be modified by separating the two well-known populations in different softness groups, which would be more reasonable than doing so with a single sample. According to the relation between the dip position and the softness parameter, we get an empirical function that can roughly set apart the short-hard and long-soft bursts: $SP = (0.100 \\pm 0.028) T_{90}^{-(0.85 \\pm 0.18)}$, where $SP$ is the softness parameter adopted in this paper.

  11. Simulation of wind-speed time series for wind-energy conversion analysis.

    SciTech Connect (OSTI)

    Corotis, R.B.

    1982-06-01T23:59:59.000Z

    In order to investigate operating characteristics of a wind energy conversion system it is often desirable to have a sequential record of wind speeds. Sometimes a long enough actual data record is not available at the time an analysis is needed. This may be the case if, e.g., data are recorded three times a day at a candidate wind turbine site, and then the hourly performance of generated power is desired. In such cases it is often possible to use statistical characteristics of the wind speed data to calibrate a stochastic model and then generate a simulated wind speed time series. Any length of record may be simulated by this method, and desired system characteristics may be studied. A simple wind speed simulation model, WEISIM, is developed based on the Weibull probability distribution for wind speeds with a correction based on the lag-one autocorrelation value. The model can simulate at rates from one a second to one an hour, and wind speeds can represent short-term averages (e.g., 1-sec averages) or longer-term averages (e.g., 1-min or 1 hr averages). The validity of the model is verified with PNL data for both histogram characteristics and persistance characteristics.

  12. Population Dose Commitments Due to Radioactive Releases from Nuclear Power Plant Sites in 1977

    SciTech Connect (OSTI)

    Baker, D. A.

    1980-10-01T23:59:59.000Z

    Population radiation dose commitments have been estimated from reported radionuclide releases from commercial power reactors operating during 1977. Fifty-year dose commitments from a one-year exposure were calculated from both liquid and atmospheric releases for four population groups (infant, child, teen-ager and adult) residing between 2 and 80 km from each site. This report tabulates the results of these calculations, showing the dose commitments for both liquid and airborne pathways for each age group and organ, Also included for each site is a histogram showing the fraction of the total population within 2 to 80 km around each site receiving various average dose commitments from the airborne pathways. The total dose commitment from both liquid and airborne pathways ranged from a high of 220 person-rem to a low of 0.003 person-rem with an arithmetic mean of 16 person-rem. The total population dose for all sites was estimated at 700 person-rem for the 92 million people considered at risk. The average individual dose commitment from all pathways on a site basis ranged from a low of 2 x 10{sup -5} mrem to a high of 0.1 mrem. No attempt was made in this study to determine the maximum dose commitment received by any one individual from the radionuclides released at any of the sites.

  13. Population dose commitments due to radioactive releases from Nuclear-Power-Plant Sites in 1979

    SciTech Connect (OSTI)

    Baker, D.A.; Peloquin, R.A.

    1982-12-01T23:59:59.000Z

    Population radiation dose commitments have been estimated from reported radionuclide releases from commercial power reactors operating during 1979. Fifty-year dose commitments from a one-year exposure were calculated from both liquid and atmospheric releases for four population groups (infant, child, teen-ager and adult) residing between 2 and 80 km from each site. This report tabulates the results of these calculations, showing the dose commitments for both liquid and airborne pathways for each age group and organ. Also included for each site is a histogram showing the fraction of the total population within 2 to 80 km around each site receiving various average dose commitments from the airborne pathways. The total dose commitment from both liquid and airborne pathways ranged from a high of 1300 person-rem to a low of 0.0002 person-rem with an arithmetic mean of 38 person-rem. The total population dose for all sites was estimated at 1800 person-rem for the 94 million people considered at risk. The average individual dose commitment from all pathways on a site basis ranged from a low of 2 x 10/sup -6/ mrem to a high of 0.7 mrem. No attempt was made in this study to determine the maximum dose commitment received by any one individual from the radionuclides released at any of the sites.

  14. Population dose commitments due to radioactive releases from nuclear-power-plant sites in 1978

    SciTech Connect (OSTI)

    Peloquin, R.A.; Schwab, J.D.; Baker, D.A.

    1982-06-01T23:59:59.000Z

    Population radiation dose commitments have been estimated from reported radionuclide releases from commercial power reactors operating during 1978. Fifty-year dose commitments from a one-year exposure were calculated from both liquid and atmospheric releases for four population groups (infant, child, teen-ager and adult) residing between 2 and 80 km from each site. This report tabulates the results of these calculations, showing the dose commitments for both liquid and airborne pathways for each age group and organ. Also included for each site is a histogram showing the fraction of the total population within 2 to 80 km around each site receiving various average dose commitments from the airborne pathways. The total dose commitment from both liquid and airborne pathways ranged from a high of 200 person-rem to a low of 0.0004 person-rem with an arithmetic mean of 14 person-rem. The total population dose for allsites was estimated at 660 person-rem for the 93 million people considered at risk. The average individual dose commitment from all pathways on a site basis ranged from a low of 3 x 10/sup -6/ mrem to a high of 0.08 mrem. No attempt was made in this study to determine the maximum dose commitment received by any one individual from the radionuclides released at any of the sites.

  15. Population dose commitments due to radioactive releases from nuclear power plant sites in 1985

    SciTech Connect (OSTI)

    Baker, D.A.

    1988-08-01T23:59:59.000Z

    Population radiation dose commitments have been estimated from reported radionuclide releases from commericial power reactors operating during 1985. Fifty-year dose commitments from a one-year exposure were calculated from both liquid and atmospheric releases for four population groups (infant, child, teen-ager and adult) residing between 2 and 80 km from each of 61 sites. This report tabulates the results of these calculations, showing the dose commitments for both liquid and airborne pathways for each age group and organ. Also included for each of the sites is a histogram showing the fraction of the total population within 2 to 80 km around each site receiving various average dose commitments from the airborne pathways. The total dose commitments (from both liquid and airborne pathways) for each site ranged from a high of 73 person-rem to a low of 0.011 person-rem for the sites with plants operating throughout the year with an arithmetic mean of 3 person-rem. The total population dose for all sites was estimated at 200 person-rem for the 110 million people considered at risk. The site average individual dose commitment from all pathways ranged from a low of 5 /times/ 10/sup /minus/6/ mrem to a high of 0.02 mrem. No attempt was made in this study to determine the maximum dose commitment received by any one individual from the radionuclides released at any of the sites.

  16. Population dose commitments due to radioactive releases from nuclear power plant sites in 1981. Volume 3

    SciTech Connect (OSTI)

    Baker, D.A.; Peloquin, R.A.

    1985-01-01T23:59:59.000Z

    Population radiation dose commitments have been estimated from reported radionuclide releases from commercial power reactors operating during 1981. Fifty-year dose commitments from a one-year exposure were calculated from both liquid and atmospheric releases for four population groups (infant, child, teenager and adult) residing between 2 and 80 km from each site. This report tabulates the results of these calculations, showing the dose commitments for both liquid and airborne pathways for each age group and organ. Also included for each site is a histogram showing the fraction of the total population within 2 to 80 km around each site receiving various average dose commitments from the airborne pathways. The total dose commitment from both liquid and airborne pathways from 48 sites ranged from a high of 20 person-rem to a low of 0.008 person-rem with an arithmetic mean of 3 person-rem. The total population dose for all sites was estimated at 160 person-rem for the 98 million people considered at risk.

  17. Population dose commitments due to radioactive releases from nuclear power plant sites in 1980

    SciTech Connect (OSTI)

    Baker, D.A.; Peloquin, R.A.

    1983-08-01T23:59:59.000Z

    Population radiation dose commitments have been estimated from reported radionuclide releases from commercial power reactors operating during 1980. In addition doses derived from the shutdown reactors at the Three Mile Island site were included. Fifty-year dose commitments from a one-year exposure were calculated from both liquid and atmospheric releases for four population groups (infant, child, teen-ager and adult) residing between 2 and 80 km from each site. This report tabulates the results of these calculations, showing the dose commitments for both liquid and airborne pathways for each age group and organ. Also included for each site is a histogram showing the fraction of the total population within 2 to 80 km around each site receiving various average dose commitments from the airborne pathways. The total dose commitment from both liquid and airborne pathways ranged from a high of 40 person-rem to a low of 0.02 person-rem with an arithmetic mean of 4 person-rem. The total population dose for all sites was estimated at 180 person-rem for the 96 million people considered at risk.

  18. High speed serial link for UA1 microprocessor network

    E-Print Network [OSTI]

    Cittolin, S; Zurfluh, E

    1981-01-01T23:59:59.000Z

    The UA1 data acquisition system consists of a set of distributed microprocessor units. An interprocessor link, independent of the CAMAC data readout, has been developed in order to have continuous remote control and run-time data handling, e.g. transmission of calibration programs/parameters, equipment test/status and histogram accumulation. The data transmission system is designed to be used in a loop configuration equipped with transceivers for twisted pair cables (RS-422). As an economical system, it is running as an ancillary serial loop-link between microprocessors, like Data Acquisition Crate Controllers and systems with distributed intelligence. The software driver consists of a loop-controller package, which may run in a BAMBI Computer Language environment and a fully interrupt controlled program for all other secondary stations. A special single-character mode provides a handy link for remote debugging in a pseudo-full-duplex mode. The format is based on the HDLC protocol without sequence numbering. ...

  19. Anniversary Paper: Image processing and manipulation through the pages of Medical Physics

    SciTech Connect (OSTI)

    Armato, Samuel G. III; Ginneken, Bram van [Department of Radiology, University of Chicago, 5841 South Maryland Avenue, Chicago, Illinois 60637 (United States); Image Sciences Institute, University Medical Center Utrecht, Heidelberglaan 100, Room Q0S.459, 3584 CX Utrecht (Netherlands)

    2008-10-15T23:59:59.000Z

    The language of radiology has gradually evolved from ''the film'' (the foundation of radiology since Wilhelm Roentgen's 1895 discovery of x-rays) to ''the image,'' an electronic manifestation of a radiologic examination that exists within the bits and bytes of a computer. Rather than simply storing and displaying radiologic images in a static manner, the computational power of the computer may be used to enhance a radiologist's ability to visually extract information from the image through image processing and image manipulation algorithms. Image processing tools provide a broad spectrum of opportunities for image enhancement. Gray-level manipulations such as histogram equalization, spatial alterations such as geometric distortion correction, preprocessing operations such as edge enhancement, and enhanced radiography techniques such as temporal subtraction provide powerful methods to improve the diagnostic quality of an image or to enhance structures of interest within an image. Furthermore, these image processing algorithms provide the building blocks of more advanced computer vision methods. The prominent role of medical physicists and the AAPM in the advancement of medical image processing methods, and in the establishment of the ''image'' as the fundamental entity in radiology and radiation oncology, has been captured in 35 volumes of Medical Physics.

  20. Surface forces: Surface roughness in theory and experiment

    SciTech Connect (OSTI)

    Parsons, Drew F., E-mail: Drew.Parsons@anu.edu.au; Walsh, Rick B.; Craig, Vincent S. J. [Department of Applied Mathematics, Research School of Physical Sciences and Engineering, Australian National University, Canberra, ACT 0200 (Australia)] [Department of Applied Mathematics, Research School of Physical Sciences and Engineering, Australian National University, Canberra, ACT 0200 (Australia)

    2014-04-28T23:59:59.000Z

    A method of incorporating surface roughness into theoretical calculations of surface forces is presented. The model contains two chief elements. First, surface roughness is represented as a probability distribution of surface heights around an average surface height. A roughness-averaged force is determined by taking an average of the classic flat-surface force, weighing all possible separation distances against the probability distributions of surface heights. Second the model adds a repulsive contact force due to the elastic contact of asperities. We derive a simple analytic expression for the contact force. The general impact of roughness is to amplify the long range behaviour of noncontact (DLVO) forces. The impact of the elastic contact force is to provide a repulsive wall which is felt at a separation between surfaces that scales with the root-mean-square (RMS) roughness of the surfaces. The model therefore provides a means of distinguishing between “true zero,” where the separation between the average centres of each surface is zero, and “apparent zero,” defined by the onset of the repulsive contact wall. A normal distribution may be assumed for the surface probability distribution, characterised by the RMS roughness measured by atomic force microscopy (AFM). Alternatively the probability distribution may be defined by the histogram of heights measured by AFM. Both methods of treating surface roughness are compared against the classic smooth surface calculation and experimental AFM measurement.

  1. Proton radiation therapy for retinoblastoma: Comparison of various intraocular tumor locations and beam arrangements

    SciTech Connect (OSTI)

    Krengli, Marco [Department of Radiotherapy, University of Piemonte Orientale, Novara (Italy); Hug, Eugen B. [Department of Radiation Oncology, Dartmouth Hitchcock Medical Center, Lebanon, NH (United States); Adams, Judy A. [Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, MA (United States); Smith, Alfred R. [Department of Radiation Physics, University of Texas M.D. Anderson Cancer Center, Houston, TX (United States); Tarbell, Nancy J. [Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, MA (United States); Munzenrider, John E. [Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, MA (United States)]. E-mail: jmunzenrider@partners.org

    2005-02-01T23:59:59.000Z

    Purpose: To study the optimization of proton beam arrangements for various intraocular tumor locations; and to correlate isodose distributions with various target and nontarget structures. Methods and materials: We considered posterior-central, nasal, and temporal tumor locations, with straight, intrarotated, or extrarotated eye positions. Doses of 46 cobalt grey equivalent (CGE) to gross tumor volume (GTV) and 40 CGE to clinical target volume (CTV) (2 CGE per fraction) were assumed. Using three-dimensional planning, we compared isodose distributions for lateral, anterolateral oblique, and anteromedial oblique beams and dose-volume histograms of CTVs, GTVs, lens, lacrimal gland, bony orbit, and soft tissues. Results: All beam arrangements fully covered GTVs and CTVs with optimal lens sparing. Only 15% of orbital bone received doses {>=}20 CGE with a lateral beam, with 20-26 CGE delivered to two of three growth centers. The anterolateral oblique approach with an intrarotated eye resulted in additional reduction of bony volume and exposure of only one growth center. No appreciable dose was delivered to the contralateral eye, brain tissue, or pituitary gland. Conclusions: Proton therapy achieved homogeneous target coverage with true lens sparing. Doses to orbit structures, including bony growth centers, were minimized with different beam arrangements and eye positions. Proton therapy could reduce the risks of second malignancy and cosmetic and functional sequelae.

  2. Proton Radiotherapy for Childhood Ependymoma: Initial Clinical Outcomes and Dose Comparisons

    SciTech Connect (OSTI)

    MacDonald, Shannon M. [Department of Radiation Oncology, Massachusetts General Hospital, Harvard Medical School, Boston, MA (United States)], E-mail: smacdonald@partners.org; Safai, Sairos; Trofimov, Alexei; Wolfgang, John [Department of Radiation Oncology, Massachusetts General Hospital, Harvard Medical School, Boston, MA (United States); Fullerton, Barbara [Department of Otology and Laryngology, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA (United States); Yeap, Beow Y. [Department of Internal Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, MA (United States); Bortfeld, Thomas; Tarbell, Nancy J.; Yock, Torunn [Department of Radiation Oncology, Massachusetts General Hospital, Harvard Medical School, Boston, MA (United States)

    2008-07-15T23:59:59.000Z

    Purpose: To report preliminary clinical outcomes for pediatric patients treated with proton beam radiation for intracranial ependymoma and compare the dose distributions of intensity-modulated radiation therapy with photons (IMRT), three-dimensional conformal proton radiation, and intensity-modulated proton radiation therapy (IMPT) for representative patients. Methods and Materials: All children with intracranial ependymoma confined to the supratentorial or infratentorial brain treated at the Francis H. Burr Proton Facility and Harvard Cyclotron between November 2000 and March 2006 were included in this study. Seventeen patients were treated with protons. Proton, IMRT, and IMPT plans were generated with similar clinical constraints for representative infratentorial and supratentorial ependymoma cases. Tumor and normal tissue dose-volume histograms were calculated and compared. Results: At a median follow-up of 26 months from the start date of radiation therapy, local control, progression-free survival, and overall survival rates were 86%, 80%, and 89%, respectively. Subtotal resection was significantly associated with decreased local control (p = 0.016). Similar tumor volume coverage was achieved with IMPT, proton therapy, and IMRT. Substantial normal tissue sparing was seen with proton therapy compared with IMRT. Use of IMPT will allow for additional sparing of some critical structures. Conclusions: Preliminary disease control with proton therapy compares favorably with the literature. Dosimetric comparisons show the advantage of proton radiation compared with IMRT in the treatment of ependymoma. Further sparing of normal structures appears possible with IMPT. Superior dose distributions were accomplished with fewer beam angles with the use of protons and IMPT.

  3. Gamma Ray Bursts from Minijets

    E-Print Network [OSTI]

    Nir J. Shaviv; Arnon Dar

    1994-07-14T23:59:59.000Z

    Striking similarities exist between high energy gamma ray emission from active galactic nuclei (AGN) and gamma ray bursts (GRBs). They suggest that GRBs are generated by inverse Compton scattering from highly relativistic electrons in transient jets. Such jets may be produced along the axis of an accretion disk formed around stellar black holes (BH) or neutron stars (NS) in BH-NS and NS-NS mergers and in accretion induced collapse of magnetized white dwarfs (WD) or neutron stars in close binary systems. Such events may produce the cosmological GRBs. Transient jets formed by single old magnetized neutron stars in an extended Galactic halo may produce a local population of GRBs. Here we show that jet production of GRBs by inverse Compton scattering can explain quite simply the striking correlations that exist between various temporal features of GRBs, their duration histogram, the power spectrum of their complex multipeak light curves, their power-law high energy spectra and other features of GRBs. Some additional predictions are made including the expected polarization of gamma-rays in the bursts.

  4. Substructure in clusters containing wide-angle tailed radio galaxies. I. New redshifts

    E-Print Network [OSTI]

    Pinkney, J C; Ledlow, M J; Gómez, P L; Hill, J M; Pinkney, Jason; Burns, Jack O.; Ledlow, Michael J.; Gomez, Percy L.; Hill, John M.

    2000-01-01T23:59:59.000Z

    We present new redshifts and positions for 635 galaxies in nine rich clusters containing Wide-Angle Tailed (WAT) radio galaxies. Combined with existing data, we now have a sample of 18 WAT-containing clusters with more than 10 redshifts. This sample contains a substantial portion of the WAT clusters in the VLA 20 cm survey of Abell clusters, including 75% of WAT clusters in the complete survey (z0.09. It is a representative sample which should not contain biases other than selection by radio morphology. We graphically present the new data using histograms and sky maps. A semi-automated procedure is used to search for emission lines in the spectra in order to add and verify galaxy redshifts. We find that the average apparent fraction of emission line galaxies is about 9% in both the clusters and the field. We investigate the magnitude completeness of our redshift surveys with CCD data for a test case, Abell 690. This case indicates that our galaxy target lists are deeper than the detection limit of a typical M...

  5. Substructure in clusters containing wide-angle tailed radio galaxies. I. New redshifts

    E-Print Network [OSTI]

    Jason Pinkney; Jack O. Burns; Michael J. Ledlow; Percy L. Gomez; John M. Hill

    2000-11-08T23:59:59.000Z

    We present new redshifts and positions for 635 galaxies in nine rich clusters containing Wide-Angle Tailed (WAT) radio galaxies. Combined with existing data, we now have a sample of 18 WAT-containing clusters with more than 10 redshifts. This sample contains a substantial portion of the WAT clusters in the VLA 20 cm survey of Abell clusters, including 75% of WAT clusters in the complete survey (z0.09. It is a representative sample which should not contain biases other than selection by radio morphology. We graphically present the new data using histograms and sky maps. A semi-automated procedure is used to search for emission lines in the spectra in order to add and verify galaxy redshifts. We find that the average apparent fraction of emission line galaxies is about 9% in both the clusters and the field. We investigate the magnitude completeness of our redshift surveys with CCD data for a test case, Abell 690. This case indicates that our galaxy target lists are deeper than the detection limit of a typical MX exposure, and they are 82% complete down to R=19.0. The importance of the uniformity of the placement of fibers on targets is posited, and we evaluate this in our datasets. We find some cases of non-uniformities which may influence dynamical analyses. A second paper will use this database to look for correlations between the WAT radio morphology and the cluster's dynamical state.

  6. Development and evaluation of an automated reflectance microscope system for the petrographic characterization of bituminous coals

    SciTech Connect (OSTI)

    Hoover, D. S.; Davis, A.

    1980-10-01T23:59:59.000Z

    The development of automated coal petrographic techniques will lessen the demands on skilled personnel to do routine work. This project is concerned with the development and successful testing of an instrument which will meet these needs. The fundamental differences in reflectance of the three primary maceral groups should enable their differentiation in an automated-reflectance frequency histogram (reflectogram). Consequently, reflected light photometry was chosen as the method for automating coal petrographic analysis. Three generations of an automated system (called Rapid Scan Versions I, II and III) were developed and evaluated for petrographic analysis. Their basic design was that of a reflected-light microscope photometer with an automatic stage, interfaced with a minicomputer. The hardware elements used in the Rapid Scan Version I limited the system's flexibility and presented problems with signal digitization and measurement precision. Rapid Scan Version II was designed to incorporate a new microscope photometer and computer system. A digital stepping stage was incorporated into the Rapid Scan Version III system. The precision of reflectance determination of this system was found to be +- 0.02 percent reflectance. The limiting factor in quantitative interpretation of Rapid Scan reflectograms is the resolution of reflectance populations of the individual maceral groups. Statistical testing indicated that reflectograms were highly reproducible, and a new computer program, PETAN, was written to interpret the curves for vitrinite reflectance parameters ad petrographic.

  7. ICOOL: A SIMULATION CODE FOR IONIZATION COOLING OF MUON BEAMS.

    SciTech Connect (OSTI)

    FERNOW,R.C.

    1999-03-25T23:59:59.000Z

    Current ideas [1,2] for designing a high luminosity muon collider require significant cooling of the phase space of the muon beams. The only known method that can cool the beams in a time comparable to the muon lifetime is ionization cooling [3,4]. This method requires directing the particles in the beam at a large angle through a low Z absorber material in a strong focusing magnetic channel and then restoring the longitudinal momentum with an rf cavity. We have developed a new 3-D tracking code ICOOL for examining possible configurations for muon cooling. A cooling system is described in terms of a series of longitudinal regions with associated material and field properties. The tracking takes place in a coordinate system that follows a reference orbit through the system. The code takes into account decays and interactions of {approx}50-500 MeV/c muons in matter. Material geometry regions include cylinders and wedges. A number of analytic models are provided for describing the field configurations. Simple diagnostics are built into the code, including calculation of emittances and correlations, longitudinal traces, histograms and scatter plots. A number of auxiliary files can be generated for post-processing analysis by the user.

  8. Filtergraph: An Interactive Web Application for Visualization of Astronomy Datasets

    E-Print Network [OSTI]

    Burger, Dan; Pepper, Joshua; Siverd, Robert J; Paegert, Martin; De Lee, Nathan M

    2013-01-01T23:59:59.000Z

    Filtergraph is a web application being developed and maintained by the Vanderbilt Initiative in Data-intensive Astrophysics (VIDA) to flexibly and rapidly visualize a large variety of astronomy datasets of various formats and sizes. The user loads a flat-file dataset into Filtergraph which automatically generates an interactive data portal that can be easily shared with others. From this portal, the user can immediately generate scatter plots of up to 5 dimensions as well as histograms and tables based on the dataset. Key features of the portal include intuitive controls with auto-completed variable names, the ability to filter the data in real time through user-specified criteria, the ability to select data by dragging on the screen, and the ability to perform arithmetic operations on the data in real time. To enable seamless data visualization and exploration, changes are quickly rendered on screen and visualizations can be exported as high quality graphics files. The application is optimized for speed in t...

  9. Wavelet analysis of MCG-6-30-15 and NGC 4051: a possible discovery of QPOs in 2:1 and 3:2 resonance

    E-Print Network [OSTI]

    Pawel Lachowicz; Bozena Czerny; Marek A. Abramowicz

    2006-07-26T23:59:59.000Z

    Following our previous work of Lachowicz & Czerny (2005), we explore further the application of the continuous wavelet transform to X-ray astronomical signals. Using the public archive of the XMM-Newton satellite, we analyze all available EPIC-pn observations for nearby Seyfert 1 galaxies MCG-6-30-15 and NGC 4051. We confine our analysis to 0.002-0.007 Hz frequency band in which, on the way of theoretically motivated premises, some quasi-periodic oscillations (QPOs) are expected to be found. We find that indeed wavelet power histogram analysis reveals such QPOs centered at two frequencies of ~2.5E-3 Hz and 4-6E-3 Hz, respectively. We show that these quasi-periodic features can be disentangled from the Poisson noise contamination level what is hardly to achieve with the standard Fourier analysis. Interestingly, we find some of them to be in 2:1 or 3:2 ratio. If real, our finding may be considered as a link between QPOs observed in AGN and kHz QPOs seen in X-ray binary systems.

  10. Virtual data in CMS analysis

    SciTech Connect (OSTI)

    A. Arbree et al.

    2003-10-01T23:59:59.000Z

    The use of virtual data for enhancing the collaboration between large groups of scientists is explored in several ways: by defining ''virtual'' parameter spaces which can be searched and shared in an organized way by a collaboration of scientists in the course of their analysis; by providing a mechanism to log the provenance of results and the ability to trace them back to the various stages in the analysis of real or simulated data; by creating ''check points'' in the course of an analysis to permit collaborators to explore their own analysis branches by refining selections, improving the signal to background ratio, varying the estimation of parameters, etc.; by facilitating the audit of an analysis and the reproduction of its results by a different group, or in a peer review context. We describe a prototype for the analysis of data from the CMS experiment based on the virtual data system Chimera and the object-oriented data analysis framework ROOT. The Chimera system is used to chain together several steps in the analysis process including the Monte Carlo generation of data, the simulation of detector response, the reconstruction of physics objects and their subsequent analysis, histogramming and visualization using the ROOT framework.

  11. Analysis of Fermi Gamma-Ray Burst duration distribution

    E-Print Network [OSTI]

    Tarnopolski, Mariusz

    2015-01-01T23:59:59.000Z

    Two classes of GRBs, short and long, have been determined without any doubts, and are usually prescribed to different physical scenarios. A third class, intermediate in $T_{90}$ durations, has been reported to be present in the datasets of BATSE, Swift, RHESSI and possibly BeppoSAX. The latest release of $>1500$ GRBs observed by Fermi gives an opportunity to further investigate the duration distribution. The aim of this paper is to investigate whether a third class is present in the $\\log T_{90}$ distribution, or is it described by a bimodal distribution. A standard $\\chi^2$ fitting of a mixture of Gaussians is applied to 25 histograms with different binnings. Different binnings give various values of the fitting parameters, as well as the shape of the fitted curve. Among five statistically significant fits none is trimodal. Locations of the Gaussian components are in agreement with previous works. However, a trimodal distribution, understood in the sense of having three separated peaks, is not found for any ...

  12. Monte Carlo Study of Patchy Nanostructures Self-Assembled from a Single Multiblock Chain

    E-Print Network [OSTI]

    Jakub Krajniak; Michal Banaszak

    2014-10-15T23:59:59.000Z

    We present a lattice Monte Carlo simulation for a multiblock copolymer chain of length N=240 and microarchitecture $(10-10)_{12}$.The simulation was performed using the Monte Carlo method with the Metropolis algorithm. We measured average energy, heat capacity, the mean squared radius of gyration, and the histogram of cluster count distribution. Those quantities were investigated as a function of temperature and incompatibility between segments, quantified by parameter {\\omega}. We determined the temperature of the coil-globule transition and constructed the phase diagram exhibiting a variety of patchy nanostructures. The presented results yield a qualitative agreement with those of the off-lattice Monte Carlo method reported earlier, with a significant exception for small incompatibilities,{\\omega}, and low temperatures, where 3-cluster patchy nanostructures are observed in contrast to the 2-cluster structures observed for the off-lattice $(10-10)_{12}$ chain. We attribute this difference to a considerable stiffness of lattice chains in comparison to that of the off-lattice chains.

  13. Nucleation, transition, and maturing of the self-assembled Au droplets on various type-A GaAs substrates

    SciTech Connect (OSTI)

    Li, Ming-Yu, E-mail: mingyuli.oliver@gmail.com; Sui, Mao; Kim, Eun-Soo [College of Electronics and Information, Kwangwoon University, Nowon-gu, Seoul 139-701 (Korea, Republic of); Lee, Jihoon, E-mail: jihoonleenano@gmail.com [College of Electronics and Information, Kwangwoon University, Nowon-gu, Seoul 139-701 (Korea, Republic of); Institute of Nanoscale Science and Engineering, University of Arkansas, Fayetteville, Arkansas 72701 (United States)

    2014-08-28T23:59:59.000Z

    In this study, the fabrication of self-assembled Au droplets is successfully demonstrated on various type-A GaAs substrates: (711)A, (511)A, (411)A, and (311)A. The nucleation of the self-assembled tiny Au clusters is observed at 300?°C. As an intermediate stage, corrugated Au nanostructures are clearly observed at 350?°C on various type-A GaAs surfaces, rarely witnessed on other substrates. Based on the Volmer-Weber growth mode, the dome-shaped Au droplets with excellent uniformities are successfully fabricated between 500 and 550?°C. As a function of annealing temperature, the self-assembled Au droplets show the increased dimensions including average height and diameter, compensated by the decreased average density. Depending on the substrate indices utilized, the size and density of Au droplets show clear differences throughout the whole temperature range. The results are symmetrically analyzed by using atomic force microscope images, cross-sectional line-profiles, size and density plots, height distribution histograms, and Fourier filter transform power spectra.

  14. States that "look the same" with respect to every basis in a mutually unbiased set

    E-Print Network [OSTI]

    Ilya Amburg; Roshan Sharma; Daniel Sussman; William K. Wootters

    2015-03-18T23:59:59.000Z

    A complete set of mutually unbiased bases in a Hilbert space of dimension $d$ defines a set of $d+1$ orthogonal measurements. Relative to such a set, we define a "MUB-balanced state" to be a pure state for which the list of probabilities of the $d$ outcomes of one of these measurements is independent of the choice of measurement, up to permutations. In this paper we explicitly construct a MUB-balanced state for each prime power dimension $d$ for which $d = 3$ (mod 4). These states have already been constructed by Appleby in unpublished notes, but our presentation here is different in that both the expression for the states themselves and the proof of MUB-balancedness are given in terms of the discrete Wigner function, rather than the density matrix or state vector. The discrete Wigner functions of these states are "rotationally symmetric" in a sense roughly analogous to the rotational symmetry of the energy eigenstates of a harmonic oscillator in the continuous two-dimensional phase space. Upon converting the Wigner function to a density matrix, we find that the states are expressible as real state vectors in the standard basis. We observe numerically that when $d$ is large (and not a power of 3), a histogram of the components of such a state vector appears to form a semicircular distribution.

  15. Variation in DNA content of blood cells of largemouth bass from contaminated and uncontaminated waters

    SciTech Connect (OSTI)

    Lingenfelser, S.F. [Fish and Wildlife Service, White Marsh, VA (United States); Dallas, C.E. [Univ. of Georgia, Athens, GA (United States). Dept. of Pharmacology and Toxicology; Jagoe, C.H.; Smith, M.H.; Brisbin, I.L. Jr.; Chesser, R.K. [Savannah River Ecology Lab., Aiken, SC (United States)

    1997-10-01T23:59:59.000Z

    Largemouth bass (Micropterus salmoides) were collected from locations with and without documented histories of pollution in Georgia and South Carolina. Whole blood samples were collected from over 3,000 bass and analyzed by flow cytometry to measure changes in cellular DNA content and cell cycle distribution. The coefficient of variation (CV) of the cell cycle phase G{sub 0}G{sub 1} peak was used as a measure of variation in DNA content within an individual. The mean CV varied significantly among locations, and some locations with known chemical or radioactive contaminants had higher CVs. Plotting the frequency distribution of CV values for each site revealed greater skewness and kurtosis in most locations with known contaminants. In each case, a right skewness indicated higher proportions of bass with unusually high CV in these locations. Aneuploid-like patterns were detected in the DNA histograms of five fish, all from locations with histories of contamination. The percentage of cells distributed among phases of the cell cycle (G{sub 0}/G{sub 1}, S, and G{sub 2}M) varied significantly among locations, but there was no apparent relationship to contaminant distribution. Differences in CV and frequency of aneuploids among sites with and without histories of pollution were generally small, but increased variation in DNA content may be associated with contaminant exposure at some locations.

  16. A study of self organized criticality in ion temperature gradient mode driven gyrokinetic turbulence

    SciTech Connect (OSTI)

    Mavridis, M.; Isliker, H.; Vlahos, L. [Section of Astrophysics, Astronomy and Mechanics, Department of Physics, Aristotle University of Thessaloniki, GR-54124 Thessaloniki (Greece); Görler, T.; Jenko, F.; Told, D. [Max Planck Institute for Plasma Physics, Boltzmannstr. 2, 85748 Garching (Germany)

    2014-10-15T23:59:59.000Z

    An investigation on the characteristics of self organized criticality (Soc) in ITG mode driven turbulence is made, with the use of various statistical tools (histograms, power spectra, Hurst exponents estimated with the rescaled range analysis, and the structure function method). For this purpose, local non-linear gyrokinetic simulations of the cyclone base case scenario are performed with the GENE software package. Although most authors concentrate on global simulations, which seem to be a better choice for such an investigation, we use local simulations in an attempt to study the locally underlying mechanisms of Soc. We also study the structural properties of radially extended structures, with several tools (fractal dimension estimate, cluster analysis, and two dimensional autocorrelation function), in order to explore whether they can be characterized as avalanches. We find that, for large enough driving temperature gradients, the local simulations exhibit most of the features of Soc, with the exception of the probability distribution of observables, which show a tail, yet they are not of power-law form. The radial structures have the same radial extent at all temperature gradients examined; radial motion (transport) though appears only at large temperature gradients, in which case the radial structures can be interpreted as avalanches.

  17. Baryonic fraction in the cold plus hot dark matter universe

    E-Print Network [OSTI]

    Eunwoo Choi; Dongsu Ryu

    1997-10-08T23:59:59.000Z

    We report a study to constrain the fraction of baryonic matter in the cold plus hot dark matter (CHDM) universe by numerical simulations which include the hydrodynamics of baryonic matter as well as the particle dynamics of dark matter. Spatially flat, COBE-normalized CHDM models with the fraction of hot component $\\Omega_h\\leq0.2$ are considered. We show that the models with $h/n/\\Omega_h=0.5/0.9/0.1$ and $0.5/0.9/0.2$ give a linear power spectrum which agrees well with observations. Here, $h$ is the Hubble constant in unit of $100~km/s/Mpc$ and $n$ is the spectral index of the initial power spectrum. Then, for the models with $h/n/\\Omega_h=0.5/0.9/0.2$ and baryonic fraction $\\Omega_b=0.05$ and 0.1 we calculate the properties of X-ray clusters, such as luminosity function, temperature distribution function, luminosity-temperature relation, histogram of gas to total mass ratio, and change of average temperature with redshift $z$. Comparison with the observed data of X-ray clusters indicates that the model with $\\Omega_b=0.05$ is preferred. The COBE-normalized CHDM model with $\\Omega_b>0.1$ may be ruled out by the present work, since it produces too many X-ray bright clusters.

  18. Radiation-induced complications in prostate cancer patients treated with radiotherapy

    SciTech Connect (OSTI)

    Azuddin, A. Yusof [School of Applied Physics, Faculty of Sciences and Technology, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor, Malaysia and Faculty of Health Sciences, Universiti Kebangsaan Malaysia, 53000 Kuala Lumpur (Malaysia); Rahman, I. Abdul; Mohamed, F. [School of Applied Physics, Faculty of Sciences and Technology, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor (Malaysia); Siah, N. J. [Faculty of Health Sciences, Universiti Kebangsaan Malaysia, 53000 Kuala Lumpur (Malaysia); Saadc, M. [Department of Oncology, University Malaya Medical Center, 50603 Kuala Lumpur (Malaysia); Ismail, F. [Department of Oncology and Radiotherapy, Universiti Kebangsaan Malaysia Medical Centre, 56000 Cheras, Kuala Lumpur (Malaysia)

    2014-09-03T23:59:59.000Z

    The purpose of the study is to determine the relationship between radiation-induced complications with dosimetric and radiobiological parameters for prostate cancer patients that underwent the conformal radiotherapy treatment. 17 prostate cancer patients that have been treated with conformal radiotherapy were retrospectively analysed. The dosimetric data was retrieved in the form of dose-volume histogram (DVH) from Radiotherapy Treatment Planning System. The DVH was utilised to derived Normal Tissue Complication Probability (NTCP) in radiobiological data. Follow-up data from medical records were used to grade the occurrence of acute gastrointestinal (GI) and genitourinary (GU) complications using Radiation Therapy Oncology Group (RTOG) scoring system. The chi-square test was used to determine the relationship between radiation-induced complication with dosimetric and radiobiological parameters. 8 (47%) and 7 (41%) patients were having acute GI and GU complications respectively. The acute GI complication can be associated with V60{sub rectum}, rectal mean dose and NTCP{sub rectum} with p-value of 0.016, 0.038 and 0.049 respectively. There are no significant relationships of acute GU complication with dosimetric and radiobiological variables. Further study can be done by increase the sample size and follow up duration for deeper understanding of the factors that effecting the GU and GI complication in prostate cancer radiotherapy.

  19. Comparison of Prostate IMRT and VMAT Biologically Optimised Treatment Plans

    SciTech Connect (OSTI)

    Hardcastle, Nicholas, E-mail: hardcastle@humonc.wisc.edu [Centre for Medical Radiation Physics, University of Wollongong, NSW (Australia); Department of Human Oncology and Medical Physics, University of Wisconsin-Madison, WI (United States); Tome, Wolfgang A. [Centre for Medical Radiation Physics, University of Wollongong, NSW (Australia); Department of Human Oncology and Medical Physics, University of Wisconsin-Madison, WI (United States); Foo, Kerwyn [Centre for Medical Radiation Physics, University of Wollongong, NSW (Australia); Illawarra Cancer Care Centre, Wollongong Hospital, Wollongong, NSW (Australia); Graduate School of Medicine, University of Wollongong, Wollongong, NSW (Australia); Miller, Andrew [Illawarra Cancer Care Centre, Wollongong Hospital, Wollongong, NSW (Australia); Graduate School of Medicine, University of Wollongong, Wollongong, NSW (Australia); Carolan, Martin [Illawarra Cancer Care Centre, Wollongong Hospital, Wollongong, NSW (Australia); Metcalfe, Peter [Centre for Medical Radiation Physics, University of Wollongong, NSW (Australia)

    2011-10-01T23:59:59.000Z

    Recently, a new radiotherapy delivery technique has become clinically available-volumetric modulated arc therapy (VMAT). VMAT is the delivery of IMRT while the gantry is in motion using dynamic leaf motion. The perceived benefit of VMAT over IMRT is a reduction in delivery time. In this study, VMAT was compared directly with IMRT for a series of prostate cases. For 10 patients, a biologically optimized seven-field IMRT plan was compared with a biologically optimized VMAT plan using the same planning objectives. The Pinnacle RTPS was used. The resultant target and organ-at-risk dose-volume histograms (DVHs) were compared. The normal tissue complication probability (NTCP) for the IMRT and VMAT plans was calculated for 3 model parameter sets. The delivery efficiency and time for the IMRT and VMAT plans was compared. The VMAT plans resulted in a statistically significant reduction in the rectal V25Gy parameter of 8.2% on average over the IMRT plans. For one of the NTCP parameter sets, the VMAT plans had a statistically significant lower rectal NTCP. These reductions in rectal dose were achieved using 18.6% fewer monitor units and a delivery time reduction of up to 69%. VMAT plans resulted in reductions in rectal doses for all 10 patients in the study. This was achieved with significant reductions in delivery time and monitor units. Given the target coverage was equivalent, the VMAT plans were superior.

  20. An applied light-beam induced current study of dye-sensitised solar cells: Photocurrent uniformity mapping and true photoactive area evaluation

    SciTech Connect (OSTI)

    Jones, Timothy W., E-mail: tim.jones@csiro.au; Anderson, Kenrick F.; Duck, Benjamin C.; Wilson, Gregory J. [CSIRO Energy Flagship, Mayfield West, NSW 2304 (Australia); Feron, Krishna [CSIRO Energy Flagship, Mayfield West, NSW 2304 (Australia); Centre for Organic Electronics, The University of Newcastle, Callaghan, NSW 2308 (Australia)

    2014-07-28T23:59:59.000Z

    The conditions for light-beam induced current (LBIC) measurement were experimentally optimised for dye-sensitised solar cells. The impacts of too fast a laser diode modulation frequency (f) and too short a dwell time (t{sub 0}) were investigated for their distortions, artefacts, and noise on the overall photocurrent map image. Optimised mapping conditions for fastest measurement were obtained at a f?=?15?Hz and t{sub 0}?=?900?ms. Whole device maps (nominal area 4?×?4?mm{sup 2}) were obtained on devices in which fabrication defects were intentionally induced. The defects were readily resolved with the LBIC setup and conditions. The inclusion of defects had the effect of broadening the photocurrent distribution and producing a sub-optimal tail to photocurrent histograms. Photoactive areas were derived from LBIC maps and were larger than those predicted by the projected screen printing pattern by up to 25%, which has obvious implications for efficiency measurements made on nominal projected active area.

  1. Nanoscale mapping of the W/Si(001) Schottky barrier

    SciTech Connect (OSTI)

    Durcan, Chris A.; Balsano, Robert; LaBella, Vincent P., E-mail: vlabella@albany.edu [College of Nanoscale Science and Engineering, State University of New York, Albany, New York 12203 (United States)

    2014-07-14T23:59:59.000Z

    The W/Si(001) Schottky barrier was spatially mapped with nanoscale resolution using ballistic electron emission microscopy (BEEM) and ballistic hole emission microscopy (BHEM) using n-type and p-type silicon substrates. The formation of an interfacial tungsten silicide is observed utilizing transmission electron microscopy and Rutherford backscattering spectrometry. The BEEM and BHEM spectra are fit utilizing a linearization method based on the power law BEEM model using the Prietsch Ludeke fitting exponent. The aggregate of the Schottky barrier heights from n-type (0.71?eV) and p-type (0.47?eV) silicon agrees with the silicon band gap at 80?K. Spatially resolved maps of the Schottky barrier are generated from grids of 7225 spectra taken over a 1??m?×?1??m area and provide insight into its homogeneity. Histograms of the barrier heights have a Gaussian component consistent with an interface dipole model and show deviations that are localized in the spatial maps and are attributed to compositional fluctuations, nanoscale defects, and foreign materials.

  2. Analysis of well test data---Application of probabilistic models to infer hydraulic properties of fractures. [Contains list of standardized terminology or nomenclatue used in statistical models

    SciTech Connect (OSTI)

    Osnes, J.D. (RE/SPEC, Inc., Rapid City, SD (United States)); Winberg, A.; Andersson, J.E.; Larsson, N.A. (Sveriges Geologiska AB, Goeteborg (Sweden))

    1991-09-27T23:59:59.000Z

    Statistical and probabilistic methods for estimating the probability that a fracture is nonconductive (or equivalently, the conductive-fracture frequency) and the distribution of the transmissivities of conductive fractures from transmissivity measurements made in single-hole injection (well) tests were developed. These methods were applied to a database consisting of over 1,000 measurements made in nearly 25 km of borehole at five sites in Sweden. The depths of the measurements ranged from near the surface to over 600-m deep, and packer spacings of 20- and 25-m were used. A probabilistic model that describes the distribution of a series of transmissivity measurements was derived. When the parameters of this model were estimated using maximum likelihood estimators, the resulting estimated distributions generally fit the cumulative histograms of the transmissivity measurements very well. Further, estimates of the mean transmissivity of conductive fractures based on the maximum likelihood estimates of the model's parameters were reasonable, both in magnitude and in trend, with respect to depth. The estimates of the conductive fracture probability were generated in the range of 0.5--5.0 percent, with the higher values at shallow depths and with increasingly smaller values as depth increased. An estimation procedure based on the probabilistic model and the maximum likelihood estimators of its parameters was recommended. Some guidelines regarding the design of injection test programs were drawn from the recommended estimation procedure and the parameter estimates based on the Swedish data. 24 refs., 12 figs., 14 tabs.

  3. SU-E-J-256: Dual Energy Planar Image Based Localization in the Absence of On-Board CT Images

    SciTech Connect (OSTI)

    Sadagopan, R; Yang, J; Li, H [M.D. Anderson Cancer Center, Houston, TX (United States)

    2014-06-01T23:59:59.000Z

    Purpose: To develop a tool enabling soft tissue based image guidance using dual energy radiographs for cases when on-board CT is not available. Method: Dual energy planar radiographs can be applied to image guidance for targeting lung lesions because the bone based alignment only may not be sufficient as the lesions move. We acquired images of an anthropomorphic thorax phantom at 120 and 60 KVp respectively. Using a weighted logarithmic subtraction of these dual energy images, a soft tissue enhanced and a bone enhanced image were generated and they could be used for the image guidance purpose. Similar processing was also applied to a dual energy image set acquired for a patient undergoing a proton therapy. Results: The soft tissue enhanced images suppressed bones (ribs and scapula) overlying on lung, thus enabling a better visualization of soft tissue and lesion, while the bone enhanced image suppressed the soft tissue. These enhanced effects were visually apparent without further processing for display enhancements, such as using histogram or edge enhancement technique. Conclusions: The phantom image processing was encouraging. The initial test on the patient image set showed that other post processing might still be able to add value in visualizing soft tissues in addition to the dual energy soft tissue enhancement. More evaluations are needed to determine the potential benefit of this technique in the clinic.

  4. Maximum-likelihood density modification using pattern recognition of structural motifs

    SciTech Connect (OSTI)

    Terwilliger, Thomas C., E-mail: terwilliger@lanl.gov [Bioscience Division, Mail Stop M888, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States)

    2001-12-01T23:59:59.000Z

    A likelihood-based density-modification method is extended to include pattern recognition of structural motifs. The likelihood-based approach to density modification [Terwilliger (2000 ?), Acta Cryst. D56, 965–972] is extended to include the recognition of patterns of electron density. Once a region of electron density in a map is recognized as corresponding to a known structural element, the likelihood of the map is reformulated to include a term that reflects how closely the map agrees with the expected density for that structural element. This likelihood is combined with other aspects of the likelihood of the map, including the presence of a flat solvent region and the electron-density distribution in the protein region. This likelihood-based pattern-recognition approach was tested using the recognition of helical segments in a largely helical protein. The pattern-recognition method yields a substantial phase improvement over both conventional and likelihood-based solvent-flattening and histogram-matching methods. The method can potentially be used to recognize any common structural motif and incorporate prior knowledge about that motif into density modification.

  5. Decision-Making in Structure Solution using Bayesian Estimates of Map Quality: The PHENIX AutoSol Wizard

    SciTech Connect (OSTI)

    Terwilliger, T. C.; Adams, P. D.; Read, R. J.; McCoy, A. J.; Moriarty, Nigel W.; Grosse-Kunstleve, R. W.; Afonine, P. V.; Zwart, P. H.; Hung, L.-W.

    2009-03-01T23:59:59.000Z

    Estimates of the quality of experimental maps are important in many stages of structure determination of macromolecules. Map quality is defined here as the correlation between a map and the map calculated based on a final refined model. Here we examine 10 different measures of experimental map quality using a set of 1359 maps calculated by reanalysis of 246 solved MAD, SAD, and MIR datasets. A simple Bayesian approach to estimation of map quality from one or more measures is presented. We find that a Bayesian estimator based on the skew of histograms of electron density is the most accurate of the 10 individual Bayesian estimators of map quality examined, with a correlation between estimated and actual map quality of 0.90. A combination of the skew of electron density with the local correlation of rms density gives a further improvement in estimating map quality, with an overall correlation coefficient of 0.92. The PHENIX AutoSol Wizard carries out automated structure solution based on any combination of SAD, MAD, SIR, or MIR datasets. The Wizard is based on tools from the PHENIX package and uses the Bayesian estimates of map quality described here to choose the highest-quality solutions after experimental phasing.

  6. Maximum-likelihood density modification

    SciTech Connect (OSTI)

    Terwilliger, Thomas C., E-mail: terwilliger@lanl.gov [Structural Biology Group, Mail Stop M888, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States)

    2000-08-01T23:59:59.000Z

    A likelihood-based density modification approach is developed that can incorporate expected electron-density information from a wide variety of sources. A likelihood-based approach to density modification is developed that can be applied to a wide variety of cases where some information about the electron density at various points in the unit cell is available. The key to the approach consists of developing likelihood functions that represent the probability that a particular value of electron density is consistent with prior expectations for the electron density at that point in the unit cell. These likelihood functions are then combined with likelihood functions based on experimental observations and with others containing any prior knowledge about structure factors to form a combined likelihood function for each structure factor. A simple and general approach to maximizing the combined likelihood function is developed. It is found that this likelihood-based approach yields greater phase improvement in model and real test cases than either conventional solvent flattening and histogram matching or a recent reciprocal-space solvent-flattening procedure [Terwilliger (1999 ?), Acta Cryst. D55, 1863–1871].

  7. Small Bowel Dose Parameters Predicting Grade ?3 Acute Toxicity in Rectal Cancer Patients Treated With Neoadjuvant Chemoradiation: An Independent Validation Study Comparing Peritoneal Space Versus Small Bowel Loop Contouring Techniques

    SciTech Connect (OSTI)

    Banerjee, Robyn, E-mail: robynbanerjee@gmail.com [Department of Radiation Oncology, Tom Baker Cancer Centre, University of Calgary, Calgary, Alberta (Canada)] [Department of Radiation Oncology, Tom Baker Cancer Centre, University of Calgary, Calgary, Alberta (Canada); Chakraborty, Santam; Nygren, Ian; Sinha, Richie [Department of Radiation Oncology, Tom Baker Cancer Centre, University of Calgary, Calgary, Alberta (Canada)] [Department of Radiation Oncology, Tom Baker Cancer Centre, University of Calgary, Calgary, Alberta (Canada)

    2013-04-01T23:59:59.000Z

    Purpose: To determine whether volumes based on contours of the peritoneal space can be used instead of individual small bowel loops to predict for grade ?3 acute small bowel toxicity in patients with rectal cancer treated with neoadjuvant chemoradiation therapy. Methods and Materials: A standardized contouring method was developed for the peritoneal space and retrospectively applied to the radiation treatment plans of 67 patients treated with neoadjuvant chemoradiation therapy for rectal cancer. Dose-volume histogram (DVH) data were extracted and analyzed against patient toxicity. Receiver operating characteristic analysis and logistic regression were carried out for both contouring methods. Results: Grade ?3 small bowel toxicity occurred in 16% (11/67) of patients in the study. A highly significant dose-volume relationship between small bowel irradiation and acute small bowel toxicity was supported by the use of both small bowel loop and peritoneal space contouring techniques. Receiver operating characteristic analysis demonstrated that, for both contouring methods, the greatest sensitivity for predicting toxicity was associated with the volume receiving between 15 and 25 Gy. Conclusion: DVH analysis of peritoneal space volumes accurately predicts grade ?3 small bowel toxicity in patients with rectal cancer receiving neoadjuvant chemoradiation therapy, suggesting that the contours of the peritoneal space provide a reasonable surrogate for the contours of individual small bowel loops. The study finds that a small bowel V15 less than 275 cc and a peritoneal space V15 less than 830 cc are associated with a less than 10% risk of grade ?3 acute toxicity.

  8. Spinal Cord Tolerance in the Age of Spinal Radiosurgery: Lessons From Preclinical Studies

    SciTech Connect (OSTI)

    Medin, Paul M., E-mail: Paul.medin@utsouthwestern.ed [Department of Radiation Oncology, UT Southwestern Medical Center, Dallas, TX (United States); Boike, Thomas P. [Department of Radiation Oncology, UT Southwestern Medical Center, Dallas, TX (United States)

    2011-04-01T23:59:59.000Z

    Clinical implementation of spinal radiosurgery has increased rapidly in recent years, but little is known regarding human spinal cord tolerance to single-fraction irradiation. In contrast, preclinical studies in single-fraction spinal cord tolerance have been ongoing since the 1970s. The influences of field length, dose rate, inhomogeneous dose distributions, and reirradiation have all been investigated. This review summarizes literature regarding single-fraction spinal cord tolerance in preclinical models with an emphasis on practical clinical significance. The outcomes of studies that incorporate uniform irradiation are surprisingly consistent among multiple small- and large-animal models. Extensive investigation of inhomogeneous dose distributions in the rat has demonstrated a significant dose-volume effect while preliminary results from one pig study are contradictory. Preclinical spinal cord dose-volume studies indicate that dose distribution is more critical than the volume irradiated suggesting that neither dose-volume histogram analysis nor absolute volume constraints are effective in predicting complications. Reirradiation data are sparse, but results from guinea pig, rat, and pig studies are consistent with the hypothesis that the spinal cord possesses a large capacity for repair. The mechanisms behind the phenomena observed in spinal cord studies are not readily explained and the ability of dose response models to predict outcomes is variable underscoring the need for further investigation. Animal studies provide insight into the phenomena and mechanisms of radiosensitivity but the true significance of animal studies can only be discovered through clinical trials.

  9. Investigating the solid-liquid phase transition of water nanofilms using the generalized replica exchange method

    SciTech Connect (OSTI)

    Lu, Qing [Division of Materials Science and Engineering, Boston University, Brookline, Massachusetts 02446 (United States); Kim, Jaegil; Straub, John E., E-mail: straub@bu.edu [Department of Chemistry, Boston University, Boston, Massachusetts 02215 (United States); Farrell, James D.; Wales, David J. [University Chemical Laboratories, Lensfield Road, Cambridge CB2 1EW (United Kingdom)

    2014-11-14T23:59:59.000Z

    The generalized Replica Exchange Method (gREM) was applied to study a solid-liquid phase transition in a nanoconfined bilayer water system using the monatomic water (mW) model. Exploiting optimally designed non-Boltzmann sampling weights with replica exchanges, gREM enables an effective sampling of configurations that are metastable or unstable in the canonical ensemble via successive unimodal energy distributions across phase transition regions, often characterized by S-loop or backbending in the statistical temperature. Extensive gREM simulations combined with Statistical Temperature Weighted Histogram Analysis Method (ST-WHAM) for nanoconfined mW water at various densities provide a comprehensive characterization of diverse thermodynamic and structural properties intrinsic to phase transitions. Graph representation of minimized structures of bilayer water systems determined by the basin-hopping global optimization revealed heterogeneous ice structures composed of pentagons, hexagons, and heptagons, consistent with an increasingly ordered solid phase with decreasing density. Apparent crossover from a first-order solid-liquid transition to a continuous one in nanoconfined mW water with increasing density of the system was observed in terms of a diminishing S-loop in the statistical temperature, smooth variation of internal energies and heat capacities, and a characteristic variation of lateral radial distribution functions, and transverse density profiles across transition regions.

  10. Accelerating Network Traffic Analytics Using Query-DrivenVisualization

    SciTech Connect (OSTI)

    Bethel, E. Wes; Campbell, Scott; Dart, Eli; Stockinger, Kurt; Wu,Kesheng

    2006-07-29T23:59:59.000Z

    Realizing operational analytics solutions where large and complex data must be analyzed in a time-critical fashion entails integrating many different types of technology. This paper focuses on an interdisciplinary combination of scientific data management and visualization/analysis technologies targeted at reducing the time required for data filtering, querying, hypothesis testing and knowledge discovery in the domain of network connection data analysis. We show that use of compressed bitmap indexing can quickly answer queries in an interactive visual data analysis application, and compare its performance with two alternatives for serial and parallel filtering/querying on 2.5 billion records worth of network connection data collected over a period of 42 weeks. Our approach to visual network connection data exploration centers on two primary factors: interactive ad-hoc and multiresolution query formulation and execution over n dimensions and visual display of then-dimensional histogram results. This combination is applied in a case study to detect a distributed network scan and to then identify the set of remote hosts participating in the attack. Our approach is sufficiently general to be applied to a diverse set of data understanding problems as well as used in conjunction with a diverse set of analysis and visualization tools.

  11. An Analysis of Source Tilting and Sub-cell Opacity Sampling for IMC

    SciTech Connect (OSTI)

    Wollaeger, Ryan T. [Los Alamos National Laboratory; Urbatsch, Todd J. [Los Alamos National Laboratory; Wollaber, Allan B. [Los Alamos National Laboratory; Densmore, Jeffery D. [Los Alamos National Laboratory

    2012-08-02T23:59:59.000Z

    Implicit Monte Carlo (IMC) is a stochastic method for solving the radiative transfer equations for multiphysics application with the material in local thermodynamic equilibrium. The IMC method employs a fictitious scattering term that is computed from an implicit discretization of the material temperature equation. Unfortunately, the original histogram representation of the temperature and opacity with respect to the spatial domain leads to nonphysically fast propagation of radiation waves through optically thick material. In the past, heuristic source tilting schemes have been used to mitigate the numerical teleportation error of the radiation particles in IMC that cause this overly rapid radiation wave propagation. While improving the material temperature profile throughout the time duration, these tilting schemes alone do not generally alleviate the teleportation error to suitable levels. Another means of potentially reducing teleportation error in IMC is implementing continuous sub-cell opacities based on sub-cell temperature profiles. We present here an analysis of source tilting and continuous sub-cell opacity sampling applied to various discretizations of the temperature equation. Through this analysis, we demonstrate that applying both heuristics does not necessarily yield more accurate results if the discretization of the material equation is inconsistent with the Monte Carlo sub-cell transport.

  12. Fission signal detection using helium-4 gas fast neutron scintillation detectors

    SciTech Connect (OSTI)

    Lewis, J. M., E-mail: lewisj@ufl.edu; Kelley, R. P.; Jordan, K. A. [Nuclear Engineering Program, University of Florida, Gainesville, Florida 32611 (United States); Murer, D. [Arktis Radiation Detectors Ltd., 8045 Zurich (Switzerland)

    2014-07-07T23:59:59.000Z

    We demonstrate the unambiguous detection of the fission neutron signal produced in natural uranium during active neutron interrogation using a deuterium-deuterium fusion neutron generator and a high pressure {sup 4}He gas fast neutron scintillation detector. The energy deposition by individual neutrons is quantified, and energy discrimination is used to differentiate the induced fission neutrons from the mono-energetic interrogation neutrons. The detector can discriminate between different incident neutron energies using pulse height discrimination of the slow scintillation component of the elastic scattering interaction between a neutron and the {sup 4}He atom. Energy histograms resulting from this data show the buildup of a detected fission neutron signal at higher energies. The detector is shown here to detect a unique fission neutron signal from a natural uranium sample during active interrogation with a (d, d) neutron generator. This signal path has a direct application to the detection of shielded nuclear material in cargo and air containers. It allows for continuous interrogation and detection while greatly minimizing the potential for false alarms.

  13. YT: A Multi-Code Analysis Toolkit for Astrophysical Simulation Data

    SciTech Connect (OSTI)

    Turk, Matthew J.; /San Diego, CASS; Smith, Britton D.; /Michigan State U.; Oishi, Jeffrey S.; /KIPAC, Menlo Park /Stanford U., Phys. Dept.; Skory, Stephen; Skillman, Samuel W.; /Colorado U., CASA; Abel, Tom; /KIPAC, Menlo Park /Stanford U., Phys. Dept.; Norman, Michael L.; /aff San Diego, CASS

    2011-06-23T23:59:59.000Z

    The analysis of complex multiphysics astrophysical simulations presents a unique and rapidly growing set of challenges: reproducibility, parallelization, and vast increases in data size and complexity chief among them. In order to meet these challenges, and in order to open up new avenues for collaboration between users of multiple simulation platforms, we present yt (available at http://yt.enzotools.org/) an open source, community-developed astrophysical analysis and visualization toolkit. Analysis and visualization with yt are oriented around physically relevant quantities rather than quantities native to astrophysical simulation codes. While originally designed for handling Enzo's structure adaptive mesh refinement data, yt has been extended to work with several different simulation methods and simulation codes including Orion, RAMSES, and FLASH. We report on its methods for reading, handling, and visualizing data, including projections, multivariate volume rendering, multi-dimensional histograms, halo finding, light cone generation, and topologically connected isocontour identification. Furthermore, we discuss the underlying algorithms yt uses for processing and visualizing data, and its mechanisms for parallelization of analysis tasks.

  14. Data base for the analysis of compositional characteristics of coal seams and macerals. Final report - Part 10. Variability in the inorganic content of United States' coals: a multivariate statistical study

    SciTech Connect (OSTI)

    Glick, D.C.; Davis, A.

    1984-07-01T23:59:59.000Z

    The multivariate statistical techniques of correlation coefficients, factor analysis, and cluster analysis, implemented by computer programs, can be used to process a large data set and produce a summary of relationships between variables and between samples. These techniques were used to find relationships for data on the inorganic constituents of US coals. Three hundred thirty-five whole-seam channel samples from six US coal provinces were analyzed for inorganic variables. After consideration of the attributes of data expressed on ash basis and whole-coal basis, it was decided to perform complete statistical analyses on both data sets. Thirty variables expressed on whole-coal basis and twenty-six variables expressed on ash basis were used. For each inorganic variable, a frequency distribution histogram and a set of summary statistics was produced. These were subdivided to reveal the manner in which concentrations of inorganic constituents vary between coal provinces and between coal regions. Data collected on 124 samples from three stratigraphic groups (Pottsville, Monongahela, Allegheny) in the Appalachian region were studied using analysis of variance to determine degree of variability between stratigraphic levels. Most variables showed differences in mean values between the three groups. 193 references, 71 figures, 54 tables.

  15. Spatial organization and correlation properties quantify structural changes on mesoscale of parenchymatous plant tissue

    SciTech Connect (OSTI)

    Valous, N. A.; Delgado, A.; Sun, D.-W., E-mail: dawen.sun@ucd.ie [School of Biosystems Engineering, University College Dublin, National University of Ireland, Belfield, Dublin 4, Dublin (Ireland); Drakakis, K. [Complex and Adaptive Systems Laboratory, University College Dublin, National University of Ireland, Belfield, Dublin 4, Dublin (Ireland)

    2014-02-14T23:59:59.000Z

    The study of plant tissue parenchyma's intercellular air spaces contributes to the understanding of anatomy and physiology. This is challenging due to difficulty in making direct measurements of the pore space and the complex mosaic of parenchymatous tissue. The architectural complexity of pore space has shown that single geometrical measurements are not sufficient for characterization. The inhomogeneity of distribution depends not only on the percentage content of phase, but also on how the phase fills the space. The lacunarity morphometric, as multiscale measure, provides information about the distribution of gaps that correspond to degree of spatial organization in parenchyma. Additionally, modern theories have suggested strategies, where the focus has shifted from the study of averages and histograms to the study of patterns in data fluctuations. Detrended fluctuation analysis provides information on the correlation properties of the parenchyma at different spatial scales. The aim is to quantify (with the aid of the aforementioned metrics), the mesostructural changes—that occur from one cycle of freezing and thawing—in the void phase of pome fruit parenchymatous tissue, acquired with X-ray microcomputed tomography. Complex systems methods provide numerical indices and detailed insights regarding the freezing-induced modifications upon the arrangement of cells and voids. These structural changes have the potential to lead to physiological disorders. The work can further stimulate interest for the analysis of internal plant tissue structures coupled with other physico-chemical processes or phenomena.

  16. Population dose commitments due to radioactive releases from nuclear power plant sites in 1983

    SciTech Connect (OSTI)

    Baker, D.A.; Peloquin, R.A.

    1987-04-01T23:59:59.000Z

    Population radiation dose commitments have been estimated from reported radionuclide releases from commercial power reactors operating during 1983. Fifty-year dose commitments from a one-year exposure were calculated from both liquid and atmospheric releases for four population groups (infant, child, teen-ager and adult) residing between 2 and 80 km from each of 52 sites. This report tabulates the results of these calculations, showing the dose commitments for both liquid and airborne pathways for each age group and organ. Also included for each of the sites is a histogram showing the fraction of the total population within 2 to 80 km around each site receiving various average dose commitments from the airborne pathways. The total dose commitments (from both liquid and airborne pathways) for each site ranged from a high of 45 person-rem to a low of 0.002 person-rem for the sites with plants operating throughout the year with an arithmetic mean of 3 person-rem. The total population dose for all sites was estimated at 170 person-rem for the 100 million people considered at risk.

  17. Population dose commitments due to radioactive releases from nuclear power plant sites in 1986

    SciTech Connect (OSTI)

    Baker, D.A. (Pacific Northwest Lab., Richland, WA (USA))

    1989-10-01T23:59:59.000Z

    Population radiation dose commitments have been estimated from reported radionuclide releases from commercial power reactors operating during 1986. Fifty-year dose commitments for a one-year exposure from both liquid and atmospheric releases were calculated for four population groups (infant, child, teen-ager and adult) residing between 2 and 80 km from each of 66 reactor sites. This report tabulates the results of these calculations, showing the dose commitments for both water and airborne pathways for each age group and organ. Also included for each of the sites is a histogram showing the fraction of the total population within 2 to 80 km around each site receiving various average dose commitments from the airborne pathways. The total dose commitments (from both liquid and airborne pathways) for each site ranged from a high of 31 person-rem to a low of 0.0007 person-rem for the sites with plants operating throughout the year with an arithmetic mean of 1.7 person-rem. The total population dose for all sites was estimated at 110 person-rem for the 140 million people considered at risk. The site average individual dose commitment from all pathways ranged from a low of 2 {times} 10{sup -6} mrem to a high of 0.02 mrem. No attempt was made in this study to determine the maximum dose commitment received by any one individual from the radionuclides released at any of the sites. 12 refs.

  18. Population dose commitments due to radioactive releases from nuclear power plant sites in 1984

    SciTech Connect (OSTI)

    Baker, D.A.

    1988-01-01T23:59:59.000Z

    Population radiation dose commitments have been estimated from reported radionuclide releases from commercial power reactors operating during 1984. Fifty-year dose commitments from a one-year exposure were calculated from both liquid and atmospheric releases for four population groups (infant, child, teen-ager and adult) residing between 2 and 80 km from each of 56 sites. This report tabulates the results of these calculations, showing the dose commitments for both liquid and airborne pathways for each age group and organ. Also included for each of the sites is a histogram showing the fraction of the total population within 2 to 80 km around each site receiving various average dose commitments from the airborne pathways. The total dose commitments (from both liquid and airborne pathways) for each site ranged from a high of 110 person-rem to a low of 0.002 person-rem for the sites with plants operating throughout the year with an arithmetic mean of 5 person-rem. The total population dose for all sites was estimated at 280 person-rem for the 100 million people considered at risk. The site average individual dose commitment from all pathways ranged from a low of 6 x 10/sup -6/ mrem to a high of 0.04 mrem. No attempt was made in this study to determine the maximum dose commitment received by any one individual from the radionuclides released at any of the sites.

  19. Population dose commitments due to radioactive releases from nuclear power plant sites in 1987

    SciTech Connect (OSTI)

    Baker, D.A. (Pacific Northwest Lab., Richland, WA (USA))

    1990-08-01T23:59:59.000Z

    Population radiation dose commitments have been estimated from reported radionuclide releases from commercial power reactors operating during 1987. Fifty-year dose commitments for a one-year exposure from both liquid and atmospheric releases were calculated for four population groups (infant, child, teen-ager and adult) residing between 2 and 80 km from each of 70 reactor sites. This report tabulates the results of these calculations, showing the dose commitments for both water and airborne pathways for each age group and organ. Also included for reach of the sites is a histogram showing the fraction of the total population within 2 to 80 km around each site receiving various average dose commitments from the airborne pathways. The site average individual dose commitment from all pathways ranged from a low of 2 {times} 10{sup {minus}6} mrem to a high of 0.009 mrem. No attempt was made in this study to determine the maximum dose commitment received by any one individual from the radionuclides released at any of the sites. However, licensee calculation of doses to the maximally exposed individual at some sites indicated values of up to approximately 100 times average individual doses (on the order of a few millirem per year). 2 refs., 2 figs., 7 tabs.

  20. Regression analysis of WMATA metering information

    SciTech Connect (OSTI)

    Not Available

    1983-12-01T23:59:59.000Z

    The PEPCO provided a magnetic tape that contained energy usage (pulses) data as given in the PEPCO account. The data had 15-min pulses for 26 traction energy meters which were in operation during 1980. The time span was January 20, 1980, to January 19, 1981. Out of 26 traction metering data provided by PEPCO, 18 meters were in DC, 5 meters were in MD, and 3 meters were in VA jurisdictions. The data were converted into Fortran readable form, using program RU0A09.FOR. The system flow chart is shown. Using A, plots were created of summary statistics, which provided through bar charts information on mean, standard deviation, and maximum of power demand. Using B, regression analyses of power vs. car-miles/hour and degree-days for revenue operating and nonoperating periods were established. Using C, energy consumption histograms on each time period for various meters were created. The regression analysis which was done on PEPCO metering data in order to determine the dependence of traction energy usages on car-miles and daily temperature is described in detail.

  1. Conceptual design. Final report: TFE Verification Program

    SciTech Connect (OSTI)

    Not Available

    1994-03-01T23:59:59.000Z

    This report documents the TFE Conceptual Design, which provided the design guidance for the TFE Verification program. The primary goals of this design effort were: (1) establish the conceptual design of an in-core thermionic reactor for a 2 Mw(e) space nuclear power system with a 7-year operating lifetime; (2) demonstrate scalability of the above concept over the output power range of 500 kW(e) to 5 MW(e); and (3) define the TFE which is the basis for the 2 MW (e) reactor design. This TFE specification provided the basis for the test program. These primary goals were achieved. The technical approach taking in the conceptual design effort is discussed in Section 2, and the results are discussed in Section 3. The remainder of this introduction draws a perspective on the role that this conceptual design task played in the TFE Verification Program.

  2. Converter performance TFE Verification Program. Final test report

    SciTech Connect (OSTI)

    Not Available

    1994-03-01T23:59:59.000Z

    This report details TFE Verification Program, the objective, of which is to demonstrate the technology readiness of a TFE suitable for use as the basic element in a thermionic reactor with electric power output in the 0.5 to 5.0 MW(e) range, and a full-power life of 7 years. The TFE Verification Program built directly on the technology and data base developed in the 1960s and early 1970s in an AEC/NASA program, and in the SP-100 program conducted in 1983, 1984 and 1985. In the SP-100 program, the attractive features of thermionic power conversion technology were recognized but concern was expressed over the lack of fast reactor irradiation data. The TFE Verification Program addressed that concern.

  3. Recent Electron-Cloud Simulation Results for the Main Damping Rings of the NLC and the TESLA Linear Colliders

    SciTech Connect (OSTI)

    Pivi, Mauro T F

    2003-05-19T23:59:59.000Z

    In the beam pipe of the Main Damping Ring (MDR) of the Next Linear Collider (NLC), ionization of residual gases and secondary emission give rise to an electron-cloud which stabilizes to equilibrium after few bunch trains. In this paper, we present recent computer simulation results for the main features of the electron cloud at the NLC and preliminary simulation results for the TESLA main damping rings, obtained with the code POSINST that has been developed at LBNL, and lately in collaboration with SLAC, over the past 7 years. Possible remedies to mitigate the effect are also discussed. We have recently included the possibility to simulate different magnetic field configurations in our code including solenoid, quadrupole, sextupole and wiggler.

  4. Effects of a shortened depreciation schedule on the investment costs for combined heat and power

    SciTech Connect (OSTI)

    Kranz, Nicole; Worrell, Ernst

    2001-11-15T23:59:59.000Z

    We investigate and compare several generic depreciation methods to assess the effectiveness of possible policy measures with respect to the depreciation schedules for investments in combined heat and power plants in the United States. We assess the different depreciation methods for CHP projects of various sizes (ranging from 1 MW to 100 MW). We evaluate the impact of different depreciation schedules on the tax shield, and the resulting tax savings to potential investors. We show that a shorter depreciation cycle could have a substantial impact on the cost of producing power, making cogeneration more attractive. The savings amount to approximately 6-7 percent of capital and fixed operation and maintenance costs, when changing from the current system to a 7 year depreciation scheme with switchover from declining balance to straight line depreciation. Suggestions for further research to improve the analysis are given.

  5. A Mushroom-shaped Structure from the Impact of a Cloud with the Galactic Disk

    E-Print Network [OSTI]

    Takahiro Kudoh; Shantanu Basu

    2004-05-08T23:59:59.000Z

    We propose that the mushroom-shaped structure of the Galactic worm GW 123.4--1.5 is created by a cloud collision with the Galactic gas disk. A hydrodynamic simulation shows that a mushroom-shaped structure is created after the cloud crosses the Galactic midplane. The lifetime of the mushroom-shaped structure is of order the dynamical time scale of the disk, \\sim 10^7 years. We find that the velocities across the cap of the mushroom-shaped structure in the simulation are consistent with the observed values. The simulation also predicts a structure on the opposite side of the Galactic plane which is created by the Kelvin-Helmholtz instability after the cloud passes through the disk.

  6. Observational Constraints on Cosmological Models with the Updated Long Gamma-Ray Bursts

    E-Print Network [OSTI]

    Hao Wei

    2010-08-16T23:59:59.000Z

    In the present work, by the help of the newly released Union2 compilation which consists of 557 Type Ia supernovae (SNIa), we calibrate 109 long Gamma-Ray Bursts (GRBs) with the well-known Amati relation, using the cosmology-independent calibration method proposed by Liang {\\it et al.}. We have obtained 59 calibrated high-redshift GRBs which can be used to constrain cosmological models without the circularity problem (we call them ``Hymnium'' GRBs sample for convenience). Then, we consider the joint constraints on 7 cosmological models from the latest observational data, namely, the combination of 557 Union2 SNIa dataset, 59 calibrated Hymnium GRBs dataset (obtained in this work), the shift parameter $R$ from the WMAP 7-year data, and the distance parameter $A$ of the measurement of the baryon acoustic oscillation (BAO) peak in the distribution of SDSS luminous red galaxies. We also briefly consider the comparison of these 7 cosmological models.

  7. Testing a DBI model for the unification of dark matter and dark energy with Gamma-Ray Bursts

    E-Print Network [OSTI]

    Ariadna Montiel; Nora Bretón

    2012-02-14T23:59:59.000Z

    We study the range of consistency of a model based on a nonlinear scalar field Dirac-Born-Infeld action for the unification of dark matter and dark energy using Gamma-Ray Bursts at high-redshifts. We use the sample of 59 high-redshift GRBs reported by Wei (2010), calibrated at low redshifts with the Union 2 sample of SNe Ia, thus avoiding the circularity problem. In this analysis, we also include the CMB7-year data and the baryonic acoustic peak BAO. Besides, it is calculated the parameter of the equation of state $w$, the deceleration parameter $q_0$ and the redshift of the transition to the decelerate-accelerated phase $z_t$.

  8. Kern River natural gas pipeline commissioned

    SciTech Connect (OSTI)

    Not Available

    1992-03-16T23:59:59.000Z

    Kern River Gas Transmission Co., the biggest gas pipeline built in the U.S. in the last decade, has been commissioned. The system was dedicated Mar. 6 at a meter station in an oil field near Bakersfield, Calif. The $984 million, 904 mile pipeline is a 50-50 venture of Tenneco Inc. and Williams Cos. Planning for the project began about 7 years ago. Current operating capacity of the line is 700 MMcfd. Plans call for boosting capacity by 452 MMcfd with added compression. Most of the gas will go to thermal enhanced oil recovery projects in heavy oil fields in California. This paper reports that other customers include utilities, independent electrical power producers, and cogeneration projects.

  9. PanDA Beyond ATLAS: Workload Management for Data Intensive Science

    E-Print Network [OSTI]

    Schovancova, J; The ATLAS collaboration; Klimentov, A; Maeno, T; Nilsson, P; Oleynik, D; Panitkin, S; Petrosyan, A; Vaniachine, A; Wenaus, T; Yu, D

    2013-01-01T23:59:59.000Z

    The PanDA Production ANd Distributed Analysis system has been developed by ATLAS to meet the experiment's requirements for a data-driven workload management system for production and distributed analysis processing capable of operating at LHC data processing scale. After 7 years of impressively successful PanDA operation in ATLAS there are also other experiments which can benefit from PanDA in the Big Data challenge, with several at various stages of evaluation and adoption. The new project "Next Generation Workload Management and Analysis System for Big Data" is extending PanDA to meet the needs of other data intensive scientific applications in HEP, astro-particle and astrophysics communities, bio-informatics and other fields as a general solution to large scale workload management. PanDA can utilize dedicated or opportunistic computing resources such as grids, clouds, and High Performance Computing facilities, and is being extended to leverage next generation intelligent networks in automated workflow mana...

  10. Optical and radio variability of the BL Lac object AO 0235+16: a possible 5-6 year periodicity

    E-Print Network [OSTI]

    C. M. Raiteri; M. Villata; H. D. Aller; M. F. Aller; J. Heidt; O. M. Kurtanidze; L. Lanteri; M. Maesano; E. Massaro; F. Montagni; R. Nesci; K. Nilsson; M. G. Nikolashvili; P. Nurmi; L. Ostorero; T. Pursimo; R. Rekola; A. Sillanpaa; L. O. Takalo; H. Terasranta; G. Tosti; T. J. Balonek; M. Feldt; E. J. McGrath; A. Heines; C. Heisler; J. Hu; M. Kidger; J. R. Mattox; A. Pati; R. Robb; A. C. Sadun; P. Shastri; S. J. Wagner; J. Wei; X. Wu

    2001-08-09T23:59:59.000Z

    New optical and radio data on the BL Lacertae object AO 0235+16 have been collected in the last four years by a wide international collaboration, which confirm the intense activity of this source. The optical data also include the results of the Whole Earth Blazar Telescope (WEBT) first-light campaign organized in November 1997. The optical spectrum is observed to basically steepen when the source gets fainter. We have investigated the existence of typical variability time scales and of possible correlations between the optical and radio emissions by means of visual inspection, Discrete Correlation Function analysis, and Discrete Fourier Transform technique. The major radio outbursts are found to repeat quasi-regularly with a periodicity of about 5.7 years; this period is also in agreement with the occurrence of some of the major optical outbursts, but not all of them.

  11. Pierre Auger Results

    SciTech Connect (OSTI)

    Chou, Aaron

    2008-01-14T23:59:59.000Z

    Using data collected at the Pierre Auger Observatory during the past 3.7 years, we demonstrate that there is a correlation between the arrival directions of cosmic rays with energy above 6 [1] 1019 eV and the positions of active galactic nuclei (AGN) lying within 75 Mpc. We reject the hypothesis of an isotropic distribution of these cosmic rays at over 99% confidence level from a prescribed a priori test. The correlation we observe is compatible with the hypothesis that the highest energy particles originate from relatively nearby extragalactic sources whose fluxes have therefore not been significantly reduced by interaction with the cosmic background radiation. AGN or objects having a similar spatial distribution are possible sources.

  12. Running-mass inflation model and primordial black holes

    SciTech Connect (OSTI)

    Drees, Manuel; Erfani, Encieh, E-mail: drees@th.physik.uni-bonn.de, E-mail: erfani@th.physik.uni-bonn.de [Physikalisches Institut and Bethe Center for Theoretical Physics, Universität Bonn, Nussallee 12, 53115 Bonn (Germany)

    2011-04-01T23:59:59.000Z

    We revisit the question whether the running-mass inflation model allows the formation of Primordial Black Holes (PBHs) that are sufficiently long-lived to serve as candidates for Dark Matter. We incorporate recent cosmological data, including the WMAP 7-year results. Moreover, we include ''the running of the running'' of the spectral index of the power spectrum, as well as the renormalization group ''running of the running'' of the inflaton mass term. Our analysis indicates that formation of sufficiently heavy, and hence long-lived, PBHs still remains possible in this scenario. As a by-product, we show that the additional term in the inflaton potential still does not allow significant negative running of the spectral index.

  13. An economic analysis of conservation and management measures carried out on the Blacklands Experimental Watershed, Riesel, Texas

    E-Print Network [OSTI]

    Decker, Robert David

    1958-01-01T23:59:59.000Z

    .5 705 1952 47.2 56.6 2672 35.5 52.0 1846 1953 53.7 60.1 3227 41.6 63.2 2629 1954 57.5 43.8 2519 36.5 31.0 1132 1955 32.0 1885 48.1 30.9 U86 Total 351.0 13847 256.4 9540 7 year weighted avg.39.45 37.21 Difference 2.24 22 LlBP A,?:'v : Jt * CUL i... ON-4- ON {H 03 3o o?H -P0} ? & ON C"? cv ?H O C- ? 2G O' ON ? rV ?*4ON 2G 8 ? O rV OON UA C \\^ CV v...

  14. Haloarchaeal Protein Translocation via the Twin Arginine Translocation Pathway

    SciTech Connect (OSTI)

    Pohlschroder Mechthild

    2009-02-03T23:59:59.000Z

    Protein transport across hydrophobic membranes that partition cellular compartments is essential in all cells. The twin arginine translocation (Tat) pathway transports proteins across the prokaryotic cytoplasmic membranes. Distinct from the universally conserved Sec pathway, which secretes unfolded proteins, the Tat machinery is unique in that it secretes proteins in a folded conformation, making it an attractive pathway for the transport and secretion of heterologously expressed proteins that are Sec-incompatible. During the past 7 years, the DOE-supported project has focused on the characterization of the diversity of bacterial and archaeal Tat substrates as well as on the characterization of the Tat pathway of a model archaeon, Haloferax volcanii, a member of the haloarchaea. We have demonstrated that H. volcanii uses this pathway to transport most of its secretome.

  15. Destruction of protoplanetary disks in the Orion Nebula Cluster

    E-Print Network [OSTI]

    Aylwyn Scally; Cathie Clarke

    2000-12-05T23:59:59.000Z

    We use numerical N-body simulations of the Orion Nebula Cluster (ONC) to investigate the destruction of protoplanetary disks by close stellar encounters and UV radiation from massive stars. The simulations model a cluster of 4000 stars, and we consider separately cases in which the disks have fixed radii of 100 AU and 10 AU. In the former case, depending on a star's position and orbit in the cluster over 10^7 years, UV photoevaporation removes at least 0.01 Msol from its disk, and can remove up to 1 Msol. We find no dynamical models of the ONC consistent with the suggestion of Storzer and Hollenbach that the observed distribution and abundance of proplyds could be explained by a population of stars on radial orbits which spend relatively little time near Theta 1C Ori (the most massive star in the ONC). Instead the observations require either massive disks (e.g. a typical initial disk mass of 0.4 Msol) or a very recent birth for Theta 1C Ori. When we consider the photoevaporation of the inner 10 AU of disks in the ONC, we find that planet formation would be hardly affected. Outside that region, planets would be prevented from forming in about half the systems, unless either the initial disk masses were very high or they formed in less than ~ 2 Myr and Theta 1C Ori has only very recently appeared. We also present statistics on the distribution of minimum stellar encounter separations. This peaks at 1000 AU, with less than 10% of stars having had an encounter closer than 100 AU after 10^7 years. We conclude that stellar encounters are unlikely to play a significant role in destroying protoplanetary disks. In the absence of any disruption mechanism other than those considered here, we would thus predict planetary systems like our own to be common amongst stars forming in ONC-like environments.

  16. United Kingdom Carotid Artery Stent Registry: Short- and Long-Term Outcomes

    SciTech Connect (OSTI)

    Goode, S. D., E-mail: s.goode@sheffield.ac.uk; Cleveland, T. J.; Gaines, P. A. [Northern General Hospital, Sheffield Vascular Institute (United Kingdom)] [Northern General Hospital, Sheffield Vascular Institute (United Kingdom)

    2013-10-15T23:59:59.000Z

    Background: Carotid artery stenting (CAS) has evolved to treat carotid artery disease with the intention of prevent stroke. The British Society of Interventional Radiologists developed a voluntary registry to monitor the practice of this novel procedure. We present the data from the United Kingdom (UK) CAS registry for short and long-term outcomes for symptomatic and asymptomatic carotid disease. Methods: The UK CAS registry collected data from 1998 to 2010 from 31 hospitals across the UK for 1,154 patients. All interventions were enrolled in the registry for both asymptomatic and symptomatic patients. Initial entry forms were completed for each patient entered with data including indications, demographic data, CAS data (including stents and protection device details) and 30-day outcomes. Complications were documented. Follow-up data were collected at yearly intervals. Results: Nine hundred fifty-three (83 %) symptomatic and 201 (17 %) asymptomatic patients were enrolled into the registry. The 30-day all stroke and death rates for symptomatic patients were 5.5 and 2.2 % for those with asymptomatic disease. The 30-day mortality rate was 1.7 % for symptomatic and 0.6 % for asymptomatic patients. For symptomatic patients undergoing CAS, the 7-year all-cause mortality rate was 22.2 % and for asymptomatic patients 18.1 %. The 7-year all-cause mortality and disabling stroke rates were 25.3 and 19.4 %, respectively. Conclusion: These data indicate that outside of the tight constraints of a randomised trial, CAS provides effective prophylaxis against stroke and death.

  17. Longitudinal changes in PON1 enzymatic activities in Mexican-American mothers and children with different genotypes and haplotypes

    SciTech Connect (OSTI)

    Huen, Karen; Harley, Kim; Bradman, Asa; Eskenazi, Brenda [Center for Children's Environmental Health, 50 University Hall, School of Public Health, University of California, Berkeley, CA 94720-7360 (United States); Holland, Nina, E-mail: ninah@berkeley.ed [Center for Children's Environmental Health, 50 University Hall, School of Public Health, University of California, Berkeley, CA 94720-7360 (United States)

    2010-04-15T23:59:59.000Z

    The paraoxonase 1 (PON1) enzyme prevents low-density lipoprotein oxidation and also detoxifies the oxon derivatives of certain neurotoxic organophosphate (OP) pesticides. PON1 activity in infants is low compared to adults, rendering them with lower metabolic and antioxidant capacities. We made a longitudinal comparison of the role of genetic variability on control of PON1 phenotypes in Mexican-American mothers and their children at the time of delivery (n = 388 and 338, respectively) and again 7 years later (n = 280 and 281, respectively) using generalized estimating equations models. At age 7, children's mean PON1 activities were still lower than those of mothers. This difference was larger in children with genotypes associated with low PON1 activities (PON1{sub -108TT}, PON1{sub 192QQ}, and PON1{sub -909CC}). In mothers, PON1 activities were elevated at delivery and during pregnancy compared to 7 years later when they were not pregnant (p < 0.001). In non-pregnant mothers, PON1 polymorphisms and haplotypes accounted for almost 2-fold more variation of arylesterase (AREase) and chlorpyrifos-oxonase (CPOase) activity than in mothers at delivery. In both mothers and children, the five PON1 polymorphisms (192, 55, -108, -909, -162) explained a noticeably larger proportion of variance of paraoxonase activity (62-78%) than AREase activity (12.3-26.6%). Genetic control of PON1 enzymatic activity varies in children compared to adults and is also affected by pregnancy status. In addition to known PON1 polymorphisms, unidentified environmental, genetic, or epigenetic factors may also influence variability of PON1 expression and therefore susceptibility to OPs and oxidative stress.

  18. Assessment of Energy Production Potential from Ocean Currents along the United States Coastline

    SciTech Connect (OSTI)

    Haas, Kevin

    2013-09-15T23:59:59.000Z

    Increasing energy consumption and depleting reserves of fossil fuels have resulted in growing interest in alternative renewable energy from the ocean. Ocean currents are an alternative source of clean energy due to their inherent reliability, persistence and sustainability. General ocean circulations exist in the form of large rotating ocean gyres, and feature extremely rapid current flow in the western boundaries due to the Coriolis Effect. The Gulf Stream system is formed by the western boundary current of the North Atlantic Ocean that flows along the east coastline of the United States, and therefore is of particular interest as a potential energy resource for the United States. This project created a national database of ocean current energy resources to help advance awareness and market penetration in ocean current energy resource assessment. The database, consisting of joint velocity magnitude and direction probability histograms, was created from data created by seven years of numerical model simulations. The accuracy of the database was evaluated by ORNL?s independent validation effort documented in a separate report. Estimates of the total theoretical power resource contained in the ocean currents were calculated utilizing two separate approaches. Firstly, the theoretical energy balance in the Gulf Stream system was examined using the two-dimensional ocean circulation equations based on the assumptions of the Stommel model for subtropical gyres with the quasi-geostrophic balance between pressure gradient, Coriolis force, wind stress and friction driving the circulation. Parameters including water depth, natural dissipation rate and wind stress are calibrated in the model so that the model can reproduce reasonable flow properties including volume flux and energy flux. To represent flow dissipation due to turbines additional turbine drag coefficient is formulated and included in the model. Secondly, to determine the reasonableness of the total power estimates from the Stommel model and to help determine the size and capacity of arrays necessary to extract the maximum theoretical power, further estimates of the available power based on the distribution of the kinetic power density in the undisturbed flow was completed. This used estimates of the device spacing and scaling to sum up the total power that the devices would produce. The analysis has shown that considering extraction over a region comprised of the Florida Current portion of the Gulf Stream system, the average power dissipated ranges between 4-6 GW with a mean around 5.1 GW. This corresponds to an average of approximately 45 TWh/yr. However, if the extraction area comprises the entire portion of the Gulf Stream within 200 miles of the US coastline from Florida to North Carolina, the average power dissipated becomes 18.6 GW or 163 TWh/yr. A web based GIS interface, http://www.oceancurrentpower.gatech.edu/, was developed for dissemination of the data. The website includes GIS layers of monthly and yearly mean ocean current velocity and power density for ocean currents along the entire coastline of the United States, as well as joint and marginal probability histograms for current velocities at a horizontal resolution of 4-7 km with 10-25 bins over depth. Various tools are provided for viewing, identifying, filtering and downloading the data.

  19. Modeling the dosimetry of organ-at-risk in head and neck IMRT planning: An intertechnique and interinstitutional study

    SciTech Connect (OSTI)

    Lian, Jun, E-mail: jun-lian@med.unc.edu; Chera, Bhishamjit S.; Chang, Sha [Department of Radiation Oncology, The University of North Carolina, Chapel Hill, North Carolina 27599 (United States)] [Department of Radiation Oncology, The University of North Carolina, Chapel Hill, North Carolina 27599 (United States); Yuan, Lulin, E-mail: lulin.yuan@duke.edu; Yoo, David P.; Yin, FangFang; Wu, Q. Jackie, E-mail: jackie.wu@duke.edu [Department of Radiation Oncology, Duke University, Durham, North Carolina 27710 (United States); Ge, Yaorong [Department of Software and Information Systems, The University of North Carolina, Charlotte, North Carolina 28223 (United States)] [Department of Software and Information Systems, The University of North Carolina, Charlotte, North Carolina 28223 (United States)

    2013-12-15T23:59:59.000Z

    Purpose: To build a statistical model to quantitatively correlate the anatomic features of structures and the corresponding dose-volume histogram (DVH) of head and neck (HN) Tomotherapy (Tomo) plans. To study if the model built upon one intensity modulated radiation therapy (IMRT) technique (such as conventional Linac) can be used to predict anticipated organs-at-risk (OAR) DVH of patients treated with a different IMRT technique (such as Tomo). To study if the model built upon the clinical experience of one institution can be used to aid IMRT planning for another institution. Methods: Forty-four Tomotherapy intensity modulate radiotherapy plans of HN cases (Tomo-IMRT) from Institution A were included in the study. A different patient group of 53 HN fixed gantry IMRT (FG-IMRT) plans was selected from Institution B. The analyzed OARs included the parotid, larynx, spinal cord, brainstem, and submandibular gland. Two major groups of anatomical features were considered: the volumetric information and the spatial information. The volume information includes the volume of target, OAR, and overlapped volume between target and OAR. The spatial information of OARs relative to PTVs was represented by the distance-to-target histogram (DTH). Important anatomical and dosimetric features were extracted from DTH and DVH by principal component analysis. Two regression models, one for Tomotherapy plan and one for IMRT plan, were built independently. The accuracy of intratreatment-modality model prediction was validated by a leave one out cross-validation method. The intertechnique and interinstitution validations were performed by using the FG-IMRT model to predict the OAR dosimetry of Tomo-IMRT plans. The dosimetry of OARs, under the same and different institutional preferences, was analyzed to examine the correlation between the model prediction and planning protocol. Results: Significant patient anatomical factors contributing to OAR dose sparing in HN Tomotherapy plans have been analyzed and identified. For all the OARs, the discrepancies of dose indices between the model predicted values and the actual plan values were within 2.1%. Similar results were obtained from the modeling of FG-IMRT plans. The parotid gland was spared in a comparable fashion during the treatment planning of two institutions. The model based on FG-IMRT plans was found to predict the median dose of the parotid of Tomotherapy plans quite well, with a mean error of 2.6%. Predictions from the FG-IMRT model suggested the median dose of the larynx, median dose of the brainstem and D2 of the brainstem could be reduced by 10.5%, 12.8%, and 20.4%, respectively, in the Tomo-IMRT plans. This was found to be correlated to the institutional differences in OAR constraint settings. Re-planning of six Tomotherapy patients confirmed the potential of optimization improvement predicted by the FG-IMRT model was correct. Conclusions: The authors established a mathematical model to correlate the anatomical features and dosimetric indexes of OARs of HN patients in Tomotherapy plans. The model can be used for the setup of patient-specific OAR dose sparing goals and quality control of planning results. The institutional clinical experience was incorporated into the model which allows the model from one institution to generate a reference plan for another institution, or another IMRT technique.

  20. Quantitative assessment of the accuracy of dose calculation using pencil beam and Monte Carlo algorithms and requirements for clinical quality assurance

    SciTech Connect (OSTI)

    Ali, Imad, E-mail: iali@ouhsc.edu [Department of Radiation Oncology, University of Oklahoma Health Sciences Center, Oklahoma City, OK (United States); Ahmad, Salahuddin [Department of Radiation Oncology, University of Oklahoma Health Sciences Center, Oklahoma City, OK (United States)

    2013-10-01T23:59:59.000Z

    To compare the doses calculated using the BrainLAB pencil beam (PB) and Monte Carlo (MC) algorithms for tumors located in various sites including the lung and evaluate quality assurance procedures required for the verification of the accuracy of dose calculation. The dose-calculation accuracy of PB and MC was also assessed quantitatively with measurement using ionization chamber and Gafchromic films placed in solid water and heterogeneous phantoms. The dose was calculated using PB convolution and MC algorithms in the iPlan treatment planning system from BrainLAB. The dose calculation was performed on the patient's computed tomography images with lesions in various treatment sites including 5 lungs, 5 prostates, 4 brains, 2 head and necks, and 2 paraspinal tissues. A combination of conventional, conformal, and intensity-modulated radiation therapy plans was used in dose calculation. The leaf sequence from intensity-modulated radiation therapy plans or beam shapes from conformal plans and monitor units and other planning parameters calculated by the PB were identical for calculating dose with MC. Heterogeneity correction was considered in both PB and MC dose calculations. Dose-volume parameters such as V95 (volume covered by 95% of prescription dose), dose distributions, and gamma analysis were used to evaluate the calculated dose by PB and MC. The measured doses by ionization chamber and EBT GAFCHROMIC film in solid water and heterogeneous phantoms were used to quantitatively asses the accuracy of dose calculated by PB and MC. The dose-volume histograms and dose distributions calculated by PB and MC in the brain, prostate, paraspinal, and head and neck were in good agreement with one another (within 5%) and provided acceptable planning target volume coverage. However, dose distributions of the patients with lung cancer had large discrepancies. For a plan optimized with PB, the dose coverage was shown as clinically acceptable, whereas in reality, the MC showed a systematic lack of dose coverage. The dose calculated by PB for lung tumors was overestimated by up to 40%. An interesting feature that was observed is that despite large discrepancies in dose-volume histogram coverage of the planning target volume between PB and MC, the point doses at the isocenter (center of the lesions) calculated by both algorithms were within 7% even for lung cases. The dose distributions measured with EBT GAFCHROMIC films in heterogeneous phantoms showed large discrepancies of nearly 15% lower than PB at interfaces between heterogeneous media, where these lower doses measured by the film were in agreement with those by MC. The doses (V95) calculated by MC and PB agreed within 5% for treatment sites with small tissue heterogeneities such as the prostate, brain, head and neck, and paraspinal tumors. Considerable discrepancies, up to 40%, were observed in the dose-volume coverage between MC and PB in lung tumors, which may affect clinical outcomes. The discrepancies between MC and PB increased for 15 MV compared with 6 MV indicating the importance of implementation of accurate clinical treatment planning such as MC. The comparison of point doses is not representative of the discrepancies in dose coverage and might be misleading in evaluating the accuracy of dose calculation between PB and MC. Thus, the clinical quality assurance procedures required to verify the accuracy of dose calculation using PB and MC need to consider measurements of 2- and 3-dimensional dose distributions rather than a single point measurement using heterogeneous phantoms instead of homogenous water-equivalent phantoms.

  1. Respiratory Organ Motion and Dosimetric Impact on Breast and Nodal Irradiation

    SciTech Connect (OSTI)

    Qi, X. Sharon, E-mail: xiangrong.qi@ucdenver.ed [Department of Radiation Oncology, University of Colorado Denver, Aurora, CO (United States); White, Julia [Department of Radiation Oncology, Medical College of Wisconsin, Milwaukee, WI (United States); Rabinovitch, Rachel [Department of Radiation Oncology, University of Colorado Denver, Aurora, CO (United States); Merrell, Kenneth; Sood, Amit; Bauer, Anderson; Wilson, J. Frank [Department of Radiation Oncology, Medical College of Wisconsin, Milwaukee, WI (United States); Miften, Moyed [Department of Radiation Oncology, University of Colorado Denver, Aurora, CO (United States); Li, X. Allen [Department of Radiation Oncology, Medical College of Wisconsin, Milwaukee, WI (United States)

    2010-10-01T23:59:59.000Z

    Purpose: To examine the respiratory motion for target and normal structures during whole breast and nodal irradiation and the resulting dosimetric impact. Methods and Materials: Four-dimensional CT data sets of 18 patients with early-stage breast cancer were analyzed retrospectively. A three-dimensional conformal dosimetric plan designed to irradiate the breast was generated on the basis of CT images at 20% respiratory phase (reference phase). The reference plans were copied to other respiratory phases at 0% (end of inspiration) and 50% (end of expiration) to simulate the effects of breathing motion on whole breast irradiation. Dose-volume histograms, equivalent uniform dose, and normal tissue complication probability were evaluated and compared. Results: Organ motion of up to 8.8 mm was observed during free breathing. A large lung centroid movement was typically associated with a large shift of other organs. The variation of planning target volume coverage during a free breathing cycle is generally within 1%-5% (17 of 18 patients) compared with the reference plan. However, up to 28% of V{sub 45} variation for the internal mammary nodes was observed. Interphase mean dose variations of 2.2%, 1.2%, and 1.4% were observed for planning target volume, ipsilateral lung, and heart, respectively. Dose variations for the axillary nodes and brachial plexus were minimal. Conclusions: The doses delivered to the target and normal structures are different from the planned dose based on the reference phase. During normal breathing, the dosimetric impact of respiratory motion is clinically insignificant with the exception of internal mammary nodes. However, noticeable degradation in dosimetric plan quality may be expected for the patients with large respiratory motion.

  2. Dosimetric accuracy of a deterministic radiation transport based {sup 192}Ir brachytherapy treatment planning system. Part III. Comparison to Monte Carlo simulation in voxelized anatomical computational models

    SciTech Connect (OSTI)

    Zourari, K.; Pantelis, E.; Moutsatsos, A.; Sakelliou, L.; Georgiou, E.; Karaiskos, P.; Papagiannis, P. [Medical Physics Laboratory, Medical School, University of Athens, 75 Mikras Asias, 115 27 Athens (Greece); Department of Physics, Nuclear and Particle Physics Section, University of Athens, Ilisia, 157 71 Athens (Greece); Medical Physics Laboratory, Medical School, University of Athens, 75 Mikras Asias, 115 27 Athens (Greece)

    2013-01-15T23:59:59.000Z

    Purpose: To compare TG43-based and Acuros deterministic radiation transport-based calculations of the BrachyVision treatment planning system (TPS) with corresponding Monte Carlo (MC) simulation results in heterogeneous patient geometries, in order to validate Acuros and quantify the accuracy improvement it marks relative to TG43. Methods: Dosimetric comparisons in the form of isodose lines, percentage dose difference maps, and dose volume histogram results were performed for two voxelized mathematical models resembling an esophageal and a breast brachytherapy patient, as well as an actual breast brachytherapy patient model. The mathematical models were converted to digital imaging and communications in medicine (DICOM) image series for input to the TPS. The MCNP5 v.1.40 general-purpose simulation code input files for each model were prepared using information derived from the corresponding DICOM RT exports from the TPS. Results: Comparisons of MC and TG43 results in all models showed significant differences, as reported previously in the literature and expected from the inability of the TG43 based algorithm to account for heterogeneities and model specific scatter conditions. A close agreement was observed between MC and Acuros results in all models except for a limited number of points that lay in the penumbra of perfectly shaped structures in the esophageal model, or at distances very close to the catheters in all models. Conclusions: Acuros marks a significant dosimetry improvement relative to TG43. The assessment of the clinical significance of this accuracy improvement requires further work. Mathematical patient equivalent models and models prepared from actual patient CT series are useful complementary tools in the methodology outlined in this series of works for the benchmarking of any advanced dose calculation algorithm beyond TG43.

  3. Improvement of dose distribution in breast radiotherapy using a reversible transverse magnetic field Linac-MR unit

    SciTech Connect (OSTI)

    Esmaeeli, A. D., E-mail: ali-esmaeeli-d@yahoo.com [Department of Physics, Rasht Branch, Islamic Azad University, Rasht, 41476-54919 (Iran, Islamic Republic of); Mahdavi, S. R. [Department of Medical Physics, Tehran University of Medical Sciences, Tehran, 14174 (Iran, Islamic Republic of)] [Department of Medical Physics, Tehran University of Medical Sciences, Tehran, 14174 (Iran, Islamic Republic of); Pouladian, M.; Bagheri, S. [Department of Medical Radiation Engineering, Science and Research Branch, Islamic Azad University, Tehran, 14778-93855 (Iran, Islamic Republic of)] [Department of Medical Radiation Engineering, Science and Research Branch, Islamic Azad University, Tehran, 14778-93855 (Iran, Islamic Republic of); Monfared, A. S. [Department of Medical Physics, Babol University of Medical Sciences, Babol, 47148-71167 (Iran, Islamic Republic of)] [Department of Medical Physics, Babol University of Medical Sciences, Babol, 47148-71167 (Iran, Islamic Republic of)

    2014-01-15T23:59:59.000Z

    Purpose: To investigate the improvement in dose distribution in tangential breast radiotherapy using a reversible transverse magnetic field that maintains the same direction of Lorentz force between two fields. The investigation has a potential application in future Linac-MR units. Methods: Computed tomography images of four patients and magnetic fields of 0.25–1.5 Tesla (T) were used for Monte Carlo simulation. Two patients had intact breast while the other two had mastectomy. Simulations of planning and chest wall irradiation were similar to the actual clinical process. The direction of superior-inferior magnetic field for the medial treatment beam was reversed for the lateral beam. Results: For the ipsilateral lung and heart mean doses were reduced by a mean (range) of 45.8% (27.6%–58.6%) and 26.0% (20.2%–38.9%), respectively, depending on various treatment plan setups. The mean V{sub 20} for ipsilateral lung was reduced by 55.0% (43.6%–77.3%). In addition acceptable results were shown after simulation of 0.25 T magnetic field demonstrated in dose-volume reductions of the heart, ipsilateral lung, and noninvolved skin. Conclusions: Applying a reversible magnetic field during breast radiotherapy, not only reduces the dose to the lung and heart but also produces a sharp drop dose volume histogram for planning target volume, because of bending of the path of secondary charged particles toward the chest wall by the Lorentz force. The simulations have shown that use of the magnetic field at 1.5 T is not feasible for clinical applications due to the increase of ipsilateral chest wall skin dose in comparison to the conventional planning while 0.25 T is suitable for all patients due to dose reduction to the chest wall skin.

  4. Low-frequency quantitative ultrasound imaging of cell death in vivo

    SciTech Connect (OSTI)

    Sadeghi-Naini, Ali; Falou, Omar; Czarnota, Gregory J. [Imaging Research – Physical Science, Sunnybrook Research Institute, Sunnybrook Health Sciences Centre, Toronto, Ontario M4N 3M5 (Canada) [Imaging Research – Physical Science, Sunnybrook Research Institute, Sunnybrook Health Sciences Centre, Toronto, Ontario M4N 3M5 (Canada); Department of Radiation Oncology, Odette Cancer Centre, Sunnybrook Health Sciences Centre, Toronto, Ontario M4N 3M5 (Canada); Department of Medical Biophysics, Faculty of Medicine, University of Toronto, Toronto, Ontario M4N 3M5 (Canada); Department of Radiation Oncology, Faculty of Medicine, University of Toronto, Toronto, Ontario M4N 3M5 (Canada); Papanicolau, Naum; Tadayyon, Hadi [Imaging Research – Physical Science, Sunnybrook Research Institute, Sunnybrook Health Sciences Centre, Toronto, Ontario M4N 3M5, Canada and Department of Medical Biophysics, Faculty of Medicine, University of Toronto, Toronto, Ontario M4N 3M5 (Canada)] [Imaging Research – Physical Science, Sunnybrook Research Institute, Sunnybrook Health Sciences Centre, Toronto, Ontario M4N 3M5, Canada and Department of Medical Biophysics, Faculty of Medicine, University of Toronto, Toronto, Ontario M4N 3M5 (Canada); Lee, Justin [Department of Radiation Oncology, Odette Cancer Centre, Sunnybrook Health Sciences Centre, Toronto, Ontario M4N 3M5, Canada and Department of Radiation Oncology, Faculty of Medicine, University of Toronto, Toronto, Ontario M4N 3M5 (Canada)] [Department of Radiation Oncology, Odette Cancer Centre, Sunnybrook Health Sciences Centre, Toronto, Ontario M4N 3M5, Canada and Department of Radiation Oncology, Faculty of Medicine, University of Toronto, Toronto, Ontario M4N 3M5 (Canada); Zubovits, Judit [Department of Pathology, Sunnybrook Health Sciences Centre, Toronto, Ontario M4N 3M5 (Canada)] [Department of Pathology, Sunnybrook Health Sciences Centre, Toronto, Ontario M4N 3M5 (Canada); Sadeghian, Alireza [Department of Computer Science, Ryerson University, Toronto, Ontario M5B 2K3 (Canada)] [Department of Computer Science, Ryerson University, Toronto, Ontario M5B 2K3 (Canada); Karshafian, Raffi [Department of Physics, Ryerson University, Toronto, Ontario M5B 2K3 (Canada)] [Department of Physics, Ryerson University, Toronto, Ontario M5B 2K3 (Canada); Al-Mahrouki, Azza; Giles, Anoja [Imaging Research – Physical Science, Sunnybrook Research Institute, Sunnybrook Health Sciences Centre, Toronto, Ontario M4N 3M5, Canada and Department of Radiation Oncology, Odette Cancer Centre, Sunnybrook Health Sciences Centre, Toronto, Ontario M4N 3M5 (Canada)] [Imaging Research – Physical Science, Sunnybrook Research Institute, Sunnybrook Health Sciences Centre, Toronto, Ontario M4N 3M5, Canada and Department of Radiation Oncology, Odette Cancer Centre, Sunnybrook Health Sciences Centre, Toronto, Ontario M4N 3M5 (Canada); Kolios, Michael C. [Department of Medical Biophysics, Faculty of Medicine, University of Toronto, Toronto, Ontario M4N 3M5, Canada and Department of Physics, Ryerson University, Toronto, Ontario M5B 2K3 (Canada)] [Department of Medical Biophysics, Faculty of Medicine, University of Toronto, Toronto, Ontario M4N 3M5, Canada and Department of Physics, Ryerson University, Toronto, Ontario M5B 2K3 (Canada)

    2013-08-15T23:59:59.000Z

    Purpose: Currently, no clinical imaging modality is used routinely to assess tumor response to cancer therapies within hours to days of the delivery of treatment. Here, the authors demonstrate the efficacy of ultrasound at a clinically relevant frequency to quantitatively detect changes in tumors in response to cancer therapies using preclinical mouse models.Methods: Conventional low-frequency and corresponding high-frequency ultrasound (ranging from 4 to 28 MHz) were used along with quantitative spectroscopic and signal envelope statistical analyses on data obtained from xenograft tumors treated with chemotherapy, x-ray radiation, as well as a novel vascular targeting microbubble therapy.Results: Ultrasound-based spectroscopic biomarkers indicated significant changes in cell-death associated parameters in responsive tumors. Specifically changes in the midband fit, spectral slope, and 0-MHz intercept biomarkers were investigated for different types of treatment and demonstrated cell-death related changes. The midband fit and 0-MHz intercept biomarker derived from low-frequency data demonstrated increases ranging approximately from 0 to 6 dBr and 0 to 8 dBr, respectively, depending on treatments administrated. These data paralleled results observed for high-frequency ultrasound data. Statistical analysis of ultrasound signal envelope was performed as an alternative method to obtain histogram-based biomarkers and provided confirmatory results. Histological analysis of tumor specimens indicated up to 61% cell death present in the tumors depending on treatments administered, consistent with quantitative ultrasound findings indicating cell death. Ultrasound-based spectroscopic biomarkers demonstrated a good correlation with histological morphological findings indicative of cell death (r{sup 2}= 0.71, 0.82; p < 0.001).Conclusions: In summary, the results provide preclinical evidence, for the first time, that quantitative ultrasound used at a clinically relevant frequency, in addition to high-frequency ultrasound, can detect tissue changes associated with cell death in vivo in response to cancer treatments.

  5. Investigation of Pitch and Jaw Width to Decrease Delivery Time of Helical Tomotherapy Treatments for Head and Neck Cancer

    SciTech Connect (OSTI)

    Moldovan, Monica [Mary Bird Perkins Cancer Center, Baton Rouge, LA (United States); Fontenot, Jonas D., E-mail: jfontenot@marybird.com [Mary Bird Perkins Cancer Center, Baton Rouge, LA (United States); Gibbons, John P. [Mary Bird Perkins Cancer Center, Baton Rouge, LA (United States); Department of Physics and Astronomy, Louisiana State University and Agricultural and Mechanical College, Baton Rouge, LA (United States); Lee, Tae Kyu [Mary Bird Perkins Cancer Center, Baton Rouge, LA (United States); Rosen, Isaac I. [Mary Bird Perkins Cancer Center, Baton Rouge, LA (United States); Department of Physics and Astronomy, Louisiana State University and Agricultural and Mechanical College, Baton Rouge, LA (United States); Fields, Robert S. [Mary Bird Perkins Cancer Center, Baton Rouge, LA (United States); Hogstrom, Kenneth R. [Mary Bird Perkins Cancer Center, Baton Rouge, LA (United States); Department of Physics and Astronomy, Louisiana State University and Agricultural and Mechanical College, Baton Rouge, LA (United States)

    2011-01-01T23:59:59.000Z

    Helical tomotherapy plans using a combination of pitch and jaw width settings were developed for 3 patients previously treated for head and neck cancer. Three jaw widths (5, 2.5, and 1 cm) and 4 pitches (0.86, 0.43, 0.287, and 0.215) were used with a (maximum) modulation factor setting of 4. Twelve plans were generated for each patient using an identical optimization procedure (e.g., number of iterations, objective weights, and penalties, etc.), based on recommendations from TomoTherapy (Madison, WI). The plans were compared using isodose plots, dose volume histograms, dose homogeneity indexes, conformity indexes, radiobiological models, and treatment times. Smaller pitches and jaw widths showed better target dose homogeneity and sparing of normal tissue, as expected. However, the treatment time increased inversely proportional to the jaw width, resulting in delivery times of 24 {+-} 1.9 min for the 1-cm jaw width. Although treatment plans produced with the 2.5-cm jaw were dosimetrically superior to plans produced with the 5-cm jaw, subsequent calculations of tumor control probabilities and normal tissue complication probabilities suggest that these differences may not be radiobiologically meaningful. Because treatment plans produced with the 5-cm jaw can be delivered in approximately half the time of plans produced with the 2.5-cm jaw (5.1 {+-} 0.6 min vs. 9.5 {+-} 1.1 min), use of the 5-cm jaw in routine treatment planning may be a viable approach to decreasing treatment delivery times from helical tomotherapy units.

  6. Comparative dosimetric and radiobiological assessment among a nonstandard RapidArc, standard RapidArc, classical intensity-modulated radiotherapy, and 3D brachytherapy for the treatment of the vaginal vault in patients affected by gynecologic cancer

    SciTech Connect (OSTI)

    Pedicini, Piernicola, E-mail: ppiern@libero.it [Service of Medical Physics, IRCCS Regional Cancer Hospital (C.R.O.B.), Rionero in Vulture (Italy); Caivano, Rocchina [Service of Medical Physics, IRCCS Regional Cancer Hospital (C.R.O.B.), Rionero in Vulture (Italy); Fiorentino, Alba [U.O. of Radiotherapy, IRCCS Regional Cancer Hospital (C.R.O.B.), Rionero in Vulture (Italy); Strigari, Lidia [Laboratory of Medical Physics and Expert Systems, Regina Elena National Cancer Institute, Rome (Italy); Califano, Giorgia [Service of Medical Physics, IRCCS Regional Cancer Hospital (C.R.O.B.), Rionero in Vulture (Italy); Barbieri, Viviana; Sanpaolo, Piero; Castaldo, Giovanni [U.O. of Radiotherapy, IRCCS Regional Cancer Hospital (C.R.O.B.), Rionero in Vulture (Italy); Benassi, Marcello [Service of Medical Physics, Scientific Institute of Tumors of Romagna IRST, Meldola (Italy); Fusco, Vincenzo [U.O. of Radiotherapy, IRCCS Regional Cancer Hospital (C.R.O.B.), Rionero in Vulture (Italy)

    2012-01-01T23:59:59.000Z

    To evaluate a nonstandard RapidArc (RA) modality as alternative to high-dose-rate brachytherapy (HDR-BRT) or IMRT treatments of the vaginal vault in patients with gynecological cancer (GC). Nonstandard (with vaginal applicator) and standard (without vaginal applicator) RapidArc plans for 27 women with GC were developed to compare with HDR-BRT and IMRT. Dosimetric and radiobiological comparison were performed by means of dose-volume histogram and equivalent uniform dose (EUD) for planning target volume (PTV) and organs at risk (OARs). In addition, the integral dose and the overall treatment times were evaluated. RA, as well as IMRT, results in a high uniform dose on PTV compared with HDR-BRT. However, the average of EUD for HDR-BRT was significantly higher than those with RA and IMRT. With respect to the OARs, standard RA was equivalent of IMRT but inferior to HDR-BRT. Furthermore, nonstandard RA was comparable with IMRT for bladder and sigmoid and better than HDR-BRT for the rectum because of a significant reduction of d{sub 2cc}, d{sub 1cc}, and d{sub max} (p < 0.01). Integral doses were always higher than HDR-BRT, although the values were very low. Delivery times were about the same and more than double for HDR-BRT compared with IMRT and RA, respectively. In conclusion, the boost of dose on vaginal vault in patients affected by GC delivered by a nonstandard RA technique was a reasonable alternative to the conventional HDR-BRT because of a reduction of delivery time and rectal dose at substantial comparable doses for the bladder and sigmoid. However HDR-BRT provides better performance in terms of PTV coverage as evidenced by a greater EUD.

  7. Postmastectomy radiotherapy with integrated scar boost using helical tomotherapy

    SciTech Connect (OSTI)

    Rong Yi, E-mail: rong@humonc.wisc.edu [Department of Human Oncology, University of Wisconsin, Madison, Madison, WI (United States); University of Wisconsin Riverview Cancer Center, Wisconsin Rapids, WI (United States); Yadav, Poonam [Department of Human Oncology, University of Wisconsin, Madison, Madison, WI (United States); Department of Medical Physics, University of Wisconsin, Madison, Madison, WI (United States); Vellore Institute of Technology University, Vellore, Tamil Nadu (India); Welsh, James S. [Department of Human Oncology, University of Wisconsin, Madison, Madison, WI (United States); University of Wisconsin Riverview Cancer Center, Wisconsin Rapids, WI (United States); Department of Medical Physics, University of Wisconsin, Madison, Madison, WI (United States); Fahner, Tasha [University of Wisconsin Riverview Cancer Center, Wisconsin Rapids, WI (United States); Paliwal, Bhudatt [Department of Human Oncology, University of Wisconsin, Madison, Madison, WI (United States); Department of Medical Physics, University of Wisconsin, Madison, Madison, WI (United States)

    2012-10-01T23:59:59.000Z

    The purpose of this study was to evaluate helical tomotherapy dosimetry in postmastectomy patients undergoing treatment for chest wall and positive nodal regions with simultaneous integrated boost (SIB) in the scar region using strip bolus. Six postmastectomy patients were scanned with a 5-mm-thick strip bolus covering the scar planning target volume (PTV) plus 2-cm margin. For all 6 cases, the chest wall received a total cumulative dose of 49.3-50.4 Gy with daily fraction size of 1.7-2.0 Gy. Total dose to the scar PTV was prescribed to 58.0-60.2 Gy at 2.0-2.5 Gy per fraction. The supraclavicular PTV and mammary nodal PTV received 1.7-1.9 dose per fraction. Two plans (with and without bolus) were generated for all 6 cases. To generate no-bolus plans, strip bolus was contoured and overrode to air density before planning. The setup reproducibility and delivered dose accuracy were evaluated for all 6 cases. Dose-volume histograms were used to evaluate dose-volume coverage of targets and critical structures. We observed reduced air cavities with the strip bolus setup compared with what we normally see with the full bolus. The thermoluminescence dosimeters (TLD) in vivo dosimetry confirmed accurate dose delivery beneath the bolus. The verification plans performed on the first day megavoltage computed tomography (MVCT) image verified that the daily setup and overall dose delivery was within 2% accuracy compared with the planned dose. The hotspot of the scar PTV in no-bolus plans was 111.4% of the prescribed dose averaged over 6 cases compared with 106.6% with strip bolus. With a strip bolus only covering the postmastectomy scar region, we observed increased dose uniformity to the scar PTV, higher setup reproducibility, and accurate dose delivered beneath the bolus. This study demonstrates the feasibility of using a strip bolus over the scar using tomotherapy for SIB dosimetry in postmastectomy treatments.

  8. Wavelet-Smoothed Interpolation of Masked Scientific Data for JPEG 2000 Compression

    SciTech Connect (OSTI)

    Brislawn, Christopher M. [Los Alamos National Laboratory

    2012-08-13T23:59:59.000Z

    How should we manage scientific data with 'holes'? Some applications, like JPEG 2000, expect logically rectangular data, but some sources, like the Parallel Ocean Program (POP), generate data that isn't defined on certain subsets. We refer to grid points that lack well-defined, scientifically meaningful sample values as 'masked' samples. Wavelet-smoothing is a highly scalable interpolation scheme for regions with complex boundaries on logically rectangular grids. Computation is based on forward/inverse discrete wavelet transforms, so runtime complexity and memory scale linearly with respect to sample count. Efficient state-of-the-art minimal realizations yield small constants (O(10)) for arithmetic complexity scaling, and in-situ implementation techniques make optimal use of memory. Implementation in two dimensions using tensor product filter banks is straighsorward and should generalize routinely to higher dimensions. No hand-tuning required when the interpolation mask changes, making the method aeractive for problems with time-varying masks. Well-suited for interpolating undefined samples prior to JPEG 2000 encoding. The method outperforms global mean interpolation, as judged by both SNR rate-distortion performance and low-rate artifact mitigation, for data distributions whose histograms do not take the form of sharply peaked, symmetric, unimodal probability density functions. These performance advantages can hold even for data whose distribution differs only moderately from the peaked unimodal case, as demonstrated by POP salinity data. The interpolation method is very general and is not tied to any particular class of applications, could be used for more generic smooth interpolation.

  9. Pocatello 1/sup 0/ x 2/sup 0/ NTMS area Idaho. Data report: National Uranium Resource Evaluation program, hydrogeochemical and stream sediment reconnaissance

    SciTech Connect (OSTI)

    Cook, J.R.

    1980-07-01T23:59:59.000Z

    This data report presents results of groundwater and stream/surface sediment reconnaissance in the National Topographic Map Series (NTMS) Pocatello 1/sup 0/ x 2/sup 0/ quadrangle. Surface samples (sediment) were collected from 1701 sites. The target sampling density was one site per 16 square kilometers (six square miles). Ground water samples were collected at 381 sites. Neutron activation analysis (NAA) results are given for uranium and 16 other elements in sediments, and for uranium and 9 other elements in ground water. Mass spectrometry results are given for helium in ground water. Field measurements and observations are reported for each site. Analytical data and field measurements are presented in tables and maps. Statistical summaries of data and a brief description of results are given. A generalized geologic map and a summary of the geology of the area are included. Data from sediment sites include: (1) stream water chemistry measurements where applicable (pH, conductivity, and alkalinity); and (2) elemental analyses for sediment samples (U, Th, Hf, Al, Ce, Dy, Eu, Fe, La, Lu, Mn, Sc, Sm, Na, Ti, V, and Yb). Sample site descriptors (stream characteristics, vegetation, etc.) are also tabulated. Areal distribution maps, histograms, and cumulative frequency plots for most elements; U/Th, U/Hf, and U/La ratios; and scintillometer readings for sediment sample sites are included on the microfiche. Data from groundwater sites include: (1) water chemistry measurements (pH, conductivity, and alkalinity); (2) physical measurements where applicable (water temperature, well description, and scintillometer reading); and (3) elemental analyses (U, Al, Br, Cl, Dy, F, He, Mg, Mn, Na, and V). Data from stream water sites include: (1) water chemistry measurements (pH, conductivity, and alkalinity); and (2) elemental analyses (U, Al, Br, Cl, F, Mg, Mn, Na, and V).

  10. Quantum effects and anharmonicity in the H{sub 2}-Li{sup +}-benzene complex: A model for hydrogen storage materials

    SciTech Connect (OSTI)

    Kolmann, Stephen J.; D'Arcy, Jordan H.; Jordan, Meredith J. T., E-mail: m.jordan@chem.usyd.edu.au [School of Chemistry, The University of Sydney, NSW 2006 (Australia)] [School of Chemistry, The University of Sydney, NSW 2006 (Australia)

    2013-12-21T23:59:59.000Z

    Quantum and anharmonic effects are investigated in H{sub 2}-Li{sup +}-benzene, a model for hydrogen adsorption in metal-organic frameworks and carbon-based materials. Three- and 8-dimensional quantum diffusion Monte Carlo (QDMC) and rigid-body diffusion Monte Carlo (RBDMC) simulations are performed on potential energy surfaces interpolated from electronic structure calculations at the M05-2X/6-31+G(d,p) and M05-2X/6-311+G(2df,p) levels of theory using a three-dimensional spline or a modified Shepard interpolation. These calculations investigate the intermolecular interactions in this system, with three- and 8-dimensional 0 K H{sub 2} binding enthalpy estimates, ?H{sub bind} (0 K), being 16.5 kJ mol{sup ?1} and 12.4 kJ mol{sup ?1}, respectively: 0.1 and 0.6 kJ mol{sup ?1} higher than harmonic values. Zero-point energy effects are 35% of the value of ?H{sub bind} (0 K) at M05-2X/6-311+G(2df,p) and cannot be neglected; uncorrected electronic binding energies overestimate ?H{sub bind} (0 K) by at least 6 kJ mol{sup ?1}. Harmonic intermolecular binding enthalpies can be corrected by treating the H{sub 2} “helicopter” and “ferris wheel” rotations as free and hindered rotations, respectively. These simple corrections yield results within 2% of the 8-dimensional anharmonic calculations. Nuclear ground state probability density histograms obtained from the QDMC and RBDMC simulations indicate the H{sub 2} molecule is delocalized above the Li{sup +}-benzene system at 0 K.

  11. Effect of Body Mass Index on Intrafraction Prostate Displacement Monitored by Real-Time Electromagnetic Tracking

    SciTech Connect (OSTI)

    Butler, Wayne M., E-mail: wbutler@wheelinghospital.org [Schiffler Cancer Center, Wheeling Hospital, Wheeling, West Virginia (United States); Wheeling Jesuit University, Wheeling, West Virginia (United States); Morris, Mallory N. [Schiffler Cancer Center, Wheeling Hospital, Wheeling, West Virginia (United States)] [Schiffler Cancer Center, Wheeling Hospital, Wheeling, West Virginia (United States); Merrick, Gregory S. [Schiffler Cancer Center, Wheeling Hospital, Wheeling, West Virginia (United States) [Schiffler Cancer Center, Wheeling Hospital, Wheeling, West Virginia (United States); Wheeling Jesuit University, Wheeling, West Virginia (United States); Kurko, Brian S.; Murray, Brian C. [Schiffler Cancer Center, Wheeling Hospital, Wheeling, West Virginia (United States)] [Schiffler Cancer Center, Wheeling Hospital, Wheeling, West Virginia (United States)

    2012-10-01T23:59:59.000Z

    Purpose: To evaluate, using real-time monitoring of implanted radiofrequency transponders, the intrafraction prostate displacement of patients as a function of body mass index (BMI). Methods and Materials: The motions of Beacon radiofrequency transponders (Calypso Medical Technologies, Seattle, WA) implanted in the prostate glands of 66 men were monitored throughout the course of intensity modulated radiation therapy. Data were acquired at 10 Hz from setup to the end of treatment, but only the 1.7 million data points with a 'beam on' tag were used in the analysis. There were 21 obese patients, with BMI {>=}30 and 45 nonobese patients in the study. Results: Mean displacements were least in the left-right lateral direction (0.56 {+-} 0.24 mm) and approximately twice that magnitude in the superior-inferior and anterior-posterior directions. The net vector displacement was larger still, 1.95 {+-} 0.47 mm. Stratified by BMI cohort, the mean displacements per patient in the 3 Cartesian axes as well as the net vector for patients with BMI {>=}30 were slightly less (<0.2 mm) but not significantly different than the corresponding values for patients with lower BMIs. As a surrogate for the magnitude of oscillatory noise, the standard deviation for displacements in all measured planes showed no significant differences in the prostate positional variability between the lower and higher BMI groups. Histograms of prostate displacements showed a lower frequency of large displacements in obese patients, and there were no significant differences in short-term and long-term velocity distributions. Conclusions: After patients were positioned accurately using implanted radiofrequency transponders, the intrafractional displacements in the lateral, superior-inferior, and anterior-posterior directions as well as the net vector displacements were smaller, but not significantly so, for obese men than for those with lower BMI.

  12. Missile Captive Carry Monitoring and Helicopter Identification Using a Capacitive Microelectromechanical Systems Accelerometer

    SciTech Connect (OSTI)

    Hatchell, Brian K.; Mauss, Fredrick J.; Amaya, Ivan A.; Skorpik, James R.; Silvers, Kurt L.; Marotta, Steve

    2012-03-27T23:59:59.000Z

    Military missiles are exposed to many sources of mechanical vibration that can affect system reliability, safety, and mission effectiveness. The U. S. Army Aviation and Missile Research Development and Engineering Center (AMRDEC) has been developing missile health monitoring systems to assess and improve reliability, reduce life cycle costs, and increase system readiness. One of the most significant exposures to vibration occurs when the missile is being carried by a helicopter or other aviation platform, which is a condition known as captive carry. Recording the duration of captive carry exposure during the missile’s service life can enable the implementation of predictive maintenance and resource management programs. Since the vibration imparted by each class of helicopter varies in frequency and amplitude, tracking the vibration exposure from each helicopter separately can help quantify the severity and harmonic content of the exposure. Under the direction of AMRDEC staff, engineers at the Pacific Northwest National Laboratory have developed a Captive Carry Health Monitor (CCHM) for the Hellfire II missile. The CCHM is an embedded usage monitoring device installed on the outer skin of the Hellfire II missile to record the cumulative hours the host missile has been in captive carry mode. To classify the vibration by class of helicopter, the CCHM analyzes the amplitude and frequency content of the vibration with the Goertzel algorithm to detect the presence of distinctive rotor harmonics. Cumulative usage data are accessible in theater from an external display; monthly usage histograms are accessible through an internal download connector. This paper provides an overview of the CCHM electrical and package design, describes field testing and data analysis techniques used to monitor captive carry identify and the class of helicopter, and discusses the potential application of missile health and usage data for real-time reliability analysis and fleet management.

  13. Anastomotic Complications After Ivor Lewis Esophagectomy in Patients Treated With Neoadjuvant Chemoradiation Are Related to Radiation Dose to the Gastric Fundus

    SciTech Connect (OSTI)

    Vande Walle, Caroline [Department of Gastrointestinal Surgery, University Hospital, Ghent (Belgium); Ceelen, Wim P., E-mail: wim.ceelen@ugent.be [Department of Gastrointestinal Surgery, University Hospital, Ghent (Belgium); Boterberg, Tom [Department of Radiation Oncology, University Hospital, Ghent (Belgium); Vande Putte, Dirk; Van Nieuwenhove, Yves; Varin, Oswald; Pattyn, Piet [Department of Gastrointestinal Surgery, University Hospital, Ghent (Belgium)

    2012-03-01T23:59:59.000Z

    Purpose: Neoadjuvant chemoradiation (CRT) is increasingly used in locally advanced esophageal cancer. Some studies have suggested that CRT results in increased surgical morbidity. We assessed the influence of CRT on anastomotic complications in a cohort of patients who underwent CRT followed by Ivor Lewis esophagectomy. Patients and Methods: Clinical and pathologic data were collected from all patients treated with neoadjuvant CRT (36 Gy combined with 5-fluorouracil and cisplatin) followed by Ivor Lewis esophagectomy. On the radiotherapy (RT) planning computed tomography scans, normal tissue volumes were drawn encompassing the proximal esophageal region and the gastric fundus. Within these volumes, dose-volume histograms were analyzed to generate the total dose to 50% of the volume (D{sub 50}). We studied the ability of the D{sub 50} to predict anastomotic complications (leakage, ischemia, or stenosis). Dose limits were derived using receiver operating characteristics analysis. Results: Fifty-four patients were available for analysis. RT resulted in either T or N downstaging in 51% of patients; complete pathologic response was achieved in 11%. In-hospital mortality was 5.4%, and major morbidity occurred in 36% of patients. Anastomotic complications (AC) developed in 7 patients (13%). No significant influence of the D{sub 50} on the proximal esophagus was noted on the anastomotic complication rate. The median D{sub 50} on the gastric fundus, however, was 33 Gy in patients with AC and 18 Gy in patients without AC (p = 0.024). Using receiver operating characteristics analysis, the D{sub 50} limit on the gastric fundus was defined as 29 Gy. Conclusions: In patients undergoing neoadjuvant CRT followed by Ivor Lewis esophagectomy, the incidence of AC is related to the RT dose on the gastric fundus but not to the dose received by the proximal esophagus. When planning preoperative RT, efforts should be made to limit the median dose on the gastric fundus to 29 Gy with a V{sub 30} below 40%.

  14. Population dose commitments due to radioactive releases from nuclear power plant sites in 1988

    SciTech Connect (OSTI)

    Baker, D.A. (Pacific Northwest Lab., Richland, WA (United States))

    1992-01-01T23:59:59.000Z

    Population radiation dose commitments have been estimated from reported radionuclide releases from commercial power reactors operating during 1988. Fifty-year commitments for a one-year exposure from both liquid and atmospheric releases were calculated for four population groups (infant, child, teen-ager and adult) residing between 2 and 80 km from each of 71 reactor sites. This report tabulates the results of these calculations, showing the dose commitments for both water and airborne pathways for each age group and organ. Also included for each of the sites is a histogram showing the fraction of the total population within 2 to 80 km around each site receiving various average dose commitments from the airborne pathways. The total collective dose commitments (from both liquid and airborne pathways) for each site ranged from a high of 16 person-rem to a low of 0.0011 person-rem for the sites with plants operating throughout the year with an arithmetic mean of 1.1 person-rem. The total population dose for all sites was estimated at 75 person-rem for the 150 million people considered at risk. The site average individual dose commitment from all pathways ranged from a low of 3 {times} 10{sup {minus}7} mrem to a high of 0.02 mrem. No attempt was made in this study to determine the maximum dose commitment received by any one individual from the radionuclides released at any of the sites. However, licensee calculation of doses to the maximally exposed individual at some sites indicated values of up to approximately 100 times average individual doses (on the order of a few millirem per year).

  15. Dosimetric and Radiobiological Consequences of Computed Tomography–Guided Adaptive Strategies for Intensity Modulated Radiation Therapy of the Prostate

    SciTech Connect (OSTI)

    Battista, Jerry J., E-mail: j2b@uwo.ca [Department of Medical Biophysics, Western University, London, ON (Canada); Department of Oncology, Western University, London, ON (Canada); London Regional Cancer Program, London Health Sciences Centre, London, ON (Canada); Johnson, Carol; Turnbull, David; Kempe, Jeff [London Regional Cancer Program, London Health Sciences Centre, London, ON (Canada); Bzdusek, Karl [Philips Healthcare (Radiation Oncology Systems), Fitchburg, Wisconsin (United States); Van Dyk, Jacob; Bauman, Glenn [Department of Medical Biophysics, Western University, London, ON (Canada); Department of Oncology, Western University, London, ON (Canada); London Regional Cancer Program, London Health Sciences Centre, London, ON (Canada)

    2013-12-01T23:59:59.000Z

    Purpose: To examine a range of scenarios for image-guided adaptive radiation therapy of prostate cancer, including different schedules for megavoltage CT imaging, patient repositioning, and dose replanning. Methods and Materials: We simulated multifraction dose distributions with deformable registration using 35 sets of megavoltage CT scans of 13 patients. We computed cumulative dose–volume histograms, from which tumor control probabilities and normal tissue complication probabilities (NTCPs) for rectum were calculated. Five-field intensity modulated radiation therapy (IMRT) with 18-MV x-rays was planned to achieve an isocentric dose of 76 Gy to the clinical target volume (CTV). The differences between D{sub 95}, tumor control probability, V{sub 70Gy}, and NTCP for rectum, for accumulated versus planned dose distributions, were compared for different target volume sizes, margins, and adaptive strategies. Results: The CTV D{sub 95} for IMRT treatment plans, averaged over 13 patients, was 75.2 Gy. Using the largest CTV margins (10/7 mm), the D{sub 95} values accumulated over 35 fractions were within 2% of the planned value, regardless of the adaptive strategy used. For tighter margins (5 mm), the average D{sub 95} values dropped to approximately 73.0 Gy even with frequent repositioning, and daily replanning was necessary to correct this deficit. When personalized margins were applied to an adaptive CTV derived from the first 6 treatment fractions using the STAPLE (Simultaneous Truth and Performance Level Estimation) algorithm, target coverage could be maintained using a single replan 1 week into therapy. For all approaches, normal tissue parameters (rectum V{sub 70Gy} and NTCP) remained within acceptable limits. Conclusions: The frequency of adaptive interventions depends on the size of the CTV combined with target margins used during IMRT optimization. The application of adaptive target margins (<5 mm) to an adaptive CTV determined 1 week into therapy minimizes the need for subsequent dose replanning.

  16. Helical Tomotherapy and Larynx Sparing in Advanced Oropharyngeal Carcinoma: A Dosimetric Study

    SciTech Connect (OSTI)

    Gielda, Benjamin T., E-mail: benjamin_gielda@rush.ed [Department of Radiation Oncology, Rush University Medical Center Chicago, IL (United States); Millunchick, Cheryl H.; Smart, Joseph P.; Marsh, James C.; Turian, Julius V.; Coleman, Joy L. [Department of Radiation Oncology, Rush University Medical Center Chicago, IL (United States)

    2010-10-01T23:59:59.000Z

    Intensity-modulated radiation therapy (IMRT) is gaining acceptance as a standard treatment technique for advanced squamous cell carcinoma (SCC) of the oropharynx. Dose to the uninvolved larynx and surrounding structures can pose a problem in patients with significant neck disease, potentially compromising laryngeal function and quality of life. Tomotherapy may allow greater laryngeal sparing. Seven patients with stage IV SCC of the oropharynx were replanned using Tomotherapy version 3.1. All contours/planning target volumes (PTVs) from the original plans were preserved, with the exception of the larynx, which was drawn to include all soft tissue encompassed by the thyroid/cricoid cartilage. A simultaneous integrated boost technique was used with PTV 1, 2, and 3 receiving 69.96, 59.40, and 54.00 Gy, respectively in 33 fractions. Dosimetry was evaluated via the Pinnacle treatment planning system (TPS). Equivalent uniform dose (EUD) was calculated from the dose volume histogram (DVH) using the general method with 'a' = 5.0. Mean larynx dose for all patients was 24.4 Gy. Mean EUD to the larynx was 34.2 Gy. Homogeneity was adequate; average maximum dose was 109.7% of the highest prescription. All other organs at risk (OAR) were adequately spared. Tomotherapy can spare the uninvolved larynx in the setting of advanced SCC of the oropharynx to levels that are similar to or better than those reported with other techniques. Sparing is achieved without compromising target coverage or other OAR sparing. The clinical benefit of this sparing remains to be determined in a prospective study.

  17. Preparation of activated carbon from sorghum pith and its structural and electrochemical properties

    SciTech Connect (OSTI)

    Senthilkumar, S.T.; Senthilkumar, B. [Solid State Ionics and Energy Devices Laboratory, Department of Physics, Bharathiar University, Coimbatore 641046 (India)] [Solid State Ionics and Energy Devices Laboratory, Department of Physics, Bharathiar University, Coimbatore 641046 (India); Balaji, S. [Materials Laboratory, Thiagarajar Advanced Research Center, Thiagarajar College of Engineering, Madurai 625015 (India)] [Materials Laboratory, Thiagarajar Advanced Research Center, Thiagarajar College of Engineering, Madurai 625015 (India); Sanjeeviraja, C. [Department of Physics, Alagappa University, Karaikudi 630003 (India)] [Department of Physics, Alagappa University, Karaikudi 630003 (India); Kalai Selvan, R., E-mail: selvankram@buc.edu.in [Solid State Ionics and Energy Devices Laboratory, Department of Physics, Bharathiar University, Coimbatore 641046 (India)

    2011-03-15T23:59:59.000Z

    Research highlights: {yields} Sorghum pith as the cost effective raw material for activated carbon preparation. {yields} Physicochemical method/KOH activation for preparation of activated carbon is inexpensive. {yields} Activated carbon having lower surface area surprisingly delivered a higher specific capacitance. {yields} Treated at 500 {sup o}C activated carbon exceeds maximum specific capacitances of 320.6 F/g at 10 mV/s. -- Abstract: The cost effective activated carbon (AC) has been prepared from sorghum pith by NaOH activation at various temperatures, including 300 {sup o}C (AC1), 400 {sup o}C (AC2) and 500 {sup o}C (AC3) for the electrodes in electric double layer capacitor (EDLC) applications. The amorphous nature of the samples has been observed from X-ray diffraction and Raman spectral studies. Subsequently, the surface functional groups, surface morphology, pore diameter and specific surface area have been identified through FT-IR, SEM, histogram and N{sub 2} adsorption/desorption isotherm methods. The electrochemical characterization of AC electrodes has been examined using cyclic voltammetry technique in the potential range of -0.1-1.2 V in 1.0 M H{sub 2}SO{sub 4} electrolyte at different scan rates (10, 20, 30, 40, 50 and 100 mV/s). The maximum specific capacitances of 320.6 F/g at 10 mV/s and 222.1 F/g at 100 mV/s have been obtained for AC3 electrode when compared with AC1 and AC2 electrodes. Based on the characterization studies, it has been inferred that the activated carbon prepared from sorghum pith may be one of the innovative carbon electrode materials for EDLC applications.

  18. Accelerating deactivation

    SciTech Connect (OSTI)

    FISHBACK, K.M.

    1999-02-01T23:59:59.000Z

    In recent years, the focus of the U.S. Department of Energy (DOE) complex has shifted from defense production to facility stabilization, decommissioning, and environmental restoration. This shift from production to cleanup requires a parallel shift from operations-focused management to project-focused management for an efficient facility deactivation. In the operation-focused management organization, activities are planned and executed based on production goals and are typically repetitive and cyclic. In the project-focused management environment, activities are based on a defined scope/end objective, start date, and completion date. Since the workforce used to perform production operations is also usually relied onto perform facility deactivation, it is important to shift from an operations management approach to a project management approach. It is best if the transition is accomplished quickly so the project can move forward and workers don't spend a lot of energy anticipating change. Therefore, it is essential that managers, planners, and other workers understand the key elements associated with planning a deactivation project. This paper describes a planning approach that has been used successfully to plan deactivation projects consistent with the requirements provided in DOE Order 430.1A Life Cycle Asset Management and the companion Deactivation Implementation Guide, G430. 1A-3, while exceeding schedule expectations and reducing costs. Although the planning of a deactivation project closely mirrors the classic project planning for construction projects, there are unique variations associated with facility deactivation. The key elements of planning a deactivation project are discussed relative to scope, schedule, and cost. Management tools such as project metrics and histograms are discussed as desired outputs from the planning process. In addition, lessons learned from planning deactivation projects across the DOE complex are discussed relative to making the transition from operations management to project management and the implications for deactivation project planning.

  19. Dosimetric Comparison of Involved-Field Three-Dimensional Conformal Photon Radiotherapy and Breast-Sparing Proton Therapy for the Treatment of Hodgkin's Lymphoma in Female Pediatric Patients

    SciTech Connect (OSTI)

    Andolino, David L., E-mail: dandolin@iupui.edu [Department of Radiation Oncology, Indiana University School of Medicine, Bloomington, IN (United States); Hoene, Ted [Midwest Proton Radiotherapy Institute, Bloomington, IN (United States); Xiao, Lu [Department of Radiation Oncology, Indiana University School of Medicine, Bloomington, IN (United States); Buchsbaum, Jeffrey; Chang, Andrew L. [Department of Radiation Oncology, Indiana University School of Medicine, Bloomington, IN (United States); Midwest Proton Radiotherapy Institute, Bloomington, IN (United States)

    2011-11-15T23:59:59.000Z

    Purpose: To assess the potential reduction in breast dose for young girls with Hodgkin's lymphoma (HL) treated with breast-sparing proton therapy (BS-PT) as compared with three-dimensional conformal involved-field photon radiotherapy (3D-CRT). Methods and Materials: The Clarian Health Cancer Registry was queried for female pediatric patients with the diagnosis of HL who received radiotherapy at the Indiana University Simon Cancer Center during 2006-2009. The original CT simulation images were obtained, and 3D-CRT and BS-PT plans delivering 21 Gy or cobalt gray equivalent (CGE) in 14 fractions were created for each patient. Dose-volume histogram data were collected for both 3D-CRT and BS-PT plans and compared by paired t test for correlated samples. Results: The cancer registry provided 10 female patients with Ann Arbor Stage II HL, aged 10-18 years at the time of treatment. Both mean and maximum breast dose were significantly less with BS-PT compared with 3D-CRT: 0.95 CGE vs. 4.70 Gy (p < 0.001) and 21.07 CGE vs. 23.11 Gy (p < 0.001), respectively. The volume of breast receiving 1.0 Gy/CGE and 5.0 Gy/CGE was also significantly less with BS-PT, 194 cm{sup 3} and 93 cm{sup 3}, respectively, compared with 790 cm{sup 3} and 360 cm{sup 3} with 3D-CRT (p = 0.009, 0.013). Conclusion: Breast-sparing proton therapy has the potential to reduce unnecessary breast dose in young girls with HL by as much as 80% relative to involved-field 3D-CRT.

  20. Comparison of MRI-based and CT/MRI fusion-based postimplant dosimetric analysis of prostate brachytherapy

    SciTech Connect (OSTI)

    Tanaka, Osamu [Department of Radiology, Gifu University School of Medicine, Gifu City (Japan)]. E-mail: osa-mu@umin.ac.jp; Hayashi, Shinya [Department of Radiology, Gifu University School of Medicine, Gifu City (Japan); Matsuo, Masayuki [Department of Radiology, Gifu University School of Medicine, Gifu City (Japan); Sakurai, Kota [Department of Radiology, Gifu University School of Medicine, Gifu City (Japan); Department of Urology, Gifu University School of Medicine, Gifu City (Japan); Nakano, Masahiro [Department of Urology, Gifu University School of Medicine, Gifu City (Japan); Maeda, Sunaho [Department of Radiology, Gifu University School of Medicine, Gifu City (Japan); Kajita, Kimihiro R.T. [Department of Radiology, Gifu University School of Medicine, Gifu City (Japan); Deguchi, Takashi [Department of Urology, Gifu University School of Medicine, Gifu City (Japan); Hoshi, Hiroaki [Department of Radiology, Gifu University School of Medicine, Gifu City (Japan)

    2006-10-01T23:59:59.000Z

    Purpose: The aim of this study was to compare the outcomes between magnetic resonance imaging (MRI)-based and computed tomography (CT)/MRI fusion-based postimplant dosimetry methods in permanent prostate brachytherapy. Methods and Materials: Between October 2004 and March 2006, a total of 52 consecutive patients with prostate cancer were treated by brachytherapy, and postimplant dosimetry was performed using CT/MRI fusion. The accuracy and reproducibility were prospectively compared between MRI-based dosimetry and CT/MRI fusion-based dosimetry based on the dose-volume histogram (DVH) related parameters as recommended by the American Brachytherapy Society. Results: The prostate volume was 15.97 {+-} 6.17 cc (mean {+-} SD) in MRI-based dosimetry, and 15.97 {+-} 6.02 cc in CT/MRI fusion-based dosimetry without statistical difference. The prostate V100 was 94.5% and 93.0% in MRI-based and CT/MRI fusion-based dosimetry, respectively, and the difference was statistically significant (p = 0.002). The prostate D90 was 119.4% and 114.4% in MRI-based and CT/MRI fusion-based dosimetry, respectively, and the difference was statistically significant (p = 0.004). Conclusion: Our current results suggested that, as with fusion images, MR images allowed accurate contouring of the organs, but they tended to overestimate the analysis of postimplant dosimetry in comparison to CT/MRI fusion images. Although this MRI-based dosimetric discrepancy was negligible, MRI-based dosimetry was acceptable and reproducible in comparison to CT-based dosimetry, because the difference between MRI-based and CT/MRI fusion-based results was smaller than that between CT-based and CT/MRI fusion-based results as previously reported.

  1. The first clinical implementation of electromagnetic transponder-guided MLC tracking

    SciTech Connect (OSTI)

    Keall, Paul J., E-mail: paul.keall@sydney.edu.au; O’Brien, Ricky; Ng, Jin Aun [Radiation Physics Laboratory, Sydney Medical School, University of Sydney, NSW 2006 (Australia)] [Radiation Physics Laboratory, Sydney Medical School, University of Sydney, NSW 2006 (Australia); Colvill, Emma [Radiation Physics Laboratory, Sydney Medical School, University of Sydney, NSW 2006, Australia and Northern Sydney Cancer Centre, Royal North Shore Hospital, Sydney, NSW 2065 (Australia)] [Radiation Physics Laboratory, Sydney Medical School, University of Sydney, NSW 2006, Australia and Northern Sydney Cancer Centre, Royal North Shore Hospital, Sydney, NSW 2065 (Australia); Poulsen, Per Rugaard [Department of Oncology, Aarhus University Hospital, Aarhus 8000, Denmark and Institute of Clinical Medicine, Aarhus University, Aarhus 8000 (Denmark)] [Department of Oncology, Aarhus University Hospital, Aarhus 8000, Denmark and Institute of Clinical Medicine, Aarhus University, Aarhus 8000 (Denmark); Eade, Thomas; Kneebone, Andrew; Booth, Jeremy T. [Northern Sydney Cancer Centre, Royal North Shore Hospital, Sydney, NSW 2065 (Australia)] [Northern Sydney Cancer Centre, Royal North Shore Hospital, Sydney, NSW 2065 (Australia)

    2014-02-15T23:59:59.000Z

    Purpose: We report on the clinical process, quality assurance, and geometric and dosimetric results of the first clinical implementation of electromagnetic transponder-guided MLC tracking which occurred on 28 November 2013 at the Northern Sydney Cancer Centre. Methods: An electromagnetic transponder-based positioning system (Calypso) was modified to send the target position output to in-house-developed MLC tracking code, which adjusts the leaf positions to optimally align the treatment beam with the real-time target position. Clinical process and quality assurance procedures were developed and performed. The first clinical implementation of electromagnetic transponder-guided MLC tracking was for a prostate cancer patient being treated with dual-arc VMAT (RapidArc). For the first fraction of the first patient treatment of electromagnetic transponder-guided MLC tracking we recorded the in-room time and transponder positions, and performed dose reconstruction to estimate the delivered dose and also the dose received had MLC tracking not been used. Results: The total in-room time was 21 min with 2 min of beam delivery. No additional time was needed for MLC tracking and there were no beam holds. The average prostate position from the initial setup was 1.2 mm, mostly an anterior shift. Dose reconstruction analysis of the delivered dose with MLC tracking showed similar isodose and target dose volume histograms to the planned treatment and a 4.6% increase in the fractional rectal V{sub 60}. Dose reconstruction without motion compensation showed a 30% increase in the fractional rectal V{sub 60} from that planned, even for the small motion. Conclusions: The real-time beam-target correction method, electromagnetic transponder-guided MLC tracking, has been translated to the clinic. This achievement represents a milestone in improving geometric and dosimetric accuracy, and by inference treatment outcomes, in cancer radiotherapy.

  2. A Fully Automated Method for CT-on-Rails-Guided Online Adaptive Planning for Prostate Cancer Intensity Modulated Radiation Therapy

    SciTech Connect (OSTI)

    Li, Xiaoqiang; Quan, Enzhuo M.; Li, Yupeng [Department of Radiation Physics, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Pan, Xiaoning [Department of Radiation Oncology, University of Texas Health Science Center at Tyler, Tyler, Texas (United States); Zhou, Yin [Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Wang, Xiaochun [Department of Radiation Physics, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Du, Weiliang [Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Kudchadker, Rajat J.; Johnson, Jennifer L. [Department of Radiation Physics, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Kuban, Deborah A.; Lee, Andrew K. [Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Zhang, Xiaodong, E-mail: xizhang@mdanderson.org [Department of Radiation Physics, University of Texas MD Anderson Cancer Center, Houston, Texas (United States)

    2013-08-01T23:59:59.000Z

    Purpose: This study was designed to validate a fully automated adaptive planning (AAP) method which integrates automated recontouring and automated replanning to account for interfractional anatomical changes in prostate cancer patients receiving adaptive intensity modulated radiation therapy (IMRT) based on daily repeated computed tomography (CT)-on-rails images. Methods and Materials: Nine prostate cancer patients treated at our institution were randomly selected. For the AAP method, contours on each repeat CT image were automatically generated by mapping the contours from the simulation CT image using deformable image registration. An in-house automated planning tool incorporated into the Pinnacle treatment planning system was used to generate the original and the adapted IMRT plans. The cumulative dose–volume histograms (DVHs) of the target and critical structures were calculated based on the manual contours for all plans and compared with those of plans generated by the conventional method, that is, shifting the isocenters by aligning the images based on the center of the volume (COV) of prostate (prostate COV-aligned). Results: The target coverage from our AAP method for every patient was acceptable, while 1 of the 9 patients showed target underdosing from prostate COV-aligned plans. The normalized volume receiving at least 70 Gy (V{sub 70}), and the mean dose of the rectum and bladder were reduced by 8.9%, 6.4 Gy and 4.3%, 5.3 Gy, respectively, for the AAP method compared with the values obtained from prostate COV-aligned plans. Conclusions: The AAP method, which is fully automated, is effective for online replanning to compensate for target dose deficits and critical organ overdosing caused by interfractional anatomical changes in prostate cancer.

  3. The Residual Setup Errors of Different IGRT Alignment Procedures for Head and Neck IMRT and the Resulting Dosimetric Impact

    SciTech Connect (OSTI)

    Graff, Pierre [Department of Radiation-Oncology, Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, California (United States) [Department of Radiation-Oncology, Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, California (United States); Radiation-Oncology, Alexis Vautrin Cancer Center, Vandoeuvre-Les-Nancy (France); Doctoral School BioSE (EA4360), Nancy (France); Kirby, Neil [Department of Radiation-Oncology, Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, California (United States)] [Department of Radiation-Oncology, Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, California (United States); Weinberg, Vivian [Department of Radiation-Oncology, Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, California (United States) [Department of Radiation-Oncology, Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, California (United States); Department of Biostatistics, Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, California (United States); Chen, Josephine; Yom, Sue S. [Department of Radiation-Oncology, Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, California (United States)] [Department of Radiation-Oncology, Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, California (United States); Lambert, Louise [Department of Radiation-Oncology, Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, California (United States) [Department of Radiation-Oncology, Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, California (United States); Radiation-Oncology, Montreal University Centre, Montreal (Canada); Pouliot, Jean, E-mail: jpouliot@radonc.ucsf.edu [Department of Radiation-Oncology, Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, California (United States)] [Department of Radiation-Oncology, Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, California (United States)

    2013-05-01T23:59:59.000Z

    Purpose: To assess residual setup errors during head and neck radiation therapy and the resulting consequences for the delivered dose for various patient alignment procedures. Methods and Materials: Megavoltage cone beam computed tomography (MVCBCT) scans from 11 head and neck patients who underwent intensity modulated radiation therapy were used to assess setup errors. Each MVCBCT scan was registered to its reference planning kVCT, with seven different alignment procedures: automatic alignment and manual registration to 6 separate bony landmarks (sphenoid, left/right maxillary sinuses, mandible, cervical 1 [C1]-C2, and C7-thoracic 1 [T1] vertebrae). Shifts in the different alignments were compared with each other to determine whether there were any statistically significant differences. Then, the dose distribution was recalculated on 3 MVCBCT images per patient for every alignment procedure. The resulting dose-volume histograms for targets and organs at risk (OARs) were compared to those from the planning kVCTs. Results: The registration procedures produced statistically significant global differences in patient alignment and actual dose distribution, calling for a need for standardization of patient positioning. Vertically, the automatic, sphenoid, and maxillary sinuses alignments mainly generated posterior shifts and resulted in mean increases in maximal dose to OARs of >3% of the planned dose. The suggested choice of C1-C2 as a reference landmark appears valid, combining both OAR sparing and target coverage. Assuming this choice, relevant margins to apply around volumes of interest at the time of planning to take into account for the relative mobility of other regions are discussed. Conclusions: Use of different alignment procedures for treating head and neck patients produced variations in patient setup and dose distribution. With concern for standardizing practice, C1-C2 reference alignment with relevant margins around planning volumes seems to be a valid option.

  4. Relative Importance of Hip and Sacral Pain Among Long-Term Gynecological Cancer Survivors Treated With Pelvic Radiotherapy and Their Relationships to Mean Absorbed Doses

    SciTech Connect (OSTI)

    Waldenstroem, Ann-Charlotte, E-mail: ann-charlotte.waldenstrom@oncology.gu.se [Division of Clinical Cancer Epidemiology, Department of Oncology, Institute of Clinical Sciences, Sahlgrenska Academy at University of Gothenburg, Gothenburg (Sweden) [Division of Clinical Cancer Epidemiology, Department of Oncology, Institute of Clinical Sciences, Sahlgrenska Academy at University of Gothenburg, Gothenburg (Sweden); Department of Oncology, Sahlgrenska University Hospital, Gothenburg (Sweden); Olsson, Caroline [Division of Clinical Cancer Epidemiology, Department of Oncology, Institute of Clinical Sciences, Sahlgrenska Academy at University of Gothenburg, Gothenburg (Sweden) [Division of Clinical Cancer Epidemiology, Department of Oncology, Institute of Clinical Sciences, Sahlgrenska Academy at University of Gothenburg, Gothenburg (Sweden); Department of Radiation Physics, Institute of Clinical Sciences, Sahlgrenska Academy at University of Gothenburg, Gothenburg (Sweden); Wilderaeng, Ulrica [Division of Clinical Cancer Epidemiology, Department of Oncology, Institute of Clinical Sciences, Sahlgrenska Academy at University of Gothenburg, Gothenburg (Sweden)] [Division of Clinical Cancer Epidemiology, Department of Oncology, Institute of Clinical Sciences, Sahlgrenska Academy at University of Gothenburg, Gothenburg (Sweden); Dunberger, Gail; Lind, Helena; Alevronta, Eleftheria [Division of Clinical Cancer Epidemiology, Department of Oncology-Pathology, Karolinska Institute, Stockholm (Sweden)] [Division of Clinical Cancer Epidemiology, Department of Oncology-Pathology, Karolinska Institute, Stockholm (Sweden); Al-Abany, Massoud [Division of Clinical Cancer Epidemiology, Department of Oncology-Pathology, Karolinska Institute, Stockholm (Sweden) [Division of Clinical Cancer Epidemiology, Department of Oncology-Pathology, Karolinska Institute, Stockholm (Sweden); Department of Hospital Physics, Karolinska University Hospital, Stockholm (Sweden); Tucker, Susan [Department of Bioinformatics and Computational Biology, University of Texas M. D. Anderson Cancer Center, Houston, TX (United States)] [Department of Bioinformatics and Computational Biology, University of Texas M. D. Anderson Cancer Center, Houston, TX (United States); Avall-Lundqvist, Elisabeth [Department of Gynecologic Oncology, Karolinska University Hospital, Stockholm (Sweden)] [Department of Gynecologic Oncology, Karolinska University Hospital, Stockholm (Sweden); Johansson, Karl-Axel [Department of Physics and Biomedical Engineering, Sahlgrenska University Hospital, Gothenburg (Sweden)] [Department of Physics and Biomedical Engineering, Sahlgrenska University Hospital, Gothenburg (Sweden); Steineck, Gunnar [Division of Clinical Cancer Epidemiology, Department of Oncology, Institute of Clinical Sciences, Sahlgrenska Academy at University of Gothenburg, Gothenburg (Sweden) [Division of Clinical Cancer Epidemiology, Department of Oncology, Institute of Clinical Sciences, Sahlgrenska Academy at University of Gothenburg, Gothenburg (Sweden); Division of Clinical Cancer Epidemiology, Department of Oncology-Pathology, Karolinska Institute, Stockholm (Sweden)

    2012-10-01T23:59:59.000Z

    Purpose: To investigate the relative importance of patient-reported hip and sacral pain after pelvic radiotherapy (RT) for gynecological cancer and its relationship to the absorbed doses in these organs. Methods and Materials: We used data from a population-based study that included 650 long-term gynecological cancer survivors treated with pelvic RT in the Gothenburg and Stockholm areas in Sweden with a median follow-up of 6 years (range, 2-15) and 344 population controls. Symptoms were assessed through a study-specific postal questionnaire. We also analyzed the hip and sacral dose-volume histogram data for 358 of the survivors. Results: Of the survivors, one in three reported having or having had hip pain after completing RT. Daily pain when walking was four times as common among the survivors compared to controls. Symptoms increased in frequency with a mean absorbed dose >37.5 Gy. Also, two in five survivors reported pain in the sacrum. Sacral pain also affected their walking ability and tended to increase with a mean absorbed dose >42.5 Gy. Conclusions: Long-term survivors of gynecological cancer treated with pelvic RT experience hip and sacral pain when walking. The mean absorbed dose was significantly related to hip pain and was borderline significantly related to sacral pain. Keeping the total mean absorbed hip dose below 37.5 Gy during treatment might lower the occurrence of long-lasting pain. In relation to the controls, the survivors had a lower occurrence of pain and pain-related symptoms from the hips and sacrum compared with what has previously been reported for the pubic bone.

  5. Implications of Intercellular Signaling for Radiation Therapy: A Theoretical Dose-Planning Study

    SciTech Connect (OSTI)

    McMahon, Stephen J., E-mail: stephen.mcmahon@qub.ac.uk [Centre for Cancer Research and Cell Biology, Queen's University Belfast, Belfast, Northern Ireland (United Kingdom); McGarry, Conor K. [Centre for Cancer Research and Cell Biology, Queen's University Belfast, Belfast, Northern Ireland (United Kingdom); Radiotherapy Physics, Northern Ireland Cancer Centre, Belfast Health and Social Care Trust, Belfast, Northern Ireland (United Kingdom); Butterworth, Karl T. [Centre for Cancer Research and Cell Biology, Queen's University Belfast, Belfast, Northern Ireland (United Kingdom); O'Sullivan, Joe M. [Centre for Cancer Research and Cell Biology, Queen's University Belfast, Belfast, Northern Ireland (United Kingdom); Clinical Oncology, Northern Ireland Cancer Centre, Belfast Health and Social Care Trust, Belfast, Northern Ireland (United Kingdom); Hounsell, Alan R. [Centre for Cancer Research and Cell Biology, Queen's University Belfast, Belfast, Northern Ireland (United Kingdom); Radiotherapy Physics, Northern Ireland Cancer Centre, Belfast Health and Social Care Trust, Belfast, Northern Ireland (United Kingdom); Prise, Kevin M. [Centre for Cancer Research and Cell Biology, Queen's University Belfast, Belfast, Northern Ireland (United Kingdom)

    2013-12-01T23:59:59.000Z

    Purpose: Recent in vitro results have shown significant contributions to cell killing from signaling effects at doses that are typically used in radiation therapy. This study investigates whether these in vitro observations can be reconciled with in vivo knowledge and how signaling may have an impact on future developments in radiation therapy. Methods and Materials: Prostate cancer treatment plans were generated for a series of 10 patients using 3-dimensional conformal therapy, intensity modulated radiation therapy (IMRT), and volumetric modulated arc therapy techniques. These plans were evaluated using mathematical models of survival following modulated radiation exposures that were developed from in vitro observations and incorporate the effects of intercellular signaling. The impact on dose–volume histograms and mean doses were evaluated by converting these survival levels into “signaling-adjusted doses” for comparison. Results: Inclusion of intercellular communication leads to significant differences between the signalling-adjusted and physical doses across a large volume. Organs in low-dose regions near target volumes see the largest increases, with mean signaling-adjusted bladder doses increasing from 23 to 33 Gy in IMRT plans. By contrast, in high-dose regions, there is a small decrease in signaling-adjusted dose due to reduced contributions from neighboring cells, with planning target volume mean doses falling from 74 to 71 Gy in IMRT. Overall, however, the dose distributions remain broadly similar, and comparisons between the treatment modalities are largely unchanged whether physical or signaling-adjusted dose is compared. Conclusions: Although incorporating cellular signaling significantly affects cell killing in low-dose regions and suggests a different interpretation for many phenomena, their effect in high-dose regions for typical planning techniques is comparatively small. This indicates that the significant signaling effects observed in vitro are not contradicted by comparison with clinical observations. Future investigations are needed to validate these effects in vivo and to quantify their ranges and potential impact on more advanced radiation therapy techniques.

  6. Critical dose and toxicity index of organs at risk in radiotherapy: Analyzing the calculated effects of modified dose fractionation in non–small cell lung cancer

    SciTech Connect (OSTI)

    Pedicini, Piernicola, E-mail: ppiern@libero.it [Service of Medical Physics, I.R.C.C.S. Regional Cancer Hospital C.R.O.B, Rionero in Vulture (Italy); Strigari, Lidia [Laboratory of Medical Physics and Expert Systems, Regina Elena National Cancer Institute, Rome (Italy); Benassi, Marcello [Service of Medical Physics, Scientific Institute of Tumours of Romagna I.R.S.T., Meldola (Italy); Caivano, Rocchina [Service of Medical Physics, I.R.C.C.S. Regional Cancer Hospital C.R.O.B, Rionero in Vulture (Italy); Fiorentino, Alba [U.O. of Radiotherapy, I.R.C.C.S. Regional Cancer Hospital C.R.O.B., Rionero in Vulture (Italy); Nappi, Antonio [U.O. of Nuclear Medicine, I.R.C.C.S. Regional Cancer Hospital C.R.O.B., Rionero in Vulture (Italy); Salvatore, Marco [U.O. of Nuclear Medicine, I.R.C.C.S. SDN Foundation, Naples (Italy); Storto, Giovanni [U.O. of Nuclear Medicine, I.R.C.C.S. Regional Cancer Hospital C.R.O.B., Rionero in Vulture (Italy)

    2014-04-01T23:59:59.000Z

    To increase the efficacy of radiotherapy for non–small cell lung cancer (NSCLC), many schemes of dose fractionation were assessed by a new “toxicity index” (I), which allows one to choose the fractionation schedules that produce less toxic treatments. Thirty-two patients affected by non resectable NSCLC were treated by standard 3-dimensional conformal radiotherapy (3DCRT) with a strategy of limited treated volume. Computed tomography datasets were employed to re plan by simultaneous integrated boost intensity-modulated radiotherapy (IMRT). The dose distributions from plans were used to test various schemes of dose fractionation, in 3DCRT as well as in IMRT, by transforming the dose-volume histogram (DVH) into a biological equivalent DVH (BDVH) and by varying the overall treatment time. The BDVHs were obtained through the toxicity index, which was defined for each of the organs at risk (OAR) by a linear quadratic model keeping an equivalent radiobiological effect on the target volume. The less toxic fractionation consisted in a severe/moderate hyper fractionation for the volume including the primary tumor and lymph nodes, followed by a hypofractionation for the reduced volume of the primary tumor. The 3DCRT and IMRT resulted, respectively, in 4.7% and 4.3% of dose sparing for the spinal cord, without significant changes for the combined-lungs toxicity (p < 0.001). Schedules with reduced overall treatment time (accelerated fractionations) led to a 12.5% dose sparing for the spinal cord (7.5% in IMRT), 8.3% dose sparing for V{sub 20} in the combined lungs (5.5% in IMRT), and also significant dose sparing for all the other OARs (p < 0.001). The toxicity index allows to choose fractionation schedules with reduced toxicity for all the OARs and equivalent radiobiological effect for the tumor in 3DCRT, as well as in IMRT, treatments of NSCLC.

  7. Marble Canyon 1/sup 0/ x 2/sup 0/ NTMS area Arizona: data report

    SciTech Connect (OSTI)

    Heffner, J.D.

    1980-07-01T23:59:59.000Z

    Results of ground water and stream/surface sediment reconnaissance (HSSR) in the National Topographic Map Series (NTMS) Marble Canyon 1/sup 0/ x 2/sup 0/ quadrangle are presented. The target sampling density for all media collected was one site per 12 square kilometers. This resulted in 884 sediment samples being collected; however, dry conditions and sparse population resulted in the collection of only 2 ground water samples. Grand Canyon National Park, Glen Canyon National Recreation Area, and much Indian tribal land in the southern half of the quadrangle were not sampled. Neutron activation analysis (NAA) results are given for uranium and 16 other elements in sediments, and for uranium and 9 other elements in ground water. Mass spectrometry results are given for helium in ground water. Field measurements for sediment samples are presented in tables and maps. Statistical summaries of data and a brief description of results are given. A generalized geologic map and a summary of the geology of the area are included. Data from ground water include: water chemistry measurements (pH, conductivity, and alkalinity); physical measurements (water temperature, and scintillometer readings); and elemental analyses (U, Al, Br, Cl, Dy, F, He, Mg, Mn, Na, and V). Data from sediment sites include: water chemistry measurements (where available) for pH, conductivity, and alkalinity; and elemental analyses(U, Th, Hf, Al, Ce, Dy, Eu, Fe, La, Lu, Mn, Sc, Sm, Na, Ti, V, and Yb). Sample site descriptors (stream characteristics, vegetation, etc.) are also tabulated. Histograms, cumulative frequency, and areal distribution plots for most elements; Log U/Th, Log U/Hf, and Log U/(Th + Hf) ratios; and scintillometer readings are included.

  8. Relationship of Imaging Frequency and Planning Margin to Account for Intrafraction Prostate Motion: Analysis Based on Real-Time Monitoring Data

    SciTech Connect (OSTI)

    Curtis, William [School of Medicine, Case Western Reserve University, Cleveland, Ohio (United States)] [School of Medicine, Case Western Reserve University, Cleveland, Ohio (United States); Khan, Mohammad; Magnelli, Anthony; Stephans, Kevin; Tendulkar, Rahul [Department of Radiation Oncology, Cleveland Clinic, Cleveland, Ohio (United States)] [Department of Radiation Oncology, Cleveland Clinic, Cleveland, Ohio (United States); Xia, Ping, E-mail: xiap@ccf.org [Department of Radiation Oncology, Cleveland Clinic, Cleveland, Ohio (United States)] [Department of Radiation Oncology, Cleveland Clinic, Cleveland, Ohio (United States)

    2013-03-01T23:59:59.000Z

    Purpose: Correction for intrafraction prostate motion becomes important for hypofraction treatment of prostate cancer. The purpose of this study was to estimate an ideal planning margin to account for intrafraction prostate motion as a function of imaging and repositioning frequency in the absence of continuous prostate motion monitoring. Methods and Materials: For 31 patients receiving intensity modulated radiation therapy treatment, prostate positions sampled at 10 Hz during treatment using the Calypso system were analyzed. Using these data, we simulated multiple, less frequent imaging protocols, including intervals of every 10, 15, 20, 30, 45, 60, 90, 120, 180, and 240 seconds. For each imaging protocol, the prostate displacement at the imaging time was corrected by subtracting prostate shifts from the subsequent displacements in that fraction. Furthermore, we conducted a principal component analysis to quantify the direction of prostate motion. Results: Averaging histograms of every 240 and 60 seconds for all patients, vector displacements of the prostate were, respectively, within 3 and 2 mm for 95% of the treatment time. A vector margin of 1 mm achieved 91.2% coverage of the prostate with 30 second imaging. The principal component analysis for all fractions showed the largest variance in prostate position in the midsagittal plane at 54° from the anterior direction, indicating that anterosuperior to inferoposterior is the direction of greatest motion. The smallest prostate motion is in the left-right direction. Conclusions: The magnitudes of intrafraction prostate motion along the superior-inferior and anterior-posterior directions are comparable, and the smallest motion is in the left-right direction. In the absence of continuous prostate motion monitoring, and under ideal circumstances, 1-, 2-, and 3-mm vector planning margins require a respective imaging frequency of every 15, 60, and 240 to account for intrafraction prostate motion while achieving adequate geometric target coverage for 95% of the time.

  9. Probabilities of Radiation Myelopathy Specific to Stereotactic Body Radiation Therapy to Guide Safe Practice

    SciTech Connect (OSTI)

    Sahgal, Arjun, E-mail: arjun.sahgal@rmp.uhn.on.ca [Department of Radiation Oncology, Princess Margaret Hospital, University of Toronto, Toronto, ON (Canada) [Department of Radiation Oncology, Princess Margaret Hospital, University of Toronto, Toronto, ON (Canada); Department of Radiation Oncology, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, ON (Canada); Weinberg, Vivian [University of California San Francisco Helen Diller Family Comprehensive Cancer Center Biostatistics Core, San Francisco, California (United States)] [University of California San Francisco Helen Diller Family Comprehensive Cancer Center Biostatistics Core, San Francisco, California (United States); Ma, Lijun [Department of Radiation Oncology, University of California at San Francisco, San Francisco, California (United States)] [Department of Radiation Oncology, University of California at San Francisco, San Francisco, California (United States); Chang, Eric [Department of Radiation Oncology, University of Southern California and University of Texas MD Anderson Cancer Center, University of Texas, Houston, Texas (United States)] [Department of Radiation Oncology, University of Southern California and University of Texas MD Anderson Cancer Center, University of Texas, Houston, Texas (United States); Chao, Sam [Department of Radiation Oncology and Neurosurgery, Cleveland Clinic, Cleveland, Ohio (United States)] [Department of Radiation Oncology and Neurosurgery, Cleveland Clinic, Cleveland, Ohio (United States); Muacevic, Alexander [European Cyberknife Center Munich in affiliation with University Hospitals of Munich, Munich (Germany)] [European Cyberknife Center Munich in affiliation with University Hospitals of Munich, Munich (Germany); Gorgulho, Alessandra [Department of Neurosurgery, University of California at Los Angeles, Los Angeles, California (United States)] [Department of Neurosurgery, University of California at Los Angeles, Los Angeles, California (United States); Soltys, Scott [Department of Radiation Oncology, Stanford University, Stanford, California (United States)] [Department of Radiation Oncology, Stanford University, Stanford, California (United States); Gerszten, Peter C. [Departments of Neurological Surgery and Radiation Oncology, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania (United States)] [Departments of Neurological Surgery and Radiation Oncology, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania (United States); Ryu, Sam [Department of Radiation Oncology, Henry Ford Hospital, Detroit, Michigan (United States)] [Department of Radiation Oncology, Henry Ford Hospital, Detroit, Michigan (United States); Angelov, Lilyana [Department of Radiation Oncology and Neurosurgery, Cleveland Clinic, Cleveland, Ohio (United States)] [Department of Radiation Oncology and Neurosurgery, Cleveland Clinic, Cleveland, Ohio (United States); Gibbs, Iris [Department of Radiation Oncology, Stanford University, Stanford, California (United States)] [Department of Radiation Oncology, Stanford University, Stanford, California (United States); Wong, C. Shun [Department of Radiation Oncology, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, ON (Canada)] [Department of Radiation Oncology, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, ON (Canada); Larson, David A. [Department of Radiation Oncology, University of California at San Francisco, San Francisco, California (United States)] [Department of Radiation Oncology, University of California at San Francisco, San Francisco, California (United States)

    2013-02-01T23:59:59.000Z

    Purpose: Dose-volume histogram (DVH) results for 9 cases of post spine stereotactic body radiation therapy (SBRT) radiation myelopathy (RM) are reported and compared with a cohort of 66 spine SBRT patients without RM. Methods and Materials: DVH data were centrally analyzed according to the thecal sac point maximum (Pmax) volume, 0.1- to 1-cc volumes in increments of 0.1 cc, and to the 2 cc volume. 2-Gy biologically equivalent doses (nBED) were calculated using an {alpha}/{beta} = 2 Gy (units = Gy{sub 2/2}). For the 2 cohorts, the nBED means and distributions were compared using the t test and Mann-Whitney test, respectively. Significance (P<.05) was defined as concordance of both tests at each specified volume. A logistic regression model was developed to estimate the probability of RM using the dose distribution for a given volume. Results: Significant differences in both the means and distributions at the Pmax and up to the 0.8-cc volume were observed. Concordant significance was greatest for the Pmax volume. At the Pmax volume the fit of the logistic regression model, summarized by the area under the curve, was 0.87. A risk of RM of 5% or less was observed when limiting the thecal sac Pmax volume doses to 12.4 Gy in a single fraction, 17.0 Gy in 2 fractions, 20.3 Gy in 3 fractions, 23.0 Gy in 4 fractions, and 25.3 Gy in 5 fractions. Conclusion: We report the first logistic regression model yielding estimates for the probability of human RM specific to SBRT.

  10. SU-E-T-86: Comparison of Two Commercially Available Programs for the Evaluation of Delivered Daily Dose Using Cone Beam CT (CBCT)

    SciTech Connect (OSTI)

    Tuohy, R; Bosse, C; Mavroidis, P; Shi, Z; Crownover, R; Papanikolaou, N; Stathakis, S [University of Texas Health Science Center, UTHSCSA, San Antonio, TX (United States)

    2014-06-01T23:59:59.000Z

    Purpose: In this study, two commercially available programs were compared for the evaluation of delivered daily dose using cone beam CT (CBCT). Methods: Thirty (n=30) patients previously treated in our clinic (10 prostate, 10 SBRT lung and 10 abdomen) were used in this study. The patients' plans were optimized and calculated using the Pinnacle treatment planning system. The daily CBCT scans were imported into Velocity and RayStation along with the corresponding planning CTs, structure sets and 3D dose distributions for each patient. The organs at risk (OAR) were contoured on each CBCT by the prescribing physician and were included in the evaluation of the daily delivered dose. Each CBCT was registered to the planning CT, once with rigid registration and then again, separately, with deformable registration. After registering each CBCT, the dose distribution from the planning CT was overlaid and the dose volume histograms (DVH) for the OAR and the planning target volumes (PTV) were calculated. Results: For prostate patients, we observed daily volume changes for the OARs. The DVH analysis for those patients showed variation in the sparing of the OARs while PTV coverage remained virtually unchanged using both Velocity and RayStation systems. Similar results were observed for abdominal patients. In contrast, for SBRT lung patients, the DVH for the OARs and target were comparable to those from the initial treatment plan. Differences in organ volume and organ doses were also observed when comparing the daily fractions using deformable and rigid registrations. Conclusion: By using daily CBCT dose reconstruction, we proved PTV coverage for prostate and abdominal targets is adequate. However, there is significant dosimetric change for the OARs. For lung SBRT patients, the delivered daily dose for both PTV and OAR is comparable to the planned dose with no significant differences.

  11. Dosimetric and Clinical Outcomes of Involved-Field Intensity-Modulated Radiotherapy After Chemotherapy for Early-Stage Hodgkin's Lymphoma With Mediastinal Involvement

    SciTech Connect (OSTI)

    Lu Ningning [Department of Radiation Oncology, Cancer Hospital, National Cancer Center, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing (China)] [Department of Radiation Oncology, Cancer Hospital, National Cancer Center, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing (China); Li Yexiong, E-mail: yexiong@yahoo.com [Department of Radiation Oncology, Cancer Hospital, National Cancer Center, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing (China); Wu Runye; Zhang Ximei; Wang Weihu; Jin Jing; Song Yongwen; Fang Hui; Ren Hua; Wang Shulian; Liu Yueping; Liu Xinfan; Chen Bo; Dai Jianrong; Yu Zihao [Department of Radiation Oncology, Cancer Hospital, National Cancer Center, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing (China)] [Department of Radiation Oncology, Cancer Hospital, National Cancer Center, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing (China)

    2012-09-01T23:59:59.000Z

    Purpose: To evaluate the dosimetric and clinical outcomes of involved-field intensity-modulated radiotherapy (IF-IMRT) for patients with early-stage Hodgkin's lymphoma (HL) with mediastinal involvement. Methods and Materials: Fifty-two patients with early-stage HL that involved the mediastinum were reviewed. Eight patients had Stage I disease, and 44 patients had Stage II disease. Twenty-three patients (44%) presented with a bulky mediastinum, whereas 42 patients (81%) had involvement of both the mediastinum and either cervical or axillary nodes. All patients received combination chemotherapy followed by IF-IMRT. The prescribed radiation dose was 30-40 Gy. The dose-volume histograms of the target volume and critical normal structures were evaluated. Results: The median mean dose to the primary involved regions (planning target volume, PTV1) and boost area (PTV2) was 37.5 Gy and 42.1 Gy, respectively. Only 0.4% and 1.3% of the PTV1 and 0.1% and 0.5% of the PTV2 received less than 90% and 95% of the prescribed dose, indicating excellent PTV coverage. The median mean lung dose and V20 to the lungs were 13.8 Gy and 25.9%, respectively. The 3-year overall survival, local control, and progression-free survival rates were 100%, 97.9%, and 96%, respectively. No Grade 4 or 5 acute or late toxicities were reported. Conclusions: Despite the large target volume, IF-IMRT gave excellent dose coverage and a favorable prognosis, with mild toxicity in patients with early-stage mediastinal HL.

  12. SU-E-J-190: Characterization of Radiation Induced CT Number Changes in Tumor and Normal Lung During Radiation Therapy for Lung Cancer

    SciTech Connect (OSTI)

    Yang, C; Liu, F; Tai, A; Gore, E; Johnstone, C; Li, X [Medical College of Wisconsin Milwaukee WI (United States)

    2014-06-01T23:59:59.000Z

    Purpose: To measure CT number (CTN) changes in tumor and normal lung as a function of radiation therapy (RT) dose during the course of RT delivery for lung cancer using daily IGRT CT images and single respiration phase CT images. Methods: 4D CT acquired during planning simulation and daily 3D CT acquired during daily IGRT for 10 lung cancer cases randomly selected in terms of age, caner type and stage, were analyzed using an in-house developed software tool. All patients were treated in 2 Gy fractions to primary tumors and involved nodal regions. Regions enclosed by a series of isodose surfaces in normal lung were delineated. The obtained contours along with target contours (GTVs) were populated to each singlephase planning CT and daily CT. CTN in term of Hounsfield Unit (HU) of each voxel in these delineated regions were collectively analyzed using histogram, mean, mode and linear correlation. Results: Respiration induced normal lung CTN change, as analyzed from single-phase planning CTs, ranged from 9 to 23 (±2) HU for the patients studied. Normal lung CTN change was as large as 50 (±12) HU over the entire treatment course, was dose and patient dependent and was measurable with dose changes as low as 1.5 Gy. For patients with obvious tumor volume regression, CTN within the GTV drops monotonically as much as 10 (±1) HU during the early fractions with a total dose of 20 Gy delivered. The GTV and CTN reductions are significantly correlated with correlation coefficient >0.95. Conclusion: Significant RT dose induced CTN changes in lung tissue and tumor region can be observed during even the early phase of RT delivery, and may potentially be used for early prediction of radiation response. Single respiration phase CT images have dramatically reduced statistical noise in ROIs, making daily dose response evaluation possible.

  13. Novel multimodality segmentation using level sets and Jensen-Rényi divergence

    SciTech Connect (OSTI)

    Markel, Daniel, E-mail: daniel.markel@mail.mcgill.ca [Medical Physics Unit, University of McGill, Montreal, Quebec H3H 2R9 (Canada)] [Medical Physics Unit, University of McGill, Montreal, Quebec H3H 2R9 (Canada); Zaidi, Habib [Division of Nuclear Medicine and Molecular Imaging, Geneva University Hospital, CH-1211 Geneva (Switzerland) [Division of Nuclear Medicine and Molecular Imaging, Geneva University Hospital, CH-1211 Geneva (Switzerland); Geneva Neuroscience Center, Geneva University, CH-1205 Geneva (Switzerland); Department of Nuclear Medicine and Molecular Imaging, University of Groningen, University Medical Center Groningen, Groningen P.O. Box 30 001 (Netherlands); El Naqa, Issam [Faculty of Medicine, Department of Oncology, Medical Physics Unit, McGill University, Montreal, Quebec H3G 1A4 (Canada)] [Faculty of Medicine, Department of Oncology, Medical Physics Unit, McGill University, Montreal, Quebec H3G 1A4 (Canada)

    2013-12-15T23:59:59.000Z

    Purpose: Positron emission tomography (PET) is playing an increasing role in radiotherapy treatment planning. However, despite progress, robust algorithms for PET and multimodal image segmentation are still lacking, especially if the algorithm were extended to image-guided and adaptive radiotherapy (IGART). This work presents a novel multimodality segmentation algorithm using the Jensen-Rényi divergence (JRD) to evolve the geometric level set contour. The algorithm offers improved noise tolerance which is particularly applicable to segmentation of regions found in PET and cone-beam computed tomography. Methods: A steepest gradient ascent optimization method is used in conjunction with the JRD and a level set active contour to iteratively evolve a contour to partition an image based on statistical divergence of the intensity histograms. The algorithm is evaluated using PET scans of pharyngolaryngeal squamous cell carcinoma with the corresponding histological reference. The multimodality extension of the algorithm is evaluated using 22 PET/CT scans of patients with lung carcinoma and a physical phantom scanned under varying image quality conditions. Results: The average concordance index (CI) of the JRD segmentation of the PET images was 0.56 with an average classification error of 65%. The segmentation of the lung carcinoma images had a maximum diameter relative error of 63%, 19.5%, and 14.8% when using CT, PET, and combined PET/CT images, respectively. The estimated maximal diameters of the gross tumor volume (GTV) showed a high correlation with the macroscopically determined maximal diameters, with aR{sup 2} value of 0.85 and 0.88 using the PET and PET/CT images, respectively. Results from the physical phantom show that the JRD is more robust to image noise compared to mutual information and region growing. Conclusions: The JRD has shown improved noise tolerance compared to mutual information for the purpose of PET image segmentation. Presented is a flexible framework for multimodal image segmentation that can incorporate a large number of inputs efficiently for IGART.

  14. Characterization of Class A low-level radioactive waste 1986--1990. Volume 6: Appendices G--J

    SciTech Connect (OSTI)

    Dehmel, J.C.; Loomis, D.; Mauro, J. [S. Cohen & Associates, Inc., McLean, VA (United States); Kaplan, M. [Eastern Research Group, Inc., Lexington, MA (United States)

    1994-01-01T23:59:59.000Z

    Under contract to the US Nuclear Regulatory Commission, Office of Nuclear Regulatory Research, the firms of S. Cohen & Associates, Inc. (SC&A) and Eastern Research Group (ERG) have compiled a report that describes the physical, chemical, and radiological properties of Class-A low-level radioactive waste. The report also presents information characterizing various methods and facilities used to treat and dispose non-radioactive waste. A database management program was developed for use in accessing, sorting, analyzing, and displaying the electronic data provided by EG&G. The program was used to present and aggregate data characterizing the radiological, physical, and chemical properties of the waste from descriptions contained in shipping manifests. The data thus retrieved are summarized in tables, histograms, and cumulative distribution curves presenting radionuclide concentration distributions in Class-A waste as a function of waste streams, by category of waste generators, and regions of the United States. The report also provides information characterizing methods and facilities used to treat and dispose non-radioactive waste, including industrial, municipal, and hazardous waste regulated under Subparts C and D of the Resource Conservation and Recovery Act (RCRA). The information includes a list of disposal options, the geographical locations of the processing and disposal facilities, and a description of the characteristics of such processing and disposal facilities. Volume 1 contains the Executive Summary, Volume 2 presents the Class-A waste database, Volume 3 presents the information characterizing non-radioactive waste management practices and facilities, and Volumes 4 through 7 contain Appendices A through P with supporting information.

  15. Implementation of in vivo Dosimetry with Isorad{sup TM} Semiconductor Diodes in Radiotherapy Treatments of the Pelvis

    SciTech Connect (OSTI)

    Rodriguez, Miguel L. [Centro Oncologico Paitilla, Centro Medico Paitilla, Balboa (Panama)], E-mail: miroca_ven@yahoo.com; Abrego, Eladio; Pineda, Amalia [Centro Oncologico Paitilla, Centro Medico Paitilla, Balboa (Panama)

    2008-04-01T23:59:59.000Z

    This report describes the results obtained with the Isorad{sup TM} (Red) semiconductor detectors for implementing an in vivo dosimetry program in patients subject to radiotherapy treatment of the pelvis. Four n-type semiconductor diodes were studied to characterize them for the application. The diode calibration consisted of establishing reading-to-dose conversion factors in reference conditions and a set of correction factors accounting for deviations of the diode response in comparison to that of an ion chamber. Treatments of the pelvis were performed by using an isocentric 'box' technique employing a beam of 18 MV with the shape of the fields defined by a multileaf collimator. The method of Rizzotti-Leunen was used to assess the dose at the isocenter based on measurements of the in vivo dose at the entrance and at the exit of each radiation field. The in vivo dose was evaluated for a population of 80 patients. The diodes exhibit good characteristics for their use in in vivo dosimetry; however, the high attenuation of the beam ({approx}12% at 5.0-cm depth) produced, and some important correction factors, must be taken into account. The correction factors determined, including the source-to-surface factor, were within a range of {+-}4%. The frequency histograms of the relative difference between the expected and measured doses at the entrance, the exit, and the isocenter, have mean values and standard deviations of -0.09% (2.18%), 0.77% (2.73%), and -0.11% (1.76%), respectively. The method implemented has proven to be very useful in the assessment of the in vivo dose in this kind of treatment.

  16. Dosimetric comparison of volumetric modulated Arc therapy, step-and-shoot, and sliding window IMRT for prostate cancer

    SciTech Connect (OSTI)

    Schnell, Erich; De La Fuente Herman, Tania; Young, Julie; Hildebrand, Kim; Algan, Ozer; Syzek, Elizabeth; Herman, Terence; Ahmad, Salahuddin [Department of Radiation Oncology, University of Oklahoma Health Sciences Center 800 N.E. 10th St., OKCC L100, Oklahoma City, OK 73104 (United States)

    2012-10-23T23:59:59.000Z

    This study aims to evaluate treatment plans generated by Step-and-Shoot (SS), Sliding Window (SW) and Volumetric Modulated Arc Therapy (VMAT) in order to assess the differences in dose volume histograms of planning target volume (PTV) and organs at risk (OAR), conformity indices, radiobiological evaluations, and plan quality for prostate cancer cases. Six prostate cancer patients treated in our center were selected for this retrospective study. Treatment plans were generated with Eclipse version 8.9 using 10 MV photon beams. For VMAT, Varian Rapid Arc with 1 or 2 arcs, and for SS and SW IMRT, 7-9 fields were used. Each plan had three PTVs with prescription doses of 81, 59.4, and 45 Gy to prostate, to prostate and lymph nodes, and to pelvis, respectively. Doses to PTV and OAR and the conformal indices (COIN) were compared among three techniques. The equivalent uniform dose (EUD), tumor control probability (TCP) and normal tissue complication probability (NTCP) were calculated and compared. The mean doses to the PTV prostate on average were 83 Gy and the percent differences of mean dose among all techniques were below 0.28. For bladder and rectum, the percent differences of mean dose among all techniques were below 2.2. The COIN did not favour any particular delivery method over the other. The TCP was higher with SS and SW for four patients and higher with VMAT for two patients. The NTCP for the rectum was the lowest with VMAT in five out of the six patients. The results show similar target coverage in general.

  17. Progress Report for UNLV High Pressure Science and Engineering Center

    SciTech Connect (OSTI)

    Mailhiot, C.; Pepper, D.; Lindle, D.; Nicol, M.

    1998-11-20T23:59:59.000Z

    In this report we present results of an in-depth analysis of the SP error densities for 29 satellites. These satellites were divided into three groups--Low Earth Orbit (LEO), Near Circular Orbit (NCO) and Highly Eccentric Orbit (HEO). Included in the first group were those satellites with eccentricities of less than 0.2 and perigees below 450km. The second group included satellites in near circular orbits (eccentricities of less than 0.015) and perigees from 700km to 1500km. The third group consisted of those satellites that were in highly eccentric orbits, namely those with eccentricities greater than 0.2. These satellites have perigees far into the thermosphere. Table 1 contains a summary of the orbit characteristics for the 29 satellites. In our study we attempted to unravel and elucidate the networks of relationships above. The satellite groupings and the report are organized in a way that reflects these efforts. We begin in Section 2 with a summary of the methods used in our analysis. One objective in this study was to establish a baseline for future work in satellite orbit propagators. Section 2 contains descriptions of the SP, truth orbits, and the satellite observation data used to establish this baseline. In the report we show how satellite error densities evolve in time up to thirty-six hours. We present error profiles, error histograms, rms errors and 95/9970 confidence limits for the along-track cross-track, and radial axes of motion for satellites in each of the three groupings. We present results of a regression analysis that establishes a physical model of the error densities. We also link the errors in the various regimes to the quality and quantity of the observational data.

  18. Characterization of Class A low-level radioactive waste 1986--1990. Volume 2: Main report -- Part A

    SciTech Connect (OSTI)

    Dehmel, J.C.; Loomis, D.; Mauro, J. [S. Cohen & Associates, Inc., McLean, VA (United States); Kaplan, M. [Eastern Research Group, Inc., Lexington, MA (United States)

    1994-01-01T23:59:59.000Z

    Under contract to the US Nuclear Regulatory Commission, Office of Nuclear Regulatory Research, the firms of S. Cohen & Associates, Inc. (SC&A) and Eastern Research Group (ERG) have compiled a report that describes the physical, chemical, and radiological properties of Class-A low-level radioactive waste. The report also presents information characterizing various methods and facilities used to treat and dispose non-radioactive waste. A database management program was developed for use in accessing, sorting, analyzing, and displaying the electronic data provided by EG&G. The program was used to present and aggregate data characterizing the radiological, physical, and chemical properties of the, waste from descriptions contained in shipping manifests. The data thus retrieved are summarized in tables, histograms, and cumulative distribution curves presenting radionuclide concentration distributions in Class-A waste as a function of waste streams, by category of waste generators, and regions of the United States. The report also provides information characterizing methods and facilities used to treat and dispose non-radioactive waste, including industrial, municipal, and hazardous waste regulated under Subparts C and D of the Resource Conservation and Recovery Act (RCRA). The information includes a list of disposal options, the geographical locations of the processing and disposal facilities, and a description of the characteristics of such processing and disposal facilities. Volume 1 contains the Executive Summary, Volume 2 presents the Class-A waste database, Volume 3 presents the information characterizing non-radioactive waste management practices and facilities, and Volumes 4 through 7 contain Appendices A through P with supporting information.

  19. Characterization of Class A low-level radioactive waste 1986--1990. Volume 4: Appendices A--E

    SciTech Connect (OSTI)

    Dehmel, J.C.; Loomis, D.; Mauro, J. [S. Cohen & Associates, Inc., McLean, VA (United States); Kaplan, M. [Eastern Research Group, Inc., Lexington, MA (United States)

    1994-01-01T23:59:59.000Z

    Under contract to the US Nuclear Regulatory Commission, Office of Nuclear Regulatory Research, the firms of S. Cohen & Associates, Inc. (SC&A) and Eastern Research Group (ERG) have compiled a report that describes the physical, chemical, and radiological properties of Class-A low-level radioactive waste. The report also presents information characterizing various methods and facilities used to treat and dispose non-radioactive waste. A database management program was developed for use in accessing, sorting, analyzing, and displaying the electronic data provided by EG&G. The program was used to present and aggregate data characterizing the radiological, physical, and chemical properties of the waste from descriptions contained in shipping manifests. The data thus retrieved are summarized in tables, histograms, and cumulative distribution curves presenting radionuclide concentration distributions in Class-A waste as a function of waste streams, by category of waste generators, and regions of the United States. The report also provides information characterizing methods and facilities used to treat and dispose non-radioactive waste, including industrial, municipal, and hazardous waste regulated under Subparts C and D of the Resource Conservation and Recovery Act (RCRA). The information includes a list of disposal options, the geographical locations of the processing and disposal facilities, and a description of the characteristics of such processing and disposal facilities. Volume 1 contains the Executive Summary, Volume 2 presents the Class-A waste database, Volume 3 presents the information characterizing non-radioactive waste management practices and facilities, and Volumes 4 to 7 contain Appendices A to P with supporting information.

  20. Integral radiation dose to normal structures with conformal external beam radiation

    SciTech Connect (OSTI)

    Aoyama, Hidefumi [Department of Human Oncology, University of Wisconsin, Madison, WI (United States) and Department of Radiology, Hokkaido University Graduate School of Medicine, Sapporo (Japan)]. E-mail: hao@radi.med.hokudai.ac.jp; Westerly, David Clark [Department of Medical Physics, University of Wisconsin, Madison, WI (United States); Mackie, Thomas Rockwell [Department of Human Oncology, University of Wisconsin, Madison, WI (United States); Department of Medical Physics, University of Wisconsin, Madison, WI (United States); TomoTherapy Inc., Madison, WI (United States); Olivera, Gustavo H. [Department of Medical Physics, University of Wisconsin, Madison, WI (United States); TomoTherapy Inc., Madison, WI (United States); Bentzen, Soren M. [Department of Human Oncology, University of Wisconsin, Madison, WI (United States); Department of Medical Physics, University of Wisconsin, Madison, WI (United States); Patel, Rakesh R. [Department of Human Oncology, University of Wisconsin, Madison, WI (United States); Jaradat, Hazim [Department of Human Oncology, University of Wisconsin, Madison, WI (United States); Tome, Wolfgang A. [Department of Human Oncology, University of Wisconsin, Madison, WI (United States); Department of Medical Physics, University of Wisconsin, Madison, WI (United States); Ritter, Mark A. [Department of Human Oncology, University of Wisconsin, Madison, WI (United States); Mehta, Minesh P. [Department of Human Oncology, University of Wisconsin, Madison, WI (United States)

    2006-03-01T23:59:59.000Z

    Background: This study was designed to evaluate the integral dose (ID) received by normal tissue from intensity-modulated radiotherapy (IMRT) for prostate cancer. Methods and Materials: Twenty-five radiation treatment plans including IMRT using a conventional linac with both 6 MV (6MV-IMRT) and 20 MV (20MV-IMRT), as well as three-dimensional conformal radiotherapy (3DCRT) using 6 MV (6MV-3DCRT) and 20 MV (20MV-3DCRT) and IMRT using tomotherapy (6MV) (Tomo-IMRT), were created for 5 patients with localized prostate cancer. The ID (mean dose x tissue volume) received by normal tissue (NTID) was calculated from dose-volume histograms. Results: The 6MV-IMRT resulted in 5.0% lower NTID than 6MV-3DCRT; 20 MV beam plans resulted in 7.7%-11.2% lower NTID than 6MV-3DCRT. Tomo-IMRT NTID was comparable to 6MV-IMRT. Compared with 6MV-3DCRT, 6MV-IMRT reduced IDs to the rectal wall and penile bulb by 6.1% and 2.7%, respectively. Tomo-IMRT further reduced these IDs by 11.9% and 16.5%, respectively. The 20 MV did not reduce IDs to those structures. Conclusions: The difference in NTID between 3DCRT and IMRT is small. The 20 MV plans somewhat reduced NTID compared with 6 MV plans. The advantage of tomotherapy over conventional IMRT and 3DCRT for localized prostate cancer was demonstrated in regard to dose sparing of rectal wall and penile bulb while slightly decreasing NTID as compared with 6MV-3DCRT.

  1. Characterization of Class A low-level radioactive waste 1986--1990. Volume 7: Appendices K--P

    SciTech Connect (OSTI)

    Dehmel, J.C.; Loomis, D.; Mauro, J. [S. Cohen & Associates, Inc., McLean, VA (United States); Kaplan, M. [Eastern Research Group, Inc., Lexington, MA (United States)

    1994-01-01T23:59:59.000Z

    Under contract to the US Nuclear Regulatory Commission, Office of Nuclear Regulatory Research, the firms of S. Cohen & Associates, Inc. (SC&A) and Eastern Research Group (ERG) have compiled a report that describes the physical, chemical, and radiological properties of Class-A low-level radioactive waste. The report also presents information characterizing various methods and facilities used to treat and dispose non-radioactive waste. A database management program was developed for use in accessing, sorting, analyzing, and displaying the electronic data provided by EG&G. The program was used to present and aggregate data characterizing the radiological, physical, and chemical properties of the waste from descriptions contained in shipping manifests. The data thus retrieved are summarized in tables, histograms, and cumulative distribution curves presenting radionuclide concentration distributions in Class-A waste as a function of waste streams, by category of waste generators, and regions of the United States. The report also provides information characterizing methods and facilities used to treat and dispose non-radioactive waste, including industrial, municipal, and hazardous waste regulated under Subparts C and D of the Resource Conservation and Recovery Act (RCRA). The information includes a list of disposal options, the geographical locations of the processing and disposal facilities, and a description of the characteristics of such processing and disposal facilities. Volume 1 contains the Executive Summary, Volume 2 presents the Class-A waste database, Volume 3 presents the information characterizing non-radioactive waste management practices and facilities, and Volumes 4 through 7 contain Appendices A through P with supporting information.

  2. Dosimetric Comparison of Manual and Beam Angle Optimization of Gantry Angles in IMRT

    SciTech Connect (OSTI)

    Srivastava, Shiv P. [Department of Radiation Oncology, Reid Hospital and Health Care Services, Richmond, IN (United States); Department of Radiation Oncology, Indiana University School of Medicine, Indianapolis, IN (United States); Das, Indra J., E-mail: idas@iupui.edu [Department of Radiation Oncology, Indiana University School of Medicine, Indianapolis, IN (United States); Kumar, Arvind [Department of Radiation Oncology, Reid Hospital and Health Care Services, Richmond, IN (United States); Johnstone, Peter A.S. [Department of Radiation Oncology, Indiana University School of Medicine, Indianapolis, IN (United States)

    2011-10-01T23:59:59.000Z

    Dosimetric comparison of manual beam angle selection (MBS) and beam angle optimization (BAO) for IMRT plans is investigated retrospectively for 15 head and neck and prostate patients. The head and neck and prostate had planning target volumes (PTVs) ranging between 96.0 and 319.9 cm{sup 3} and 153.6 and 321.3 cm{sup 3}, whereas OAR ranged between 8.3 and 47.8 cm{sup 3} and 68.3 and 469.2 cm{sup 3}, respectively. In MBS, a standard coplanar 7-9 fields equally spaced gantry angles were used. In BAO, the selection of gantry angle was optimized by the algorithm for the same number of beams. The optimization and dose-volume constraints were kept the same for both techniques. Treatment planning was performed on the Eclipse treatment planning system. Our results showed that the dose-volume histogram for PTV are nearly identical in both techniques but BAO provided superior sparing of the organs at risk compared with the MBS. Also, MBS produced statistically significant higher monitor units (MU) and segments than the BAO; 13.1 {+-} 6.6% (p = 0.012) and 10.4 {+-} 13.6% (p = 0.140), and 14.6 {+-} 5.6% (p = 1.003E-5) and 12.6 {+-} 7.4% (p = 0.76E-3) for head and neck and prostate cases, respectively. The reduction in MU translates into the reduction in total body and integral dose. It is concluded that BAO provides advantage over MBS for most intenisty-modulated radiation therapy cases.

  3. Population dose commitments due to radioactive releases from nuclear power plant sites in 1988. Volume 10

    SciTech Connect (OSTI)

    Baker, D.A. [Pacific Northwest Lab., Richland, WA (United States)

    1992-01-01T23:59:59.000Z

    Population radiation dose commitments have been estimated from reported radionuclide releases from commercial power reactors operating during 1988. Fifty-year commitments for a one-year exposure from both liquid and atmospheric releases were calculated for four population groups (infant, child, teen-ager and adult) residing between 2 and 80 km from each of 71 reactor sites. This report tabulates the results of these calculations, showing the dose commitments for both water and airborne pathways for each age group and organ. Also included for each of the sites is a histogram showing the fraction of the total population within 2 to 80 km around each site receiving various average dose commitments from the airborne pathways. The total collective dose commitments (from both liquid and airborne pathways) for each site ranged from a high of 16 person-rem to a low of 0.0011 person-rem for the sites with plants operating throughout the year with an arithmetic mean of 1.1 person-rem. The total population dose for all sites was estimated at 75 person-rem for the 150 million people considered at risk. The site average individual dose commitment from all pathways ranged from a low of 3 {times} 10{sup {minus}7} mrem to a high of 0.02 mrem. No attempt was made in this study to determine the maximum dose commitment received by any one individual from the radionuclides released at any of the sites. However, licensee calculation of doses to the maximally exposed individual at some sites indicated values of up to approximately 100 times average individual doses (on the order of a few millirem per year).

  4. Latest development in seismic texture analysis for subsurface structure, facies, and reservoir characterization: A review

    SciTech Connect (OSTI)

    Gao, Dengliang

    2011-03-01T23:59:59.000Z

    In exploration geology and geophysics, seismic texture is still a developing concept that has not been sufficiently known, although quite a number of different algorithms have been published in the literature. This paper provides a review of the seismic texture concepts and methodologies, focusing on latest developments in seismic amplitude texture analysis, with particular reference to the gray level co-occurrence matrix (GLCM) and the texture model regression (TMR) methods. The GLCM method evaluates spatial arrangements of amplitude samples within an analysis window using a matrix (a two-dimensional histogram) of amplitude co-occurrence. The matrix is then transformed into a suite of texture attributes, such as homogeneity, contrast, and randomness, which provide the basis for seismic facies classification. The TMR method uses a texture model as reference to discriminate among seismic features based on a linear, least-squares regression analysis between the model and the data within an analysis window. By implementing customized texture model schemes, the TMR algorithm has the flexibility to characterize subsurface geology for different purposes. A texture model with a constant phase is effective at enhancing the visibility of seismic structural fabrics, a texture model with a variable phase is helpful for visualizing seismic facies, and a texture model with variable amplitude, frequency, and size is instrumental in calibrating seismic to reservoir properties. Preliminary test case studies in the very recent past have indicated that the latest developments in seismic texture analysis have added to the existing amplitude interpretation theories and methodologies. These and future developments in seismic texture theory and methodologies will hopefully lead to a better understanding of the geologic implications of the seismic texture concept and to an improved geologic interpretation of reflection seismic amplitude

  5. Maximum Entropy Method and Charge Flipping, a Powerful Combination to Visualize the True Nature of Structural Disorder from in situ X-ray Powder Diffraction Data

    SciTech Connect (OSTI)

    Samy, A.; Dinnebier, R; van Smaalen, S; Jansen, M

    2010-01-01T23:59:59.000Z

    In a systematic approach, the ability of the Maximum Entropy Method (MEM) to reconstruct the most probable electron density of highly disordered crystal structures from X-ray powder diffraction data was evaluated. As a case study, the ambient temperature crystal structures of disordered {alpha}-Rb{sub 2}[C{sub 2}O{sub 4}] and {alpha}-Rb{sub 2}[CO{sub 3}] and ordered {delta}-K{sub 2}[C{sub 2}O{sub 4}] were investigated in detail with the aim of revealing the 'true' nature of the apparent disorder. Different combinations of F (based on phased structure factors) and G constraints (based on structure-factor amplitudes) from different sources were applied in MEM calculations. In particular, a new combination of the MEM with the recently developed charge-flipping algorithm with histogram matching for powder diffraction data (pCF) was successfully introduced to avoid the inevitable bias of the phases of the structure-factor amplitudes by the Rietveld model. Completely ab initio electron-density distributions have been obtained with the MEM applied to a combination of structure-factor amplitudes from Le Bail fits with phases derived from pCF. All features of the crystal structures, in particular the disorder of the oxalate and carbonate anions, and the displacements of the cations, are clearly obtained. This approach bears the potential of a fast method of electron-density determination, even for highly disordered materials. All the MEM maps obtained in this work were compared with the MEM map derived from the best Rietveld refined model. In general, the phased observed structure factors obtained from Rietveld refinement (applying F and G constraints) were found to give the closest description of the experimental data and thus lead to the most accurate image of the actual disorder.

  6. Langston University - High Energy Physics

    SciTech Connect (OSTI)

    snow, joel

    2012-08-13T23:59:59.000Z

    This final report is presented by Langston University (LU) for the project entitled "Langston University High Energy Physics" (LUHEP) under the direction of principal investigator (PI) and project director Professor Joel Snow. The project encompassed high energy physics research performed at hadron colliders. The PI is a collaborator on the DZero experiment at Fermi National Accelerator Laboratory in Batavia, IL, USA and the ATLAS experiment at CERN in Geneva, Switzerland and was during the entire project period from April 1, 1999 until May 14, 2012. Both experiments seek to understand the fundamental constituents of the physical universe and the forces that govern their interactions. In 1999 as member of the Online Systems group for Run 2 the PI developed a cross-platform Python-based, Graphical User Interface (GUI) application for monitoring and control of EPICS based devices for control room use. This served as a model for other developers to enhance and build on for further monitoring and control tasks written in Python. Subsequently the PI created and developed a cross-platform C++ GUI utilizing a networked client-server paradigm and based on ROOT, the object oriented analysis framework from CERN. The GUI served as a user interface to the Examine tasks running in the D\\O\\ control room which monitored the status and integrity of data taking for Run 2. The PI developed the histogram server/control interface to the GUI client for the EXAMINE processes. The histogram server was built from the ROOT framework and was integrated into the D\\O\\ framework used for online monitoring programs and offline analysis. The PI developed the first implementation of displaying histograms dynamically generated by ROOT in a Web Browser. The PI's work resulted in several talks and papers at international conferences and workshops. The PI established computing software infrastructure at LU and U. Oklahoma (OU) to do analysis of DZero production data and produce simulation data for the experiment. Eventually this included the FNAL SAM data grid system, the SAMGrid (SG) infrastructure, and the Open Science Grid software stacks for computing and storage elements. At the end of 2003 the PI took on the role of global Monte Carlo production coordinator for the DZero experiment. In January of 2004 the PI started working with the SAMGrid development team to help debug, deploy, and integrate SAMGrid with DZero Monte Carlo production. The PI installed and configured SG execution and client sites at LUHEP and OUHEP, and a SG scheduler site at LUHEP. The PI developed a python based GUI (DAJ) that acts as a front end for job submission to SAMGrid. The GUI interfaces to the DZero Mone Carlo (MC) request system that uses SAM to manage MC requests by the physics analysis groups. DAJ significantly simplified SG job submission and was deployed in DZero in an effort to increase the user base of SG. The following year was the advent of SAMGrid job submission to the Open Science Grid (OSG) and LHC Computing Grid (LCG) through a forwarding mechanism. The PI oversaw the integration of these grids into the existing production infrastructure. The PI developed an automatic MC (Automc) request processing system capable of operating without user intervention (other than getting grid credentials), and able to submit to any number of sites on various grids. The system manages production at all but 2 sites. The system was deployed at Fermilab and remains operating there today. The PI's work in distributed computing resulted in several talks at international conferences. UTA, OU, and LU were chosen as the collaborating institutions that form the Southwest Tier 2 Center (SWT2) for ATLAS. During the project period the PI contributed to the online and offline software infrastructure through his work with the Run 2 online group, and played a major role in Monte Carlo production for DZero. During the part of the project period in which the PI served as MC production coordinator MC production increased very significantly. In the first year of the PI's tenure as production coor

  7. PROBABILISTIC HAZARD ASSESSMENT FOR TORNADOES, STRAIGHT-LINE WIND, AND EXTREME PRECIPITATION AT THE SAVANNAH RIVER SITE

    SciTech Connect (OSTI)

    Werth, D.; (NOEMAIL), A.; Shine, G.

    2013-12-04T23:59:59.000Z

    Recent data sets for three meteorological phenomena with the potential to inflict damage on SRS facilities - tornadoes, straight winds, and heavy precipitation - are analyzed using appropriate statistical techniques to estimate occurrence probabilities for these events in the future. Summaries of the results for DOE-mandated return periods and comparisons to similar calculations performed in 1998 by Weber, et al., are given. Using tornado statistics for the states of Georgia and South Carolina, we calculated the probability per year of any location within a 2? square area surrounding SRS being struck by a tornado (the ‘strike’ probability) and the probability that any point will experience winds above set thresholds. The strike probability was calculated to be 1.15E-3 (1 chance in 870) per year and wind speeds for DOE mandated return periods of 50,000 years, 125,000 years, and 1E+7 years (USDOE, 2012) were estimated to be 136 mph, 151 mph and 221 mph, respectively. In 1998 the strike probability for SRS was estimated to be 3.53 E-4 and the return period wind speeds were 148 mph every 50,000 years and 180 mph every 125,000 years. A 1E+7 year tornado wind speed was not calculated in 1998; however a 3E+6 year wind speed was 260 mph. The lower wind speeds resulting from this most recent analysis are largely due to new data since 1998, and to a lesser degree differences in the models used. By contrast, default tornado wind speeds taken from ANSI/ANS-2.3-2011 are somewhat higher: 161 mph for return periods of 50,000 years, 173 mph every 125,000 years, and 230 mph every 1E+7 years (ANS, 2011). Although the ANS model and the SRS models are very similar, the region defined in ANS 2.3 that encompasses the SRS also includes areas of the Great Plains and lower Midwest, regions with much higher occurrence frequencies of strong tornadoes. The SRS straight wind values associated with various return periods were calculated by fitting existing wind data to a Gumbel distribution, and extrapolating the values for any return period from the tail of that function. For the DOE mandated return periods, we expect straight winds of 123 mph every 2500 years, and 132mph every 6250 years at any point within the SRS. These values are similar to those from the W98 report (which also used the Gumbel distribution for wind speeds) which gave wind speeds of 115mph and 122 mph for return periods of 2500 years and 6250 years, respectively. For extreme precipitation accumulation periods, we compared the fits of three different theoretical extreme-value distributions, and in the end decided to maintain the use of the Gumbel distribution for each period. The DOE mandated 6-hr accumulated rainfall for return periods of 2500 years and 6250 years was estimated as 7.8 inches and 8.4 inches, respectively. For the 24- hr rainfall return periods of 10,000 years and 25,000 years, total rainfall estimates were 10.4 inches and 11.1 inches, respectively. These values are substantially lower than comparable values provided in the W98 report. This is largely a consequence of the W98 use of a different extreme value distribution with its corresponding higher extreme probabilities.

  8. Extended (5-year) Outcomes of Accelerated Partial Breast Irradiation Using MammoSite Balloon Brachytherapy: Patterns of Failure, Patient Selection, and Dosimetric Correlates for Late Toxicity

    SciTech Connect (OSTI)

    Vargo, John A.; Verma, Vivek; Kim, Hayeon; Kalash, Ronny; Heron, Dwight E.; Johnson, Ronald; Beriwal, Sushil, E-mail: beriwals@upmc.edu

    2014-02-01T23:59:59.000Z

    Purpose: Accelerated partial breast irradiation (APBI) with balloon and catheter-based brachytherapy has gained increasing popularity in recent years and is the subject of ongoing phase III trials. Initial data suggest promising local control and cosmetic results in appropriately selected patients. Long-term data continue to evolve but are limited outside of the context of the American Society of Breast Surgeons Registry Trial. Methods and Materials: A retrospective review of 157 patients completing APBI after breast-conserving surgery and axillary staging via high-dose-rate {sup 192}Ir brachytherapy from June 2002 to December 2007 was made. APBI was delivered with a single-lumen MammoSite balloon-based applicator to a median dose of 34 Gy in 10 fractions over a 5-day period. Tumor coverage and critical organ dosimetry were retrospectively collected on the basis of computed tomography completed for conformance and symmetry. Results: At a median follow-up time of 5.5 years (range, 0-10.0 years), the 5-year and 7-year actuarial incidences of ipsilateral breast control were 98%/98%, of nodal control 99%/98%, and of distant control 99%/99%, respectively. The crude rate of ipsilateral breast recurrence was 2.5% (n=4); of nodal failure, 1.9% (n=3); and of distant failure, 0.6% (n=1). The 5-year and 7-year actuarial overall survival rates were 89%/86%, with breast cancer–specific survival of 100%/99%, respectively. Good to excellent cosmetic outcomes were achieved in 93.4% of patients. Telangiectasia developed in 27% of patients, with 1-year, 3-year, and 5-year actuarial incidence of 7%/24%/33%; skin dose >100% significantly predicted for the development of telangiectasia (50% vs 14%, P<.0001). Conclusions: Long-term single-institution outcomes suggest excellent tumor control, breast cosmesis, and minimal late toxicity. Skin toxicity is a function of skin dose, which may be ameliorated with dosimetric optimization afforded by newer multicatheter brachytherapy applicators and a more rigorous skin dose constraint of ?100%.

  9. TFE Verification Program. Semiannual report for the period ending March 31, 1993

    SciTech Connect (OSTI)

    Not Available

    1993-05-01T23:59:59.000Z

    The objective of the semiannual progress report is to summarize the technical results obtained during the latest reporting period. The information presented herein will include evaluated test data, design evaluations, the results of analyses and the significance of results. The program objective is to demonstrate the technology readiness of a TFE (thermionic fuel element) suitable for use as the basic element in a thermionic reactor with electric power output in the 0.5 to 5.0 MW(e) range, and a full-power life of 7 years. The TFE Verification Program builds directly on the technology and data base developed in the 1960s and early 1970s in an AEC/NASA program, and in the SP-100 program conducted in 1983, 1984 and 1985. In the SP-100 program, the attractive features of thermionic power conversion technology were recognized but concern was expressed over the lack of fast reactor irradiation data. The TFE Verification Program addresses this concern.

  10. TFE Verification Program

    SciTech Connect (OSTI)

    Not Available

    1993-05-01T23:59:59.000Z

    The objective of the semiannual progress report is to summarize the technical results obtained during the latest reporting period. The information presented herein will include evaluated test data, design evaluations, the results of analyses and the significance of results. The program objective is to demonstrate the technology readiness of a TFE (thermionic fuel element) suitable for use as the basic element in a thermionic reactor with electric power output in the 0.5 to 5.0 MW(e) range, and a full-power life of 7 years. The TFE Verification Program builds directly on the technology and data base developed in the 1960s and early 1970s in an AEC/NASA program, and in the SP-100 program conducted in 1983, 1984 and 1985. In the SP-100 program, the attractive features of thermionic power conversion technology were recognized but concern was expressed over the lack of fast reactor irradiation data. The TFE Verification Program addresses this concern.

  11. TRU partnership: Overview of technical challenges and initiatives

    SciTech Connect (OSTI)

    Moore, J.W. [Oak Ridge National Lab., TN (United States); Martin, M.R.; Mullin, R.J. [EG and G Idaho, Inc., Idaho Falls, ID (United States); Ball, D.E. [Westinghouse Hanford Co., Richland, WA (United States); Stewart, D.E. [Westinghouse Savannah River Co., Aiken, SC (United States)

    1994-03-01T23:59:59.000Z

    The Waste Isolation Pilot Plant (WIPP) has been constructed in a geologic salt deposit in Carlsbad, New Mexico. Current plans have the WIPP scheduled to begin permanent emplacement of TRU waste starting in approximately 2000 after completion of a 5-7 year test phase that is scheduled to begin in 1994. The WIPP has prepared a waste acceptance criteria (WAC) that establishes requirements that must be met by waste packages intended for disposal at WIPP. In addition there are other existing criteria (e.g. DOE General Design Criteria 6430.lA), regulations, procedures, guidelines and safety concerns (e.g. ALARA), regarding designing, building and operating radiological waste handling/processing facilities. All of these, along with the desire to minimize each projects total cost, encourage and in some cases dictate the use of new, developing technologies and other innovative technologies and operating philosophies. In the summer of 1990 the TRU Partnership was formed comprising several of the DOE TRU waste generator and storage/disposal sites. This partnership meets approximately quarterly to present the status of each site`s projects and has resulted in the establishment of a list of technical/development needs/challenges and initiatives. The initiatives are discussed in this report.

  12. 1988 Wet deposition temporal and spatial patterns in North America

    SciTech Connect (OSTI)

    Simpson, J.C.; Olsen, A.R.; Bittner, E.A.

    1992-03-01T23:59:59.000Z

    The focus of this report is on North American wet deposition temporal patterns from 1979 to 1988 and spatial patterns for 1988. It is the third in a series of reports that investigate the patterns of annual precipitation-weighted average concentration and annual deposition for nine ion species: hydrogen, sulfate, nitrate, ammonium, calcium, chloride, sodium, potassium, and magnesium. Mosaic maps, based on surface estimation using kriging, display concentration and deposition spatial patterns of pH, hydrogen, sulfate, nitrate, ammonium, and calcium ion species for 1988 annual, winter, and summer periods. Temporal pattern analyses use a subset of 35 sites over a 10-year (1979--1988) period and an expanded subset of 137 sites, with greater spatial coverage, over a 7-year (1982--1988) period. The 10-year period represents the longest period with wet deposition monitoring data available that has a sufficient number of sites with data of known quality to allow a descriptive summary of annual temporal patterns. Sen's median trend estimate and Kendall's seasonal tau (KST) test are calculated for each ion species concentration and deposition at each site in both subsets.

  13. 1988 Wet deposition temporal and spatial patterns in North America

    SciTech Connect (OSTI)

    Simpson, J.C.; Olsen, A.R.; Bittner, E.A.

    1992-03-01T23:59:59.000Z

    The focus of this report is on North American wet deposition temporal patterns from 1979 to 1988 and spatial patterns for 1988. It is the third in a series of reports that investigate the patterns of annual precipitation-weighted average concentration and annual deposition for nine ion species: hydrogen, sulfate, nitrate, ammonium, calcium, chloride, sodium, potassium, and magnesium. Mosaic maps, based on surface estimation using kriging, display concentration and deposition spatial patterns of pH, hydrogen, sulfate, nitrate, ammonium, and calcium ion species for 1988 annual, winter, and summer periods. Temporal pattern analyses use a subset of 35 sites over a 10-year (1979--1988) period and an expanded subset of 137 sites, with greater spatial coverage, over a 7-year (1982--1988) period. The 10-year period represents the longest period with wet deposition monitoring data available that has a sufficient number of sites with data of known quality to allow a descriptive summary of annual temporal patterns. Sen`s median trend estimate and Kendall`s seasonal tau (KST) test are calculated for each ion species concentration and deposition at each site in both subsets.

  14. Chemical composition and origin of nebulae around Luminous Blue Variables

    E-Print Network [OSTI]

    Lamers, Henny J G L M; Panagia, N; Smith, L J; Langer, N; Lamers, Henny J.G.L.M.; Nota, Antonella; Panagia, Nino; Smith, Linda J.; Langer, Norbert

    2001-01-01T23:59:59.000Z

    We use the analysis of the heavy element abundances (C, N, O, S) in circumstellar nebulae around Luminous Blue Variables to infer the evolutionary phase in which the material has been ejected. (1) We discuss the different effects that may have changed the gas composition of the nebula since it was ejected (2) We calculate the expected abundance changes at the stellar surface due to envelope convection in the red supergiant phase. If the observed LBV nebulae are ejected during the RSG phase, the abundances of the LBV nebulae require a significantly smaller amount of mass to be lost than assumed in evolutionary models. (3) We calculate the changes in the surface composition during the main sequence phase by rotation induced mixing. If the nebulae are ejected at the end of the MS-phase, the abundances in LBV nebulae are compatible with mixing times between 5 x 10^6 and 1 x 10^7 years. The existence of ON stars supports this scenario. (4) The predicted He/H ratio in the nebulae are significantly smaller than the ...

  15. AGN Physics from QSO Clustering

    E-Print Network [OSTI]

    Scott Croom; Brian Boyle; Tom Shanks; Phil Outram; Robert Smith; Lance Miller; Nicola Loaring; Suzanne Kenyon; Warrick Couch

    2003-10-20T23:59:59.000Z

    We review the current status of QSO clustering measurements, particular with respect to their relevance in understanding AGN physics. Measurements based on the 2dF QSO Redshift Survey (2QZ) find a scale length for QSO clustering of s_0=5.76(+0.17-0.27) h-1 Mpc at a redshift ~1.5, very similar to low redshift galaxies. There is no evidence of evolution in the clustering of QSOs from z~0.5 to z~2.2. This lack of evolution and low clustering amplitude suggests a short life time for AGN activity of the order ~10^6-10^7 years. Large surveys such at the 2QZ and SDSS also allow the the study of QSO environments in 3D for the first time (at least at low redshift), early results from this work seem to show no difference between the environments of QSOs and normal galaxies. Future studies e.g. measuring clustering as a function of black hole mass, and deep QSO surveys should provide further insight into the formation and evolution of AGN.

  16. SOLAR ROTATION RATE DURING THE CYCLE 24 MINIMUM IN ACTIVITY

    SciTech Connect (OSTI)

    Antia, H. M. [Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai 400005 (India); Basu, Sarbani, E-mail: antia@tifr.res.i, E-mail: sarbani.basu@yale.ed [Department of Astronomy, Yale University, P.O. Box 208101, New Haven CT 06520-8101 (United States)

    2010-09-01T23:59:59.000Z

    The minimum of solar cycle 24 is significantly different from most other minima in terms of its duration as well as its abnormally low levels of activity. Using available helioseismic data that cover epochs from the minimum of cycle 23 to now, we study the differences in the nature of the solar rotation between the minima of cycles 23 and 24. We find that there are significant differences between the rotation rates during the two minima. There are differences in the zonal-flow pattern too. We find that the band of fast rotating region close to the equator bifurcated around 2005 and recombined by 2008. This behavior is different from that during the cycle 23 minimum. By autocorrelating the zonal-flow pattern with a time shift, we find that in terms of solar dynamics, solar cycle 23 lasted for a period of 11.7 years, consistent with the result of Howe et al. (2009). The autocorrelation coefficient also confirms that the zonal-flow pattern penetrates through the convection zone.

  17. Economic development through biomass system integration: Summary report

    SciTech Connect (OSTI)

    DeLong, M.M. [Northern States Power Co., Minneapolis, MN (United States)

    1995-10-01T23:59:59.000Z

    Alfalfa is a well-known and widely-planted crop that offers environmental and soil conservation advantages when grown as a 4-year segment in a 7-year rotation with corn and soybeans. Alfalfa fixes nitrogen from the air, thereby enhancing soil nitrogen and decreasing the need for manufactured nitrogen fertilizer. With alfalfa yields of 4 dry tons per acre per year and the alfalfa leaf fraction sold as a high-value animal feed the remaining alfalfa stem fraction can be economically viable fuel feedstock for a gasifier combined cycle power plant. This report is a feasibility study for an integrated biomass power system, where an energy crop (alfalfa) is the feedstock for a processing plant and a power power plant (integrated gasification combined cycle) in a way that benefits the facility owners. The sale of an animal feed co-product and electricity both help cover the production cost of alfalfa and the feedstock processing cost, thereby requiring neither the electricity or leaf meal to carry the total cost. The power plant provides an important continous demand for the feedstock and results in continous supply of leaf product to provide a reliable supply needed for the leaf meal product.

  18. Probing Neutrino Oscillation Parameters using High Power Superbeam from ESS

    E-Print Network [OSTI]

    Agarwalla, Sanjib Kumar; Prakash, Suprabh

    2014-01-01T23:59:59.000Z

    A high-power neutrino superbeam experiment at the ESS facility has been proposed such that the source-detector distance falls at the second oscillation maximum, giving very good sensitivity to the measurement of CP violation. In this work, we explore the comparative physics reach of the experiment in terms of leptonic CP-violation, precision on atmospheric parameters, non-maximal theta23, and its octant for a variety of choices for the baselines. We also vary the neutrino vs. the anti-neutrino running time for the beam, and study its impact on the physics goals of the experiment. We find that for the determination of CP violation, 540 km baseline with 7 years of neutrino and 3 years of anti-neutrino (7nu+3nubar) run-plan performs the best and one expects a 4sigma sensitivity to CP violation for 59% of true values of deltaCP. The projected reach for the 200 km baseline with 7nu+3nubar run-plan is somewhat worse with 4sigma sensitivity for 51% of true values of deltaCP. On the other hand, for the discovery of a...

  19. Probing bulk viscous matter-dominated models with Gamma-ray bursts

    E-Print Network [OSTI]

    A. Montiel; N. Bretón

    2011-07-01T23:59:59.000Z

    In this paper we extend the range of consistency of a constant bulk viscosity model to redshifts up to $z\\sim 8.1$. In this model the dark sector of the cosmic substratum is a viscous fluid with pressure $p= -\\zeta \\theta$, where $\\theta$ is the fluid-expansion scalar and $\\zeta$ is the coefficient of bulk viscosity. Using the sample of 59 high-redshift GRBs reported by Wei (2010), we calibrate GRBs at low redshifts with the Union 2 sample of SNe Ia, avoiding then the circularity problem. Testing the constant bulk viscosity model with GRBs we found the best fit for the viscosity parameter $\\tilde{\\zeta}$ in the range $0<\\tilde{\\zeta}<3$, being so consistent with previous probes; we also determined the deceleration parameter $q_0$ and the redshift of transition to accelerated expansion. Besides we present an updated analysis of the model with CMB5-year data and CMB7-year data, as well as with the baryon acoustic peak BAO. From the statistics with CMB it turns out that the model does not describe in a feasible way the far far epoch of recombination of the universe, but is in very good concordance for epochs as far as $z\\sim 8.1$ till present.

  20. Testing the interaction model with cosmological data and gamma-ray bursts

    E-Print Network [OSTI]

    Yu Pan; Shuo Cao; Yungui Gong; Kai Liao; Zong-Hong Zhu

    2012-11-01T23:59:59.000Z

    We use the new gamma-ray bursts (GRBs) data, combined with the baryon acoustic oscillation(BAO) observation from the spectroscopic Sloan Digital Sky Survey (SDSS) data release, the newly obtained $A$ parameter at $z=0.6$ from the WiggleZ Dark Energy Survey, the cosmic microwave background (CMB) observations from the 7-Year Wilkinson Microwave Anisotropy Probe (WMAP7) results, and the type Ia supernovae (SNeIa) from Union2 set, to constrain a phenomenological model describing possible interactions between dark energy and dark matter, which was proposed to alleviate the coincidence problem of the standard $\\Lambda$CDM model. By using the Markov Chain Monte Carlo (MCMC) method, we obtain the marginalized $1\\sigma$ constraints $\\Omega_{m}=0.2886\\pm{0.0135}$, $r_m=-0.0047\\pm{0.0046}$, and $w_X=-1.0658\\pm{0.0564}$. We also consider other combinations of these data for comparison. These results show that: (1) the energy of dark matter is slightly transferring to that of dark energy; (2) even though the GRBs+BAO+CMB data present less stringent constraints than SNe+BAO+CMB data do, the GRBs can help eliminate the degeneracies among parameters.

  1. Information architecture. Volume 4: Vision

    SciTech Connect (OSTI)

    NONE

    1998-03-01T23:59:59.000Z

    The Vision document marks the transition from definition to implementation of the Department of Energy (DOE) Information Architecture Program. A description of the possibilities for the future, supported by actual experience with a process model and tool set, points toward implementation options. The directions for future information technology investments are discussed. Practical examples of how technology answers the business and information needs of the organization through coordinated and meshed data, applications, and technology architectures are related. This document is the fourth and final volume in the planned series for defining and exhibiting the DOE information architecture. The targeted scope of this document includes DOE Program Offices, field sites, contractor-operated facilities, and laboratories. This document paints a picture of how, over the next 7 years, technology may be implemented, dramatically improving the ways business is conducted at DOE. While technology is mentioned throughout this document, the vision is not about technology. The vision concerns the transition afforded by technology and the process steps to be completed to ensure alignment with business needs. This goal can be met if those directing the changing business and mission-support processes understand the capabilities afforded by architectural processes.

  2. Accounting strategy of tritium inventory in the heavy water detritiation pilot plant from ICIT Rm. Valcea

    SciTech Connect (OSTI)

    Bidica, N.; Stefanescu, I. [Inst. of Cryogenics and Isotopes Technologies, Uzinei Str. No. 4, Rm. Valcea (Romania); Cristescu, I. [TLK, Forschungszentrum Karlsruhe, Postfach 3640, D76021 Karlsruhe (Germany); Bornea, A.; Zamfirache, M.; Lazar, A.; Vasut, F.; Pearsica, C.; Stefan, I. [Inst. of Cryogenics and Isotopes Technologies, Uzinei Str. No. 4, Rm. Valcea (Romania); Prisecaru, I.; Sindilar, G. [Univ. Politehnica of Bucharest, Splaiul Independentei 313, Bucharest (Romania)

    2008-07-15T23:59:59.000Z

    In this paper we present a methodology for determination of tritium inventory in a tritium removal facility. The method proposed is based on the developing of computing models for accountancy of the mobile tritium inventory in the separation processes, of the stored tritium and of the trapped tritium inventory in the structure of the process system components. The configuration of the detritiation process is a combination of isotope catalytic exchange between water and hydrogen (LPCE) and the cryogenic distillation of hydrogen isotopes (CD). The computing model for tritium inventory in the LPCE process and the CD process will be developed basing on mass transfer coefficients in catalytic isotope exchange reactions and in dual-phase system (liquid-vapour) of hydrogen isotopes distillation process. Accounting of tritium inventory stored in metallic hydride will be based on in-bed calorimetry. Estimation of the trapped tritium inventory can be made by subtraction of the mobile and stored tritium inventories from the global tritium inventory of the plant area. Determinations of the global tritium inventory of the plant area will be made on a regular basis by measuring any tritium quantity entering or leaving the plant area. This methodology is intended to be applied to the Heavy Water Detritiation Pilot Plant from ICIT Rm. Valcea (Romania) and to the Cernavoda Tritium Removal Facility (which will be built in the next 5-7 years). (authors)

  3. Lateral Distribution for Aligned Events in Muon Groups Deep Underground

    E-Print Network [OSTI]

    A. L. Tsyabuk; R. A. Mukhamedshin; Yu. V. Stenkin

    2007-01-09T23:59:59.000Z

    The paper concerns the so-called aligned events observed in cosmic rays. The phenomenon of the alignment of the most energetic subcores of gamma-ray--hadron ($\\gamma-h$) families (particles of the highest energies in the central EAS core) was firstly found in the "Pamir" emulsion chamber experiment and related to a coplanar particle production at $E_0>10^{16}$ eV. Here a separation distribution (distances between pairs of muons) for aligned events has been analyzed throughout muon groups measured by Baksan Underground Scintillation Telescope (BUST) for threshold energies $0.85 \\div 3.2$ TeV during a period of 7.7 years. Only muon groups of multiplicity $m\\geq 4$ with inclined trajectories for an interval of zenith angles $50^\\circ - 60^\\circ$ were selected for the analysis. The analysis has revealed that the distribution complies with the exponential law. Meanwhile the distributions become steeper with the increase of threshold energy. There has been no difference between the lateral distribution of all the groups and the distribution of the aligned groups.

  4. R Coronae Borealis stars in the Galactic Bulge discovered by EROS-2

    E-Print Network [OSTI]

    Tisserand, P; Wood, P R; Lesquoy, E; Beaulieu, J P; Milsztajn, A; Hamadache, C; Afonso, C; Albert, J N; Andersen, J; Ansari, R; Aubourg, E; Bareyre, P; Charlot, X; Coutures, C; Ferlet, R; Fouqué, P; Glicenstein, J F; Goldman, B; Gould, A; Gros, M; Haïssinski, J; De Kat, J; Guillou, L Le; Loup, C; Magneville, C; Maurice, E; Maury, A; Moniez, M; Palanque-Delabrouille, Nathalie; Perdereau, O; Rahal, Y; Rich, J; Spiro, M; Vidal-Madjar, A; Zylberajch, S

    2008-01-01T23:59:59.000Z

    Rare types of variable star may give unique insight into short-lived stages of stellar evolution. The systematic monitoring of millions of stars and advanced light curve analysis techniques of microlensing surveys make them ideal for discovering also such rare variable stars. One example is the R Coronae Borealis (RCB) stars, a rare type of evolved carbon-rich supergiant. We have conducted a systematic search of the EROS-2 database for the Galactic catalogue Bulge and spiral arms to find Galactic RCB stars. The light curves of $\\sim$100 million stars, monitored for 6.7 years (from July 1996 to February 2003), have been analysed to search for the main signature of RCB stars, large and rapid drops in luminosity. Follow-up spectroscopy has been used to confirm the photometric candidates. We have discovered 14 new RCB stars, all in the direction of the Galactic Bulge, bringing the total number of confirmed Galactic RCB stars to about 51. After reddening correction, the colours and absolute magnitudes of at least ...

  5. Limits on the Macho Content of the Galactic Halo from the EROS-2 Survey of the Magellanic Clouds

    E-Print Network [OSTI]

    Tisserand, P; Afonso, C; Albert, J N; Andersen, J; Ansari, R; Aubourg, E; Bareyre, P; Beaulieu, J P; Charlot, X; Coutures, C; Ferlet, R; Fouqué, P; Glicenstein, J F; Goldman, B; Gould, A; Graff, D; Gros, M; Haïssinski, J; Hamadache, C; De Kat, J; Lasserre, T; Lesquoy, E; Loup, C; Magneville, C; Marquette, J B; Maurice, E; Maury, A; Milsztajn, A; Moniez, M; Palanque-Delabrouille, Nathalie; Perdereau, O; Rahal, Y R; Rich, J; Spiro, M; Vidal-Madjar, A; Vigroux, L; Zylberajch, S

    2006-01-01T23:59:59.000Z

    The EROS-2 project was designed to test the hypothesis that massive compact halo objects (the so-called ``machos'') could be a major component of the dark matter halo of the Milky Way galaxy. To this end, EROS-2 monitored millions of stars in the Magellanic clouds for microlensing events caused by such objects. About $33\\times10^6$ Magellanic stars were observed over a period of 6.7 years. Unlike all previous studies of Magellanic microlensing, we use only a subsample of $7\\times10^6$ bright stars. This strategy minimizes backgrounds due to variable stars and ensures accurate determination of lensing parameters by minimizing source confusion (blending). Using this sample of bright stars, only one candidate event was found, whereas $\\sim42$ events would have been expected if the Halo were entirely populated by objects of mass $M\\sim0.4M_{\\odot}$. Combined with the results of EROS-1, this implies that the optical depth toward the Large Magellanic Cloud (\\object{LMC}) due to such lenses is $\\tau<0.36\\times10^...

  6. Technical Support Document: 50% Energy Savings for Small Office Buildings

    SciTech Connect (OSTI)

    Thornton, Brian A.; Wang, Weimin; Huang, Yunzhi; Lane, Michael D.; Liu, Bing

    2010-04-30T23:59:59.000Z

    The Technical Support Document (TSD) for 50% energy savings in small office buildings documents the analysis and results for a recommended package of energy efficiency measures (EEMs) referred to as the advanced EEMs. These are changes to a building design that will reduce energy usage. The package of advanced EEMs achieves a minimum of 50% energy savings and a construction area weighted average energy savings of 56.6% over the ANSI/ASHRAE/IESNA Standard 90.1-2004 for 16 cities which represent the full range of climate zones in the United States. The 50% goal is for site energy usage reduction. The weighted average is based on data on the building area of construction in the various climate locations. Cost-effectiveness of the EEMs is determined showing an average simple payback of 6.7 years for all 16 climate locations. An alternative set of results is provided which includes a variable air volume HVAC system that achieves at least 50% energy savings in 7 of the 16 climate zones with a construction area weighted average savings of 48.5%. Other packages of EEMs may also achieve 50% energy savings; this report does not consider all alternatives but rather presents at least one way to reach the goal. Design teams using this TSD should follow an integrated design approach and utilize additional analysis to evaluate the specific conditions of a project.

  7. Safety Evaluation Report for the Claiborne Enrichment Center, Homer, Louisiana (Docket No. 70-3070)

    SciTech Connect (OSTI)

    Not Available

    1994-01-01T23:59:59.000Z

    This report documents the US Nuclear Regulatory Commission (NRC) staff review and safety evaluation of the Louisiana Energy Services, L.P. (LES, the applicant) application for a license to possess and use byproduct, source, and special nuclear material and to enrich natural uranium to a maximum of 5 percent U-235 by the gas centrifuge process. The plant, to be known as the Claiborne Enrichment Center (CEC), would be constructed near the town of Homer in Claiborne Parish, Louisiana. At full production in a given year, the plant will receive approximately 4,700 tonnes of feed UF{sub 6} and produce 870 tonnes of low-enriched UF{sub 6}, and 3,830 tonnes of depleted UF{sub 6} tails. Facility construction, operation, and decommissioning are expected to last 5, 30, and 7 years, respectively. The objective of the review is to evaluate the potential adverse impacts of operation of the facility on worker and public health and safety under both normal operating and accident conditions. The review also considers the management organization, administrative programs, and financial qualifications provided to assure safe design and operation of the facility. The NRC staff concludes that the applicant`s descriptions, specifications, and analyses provide an adequate basis for safety review of facility operations and that construction and operation of the facility does not pose an undue risk to public health and safety.

  8. Air Distribution Retrofit Strategies for Affordable Housing

    SciTech Connect (OSTI)

    Dentz, J.; Conlin, F.; Holloway, P.; Podorson, D.; Varshney, K.

    2014-03-01T23:59:59.000Z

    In multifamily and attached buildings, traditional duct sealing methods are often impractical or costly and disruptive because of the difficulty in accessing leakage sites. In this project, two retrofit duct sealing techniques -- manually-applied sealants and injecting a spray sealant, were implemented in several low-rise multi-unit buildings. An analysis on the cost and performance of the two methods are presented. Each method was used in twenty housing units: approximately half of each group of units are single story and the remainder two-story. Results show that duct leakage to the outside was reduced by an average of 59% through the use of manual methods, and by 90% in the units where the injected spray sealant was used. It was found that 73% of the leakage reduction in homes that were treated with injected spray sealant was attributable to the manual sealing done at boots, returns and the air handler. The cost of manually-applying sealant ranged from $275 to $511 per unit and for the injected spray sealant the cost was $700 per unit. Modeling suggests a simple payback of 2.2 years for manual sealing and 4.7 years for the injected spray sealant system. Utility bills were collected for one year before and after the retrofits. Utility bill analysis shows 14% and 16% energy savings using injected spray sealant system and hand sealing procedure respectively in heating season whereas in cooling season, energy savings using injected spray sealant system and hand sealing were both 16%.

  9. Radiative ages in a representative sample of low luminosity radio galaxies

    E-Print Network [OSTI]

    P. Parma; M. Murgia; R. Morganti; A. Capetti; H. R. de Ruiter; R. Fanti

    1998-12-22T23:59:59.000Z

    Two frequency observations, mainly at 1.4 and 5 GHz from the VLA, have been used to study spectral variations along the lobes of some nearby low luminosity radio galaxies that constitute a representative sample selected from the B2 catalogue. The variations of the spectral index have been interpreted as being due to synchrotron and inverse Compton losses and characteristic spectral ages are deduced for the relativistic electrons. The radiative ages are in the range of several 10^7 years. These ages correlate well with the source sizes. They also appear to be consistent with dynamical ages determined from ram-pressure arguments, if we make reasonable assumptions about the ambient gas density and allow for very moderate deviations from the equipartition conditions. There appears to be a significant difference between the radiative ages of sources in our sample and those of more powerful 3CR radio sources. We briefly discuss the possibility of re-acceleration processes and indicate some objects where these may occur.

  10. Management of Renal Tumors by Image-Guided Radiofrequency Ablation: Experience in 105 Tumors

    SciTech Connect (OSTI)

    Breen, David J., E-mail: david.breen@suht.swest.nhs.uk; Rutherford, Elizabeth E.; Stedman, Brian [Southampton University Hospitals NHS Trust, Department of Radiology (United Kingdom); Roy-Choudhury, Shuvro H.; Cast, James E. I. [Hull and East Yorkshire NHS Trust, Department of Radiology (United Kingdom); Hayes, Matthew C.; Smart, Christopher J. [Southampton University Hospitals NHS Trust, Department of Urology (United Kingdom)

    2007-09-15T23:59:59.000Z

    Aims. In this article we present our experience with radiofrequency ablation (RFA) in the treatment of 105 renal tumors. Materials and Methods. RFA was performed on 105 renal tumors in 97 patients, with a mean tumor size of 32 mm (11-68 mm). The mean patient age was 71.7 years (range, 36-89 years). The ablations were carried out under ultrasound (n = 43) or CT (n = 62) guidance. Imaging follow-up was by contrast-enhanced CT within 10 days and then at 6-monthly intervals. Multivariate analysis was performed to determine variables associated with procedural outcome. Results. Eighty-three tumors were completely treated at a single sitting (79%). Twelve of the remaining tumors were successfully re-treated and a clinical decision was made not to re-treat seven patients. A patient with a small residual crescent of tumor is under follow-up and may require further treatment. In another patient, re-treatment was abandoned due to complicating pneumothorax and difficult access. One patient is awaiting further re-treatment. The overall technical success rate was 90.5%. Multivariate analysis revealed tumor size to be the only significant variable affecting procedural outcome. (p = 0.007, Pearson {chi}{sup 2}) Five patients had complications. There have been no local recurrences. Conclusion. Our experience to date suggests that RFA is a safe and effective, minimally invasive treatment for small renal tumors.

  11. Ducts Sealing Using Injected Spray Sealant, Raleigh, North Carolina (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2014-03-01T23:59:59.000Z

    In multifamily and attached buildings, traditional duct sealing methods are often impractical or costly and disruptive because of the difficulty in accessing leakage sites. In this project, two retrofit duct sealing techniques - manually-applied sealants and injecting a spray sealant, were implemented in several low-rise multi-unit buildings. An analysis on the cost and performance of the two methods are presented. Each method was used in twenty housing units: approximately half of each group of units are single story and the remainder two-story. Results show that duct leakage to the outside was reduced by an average of 59% through the use of manual methods, and by 90% in the units where the injected spray sealant was used. It was found that 73% of the leakage reduction in homes that were treated with injected spray sealant was attributable to the manual sealing done at boots, returns and the air handler. The cost of manually-applying sealant ranged from $275 to $511 per unit and for the injected spray sealant the cost was $700 per unit. Modeling suggests a simple payback of 2.2 years for manual sealing and 4.7 years for the injected spray sealant system. Utility bills were collected for one year before and after the retrofits. Utility bill analysis shows 14% and 16% energy savings using injected spray sealant system and hand sealing procedure respectively in heating season whereas in cooling season, energy savings using injected spray sealant system and hand sealing were both 16%.

  12. Compatibility of Inconel 617 alloy with eutectic fluoride salts at high temperatures

    SciTech Connect (OSTI)

    Luo, A.; Jacobson, D.L. (Department of Chemical, Bio Materials Engineering, Arizona State University, Tempe, Arizona 85287-6006 (United States)); Ponnappan, R. (Universal Energy Systems, Inc., 4401 Dayton-Xenia Road, Dayton, Ohio 45432 (United States))

    1993-01-10T23:59:59.000Z

    Thermal Energy Storage (TES) capsules made of Inconel 617 alloy were filled with high purity eutectic fluoride salts and thermally cycled at eutectic temperature [plus minus]100 K for a period of up to 50,000 hours. The containment life performance characteristics with fluoride salts were examined. The depletion of Al and Cr near the inner edges was found. Atomic Absorption Spectroscopy revealed that both Al and Cr were dissolved in the fluoride salts at high temperatures. The changes in melting temperature and heat of fusion of fluoride salts during thermal cycling were measured with Thermal Differential Analysis. A modified diffusion equation for a one-dimensional semi-infinite bar was applied to the depletion of Al on the interior surfaces of the containers. Good agreement was obtained between the analysis and the measured concentration profiles. The present study suggests that the corrosion was a diffusion controlled process and an expected lifetime of 5--7 years is reasonable and predictable based upon the limited diffusion processes.

  13. Review of U.S. ESCO industry market trends: An empirical analysis of project data

    SciTech Connect (OSTI)

    Goldman, Charles A.; Hopper, Nicole C.; Osborn, Julie G.; Singer, Terry E.

    2003-03-01T23:59:59.000Z

    This article summarizes a comprehensive empirical analysis of U.S. Energy Service Company (ESCO) industry trends and performance. We employ two parallel analytical approaches: a comprehensive survey of firms to estimate total industry size and a database of {approx}1500 ESCO projects, from which we report target markets and typical project characteristics, energy savings and customer economics. We estimate that industry investment for energy-efficiency related services reached US $2 billion in 2000 following a decade of strong growth. ESCO activity is concentrated in states with high economic activity and strong policy support. Typical projects save 150-200 MJ/m2/year and are cost-effective with median benefit/cost ratios of 1.6 and 2.1 for institutional and private sector projects. The median simple payback time is 7 years among institutional customers; 3 years is typical in the private sector. Reliance on DSM incentives has decreased since 1995. Preliminary evidence suggests that state enabling policies have boosted the industry in medium-sized states. ESCOs have proven resilient in the face of restructuring and will probably shift toward selling ''energy solutions,'' with energy efficiency part of a package. We conclude that a private sector energy-efficiency services industry that targets large commercial and industrial customers is viable and self-sustaining with appropriate policy support both financial and non-financial.

  14. Phenolic acids as bioindicators of fly ash deposit revegetation

    SciTech Connect (OSTI)

    L. Djurdjevic; M. Mitrovic; P. Pavlovic; G. Gajic; O. Kostic [Institute for Biological Research 'Sinisa Stankovic,' Belgrade (Serbia and Montenegro). Department of Ecology

    2006-05-15T23:59:59.000Z

    The floristic composition, the abundance, and the cover of pioneer plant species of spontaneously formed plant communities and the content of total phenolics and phenolic acids, as humus constituents, of an ash deposit after 7 years of recultivation were studied. The restoration of both the soil and the vegetation on the ash deposits of the 'Nikola Tesla-A' thermoelectric power plant in Obrenovac (Serbia) is an extremely slow process. Unfavorable physical and chemical characteristics, the toxicity of fly ash, and extreme microclimatic conditions prevented the development of compact plant cover. The abundance and cover of plants increased from the central part of the deposit towards its edges. Festuca rubra L., Crepis setosa Hall., Erigeron canadensis L., Cirsium arvense (L.) Scop., Calamagrostis epigeios (L.) Roth., and Tamarix gallica L. were the most abundant species, thus giving the highest cover. Humus generated during the decomposition process of plant remains represents a completely new product absent in the ash as the starting material. The amount of total phenolics and phenolic acids in fly ash increased from the center of the deposit towards its edges in correlation with the increase in plant abundance and cover. The presence of phenolic acids indicates the ongoing process of humus formation in the ash, in which the most abundant pioneer plants of spontaneously formed plant communities play the main role. Phenolic compounds can serve as reliable bioindicators in an assessment of the success of the recultivation process of thermoelectric power plants' ash deposits.

  15. Current stand characteristics of Louisiana Timberland Harvested between 1975 and 1991. Forest Service research paper

    SciTech Connect (OSTI)

    Rosson, J.F.

    1994-01-01T23:59:59.000Z

    A study population, using 1,216 forest survey continuous forest inventory (C.F.I.) plots, was constructed to analyze the current stocking trends and performance of timberland harvested in Louisiana between 1975 and 1991. A total of 6,888,000 acres was harvested; 4,011,600 acres by partial harvest, 219,900 acres by seed tree and shelterwood methods, 2,562,000 acres by clearcut, and 94,500 acres by salvage cut. Of the 2,454,700 acres of clearcut upland forest types, 640,500 acres converted to the oak-hickory type. It is taking 6 to 7 years, after harvesting, for softwoods to reach the 3.0-inch diameter threshold. Additionally, softwood stand volume 13 to 17 years after clearcut harvest is below that expected for normal sites. Low softwood stocking levels and lengthy regeneration lag time are cited as two possible reasons for low yields at this stage of stand development.

  16. Observational constraints on gauge field production in axion inflation

    SciTech Connect (OSTI)

    Meerburg, P.D. [Department of Astrophysical Sciences, Princeton University, Princeton, NJ 08540 (United States); Pajer, E., E-mail: meerburg@princeton.edu, E-mail: enrico.pajer@gmail.com [Department of Physics, Princeton University, Princeton, NJ 08544 (United States)

    2013-02-01T23:59:59.000Z

    Models of axion inflation are particularly interesting since they provide a natural justification for the flatness of the potential over a super-Planckian distance, namely the approximate shift-symmetry of the inflaton. In addition, most of the observational consequences are directly related to this symmetry and hence are correlated. Large tensor modes can be accompanied by the observable effects of a the shift-symmetric coupling ?F F-tilde to a gauge field. During inflation this coupling leads to a copious production of gauge quanta and consequently a very distinct modification of the primordial curvature perturbations. In this work we compare these predictions with observations. We find that the leading constraint on the model comes from the CMB power spectrum when considering both WMAP 7-year and ACT data. The bispectrum generated by the non-Gaussian inverse-decay of the gauge field leads to a comparable but slightly weaker constraint. There is also a constraint from ?-distortion using TRIS plus COBE/FIRAS data, but it is much weaker. Finally we comment on a generalization of the model to massive gauge fields. When the mass is generated by some light Higgs field, observably large local non-Gaussianity can be produced.

  17. Retention of Halogens in Waste Glass

    SciTech Connect (OSTI)

    Hrma, Pavel R.

    2010-05-01T23:59:59.000Z

    In spite of their potential roles as melting rate accelerators and foam breakers, halogens are generally viewed as troublesome components for glass processing. Of five halogens, F, Cl, Br, I, and At, all but At may occur in nuclear waste. A nuclear waste feed may contain up to 10 g of F, 4 g of Cl, and ?100 mg of Br and I per kg of glass. The main concern is halogen volatility, producing hazardous fumes and particulates, and the radioactive iodine 129 isotope of 1.7x10^7-year half life. Because F and Cl are soluble in oxide glasses and tend to precipitate on cooling, they can be retained in the waste glass in the form of dissolved constituents or as dispersed crystalline inclusions. This report compiles known halogen-retention data in both high-level waste (HLW) and low-activity waste (LAW) glasses. Because of its radioactivity, the main focus is on I. Available data on F and Cl were compiled for comparison. Though Br is present in nuclear wastes, it is usually ignored; no data on Br retention were found.

  18. Accelerator waste - A new challenge for radio-analytics

    SciTech Connect (OSTI)

    Schumann, Dorothea; Neuhausen, Joer; Wohlmuther, Michaelg [Paul Scherrer Institute 5232, Villigen PSI (Switzerland)

    2007-07-01T23:59:59.000Z

    The Paul Scherrer Institute (PSI) at Villigen (Switzerland) operates the most powerful accelerator facility in Europe. Due to the increasing quantities of accelerator waste with almost unknown radionuclide inventory, the development of new radio-analytical methods is an urgent task. Besides the characterization by {gamma}-measurements and dose rate determinations, also the investigation of long-lived radionuclides, being probably essential for a final disposal, is required from Swiss authorities. Chemical separation is necessary for the determination of the majority of these isotopes. As a representative example for such studies, the analytics of a beam dump assembly is introduced. Samples were taken from the target E beam dump station from the 590 MeV proton accelerator facility. The content of several radionuclides with half-lives between 2 and 10{sup 7} years was determined by {gamma}-spectrometry and, after chemical separation, by Liquid Scintillation Counting (LSC) as well as Accelerator Mass Spectrometry (AMS). The results are compared with theoretical predictions. Long-term object of these studies is the elaboration of nuclide vectors, which allow the estimation of nuclide inventories by simple calculations. (authors)

  19. Microwave Power Beaming Infrastructure for Manned Lightcraft Operations: Part 2

    SciTech Connect (OSTI)

    Myrabo, Leik N. [Lightcraft Technologies, Inc., Bennington, VT (United States)

    2008-04-28T23:59:59.000Z

    In the past {approx}7 years, microwave gyrotron technology has rapidly evolved to a critical threshold wherein ultra-energetic space launch missions based on beamed energy propulsion (BEP) now appear eminently feasible. Over the next 20 years, hundred megawatt-class microwave power-beaming stations could be prototyped on high deserts and 3- to 4 km mountain peaks before migrating into low Earth orbit, along with their passive microwave relay satellites. Described herein is a 20 GW rechargeable nuclear power satellite and microwave power-beaming infrastructure designed for manned space launch operations in the year 2025. The technological readiness of 2500 GJ superconducting magnetic energy storage 'batteries', 433-m ultralight space structures, 100 MW liquid droplet radiators, 1-6+ MW gyrotron sources, and mega-scale arrays (e.g., 3000 phase-locked units) is addressed. Microwave BEP is 'breakthrough' technology with the very real potential to radically reduce space access costs by factors of 100 to 1000 in the forseeable future.

  20. Soil organic matter factions of no-tilled and tilled soils and their reactivity with herbicides

    SciTech Connect (OSTI)

    Stearman, G.K.

    1987-01-01T23:59:59.000Z

    Properties of soil humic fractions were determined on surface and 7.5-15.0 cm soil samples of continuously (7-year) no-tilled and tilled cotton, corn, and soybean plots in West Tennessee. Soil humic and fulvic acid were extracted by standard methods and the humic acid was characterized by /sup 13/C-NMR spectroscopy, titration of total acidity and carboxyl groups, and infrared and elemental analysis. Humic acid composition differed by depth and crop. Small differences were observed between tillage systems. Humic acid aliphatic and aromatic carbons ranged from 48 to 65% and 25 to 40% of total peak area, respectively. The humic acids extracted from soils with larger amounts of carbon had larger aliphatic to aromatic ratios, indicating less decomposed organic matter. Carboxyl groups of the humic acids ranged from 9 to 13% and samples from tilled soil had slightly greater amounts of carboxyl and aromatic groups. Carboxyl group determinations by /sup 13/C-NMR, compared more closely with total acidity determinations by titration than with carboxyl determinations by titration. All infrared spectra were similar. Elemental composition of humic acid averaged C, 52.7%, 5.6%; N, 4.8%, and 36.9%.

  1. THE MARS HOPPER: AN IMPULSE DRIVEN, LONG RANGE, LONG-LIVED MOBILE PLATFORM UTILIZING IN-SITU MARTIAN RESOURCES

    SciTech Connect (OSTI)

    Robert C. O'Brien; Mark McKay; Brian Gross; JOnathan Webb

    2001-09-01T23:59:59.000Z

    The requirements for performance by planetary exploration missions are increasing. Landing at a single location to take data is no longer sufficient. Due to the increasing cost, the missions that provide mobile platforms that can acquire data at displaced locations are becoming more attractive. Landers have also had limited range due to power limitations, limited lifetime of subsystems and the inability to negotiate rough terrain. The Center for Space Nuclear Research has designed an instrumented platform that can acquire detailed data at hundreds of locations during its lifetime - a Mars Hopper. The Mars Hopper concept utilizes energy from radioisotopic decay in a manner different from any existing radioisotopic power sources—as a thermal capacitor. By accumulating the heat from radioisotopic decay for long periods, the power of the source can be dramatically increased for short periods. Thus, a radioisotopic thermal rocket (RTR) is possible. The platform will be able to “hop” from one location to the next every 5-7 days with a separation of 5-10 km per hop. Each platform will weigh around 50 kgs unfueled which is the condition at deployment. Consequently, several platforms may be deployed on a single launch from Earth. With a lifetime estimated at 5-7 years, the entire surface of Mars can be mapped in detail by a couple dozen platforms. In addition, Hoppers can collect samples and deliver them to the Mars Science Laboratory for more detailed analysis. The design and performance of the Mars Hopper will be discussed.

  2. Sun-Like Magnetic Cycles in the Rapidly-Rotating Young Solar Analog HD 30495

    E-Print Network [OSTI]

    Egeland, Ricky; Hall, Jeffrey C; Henry, Gregory W

    2015-01-01T23:59:59.000Z

    A growing body of evidence suggests that multiple dynamo mechanisms can drive magnetic variability on different timescales, not only in the Sun but also in other stars. Many solar activity proxies exhibit a quasi-biennial ($\\sim$2 year) variation, which is superimposed upon the dominant 11 year cycle. A well-characterized stellar sample suggests at least two different relationships between rotation period and cycle period, with some stars exhibiting long and short cycles simultaneously. Within this sample, the solar cycle periods are typical of a more rapidly rotating star, implying that the Sun might be in a transitional state or that it has an unusual evolutionary history. In this work, we present new and archival observations of dual magnetic cycles in the young solar analog HD 30495, an $\\sim$1 Gyr-old G1.5V star with a rotation period near 11 days. This star falls squarely on the relationships established by the broader stellar sample, with short-period variations at $\\sim$1.7 years and a long cycle of $...

  3. Climate Research Roadmap Workshop: Summary Report, May 13-14, 2010

    SciTech Connect (OSTI)

    None

    2010-09-01T23:59:59.000Z

    In recognition of the ongoing advances and challenges of climate change research, DOE's Office of Biological and Environmental Research (BER) organized a workshop asking the scientific community to identify the current state of climate science. The goal of the workshop was to determine the research challenges important for developing a predictive understanding of global climate. Participants were asked to focus on interdisciplinary research that capitalized on BER's scientific strengths in Atmospheric System Research, Terrestrial Ecosystem Science, and Climate and Earth System Modeling. Approximately 50 scientists representing these three areas were asked to identify desired outcomes for the next 10 years. Goals were identified for the near (1--3 years), mid (4--7 years), and long term (8--10 years). Discussions were focused by discipline (atmospheric, terrestrial, and modeling) and by latitude (high, temperate, and tropical). In addition, opportunities and needs for integration across disciplines and latitudes were identified with a specific focus on crosscutting challenges and outcomes. BER will use this workshop output to update its strategic plan for climate research.

  4. Built-Environment Wind Turbine Roadmap

    SciTech Connect (OSTI)

    Smith, J.; Forsyth, T.; Sinclair, K.; Oteri, F.

    2012-11-01T23:59:59.000Z

    Although only a small contributor to total electricity production needs, built-environment wind turbines (BWTs) nonetheless have the potential to influence the public's consideration of renewable energy, and wind energy in particular. Higher population concentrations in urban environments offer greater opportunities for project visibility and an opportunity to acquaint large numbers of people to the advantages of wind projects on a larger scale. However, turbine failures will be equally visible and could have a negative effect on public perception of wind technology. This roadmap provides a framework for achieving the vision set forth by the attendees of the Built-Environment Wind Turbine Workshop on August 11 - 12, 2010, at the U.S. Department of Energy's National Renewable Energy Laboratory. The BWT roadmap outlines the stakeholder actions that could be taken to overcome the barriers identified. The actions are categorized as near-term (0 - 3 years), medium-term (4 - 7 years), and both near- and medium-term (requiring immediate to medium-term effort). To accomplish these actions, a strategic approach was developed that identifies two focus areas: understanding the built-environment wind resource and developing testing and design standards. The authors summarize the expertise and resources required in these areas.

  5. PVUSA procurement, acceptance, and rating practices for photovoltaic power plants

    SciTech Connect (OSTI)

    Dows, R.N.; Gough, E.J.

    1995-09-01T23:59:59.000Z

    This report is one in a series of PVUSA reports on PVUSA experiences and lessons learned at the demonstration sites in Davis and Kerman, California, and from participating utility host sites. During the course of approximately 7 years (1988--1994), 10 PV systems have been installed ranging from 20 kW to 500 kW. Six 20-kW emerging module technology arrays, five on universal project-provided structures and one turnkey concentrator, and four turnkey utility-scale systems (200 to 500 kW) were installed. PVUSA took a very proactive approach in the procurement of these systems. In the absence of established procurement documents, the project team developed a comprehensive set of technical and commercial documents. These have been updated with each successive procurement. Working closely with vendors after the award in a two-way exchange provided designs better suited for utility applications. This report discusses the PVUSA procurement process through testing and acceptance, and rating of PV turnkey systems. Special emphasis is placed on the acceptance testing and rating methodology which completes the procurement process by verifying that PV systems meet contract requirements. Lessons learned and recommendations are provided based on PVUSA experience.

  6. Long-term test results from a West Valley actinide-doped reference glass

    SciTech Connect (OSTI)

    Fortner, J.A.; Gerding, T.J.; Bates, J.K.

    1995-07-01T23:59:59.000Z

    Results from drip tests designed to simulate unsaturated conditions in the proposed Yucca Mountain Repository are reported for an actinide-doped glass (reference glass ATM-10) used as a model waste form. These tests have been ongoing for nearly 7 years, with data collected on solution composition (including transuranics), colloid formation and disposition, glass corrosion layers, and solid secondary phases. This test is unique because of its long elapsed time, high content of thorium and transuranics, use of actual groundwater from the proposed site area, use of contact between the glass and sensitized stainless steel in the test, and the variety of analytical procedures applied to the components. Some tests have been terminated, and scanning electron microscopy (SEM) and analytical transmission electron microscopy (AEM) were used to directly measure glass corrosion and identify secondary phases. Other tests remain ongoing, with periodic sampling of the water that had contacted the glass. The importance of integrated testing has been demonstrated, as complex interactions between the glass, the groundwater, and the sensitized stainless steel have been observed. Secondary phases include smectite clay, iron silicates, and brockite. Actinides, except neptunium, concentrate into stable secondary phases. The release of actinides is then controlled by the behavior of these phases.

  7. Underground coal gasification: Development of theory, laboratory experimentation, interpretation, and correlation with the Hanna field tests: Final report

    SciTech Connect (OSTI)

    Gunn, R.D.; Krantz, W.B.

    1987-03-01T23:59:59.000Z

    The following report is a description of a 7 year effort to develop a theoretical understanding of the underground coal gasification process. The approach used is one of the mathematical model development from known chemical and principles, simplification of the models to isolate important effects, and through validation of models to isolate important effects, and through validation of models with laboratory experiments and field test data. Chapter I contains only introductory material. Chapter II describes the development of two models for reverse combustion: a combustion model and a linearized model for combustion front instability. Both models are required for realistic field predictions. Chapter III contains a discussion of a successful forward gasification model. Chapter IV discusses the spalling-enhanced-drying model is applicable to prediction of cavity growth and subsidence. Chapter VI decribes the correct use of energy and material balances for the analysis of UCG field test data. Chapter VII shows how laboratory experiments were used to validate the models for reverse combustion and forward gasification. It is also shown that laboratory combustion tube experiments can be used to simulate gas compositions expected from field tests. Finally, Chapter VII presents results from a comprehensive economic analysis of UCG involving 1296 separate cases. 37 refs., 49 figs., 12 tabs.

  8. Cleaning without chlorinated solvents

    SciTech Connect (OSTI)

    Thompson, L.M.; Simandl, R.F.

    1994-12-31T23:59:59.000Z

    Because of health and environmental concerns, many regulations have been passed in recent years regarding the use of chlorinated solvents. The Oak Ridge Y-12 Plant has had an active program to find alternatives for these solvents used in cleaning applications for the past 7 years. During this time frame, the quantity of solvents purchased has been reduced by 92%. The program has been a twofold effort. Vapor degreasers used in batch cleaning-operations have been replaced by ultrasonic cleaning with aqueous detergent, and other organic solvents have been identified for use in hand-wiping or specialty operations. In order to qualify these alternatives for use, experimentation was conducted on cleaning ability as well as effects on subsequent operations such as welding, painting and bonding. Cleaning ability was determined using techniques such as X-ray photoelectron spectroscopy (XPS) and Fourier Transform Infrared Spectroscopy (FTIR) which are capable of examining monolayer levels of contamination on a surface. Solvents have been identified for removal of rust preventative oils, lapping oils, machining coolants, lubricants, greases, and mold releases. Solvents have also been evaluated for cleaning urethane foam spray guns, swelling of urethanes and swelling of epoxies.

  9. Aerosol remote sensing in polar regions

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Tomasi, C.; Wagener, R.; Kokhanovsky, A. A.; Lupi, A.; Ritter, C.; Smirnov, A.; O Neill, N. T.; Stone, R. S.; Holben, B. N.; Nyeki, S.; Wehrli, C.; Stohl, A.; Mazzola, M.; Lanconelli, C.; Vitale, V.; Stebel, K.; Aaltonen, V.; de Leeuw, G.; Rodriguez, E.; Herber, A. B.; Radionov, V. F.; Zielinski, T.; Petelski, T.; Sakerin, S. M.; Kabanov, D. M.; Xue, Y.; Mei, L.; Istomina, L.; Wagener, R.; McArthur, B.; Sobolewski, P. S.; Kivi, R.; Courcoux, Y.; Larouche, P.; Broccardo, S.; Piketh, S. J.

    2015-01-01T23:59:59.000Z

    Multi-year sets of ground-based sun-photometer measurements conducted at 12 Arctic sites and 9 Antarctic sites were examined to determine daily mean values of aerosol optical thickness ?(?) at visible and near-infrared wavelengths, from which best-fit values of Ångström's exponent ? were calculated. Analysing these data, the monthly mean values of ?(0.50 ?m) and ? and the relative frequency histograms of the daily mean values of both parameters were determined for winter–spring and summer–autumn in the Arctic and for austral summer in Antarctica. The Arctic and Antarctic covariance plots of the seasonal median values of ? versus ?(0.50 ?m) showed: (i) a considerable increase in ?(0.50 ?m) for the Arctic aerosol from summer to winter–spring, without marked changes in ?; and (ii) a marked increase in ?(0.50 ?m) passing from the Antarctic Plateau to coastal sites, whereas ? decreased considerably due to the larger fraction of sea-salt aerosol. Good agreement was found when comparing ground-based sun-photometer measurements of ?(?) and ? at Arctic and Antarctic coastal sites with Microtops measurements conducted during numerous AERONET/MAN cruises from 2006 to 2013 in three Arctic Ocean sectors and in coastal and off-shore regions of the Southern Atlantic, Pacific, and Indian Oceans, and the Antarctic Peninsula. Lidar measurements were also examined to characterise vertical profiles of the aerosol backscattering coefficient measured throughout the year at Ny-Ålesund. Satellite-based MODIS, MISR, and AATSR retrievals of ?(?) over large parts of the oceanic polar regions during spring and summer were in close agreement with ship-borne and coastal ground-based sun-photometer measurements. An overview of the chemical composition of mode particles is also presented, based on in-situ measurements at Arctic and Antarctic sites. Fourteen log-normal aerosol number size-distributions were defined to represent the average features of nuclei, accumulation and coarse mode particles for Arctic haze, summer background aerosol, Asian dust and boreal forest fire smoke, and for various background austral summer aerosol types at coastal and high-altitude Antarctic sites. The main columnar aerosol optical characteristics were determined for all 14 particle modes, based on in-situ measurements of the scattering and absorption coefficients. Diurnally averaged direct aerosol-induced radiative forcing and efficiency were calculated for a set of multimodal aerosol extinction models, using various Bidirectional Reflectance Distribution Function models over vegetation-covered, oceanic and snow-covered surfaces. These gave a reliable measure of the pronounced effects of aerosols on the radiation balance of the surface–atmosphere system over polar regions.

  10. Assessing the feasibility of volumetric-modulated arc therapy using simultaneous integrated boost (SIB-VMAT): An analysis for complex head-neck, high-risk prostate and rectal cancer cases

    SciTech Connect (OSTI)

    Cilla, Savino, E-mail: savinocilla@gmail.com [Medical Physics Unit, Fondazione di ricerca e cura “Giovanni Paolo II,” Università Cattolica del Sacro Cuore, Campobasso (Italy); Deodato, Francesco; Digesù, Cinzia; Macchia, Gabriella; Picardi, Vincenzo; Ferro, Marica [Radiation Oncology Unit, Fondazione di ricerca e cura “Giovanni Paolo II,” Università Cattolica del Sacro Cuore, Campobasso (Italy); Sallustio, Giuseppina [Radiology Unit, Fondazione di ricerca e cura “Giovanni Paolo II,” Università Cattolica del Sacro Cuore, Campobasso (Italy); De Spirito, Marco; Piermattei, Angelo [Physics Institute, Università Cattolica del Sacro Cuore, Rome (Italy); Morganti, Alessio G. [Radiation Oncology Unit, Fondazione di ricerca e cura “Giovanni Paolo II,” Università Cattolica del Sacro Cuore, Campobasso (Italy)

    2014-04-01T23:59:59.000Z

    Intensity-modulated radiotherapy (IMRT) allowed the simultaneous delivery of different doses to different target volumes within a single fraction, an approach called simultaneous integrated boost (SIB). As consequence, the fraction dose to the boost volume can be increased while keeping low doses to the elective volumes, and the number of fractions and overall treatment time will be reduced, translating into better radiobiological effectiveness. In recent years, volumetric-modulated arc therapy (VMAT) has been shown to provide similar plan quality with respect to fixed-field IMRT but with large reduction in treatment time and monitor units (MUs) number. However, the feasibility of VMAT when used with SIB strategy has few investigations to date. We explored the potential of VMAT in a SIB strategy for complex cancer sites. A total of 15 patients were selected, including 5 head-and-neck, 5 high-risk prostate, and 5 rectal cancer cases. Both a double-arc VMAT and a 7-field IMRT plan were generated for each case using Oncentra MasterPlan treatment planning system for an Elekta Precise linac. Dosimetric indexes for targets and organs at risk (OARs) were compared based on dose-volume histograms. Conformity index, homogeneity index, and dose-contrast index were used for target analyses. The equivalent uniform doses and the normal tissue complication probabilities were calculated for main OARs. MUs number and treatment time were analyzed to score treatment efficiency. Pretreatment dosimetry was performed using 2-dimensional (2D)-array dosimeter. SIB-VMAT plans showed a high level of fluence modulation needed for SIB treatments, high conformal dose distribution, similar target coverage, and a tendency to improve OARs sparing compared with the benchmark SIB-IMRT plans. The median treatment times reduced from 13 to 20 minutes to approximately 5 minutes for all cases with SIB-VMAT, with a MUs reduction up to 22.5%. The 2D-array ion-chambers' measurements reported an agreement of more than 95% for a criterion of 3% to 3 mm. SIB-VMAT was able to combine the advantages of conventional SIB-IMRT with its highly conformal dose distribution and OARs sparing and the advantages of 3D-conformal radiotherapy with its fast delivery.

  11. HDRMC, an accelerated Monte Carlo dose calculator for high dose rate brachytherapy with CT-compatible applicators

    SciTech Connect (OSTI)

    Chibani, Omar, E-mail: omar.chibani@fccc.edu; C-M Ma, Charlie [Fox Chase Cancer Center, Philadelphia, Pennsylvania 19111 (United States)] [Fox Chase Cancer Center, Philadelphia, Pennsylvania 19111 (United States)

    2014-05-15T23:59:59.000Z

    Purpose: To present a new accelerated Monte Carlo code for CT-based dose calculations in high dose rate (HDR) brachytherapy. The new code (HDRMC) accounts for both tissue and nontissue heterogeneities (applicator and contrast medium). Methods: HDRMC uses a fast ray-tracing technique and detailed physics algorithms to transport photons through a 3D mesh of voxels representing the patient anatomy with applicator and contrast medium included. A precalculated phase space file for the{sup 192}Ir source is used as source term. HDRM is calibrated to calculated absolute dose for real plans. A postprocessing technique is used to include the exact density and composition of nontissue heterogeneities in the 3D phantom. Dwell positions and angular orientations of the source are reconstructed using data from the treatment planning system (TPS). Structure contours are also imported from the TPS to recalculate dose-volume histograms. Results: HDRMC was first benchmarked against the MCNP5 code for a single source in homogenous water and for a loaded gynecologic applicator in water. The accuracy of the voxel-based applicator model used in HDRMC was also verified by comparing 3D dose distributions and dose-volume parameters obtained using 1-mm{sup 3} versus 2-mm{sup 3} phantom resolutions. HDRMC can calculate the 3D dose distribution for a typical HDR cervix case with 2-mm resolution in 5 min on a single CPU. Examples of heterogeneity effects for two clinical cases (cervix and esophagus) were demonstrated using HDRMC. The neglect of tissue heterogeneity for the esophageal case leads to the overestimate of CTV D90, CTV D100, and spinal cord maximum dose by 3.2%, 3.9%, and 3.6%, respectively. Conclusions: A fast Monte Carlo code for CT-based dose calculations which does not require a prebuilt applicator model is developed for those HDR brachytherapy treatments that use CT-compatible applicators. Tissue and nontissue heterogeneities should be taken into account in modern HDR brachytherapy planning.

  12. Postoperative Radiotherapy for Prostate Cancer: A Comparison of Four Consensus Guidelines and Dosimetric Evaluation of 3D-CRT Versus Tomotherapy IMRT

    SciTech Connect (OSTI)

    Malone, Shawn, E-mail: smalone@ottawahospital.on.ca [Division of Radiation Oncology, Ottawa Hospital, University of Ottawa, Ottawa, Ontario (Canada)] [Division of Radiation Oncology, Ottawa Hospital, University of Ottawa, Ottawa, Ontario (Canada); Croke, Jennifer [Division of Radiation Oncology, Ottawa Hospital, University of Ottawa, Ottawa, Ontario (Canada)] [Division of Radiation Oncology, Ottawa Hospital, University of Ottawa, Ottawa, Ontario (Canada); Roustan-Delatour, Nicolas; Belanger, Eric [Department of Pathology, Ottawa Hospital, University of Ottawa, Ottawa, Ontario (Canada)] [Department of Pathology, Ottawa Hospital, University of Ottawa, Ottawa, Ontario (Canada); Avruch, Leonard [Department of Radiology, Ottawa Hospital, University of Ottawa, Ottawa, Ontario (Canada)] [Department of Radiology, Ottawa Hospital, University of Ottawa, Ottawa, Ontario (Canada); Malone, Colin [Division of Radiation Oncology, Ottawa Hospital, University of Ottawa, Ottawa, Ontario (Canada)] [Division of Radiation Oncology, Ottawa Hospital, University of Ottawa, Ottawa, Ontario (Canada); Morash, Christopher [Division of Urology, Ottawa Hospital, University of Ottawa, Ottawa, Ontario (Canada)] [Division of Urology, Ottawa Hospital, University of Ottawa, Ottawa, Ontario (Canada); Kayser, Cathleen; Underhill, Kathryn; Li Yan; Malone, Kyle [Division of Radiation Oncology, Ottawa Hospital, University of Ottawa, Ottawa, Ontario (Canada)] [Division of Radiation Oncology, Ottawa Hospital, University of Ottawa, Ottawa, Ontario (Canada); Nyiri, Balazs [Department of Medical Physics, Ottawa Hospital, University of Ottawa, Ottawa, Ontario (Canada)] [Department of Medical Physics, Ottawa Hospital, University of Ottawa, Ottawa, Ontario (Canada); Spaans, Johanna [Division of Radiation Oncology, Ottawa Hospital, University of Ottawa, Ottawa, Ontario (Canada)] [Division of Radiation Oncology, Ottawa Hospital, University of Ottawa, Ottawa, Ontario (Canada)

    2012-11-01T23:59:59.000Z

    Purpose: Despite the benefits of adjuvant radiotherapy after radical prostatectomy, approximately one-half of patients relapse. Four consensus guidelines have been published (European Organization for Research and Treatment of Cancer, Faculty of Radiation Oncology Genito-Urinary Group, Princess Margaret Hospital, Radiation Therapy Oncology Group) with the aim of standardizing the clinical target volume (CTV) delineation and improve outcomes. To date, no attempt has been made to compare these guidelines in terms of treatment volumes or organ at risk (OAR) irradiation. The extent to which the guideline-derived plans meet the dosimetric constraints of present trials or of the Quantitative Analysis of Normal Tissue Effects in the Clinic (QUANTEC) trial is also unknown. Our study also explored the dosimetric benefits of intensity-modulated radiotherapy (IMRT). Methods and Materials: A total of 20 patients treated with postoperative RT were included. The three-dimensional conformal radiotherapy (3D-CRT) plans were applied to cover the guideline-generated planning target volumes (66 Gy in 33 fractions). Dose-volume histograms (DVHs) were analyzed for CTV/planning target volume coverage and to evaluate OAR irradiation. The OAR DVHs were compared with the constraints proposed in the QUANTEC and Radiotherapy and Androgen Deprivation In Combination After Local Surgery (RADICALS) trials. 3D-CRT plans were compared with the tomotherapy plans for the Radiation Therapy Oncology Group planning target volume to evaluate the advantages of IMRT. Results: The CTV differed significantly between guidelines (p < 0.001). The European Organization for Research and Treatment of Cancer-CTVs were significantly smaller than the other CTVs (p < 0.001). Differences in prostate bed coverage superiorly accounted for the major volumetric differences between the guidelines. Using 3D-CRT, the DVHs rarely met the QUANTEC or RADICALS rectal constraints, independent of the guideline used. The RADICALS bladder constraints were met most often by the European Organization for Research and Treatment of Cancer consensus guideline (14 of 20). The tomotherapy IMRT plans resulted in significant OAR sparing compared with the 3D-CRT plans; however, the RADICALS and QUANTEC criteria were still missed in a large percentage of cases. Conclusion: Treatment volumes using the current consensus guidelines differ significantly. For the four CTV guidelines, the rectal and bladder DVH constraints proposed in the QUANTEC and RADICALS trials are rarely met with 3D-CRT. IMRT results in significant OAR sparing; however, the RADICALS dose constraints are still missed for a large percentage of cases. The rectal and bladder constraints of RADICALS should be modified to avoid a reduction in the CTVs.

  13. Horizontal Velocity and Variance Measurements in the Stable Boundary Layer Using Doppler Lidar: Sensitivity to Averaging Procedures

    SciTech Connect (OSTI)

    Pichugina, Y. L.; Banta, R. M.; Kelley, N. D.; Jonkman, B. J.; Tucker, S. C.; Newsom, R. K.; Brewer, W. A.

    2008-08-01T23:59:59.000Z

    Quantitative data on turbulence variables aloft--above the region of the atmosphere conveniently measured from towers--have been an important but difficult measurement need for advancing understanding and modeling of the stable boundary layer (SBL). Vertical profiles of streamwise velocity variances obtained from NOAA's high-resolution Doppler lidar (HRDL), which have been shown to be approximately equal to turbulence kinetic energy (TKE) for stable conditions, are a measure of the turbulence in the SBL. In the present study, the mean horizontal wind component U and variance {sigma}2u were computed from HRDL measurements of the line-of-sight (LOS) velocity using a method described by Banta et al., which uses an elevation (vertical slice) scanning technique. The method was tested on datasets obtained during the Lamar Low-Level Jet Project (LLLJP) carried out in early September 2003, near the town of Lamar in southeastern Colorado. This paper compares U with mean wind speed obtained from sodar and sonic anemometer measurements. The results for the mean U and mean wind speed measured by sodar and in situ instruments for all nights of LLLJP show high correlation (0.71-0.97), independent of sampling strategies and averaging procedures, and correlation coefficients consistently >0.9 for four high-wind nights, when the low-level jet speeds exceeded 15 m s{sup -1} at some time during the night. Comparison of estimates of variance, on the other hand, proved sensitive to both the spatial and temporal averaging parameters. Several series of averaging tests are described, to find the best correlation between TKE calculated from sonic anemometer data at several tower levels and lidar measurements of horizontal-velocity variance {sigma}{sup 2}{sub u}. Because of the nonstationarity of the SBL data, the best results were obtained when the velocity data were first averaged over intervals of 1 min, and then further averaged over 3-15 consecutive 1-min intervals, with best results for the 10- and 15-min averaging periods. For these cases, correlation coefficients exceeded 0.9. As a part of the analysis, Eulerian integral time scales ({tau}) were estimated for the four high-wind nights. Time series of {tau} through each night indicated erratic behavior consistent with the nonstationarity. Histograms of {tau} showed a mode at 4-5 s, but frequent occurrences of larger {tau} values, mostly between 10 and 100 s.

  14. Aerosol remote sensing in polar regions

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Tomasi, C.; Wagener, R.; Kokhanovsky, A. A.; Lupi, A.; Ritter, C.; Smirnov, A.; O Neill, N. T.; Stone, R. S.; Holben, B. N.; Nyeki, S.; et al

    2015-01-01T23:59:59.000Z

    Multi-year sets of ground-based sun-photometer measurements conducted at 12 Arctic sites and 9 Antarctic sites were examined to determine daily mean values of aerosol optical thickness ?(?) at visible and near-infrared wavelengths, from which best-fit values of Ångström's exponent ? were calculated. Analysing these data, the monthly mean values of ?(0.50 ?m) and ? and the relative frequency histograms of the daily mean values of both parameters were determined for winter–spring and summer–autumn in the Arctic and for austral summer in Antarctica. The Arctic and Antarctic covariance plots of the seasonal median values of ? versus ?(0.50 ?m) showed: (i)more »a considerable increase in ?(0.50 ?m) for the Arctic aerosol from summer to winter–spring, without marked changes in ?; and (ii) a marked increase in ?(0.50 ?m) passing from the Antarctic Plateau to coastal sites, whereas ? decreased considerably due to the larger fraction of sea-salt aerosol. Good agreement was found when comparing ground-based sun-photometer measurements of ?(?) and ? at Arctic and Antarctic coastal sites with Microtops measurements conducted during numerous AERONET/MAN cruises from 2006 to 2013 in three Arctic Ocean sectors and in coastal and off-shore regions of the Southern Atlantic, Pacific, and Indian Oceans, and the Antarctic Peninsula. Lidar measurements were also examined to characterise vertical profiles of the aerosol backscattering coefficient measured throughout the year at Ny-Ålesund. Satellite-based MODIS, MISR, and AATSR retrievals of ?(?) over large parts of the oceanic polar regions during spring and summer were in close agreement with ship-borne and coastal ground-based sun-photometer measurements. An overview of the chemical composition of mode particles is also presented, based on in-situ measurements at Arctic and Antarctic sites. Fourteen log-normal aerosol number size-distributions were defined to represent the average features of nuclei, accumulation and coarse mode particles for Arctic haze, summer background aerosol, Asian dust and boreal forest fire smoke, and for various background austral summer aerosol types at coastal and high-altitude Antarctic sites. The main columnar aerosol optical characteristics were determined for all 14 particle modes, based on in-situ measurements of the scattering and absorption coefficients. Diurnally averaged direct aerosol-induced radiative forcing and efficiency were calculated for a set of multimodal aerosol extinction models, using various Bidirectional Reflectance Distribution Function models over vegetation-covered, oceanic and snow-covered surfaces. These gave a reliable measure of the pronounced effects of aerosols on the radiation balance of the surface–atmosphere system over polar regions.« less

  15. SU-E-I-92: Is Photon Starvation Preventing Metal Artifact Reduction Algorithm From Working in KVCT?

    SciTech Connect (OSTI)

    Paudel, M [University of Alberta, Cross Cancer Institute, Edmonton, AB (Canada); currently at University of Toronto, Sunnybrook Health Sciences Center, Toronto, ON (Canada); MacKenzie, M; Fallone, B; Rathee, S [University of Alberta, Cross Cancer Institute, Edmonton, AB (Canada)

    2014-06-01T23:59:59.000Z

    Purpose: High density/high atomic number metallic objects create shading and streaking metal artifacts in the CT image that can cause inaccurate delineation of anatomical structures or inaccurate radiation dose calculation. A modified iterative maximum-likelihood polychromatic algorithm for CT (mIMPACT) that models the energy response of detectors, photon interaction processes and beam polychromaticity has successfully reduced metal artifacts in MVCT. Our extension of mIMPACT in kVCT did not significantly reduce metal artifacts for high density metal like steel. We hypothesize that photon starvation may result in the measured data in a commercial kVCT imaging beam. Methods: We measured attenuation of a range of steel plate thicknesses, sandwiched between two 12cm thick solid water blocks, using a Phillips Big Bore CTTM scanner in scout acquisition mode with 120kVp and 200mAs. The transmitted signal (y) was normalized to the air scan signal (y{sub 0}) to get attenuation [i.e., ln(y/y{sub 0})] data for a detector. Results: Below steel plate thickness of 13.4mm, the variations in measured attenuation as a function of view number are characterized by a quantum noise and show increased attenuation with metal thickness. On or above this thickness the attenuation shows discrete levels in addition to the quantum noise. Some views have saturated attenuation value. The histograms of the measured attenuation for up to 36.7mm of steel show this trend. The detector signal is so small that the quantization levels in the analog to digital (A-to-D) converter are visible, a clear indication of photon starvation. Conclusion: Photons reaching the kVCT detector after passing through a thick metal plate are either so low in number that the signal measured has large quantum noise, or are completely absorbed inside the plate creating photon starvation. This is un-interpretable by the mIMPACT algorithm and cannot reduce metal artifacts in kVCT for certain realistic thicknesses of steel hip implants. Moti Raj Paudel is supported by the Vanier Canada Graduate Scholarship, the Endowed Graduate Scholarship in Oncology and the Dissertation Fellowship at the University of Alberta. The authors acknowledge the CIHR operating grant number MOP 53254.

  16. Radiation-Induced Rib Fractures After Hypofractionated Stereotactic Body Radiation Therapy: Risk Factors and Dose-Volume Relationship

    SciTech Connect (OSTI)

    Asai, Kaori [Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, Fukuoka (Japan)] [Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, Fukuoka (Japan); Shioyama, Yoshiyuki, E-mail: shioyama@radiol.med.kyushu-u.ac.jp [Department of Heavy Particle Therapy and Radiation Oncology, Graduate School of Medical Sciences, Kyushu University, Fukuoka (Japan)] [Department of Heavy Particle Therapy and Radiation Oncology, Graduate School of Medical Sciences, Kyushu University, Fukuoka (Japan); Nakamura, Katsumasa; Sasaki, Tomonari; Ohga, Saiji; Nonoshita, Takeshi [Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, Fukuoka (Japan)] [Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, Fukuoka (Japan); Yoshitake, Tadamasa [Department of Heavy Particle Therapy and Radiation Oncology, Graduate School of Medical Sciences, Kyushu University, Fukuoka (Japan)] [Department of Heavy Particle Therapy and Radiation Oncology, Graduate School of Medical Sciences, Kyushu University, Fukuoka (Japan); Ohnishi, Kayoko [Department of Radiology, National Center for Global Health and Medicine, Tokyo (Japan)] [Department of Radiology, National Center for Global Health and Medicine, Tokyo (Japan); Terashima, Kotaro; Matsumoto, Keiji [Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, Fukuoka (Japan)] [Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, Fukuoka (Japan); Hirata, Hideki [Department of Health Sciences, Graduate School of Medical Sciences, Kyushu University, Fukuoka (Japan)] [Department of Health Sciences, Graduate School of Medical Sciences, Kyushu University, Fukuoka (Japan); Honda, Hiroshi [Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, Fukuoka (Japan)] [Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, Fukuoka (Japan)

    2012-11-01T23:59:59.000Z

    Purpose: The purpose of this study was to clarify the incidence, the clinical risk factors, and the dose-volume relationship of radiation-induced rib fracture (RIRF) after hypofractionated stereotactic body radiation therapy (SBRT). Methods and Materials: One hundred sixteen patients treated with SBRT for primary or metastatic lung cancer at our institution, with at least 6 months of follow-up and no previous overlapping radiation exposure, were included in this study. To determine the clinical risk factors associated with RIRF, correlations between the incidence of RIRF and the variables, including age, sex, diagnosis, gross tumor volume diameter, rib-tumor distance, and use of steroid administration, were analyzed. Dose-volume histogram analysis was also conducted. Regarding the maximum dose, V10, V20, V30, and V40 of the rib, and the incidences of RIRF were compared between the two groups divided by the cutoff value determined by the receiver operating characteristic curves. Results: One hundred sixteen patients and 374 ribs met the inclusion criteria. Among the 116 patients, 28 patients (46 ribs) experienced RIRF. The estimated incidence of rib fracture was 37.7% at 3 years. Limited distance from the rib to the tumor (<2.0 cm) was the only significant risk factor for RIRF (p = 0.0001). Among the dosimetric parameters used for receiver operating characteristic analysis, the maximum dose showed the highest area under the curve. The 3-year estimated risk of RIRF and the determined cutoff value were 45.8% vs. 1.4% (maximum dose, {>=}42.4 Gy or less), 51.6% vs. 2.0% (V40, {>=}0.29 cm{sup 3} or less), 45.8% vs. 2.2% (V30, {>=}1.35 cm{sup 3} or less), 42.0% vs. 8.5% (V20, {>=}3.62 cm{sup 3} or less), or 25.9% vs. 10.5% (V10, {>=}5.03 cm{sup 3} or less). Conclusions: The incidence of RIRF after hypofractionated SBRT is relatively high. The maximum dose and high-dose volume are strongly correlated with RIRF.

  17. Beam geometry selection using sequential beam addition

    SciTech Connect (OSTI)

    Popple, Richard A., E-mail: rpopple@uabmc.edu; Brezovich, Ivan A.; Fiveash, John B. [Department of Radiation Oncology, The University of Alabama at Birmingham, 1720 2nd Avenue South, Birmingham, Alabama 35294 (United States)] [Department of Radiation Oncology, The University of Alabama at Birmingham, 1720 2nd Avenue South, Birmingham, Alabama 35294 (United States)

    2014-05-15T23:59:59.000Z

    Purpose: The selection of optimal beam geometry has been of interest since the inception of conformal radiotherapy. The authors report on sequential beam addition, a simple beam geometry selection method, for intensity modulated radiation therapy. Methods: The sequential beam addition algorithm (SBA) requires definition of an objective function (score) and a set of candidate beam geometries (pool). In the first iteration, the optimal score is determined for each beam in the pool and the beam with the best score selected. In the next iteration, the optimal score is calculated for each beam remaining in the pool combined with the beam selected in the first iteration, and the best scoring beam is selected. The process is repeated until the desired number of beams is reached. The authors selected three treatment sites, breast, lung, and brain, and determined beam arrangements for up to 11 beams from a pool comprised of 25 equiangular transverse beams. For the brain, arrangements were additionally selected from a pool of 22 noncoplanar beams. Scores were determined for geometries comprised equiangular transverse beams (EQA), as well as two tangential beams for the breast case. Results: In all cases, SBA resulted in scores superior to EQA. The breast case had the strongest dependence on beam geometry, for which only the 7-beam EQA geometry had a score better than the two tangential beams, whereas all SBA geometries with more than two beams were superior. In the lung case, EQA and SBA scores monotonically improved with increasing number of beams; however, SBA required fewer beams to achieve scores equivalent to EQA. For the brain case, SBA with a coplanar pool was equivalent to EQA, while the noncoplanar pool resulted in slightly better scores; however, the dose-volume histograms demonstrated that the differences were not clinically significant. Conclusions: For situations in which beam geometry has a significant effect on the objective function, SBA can identify arrangements equivalent to equiangular geometries but using fewer beams. Furthermore, SBA provides the value of the objective function as the number of beams is increased, allowing the planner to select the minimal beam number that achieves the clinical goals. The method is simple to implement and could readily be incorporated into an existing optimization system.

  18. Dosimetric feasibility of real-time MRI-guided proton therapy

    SciTech Connect (OSTI)

    Moteabbed, M., E-mail: mmoteabbed@partners.org; Schuemann, J.; Paganetti, H. [Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts 02114 (United States)

    2014-11-01T23:59:59.000Z

    Purpose: Magnetic resonance imaging (MRI) is a prime candidate for image-guided radiotherapy. This study was designed to assess the feasibility of real-time MRI-guided proton therapy by quantifying the dosimetric effects induced by the magnetic field in patients’ plans and identifying the associated clinical consequences. Methods: Monte Carlo dose calculation was performed for nine patients of various treatment sites (lung, liver, prostate, brain, skull-base, and spine) and tissue homogeneities, in the presence of 0.5 and 1.5 T magnetic fields. Dose volume histogram (DVH) parameters such as D{sub 95}, D{sub 5}, and V{sub 20} as well as equivalent uniform dose were compared for the target and organs at risk, before and after applying the magnetic field. The authors further assessed whether the plans affected by clinically relevant dose distortions could be corrected independent of the planning system. Results: By comparing the resulting dose distributions and analyzing the respective DVHs, it was determined that despite the observed lateral beam deflection, for magnetic fields of up to 0.5 T, neither was the target coverage jeopardized nor was the dose to the nearby organs increased in all cases except for prostate. However, for a 1.5 T magnetic field, the dose distortions were more pronounced and of clinical concern in all cases except for spine. In such circumstances, the target was severely underdosed, as indicated by a decrease in D{sub 95} of up to 41% of the prescribed dose compared to the nominal situation (no magnetic field). Sites such as liver and spine were less affected due to higher tissue homogeneity, typically smaller beam range, and the choice of beam directions. Simulations revealed that small modifications to certain plan parameters such as beam isocenter (up to 19 mm) and gantry angle (up to 10°) are sufficient to compensate for the magnetic field-induced dose disturbances. The authors’ observations indicate that the degree of required corrections strongly depends on the beam range and direction relative to the magnetic field. This method was also applicable to more heterogeneous scenarios such as skull-base tumors. Conclusions: This study confirmed the dosimetric feasibility of real-time MRI-guided proton therapy and delivering a clinically acceptable dose to patients with various tumor locations within magnetic fields of up to 1.5 T. This work could serve as a guide and encouragement for further efforts toward clinical implementation of hybrid MRI–proton gantry systems.

  19. Applicability of Operational Research Techniques in CANDU Nuclear Plant Maintenance

    SciTech Connect (OSTI)

    Doyle, E. Kevin [Bruce Power LP, Box 4000B12, Tiverton, Ont., N0G2T0 (Canada)

    2002-07-01T23:59:59.000Z

    As previously reported at ICONE 6 in New Orleans, 1996, and ICONE 9 in Niece, 2001, the use of various maintenance optimization techniques at Bruce has lead to cost effective preventive maintenance applications for complex systems. Innovative practices included greatly reducing Reliability Centered Maintenance (RCM) costs while maintaining the accuracy of the analysis. The optimization strategy has undergone further evolution and at the present an Integrated Maintenance Program (IMP) is being put in place. Further cost refinement of the station preventive maintenance strategy whereby decisions are based on statistical analysis of historical failure data is being evaluated. A wide range of Operational Research (OR) literature was reviewed for implementation issues and several encouraging areas were found that will assist in the current effort of evaluating maintenance optimization techniques for nuclear power production. The road ahead is expected to consist first of resolving 25 years of data issues and preserving the data via appropriate knowledge system techniques while post war demographics permit experts to input into the system. Subsequent analytical techniques will emphasize total simplicity to obtain the requisite buy in from Corporate Executives who possibly are not trained in Operational Research. Case studies of containment airlock seal failures are used to illustrate the direct applicability of stochastic processes. Airlocks and transfer chambers were chosen as they have long been known as high maintenance items. Also, the very significant financial consequences of this type of failure will help to focus the attention of Senior Management on the effort. Despite substantial investment in research, improvement in the design of the seal material or configuration has not been achieved beyond the designs completed in the 1980's. Overall, the study showed excellent agreement of the relatively quick stochastic methods with the maintenance programs produced at great cost over years of trial and error. The pivotal role of expert opinion via experienced users/problem owners/maintenance engineers in all phases of the method and its application was noted and will be explored in subsequent efforts. The results are displayed via economic alternatives to more easily attract the attention of Maintenance Managers. Graphical overviews of the data demonstrated that substantial insight can be gained by simply organizing the data into statistically meaningful arrays such as histograms. The conclusions highlight several very positive avenues to evaluate at this particular juncture in time. (author)

  20. Tropical and subtropical cloud transitions in weather and climate prediction models: the GCSS/WGNE Pacific Cross-Section Intercomparison (GPCI)

    SciTech Connect (OSTI)

    Teixeira, J.; Cardoso, S.; Bonazzola, M.; Cole, Jason N.; DelGenio, Anthony D.; DeMott, C.; Franklin, A.; Hannay, Cecile; Jakob, Christian; Jiao, Y.; Karlsson, J.; Kitagawa, H.; Koehler, M.; Kuwano-Yoshida, A.; LeDrian, C.; Lock, Adrian; Miller, M.; Marquet, P.; Martins, J.; Mechoso, C. R.; Meijgaard, E. V.; Meinke, I.; Miranda, P.; Mironov, D.; Neggers, Roel; Pan, H. L.; Randall, David A.; Rasch, Philip J.; Rockel, B.; Rossow, William B.; Ritter, B.; Siebesma, A. P.; Soares, P.; Turk, F. J.; Vaillancourt, P.; Von Engeln, A.; Zhao, M.

    2011-11-01T23:59:59.000Z

    A model evaluation approach is proposed where weather and climate prediction models are analyzed along a Pacific Ocean cross-section, from the stratocumulus regions off the coast of California, across the shallow convection dominated trade-winds, to the deep convection regions of the ITCZ: the GCSS/WGNE Pacific Cross-section Intercomparison (GPCI). The main goal of GPCI is to evaluate, and help understand and improve the representation of tropical and sub-tropical cloud processes in weather and climate prediction models. In this paper, a detailed analysis of cloud regime transitions along the cross-section from the sub-tropics to the tropics for the season JJA of 1998 is presented. This GPCI study confirms many of the typical weather and climate prediction model problems in the representation of clouds: underestimation of clouds in the stratocumulus regime by most models with the corresponding consequences in terms of shortwave radiation biases; overestimation of clouds by the ECMWF Re-Analysis (ERA40) in the deep tropics (in particular) with the corresponding impact in the outgoing longwave radiation; large spread between the different models in terms of cloud cover, liquid water path and shortwave radiation; significant differences between the models in terms of vertical crosssections of cloud properties (in particular), vertical velocity and relative humidity. An alternative analysis of cloud cover mean statistics is proposed where sharp gradients in cloud cover along the GPCI transect are taken into account. This analysis shows that the negative cloud bias of some models and ERA40 in the stratocumulus regions (as compared to ISCCP) is associated not only with lower values of cloud cover in these regimes, but also with a stratocumulus-to-cumulus transition that occurs too early along the trade-wind Lagrangian trajectory. Histograms of cloud cover along the cross-section differ significantly between models. Some models exhibit a quasi-bimodal structure with cloud cover being either very large (close to 100%) or very small, while other models show a more continuous transition. The ISCCP observations suggest that reality is in-between these two extreme examples. These different patterns reflect the diverse nature of the cloud, boundary layer, and convection parameterizations in the participating weather and climate prediction models.

  1. A Method for the Selection of Exploration Areas for Unconformity Uranium Deposits

    SciTech Connect (OSTI)

    Harris, DeVerle P. [University of Arizona, Geoscience Department (United States)], E-mail: deverle@burningvan.net; Zaluski, Gerard [Cameco Corporation, Exploration Office (Canada); Marlatt, James [Uravan Minerals, Inc. (Canada)

    2009-06-15T23:59:59.000Z

    The method we propose employs two analyses: (1) exploration simulation and risk valuation and (2) portfolio optimization. The first analysis, implemented by the investment worth system (IWS), uses Monte Carlo simulation to integrate a wide spectrum of uncertain and varied components to a relative frequency histogram for net present value of the exploration investment, which is converted to a risk-adjusted value (RAV). Iterative rerunning of the IWS enables the mapping of the relationship of RAV to magnitude of exploration expenditure, X. The second major analysis uses RAV vs. X maps to identify that subset (portfolio) of areas that maximizes the RAV of the firm's multiyear exploration budget. The IWS, which is demonstrated numerically, consists of six components based on the geologic description of a hypothetical basin and project area (PA) and a mix of hypothetical and actual conditions of an unidentified area. The geology is quantified and processed by Bayesian belief networks to produce the geology-based inputs required by the IWS. An exploration investment of $60 M produced a highly skewed distribution of net present value (NPV), having mean and median values of $4,160 M and $139 M, respectively. For hypothetical mining firm Minex, the RAV of the exploration investment of $60 M is only $110.7 M. An RAV that is less than 3% of mean NPV reflects the aversion by Minex to risk as well as the magnitude of risk implicit to the highly skewed NPV distribution and the probability of 0.45 for capital loss. Potential benefits of initiating exploration of a portfolio of areas, as contrasted with one area, include increased marginal productivity of exploration as well as reduced probability for nondiscovery. For an exogenously determined multiyear exploration budget, a conceptual framework for portfolio optimization is developed based on marginal RAV exploration products for candidate PAs. PORTFOLIO, a software developed to implement optimization, allocates exploration to PAs so that the RAV of the exploration budget is maximized. Moreover, PORTFOLIO provides a means to examine the impact of magnitude of budget on the composition of the exploration portfolio and the optimum allocation of exploration to PAs that comprise the portfolio. Using fictitious data for five PAs, a numerical demonstration is provided of the use of PORTFOLIO to identify those PAs that comprise the optimum exploration portfolio and to optimally allocate the multiyear budget across portfolio PAs.

  2. Telerobotic system concept for real-time soft-tissue imaging during radiotherapy beam delivery

    SciTech Connect (OSTI)

    Schlosser, Jeffrey; Salisbury, Kenneth; Hristov, Dimitre [Department of Mechanical Engineering, Stanford University, Stanford, California 94305 (United States); Department of Computer Science and Department of Surgery, Stanford University, Stanford, California 94305 (United States); Department of Radiation Oncology, Stanford University, Stanford, California 94305 (United States)

    2010-12-15T23:59:59.000Z

    Purpose: The curative potential of external beam radiation therapy is critically dependent on having the ability to accurately aim radiation beams at intended targets while avoiding surrounding healthy tissues. However, existing technologies are incapable of real-time, volumetric, soft-tissue imaging during radiation beam delivery, when accurate target tracking is most critical. The authors address this challenge in the development and evaluation of a novel, minimally interfering, telerobotic ultrasound (U.S.) imaging system that can be integrated with existing medical linear accelerators (LINACs) for therapy guidance. Methods: A customized human-safe robotic manipulator was designed and built to control the pressure and pitch of an abdominal U.S. transducer while avoiding LINAC gantry collisions. A haptic device was integrated to remotely control the robotic manipulator motion and U.S. image acquisition outside the LINAC room. The ability of the system to continuously maintain high quality prostate images was evaluated in volunteers over extended time periods. Treatment feasibility was assessed by comparing a clinically deployed prostate treatment plan to an alternative plan in which beam directions were restricted to sectors that did not interfere with the transabdominal U.S. transducer. To demonstrate imaging capability concurrent with delivery, robot performance and U.S. target tracking in a phantom were tested with a 15 MV radiation beam active. Results: Remote image acquisition and maintenance of image quality with the haptic interface was successfully demonstrated over 10 min periods in representative treatment setups of volunteers. Furthermore, the robot's ability to maintain a constant probe force and desired pitch angle was unaffected by the LINAC beam. For a representative prostate patient, the dose-volume histogram (DVH) for a plan with restricted sectors remained virtually identical to the DVH of a clinically deployed plan. With reduced margins, as would be enabled by real-time imaging, gross tumor volume coverage was identical while notable reductions of bladder and rectal volumes exposed to large doses were possible. The quality of U.S. images obtained during beam operation was not appreciably degraded by radiofrequency interference and 2D tracking of a phantom object in U.S. images obtained with the beam on/off yielded no significant differences. Conclusions: Remotely controlled robotic U.S. imaging is feasible in the radiotherapy environment and for the first time may offer real-time volumetric soft-tissue guidance concurrent with radiotherapy delivery.

  3. Evolving treatment plan quality criteria from institution-specific experience

    SciTech Connect (OSTI)

    Ruan, D.; Shao, W.; DeMarco, J.; Tenn, S.; King, C.; Low, D.; Kupelian, P.; Steinberg, M. [Department of Radiation Oncology, University of California, Los Angeles, California 90095 (United States)

    2012-05-15T23:59:59.000Z

    Purpose: The dosimetric aspects of radiation therapy treatment plan quality are usually evaluated and reported with dose volume histogram (DVH) endpoints. For clinical practicality, a small number of representative quantities derived from the DVH are often used as dose endpoints to summarize the plan quality. National guidelines on reference values for such quantities for some standard treatment approaches are often used as acceptance criteria to trigger treatment plan review. On the other hand, treatment prescription and planning approaches specific to each institution warrants the need to report plan quality in terms of practice consistency and with respect to institution-specific experience. The purpose of this study is to investigate and develop a systematic approach to record and characterize the institution-specific plan experience and use such information to guide the design of plan quality criteria. In the clinical setting, this approach will assist in (1) improving overall plan quality and consistency and (2) detecting abnormal plan behavior for retrospective analysis. Methods: The authors propose a self-evolving methodology and have developed an in-house prototype software suite that (1) extracts the dose endpoints from a treatment plan and evaluates them against both national standard and institution-specific criteria and (2) evolves the statistics for the dose endpoints and updates institution-specific criteria. Results: The validity of the proposed methodology was demonstrated with a database of prostate stereotactic body radiotherapy cases. As more data sets are accumulated, the evolving institution-specific criteria can serve as a reliable and stable consistency measure for plan quality and reveals the potential use of the ''tighter'' criteria than national standards or projected criteria, leading to practice that may push to shrink the gap between plans deemed acceptable and the underlying unknown optimality. Conclusions: The authors have developed a rationale to improve plan quality and consistency, by evolving the plan quality criteria from institution-specific experience, complementary to national standards. The validity of the proposed method was demonstrated with a prototype system on prostate stereotactic body radiotherapy (SBRT) cases. The current study uses direct and indirect DVH endpoints for plan quality evaluation, but the infrastructure proposed here applies to general outcome data as well. The authors expect forward evaluation together with intelligent update based on evidence-based learning, which will evolve the clinical practice for improved efficiency, consistency, and ultimately better treatment outcome.

  4. FDG-PET Assessment of the Effect of Head and Neck Radiotherapy on Parotid Gland Glucose Metabolism

    SciTech Connect (OSTI)

    Roach, Michael C. [School of Medicine, Duke University Medical Center, Duke University, Durham, NC (United States); Turkington, Timothy G. [Department of Radiology, Duke University Medical Center, Duke University, Durham, NC (United States); Department of Biomedical Engineering, Duke University Medical Center, Duke University, Durham, NC (United States); Higgins, Kristin A. [Department of Radiation Oncology, Duke University Medical Center, Duke University, Durham, NC (United States); Hawk, Thomas C. [Department of Radiology, Duke University Medical Center, Duke University, Durham, NC (United States); Hoang, Jenny K. [Department of Radiology, Duke University Medical Center, Duke University, Durham, NC (United States); Department of Radiation Oncology, Duke University Medical Center, Duke University, Durham, NC (United States); Brizel, David M., E-mail: david.brizel@duke.edu [Department of Radiation Oncology, Duke University Medical Center, Duke University, Durham, NC (United States); Department of Surgery, Duke University Medical Center, Duke University, Durham, NC (United States)

    2012-01-01T23:59:59.000Z

    Purpose: Functional imaging with [F-18]-fluorodeoxyglucose positron emission tomography (FDG-PET) provides the opportunity to define the physiology of the major salivary glands before and after radiation therapy. The goal of this retrospective study was to identify the radiation dose-response relationship of parotid gland glucose metabolism in patients with head and neck squamous cell carcinoma (HNSCC). Materials and Methods: Forty-nine adults with HNSCC were identified who had curative intent intensity-modulated radiation therapy (IMRT) and FDG-PET imaging before and after treatment. Using a graphical user interface, contours were delineated for the parotid glands on axial CT slices while all authors were blinded to paired PET slices. Average and maximal standard uptake values (SUV) were measured within these anatomic regions. Changes in SUV and volume after radiation therapy were correlated with parotid gland dose-volume histograms from IMRT plans. Results: The average parotid gland volume was 30.7 mL and contracted 3.9 {+-} 1.9% with every increase of 10 Gy in mean dose (p = 0.04). However, within the first 3 months after treatment, there was a uniform reduction of 16.5% {+-} 7.3% regardless of dose. The average SUV{sub mean} of the glands was 1.63 {+-} 0.48 pretreatment and declined by 5.2% {+-} 2.5% for every increase of 10 Gy in mean dose (p = 0.04). The average SUV{sub max} was 4.07 {+-} 2.85 pretreatment and decreased in a sigmoid manner with mean dose. A threshold of 32 Gy for mean dose existed, after which SUV{sub max} declined rapidly. Conclusion: Radiation dose responses of the parotid glands can be measured by integrated CT/FDG-PET scans. Retrospective analysis showed sigmoidal declines in the maximum metabolism but linear declines in the average metabolism of the glands with dose. Future studies should correlate this decline in FDG uptake with saliva production to improve treatment planning.

  5. Normal Tissue Complication Probability Modeling of Radiation-Induced Hypothyroidism After Head-and-Neck Radiation Therapy

    SciTech Connect (OSTI)

    Bakhshandeh, Mohsen [Department of Medical Physics, Faculty of Medical Sciences, Tarbiat Modares University, Tehran (Iran, Islamic Republic of)] [Department of Medical Physics, Faculty of Medical Sciences, Tarbiat Modares University, Tehran (Iran, Islamic Republic of); Hashemi, Bijan, E-mail: bhashemi@modares.ac.ir [Department of Medical Physics, Faculty of Medical Sciences, Tarbiat Modares University, Tehran (Iran, Islamic Republic of)] [Department of Medical Physics, Faculty of Medical Sciences, Tarbiat Modares University, Tehran (Iran, Islamic Republic of); Mahdavi, Seied Rabi Mehdi [Department of Medical Physics, Faculty of Medical Sciences, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of)] [Department of Medical Physics, Faculty of Medical Sciences, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of); Nikoofar, Alireza; Vasheghani, Maryam [Department of Radiation Oncology, Hafte-Tir Hospital, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of)] [Department of Radiation Oncology, Hafte-Tir Hospital, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of); Kazemnejad, Anoshirvan [Department of Biostatistics, Faculty of Medical Sciences, Tarbiat Modares University, Tehran (Iran, Islamic Republic of)] [Department of Biostatistics, Faculty of Medical Sciences, Tarbiat Modares University, Tehran (Iran, Islamic Republic of)

    2013-02-01T23:59:59.000Z

    Purpose: To determine the dose-response relationship of the thyroid for radiation-induced hypothyroidism in head-and-neck radiation therapy, according to 6 normal tissue complication probability models, and to find the best-fit parameters of the models. Methods and Materials: Sixty-five patients treated with primary or postoperative radiation therapy for various cancers in the head-and-neck region were prospectively evaluated. Patient serum samples (tri-iodothyronine, thyroxine, thyroid-stimulating hormone [TSH], free tri-iodothyronine, and free thyroxine) were measured before and at regular time intervals until 1 year after the completion of radiation therapy. Dose-volume histograms (DVHs) of the patients' thyroid gland were derived from their computed tomography (CT)-based treatment planning data. Hypothyroidism was defined as increased TSH (subclinical hypothyroidism) or increased TSH in combination with decreased free thyroxine and thyroxine (clinical hypothyroidism). Thyroid DVHs were converted to 2 Gy/fraction equivalent doses using the linear-quadratic formula with {alpha}/{beta} = 3 Gy. The evaluated models included the following: Lyman with the DVH reduced to the equivalent uniform dose (EUD), known as LEUD; Logit-EUD; mean dose; relative seriality; individual critical volume; and population critical volume models. The parameters of the models were obtained by fitting the patients' data using a maximum likelihood analysis method. The goodness of fit of the models was determined by the 2-sample Kolmogorov-Smirnov test. Ranking of the models was made according to Akaike's information criterion. Results: Twenty-nine patients (44.6%) experienced hypothyroidism. None of the models was rejected according to the evaluation of the goodness of fit. The mean dose model was ranked as the best model on the basis of its Akaike's information criterion value. The D{sub 50} estimated from the models was approximately 44 Gy. Conclusions: The implemented normal tissue complication probability models showed a parallel architecture for the thyroid. The mean dose model can be used as the best model to describe the dose-response relationship for hypothyroidism complication.

  6. Multicriteria optimization informed VMAT planning

    SciTech Connect (OSTI)

    Chen, Huixiao; Craft, David L.; Gierga, David P., E-mail: dgierga@partners.org

    2014-04-01T23:59:59.000Z

    We developed a patient-specific volumetric-modulated arc therapy (VMAT) optimization procedure using dose-volume histogram (DVH) information from multicriteria optimization (MCO) of intensity-modulated radiotherapy (IMRT) plans. The study included 10 patients with prostate cancer undergoing standard fractionation treatment, 10 patients with prostate cancer undergoing hypofractionation treatment, and 5 patients with head/neck cancer. MCO-IMRT plans using 20 and 7 treatment fields were generated for each patient on the RayStation treatment planning system (clinical version 2.5, RaySearch Laboratories, Stockholm, Sweden). The resulting DVH of the 20-field MCO-IMRT plan for each patient was used as the reference DVH, and the extracted point values of the resulting DVH of the MCO-IMRT plan were used as objectives and constraints for VMAT optimization. Weights of objectives or constraints of VMAT optimization or both were further tuned to generate the best match with the reference DVH of the MCO-IMRT plan. The final optimal VMAT plan quality was evaluated by comparison with MCO-IMRT plans based on homogeneity index, conformity number of planning target volume, and organ at risk sparing. The influence of gantry spacing, arc number, and delivery time on VMAT plan quality for different tumor sites was also evaluated. The resulting VMAT plan quality essentially matched the 20-field MCO-IMRT plan but with a shorter delivery time and less monitor units. VMAT plan quality of head/neck cancer cases improved using dual arcs whereas prostate cases did not. VMAT plan quality was improved by fine gantry spacing of 2 for the head/neck cancer cases and the hypofractionation-treated prostate cancer cases but not for the standard fractionation–treated prostate cancer cases. MCO-informed VMAT optimization is a useful and valuable way to generate patient-specific optimal VMAT plans, though modification of the weights of objectives or constraints extracted from resulting DVH of MCO-IMRT or both is necessary.

  7. A study on planning organ at risk volume for the rectum using cone beam computed tomography in the treatment of prostate cancer

    SciTech Connect (OSTI)

    Prabhakar, Ramachandran, E-mail: Ramachandran.Prabhakar@petermac.org [Department of Physical Sciences, Peter MacCallum Cancer Centre, Melbourne, Victoria (Australia); RMIT University, Melbourne (Australia); Oates, Richard; Jones, Daryl [Radiation Therapy Services, Peter MacCallum Cancer Centre, Melbourne (Australia); Kron, Tomas [Department of Physical Sciences, Peter MacCallum Cancer Centre, Melbourne, Victoria (Australia); RMIT University, Melbourne (Australia); Cramb, Jim [Department of Physical Sciences, Peter MacCallum Cancer Centre, Melbourne, Victoria (Australia); Foroudi, Farshad [Radiation Therapy Services, Peter MacCallum Cancer Centre, Melbourne (Australia); Geso, Moshi [RMIT University, Melbourne (Australia); Gill, Suki [Radiation Therapy Services, Peter MacCallum Cancer Centre, Melbourne (Australia)

    2014-04-01T23:59:59.000Z

    In this study, we analyzed planning organ at risk volume (PRV) for the rectum using a series of cone beam computed tomographies (CBCTs) acquired during the treatment of prostate cancer and evaluated the dosimetric effect of different PRV definitions. Overall, 21 patients with prostate cancer were treated radically with 78 Gy in 39 fractions had in total 418 CBCTs, each acquired at the end of the first 5 fractions and then every alternate fraction. The PRV was generated from the Boolean sum volume of the rectum obtained from first 5 fractions (PRV-CBCT-5) and from all CBCTs (PRV-CBCT-All). The PRV margin was compared at the superior, middle, and inferior slices of the contoured rectum to compare PRV-CBCT-5 and PRV-CBCT-All. We also compared the dose received by the planned rectum (Rectum-computed tomography [CT]), PRV-CBCT-5, PRV-CBCT-All, and average rectum (CBCT-AV-dose-volume histogram [DVH]) at critical dose levels. The average measured rectal volume for all 21 patients for Rectum-CT, PRV-CBCT-5, and PRV-CBCT-All was 44.3 ± 15.0, 92.8 ± 40.40, and 121.5 ± 36.7 cm{sup 3}, respectively. For PRV-CBCT-All, the mean ± standard deviation displacement in the anterior, posterior, right, and left lateral directions in centimeters was 2.1 ± 1.1, 0.9 ± 0.5, 0.9 ± 0.8, and 1.1 ± 0.7 for the superior rectum; 0.8 ± 0.5, 1.1 ± 0.5, 1.0 ± 0.5, and 1.0 ± 0.5 for the middle rectum; and 0.3 ± 0.3; 0.9 ± 0.5; 0.4 ± 0.2, and 0.5 ± 0.3 for the inferior rectum, respectively. The first 5 CBCTs did not predict the PRV for individual patients. Our study shows that the PRV margin is different for superior, middle, and the inferior parts of the rectum, it is wider superiorly and narrower inferiorly. A uniform PRV margin does not represent the actual rectal variations during treatment for all treatment fractions. The large variation in interpatient rectal size implies a potential role for adaptive radiotherapy for prostate cancer.

  8. Early-Stage Breast Cancer Treated With 3-Week Accelerated Whole-Breast Radiation Therapy and Concomitant Boost

    SciTech Connect (OSTI)

    Chadha, Manjeet, E-mail: MChadha@chpnet.org [Department of Radiation Oncology, Beth Israel Medical Center, New York, New York (United States)] [Department of Radiation Oncology, Beth Israel Medical Center, New York, New York (United States); Woode, Rudolph; Sillanpaa, Jussi [Department of Radiation Oncology, Beth Israel Medical Center, New York, New York (United States)] [Department of Radiation Oncology, Beth Israel Medical Center, New York, New York (United States); Lucido, David [Department of Biostatistics, Beth Israel Medical Center, New York, New York (United States)] [Department of Biostatistics, Beth Israel Medical Center, New York, New York (United States); Boolbol, Susan K.; Kirstein, Laurie; Osborne, Michael P.; Feldman, Sheldon [Division of Breast Surgery, Beth Israel Medical Center, New York, New York (United States)] [Division of Breast Surgery, Beth Israel Medical Center, New York, New York (United States); Harrison, Louis B. [Department of Radiation Oncology, Beth Israel Medical Center, New York, New York (United States)] [Department of Radiation Oncology, Beth Israel Medical Center, New York, New York (United States)

    2013-05-01T23:59:59.000Z

    Purpose: To report early outcomes of accelerated whole-breast radiation therapy with concomitant boost. Methods and Materials: This is a prospective, institutional review board-approved study. Eligibility included stage TisN0, T1N0, and T2N0 breast cancer. Patients receiving adjuvant chemotherapy were ineligible. The whole breast received 40.5 Gy in 2.7-Gy fractions with a concomitant lumpectomy boost of 4.5 Gy in 0.3-Gy fractions. Total dose to the lumpectomy site was 45 Gy in 15 fractions over 19 days. Results: Between October 2004 and December 2010, 160 patients were treated; stage distribution was as follows: TisN0, n=63; T1N0, n=88; and T2N0, n=9. With a median follow-up of 3.5 years (range, 1.5-7.8 years) the 5-year overall survival and disease-free survival rates were 90% (95% confidence interval [CI] 0.84-0.94) and 97% (95% CI 0.93-0.99), respectively. Five-year local relapse-free survival was 99% (95% CI 0.96-0.99). Acute National Cancer Institute/Common Toxicity Criteria grade 1 and 2 skin toxicity was observed in 70% and 5%, respectively. Among the patients with ?2-year follow-up no toxicity higher than grade 2 on the Late Effects in Normal Tissues–Subjective, Objective, Management, and Analytic scale was observed. Review of the radiation therapy dose–volume histogram noted that ?95% of the prescribed dose encompassed the lumpectomy target volume in >95% of plans. The median dose received by the heart D{sub 05} was 215 cGy, and median lung V{sub 20} was 7.6%. Conclusions: The prescribed accelerated schedule of whole-breast radiation therapy with concomitant boost can be administered, achieving acceptable dose distribution. With follow-up to date, the results are encouraging and suggest minimal side effects and excellent local control.

  9. 4D analysis of influence of patient movement and anatomy alteration on the quality of 3D U/S-based prostate HDR brachytherapy treatment delivery

    SciTech Connect (OSTI)

    Milickovic, Natasa; Mavroidis, Panayiotis; Tselis, Nikolaos; Nikolova, Iliyana; Katsilieri, Zaira; Kefala, Vasiliki; Zamboglou, Nikolaos; Baltas, Dimos [Department of Medical Physics and Engineering, Offenbach Clinic, Starkenburgring 66, 63069 Offenbach am Main (Germany); Department of Medical Radiation Physics, Karolinska Institutet and Stockholm University (Sweden); Department of Radiation Oncology, Offenbach Clinic, Starkenburgring 66, 63069 Offenbach am Main (Germany); Department of Medical Physics and Engineering, Offenbach Clinic, Starkenburgring 66, 63069 Offenbach am Main (Germany); Department of Radiation Oncology, Offenbach Clinic, Starkenburgring 66, 63069 Offenbach am Main (Germany); Department of Medical Physics and Engineering, Offenbach Clinic, Starkenburgring 66, 63069 Offenbach am Main, Germany and Nuclear and Particle Physics Section, Physics Department, University of Athens, 15771 Athens (Greece)

    2011-09-15T23:59:59.000Z

    Purpose: Modern HDR brachytherapy treatment for prostate cancer based on the 3D ultrasound (U/S) plays increasingly important role. The purpose of this study is to investigate possible patient movement and anatomy alteration between the clinical image set acquisition, made after the needle implantation, and the patient irradiation and their influence on the quality of treatment. Methods: The authors used 3D U/S image sets and the corresponding treatment plans based on a 4D-treatment planning procedure: plans of 25 patients are obtained right after the needle implantation (clinical plan is based on this 3D image set) and just before and after the treatment delivery. The authors notice the slight decrease of treatment quality with increase of time gap between the clinical image set acquisition and the patient irradiation. 4D analysis of dose-volume-histograms (DVHs) for prostate: CTV1 = PTV, and urethra, rectum, and bladder as organs at risk (OARs) and conformity index (COIN) is presented, demonstrating the effect of prostate, OARs, and needles displacement. Results: The authors show that in the case that the patient body movement/anatomy alteration takes place, this results in modification of DVHs and radiobiological parameters, hence the plan quality. The observed average displacement of needles (1 mm) and of prostate (0.57 mm) is quite small as compared with the average displacement noted in several other reports [A. A. Martinez et al., Int. J. Radiat. Oncol., Biol., Phys. 49(1), 61-69 (2001); S. J. Damore et al., Int. J. Radiat. Oncol., Biol., Phys. 46(5), 1205-1211 (2000); P. J. Hoskin et al., Radiotherm. Oncol. 68(3), 285-288 (2003); E. Mullokandov et al., Int. J. Radiat. Oncol., Biol., Phys. 58(4), 1063-1071 (2004)] in the literature. Conclusions: Although the decrease of quality of dosimetric and radiobiological parameters occurs, this does not cause clinically unacceptable changes to the 3D dose distribution, according to our clinical protocol.

  10. Metallic artifact mitigation and organ-constrained tissue assignment for Monte Carlo calculations of permanent implant lung brachytherapy

    SciTech Connect (OSTI)

    Sutherland, J. G. H.; Miksys, N.; Thomson, R. M., E-mail: rthomson@physics.carleton.ca [Carleton Laboratory for Radiotherapy Physics, Department of Physics, Carleton University, Ottawa, Ontario K1S 5B6 (Canada); Furutani, K. M. [Department of Radiation Oncology, Mayo Clinic College of Medicine, Rochester, Minnesota 55905 (United States)] [Department of Radiation Oncology, Mayo Clinic College of Medicine, Rochester, Minnesota 55905 (United States)

    2014-01-15T23:59:59.000Z

    Purpose: To investigate methods of generating accurate patient-specific computational phantoms for the Monte Carlo calculation of lung brachytherapy patient dose distributions. Methods: Four metallic artifact mitigation methods are applied to six lung brachytherapy patient computed tomography (CT) images: simple threshold replacement (STR) identifies high CT values in the vicinity of the seeds and replaces them with estimated true values; fan beam virtual sinogram replaces artifact-affected values in a virtual sinogram and performs a filtered back-projection to generate a corrected image; 3D median filter replaces voxel values that differ from the median value in a region of interest surrounding the voxel and then applies a second filter to reduce noise; and a combination of fan beam virtual sinogram and STR. Computational phantoms are generated from artifact-corrected and uncorrected images using several tissue assignment schemes: both lung-contour constrained and unconstrained global schemes are considered. Voxel mass densities are assigned based on voxel CT number or using the nominal tissue mass densities. Dose distributions are calculated using the EGSnrc user-code BrachyDose for{sup 125}I, {sup 103}Pd, and {sup 131}Cs seeds and are compared directly as well as through dose volume histograms and dose metrics for target volumes surrounding surgical sutures. Results: Metallic artifact mitigation techniques vary in ability to reduce artifacts while preserving tissue detail. Notably, images corrected with the fan beam virtual sinogram have reduced artifacts but residual artifacts near sources remain requiring additional use of STR; the 3D median filter removes artifacts but simultaneously removes detail in lung and bone. Doses vary considerably between computational phantoms with the largest differences arising from artifact-affected voxels assigned to bone in the vicinity of the seeds. Consequently, when metallic artifact reduction and constrained tissue assignment within lung contours are employed in generated phantoms, this erroneous assignment is reduced, generally resulting in higher doses. Lung-constrained tissue assignment also results in increased doses in regions of interest due to a reduction in the erroneous assignment of adipose to voxels within lung contours. Differences in dose metrics calculated for different computational phantoms are sensitive to radionuclide photon spectra with the largest differences for{sup 103}Pd seeds and smallest but still considerable differences for {sup 131}Cs seeds. Conclusions: Despite producing differences in CT images, dose metrics calculated using the STR, fan beam + STR, and 3D median filter techniques produce similar dose metrics. Results suggest that the accuracy of dose distributions for permanent implant lung brachytherapy is improved by applying lung-constrained tissue assignment schemes to metallic artifact corrected images.

  11. Bilateral implant reconstruction does not affect the quality of postmastectomy radiation therapy

    SciTech Connect (OSTI)

    Ho, Alice Y., E-mail: hoa1234@mskcc.org [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, NY (United States); Patel, Nisha [Drexel University College of Medicine, Philadelphia, PA (United States); Ohri, Nisha [Department of Radiation Oncology, Mount Sinai School of Medicine, New York, NY (United States); Morrow, Monica [Department of Surgery, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Mehrara, Babak J.; Disa, Joseph J.; Cordeiro, Peter G. [Department of Plastic Surgery, Memorial Sloan-Kettering Cancer Center, New York, NY (United States); Shi, Weiji; Zhang, Zhigang [Department of Biostatistics and Epidemiology, Memorial Sloan-Kettering Cancer Center, New York, NY (United States); Gelblum, Daphna [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, NY (United States); Nerbun, Claire T.; Woch, Katherine M.; Ballangrud, Ase [Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, NY (United States); McCormick, Beryl; Powell, Simon N. [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, NY (United States)

    2014-04-01T23:59:59.000Z

    To determine if the presence of bilateral implants, in addition to other anatomic and treatment-related variables, affects coverage of the target volume and dose to the heart and lung in patients receiving postmastectomy radiation therapy (PMRT). A total of 197 consecutive women with breast cancer underwent mastectomy and immediate tissue expander (TE) placement, with or without exchange for a permanent implant (PI) before radiation therapy at our center. PMRT was delivered with 2 tangential beams + supraclavicular lymph node field (50 Gy). Patients were grouped by implant number: 51% unilateral (100) and 49% bilateral (97). The planning target volume (PTV) (defined as implant + chest wall + nodes), heart, and ipsilateral lung were contoured and the following parameters were abstracted from dose-volume histogram (DVH) data: PTV D{sub 95%} > 98%, Lung V{sub 20}Gy > 30%, and Heart V{sub 25}Gy > 5%. Univariate (UVA) and multivariate analyses (MVA) were performed to determine the association of variables with these parameters. The 2 groups were well balanced for implant type and volume, internal mammary node (IMN) treatment, and laterality. In the entire cohort, 90% had PTV D{sub 95%} > 98%, indicating excellent coverage of the chest wall. Of the patients, 27% had high lung doses (V{sub 20}Gy > 30%) and 16% had high heart doses (V{sub 25}Gy > 5%). No significant factors were associated with suboptimal PTV coverage. On MVA, IMN treatment was found to be highly associated with high lung and heart doses (both p < 0.0001), but implant number was not (p = 0.54). In patients with bilateral implants, IMN treatment was the only predictor of dose to the contralateral implant (p = 0.001). In conclusion, bilateral implants do not compromise coverage of the target volume or increase lung and heart dose in patients receiving PMRT. The most important predictor of high lung and heart doses in patients with implant-based reconstruction, whether unilateral or bilateral, is treatment of the IMNs. Refinement of radiation techniques in reconstructed patients who require comprehensive nodal irradiation is warranted.

  12. Volumetric-modulated arc therapy (RapidArc) vs. conventional fixed-field intensity-modulated radiotherapy for {sup 18}F-FDG-PET-guided dose escalation in oropharyngeal cancer: A planning study

    SciTech Connect (OSTI)

    Teoh, May, E-mail: m.teoh@nhs.net [Department of Oncology, St. Luke's Cancer Centre, Royal Surrey County Hospital, Guildford, Surrey (United Kingdom); Beveridge, Sabeena [Department of Medical Physics, St. Luke's Cancer Centre, Royal Surrey County Hospital, Guildford, Surrey (United Kingdom); Wood, Katie; Whitaker, Stephen [Department of Oncology, St. Luke's Cancer Centre, Royal Surrey County Hospital, Guildford, Surrey (United Kingdom); Adams, Elizabeth; Rickard, Donna; Jordan, Tom; Nisbet, Andrew [Department of Medical Physics, St. Luke's Cancer Centre, Royal Surrey County Hospital, Guildford, Surrey (United Kingdom); Clark, Catharine H. [Department of Medical Physics, St. Luke's Cancer Centre, Royal Surrey County Hospital, Guildford, Surrey (United Kingdom); National Physical Laboratory, Hampton Road, Teddington, Middlesex (United Kingdom)

    2013-04-01T23:59:59.000Z

    Fluorine-18-fluorodeoxyglucose-positron emission tomography ({sup 18}F-FDG-PET)–guided focal dose escalation in oropharyngeal cancer may potentially improve local control. We evaluated the feasibility of this approach using volumetric-modulated arc therapy (RapidArc) and compared these plans with fixed-field intensity-modulated radiotherapy (IMRT) focal dose escalation plans. Materials and methods: An initial study of 20 patients compared RapidArc with fixed-field IMRT using standard dose prescriptions. From this cohort, 10 were included in a dose escalation planning study. Dose escalation was applied to {sup 18}F-FDG-PET–positive regions in the primary tumor at dose levels of 5% (DL1), 10% (DL2), and 15% (DL3) above standard radical dose (65 Gy in 30 fractions). Fixed-field IMRT and double-arc RapidArc plans were generated for each dataset. Dose-volume histograms were used for plan evaluation and comparison. The Paddick conformity index (CI{sub Paddick}) and monitor units (MU) for each plan were recorded and compared. Both IMRT and RapidArc produced clinically acceptable plans and achieved planning objectives for target volumes. Dose conformity was significantly better in the RapidArc plans, with lower CI{sub Paddick} scores in both primary (PTV1) and elective (PTV2) planning target volumes (largest difference in PTV1 at DL3; 0.81 ± 0.03 [RapidArc] vs. 0.77 ± 0.07 [IMRT], p = 0.04). Maximum dose constraints for spinal cord and brainstem were not exceeded in both RapidArc and IMRT plans, but mean doses were higher with RapidArc (by 2.7 ± 1 Gy for spinal cord and 1.9 ± 1 Gy for brainstem). Contralateral parotid mean dose was lower with RapidArc, which was statistically significant at DL1 (29.0 vs. 29.9 Gy, p = 0.01) and DL2 (29.3 vs. 30.3 Gy, p = 0.03). MU were reduced by 39.8–49.2% with RapidArc (largest difference at DL3, 641 ± 94 vs. 1261 ± 118, p < 0.01). {sup 18}F-FDG-PET–guided focal dose escalation in oropharyngeal cancer is feasible with RapidArc. Compared with conventional fixed-field IMRT, RapidArc can achieve better dose conformity, improve contralateral parotid sparing, and uses fewer MU.

  13. Permanent Breast Seed Implant Dosimetry Quality Assurance

    SciTech Connect (OSTI)

    Keller, Brian M., E-mail: Brian.Keller@sunnybrook.ca [Department of Medical Physics, Sunnybrook Health Sciences Center, Toronto, ON (Canada); Department of Radiation Oncology, University of Toronto, Sunnybrook Health Sciences Center, Toronto, ON (Canada); Ravi, Ananth [Department of Medical Physics, Sunnybrook Health Sciences Center, Toronto, ON (Canada); Sankreacha, Raxa [Carlo Fidani Regional Cancer Center, Mississauga, ON (Canada); Pignol, Jean-Philippe [Department of Radiation Oncology, University of Toronto, Sunnybrook Health Sciences Center, Toronto, ON (Canada)

    2012-05-01T23:59:59.000Z

    Purpose: A permanent breast seed implant is a novel method of accelerated partial breast irradiation for women with early-stage breast cancer. This article presents pre- and post-implant dosimetric data, relates these data to clinical outcomes, and makes recommendations for those interested in starting a program. Methods and Materials: A total of 95 consecutive patients were accrued into one of three clinical trials after breast-conserving surgery: a Phase I/II trial (67 patients with infiltrating ductal carcinoma); a Phase II registry trial (25 patients with infiltrating ductal carcinoma); or a multi-center Phase II trial for patients with ductal carcinoma in situ (3 patients). Contouring of the planning target volume (PTV) was done on a Pinnacle workstation and dosimetry calculations, including dose-volume histograms, were done using a Variseed planning computer. Results: The mean pre-implant PTV coverage for the V{sub 90}, V{sub 100}, V{sub 150}, and V{sub 200} were as follows: 98.8% {+-} 1.2% (range, 94.5-100%); 97.3% {+-} 2.1% (range, 90.3-99.9%), 68.8% {+-} 14.3% (range, 32.7-91.5%); and 27.8% {+-} 8.6% (range, 15.1-62.3%). The effect of seed motion was characterized by post-implant dosimetry performed immediately after the implantation (same day) and at 2 months after the implantation. The mean V{sub 100} changed from 85.6% to 88.4% (p = 0.004) and the mean V{sub 200} changed from 36.2% to 48.3% (p < 0.001). Skin toxicity was associated with maximum skin dose (p = 0.014). Conclusions: Preplanning dosimetry should aim for a V{sub 90} of approximately 100%, a V{sub 100} between 95% and 100%, and a V{sub 200} between 20% and 30%, as these numbers are associated with no local recurrences to date and good patient tolerance. In general, the target volume coverage improved over the duration of the seed therapy. The maximum skin dose, defined as the average dose over the hottest 1 Multiplication-Sign 1-cm{sup 2} surface area, should be limited to 90% of the prescription dose to minimize delayed skin toxicity.

  14. MRI-based treatment planning with pseudo CT generated through atlas registration

    SciTech Connect (OSTI)

    Uh, Jinsoo, E-mail: jinsoo.uh@stjude.org; Merchant, Thomas E.; Hua, Chiaho [Department of Radiological Sciences, St. Jude Children's Research Hospital, Memphis, Tennessee 38105 (United States)] [Department of Radiological Sciences, St. Jude Children's Research Hospital, Memphis, Tennessee 38105 (United States); Li, Yimei; Li, Xingyu [Department of Biostatistics, St. Jude Children's Research Hospital, Memphis, Tennessee 38105 (United States)] [Department of Biostatistics, St. Jude Children's Research Hospital, Memphis, Tennessee 38105 (United States)

    2014-05-15T23:59:59.000Z

    Purpose: To evaluate the feasibility and accuracy of magnetic resonance imaging (MRI)-based treatment planning using pseudo CTs generated through atlas registration. Methods: A pseudo CT, providing electron density information for dose calculation, was generated by deforming atlas CT images previously acquired on other patients. The authors tested 4 schemes of synthesizing a pseudo CT from single or multiple deformed atlas images: use of a single arbitrarily selected atlas, arithmetic mean process using 6 atlases, and pattern recognition with Gaussian process (PRGP) using 6 or 12 atlases. The required deformation for atlas CT images was derived from a nonlinear registration of conjugated atlas MR images to that of the patient of interest. The contrasts of atlas MR images were adjusted by histogram matching to reduce the effect of different sets of acquisition parameters. For comparison, the authors also tested a simple scheme assigning the Hounsfield unit of water to the entire patient volume. All pseudo CT generating schemes were applied to 14 patients with common pediatric brain tumors. The image similarity of real patient-specific CT and pseudo CTs constructed by different schemes was compared. Differences in computation times were also calculated. The real CT in the treatment planning system was replaced with the pseudo CT, and the dose distribution was recalculated to determine the difference. Results: The atlas approach generally performed better than assigning a bulk CT number to the entire patient volume. Comparing atlas-based schemes, those using multiple atlases outperformed the single atlas scheme. For multiple atlas schemes, the pseudo CTs were similar to the real CTs (correlation coefficient, 0.787–0.819). The calculated dose distribution was in close agreement with the original dose. Nearly the entire patient volume (98.3%–98.7%) satisfied the criteria of chi-evaluation (<2% maximum dose and 2 mm range). The dose to 95% of the volume and the percentage of volume receiving at least 95% of the prescription dose in the planning target volume differed from the original values by less than 2% of the prescription dose (root-mean-square, RMS < 1%). The PRGP scheme did not perform better than the arithmetic mean process with the same number of atlases. Increasing the number of atlases from 6 to 12 often resulted in improvements, but statistical significance was not always found. Conclusions: MRI-based treatment planning with pseudo CTs generated through atlas registration is feasible for pediatric brain tumor patients. The doses calculated from pseudo CTs agreed well with those from real CTs, showing dosimetric accuracy within 2% for the PTV when multiple atlases were used. The arithmetic mean process may be a reasonable choice over PRGP for the synthesis scheme considering performance and computational costs.

  15. Strategies for automatic online treatment plan reoptimization using clinical treatment planning system: A planning parameters study

    SciTech Connect (OSTI)

    Li, Taoran; Wu, Qiuwen; Zhang, You; Vergalasova, Irina; Lee, W. Robert; Yin, Fang-Fang; Wu, Q. Jackie [Duke Medical Physics Graduate Program, Duke University, Durham, North Carolina 27705 and Department of Radiation Oncology, Duke University Medical Center, Durham, North Carolina 27710 (United States)] [Duke Medical Physics Graduate Program, Duke University, Durham, North Carolina 27705 and Department of Radiation Oncology, Duke University Medical Center, Durham, North Carolina 27710 (United States)

    2013-11-15T23:59:59.000Z

    Purpose: Adaptive radiation therapy for prostate cancer using online reoptimization provides an improved control of interfractional anatomy variations. However, the clinical implementation of online reoptimization is currently limited by the low efficiency of current strategies and the difficulties associated with integration into the current treatment planning system. This study investigates the strategies for performing fast (?2 min) automatic online reoptimization with a clinical fluence-map-based treatment planning system; and explores the performance with different input parameters settings: dose-volume histogram (DVH) objective settings, starting stage, and iteration number (in the context of real time planning).Methods: Simulated treatments of 10 patients were reoptimized daily for the first week of treatment (5 fractions) using 12 different combinations of optimization strategies. Options for objective settings included guideline-based RTOG objectives, patient-specific objectives based on anatomy on the planning CT, and daily-CBCT anatomy-based objectives adapted from planning CT objectives. Options for starting stages involved starting reoptimization with and without the original plan's fluence map. Options for iteration numbers were 50 and 100. The adapted plans were then analyzed by statistical modeling, and compared both in terms of dosimetry and delivery efficiency.Results: All online reoptimized plans were finished within ?2 min with excellent coverage and conformity to the daily target. The three input parameters, i.e., DVH objectives, starting stage, and iteration number, contributed to the outcome of optimization nearly independently. Patient-specific objectives generally provided better OAR sparing compared to guideline-based objectives. The benefit in high-dose sparing from incorporating daily anatomy into objective settings was positively correlated with the relative change in OAR volumes from planning CT to daily CBCT. The use of the original plan fluence map as the starting stage reduced OAR dose at the mid-dose region, but increased the monitor units by 17%. Differences of only 2cc or less in OAR V50%/V70Gy/V76Gy were observed between 100 and 50 iterations.Conclusions: It is feasible to perform automatic online reoptimization in ?2 min using a clinical treatment planning system. Selecting optimal sets of input parameters is the key to achieving high quality reoptimized plans, and should be based on the individual patient's daily anatomy, delivery efficiency, and time allowed for plan adaptation.

  16. Helical tomotherapy with dynamic running-start-stop delivery compared to conventional tomotherapy delivery

    SciTech Connect (OSTI)

    Rong, Yi, E-mail: yi.rong@osumc.edu [Department of Radiation Oncology, The Ohio State University Wexner Medical Center, Columbus, Ohio 43210 (United States)] [Department of Radiation Oncology, The Ohio State University Wexner Medical Center, Columbus, Ohio 43210 (United States); Chen, Yu; Lu, Weiguo [21st Century Oncology, Madison, Wisconsin 53719 (United States)] [21st Century Oncology, Madison, Wisconsin 53719 (United States); Shang, Lu [Guangxi Polytechnic of Construction and Technology, Nanning (China)] [Guangxi Polytechnic of Construction and Technology, Nanning (China); Zuo, Li [Radiologic Sciences and Respiratory Therapy Division, School of Health and Rehabilitation Sciences, The Ohio State University College of Medicine, Columbus, Ohio 43210 (United States)] [Radiologic Sciences and Respiratory Therapy Division, School of Health and Rehabilitation Sciences, The Ohio State University College of Medicine, Columbus, Ohio 43210 (United States); Chen, Quan [Department of Radiation Oncology, University of Virginia, Charlottesville, Virginia 22904 (United States)] [Department of Radiation Oncology, University of Virginia, Charlottesville, Virginia 22904 (United States)

    2014-05-15T23:59:59.000Z

    Purpose: Despite superior target dose uniformity, helical tomotherapy{sup ®} (HT) may involve a trade-off between longitudinal dose conformity and beam-on time (BOT), due to the limitation of only three available jaw sizes with the conventional HT (1.0, 2.5, and 5.0 cm). The recently introduced dynamic running-start-stop (RSS) delivery allows smaller jaw opening at the superior and inferior ends of the target when a sharp penumbra is needed. This study compared the dosimetric performance of RSS delivery with the fixed jaw HT delivery. Methods: Twenty patient cases were selected and deidentified prior to treatment planning, including 16 common clinical cases (brain, head and neck (HN), lung, and prostate) and four special cases of whole brain with hippocampus avoidance (WBHA) that require a high degree of dose modulation. HT plans were generated for common clinical cases using the fixed 2.5 cm jaw width (HT2.5) and WBHA cases using 1.0 cm (HT1.0). The jaw widths for RSS were preset with a larger size (RSS5.0 vs HT2.5 and RSS2.5 vs HT1.0). Both delivery techniques were planned based on identical contours, prescriptions, and planning objectives. Dose indices for targets and critical organs were compared using dose-volume histograms, BOT, and monitor units. Results: The average BOT was reduced from 4.8 min with HT2.5 to 2.5 min with RSS5.0. Target dose homogeneity with RSS5.0 was shown comparable to HT2.5 for common clinical sites. Superior normal tissue sparing was observed in RSS5.0 for optic nerves and optic chiasm in brain and HN cases. RSS5.0 demonstrated improved dose sparing for cord and esophagus in lung cases, as well as penile bulb in prostate cases. The mean body dose was comparable for both techniques. For the WBHA cases, the target homogeneity was significantly degraded in RSS2.5 without distinct dose sparing for hippocampus, compared to HT1.0. Conclusions: Compared to the fixed jaw HT delivery, RSS combined with a larger jaw width provides faster treatment delivery and improved cranial-caudal target dose conformity. The target coverage achieved by RSS with a large jaw width is comparable to the fixed jaw HT delivery for common cancer sites, but may deteriorate for cases where complex geometry is present in the middle part of the target.

  17. Direct intratumoral infusion of liposome encapsulated rhenium radionuclides for cancer therapy: Effects of nonuniform intratumoral dose distribution

    SciTech Connect (OSTI)

    Hrycushko, Brian A.; Li Shihong; Goins, Beth; Otto, Randal A.; Bao, Ande [Department of Radiology, University of Texas Health Science Center at San Antonio, San Antonio, Texas 78229 (United States); Department of Otolaryngology-Head and Neck Surgery, University of Texas Health Science Center at San Antonio, San Antonio, Texas 78229 (United States); Department of Radiology, University of Texas Health Science Center at San Antonio, San Antonio, Texas 78229 and Department of Otolaryngology-Head and Neck Surgery, University of Texas Health Science Center at San Antonio, San Antonio, Texas 78229 (United States)

    2011-03-15T23:59:59.000Z

    Purpose: Focused radiation therapy by direct intratumoral infusion of lipid nanoparticle (liposome)-carried beta-emitting radionuclides has shown promising results in animal model studies; however, little is known about the impact the intratumoral liposomal radionuclide distribution may have on tumor control. The primary objective of this work was to investigate the effects the intratumoral absorbed dose distributions from this cancer therapy modality have on tumor control and treatment planning by combining dosimetric and radiobiological modeling with in vivo imaging data. Methods: {sup 99m}Tc-encapsulated liposomes were intratumorally infused with a single injection location to human head and neck squamous cell carcinoma xenografts in nude rats. High resolution in vivo planar imaging was performed at various time points for quantifying intratumoral retention following infusion. The intratumoral liposomal radioactivity distribution was obtained from 1 mm resolution pinhole collimator SPECT imaging coregistered with CT imaging of excised tumors at 20 h postinfusion. Coregistered images were used for intratumoral dosimetric and radiobiological modeling at a voxel level following extrapolation to the therapeutic analogs, {sup 186}Re/{sup 188}Re liposomes. Effective uniform dose (EUD) and tumor control probability (TCP) were used to assess therapy effectiveness and possible methods of improving upon tumor control with this radiation therapy modality. Results: Dosimetric analysis showed that average tumor absorbed doses of 8.6 Gy/MBq (318.2 Gy/mCi) and 5.7 Gy/MBq (209.1 Gy/mCi) could be delivered with this protocol of radiation delivery for {sup 186}Re/{sup 188}Re liposomes, respectively, and 37-92 MBq (1-2.5 mCi)/g tumor administered activity; however, large intratumoral absorbed dose heterogeneity, as seen in dose-volume histograms, resulted in insignificant values of EUD and TCP for achieving tumor control. It is indicated that the use of liposomes encapsulating radionuclides with higher energy beta emissions, dose escalation through increased specific activity, and increasing the number of direct tumor infusion sites improve tumor control. For larger tumors, the use of multiple infusion locations was modeled to be much more efficient, in terms of activity usage, at improving EUD and TCP to achieve a tumoricidal effect. Conclusions: Direct intratumoral infusion of beta-emitting radionuclide encapsulated liposomes shows promise for cancer therapy by achieving large focally delivered tumor doses. However, the results of this work also indicate that average tumor dose may underestimate tumoricidal effect due to substantial heterogeneity in intratumoral liposomal radionuclide distributions. The resulting intratumoral distribution of liposomes following infusion should be taken into account in treatment planning and evaluation in a clinical setting for an optimal cancer therapy.

  18. 3D inpatient dose reconstruction from the PET-CT imaging of {sup 90}Y microspheres for metastatic cancer to the liver: Feasibility study

    SciTech Connect (OSTI)

    Fourkal, E.; Veltchev, I.; Lin, M.; Meyer, J. [Department of Radiation Oncology, Fox Chase Cancer Center, Philadelphia, Pennsylvania 19111 (United States)] [Department of Radiation Oncology, Fox Chase Cancer Center, Philadelphia, Pennsylvania 19111 (United States); Koren, S. [Department of Radiation Oncology, Beth Israel Comprehensive Cancer Center, New York, New York 10011 (United States)] [Department of Radiation Oncology, Beth Israel Comprehensive Cancer Center, New York, New York 10011 (United States); Doss, M.; Yu, J. Q. [Department of Diagnostic Imaging, Fox Chase Cancer Center, Philadelphia, Pennsylvania 19111 (United States)] [Department of Diagnostic Imaging, Fox Chase Cancer Center, Philadelphia, Pennsylvania 19111 (United States)

    2013-08-15T23:59:59.000Z

    Purpose: The introduction of radioembolization with microspheres represents a significant step forward in the treatment of patients with metastatic disease to the liver. This technique uses semiempirical formulae based on body surface area or liver and target volumes to calculate the required total activity for a given patient. However, this treatment modality lacks extremely important information, which is the three-dimensional (3D) dose delivered by microspheres to different organs after their administration. The absence of this information dramatically limits the clinical efficacy of this modality, specifically the predictive power of the treatment. Therefore, the aim of this study is to develop a 3D dose calculation technique that is based on the PET imaging of the infused microspheres.Methods: The Fluka Monte Carlo code was used to calculate the voxel dose kernel for {sup 90}Y source with voxel size equal to that of the PET scan. The measured PET activity distribution was converted to total activity distribution for the subsequent convolution with the voxel dose kernel to obtain the 3D dose distribution. In addition, dose-volume histograms were generated to analyze the dose to the tumor and critical structures.Results: The 3D inpatient dose distribution can be reconstructed from the PET data of a patient scanned after the infusion of microspheres. A total of seven patients have been analyzed so far using the proposed reconstruction method. Four patients underwent treatment with SIR-Spheres for liver metastases from colorectal cancer and three patients were treated with Therasphere for hepatocellular cancer. A total of 14 target tumors were contoured on post-treatment PET-CT scans for dosimetric evaluation. Mean prescription activity was 1.7 GBq (range: 0.58–3.8 GBq). The resulting mean maximum measured dose to targets was 167 Gy (range: 71–311 Gy). Mean minimum dose to 70% of target (D70) was 68 Gy (range: 25–155 Gy). Mean minimum dose to 90% of target (D90) was 53 Gy (range: 13–125 Gy).Conclusions: A three-dimensional inpatient dose reconstruction method has been developed that is based on the PET/CT data of a patient treated with {sup 90}Y microspheres. It allows for a complete description of the absorbed dose by the tumor and critical structures. It represents the first step in building predictive models for treatment outcomes for patients receiving this therapeutic modality as well as it allows for better analysis of patients' dose response and will ultimately improve future treatment administration.

  19. Radiation dose delivered to the proximal penis as a predictor of the risk of erectile dysfunction after three-dimensional conformal radiotherapy for localized prostate cancer

    SciTech Connect (OSTI)

    Wernicke, A. Gabriella [Department of Radiation Oncology, Jefferson Medical College and Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, Pennsylvania (United States); Valicenti, Richard [Department of Radiation Oncology, Jefferson Medical College and Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, Pennsylvania (United States)]. E-mail: richard.valicenti@mail.tju.edu; DiEva, Kelly [Department of Radiation Oncology, Jefferson Medical College and Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, Pennsylvania (United States); Houser, Christopher [Department of Radiation Oncology, Jefferson Medical College and Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, Pennsylvania (United States); Pequignot, Ed [Department of Medicine, Jefferson Medical College and Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA (United States)

    2004-12-01T23:59:59.000Z

    Purpose/objective: In this study, we evaluated in a serial manner whether radiation dose to the bulb of the penis is predictive of erectile dysfunction, ejaculatory difficulty (EJ), and overall satisfaction with sex life (quality of life) by using serial validated self-administered questionnaires. Methods and materials: Twenty-nine potent men with AJCC Stage II prostate cancer treated with three-dimensional conformal radiation therapy alone to a median dose 72.0 Gy (range: 66.6-79.2 Gy) were evaluated by determining the doses received by the penile bulb. The penile bulb was delineated volumetrically, and the dose-volume histogram was obtained on each patient. Results: The median follow-up time was 35 months (range, 16-43 months). We found that for D{sub 30}, D{sub 45}, D{sub 60}, and D{sub 75} (doses to a percent volume of PB: 30%, 45%, 60%, and 75%), higher than the corresponding median dose (defined as high-dose group) correlated with an increased risk of impotence (erectile dysfunction firmness score = 0) (odds ratio [OR] = 7.5, p = 0.02; OR = 7.5, p = 0.02; OR = 8.6, p = 0.008; and OR = 6.9, p = 0.015, respectively). Similarly, for EJD D{sub 30}, D{sub 45}, D{sub 60}, and D{sub 75}, doses higher than the corresponding median ones correlated with worsening ejaculatory function score (EJ = 0 or 1) (OR = 8, p = 0.013; OR = 8, p 0.013; OR = 9.2, p = 0.015; and OR = 8, p = 0.026, respectively). For quality of life, low ({<=}median dose) dose groups of patients improve over time, whereas high-dose groups of patients worsen. Conclusions: This study supports the existence of a penile bulb dose-volume relationship underlying the development of radiation-induced erectile dysfunction. Our data may guide the use of inverse treatment planning to maximize the probability of maintaining sexual potency after radiation therapy.

  20. Intensity-modulated radiotherapy improves lymph node coverage and dose to critical structures compared with three-dimensional conformal radiation therapy in clinically localized prostate cancer

    SciTech Connect (OSTI)

    Wang-Chesebro, Alice [Radiation Oncology, University of California-San Francisco, San Francisco, CA (United States)]. E-mail: awang@radonc17.ucsf.edu; Xia Ping [Radiation Oncology, University of California-San Francisco, San Francisco, CA (United States); Coleman, Joy [Radiation Oncology, University of California-San Francisco, San Francisco, CA (United States); Akazawa, Clayton C. [Radiation Oncology, University of California-San Francisco, San Francisco, CA (United States); Roach, Mack [Radiation Oncology, University of California-San Francisco, San Francisco, CA (United States)

    2006-11-01T23:59:59.000Z

    Purpose: The aim of this study was to quantify gains in lymph node coverage and critical structure dose reduction for whole-pelvis (WP) and extended-field (EF) radiotherapy in prostate cancer using intensity-modulated radiotherapy (IMRT) compared with three-dimensional conformal radiotherapy (3DCRT) for the first treatment phase of 45 Gy in the concurrent treatment of lymph nodes and prostate. Methods and Materials: From January to August 2005, 35 patients with localized prostate cancer were treated with pelvic IMRT; 7 had nodes defined up to L5-S1 (Group 1), and 28 had nodes defined above L5-S1 (Group 2). Each patient had 2 plans retrospectively generated: 1 WP 3DCRT plan using bony landmarks, and 1 EF 3DCRT plan to cover the vascular defined volumes. Dose-volume histograms for the lymph nodes, rectum, bladder, small bowel, and penile bulb were compared by group. Results: For Group 1, WP 3DCRT missed 25% of pelvic nodes with the prescribed dose 45 Gy and missed 18% with the 95% prescribed dose 42.75 Gy, whereas WP IMRT achieved V{sub 45Gy} = 98% and V{sub 42.75Gy} = 100%. Compared with WP 3DCRT, IMRT reduced bladder V{sub 45Gy} by 78%, rectum V{sub 45Gy} by 48%, and small bowel V{sub 45Gy} by 232 cm{sup 3}. EF 3DCRT achieved 95% coverage of nodes for all patients at high cost to critical structures. For Group 2, IMRT decreased bladder V{sub 45Gy} by 90%, rectum V{sub 45Gy} by 54% and small bowel V{sub 45Gy} by 455 cm{sup 3} compared with EF 3DCRT. Conclusion: In this study WP 3DCRT missed a significant percentage of pelvic nodes. Although EF 3DCRT achieved 95% pelvic nodal coverage, it increased critical structure doses. IMRT improved pelvic nodal coverage while decreasing dose to bladder, rectum, small bowel, and penile bulb. For patients with extended node involvement, IMRT especially decreases small bowel dose.

  1. A study of IMRT planning parameters on planning efficiency, delivery efficiency, and plan quality

    SciTech Connect (OSTI)

    Mittauer, Kathryn [Department of Radiation Oncology, College of Medicine, University of Florida, Gainesville, Florida 32603 and J. Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, Gainesville, Florida 32611 (United States); Lu Bo; Yan Guanghua; Kahler, Darren; Amdur, Robert; Liu Chihray [Department of Radiation Oncology, College of Medicine, University of Florida, Gainesville, Florida 32603 (United States); Gopal, Arun [Department of Radiation Oncology, New York-Presbyterian Hospital, Columbia University, New York, New York 10032 (United States)

    2013-06-15T23:59:59.000Z

    Purpose: To improve planning and delivery efficiency of head and neck IMRT without compromising planning quality through the evaluation of inverse planning parameters.Methods: Eleven head and neck patients with pre-existing IMRT treatment plans were selected for this retrospective study. The Pinnacle treatment planning system (TPS) was used to compute new treatment plans for each patient by varying the individual or the combined parameters of dose/fluence grid resolution, minimum MU per segment, and minimum segment area. Forty-five plans per patient were generated with the following variations: 4 dose/fluence grid resolution plans, 12 minimum segment area plans, 9 minimum MU plans, and 20 combined minimum segment area/minimum MU plans. Each plan was evaluated and compared to others based on dose volume histograms (DVHs) (i.e., plan quality), planning time, and delivery time. To evaluate delivery efficiency, a model was developed that estimated the delivery time of a treatment plan, and validated through measurements on an Elekta Synergy linear accelerator. Results: The uncertainty (i.e., variation) of the dose-volume index due to dose calculation grid variation was as high as 8.2% (5.5 Gy in absolute dose) for planning target volumes (PTVs) and 13.3% (2.1 Gy in absolute dose) for planning at risk volumes (PRVs). Comparison results of dose distributions indicated that smaller volumes were more susceptible to uncertainties. The grid resolution of a 4 mm dose grid with a 2 mm fluence grid was recommended, since it can reduce the final dose calculation time by 63% compared to the accepted standard (2 mm dose grid with a 2 mm fluence grid resolution) while maintaining a similar level of dose-volume index variation. Threshold values that maintained adequate plan quality (DVH results of the PTVs and PRVs remained satisfied for their dose objectives) were 5 cm{sup 2} for minimum segment area and 5 MU for minimum MU. As the minimum MU parameter was increased, the number of segments and delivery time were decreased. Increasing the minimum segment area parameter decreased the plan MU, but had less of an effect on the number of segments and delivery time. Our delivery time model predicted delivery time to within 1.8%. Conclusions: Increasing the dose grid while maintaining a small fluence grid allows for improved planning efficiency without compromising plan quality. Delivery efficiency can be improved by increasing the minimum MU, but not the minimum segment area. However, increasing the respective minimum MU and/or the minimum segment area to any value greater than 5 MU and 5 cm{sup 2} is not recommended because it degrades plan quality.

  2. A feasibility study of reactor-based deep-burn concepts.

    SciTech Connect (OSTI)

    Kim, T. K.; Taiwo, T. A.; Hill, R. N.; Yang, W. S.

    2005-09-16T23:59:59.000Z

    A systematic assessment of the General Atomics (GA) proposed Deep-Burn concept based on the Modular Helium-Cooled Reactor design (DB-MHR) has been performed. Preliminary benchmarking of deterministic physics codes was done by comparing code results to those from MONTEBURNS (MCNP-ORIGEN) calculations. Detailed fuel cycle analyses were performed in order to provide an independent evaluation of the physics and transmutation performance of the one-pass and two-pass concepts. Key performance parameters such as transuranic consumption, reactor performance, and spent fuel characteristics were analyzed. This effort has been undertaken in close collaborations with the General Atomics design team and Brookhaven National Laboratory evaluation team. The study was performed primarily for a 600 MWt reference DB-MHR design having a power density of 4.7 MW/m{sup 3}. Based on parametric and sensitivity study, it was determined that the maximum burnup (TRU consumption) can be obtained using optimum values of 200 {micro}m and 20% for the fuel kernel diameter and fuel packing fraction, respectively. These values were retained for most of the one-pass and two-pass design calculations; variation to the packing fraction was necessary for the second stage of the two-pass concept. Using a four-batch fuel management scheme for the one-pass DB-MHR core, it was possible to obtain a TRU consumption of 58% and a cycle length of 286 EFPD. By increasing the core power to 800 MWt and the power density to 6.2 MW/m{sup 3}, it was possible to increase the TRU consumption to 60%, although the cycle length decreased by {approx}64 days. The higher TRU consumption (burnup) is due to the reduction of the in-core decay of fissile Pu-241 to Am-241 relative to fission, arising from the higher power density (specific power), which made the fuel more reactivity over time. It was also found that the TRU consumption can be improved by utilizing axial fuel shuffling or by operating with lower material temperatures (colder core). Results also showed that the transmutation performance of the one-pass deep-burn concept is sensitive to the initial TRU vector, primarily because longer cooling time reduces the fissile content (Pu-241 specifically.) With a cooling time of 5 years, the TRU consumption increases to 67%, while conversely, with 20-year cooling the TRU consumption is about 58%. For the two-pass DB-MHR (TRU recycling option), a fuel packing fraction of about 30% is required in the second pass (the recycled TRU). It was found that using a heterogeneous core (homogeneous fuel element) concept, the TRU consumption is dependent on the cooling interval before the 2nd pass, again due to Pu-241 decay during the time lag between the first pass fuel discharge and the second pass fuel charge. With a cooling interval of 7 years (5 and 2 years before and after reprocessing) a TRU consumption of 55% is obtained. With an assumed ''no cooling'' interval, the TRU consumption is 63%. By using a cylindrical core to reduce neutron leakage, TRU consumption of the case with 7-year cooling interval increases to 58%. For a two-pass concept using a heterogeneous fuel element (and homogeneous core) with first and second pass volume ratio of 2:1, the TRU consumption is 62.4%. Finally, the repository loading benefits arising from the deep-burn and Inert Matrix Fuel (IMF) concepts were estimated and compared, for the same initial TRU vector. The DB-MHR concept resulted in slightly higher TRU consumption and repository loading benefit compared to the IMF concept (58.1% versus 55.1% for TRU consumption and 2.0 versus 1.6 for estimated repository loading benefit).

  3. CO2 Sequestration Potential of Texas Low-Rank Coals

    SciTech Connect (OSTI)

    Duane A. McVay; Walter B. Ayers Jr; Jerry L. Jensen

    2005-10-01T23:59:59.000Z

    The objectives of this project are to evaluate the feasibility of carbon dioxide (CO{sub 2}) sequestration in Texas low-rank coals and to determine the potential for enhanced coalbed methane (ECBM) recovery as an added benefit of sequestration. The main objectives for this reporting period were to perform reservoir simulation and economic sensitivity studies to (1) determine the effects of injection gas composition, (2) determine the effects of injection rate, and (3) determine the effects of coal dewatering prior to CO{sub 2} injection on CO{sub 2} sequestration in the Lower Calvert Bluff Formation (LCB) of the Wilcox Group coals in east-central Texas. To predict CO{sub 2} sequestration and ECBM in LCB coal beds for these three sensitivity studies, we constructed a 5-spot pattern reservoir simulation model and selected reservoir parameters representative of a typical depth, approximately 6,200-ft, of potential LCB coalbed reservoirs in the focus area of East-Central Texas. Simulation results of flue gas injection (13% CO{sub 2} - 87% N{sub 2}) in an 80-acre 5-spot pattern (40-ac well spacing) indicate that LCB coals with average net thickness of 20 ft can store a median value of 0.46 Bcf of CO{sub 2} at depths of 6,200 ft, with a median ECBM recovery of 0.94 Bcf and median CO{sub 2} breakthrough time of 4,270 days (11.7 years). Simulation of 100% CO{sub 2} injection in an 80-acre 5-spot pattern indicated that these same coals with average net thickness of 20 ft can store a median value of 1.75 Bcf of CO{sub 2} at depths of 6,200 ft with a median ECBM recovery of 0.67 Bcf and median CO{sub 2} breakthrough time of 1,650 days (4.5 years). Breakthrough was defined as the point when CO{sub 2} comprised 5% of the production stream for all cases. The injection rate sensitivity study for pure CO{sub 2} injection in an 80-acre 5-spot pattern at 6,200-ft depth shows that total volumes of CO{sub 2} sequestered and methane produced do not have significant sensitivity to injection rate. The main difference is in timing, with longer breakthrough times resulting as injection rate decreases. Breakthrough times for 80-acre patterns (40-acre well spacing) ranged from 670 days (1.8 years) to 7,240 days (19.8 years) for the reservoir parameters and well operating conditions investigated. The dewatering sensitivity study for pure CO{sub 2} injection in an 80-acre 5-spot pattern at 6,200-ft depth shows that total volumes of CO{sub 2} sequestered and methane produced do not have significant sensitivity to dewatering prior to CO{sub 2} injection. As time to start CO{sub 2} injection increases, the time to reach breakthrough also increases. Breakthrough times for 80-acre patterns (40-acre well spacing) ranged from 850 days (2.3 years) to 5,380 days (14.7 years) for the reservoir parameters and well injection/production schedules investigated. Preliminary economic modeling results using a gas price of $7-$8 per Mscf and CO{sub 2} credits of $1.33 per ton CO{sub 2} indicate that injection of flue gas (87% N{sub 2}-13% CO{sub 2}) and 50% N{sub 2}-50% CO{sub 2} are more economically viable than injecting 100% CO{sub 2}. Results also indicate that injection rate and duration and timing of dewatering prior to CO{sub 2} injection have no significant effect on the economic viability of the project(s).

  4. Long-Term Outcomes From a Prospective Trial of Stereotactic Body Radiotherapy for Low-Risk Prostate Cancer

    SciTech Connect (OSTI)

    King, Christopher R., E-mail: crking@mednet.ucla.edu [Departments of Radiation Oncology and Urology, University of California Los Angeles School of Medicine, Los Angeles, CA (United States); Brooks, James D.; Gill, Harcharan; Presti, Joseph C. [Department of Urology, Stanford University School of Medicine, Stanford, CA (United States)

    2012-02-01T23:59:59.000Z

    Purpose: Hypofractionated radiotherapy has an intrinsically different normal tissue and tumor radiobiology. The results of a prospective trial of stereotactic body radiotherapy (SBRT) for prostate cancer with long-term patient-reported toxicity and tumor control rates are presented. Methods and Materials: From 2003 through 2009, 67 patients with clinically localized low-risk prostate cancer were enrolled. Treatment consisted of 36.25 Gy in 5 fractions using SBRT with the CyberKnife as the delivery technology. No patient received hormone therapy. Patient self-reported bladder and rectal toxicities were graded on the Radiation Therapy Oncology Group scale (RTOG). Results: Median follow-up was 2.7 years. There were no grade 4 toxicities. Radiation Therapy Oncology Group Grade 3, 2, and 1 bladder toxicities were seen in 3% (2 patients), 5% (3 patients), and 23% (13 patients) respectively. Dysuria exacerbated by urologic instrumentation accounted for both patients with Grade 3 toxicity. Urinary incontinence, complete obstruction, or persistent hematuria was not observed. Rectal Grade 3, 2, and 1 toxicities were seen in 0, 2% (1 patient), and 12.5% (7 patients), respectively. Persistent rectal bleeding was not observed. Low-grade toxicities were substantially less frequent with QOD vs. QD dose regimen (p = 0.001 for gastrointestinal and p = 0.007 for genitourinary). There were two prostate-specific antigen (PSA), biopsy-proven failures with negative metastatic workup. Median PSA at follow-up was 0.5 {+-} 0.72 ng/mL. The 4-year Kaplan-Meier PSA relapse-free survival was 94% (95% confidence interval, 85%-102%). Conclusion: Significant late bladder and rectal toxicities from SBRT for prostate cancer are infrequent. PSA relapse-free survival compares favorably with other definitive treatments. The current evidence supports consideration of stereotactic body radiotherapy among the therapeutic options for localized prostate cancer.

  5. Revised analyses of decommissioning for the reference boiling water reactor power station. Effects of current regulatory and other considerations on the financial assurance requirements of the decommissioning rule and on estimates of occupational radiation exposure: Appendices, draft report for comment. Volume 2

    SciTech Connect (OSTI)

    Smith, R.I.; Bierschbach, M.C.; Konzek, G.J. [Pacific Northwest Lab., Richland, WA (United States)] [and others

    1994-09-01T23:59:59.000Z

    On June 27, 1988, the U.S. Nuclear Regulatory Commission (NRC) published in the Federal Register (53 FR 24018) the final rule for the General Requirements for Decommissioning Nuclear Facilities. With the issuance of the final rule, owners and operators of licensed nuclear power plants are required to prepare, and submit to the NRC for review, decommissioning plans and cost estimates. The NRC staff is in need of updated bases documentation that will assist them in assessing the adequacy of the licensee submittals, from the viewpoint of both the planned actions, including occupational radiation exposure, and the probable costs. The purpose of this reevaluation study is to update the needed bases documentation. This report presents the results of a review and reevaluation of the PNL 1980 decommissioning study of the Washington Public Power Supply System`s WNP-2, including all identifiable factors and cost assumptions which contribute significantly to the total cost of decommissioning the plant for the DECON, SAFSTOR, and ENTOMB decommissioning alternatives, which now include an initial 5-7 year period during which time the spent fuel is stored in the spent fuel pool prior to beginning major disassembly or extended safe storage of the plant. This report also includes consideration of the NRC requirement that decontamination and decommissioning activities leading to termination of the nuclear license be completed within 60 years of final reactor shutdown, consideration of packaging and disposal requirements for materials whose radionuclide concentrations exceed the limits for Class C low-level waste. Costs for labor, materials, transport, and disposal activities are given in 1993 dollars. Sensitivities of the total license termination cost to the disposal costs at different low-level radioactive waste disposal sites, to different depths of contaminated concrete surface removal within the facilities, and to different transport distances are also examined.

  6. Revised analyses of decommissioning for the reference boiling water reactor power station. Effects of current regulatory and other considerations on the financial assurance requirements of the decommissioning rule and on estimates of occupational radiation exposure - appendices. Final report

    SciTech Connect (OSTI)

    Smith, R.I.; Bierschbach, M.C.; Konzek, G.J.; McDuffie, P.N.

    1996-07-01T23:59:59.000Z

    The NRC staff is in need of decommissioning bases documentation that will assist them in assessing the adequacy of the licensee submittals, from the viewpoint of both the planned actions, including occupational radiation exposure, and the probable costs. The purpose of this reevaluation study is to update the needed bases documentation. This report presents the results of a review and reevaluation of the PNL 1980 decommissioning study of the Washington Public Power Supply System`s Washington Nuclear Plant Two (WNP-2) located at Richland, Washington, including all identifiable factors and cost assumptions which contribute significantly to the total cost of decommissioning the plant for the DECON, SAFSTOR, and ENTOMB decommissioning alternatives. These alternatives now include an initial 5-7 year period during which time the spent fuel is stored in the spent fuel pool prior to beginning major disassembly or extended safe storage of the plant. Included for information (but not presently part of the license termination cost) is an estimate of the cost to demolish the decontaminated and clear structures on the site and to restore the site to a {open_quotes}green field{close_quotes} condition. This report also includes consideration of the NRC requirement that decontamination and decommissioning activities leading to termination of the nuclear license be completed within 60 years of final reactor shutdown, consideration of packaging and disposal requirements for materials whose radionuclide concentrations exceed the limits for Class C low-level waste (i.e., Greater-Than-Class C), and reflects 1993 costs for labor, materials, transport, and disposal activities. Sensitivity of the total license termination cost to the disposal costs at different low-level radioactive waste disposal sites, to different depths of contaminated concrete surface removal within the facilities, and to different transport distances is also examined.

  7. Revised analyses of decommissioning for the reference pressurized Water Reactor Power Station. Volume 2, Effects of current regulatory and other considerations on the financial assurance requirements of the decommissioning rule and on estimates of occupational radiation exposure: Appendices, Final report

    SciTech Connect (OSTI)

    Konzek, G.J.; Smith, R.I.; Bierschbach, M.C.; McDuffie, P.N.

    1995-11-01T23:59:59.000Z

    With the issuance of the final Decommissioning Rule (July 27, 1998), owners and operators of licensed nuclear power plants are required to prepare, and submit to the US Nuclear Regulatory Commission (NRC) for review, decommissioning plans and cost estimates. The NRC staff is in need of bases documentation that will assist them in assessing the adequacy of the licensee submittals, from the viewpoint of both the planned actions, including occupational radiation exposure, and the probable costs. The purpose of this reevaluation study is to provide some of the needed bases documentation. This report contains the results of a review and reevaluation of the 1978 PNL decommissioning study of the Trojan nuclear power plant (NUREG/CR-0130), including all identifiable factors and cost assumptions which contribute significantly to the total cost of decommissioning the nuclear power plant for the DECON, SAFSTOR, and ENTOMB decommissioning alternatives. These alternatives now include an initial 5--7 year period during which time the spent fuel is stored in the spent fuel pool, prior to beginning major disassembly or extended safe storage of the plant. Included for information (but not presently part of the license termination cost) is an estimate of the cost to demolish the decontaminated and clean structures on the site and to restore the site to a ``green field`` condition. This report also includes consideration of the NRC requirement that decontamination and decommissioning activities leading to termination of the nuclear license be completed within 60 years of final reactor shutdown, consideration of packaging and disposal requirements for materials whose radionuclide concentrations exceed the limits for Class C low-level waste (i.e., Greater-Than-Class C), and reflects 1993 costs for labor, materials, transport, and disposal activities.

  8. Performance Evaluation of HYCOM-GOM for Hydrokinetic Resource Assessment in the Florida Strait

    SciTech Connect (OSTI)

    Neary, Vincent S [ORNL; Gunawan, Budi [ORNL; Ryou, Albert S [ORNL

    2012-06-01T23:59:59.000Z

    The U.S. Department of Energy (DoE) is assessing and mapping the potential off-shore ocean current hydrokinetic energy resources along the U.S. coastline, excluding tidal currents, to facilitate market penetration of water power technologies. This resource assessment includes information on the temporal and three-dimensional spatial distribution of the daily averaged power density, and the overall theoretical hydrokinetic energy production, based on modeled historical simulations spanning a 7-year period of record using HYCOM-GOM, an ocean current observation assimilation model that generates a spatially distributed three-dimensional representation of daily averaged horizontal current magnitude and direction time series from which power density time series and their statistics can be derived. This study ascertains the deviation of HYCOM-GOM outputs, including transport (flow) and power density, from outputs based on three independent observation sources to evaluate HYCOM-GOM performance. The three independent data sources include NOAA s submarine cable data of transport, ADCP data at a high power density location, and HF radar data in the high power density region of the Florida Strait. Comparisons with these three independent observation sets indicate discrepancies with HYCOM model outputs, but overall indicate that the HYCOM-GOM model can provide an adequate assessment of the ocean current hydrokinetic resource in high power density regions like the Florida Strait. Additional independent observational data, in particular stationary ADCP measurements, would be useful for expanding this model performance evaluation study. ADCP measurements are rare in ocean environments not influenced by tides, and limited to one location in the Florida Strait. HF radar data, although providing great spatial coverage, is limited to surface currents only.

  9. CMB constraint on non-Gaussianity in isocurvature perturbations

    SciTech Connect (OSTI)

    Hikage, Chiaki [Kobayashi-Maskawa Institute, Nagoya University, Nagoya 464-8602 (Japan); Kawasaki, Masahiro [Institute for Cosmic Ray Research, University of Tokyo, Kashiwa 277-8582 (Japan); Sekiguchi, Toyokazu [Department of Physics and Astrophysics, Nagoya University, Nagoya 464-8602 (Japan); Takahashi, Tomo, E-mail: hikage@kmi.nagoya-u.ac.jp, E-mail: kawasaki@icrr.u-tokyo.ac.jp, E-mail: toyokazu.sekiguchi@nagoya-u.jp, E-mail: tomot@cc.saga-u.ac.jp [Department of Physics, Saga University, Saga 840-8502 (Japan)

    2013-07-01T23:59:59.000Z

    We study the CMB constraints on non-Gaussianity in CDM isocurvature perturbations. Non-Gaussian isocurvature perturbations can be produced in various models at the very early stage of the Universe. Since the isocurvature perturbations little affect the structure formation at late times, CMB is the best probe of isocurvature non-Gaussianity at least in the near future. In this paper, we focus on non-Gaussian curvature and isocurvature perturbations of the local-type, which are uncorrelated and in the form ? = ?{sub G}+(3/5)f{sub NL}(?{sub G}{sup 2}?(?{sub G}{sup 2})) and S = S{sub G}+f{sub NL}{sup (ISO)}(S{sub G}?(S{sub G}{sup 2})), and constrain the non-linearity parameter of isocurvature perturbations, f{sub NL}{sup (ISO)}, as well as the curvature one f{sub NL}. For this purpose, we employ several state-of-art techniques for the analysis of CMB data and simulation. Assuming that isocurvature perturbations are subdominant, we apply our method to the WMAP 7-year data of temperature anisotropy and obtain constraints on a combination ?{sup 2}f{sub NL}{sup (ISO)}, where ? is the ratio of the power spectrum of isocurvature perturbations to that of the adiabatic ones. When the adiabatic perturbations are assumed to be Gaussian, we obtained a constraint ?{sup 2}f{sub NL}{sup (ISO)} = 40±66 assuming the power spectrum of isocurvature perturbations is scale-invariant. When we assume that the adiabatic perturbations can also be non-Gaussian, we obtain f{sub NL} = 38±24 and ?{sup 2}f{sub NL}{sup (ISO)} = ?8±72. We also discuss implications of our results for the axion CDM isocurvature model.

  10. A SEARCH FOR HIGH PROPER MOTION T DWARFS WITH Pan-STARRS1 + 2MASS + WISE

    SciTech Connect (OSTI)

    Liu, Michael C.; Deacon, Niall R.; Magnier, Eugene A.; Aller, Kimberly M.; Bowler, Brendan P.; Burgett, W. S.; Chambers, K. C.; Hodapp, K. W.; Kaiser, N.; Kudritzki, R.-P.; Morgan, J. S.; Tonry, J. L.; Wainscoat, R. J. [Institute for Astronomy, University of Hawaii, Honolulu, HI 96822 (United States); Dupuy, Trent J. [Harvard-Smithsonian Center for Astrophysics, Cambridge, MA 02138 (United States); Redstone, Joshua [Facebook, Palo Alto, CA 94304 (United States); Goldman, Bertrand [Max Planck Institute for Astronomy, D-69117 Heidelberg (Germany); Price, P. A. [Department of Astrophysical Sciences, Princeton University, Princeton, NJ 08544 (United States)

    2011-10-20T23:59:59.000Z

    We have searched {approx}8200 deg{sup 2} for high proper motion ({approx}0.''5-2.''7 year{sup -1}) T dwarfs by combining first-epoch data from the Pan-STARRS1 (PS1) 3{pi} Survey, the Two Micron All Sky Survey (2MASS) All-Sky Point Source Catalog, and the WISE Preliminary Data Release. We identified two high proper motion objects with the very red (W1 - W2) colors characteristic of T dwarfs, one being the known T7.5 dwarf GJ 570D. Near-IR spectroscopy of the other object (PSO J043.5395+02.3995 {identical_to} WISEP J025409.45+022359.1) reveals a spectral type of T8, leading to a photometric distance of 7.2 {+-} 0.7 pc. The 2.''56 year{sup -1} proper motion of PSO J043.5+02 is the second highest among field T dwarfs, corresponding to a tangential velocity of 87 {+-} 8 km s{sup -1}. According to the Besancon galaxy model, this velocity indicates that its galactic membership is probably in the thin disk, with the thick disk an unlikely possibility. Such membership is in accord with the near-IR spectrum, which points to a surface gravity (age) and metallicity typical of the field population. We combine 2MASS, Sloan Digital Sky Survey, WISE, and PS1 astrometry to derive a preliminary parallax of 171 {+-} 45 mas (5.8{sup +2.0} {sub -1.2} pc), the first such measurement using PS1 data. The proximity and brightness of PSO J043.5+02 will facilitate future characterization of its atmosphere, variability, multiplicity, distance, and kinematics. The modest number of candidates from our search suggests that the immediate ({approx}10 pc) solar neighborhood does not contain a large reservoir of undiscovered T dwarfs earlier than about T8.

  11. Final Technical Report: Response of Mediterranean-Type Ecosystems to Elevated Atmospheric CO2 and Associated Climate Change

    SciTech Connect (OSTI)

    Oechel, Walter C

    2002-08-15T23:59:59.000Z

    This research incorporated an integrated hierarchical approach in space, time, and levels of biological/ecological organization to help understand and predict ecosystem response to elevated CO{sub 2} and concomitant environmental change. The research utilized a number of different approaches, and collaboration of both PER and non-PER investigators to arrive at a comprehensive, integrative understanding. Central to the work were the CO{sub 2}-controlled, ambient Lit, Temperature controlled (CO{sub 2}LT) null-balance chambers originally developed in the arctic tundra, which were re-engineered for the chaparral with treatment CO{sub 2} concentrations of from 250 to 750 ppm CO{sub 2} in 100 ppm increments, replicated twice to allow for a regression analysis. Each chamber was 2 meters on a side and 2 meters tall, which were installed over an individual shrub reprouting after a fire. This manipulation allowed study of the response of native chaparral to varying levels of CO{sub 2}, while regenerating from an experimental burn. Results from these highly-controlled manipulations were compared against Free Air CO{sub 2} Enrichment (FACE) manipulations, in an area adjacent to the CO{sub 2}LT null balance greenhouses. These relatively short-term results (5-7 years) were compared to long-term results from Mediterranean-type ecosystems (MTEs) surrounding natural CO{sub 2} springs in northern Italy, near Laiatico, Italy. The springs lack the controlled experimental rigor of our CO{sub 2}LT and FACE manipulation, but provide invaluable validation of our long-term predictions.

  12. Unification of Dynamical Determination and Bare Minimal Phenomenological Constraints in No-Scale F-SU(5)

    E-Print Network [OSTI]

    Tianjun Li; James A. Maxin; Dimitri V. Nanopoulos; Joel W. Walker

    2012-03-19T23:59:59.000Z

    We revisit the construction of the viable parameter space of No-Scale F-SU(5), a model built on the F-lipped SU(5)xU(1)_X gauge group, supplemented by a pair of F-theory derived vector-like multiplets at the TeV scale, and the dynamically established boundary conditions of No-Scale Supergravity. Employing an updated numerical algorithm and a substantially upgraded computational engine, we significantly enhance the scope, detail and accuracy of our prior study. We sequentially apply a set of "bare-minimal" phenomenological constraints, consisting of i) the dynamically established boundary conditions of No-Scale Supergravity, ii) consistent radiative electroweak symmetry breaking, iii) precision LEP constraints on the light supersymmetric mass content, iv) the world average top-quark mass, and v) a light neutralino satisfying the 7-year WMAP cold dark matter relic density measurement. The overlap of the viable parameter space with key rare-process limits on the branching ratio for b to s gamma and the muon anomalous magnetic moment is identified as the "golden strip" of F-SU(5). A cross check for top-down theoretical consistency is provided by application of the "Super No-Scale" condition, which dynamically selects a pair of undetermined model parameters in a manner that is virtually identical to the corresponding phenomenological (driven primarily by the relic density) selection. The predicted vector-like particles are candidates for production at the future LHC, which is furthermore sensitive to a distinctive signal of ultra-high multiplicity hadronic jets. The lightest CP-even Higgs boson mass is predicted to be 120+3.5-1 GeV, with an additional 3-4 GeV upward shift possible from radiative loops in the vector-like multiplets. The predominantly bino flavored lightest neutralino is suitable for direct detection by the Xenon collaboration.

  13. The influence of cosmic rays on the size of the Antarctic Ozone Hole

    E-Print Network [OSTI]

    M. Alvarez Madrigal; J. Perez Peraza; V. M. Velasco

    2010-01-15T23:59:59.000Z

    The Antarctic region in which severe ozone depletion has taken place is known as the ozone hole. This region has two basic indicators: the area, where the ozone abundance is low (size), and the quantity of ozone mass deficit (depth). The energetic particles that penetrate deeply into the atmosphere and galactic cosmic rays (GCR) modify the ozone abundance in the stratosphere. With this research project, we are looking for evidence of a connection between variations in the cosmic ray flux and variations in the size of the ozone hole. In addition, we are looking for signs of the kind of processes that physically connect GCR fluxes with variations in the stratospheric ozone hole size (OHS) in the Antarctic region. With this goal in mind, we also analyze here the atmospheric temperature (AT) anomalies, which have often been linked with such variations. Using Morlet's wavelet spectral analysis to compute the coherence between two time series, we found that during the analyzed period (1982-2005), there existed a common signal of around 3 and 5 years between the OHS and GCR time series, during September and November, respectively. In both cases, the relationship showed a time-dependent anti-correlation between the two series. On the other hand, for October the analysis showed a time-dependent correlation that occurs around 1.7 years. These results seem to indicate that there exist at least two kinds of modulation processes of GCR fluxes on the OHS that work simultaneously but that change their relative relevance along the timeline.

  14. Cooling curves and initial models for low-mass white dwarfs (<0.25 Msun) with helium core

    E-Print Network [OSTI]

    Marek J. Sarna; Ene Ergma; Jelena Antipova

    2000-02-11T23:59:59.000Z

    We present a detailed calculation of the evolution of low-mass ($< 0.25~M_\\odot $) helium white dwarfs. These white dwarfs (the optical companions to binary millisecond pulsars) are formed via long-term, low-mass binary evolution. After detachment from the Roche lobe, the hot helium cores have a rather thick hydrogen layer with mass between 0.01 to 0.06$~M_\\odot $. Due to mixing between the core and outer envelope, the surface hydrogen content is 0.5 to 0.35, depending on the initial value of the heavy element (Z) and the initial secondary mass. We found that the majority of our computed models experience one or two hydrogen shell flashes. We found that the mass of the helium dwarf in which the hydrogen shell flash occurs depends on the chemical composition. The minimum helium white dwarf mass in which a hydrogen flash takes place is 0.213$~M_\\odot $ (Z=0.003), 0.198$~M_\\odot $ (Z=0.01), 0.192$~M_\\odot $ (Z=0.02) or 0.183$~M_\\odot $ (Z=0.03). The duration of the flashes (independent of chemical composition) is between few $\\times 10^6 $ years to few $\\times 10^7 $ years. In several flashes the white dwarf radius will increase so much that it forces the model to fill its Roche lobe again. Our calculations show that cooling history of the helium white dwarf depends dramatically on the thickness of the hydrogen layer. We show that the transition from a cooling white dwarf with a temporary stable hydrogen-burning shell to a cooling white dwarf in which almost all residual hydrogen is lost in a few thermal flashes (via Roche-lobe overflow) occurs between 0.183-0.213$~M_\\odot $ (depending on the heavy element value).

  15. Reconciling estimates of the contemporary North American carbon balance among terrestrial biosphere models, atmospheric inversions and a new approach for estimating net ecosystem exchange from inventory-based data

    SciTech Connect (OSTI)

    Hayes, Daniel J [ORNL; Turner, David P [Oregon State University, Corvallis; Stinson, Graham [Pacific Forestry Centre, Canadian Forest Service; Mcguire, David [University of Alaska; Wei, Yaxing [ORNL; West, Tristram O. [Joint Global Change Research Institute, PNNL; Heath, Linda S. [USDA Forest Service; De Jong, Bernardus [ECOSUR; McConkey, Brian G. [Agriculture and Agri-Food Canada; Birdsey, Richard A. [U.S. Department of Agriculture Forest Service; Kurz, Werner [Canadian Forest Service; Jacobson, Andrew [NOAA ESRL and CIRES; Huntzinger, Deborah [University of Michigan; Pan, Yude [U.S. Department of Agriculture Forest Service; Post, Wilfred M [ORNL; Cook, Robert B [ORNL

    2012-01-01T23:59:59.000Z

    We develop an approach for estimating net ecosystem exchange (NEE) using inventory-based information over North America (NA) for a recent 7-year period (ca. 2000 2006). The approach notably retains information on the spatial distribution of NEE, or the vertical exchange between land and atmosphere of all non-fossil fuel sources and sinks of CO2, while accounting for lateral transfers of forest and crop products as well as their eventual emissions. The total NEE estimate of a 327 252 TgC yr1 sink for NA was driven primarily by CO2 uptake in the Forest Lands sector (248 TgC yr1), largely in the Northwest and Southeast regions of the US, and in the Crop Lands sector (297 TgC yr1), predominantly in the Midwest US states. These sinks are counteracted by the carbon source estimated for the Other Lands sector (+218 TgC yr1), where much of the forest and crop products are assumed to be returned to the atmosphere (through livestock and human consumption). The ecosystems of Mexico are estimated tobe a small net source (+18 TgC yr1) due to land use change between 1993 and 2002. We compare these inventorybased estimates with results from a suite of terrestrial biosphere and atmospheric inversion models, where the mean continental-scale NEE estimate for each ensemble is 511 TgC yr1 and 931 TgC yr1, respectively. In the modeling approaches, all sectors, including Other Lands, were generally estimated to be a carbon sink, driven in part by assumed CO2 fertilization and/or lack of consideration of carbon sources from disturbances and product emissions. Additional fluxes not measured by the inventories, although highly uncertain, could add an additional 239 TgC yr1 to the inventory-based NA sink estimate, thus suggesting some convergence with the modeling approaches.

  16. Physical Properties of Very Powerful FRII Radio Galaxies

    E-Print Network [OSTI]

    Christopher P. O'Dea; Ruth A. Daly; Preeti Kharb; Kenneth A. Freeman; Stefi A. Baum

    2008-10-07T23:59:59.000Z

    We estimate ages and physical properties of powerful radio galaxies. An analysis of new multi-wavelength VLA observations of eleven very powerful classical double (FRIIb) radio galaxies with redshifts between 0.4 and 1.3 is presented. We estimate ages and velocities for each side of each source. The eleven new sources are combined with previously studied samples and the characteristics of the full sample of 31 sources are studied; the full sample includes sources with redshifts between 0.056 and 1.79, and core-hot spot sizes of about 30 to 400 kpc. The velocities are independent of core-hotspot separation, suggesting the rate of growth of a given source is roughly constant over the source lifetime. We combine the rate of growth, width, and pressure of a source to study the beam power, lifetime, energy, and ambient gas density using standard methods previously applied to smaller samples. Typical beam powers are in the range from 1E44 to 1E46 erg/s; we show that this quantity is insensitive to assumptions regarding minimum energy conditions. The beam powers are independent of core-hotspot separation suggesting that the beam power of a given source is roughly constant over the source lifetime. Typical total source lifetimes are found to be about a few E6 to E7 years, and typical total outflow energies (E/c^2) are found to be about 5(E5 - E6) solar masses. Ambient gas densities are found to decrease with increasing core-hotspot distance, but have no redshift dependence. Overall, the results obtained with the sample of 31 sources studied here are consistent with those obtained earlier with smaller samples.

  17. Incidence of Second Malignancies Among Patients Treated With Proton Versus Photon Radiation

    SciTech Connect (OSTI)

    Chung, Christine S., E-mail: chungc1@sutterhealth.org [Department of Radiation Oncology, Alta Bates Summit Medical Center, Berkeley, California (United States); Yock, Torunn I. [Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States); Nelson, Kerrie [Department of Biostatistics, Boston University School of Public Health, Boston, Massachusetts (United States); Xu, Yang [Department of Health Care Policy, Harvard Medical School, Boston, Massachusetts (United States); Keating, Nancy L. [Department of Health Care Policy, Harvard Medical School, Boston, Massachusetts (United States); Department of General Internal Medicine, Brigham and Women's Hospital, Boston, Massachusetts (United States); Tarbell, Nancy J. [Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States); Office of the Executive Dean, Harvard Medical School, Boston, Massachusetts (United States)

    2013-09-01T23:59:59.000Z

    Purpose: Proton radiation, when compared with photon radiation, allows delivery of increased radiation dose to the tumor while decreasing dose to adjacent critical structures. Given the recent expansion of proton facilities in the United States, the long-term sequelae of proton therapy should be carefully assessed. The objective of this study was to compare the incidence of second cancers in patients treated with proton radiation with a population-based cohort of matched patients treated with photon radiation. Methods and Materials: We performed a retrospective cohort study of 558 patients treated with proton radiation from 1973 to 2001 at the Harvard Cyclotron in Cambridge, MA and 558 matched patients treated with photon therapy in the Surveillance, Epidemiology, and End Results (SEER) Program cancer registry. Patients were matched by age at radiation treatment, sex, year of treatment, cancer histology, and site. The main outcome measure was the incidence of second malignancies after radiation. Results: We matched 558 proton patients with 558 photon patients from the Surveillance, Epidemiology, and End Results registry. The median duration of follow-up was 6.7 years (interquartile range, 7.4) and 6.0 years (interquartile range, 9.3) in the proton and photon cohorts, respectively. The median age at treatment was 59 years in each cohort. Second malignancies occurred in 29 proton patients (5.2%) and 42 photon patients (7.5%). After we adjusted for sex, age at treatment, primary site, and year of diagnosis, proton therapy was not associated with an increased risk of second malignancy (adjusted hazard ratio, 0.52 [95% confidence interval, 0.32-0.85]; P=.009). Conclusions: The use of proton radiation therapy was not associated with a significantly increased risk of secondary malignancies compared with photon therapy. Longer follow-up of these patients is needed to determine if there is a significant decrease in second malignancies. Given the limitations of the study, these results should be viewed as hypothesis generating.

  18. Radiation Dose to the Lens During Craniospinal Irradiation-An Improvement in Proton Radiotherapy Technique

    SciTech Connect (OSTI)

    Cochran, David M. [Division of Health Sciences and Technology, Harvard Medical School and Massachusetts Institute of Technology, Cambridge, MA (United States); Yock, Torunn I.; Adams, Judith A. C. [Department of Radiation Oncology, Massachusetts General Hospital, Harvard Medical School, Boston, MA (United States); Tarbell, Nancy J. [Department of Radiation Oncology, Massachusetts General Hospital, Harvard Medical School, Boston, MA (United States)], E-mail: ntarbell@partners.org

    2008-04-01T23:59:59.000Z

    Purpose: To evaluate the effect of angle modification of cranial field proton beam therapy on the radiation dose delivered to the lens during craniospinal irradiation (CSI). Methods and Materials: Thirty-nine patients with central nervous system tumors who received CSI with a posterior fossa boost were analyzed for the radiation dose to the lens. Thirteen patients received cranial field treatment using standard opposed-lateral proton beams, and 26 patients received treatment with angled posterior-oblique proton beams. The lens dose in a test case also was evaluated by comparing conventional X-rays with the two proton beam planning methods by using a CMS/Xio three-dimensional planning system. Results: Substantial lens dose sparing was realized with the angling of the cranial proton beams 15{sup o}-20{sup o} to the posterior. In the 39 treated patients who were analyzed (median age, 7 years), average dose delivered to the lens was decreased by approximately 50% by angling of the proton beams, with the average maximum dose decreasing from 74% to 40% of the prescribed dose (p < 0.0001). Significant lens sparing was seen in patients 10 years and younger (median age, 6 years; p < 0.0001), whereas an insignificant decrease was seen in older patients (median age, 16 years; p = 0.14). With the opposed-lateral technique (median age, 6 years), the lens dose increased significantly with decreasing age (p = 0.002), whereas there was no effect of age on lens dose in the angled beam-treated group (median age, 8.5 years; p = 0.73). Conclusion: The present study clearly shows an advantage in sparing of the lens dose by angling the beams used during proton beam CSI. This effect is most pronounced in patients 10 years and younger because of anatomic effects of sinus development.

  19. R Coronae Borealis stars in the Galactic Bulge discovered by EROS-2

    E-Print Network [OSTI]

    P. Tisserand; J. B. Marquette; P. R. Wood; E. Lesquoy; J. P. Beaulieu; A. Milsztajn; C. Hamadache; C. Afonso; J. N. Albert; J. Andersen; R. Ansari; E. Aubourg; P. Bareyre; X. Charlot; C. Coutures; R. Ferlet; P. Fouqué; J. F. Glicenstein; B. Goldman; A. Gould; M. Gros; J. Haissinski; J. de Kat; L. Le Guillou; C. Loup; C. Magneville; E. Maurice; A. Maury; M. Moniez; N. Palanque-Delabrouille; O. Perdereau; Y. Rahal; J. Rich; M. Spiro; A. Vidal-Madjar; S. Zylberajch

    2008-01-11T23:59:59.000Z

    Rare types of variable star may give unique insight into short-lived stages of stellar evolution. The systematic monitoring of millions of stars and advanced light curve analysis techniques of microlensing surveys make them ideal for discovering also such rare variable stars. One example is the R Coronae Borealis (RCB) stars, a rare type of evolved carbon-rich supergiant. We have conducted a systematic search of the EROS-2 database for the Galactic catalogue Bulge and spiral arms to find Galactic RCB stars. The light curves of $\\sim$100 million stars, monitored for 6.7 years (from July 1996 to February 2003), have been analysed to search for the main signature of RCB stars, large and rapid drops in luminosity. Follow-up spectroscopy has been used to confirm the photometric candidates. We have discovered 14 new RCB stars, all in the direction of the Galactic Bulge, bringing the total number of confirmed Galactic RCB stars to about 51. After reddening correction, the colours and absolute magnitudes of at least 9 of the stars are similar to those of Magellanic RCB stars. This suggests that these stars are in fact located in the Galactic Bulge, making them the first RCB stars discovered in the Bulge. The localisation of the 5 remaining RCBs is more uncertain: 4 are either located behind the Bulge at an estimated maximum distance of 14 kpc or have an unusual thick circumstellar shell; the other is a DY Per RCB which may be located in the Bulge, even if it is fainter than the known Magellanic DY Per. From the small scale height found using the 9 new Bulge RCBs, $61

  20. Limits on the Macho Content of the Galactic Halo from the EROS-2 Survey of the Magellanic Clouds

    E-Print Network [OSTI]

    P. Tisserand; L. Le Guillou; C. Afonso; J. N. Albert; J. Andersen; R. Ansari; E. Aubourg; P. Bareyre; J. P. Beaulieu; X. Charlot; C. Coutures; R. Ferlet; P. Fouqué; J. F. Glicenstein; B. Goldman; A. Gould; D. Graff; M. Gros; J. Haissinski; C. Hamadache; J. de Kat; T. Lasserre; E. Lesquoy; C. Loup; C. Magneville; J. B. Marquette; E. Maurice; A. Maury; A. Milsztajn; M. Moniez; N. Palanque-Delabrouille; O. Perdereau; Y. R. Rahal; J. Rich; M. Spiro; A. Vidal-Madjar; L. Vigroux; S. Zylberajch

    2007-04-19T23:59:59.000Z

    The EROS-2 project was designed to test the hypothesis that massive compact halo objects (the so-called ``machos'') could be a major component of the dark matter halo of the Milky Way galaxy. To this end, EROS-2 monitored over 6.7 years $33\\times10^6$ stars in the Magellanic clouds for microlensing events caused by such objects. In this work, we use only a subsample of $7\\times10^6$ bright stars spread over $84 \\deg^2$ of the LMC and $9 \\deg^2$ of the SMC. The strategy of using only bright stars helps to discriminate against background events due to variable stars and allows a simple determination of the effects of source confusion (blending). The use of a large solid angle makes the survey relatively insensitive to effects that could make the optical depth strongly direction dependent. Using this sample of bright stars, only one candidate event was found, whereas $\\sim39$ events would have been expected if the Halo were entirely populated by objects of mass $M\\sim0.4M_{\\odot}$. Combined with the results of EROS-1, this implies that the optical depth toward the Large Magellanic Cloud (\\object{LMC}) due to such lenses is $\\tau<0.36\\times10^{-7}$ (95%CL), corresponding to a fraction of the halo mass of less than 8%. This optical depth is considerably less than that measured by the MACHO collaboration in the central region of the LMC. More generally, machos in the mass range $0.6\\times10^{-7}M_\\odot

  1. Evaluation of potential severe accidents during low power and shutdown operations at Grand Gulf, Unit 1. Volume 5: Analysis of core damage frequency from seismic events for plant operational state 5 during a refueling outage

    SciTech Connect (OSTI)

    Budnitz, R.J. [Future Resources Associates, Inc., Berkeley, CA (United States); Davis, P.R. [PRD Consulting (United States); Ravindra, M.K.; Tong, W.H. [EQE International, Inc., Irvine, CA (United States)

    1994-08-01T23:59:59.000Z

    In 1989 the US Nuclear Regulatory Commission (NRC) initiated an extensive program to examine carefully the potential risks during low-power and shutdown operations. The program included two parallel projects, one at Sandia National Laboratories studying a boiling water reactor (Grand Gulf), and the other at Brookhaven National Laboratory studying a pressurized water reactor (Surry Unit 1). Both the Sandia and Brookhaven projects have examined only accidents initiated by internal plant faults---so-called ``internal initiators.`` This project, which has explored the likelihood of seismic-initiated core damage accidents during refueling outage conditions, is complementary to the internal-initiator analyses at Brookhaven and Sandia. This report covers the seismic analysis at Grand Gulf. All of the many systems modeling assumptions, component non-seismic failure rates, and human effort rates that were used in the internal-initiator study at Grand Gulf have been adopted here, so that the results of the study can be as comparable as possible. Both the Sandia study and this study examine only one shutdown plant operating state (POS) at Grand Gulf, namely POS 5 representing cold shutdown during a refueling outage. This analysis has been limited to work analogous to a level-1 seismic PRA, in which estimates have been developed for the core-damage frequency from seismic events during POS 5. The results of the analysis are that the core-damage frequency for earthquake-initiated accidents during refueling outages in POS 5 is found to be quite low in absolute terms, less than 10{sup {minus}7}/year.

  2. Environmental Cleanup of the Idaho National Laboratory Status Report

    SciTech Connect (OSTI)

    Schubert, A.L. [CH2M.WG Idaho, LLC, Idaho Falls, Idaho (United States)

    2008-07-01T23:59:59.000Z

    This paper describes the status of the cleanup of the U.S. Department of Energy's Idaho National Laboratory site (INL). On May 1, 2005 CH2M.WG Idaho, LLC (CWI) began its 7-year, $2.4 billion cleanup of the INL. When the work is completed, 3,406,871 liters (900,000 gallons) of sodium-bearing waste will have been treated; 15 high-level waste tanks will have been grouted and Resource Conservation and Recovery Act (RCRA)- closed; more than 200 facilities will have been demolished or disposed of, including three reactors, several spent fuel basins, and hot cells; thousands of containers of buried transuranic waste will have been retrieved; more than 8,000 cubic meters (10,464 cubic yards) of contact-handled transuranic waste and more than 500 cubic meters (654 cubic yards) of remote-handled transuranic waste will have been characterized, packaged, and shipped offsite; almost 200 release sites and voluntary consent order tank systems will have been remediated; and 3,178 units of spent fuel will have been moved from wet to dry storage. In 2007, CWI began the construction of the Integrated Waste Treatment Unit that will treat the sodium-bearing waste for eventual disposal; removed and disposed the 112-ton Engineering Test Reactor vessel; demolished all significant radiological facilities at Test Area North; continued the exhumation of buried transuranic wastes from the Subsurface Disposal Area at the Radioactive Waste Management Complex; shipped the first of hundreds of containers of remote-handled transuranic waste to the Waste Isolation Pilot Plant; disposed of thousands of cubic meters of low-level and low-level mixed radioactive wastes both onsite and offsite while meeting all regulatory cleanup objectives. (author)

  3. Observations of the Temperature Dependent Response of Ozone to NOx Reductions in an Urban Plume

    SciTech Connect (OSTI)

    LaFranchi, B W; Goldstein, A H; Cohen, R C

    2011-01-25T23:59:59.000Z

    Observations of NO{sub x} in the Sacramento, CA region show that mixing ratios decreased by 30% between 2001 and 2008. Here we use an observation-based method to quantify net ozone production rates in the outflow from the Sacramento metropolitan region and examine the O{sub 3} decrease resulting from reductions in NO{sub x} emissions. This observational method does not rely on assumptions about detailed chemistry of ozone production, rather it is an independent means to verify and test these assumptions. We use an instantaneous steady-state model as well as a detailed 1-D plume model to aid in interpretation of the ozone production inferred from observations. In agreement with the models, the observations show that early in the plume, the NO{sub x} dependence for O{sub x} (O{sub x} = O{sub 3}+NO{sub 2}) production is strongly coupled with temperature, suggesting that temperature dependent biogenic VOC emissions can drive O{sub x} production between NO{sub x}-limited and NO{sub x}-suppressed regimes. As a result, NO{sub x} reductions were found to be most effective at higher temperatures over the 7 year period. We show that violations of the California 1-hour O{sub 3} standard (90 ppb) in the region have been decreasing linearly with decreases in NO{sub x} (at a given temperature) and predict that reductions of NO{sub x} concentrations (and presumably emissions) by an additional 30% (relative to 2007 levels) will eliminate violations of the state 1 hour standard in the region. If current trends continue, a 30% decrease in NO{sub x} is expected by 2012, and an end to violations of the 1 hour standard in the Sacramento region appears to be imminent.

  4. Erectile Function Durability Following Permanent Prostate Brachytherapy

    SciTech Connect (OSTI)

    Taira, Al V. [Department of Radiation Oncology, University of Washington, Seattle, WA (United States); Merrick, Gregory S., E-mail: gmerrick@urologicresearchinstitute.or [Schiffler Cancer Center, Wheeling Jesuit University, Wheeling, West Virginia (United States); Galbreath, Robert W.; Butler, Wayne M. [Schiffler Cancer Center, Wheeling Jesuit University, Wheeling, West Virginia (United States); Wallner, Kent E. [Puget Sound Healthcare Corporation, Group Health Cooperative, University of Washington, Seattle, WA (United States); Kurko, Brian S.; Anderson, Richard; Lief, Jonathan H. [Schiffler Cancer Center, Wheeling Jesuit University, Wheeling, West Virginia (United States)

    2009-11-01T23:59:59.000Z

    Purpose: To evaluate long-term changes in erectile function following prostate brachytherapy. Methods and Materials: This study included 226 patients with prostate cancer and preimplant erectile function assessed by the International Index of Erectile Function-6 (IIEF-6) who underwent brachytherapy in two prospective randomized trials between February 2001 and January 2003. Median follow-up was 6.4 years. Pre- and postbrachytherapy potency was defined as IIEF-6 >= 13 without pharmacologic or mechanical support. The relationship among clinical, treatment, and dosimetric parameters and erectile function was examined. Results: The 7-year actuarial rate of potency preservation was 55.6% with median postimplant IIEF of 22 in potent patients. Potent patients were statistically younger (p = 0.014), had a higher preimplant IIEF (p < 0.001), were less likely to be diabetic (p = 0.002), and were more likely to report nocturnal erections (p = 0.008). Potency preservation in men with baseline IIEF scores of 29-30, 24-28, 18-23, and 13-17 were 75.5% vs. 73.6%, 51.7% vs. 44.8%, 48.0% vs. 40.0%, and 23.5% vs. 23.5% in 2004 vs. 2008. In multivariate Cox regression analysis, preimplant IIEF, hypertension, diabetes, prostate size, and brachytherapy dose to proximal penis strongly predicted for potency preservation. Impact of proximal penile dose was most pronounced for men with IIEF of 18-23 and aged 60-69. A significant minority of men who developed postimplant impotence ultimately regained erectile function. Conclusion: Potency preservation and median IIEF scores following brachytherapy are durable. Thoughtful dose sparing of proximal penile structures and early penile rehabilitation may further improve these results.

  5. Multi Megawatt Power System Analysis Report

    SciTech Connect (OSTI)

    Longhurst, Glen Reed; Harvego, Edwin Allan; Schnitzler, Bruce Gordon; Seifert, Gary Dean; Sharpe, John Phillip; Verrill, Donald Alan; Watts, Kenneth Donald; Parks, Benjamin Travis

    2001-11-01T23:59:59.000Z

    Missions to the outer planets or to near-by planets requiring short times and/or increased payload carrying capability will benefit from nuclear power. A concept study was undertaken to evaluate options for a multi-megawatt power source for nuclear electric propulsion. The nominal electric power requirement was set at 15 MWe with an assumed mission profile of 120 days at full power, 60 days in hot standby, and another 120 days of full power, repeated several times for 7 years of service. Of the numerous options considered, two that appeared to have the greatest promise were a gas-cooled reactor based on the NERVA Derivative design, operating a closed cycle Brayton power conversion system; and a molten lithium-cooled reactor based on SP-100 technology, driving a boiling potassium Rankine power conversion system. This study examined the relative merits of these two systems, seeking to optimize the specific mass. Conclusions were that either concept appeared capable of approaching the specific mass goal of 3-5 kg/kWe estimated to be needed for this class of mission, though neither could be realized without substantial development in reactor fuels technology, thermal radiator mass efficiency, and power conversion and distribution electronics and systems capable of operating at high temperatures. Though the gas-Brayton systems showed an apparent advantage in specific mass, differences in the degree of conservatism inherent in the models used suggests expectations for the two approaches may be similar. Brayton systems eliminate the need to deal with two-phase flows in the microgravity environment of space.

  6. The use of stored carbon reserves in growth of temperate tree roots and leaf buds: Analyses using radiocarbon measurements and modeling

    SciTech Connect (OSTI)

    Gaudinski, J.B.; Torn, M.S.; Riley, W.J.; Swanston, C.; Trumbore, S.E.; Joslin, J.D.; Majdi, H.; Dawson, T.E.; Hanson, P.J.

    2009-02-01T23:59:59.000Z

    Characterizing the use of carbon (C) reserves in trees is important for understanding regional and global C cycles, stress responses, asynchrony between photosynthetic activity and growth demand, and isotopic exchanges in studies of tree physiology and ecosystem C cycling. Using an inadvertent, whole-ecosystem radiocarbon ({sup 14}C) release in a temperate deciduous oak forest and numerical modeling, we estimated that the mean age of stored C used to grow both leaf buds and new roots is 0.7 years and about 55% of new-root growth annually comes from stored C. Therefore, the calculated mean age of C used to grow new-root tissue is {approx}0.4 years. In short, new roots contain a lot of stored C but it is young in age. Additionally, the type of structure used to model stored C input is important. Model structures that did not include storage, or that assumed stored and new C mixed well (within root or shoot tissues) before being used for root growth, did not fit the data nearly as well as when a distinct storage pool was used. Consistent with these whole-ecosystem labeling results, the mean age of C in new-root tissues determined using 'bomb-{sup 14}C' in three additional forest sites in North America and Europe (one deciduous, two coniferous) was less than 1-2 years. The effect of stored reserves on estimated ages of fine roots is unlikely to be large in most natural abundance isotope studies. However, models of root C dynamics should take stored reserves into account, particularly for pulse-labeling studies and fast-cycling roots (<1 years).

  7. Whole-pelvis, 'mini-pelvis,' or prostate-only external beam radiotherapy after neoadjuvant and concurrent hormonal therapy in patients treated in Radiation Therapy Oncology Group 9413 trial

    SciTech Connect (OSTI)

    Roach, Mack [University of California San Francisco, San Francisco, CA (United States)]. E-mail: roach@radonc17.ucsf.edu; De Silvio, Michelle [RTOG Statistical Headquarters, Philadelphia, PA (United States); Valicenti, Richard [Thomas Jefferson University, Philadelphia, PA (United States); Grignon, David [Wayne State University, Detroit, MI (United States); Asbell, Sucha O. [Albert Einstein Medical Center, Philadelphia, PA (United States); Lawton, Colleen [Medical College of Wisconsin, Milwaukee, WI (United States); Thomas, Charles R. [Oregon Health and Sciences University, Portland OR (United States); Shipley, William U. [Massachusetts General Hospital, Boston, MA (United States)

    2006-11-01T23:59:59.000Z

    Purpose: Radiation Therapy Oncology Group (RTOG) 9413 trial demonstrated a better progression-free survival (PFS) with whole-pelvis (WP) radiotherapy (RT) compared with prostate-only (PO) RT. This secondary analysis was undertaken to determine whether 'mini-pelvis' (MP; defined as {>=}10 x 11 cm but <11 x 11 cm) RT resulted in progression-free survival (PFS) comparable to that of WP RT. To avoid a timing bias, this analysis was limited to patients receiving neoadjuvant and concurrent hormonal therapy (N and CHT) in Arms 1 and 2 of the study. Methods and Materials: Eligible patients had a risk of lymph node (LN) involvement >15%. Neoadjuvant and concurrent hormonal therapy (N and CHT) was administered 2 months before and during RT for 4 months. From April 1, 1995, to June 1, 1999, a group of 325 patients were randomized to WP RT + N and CHT and another group of 324 patients were randomized to receive PO RT + N and CHT. Patients randomized to PO RT were dichotomized by median field size (10 x 11 cm), with the larger field considered an 'MP' field and the smaller a PO field. Results: The median PFS was 5.2, 3.7, and 2.9 years for WP, MP, and PO fields, respectively (p = 0.02). The 7-year PFS was 40%, 35%, and 27% for patients treated to WP, MP, and PO fields, respectively. There was no association between field size and late Grade 3+ genitourinary toxicity but late Grade 3+ gastrointestinal RT complications correlated with increasing field size. Conclusions: This subset analysis demonstrates that RT field size has a major impact on PFS, and the findings support comprehensive nodal treatment in patients with a risk of LN involvement of >15%.

  8. Intensity Modulated Radiation Therapy With Dose Painting to Treat Rhabdomyosarcoma

    SciTech Connect (OSTI)

    Yang, Joanna C.; Dharmarajan, Kavita V. [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States)] [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Wexler, Leonard H. [Department of Pediatrics, Memorial Sloan-Kettering Cancer Center, New York, New York (United States)] [Department of Pediatrics, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); La Quaglia, Michael P. [Department of Surgery, Memorial Sloan-Kettering Cancer Center, New York, New York (United States)] [Department of Surgery, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Happersett, Laura [Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, New York (United States)] [Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Wolden, Suzanne L., E-mail: woldens@mskcc.org [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States)

    2012-11-01T23:59:59.000Z

    Purpose: To examine local control and patterns of failure in rhabdomyosarcoma patients treated with intensity modulated radiation therapy (RT) with dose painting (DP-IMRT). Patients and Methods: A total of 41 patients underwent DP-IMRT with chemotherapy for definitive treatment. Nineteen also underwent surgery with or without intraoperative RT. Fifty-six percent had alveolar histologic features. The median interval from beginning chemotherapy to RT was 17 weeks (range, 4-25). Very young children who underwent second-look procedures with or without intraoperative RT received reduced doses of 24-36 Gy in 1.4-1.8-Gy fractions. Young adults received 50.4 Gy to the primary tumor and lower doses of 36 Gy in 1.8-Gy fractions to at-risk lymph node chains. Results: With 22 months of median follow-up, the actuarial local control rate was 90%. Patients aged {<=}7 years who received reduced overall and fractional doses had 100% local control, and young adults had 79% (P=.07) local control. Three local failures were identified in young adults whose primary target volumes had received 50.4 Gy in 1.8-Gy fractions. Conclusions: DP-IMRT with lower fractional and cumulative doses is feasible for very young children after second-look procedures with or without intraoperative RT. DP-IMRT is also feasible in adolescents and young adults with aggressive disease who would benefit from prophylactic RT to high-risk lymph node chains, although dose escalation might be warranted for improved local control. With limited follow-up, it appears that DP-IMRT produces local control rates comparable to those of sequential IMRT in patients with rhabdomyosarcoma.

  9. Review of Adjuvant Radiochemotherapy for Resected Pancreatic Cancer and Results From Mayo Clinic for the 5th JUCTS Symposium

    SciTech Connect (OSTI)

    Miller, Robert C. [Department of Radiation Oncology, Mayo Clinic, Rochester, Minnesota (United States)], E-mail: miller.robert@mayo.edu; Iott, Matthew J.; Corsini, Michele M. [Department of Radiation Oncology, Mayo Clinic, Rochester, Minnesota (United States)

    2009-10-01T23:59:59.000Z

    Purpose: To present an overview of Phase III trials in adjuvant therapy for pancreatic cancer and review outcomes at the Mayo Clinic after adjuvant radiochemotherapy (RT/CT) for resected pancreatic cancer. Methods and Materials: A literature review and a retrospective review of 472 patients who underwent an R0 resection for T1-3N0-1M0 invasive carcinoma of the pancreas from 1975 to 2005 at the Mayo Clinic, Rochester, MN. Patients with metastatic or unresectable disease at the time of surgery, positive surgical margins, or indolent tumors and those treated with intraoperative radiotherapy were excluded from the analysis. Median radiotherapy dose was 50.4Gy in 28 fractions, with 98% of patients receiving concurrent 5-fluorouracil- based chemotherapy. Results: Median follow-up was 2.7 years. Median overall survival (OS) was 1.8 years. Median OS after adjuvant RT/CT was 2.1 vs. 1.6 years for surgery alone (p = 0.001). The 2-y OS was 50% vs. 39%, and 5-y was 28% vs. 17% for patients receiving RT/CT vs. surgery alone. Univariate and multivariate analysis revealed that adverse prognostic factors were positive lymph nodes (risk ratio [RR] 1.3, p < 0.001) and high histologic grade (RR 1.2, p < 0.001). T3 tumor status was found significant on univariate analysis only (RR 1.1, p = 0.07). Conclusions: Results from recent clinical trials support the use of adjuvant chemotherapy in resected pancreatic cancer. The role of radiochemotherapy in adjuvant treatment of pancreatic cancer remains a topic of debate. Results from the Mayo Clinic suggest improved outcomes after the administration of adjuvant radiochemotherapy after a complete resection of invasive pancreatic malignancies.

  10. Metallic Stents for Tracheobronchial Pathology Treatment

    SciTech Connect (OSTI)

    Serrano, Carolina, E-mail: carolina.serrano@unizar.es [University of Zaragoza, Surgical Pathology Unit, Animal Pathology Department (Spain)] [University of Zaragoza, Surgical Pathology Unit, Animal Pathology Department (Spain); Laborda, Alicia, E-mail: alaborda@unizar.es [University of Zaragoza, Minimally Invasive Techniques Research Group (GITMI) (Spain)] [University of Zaragoza, Minimally Invasive Techniques Research Group (GITMI) (Spain); Lozano, Juan M., E-mail: juamauloz@gmail.com [Marly Clinic, Radiology Department (Colombia); Caballero, Hugo, E-mail: hugocaballero2007@gmail.com [Marly Clinic, Pulmonology Department (Colombia)] [Marly Clinic, Pulmonology Department (Colombia); Sebastian, Antonio, E-mail: antonio.sebastian@ono.es [Lozano Blesa Clinical University Hospital, Pulmonology Department (Spain)] [Lozano Blesa Clinical University Hospital, Pulmonology Department (Spain); Lopera, Jorge, E-mail: lopera@uthscsa.edu [Health Science Center, Interventional Radiology Deparment (United States)] [Health Science Center, Interventional Radiology Deparment (United States); Gregorio, Miguel Angel de, E-mail: mgregori@unizar.es [University of Zaragoza, Minimally Invasive Techniques Research Group (GITMI) (Spain)

    2013-12-15T23:59:59.000Z

    Purpose: To present the 7-year experience of the treatment of benign and malignant tracheobronchial stenoses using metallic stents. Patients and Methods: One hundred twenty-three stents were inserted in 86 patients (74 benign and 12 malignant stenoses). Ninety-seven stents were placed in the trachea and 26 in the bronchi. The procedures were performed under fluoroscopic and flexible bronchoscopic guidance with the patient under light sedation. In cases of severe stenotic lesions or obstructions, laser resection was performed before stent placement. Clinical and functional pulmonary data were recorded before and 3 months after the procedure. Follow-up involved clinical data and radiographic techniques at 48 h and at 1-, 3-, 6-, and 12-month intervals. Results: The technical success was 100 %. Dyspnea disappearance, forced expiratory volume in the first second, and pulmonary functional data improvement was observed in all patients (p < 0.001). Complications were detected in 23 patients (26.7 %). Mean follow-up time was 6.3 {+-} 1.2 months in patients with malignant lesions and 76.2 {+-} 2.3 months patients with in benign lesions. By the end of the study, 100 % of patients with malignant pathology and 6.7 % of patients with benign lesions had died. Conclusion: Endoluminal treatment of tracheobronchial stenosis with metallic stents is a therapeutic alternative in patients who are poor candidates for surgery. In unresectable malignant lesions, the benefit of metallic stenting is unquestionable. In benign lesions, the results are satisfactory, but sometimes other interventions are required to treat complications. New stent technology may improve these results.

  11. Gamma Knife Radiosurgery for Patients With Nonfunctioning Pituitary Adenomas: Results From a 15-Year Experience

    SciTech Connect (OSTI)

    Pollock, Bruce E. [Department of Neurological Surgery, Mayo Clinic College of Medicine, Rochester, MN (United States); Department of Radiation Oncology, Mayo Clinic College of Medicine, Rochester, MN (United States)], E-mail: pollock.bruce@mayo.edu; Cochran, Joseph [Department of Neurological Surgery, Mayo Clinic College of Medicine, Rochester, MN (United States); Natt, Neena [Department of Endocrinology, Diabetes and Metabolism, Mayo Clinic College of Medicine, Rochester, MN (United States); Brown, Paul D. [Department of Radiation Oncology, Mayo Clinic College of Medicine, Rochester, MN (United States); Erickson, Dana [Department of Endocrinology, Diabetes and Metabolism, Mayo Clinic College of Medicine, Rochester, MN (United States); Link, Michael J. [Department of Neurological Surgery, Mayo Clinic College of Medicine, Rochester, MN (United States); Garces, Yolanda I.; Foote, Robert L.; Stafford, Scott L.; Schomberg, Paula J. [Department of Radiation Oncology, Mayo Clinic College of Medicine, Rochester, MN (United States)

    2008-04-01T23:59:59.000Z

    Purpose: To evaluate the efficacy and complications of stereotactic radiosurgery for patients with nonfunctioning pituitary adenomas (NFA). Methods and Materials: This was a retrospective review of 62 patients with NFA undergoing radiosurgery between 1992 and 2004, of whom 59 (95%) underwent prior tumor resection. The median treatment volume was 4.0 cm{sup 3} (range, 0.8-12.9). The median treatment dose to the tumor margin was 16 Gy (range, 11-20). The median maximum point dose to the optic apparatus was 9.5 Gy (range, 5.0-12.6). The median follow-up period after radiosurgery was 64 months (range, 23-161). Results: Tumor size decreased for 37 patients (60%) and remained unchanged for 23 patients (37%). Two patients (3%) had tumor growth outside the prescribed treatment volume and required additional treatment (fractionated radiation therapy, n = 1; repeat radiosurgery, n 1). Tumor growth control was 95% at 3 and 7 years after radiosurgery. Eleven (27%) of 41 patients with normal (n = 30) or partial (n = 11) anterior pituitary function before radiosurgery developed new deficits at a median of 24 months after radiosurgery. The risk of developing new anterior pituitary deficits at 5 years was 32%. The 5-year risk of developing new anterior pituitary deficits was 18% for patients with a tumor volume of {<=}4.0 cm{sup 3} compared with 58% for patients with a tumor volume >4.0 cm{sup 3} (risk ratio 4.5; 95% confidence interval = 1.3-14.9, p = 0.02). No patient had a decline in visual function. Conclusions: Stereotactic radiosurgery is effective in the management of patients with residual or recurrent NFA, although longer follow-up is needed to evaluate long-term outcomes. The primary complication is hypopituitarism, and the risk of developing new anterior pituitary deficits correlates with the size of the irradiated tumor.

  12. Long-Term Follow-Up of Dose-Adapted and Reduced-Field Radiotherapy With or Without Chemotherapy for Central Nervous System Germinoma

    SciTech Connect (OSTI)

    Jensen, Ashley W. [Department of Radiation Oncology, Mayo Clinic, Rochester, MN (United States); Issa Laack, Nadia N., E-mail: laack.nadia@mayo.ed [Department of Radiation Oncology, Mayo Clinic, Rochester, MN (United States); Buckner, Jan C. [Department of Oncology, Mayo Clinic, Rochester, MN (United States); Schomberg, Paula J. [Department of Radiation Oncology, Mayo Clinic, Rochester, MN (United States); Wetmore, Cynthia J. [Department of Pediatric and Adolescent Medicine, Mayo Clinic, Rochester, MN (United States); Brown, Paul D. [Department of Radiation Oncology, Mayo Clinic, Rochester, MN (United States)

    2010-08-01T23:59:59.000Z

    Purpose: To update our institutional experience with neoadjuvant chemotherapy and minimized radiotherapy vs. radiation monotherapy for intracranial germinoma. Methods and Materials: We retrospectively reviewed records of 59 patients with diagnosis of primary intracranial germinoma between 1977 and 2007. Treatment was irradiation alone or neoadjuvant platinum-based chemotherapy and local irradiation (initial tumor plus margin) for patients with localized complete response and reduced-dose craniospinal irradiation for others. Results: For the chemoradiotherapy group (n = 28), median follow-up was 7 years. No patient died. The freedom from progression (FFP) rate was 88% at 5 years and 80% at 10 years. In 4 patients, disease recurred 1.1 to 6.8 years after diagnosis. All were young male patients who received 30.6 Gy to local fields after complete response to chemotherapy. The FFP rate was 88% for local irradiation vs. 100% for more extensive fields (p = .06). For the radiotherapy-alone group (n = 31), median follow-up was 15 years. Overall and disease-free survival rates were 93% and 93% at 5 years and 90% and 87% at 15 years. In 5 patients, disease recurred 1.1 to 4.9 years after diagnosis. Most patients in this group were young men 18 to 23 years of age with suprasellar primary disease treated with about 50 Gy to local fields. The FFP rate was 44% for local irradiation vs. 100% for more extensive fields (p < .01). Conclusions: The addition of neoadjuvant chemotherapy to local-field radiotherapy reduced central nervous system cancer recurrence when high-risk patients were excluded by thorough pretreatment staging. There was trend toward improved central nervous system tumor control when larger fields (whole brain, whole ventricle, or craniospinal axis) were used.

  13. Long-term Outcomes of Percutaneous Venoplasty and Gianturco Stent Placement to Treat Obstruction of the Inferior Vena Cava Complicating Liver Transplantation

    SciTech Connect (OSTI)

    Lorenz, Jonathan M., E-mail: jlorenz@radiology.bsd.uchicago.edu; Beek, Darren van; Funaki, Brian; Ha, Thuong G. Van; Zangan, Stephen; Navuluri, Rakesh; Leef, Jeffery A. [University of Chicago (United States)

    2013-05-11T23:59:59.000Z

    PurposeEvaluation of long-term outcomes of venoplasty and Gianturco stents to treat inferior vena cava (IVC) obstruction after liver transplantation.MethodsWe retrospectively analyzed records from 33 consecutive adult patients referred with the intent to treat suspected IVC obstruction after liver transplantation. Treatment was performed for occlusion or stenosis with a gradient exceeding 3 mmHg. The primary treatment was venoplasty and, if refractory, Gianturco stent placement. Recurrence prompted repeat venoplasty or stent placement.ResultsOf the 33 patients, 25 (aged 46.9 ± 12.2 years) required treatment at a mean of 2.3 years (14 days to 20.3 years) after transplantation. For technically successful cases, primary treatment was venoplasty alone (14) or with stent placement (10). Technical success was 96 % (24 of 25) reflecting failure to cross one occlusion. Clinical success was 88 % (22 of 25) reflecting the technical failure and two that died of unrelated complications within 5 weeks. Cumulative primary patencies were 57.1 % at 6 months (n = 21) and 51.4 % at 1 (n = 10), 3 (n = 7), 5 (n = 6), and 7 (n = 5) years. Cumulative primary assisted patency was 95.2 % at 6 months (n = 21) and at 1 (n = 15), 3 (n = 9), 5 (n = 8), and 7 (n = 8) years. The 17 patients stented for refractory (n = 10) or recurrent (n = 7) stenosis had cumulative primary and primary assisted patencies of 86.0 and 100 %, respectively, from 6 months (n = 14) to 7 years (n = 3). No major complications occurred; one fractured stent was observed after 11.6 years.ConclusionFor IVC obstruction following liver transplantation, excellent long-term outcomes can be achieved by venoplasty and Gianturco stent placement.

  14. The MACHO Project HST Follow-Up: The Large Magellanic Cloud Microlensing Source Stars

    SciTech Connect (OSTI)

    Nelson, C.A.; /LLNL, Livermore /UC, Berkeley; Drake, A.J.; /Caltech; Cook, K.H.; /LLNL, Livermore /UC, Berkeley; Bennett, D.P.; /Caltech /Notre Dame U.; Popowski, P.; /Garching, Max Planck Inst.; Dalal, N.; /Toronto U.; Nikolaev, S.; /LLNL, Livermore; Alcock, C.; /Caltech /Harvard-Smithsonian Ctr. Astrophys.; Axelrod, T.S.; /Arizona U.; Becker, A.C. /Washington U., Seattle; Freeman, K.C.; /Res. Sch. Astron. Astrophys., Weston Creek; Geha, M.; /Yale U.; Griest, K.; /UC, San Diego; Keller, S.C.; /LLNL, Livermore; Lehner, M.J.; /Harvard-Smithsonian Ctr. Astrophys. /Taipei, Inst. Astron. Astrophys.; Marshall, S.L.; /SLAC; Minniti, D.; /Rio de Janeiro, Pont. U. Catol. /Vatican Astron. Observ.; Pratt, M.R.; /Aradigm, Hayward; Quinn, P.J.; /Western Australia U.; Stubbs, C.W.; /UC, Berkeley /Harvard U.; Sutherland, W.; /Oxford U. /Oran, Sci. Tech. U. /Garching, Max Planck Inst. /McMaster U.

    2009-06-25T23:59:59.000Z

    We present Hubble Space Telescope (HST) WFPC2 photometry of 13 microlensed source stars from the 5.7 year Large Magellanic Cloud (LMC) survey conducted by the MACHO Project. The microlensing source stars are identified by deriving accurate centroids in the ground-based MACHO images using difference image analysis (DIA) and then transforming the DIA coordinates to the HST frame. None of these sources is coincident with a background galaxy, which rules out the possibility that the MACHO LMC microlensing sample is contaminated with misidentified supernovae or AGN in galaxies behind the LMC. This supports the conclusion that the MACHO LMC microlensing sample has only a small amount of contamination due to non-microlensing forms of variability. We compare the WFPC2 source star magnitudes with the lensed flux predictions derived from microlensing fits to the light curve data. In most cases the source star brightness is accurately predicted. Finally, we develop a statistic which constrains the location of the Large Magellanic Cloud (LMC) microlensing source stars with respect to the distributions of stars and dust in the LMC and compare this to the predictions of various models of LMC microlensing. This test excludes at {approx}> 90% confidence level models where more than 80% of the source stars lie behind the LMC. Exotic models that attempt to explain the excess LMC microlensing optical depth seen by MACHO with a population of background sources are disfavored or excluded by this test. Models in which most of the lenses reside in a halo or spheroid distribution associated with either the Milky Way or the LMC are consistent which these data, but LMC halo or spheroid models are favored by the combined MACHO and EROS microlensing results.

  15. Probing Neutrino Oscillation Parameters using High Power Superbeam from ESS

    E-Print Network [OSTI]

    Sanjib Kumar Agarwalla; Sandhya Choubey; Suprabh Prakash

    2015-01-04T23:59:59.000Z

    A high-power neutrino superbeam experiment at the ESS facility has been proposed such that the source-detector distance falls at the second oscillation maximum, giving very good sensitivity towards establishing CP violation. In this work, we explore the comparative physics reach of the experiment in terms of leptonic CP-violation, precision on atmospheric parameters, non-maximal theta23, and its octant for a variety of choices for the baselines. We also vary the neutrino vs. the anti-neutrino running time for the beam, and study its impact on the physics goals of the experiment. We find that for the determination of CP violation, 540 km baseline with 7 years of neutrino and 3 years of anti-neutrino (7nu+3nubar) run-plan performs the best and one expects a 5sigma sensitivity to CP violation for 48% of true values of deltaCP. The projected reach for the 200 km baseline with 7nu+3nubar run-plan is somewhat worse with 5sigma sensitivity for 34% of true values of deltaCP. On the other hand, for the discovery of a non-maximal theta23 and its octant, the 200 km baseline option with 7nu+3nubar run-plan performs significantly better than the other baselines. A 5sigma determination of a non-maximal theta23 can be made if the true value of sin^2theta23 lesssim 0.45 or sin^2theta23 gtrsim 0.57. The octant of theta23 could be resolved at 5sigma if the true value of sin^2theta23 lesssim 0.43 or gtrsim 0.59, irrespective of deltaCP.

  16. Clinical-Pathologic Features and Long-Term Outcomes of Tubular Carcinoma of the Breast Compared With Invasive Ductal Carcinoma Treated With Breast Conservation Therapy

    SciTech Connect (OSTI)

    Liu, Gene-Fu F. [Yale University School of Medicine, New Haven, CT (United States); Yang Qifeng [Department of Breast Surgery, Qilu Hospital, Shandong University, Jinan (China); Haffty, Bruce G. [UMDNJ-Robert Wood Johnson School of Medicine, and Department of Radiation Oncology, Cancer Institute of New Jersey, New Brunswick, NJ (United States); Moran, Meena S., E-mail: meena.moran@yale.ed [Department of Therapeutic Radiology, Yale University School of Medicine, New Haven, CT (United States)

    2009-12-01T23:59:59.000Z

    Purpose: To evaluate our institutional experience of treating tubular carcinoma of the breast (TC) and invasive ductal carcinoma (IDC) with conservative surgery and radiation therapy, to compare clinical-pathologic features and long-term outcomes. Methods and Materials: A review of our institution's tumor registry from 1975 to 2007, followed by a central pathology review of available slides, yielded 71 cases of Stage I/II TC and 2,238 cases of Stage I/II IDC treated with breast conservation therapy. Clinical-pathologic features and outcomes were analyzed by subtype to detect significant differences. Results: The median follow-up was 7 years. The TC cohort presented more frequently with pT1 disease (97% vs. 80%, p = 0.0007), pN0 disease (95% vs. 74%, p = 0.0004), hormone-receptor positivity (ER+, 89% vs. 62%, p = 0.0001; PR+, 81% vs. 52%, p = 0.0001), and HER-2 negativity (89% vs. 71%, p = 0.04). Clinical outcomes also favored the TC cohort, with lower rates of breast cancer-related death (1% vs. 10%; p = 0.0109) and distant metastasis (1% vs. 13%; p = 0.0028) and higher rates of 10-year overall (90% vs. 80%; p = 0.033), cause-specific (99% vs. 86%; p = 0.011), and disease-free (99% vs. 82%; p = 0.003) survival. There was a nonsignificant trend toward improved breast cancer relapse-free survival for the TC cohort (95% vs. 87%; p = 0.062) but no difference in nodal relapse-free survival or contralateral breast cancer relapse-free survival (all p values >0.05) between the cohorts. Conclusion: Our institutional experience suggests that TC, when compared with IDC, is associated with more favorable clinical-pathologic features and comparable, if not superior, outcomes after breast conservation therapy, suggesting the appropriateness of a conservative approach to this rare subtype.

  17. Long-Term Outcomes of Fractionated Stereotactic Radiation Therapy for Pituitary Adenomas at the BC Cancer Agency

    SciTech Connect (OSTI)

    Kim, Julian O.; Ma, Roy [Department of Radiation Oncology, British Columbia Cancer Agency, Vancouver (Canada); Division of Radiation Oncology and Developmental Radiotherapeutics, University of British Columbia, Vancouver (Canada); Akagami, Ryojo [Division of Neurosurgery, University of British Columbia, Vancouver (Canada); McKenzie, Michael [Department of Radiation Oncology, British Columbia Cancer Agency, Vancouver (Canada); Division of Radiation Oncology and Developmental Radiotherapeutics, University of British Columbia, Vancouver (Canada); Johnson, Michelle [Division of Endocrinology, University of British Columbia, Vancouver (Canada); Gete, Ermias [Department of Medical Physics, British Columbia Cancer Agency, Vancouver (Canada); Nichol, Alan, E-mail: anichol@bccancer.bc.ca [Department of Radiation Oncology, British Columbia Cancer Agency, Vancouver (Canada); Division of Radiation Oncology and Developmental Radiotherapeutics, University of British Columbia, Vancouver (Canada)

    2013-11-01T23:59:59.000Z

    Purpose: To assess the long-term disease control and toxicity outcomes of fractionated stereotactic radiation therapy (FSRT) in patients with pituitary adenomas treated at the BC Cancer Agency. Methods and Materials: To ensure a minimum of 5 years of clinical follow-up, this study identified a cohort of 76 patients treated consecutively with FSRT between 1998 and 2007 for pituitary adenomas: 71% (54/76) had nonfunctioning and 29% (22/76) had functioning adenomas (15 adrenocorticotrophic hormone-secreting, 5 growth hormone-secreting, and 2 prolactin-secreting). Surgery was used before FSRT in 96% (73/76) of patients. A median isocenter dose of 50.4 Gy was delivered in 28 fractions, with 100% of the planning target volume covered by the 90% isodose. Patients were followed up clinically by endocrinologists, ophthalmologists, and radiation oncologists. Serial magnetic resonance imaging was used to assess tumor response. Results: With a median follow-up time of 6.8 years (range, 0.6 - 13.1 years), the 7-year progression-free survival was 97.1% and disease-specific survival was 100%. Of the 2 patients with tumor progression, both had disease control after salvage surgery. Of the 22 patients with functioning adenomas, 50% (11/22) had complete and 9% (2/22) had partial responses after FSRT. Of the patients with normal pituitary function at baseline, 48% (14/29) experienced 1 or more hormone deficiencies after FSRT. Although 79% (60/76) of optic chiasms were at least partially within the planning target volumes, no patient experienced radiation-induced optic neuropathy. No patient experienced radionecrosis. No secondary malignancy occurred during follow-up. Conclusion: In this study of long-term follow-up of patients treated for pituitary adenomas, FSRT was safe and effective.

  18. Monitoring the Performance of an Alternative Landfill Cover at the Monticello, Utah, Uranium Mill Tailings Disposal Site

    SciTech Connect (OSTI)

    Waugh, W.J.; Kastens, M.K.; Sheader, L.R.L. [Environmental Sciences Laboratory, Grand Junction, CO (United States); Benson, C.H. [University of Wisconsin, Madison, WI (United States); Albright, W.H. [Desert Research Institute, Reno, NV (United States); Mushovic, P.S. [U.S. Environmental Protection Agency, Denver, CO (United States)

    2008-07-01T23:59:59.000Z

    The U.S. Department of Energy Office of Legacy Management (DOE) and the U.S. Environmental Protection Agency (EPA) collaborated on the design and monitoring of an alternative cover for the Monticello uranium mill tailings disposal cell, a Superfund site in southeastern Utah. Ground-water recharge is naturally limited at sites like Monticello where thick, fine-textured soils store precipitation until evaporation and plant transpiration seasonally return it to the atmosphere. The cover at Monticello uses local soils and a native plant community to mimic the natural soil water balance. The cover is fundamentally an evapotranspiration (ET) design with a capillary barrier. A 3-hectare drainage lysimeter was embedded in the cover during construction of the disposal cell in 2000. The lysimeter consists of a geo-membrane liner below the capillary barrier that directs percolation water to a monitoring system. Soil water storage is determined by integration of point water content measurements. Meteorological parameters are measured nearby. Plant cover, shrub density, and leaf area index (LAI) are monitored annually. The cover performed well over the 7-year monitoring period (2000-2007). The cumulative percolation was 4.2 mm (0.6 mm yr{sup -1}), satisfying an EPA goal of an average percolation of <3.0 mm yr{sup -1}. Almost all percolation can be attributed to the exceptionally wet winter and spring of 2004-2005 when soil water content slightly exceeded the water storage capacity of the cover. The diversity, percent cover, and LAI of vegetation increased over the monitoring period, although the density of native shrubs that extract water from deeper in the cover has remained less than revegetation targets. DOE and EPA are applying the monitoring results to plan for long-term surveillance and maintenance and to evaluate alternative cover designs for other waste disposal sites. (authors)

  19. Research and development of a high efficiency gas-fired water heater. Volume 2. Task reports

    SciTech Connect (OSTI)

    Vasilakis, A.D.; Pearson, J.F.; Gerstmann, J.

    1980-01-01T23:59:59.000Z

    Design and development of a cost-effective high efficiency gas-fired water heater to attain a service efficiency of 70% (including the effect of exfiltration) and a service efficiency of 78% (excluding exfiltration) for a 75 GPD draw at a 90/sup 0/F temperature rise, with a stored water to conditioned air temperature difference of 80/sup 0/F, are described in detail. Based on concept evaluation, a non-powered natural draft water heater was chosen as the most cost-effective design to develop. The projected installed cost is $374 compared to $200 for a conventional unit. When the project water heater is compared to a conventional unit, it has a payback of 3.7 years and life cycle savings of $350 to the consumer. A prototype water heater was designed, constructed, and tested. When operated with sealed combustion, the unit has a service efficiency of 66.4% (including the effect of exfiltration) below a burner input of 32,000 Btu/h. In the open combustion configuration, the unit operated at a measured efficiency of 66.4% Btu/h (excluding exfiltration). This compares with a service efficiency of 51.3% for a conventional water heater and 61% for a conventional high efficiency unit capable of meeting ASHRAE 90-75. Operational tests showed the unit performed well with no evidence of stacking or hot spots. It met or exceeded all capacity or usage tests specified in the program test plan and met all emission goals. Future work will concentrate on designing, building, and testing pre-production units. It is anticipated that both sealed combustion and open draft models will be pursued.

  20. Photovoltaic balance-of-system designs and costs at PVUSA

    SciTech Connect (OSTI)

    Reyes, A.B.; Jennings, C.

    1995-05-01T23:59:59.000Z

    This report is one in a series of 1994-1995 PVUSA reports that document PVUSA lessons learned at demonstration sites in California and Texas. During the last 7 years (1988 to 1994), 16 PV systems ranging from 20 kW to 500 kW have been installed. Six 20-kW emerging module technology (EMT) arrays and three turnkey (i.e., vendor designed and integrated) utility-scale systems were procured and installed at PVUSA`s main test site in Davis, California. PVUSA host utilities have installed a total of seven EMT arrays and utility-scale systems in their service areas. Additional systems at Davis and host utility sites are planned. One of PVUSA`s key objectives is to evaluate the performance, reliability, and cost of PV balance-of-system (BOS). In the procurement stage PVUSA encouraged innovative design to improve upon present practice by reducing maintenance, improving reliability, or lowering manufacturing or construction costs. The project team worked closely with suppliers during the design stage not only to ensure designs met functional and safety specifications, but to provide suggestions for improvement. This report, intended for the photovoltaic (PV) industry and for utility project managers and engineers considering PV plant construction and ownership, documents PVUSA utility-scale system design and cost lessons learned. Complementary PVUSA topical reports document: construction and safety experience; five-year assessment of EMTs; validation of the Kerman 500-kW grid-support PV plant benefits; PVUSA instrumentation and data analysis techniques; procurement, acceptance, and rating practices for PV power plants; experience with power conditioning units and power quality.