National Library of Energy BETA

Sample records for radiation induced adaptive

  1. Regulation Of Nf=kb And Mnsod In Low Dose Radiation Induced Adaptive Protection Of Mouse And Human Skin Cells

    SciTech Connect (OSTI)

    Jian Li

    2012-11-07

    A sampling of publications resulting from this grant is provided. One is on the subject of NF-κB-Mediated HER2 Overexpression in Radiation-Adaptive Resistance. Another is on NF-κB-mediated adaptive resistance to ionizing radiation.

  2. Radiation-induced bystander effect and adaptive response in mammalian cells

    E-Print Network [OSTI]

    responses at low doses of radiation and have the potential to impact the shape of the dose at low doses of radiation and have the potential to impact the shape of the doseresponse relationship, Columbia University, New York, NY 10032, USA b Radiation Effect Research Foundation, Hiroshima, Japan

  3. Adaptable radiation monitoring system and method

    DOE Patents [OSTI]

    Archer, Daniel E. (Livermore, CA); Beauchamp, Brock R. (San Ramon, CA); Mauger, G. Joseph (Livermore, CA); Nelson, Karl E. (Livermore, CA); Mercer, Michael B. (Manteca, CA); Pletcher, David C. (Sacramento, CA); Riot, Vincent J. (Berkeley, CA); Schek, James L. (Tracy, CA); Knapp, David A. (Livermore, CA)

    2006-06-20

    A portable radioactive-material detection system capable of detecting radioactive sources moving at high speeds. The system has at least one radiation detector capable of detecting gamma-radiation and coupled to an MCA capable of collecting spectral data in very small time bins of less than about 150 msec. A computer processor is connected to the MCA for determining from the spectral data if a triggering event has occurred. Spectral data is stored on a data storage device, and a power source supplies power to the detection system. Various configurations of the detection system may be adaptably arranged for various radiation detection scenarios. In a preferred embodiment, the computer processor operates as a server which receives spectral data from other networked detection systems, and communicates the collected data to a central data reporting system.

  4. Adaptive Implicit Non-Equilibrium Radiation Diffusion

    SciTech Connect (OSTI)

    Philip, Bobby [ORNL; Wang, Zhen [ORNL; Berrill, Mark A [ORNL; Rodriguez Rodriguez, Manuel [ORNL; Pernice, Michael [Idaho National Laboratory (INL)

    2013-01-01

    We describe methods for accurate and efficient long term time integra- tion of non-equilibrium radiation diffusion systems: implicit time integration for effi- cient long term time integration of stiff multiphysics systems, local control theory based step size control to minimize the required global number of time steps while control- ling accuracy, dynamic 3D adaptive mesh refinement (AMR) to minimize memory and computational costs, Jacobian Free Newton-Krylov methods on AMR grids for efficient nonlinear solution, and optimal multilevel preconditioner components that provide level independent solver convergence.

  5. Adaptive Ray Tracing for Radiative Transfer around Point Sources

    E-Print Network [OSTI]

    Tom Abel; Benjamin D. Wandelt

    2001-11-01

    We describe a novel adaptive ray tracing scheme to solve the equation of radiative transfer around point sources in hydrodynamical simulations. The angular resolution adapts to the local hydrodynamical resolution and hence is of use for adaptive meshes as well as adaptive smooth particle hydrodynamical simulations. Recursive creation of rays ensures ease of implementation. The multiple radial integrations needed to solve the time dependent radiative transfer are sped up significantly using a quad-tree once the rays are cast. Simplifications advantageous for methods with one radiation source are briefly discussed. The suggested method is easily generalized to speed up Monte Carlo radiative transfer techniques. In summary a nearly optimal use of long characteristics is presented and aspects of its implementation and comparison to other methods are given.

  6. Radiation-induced gene responses

    SciTech Connect (OSTI)

    Woloschak, G.E.; Paunesku, T.; Shearin-Jones, P.; Oryhon, J.

    1996-12-31

    In the process of identifying genes that are differentially regulated in cells exposed to ultraviolet radiation (UV), we identified a transcript that was repressed following the exposure of cells to a combination of UV and salicylate, a known inhibitor of NF-kappaB. Sequencing this band determined that it has identify to lactate dehydrogenase, and Northern blots confirmed the initial expression pattern. Analysis of the sequence of the LDH 5` region established the presence of NF-kappaB, Sp1, and two Ap-2 elements; two partial AP- 1; one partial RE, and two halves of E-UV elements were also found. Electromobility shift assays were then performed for the AP-1, NF- kappaB, and E-UV elements. These experiments revealed that binding to NF-kappaB was induced by UV but repressed with salicylic acid; UV did not affect AP-1 binding, but salicylic acid inhibited it alone or following UV exposure; and E-UV binding was repressed by UV, and salicylic acid had little effect. Since the binding of no single element correlated with the expression pattern of LDH, it is likely that multiple elements govern UV/salicylate-mediated expression.

  7. Radiation-induced mechanical property changes in filled rubber...

    Office of Scientific and Technical Information (OSTI)

    Radiation-induced mechanical property changes in filled rubber Citation Details In-Document Search Title: Radiation-induced mechanical property changes in filled rubber In a recent...

  8. Adaptive Radiations in the Context of Macroevolutionary Theory: A Paleontological Perspective

    E-Print Network [OSTI]

    Lieberman, Bruce S.

    2012-01-01

    Adaptive radiations are often invoked anytime clades show significant bursts of diversification, but it is important to not simply assume that any radiating clade constitutes an adaptive radiation. In addition, several ...

  9. Radiation-induced lung injury

    SciTech Connect (OSTI)

    Rosiello, R.A.; Merrill, W.W. )

    1990-03-01

    The use of radiation therapy is limited by the occurrence of the potentially fatal clinical syndromes of radiation pneumonitis and fibrosis. Radiation pneumonitis usually becomes clinically apparent from 2 to 6 months after completion of radiation therapy. It is characterized by fever, cough, dyspnea, and alveolar infiltrates on chest roentgenogram and may be difficult to differentiate from infection or recurrent malignancy. The pathogenesis is uncertain, but appears to involve both direct lung tissue toxicity and an inflammatory response. The syndrome may resolve spontaneously or may progress to respiratory failure. Corticosteroids may be effective therapy if started early in the course of the disease. The time course for the development of radiation fibrosis is later than that for radiation pneumonitis. It is usually present by 1 year following irradiation, but may not become clinically apparent until 2 years after radiation therapy. It is characterized by the insidious onset of dyspnea on exertion. It most often is mild, but can progress to chronic respiratory failure. There is no known successful treatment for this condition. 51 references.

  10. Ultraviolet radiation induced discharge laser

    DOE Patents [OSTI]

    Gilson, Verle A. (Livermore, CA); Schriever, Richard L. (Livermore, CA); Shearer, James W. (Livermore, CA)

    1978-01-01

    An ultraviolet radiation source associated with a suitable cathode-anode electrode structure, disposed in a gas-filled cavity of a high pressure pulsed laser, such as a transverse electric atmosphere (TEA) laser, to achieve free electron production in the gas by photoelectric interaction between ultraviolet radiation and the cathode prior to the gas-exciting cathode-to-anode electrical discharge, thereby providing volume ionization of the gas. The ultraviolet radiation is produced by a light source or by a spark discharge.

  11. Adapting Induced Pluripotent Stem Cells For Clinical Use

    E-Print Network [OSTI]

    Brutlag, Doug

    ://www.nature.com/nbt/journal/v27/n5/full/nbt.1535.html Kim, D. et al. Generation of human induced pluripotent stem cellsAdapting Induced Pluripotent Stem Cells For Clinical Use Dana Wyman Professor Brutlag Genomics Pluripotent Stem Cells 7 days hES medium +MEF #12;Immunofluorescence Test ES Cells (+ control) Untransduced

  12. Genomics and vertebrate adaptive radiation: a celebration of the first cichlid genome

    E-Print Network [OSTI]

    Renn, Susan C.P.

    Genomics and vertebrate adaptive radiation: a celebration of the first cichlid genome C. Darrin ``Genomics and Vertebrate Adaptive Radiation: A Celebration of the First Cichlid Genome'' was held the central topic was the genomics of adaptive radiation in cichlid fishes, the symposium integrated speakers

  13. Adaptive Radiation and Ecological Opportunity in Sulawesi and Philippine Fanged Frog (Limnonectes) Communities.

    E-Print Network [OSTI]

    McGuire, Jimmy A.

    Adaptive Radiation and Ecological Opportunity in Sulawesi and Philippine Fanged Frog (Limnonectes the american naturalist august 2011 Adaptive Radiation and Ecological Opportunity in Sulawesi and Philippine on Sulawesi Island is lower than it is in the Philippines, but Sulawesi supports a sur- prising diversity

  14. 17 August 2000 FEL 2000 1 Radiation Induced by Relativistic

    E-Print Network [OSTI]

    17 August 2000 FEL 2000 1 Radiation Induced by Relativistic Beams Passing Over a Diffraction 2000 FEL 2000 2 Outline Spontaneous Smith-Purcell radiation (SPR) can be intense. Data from the ATF. #12;17 August 2000 FEL 2000 3 Smith-Purcell radiation q v b Dispersion relation: l n c vl cos 1 cosn

  15. Localized acne induced by radiation therapy

    E-Print Network [OSTI]

    Hubiche, T; Sibaud, V

    2014-01-01

    total dose, radiation dose to the skin, fractionation timing, type of beam, treated volume, and irradiation

  16. Computer-aided detection of radiation-induced cerebral microbleeds on susceptibility-weighted MR images

    E-Print Network [OSTI]

    2013-01-01

    ynicl Computer-aided detection of radiation-induced cerebraladvantageous for the detection of radiation-induced CMBs,radiation-induced CMBs with low contrast is a further factor that complicates their detection.

  17. Block-structured Adaptive Finite Volume Methods for Shock-Induced Combustion

    E-Print Network [OSTI]

    Deiterding, Ralf

    Block-structured Adaptive Finite Volume Methods for Shock-Induced Combustion Simulation Ralf-Induced Combustion Simulation 1 #12;Structure of the lectures Block-structured Adaptive Finite Volume Methods for Shock-Induced Combustion Simulation 2 #12;Structure of the lectures 1. Fundamentals of finite volume

  18. American Journal of Botany 84(9): 12361246. 1997. GENETICS OF ADAPTIVE RADIATION IN HAWAIIAN AND

    E-Print Network [OSTI]

    Whitkus, Richard

    with adaptive radiation in the genus. Levels of RFLP diversity are greater than those reported for isozymes, yet-9204261 to RW and DEB-9200578 to TKL and the UC Riverside Agricultural Experimental Station funds to RW. 4

  19. Light Induced Superconductivity | Stanford Synchrotron Radiation...

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

    Light Induced Superconductivity Wednesday, August 5, 2015 - 3:00pm SLAC, Redtail Hawk Conference Room 108A Speaker: Daniele Nicoletti, Max Planck Institute for the Structure and...

  20. Mitigation of radiation induced surface contamination

    DOE Patents [OSTI]

    Klebanoff, Leonard E. (Dublin, CA); Stulen, Richard H. (Livermore, CA)

    2003-01-01

    A process for mitigating or eliminating contamination and/or degradation of surfaces having common, adventitious atmospheric contaminants adsorbed thereon and exposed to radiation. A gas or a mixture of gases is introduced into the environment of a surface(s) to be protected. The choice of the gaseous species to be introduced (typically a hydrocarbon gas, water vapor, or oxygen or mixtures thereof) is dependent upon the contaminant as well as the ability of the gaseous species to bind to the surface to be protected. When the surface and associated bound species are exposed to radiation reactive species are formed that react with surface contaminants such as carbon or oxide films to form volatile products (e.g., CO, CO.sub.2) which desorb from the surface.

  1. Simulation of radiation-induced defects

    E-Print Network [OSTI]

    Peltola, Timo

    2015-01-01

    Mainly due to their outstanding performance the position sensitive silicon detectors are widely used in the tracking systems of High Energy Physics experiments such as the ALICE, ATLAS, CMS and LHCb at LHC, the world's largest particle physics accelerator at CERN, Geneva. The foreseen upgrade of the LHC to its high luminosity (HL) phase (HL-LHC scheduled for 2023), will enable the use of maximal physics potential of the facility. After 10 years of operation the expected fluence will expose the tracking systems at HL-LHC to a radiation environment that is beyond the capacity of the present system design. Thus, for the required upgrade of the all-silicon central trackers extensive measurements and simulation studies for silicon sensors of different designs and materials with sufficient radiation tolerance have been initiated within the RD50 Collaboration. Supplementing measurements, simulations are in vital role for e.g. device structure optimization or predicting the electric fields and trapping in the silicon...

  2. Mechanisms of radiation-induced neoplastic cell transformation

    SciTech Connect (OSTI)

    Yang, T.C.H.; Tobias, C.A.

    1984-04-01

    Studies with cultured mammalian cells demonstrated clearly that radiation can transform cells directly and can enhance the cell transformation by oncogenic DNA viruses. In general, high-LET heavy-ion radiation can be more effective than X and gamma rays in inducing neoplastic cell transformation. Various experimental results indicate that radiation-induced DNA damage, most likely double-strand breaks, is important for both the initiation of cell transformation and for the enhancement of viral transformation. Some of the transformation and enhancement lesions can be repaired properly in the cell, and the amount of irrepairable lesions produced by a given dose depends on the quality of radiation. An inhibition of repair processes with chemical agents can increase the transformation frequency of cells exposed to radiation and/or oncogenic viruses, suggesting that repair mechanisms may play an important role in the radiation transformation. The progression of radiation-transformed cells appears to be a long and complicated process that can be modulated by some nonmutagenic chemical agents, e.g., DMSO. Normal cells can inhibit the expression of transforming properties of tumorigenic cells through an as yet unknown mechanism. The progression and expression of transformation may involve some epigenetic changes in the irradiated cells. 38 references, 15 figures, 1 table.

  3. Simulation of radiation-induced defects

    E-Print Network [OSTI]

    Timo Peltola

    2015-09-29

    Mainly due to their outstanding performance the position sensitive silicon detectors are widely used in the tracking systems of High Energy Physics experiments such as the ALICE, ATLAS, CMS and LHCb at LHC, the world's largest particle physics accelerator at CERN, Geneva. The foreseen upgrade of the LHC to its high luminosity (HL) phase (HL-LHC scheduled for 2023), will enable the use of maximal physics potential of the facility. After 10 years of operation the expected fluence will expose the tracking systems at HL-LHC to a radiation environment that is beyond the capacity of the present system design. Thus, for the required upgrade of the all-silicon central trackers extensive measurements and simulation studies for silicon sensors of different designs and materials with sufficient radiation tolerance have been initiated within the RD50 Collaboration. Supplementing measurements, simulations are in vital role for e.g. device structure optimization or predicting the electric fields and trapping in the silicon sensors. The main objective of the device simulations in the RD50 Collaboration is to develop an approach to model and predict the performance of the irradiated silicon detectors using professional software. The first successfully developed quantitative models for radiation damage, based on two effective midgap levels, are able to reproduce the experimentally observed detector characteristics like leakage current, full depletion voltage and charge collection efficiency (CCE). Recent implementations of additional traps at the SiO$_2$/Si interface or close to it have expanded the scope of the experimentally agreeing simulations to such surface properties as the interstrip resistance and capacitance, and the position dependency of CCE for strip sensors irradiated up to $\\sim$$1.5\\times10^{15}$ n$_{\\textrm{eq}}\\textrm{cm}^{-2}$.

  4. Radiation-induced decomposition of explosives under extreme conditions

    SciTech Connect (OSTI)

    Giefers, Hubertus; Pravica, Michael; Yang, Wenge; Liermann, Peter

    2008-11-03

    We present high-pressure and high temperature studies of the synchrotron radiation-induced decomposition of powder secondary high explosives pentaerythritol tetranitrate (PETN) and 1,3,5-triamino-2,4,6-trinitrobenzene (TATB) using white beam synchrotron radiation at the 16 BM-B and 16 BM-D sectors of the HP-CAT beamline at the Advanced Photon Source. The radiation-induced decomposition rate TATB showed dramatic slowing with pressure up to 26.6 GPa (the highest pressure studied), implying a positive activation volume of the activated complex. The decomposition rate of PETN varied little with pressure up to 15.7 GPa (the highest pressure studied). Diffraction line intensities were measured as a function of time using energy-dispersive methods. By measuring the decomposition rate as a function of pressure and temperature, kinetic and other constants associated with the decomposition reactions were extracted.

  5. Mechanisms of radiation-induced gene responses

    SciTech Connect (OSTI)

    Woloschak, G.E.; Paunesku, T.

    1996-10-01

    In the process of identifying genes differentially expressed in cells exposed ultraviolet radiation, we have identified a transcript having a 26-bp region that is highly conserved in a variety of species including Bacillus circulans, yeast, pumpkin, Drosophila, mouse, and man. When the 5` region (flanking region or UTR) of a gene, the sequence is predominantly in +/+ orientation with respect to the coding DNA strand; while in the coding region and the 3` region (UTR), the sequence is most frequently in the +/-orientation with respect to the coding DNA strand. In two genes, the element is split into two parts; however, in most cases, it is found only once but with a minimum of 11 consecutive nucleotides precisely depicting the original sequence. The element is found in a large number of different genes with diverse functions (from human ras p21 to B. circulans chitonase). Gel shift assays demonstrated the presence of a protein in HeLa cell extracts that binds to the sense and antisense single-stranded consensus oligomers, as well as to the double- stranded oligonucleotide. When double-stranded oligomer was used, the size shift demonstrated as additional protein-oligomer complex larger than the one bound to either sense or antisense single-stranded consensus oligomers alone. It is speculated either that this element binds to protein(s) important in maintaining DNA is a single-stranded orientation for transcription or, alternatively that this element is important in the transcription-coupled DNA repair process.

  6. Copyright 1998 by the Genetics Society of America Genetics of Adaptive Radiation in Hawaiian and Cook Islands Species of

    E-Print Network [OSTI]

    Whitkus, Richard

    Copyright 1998 by the Genetics Society of America Genetics of Adaptive Radiation in Hawaiian and Cook Islands Species of Tetramolopium (Asteraceae). II. Genetic Linkage Map and Its Implications, 1998 ABSTRACT In a study of the genetic mechanisms associated with adaptive radiation in Hawaiian

  7. Adaptive Linear Prediction of Radiation Belt Electrons Using the Kalman Filter

    E-Print Network [OSTI]

    to changes in solar wind bulk speed using linear prediction filters [Baker et al., 1990; Vassiliadis et alAdaptive Linear Prediction of Radiation Belt Electrons Using the Kalman Filter E.J. Rigler, D improvement in zero-time-lag electron log-flux "predictions" relative to models that are based on time

  8. Convergent evolution of behavior in an adaptive radiation of Hawaiian web-building spiders

    E-Print Network [OSTI]

    Blackledge, Todd

    Convergent evolution of behavior in an adaptive radiation of Hawaiian web-building spiders Todd A independently evolve webs with similar architectures. Tetragnatha spiders are the only nocturnal orb- weaving-occur within mesic and wet forest habitats on each of the main islands. Therefore, comparison of web

  9. Modeling radiation-induced mixing at interfaces between low solubility metals

    E-Print Network [OSTI]

    Zhang, Liang, Ph. D. Massachusetts Institute of Technology

    2014-01-01

    This thesis studies radiation-induced mixing at interfaces between low solubility metals using molecular dynamics (MD) computer simulations. It provides original contributions on the fundamental mechanisms of radiation-induced ...

  10. Radiation-Induced Notch Signaling in Breast Cancer Stem Cells

    SciTech Connect (OSTI)

    Lagadec, Chann; Vlashi, Erina; Alhiyari, Yazeed; Phillips, Tiffany M.; Bochkur Dratver, Milana; Pajonk, Frank

    2013-11-01

    Purpose: To explore patterns of Notch receptor and ligand expression in response to radiation that could be crucial in defining optimal dosing schemes for ?-secretase inhibitors if combined with radiation. Methods and Materials: Using MCF-7 and T47D breast cancer cell lines, we used real-time reverse transcriptionpolymerase chain reaction to study the Notch pathway in response to radiation. Results: We show that Notch receptor and ligand expression during the first 48 hours after irradiation followed a complex radiation dosedependent pattern and was most pronounced in mammospheres, enriched for breast cancer stem cells. Additionally, radiation activated the Notch pathway. Treatment with a ?-secretase inhibitor prevented radiation-induced Notch family gene expression and led to a significant reduction in the size of the breast cancer stem cell pool. Conclusions: Our results indicate that, if combined with radiation, ?-secretase inhibitors may prevent up-regulation of Notch receptor and ligand family members and thus reduce the number of surviving breast cancer stem cells.

  11. Nature of Radiation-Induced Defects in Quartz

    E-Print Network [OSTI]

    Bu Wang; Yingtian Yu; Isabella Pignatelli; Gaurav N. Sant; Mathieu Bauchy

    2015-04-10

    Although quartz ($\\rm \\alpha$-form) is a mineral used in numerous applications wherein radiation exposure is an issue, the nature of the atomistic defects formed during radiation-induced damage have not been fully clarified. Especially, the extent of oxygen vacancy formation is still debated, which is an issue of primary importance as optical techniques based on charged oxygen vacancies have been utilized to assess the level of radiation damage in quartz. In this paper, molecular dynamics (MD) simulations are applied to study the effects of ballistic impacts on the atomic network of quartz. We show that the defects that are formed mainly consist of over-coordinated Si and O, as well as Si--O connectivity defects, e.g., small Si--O rings and edge-sharing Si tetrahedra. Oxygen vacancies, on the contrary, are found in relatively low abundance, suggesting that characterizations based on $E^{\\prime}$ centers do not adequately capture radiation-induced structural damage in quartz. Finally, we evaluate the dependence on the incident energy, of the amount of each type of the point defects formed, and quantify unambiguously the threshold displacement energies for both O and Si atoms. These results provide a comprehensive basis to assess the nature and extent of radiation damage in quartz.

  12. Oxidative Stress Mediates Radiation Lung Injury by Inducing Apoptosis

    SciTech Connect (OSTI)

    Zhang Yu; Zhang Xiuwu; Rabbani, Zahid N. [Department of Radiation Oncology, Duke University Medical Center, Durham, NC (United States); Jackson, Isabel L. [Department of Pathology, Duke University Medical Center, Durham, NC (United States); Vujaskovic, Zeljko, E-mail: vujas@radonc.duke.edu [Department of Radiation Oncology, Duke University Medical Center, Durham, NC (United States); Department of Pathology, Duke University Medical Center, Durham, NC (United States)

    2012-06-01

    Purpose: Apoptosis in irradiated normal lung tissue has been observed several weeks after radiation. However, the signaling pathway propagating cell death after radiation remains unknown. Methods and Materials: C57BL/6J mice were irradiated with 15 Gy to the whole thorax. Pro-apoptotic signaling was evaluated 6 weeks after radiation with or without administration of AEOL10150, a potent catalytic scavenger of reactive oxygen and nitrogen species. Results: Apoptosis was observed primarily in type I and type II pneumocytes and endothelium. Apoptosis correlated with increased PTEN expression, inhibition of downstream PI3K/AKT signaling, and increased p53 and Bax protein levels. Transforming growth factor-{beta}1, Nox4, and oxidative stress were also increased 6 weeks after radiation. Therapeutic administration of AEOL10150 suppressed pro-apoptotic signaling and dramatically reduced the number of apoptotic cells. Conclusion: Increased PTEN signaling after radiation results in apoptosis of lung parenchymal cells. We hypothesize that upregulation of PTEN is influenced by Nox4-derived oxidative stress. To our knowledge, this is the first study to highlight the role of PTEN in radiation-induced pulmonary toxicity.

  13. Radiation-induced decomposition of PETN and TATB under pressure

    SciTech Connect (OSTI)

    Giefers, Hubertus; Pravica, Michael; Liermann, Hanns-Peter; Yang, Wenge

    2008-10-02

    We have investigated decomposition of PETN and TATB induced by white synchrotron X-ray radiation in a diamond anvil cell at ambient temperature and two pressures, nearly ambient and about 6 GPa. The decomposition rate of TATB decreases significantly when it is pressurized to 5.9 GPa. The measurements were highly reproducible and allowed us to obtain decomposition rates and the order parameters of the reactions.

  14. A general hybrid radiation transport scheme for star formation simulations on an adaptive grid

    SciTech Connect (OSTI)

    Klassen, Mikhail; Pudritz, Ralph E. [Department of Physics and Astronomy, McMaster University 1280 Main Street W, Hamilton, ON L8S 4M1 (Canada); Kuiper, Rolf [Max Planck Institute for Astronomy Knigstuhl 17, D-69117 Heidelberg (Germany); Peters, Thomas [Institut fr Computergesttzte Wissenschaften, Universitt Zrich Winterthurerstrasse 190, CH-8057 Zrich (Switzerland); Banerjee, Robi; Buntemeyer, Lars, E-mail: klassm@mcmaster.ca [Hamburger Sternwarte, Universitt Hamburg Gojenbergsweg 112, D-21029 Hamburg (Germany)

    2014-12-10

    Radiation feedback plays a crucial role in the process of star formation. In order to simulate the thermodynamic evolution of disks, filaments, and the molecular gas surrounding clusters of young stars, we require an efficient and accurate method for solving the radiation transfer problem. We describe the implementation of a hybrid radiation transport scheme in the adaptive grid-based FLASH general magnetohydrodyanmics code. The hybrid scheme splits the radiative transport problem into a raytracing step and a diffusion step. The raytracer captures the first absorption event, as stars irradiate their environments, while the evolution of the diffuse component of the radiation field is handled by a flux-limited diffusion solver. We demonstrate the accuracy of our method through a variety of benchmark tests including the irradiation of a static disk, subcritical and supercritical radiative shocks, and thermal energy equilibration. We also demonstrate the capability of our method for casting shadows and calculating gas and dust temperatures in the presence of multiple stellar sources. Our method enables radiation-hydrodynamic studies of young stellar objects, protostellar disks, and clustered star formation in magnetized, filamentary environments.

  15. Cerenkov emission induced by external beam radiation stimulates molecular fluorescence

    SciTech Connect (OSTI)

    Axelsson, Johan; Davis, Scott C.; Gladstone, David J.; Pogue, Brian W.

    2011-07-15

    Purpose: Cerenkov emission is induced when a charged particle moves faster than the speed of light in a given medium. Both x-ray photons and electrons produce optical Cerenkov photons in everyday radiation therapy of tissue; yet, this phenomenon has never been fully documented. This study quantifies the emissions and also demonstrates that the Cerenkov emission can excite a fluorophore, protoporphyrin IX (PpIX), embedded in biological phantoms. Methods: In this study, Cerenkov emission induced by radiation from a clinical linear accelerator is investigated. Biological mimicking phantoms were irradiated with x-ray photons, with energies of 6 or 18 MV, or electrons at energies 6, 9, 12, 15, or 18 MeV. The Cerenkov emission and the induced molecular fluorescence were detected by a camera or a spectrometer equipped with a fiber optic cable. Results: It is shown that both x-ray photons and electrons, at MeV energies, produce optical Cerenkov photons in tissue mimicking media. Furthermore, we demonstrate that the Cerenkov emission can excite a fluorophore, protoporphyrin IX (PpIX), embedded in biological phantoms. Conclusions: The results here indicate that molecular fluorescence monitoring during external beam radiotherapy is possible.

  16. DNA damage in cells exhibiting radiation-induced genomic instability

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

    Keszenman, Deborah J.; Kolodiuk, Lucia; Baulch, Janet E.

    2015-02-22

    Cells exhibiting radiation induced genomic instability exhibit varied spectra of genetic and chromosomal aberrations. Even so, oxidative stress remains a common theme in the initiation and/or perpetuation of this phenomenon. Isolated oxidatively modified bases, abasic sites, DNA single strand breaks and clustered DNA damage are induced in normal mammalian cultured cells and tissues due to endogenous reactive oxygen species generated during normal cellular metabolism in an aerobic environment. While sparse DNA damage may be easily repaired, clustered DNA damage may lead to persistent cytotoxic or mutagenic events that can lead to genomic instability. In this study, we tested the hypothesismorethat DNA damage signatures characterised by altered levels of endogenous, potentially mutagenic, types of DNA damage and chromosomal breakage are related to radiation-induced genomic instability and persistent oxidative stress phenotypes observed in the chromosomally unstable progeny of irradiated cells. The measurement of oxypurine, oxypyrimidine and abasic site endogenous DNA damage showed differences in non-double-strand breaks (DSB) clusters among the three of the four unstable clones evaluated as compared to genomically stable clones and the parental cell line. These three unstable clones also had increased levels of DSB clusters. The results of this study demonstrate that each unstable cell line has a unique spectrum of persistent damage and lead us to speculate that alterations in DNA damage signaling and repair may be related to the perpetuation of genomic instability.less

  17. Poster Session 08: Bystander and other Low Dose Effect Exogenous carbon monoxide suppresses adaptive response induced

    E-Print Network [OSTI]

    Yu, Peter K.N.

    Poster Session 08: Bystander and other Low Dose Effect Exogenous carbon monoxide suppresses; adaptive response; zebrafish embryos Journal of Radiation Research, 2014, 55, i115 Supplement doi: 10 prepared medium with the chemical at different time points after the application of the priming dose. Our

  18. Simulating and Detecting Radiation-Induced Errors for Onboard Machine Learning

    E-Print Network [OSTI]

    Simulating and Detecting Radiation-Induced Errors for Onboard Machine Learning Robert Granat, Kiri-based fault tolerance (ABFT) methods into onboard data analysis algorithms to detect radiation-induced errors for detecting and recovering from such errors. A common hardware technique for achieving radiation protection

  19. Measurements of prompt radiation induced conductivity in Teflon (PTFE).

    SciTech Connect (OSTI)

    Hartman, E. Frederick; Zarick, Thomas Andrew; Sheridan, Timothy J.; Preston, E.

    2013-05-01

    We performed measurements of the prompt radiation induced conductivity (RIC) in thin samples of Teflon (PTFE) at the Little Mountain Medusa LINAC facility in Ogden, UT. Three mil (76.2 microns) samples were irradiated with a 0.5 %CE%BCs pulse of 20 MeV electrons, yielding dose rates of 1E9 to 1E11 rad/s. We applied variable potentials up to 2 kV across the samples and measured the prompt conduction current. Details of the experimental apparatus and analysis are reported in this report on prompt RIC in Teflon.

  20. Measurements of prompt radiation induced conductivity of Kapton.

    SciTech Connect (OSTI)

    Preston, Eric F.; Zarick, Thomas Andrew; Sheridan, Timothy J.; Hartman, E. Frederick; Stringer, Thomas Arthur

    2010-10-01

    We performed measurements of the prompt radiation induced conductivity in thin samples of Kapton (polyimide) at the Little Mountain Medusa LINAC facility in Ogden, UT. Three mil samples were irradiated with a 0.5 {mu}s pulse of 20 MeV electrons, yielding dose rates of 1E9 to 1E10 rad/s. We applied variable potentials up to 2 kV across the samples and measured the prompt conduction current. Analysis rendered prompt conductivity coefficients between 6E-17 and 2E-16 mhos/m per rad/s, depending on the dose rate and the pulse width.

  1. Spatially adaptive radiation-hydrodynamical simulations of galaxy formation during cosmological reionization

    E-Print Network [OSTI]

    Pawlik, Andreas H; Vecchia, Claudio Dalla

    2015-01-01

    We present a suite of cosmological radiation-hydrodynamical simulations of the assembly of galaxies driving the reionization of the intergalactic medium (IGM) at z >~ 6. The simulations account for the hydrodynamical feedback from photoionization heating and the explosion of massive stars as supernovae (SNe). Our reference simulation, which was carried out in a box of size 25 comoving Mpc/h using 2 x 512^3 particles, produces a reasonable reionization history and matches the observed UV luminosity function of galaxies. Simulations with different box sizes and resolutions are used to investigate numerical convergence, and simulations in which either SNe or photoionization heating or both are turned off, are used to investigate the role of feedback from star formation. Ionizing radiation is treated using accurate radiative transfer at the high spatially adaptive resolution at which the hydrodynamics is carried out. SN feedback strongly reduces the star formation rates (SFRs) over nearly the full mass range of s...

  2. A parallel adaptive method for simulating shock-induced combustion with detailed

    E-Print Network [OSTI]

    Deiterding, Ralf

    A parallel adaptive method for simulating shock-induced combustion with detailed chemical kinetics combustion phenomena in gases, particularly detonation waves. The method uses a Cartesian mesh, that are characteristic for accident scenarios. Innovative technical applications of gaseous detonations include pulsed

  3. Poster Session 08: Bystander and other Low Dose Effect Roles of nitric oxide in adaptive response induced in zebrafish

    E-Print Network [OSTI]

    Yu, Peter K.N.

    Poster Session 08: Bystander and other Low Dose Effect Roles of nitric oxide in adaptive response Radiat Res 2013;54:73647. Journal of Radiation Research, 2014, 55, i114 Supplement doi: 10.1093/jrr/rrt161 The Author 2014. Published by Oxford University Press on behalf of The Japan Radiation Research

  4. Dosimetric Analysis of Radiation-induced Gastric Bleeding

    SciTech Connect (OSTI)

    Feng, Mary, E-mail: maryfeng@umich.edu [Department of Radiation Oncology, University of Michigan School of Medicine, Ann Arbor, Michigan (United States)] [Department of Radiation Oncology, University of Michigan School of Medicine, Ann Arbor, Michigan (United States); Normolle, Daniel [Department of Biostatistics, University of Pittsburgh, Pittsburgh, Pennsylvania (United States)] [Department of Biostatistics, University of Pittsburgh, Pittsburgh, Pennsylvania (United States); Pan, Charlie C. [Department of Radiation Oncology, University of Michigan School of Medicine, Ann Arbor, Michigan (United States)] [Department of Radiation Oncology, University of Michigan School of Medicine, Ann Arbor, Michigan (United States); Dawson, Laura A. [Department of Radiation Oncology, Princess Margaret Hospital, University of Toronto, Toronto, Ontario (Canada)] [Department of Radiation Oncology, Princess Margaret Hospital, University of Toronto, Toronto, Ontario (Canada); Amarnath, Sudha [Department of Radiation Oncology, University of Michigan School of Medicine, Ann Arbor, Michigan (United States)] [Department of Radiation Oncology, University of Michigan School of Medicine, Ann Arbor, Michigan (United States); Ensminger, William D. [Department of Internal Medicine, Division of Hematology Oncology, University of Michigan School of Medicine, Ann Arbor, Michigan (United States)] [Department of Internal Medicine, Division of Hematology Oncology, University of Michigan School of Medicine, Ann Arbor, Michigan (United States); Lawrence, Theodore S.; Ten Haken, Randall K. [Department of Radiation Oncology, University of Michigan School of Medicine, Ann Arbor, Michigan (United States)] [Department of Radiation Oncology, University of Michigan School of Medicine, Ann Arbor, Michigan (United States)

    2012-09-01

    Purpose: Radiation-induced gastric bleeding has been poorly understood. In this study, we described dosimetric predictors for gastric bleeding after fractionated radiation therapy. Methods and Materials: The records of 139 sequential patients treated with 3-dimensional conformal radiation therapy (3D-CRT) for intrahepatic malignancies were reviewed. Median follow-up was 7.4 months. The parameters of a Lyman normal tissue complication probability (NTCP) model for the occurrence of {>=}grade 3 gastric bleed, adjusted for cirrhosis, were fitted to the data. The principle of maximum likelihood was used to estimate parameters for NTCP models. Results: Sixteen of 116 evaluable patients (14%) developed gastric bleeds at a median time of 4.0 months (mean, 6.5 months; range, 2.1-28.3 months) following completion of RT. The median and mean maximum doses to the stomach were 61 and 63 Gy (range, 46-86 Gy), respectively, after biocorrection of each part of the 3D dose distributions to equivalent 2-Gy daily fractions. The Lyman NTCP model with parameters adjusted for cirrhosis predicted gastric bleed. Best-fit Lyman NTCP model parameters were n=0.10 and m=0.21 and with TD{sub 50} (normal) = 56 Gy and TD{sub 50} (cirrhosis) = 22 Gy. The low n value is consistent with the importance of maximum dose; a lower TD{sub 50} value for the cirrhosis patients points out their greater sensitivity. Conclusions: This study demonstrates that the Lyman NTCP model has utility for predicting gastric bleeding and that the presence of cirrhosis greatly increases this risk. These findings should facilitate the design of future clinical trials involving high-dose upper abdominal radiation.

  5. Adaptive Breast Radiation Therapy Using Modeling of Tissue Mechanics: A Breast Tissue Segmentation Study

    SciTech Connect (OSTI)

    Juneja, Prabhjot; Harris, Emma J.; Kirby, Anna M.; Evans, Philip M.

    2012-11-01

    Purpose: To validate and compare the accuracy of breast tissue segmentation methods applied to computed tomography (CT) scans used for radiation therapy planning and to study the effect of tissue distribution on the segmentation accuracy for the purpose of developing models for use in adaptive breast radiation therapy. Methods and Materials: Twenty-four patients receiving postlumpectomy radiation therapy for breast cancer underwent CT imaging in prone and supine positions. The whole-breast clinical target volume was outlined. Clinical target volumes were segmented into fibroglandular and fatty tissue using the following algorithms: physical density thresholding; interactive thresholding; fuzzy c-means with 3 classes (FCM3) and 4 classes (FCM4); and k-means. The segmentation algorithms were evaluated in 2 stages: first, an approach based on the assumption that the breast composition should be the same in both prone and supine position; and second, comparison of segmentation with tissue outlines from 3 experts using the Dice similarity coefficient (DSC). Breast datasets were grouped into nonsparse and sparse fibroglandular tissue distributions according to expert assessment and used to assess the accuracy of the segmentation methods and the agreement between experts. Results: Prone and supine breast composition analysis showed differences between the methods. Validation against expert outlines found significant differences (P<.001) between FCM3 and FCM4. Fuzzy c-means with 3 classes generated segmentation results (mean DSC = 0.70) closest to the experts' outlines. There was good agreement (mean DSC = 0.85) among experts for breast tissue outlining. Segmentation accuracy and expert agreement was significantly higher (P<.005) in the nonsparse group than in the sparse group. Conclusions: The FCM3 gave the most accurate segmentation of breast tissues on CT data and could therefore be used in adaptive radiation therapy-based on tissue modeling. Breast tissue segmentation methods should be used with caution in patients with sparse fibroglandular tissue distribution.

  6. Measurements of prompt radiation induced conductivity of alumina and sapphire.

    SciTech Connect (OSTI)

    Hartman, E. Frederick; Zarick, Thomas Andrew; Sheridan, Timothy J.; Preston, Eric F.

    2011-04-01

    We performed measurements of the prompt radiation induced conductivity in thin samples of Alumina and Sapphire at the Little Mountain Medusa LINAC facility in Ogden, UT. Five mil thick samples were irradiated with pulses of 20 MeV electrons, yielding dose rates of 1E7 to 1E9 rad/s. We applied variable potentials up to 1 kV across the samples and measured the prompt conduction current. Analysis rendered prompt conductivity coefficients between 1E10 and 1E9 mho/m/(rad/s), depending on the dose rate and the pulse width for Alumina and 1E7 to 6E7 mho/m/(rad/s) for Sapphire.

  7. Radiation induced effects on mechanical properties of nanoporous gold foams

    SciTech Connect (OSTI)

    Caro, M., E-mail: magda@lanl.gov, E-mail: efu@pku.edu.cn; Fu, E. G., E-mail: magda@lanl.gov, E-mail: efu@pku.edu.cn; Wang, Y. Q.; Martinez, E.; Caro, A. [Materials Science and Technology Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Mook, W. M.; Sheehan, C.; Baldwin, J. K. [Center for Integrated Nanotechnology, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)

    2014-06-09

    It has recently been shown that due to a high surface-to-volume ratio, nanoporous materials display radiation tolerance. The abundance of surfaces, which are perfect sinks for defects, and the relation between ligament size, defect diffusion, and time combine to define a window of radiation resistance [Fu et al., Appl. Phys. Lett. 101, 191607 (2012)]. Outside this window, the dominant defect created by irradiation in Au nanofoams are stacking fault tetrahedra (SFT). Molecular dynamics computer simulations of nanopillars, taken as the elemental constituent of foams, predict that SFTs act as dislocation sources inducing softening, in contrast to the usual behavior in bulk materials, where defects are obstacles to dislocation motion, producing hardening. In this work we test that prediction and answer the question whether irradiation actually hardens or softens a nanofam. Ne ion irradiations of gold nanofoams were performed at room temperature for a total dose up to 4 dpa, and their mechanical behavior was measured by nanoindentation. We find that hardness increases after irradiation, a result that we analyze in terms of the role of SFTs on the deformation mode of foams.

  8. Simultaneous radiation pressure induced heating and cooling of an opto-mechanical resonator

    E-Print Network [OSTI]

    Afshari, Ehsan

    Simultaneous radiation pressure induced heating and cooling of an opto- mechanical resonator://apl.aip.org/about/rights_and_permissions #12;Simultaneous radiation pressure induced heating and cooling of an opto-mechanical resonator to a combination of large mechanical oscillations and necessary saturation of amplification, the noise floor

  9. Radiation induced leakage current and stress induced leakage current in ultra-thin gate oxides

    SciTech Connect (OSTI)

    Ceschia, M.; Paccagnella, A.; Cester, A.; Scarpa, A.; Ghidini, G.

    1998-12-01

    Low-field leakage current has been measured in thin oxides after exposure to ionizing radiation. This Radiation Induced Leakage Current (RILC) can be described as an inelastic tunneling process mediated by neutral traps in the oxide, with an energy loss of about 1 eV. The neutral trap distribution is influenced by the oxide field applied during irradiation, thus indicating that the precursors of the neutral defects are charged, likely being defects associated to trapped holes. The maximum leakage current is found under zero-field condition during irradiation, and it rapidly decreases as the field is enhanced, due to a displacement of the defect distribution across the oxide towards the cathodic interface. The RILC kinetics are linear with the cumulative dose, in contrast with the power law found on electrically stressed devices.

  10. EXTRAPOLATING RADIATION-INDUCED CANCER RISKS FROM LOW DOSES TO VERY LOW DOSES

    E-Print Network [OSTI]

    Brenner, David Jonathan

    Paper EXTRAPOLATING RADIATION-INDUCED CANCER RISKS FROM LOW DOSES TO VERY LOW DOSES David J are increased at low doses ( 10 mGy). Discussed here are the issues related to extrapolating radiation risks from low radiation doses to very low doses (

  11. Dynamic implicit 3D adaptive mesh refinement for non-equilibrium radiation diffusion

    SciTech Connect (OSTI)

    B. Philip; Z. Wang; M.A. Berrill; M. Birke; M. Pernice

    2014-04-01

    The time dependent non-equilibrium radiation diffusion equations are important for solving the transport of energy through radiation in optically thick regimes and find applications in several fields including astrophysics and inertial confinement fusion. The associated initial boundary value problems that are encountered often exhibit a wide range of scales in space and time and are extremely challenging to solve. To efficiently and accurately simulate these systems we describe our research on combining techniques that will also find use more broadly for long term time integration of nonlinear multi-physics systems: implicit time integration for efficient long term time integration of stiff multi-physics systems, local control theory based step size control to minimize the required global number of time steps while controlling accuracy, dynamic 3D adaptive mesh refinement (AMR) to minimize memory and computational costs, Jacobian Free NewtonKrylov methods on AMR grids for efficient nonlinear solution, and optimal multilevel preconditioner components that provide level independent solver convergence.

  12. Irradiated Esophageal Cells are Protected from Radiation-Induced Recombination by MnSOD Gene Therapy

    E-Print Network [OSTI]

    Niu, Yunyun

    Radiation-induced DNA damage is a precursor to mutagenesis and cytotoxicity. During radiotherapy, exposure of healthy tissues can lead to severe side effects. We explored the potential of mitochondrial SOD (MnSOD) gene ...

  13. A case study of the radiative forcing of persistent contrails evolving into contrail-induced cirrus

    E-Print Network [OSTI]

    Allan, Richard P.

    . Aviation-induced cirrus can occur through two different pathways: via contrails spreading out exert a radiative forcing in both the shortwave (SW) solar spectrum and longwave (LW) terrestrial

  14. Pressure-sensitive blackbody point radiation induced by infrared diode laser irradiation

    E-Print Network [OSTI]

    Cao, Wenwu

    Pressure-sensitive blackbody point radiation induced by infrared diode laser irradiation Feng Qin,1, by irradiation of well-matched infrared (IR) lasers upon the Yb3 ions, ultrabroadband luminescence can

  15. Radiation-induced refraction artifacts in the optical CT readout of polymer gel dosimeters

    SciTech Connect (OSTI)

    Campbell, Warren G.; Jirasek, Andrew; Wells, Derek M.

    2014-11-01

    Purpose: The objective of this work is to demonstrate imaging artifacts that can occur during the optical computed tomography (CT) scanning of polymer gel dosimeters due to radiation-induced refractive index (RI) changes in polyacrylamide gels. Methods: A 1 L cylindrical polyacrylamide gel dosimeter was irradiated with 3 3 cm{sup 2} square beams of 6 MV photons. A prototype fan-beam optical CT scanner was used to image the dosimeter. Investigative optical CT scans were performed to examine two types of rayline bending: (i) bending within the plane of the fan-beam and (ii) bending out the plane of the fan-beam. To address structured errors, an iterative SavitzkyGolay (ISG) filtering routine was designed to filter 2D projections in sinogram space. For comparison, 2D projections were alternatively filtered using an adaptive-mean (AM) filter. Results: In-plane rayline bending was most notably observed in optical CT projections where rays of the fan-beam confronted a sustained dose gradient that was perpendicular to their trajectory but within the fan-beam plane. These errors caused distinct streaking artifacts in image reconstructions due to the refraction of higher intensity rays toward more opaque regions of the dosimeter. Out-of-plane rayline bending was observed in slices of the dosimeter that featured dose gradients perpendicular to the plane of the fan-beam. These errors caused widespread, severe overestimations of dose in image reconstructions due to the higher-than-actual opacity that is perceived by the scanner when light is bent off of the detector array. The ISG filtering routine outperformed AM filtering for both in-plane and out-of-plane rayline errors caused by radiation-induced RI changes. For in-plane rayline errors, streaks in an irradiated region (>7 Gy) were as high as 49% for unfiltered data, 14% for AM, and 6% for ISG. For out-of-plane rayline errors, overestimations of dose in a low-dose region (?50 cGy) were as high as 13 Gy for unfiltered data, 10 Gy for AM, and 3.1 Gy for ISG. The ISG routine also addressed unrelated artifacts that previously needed to be manually removed in sinogram space. However, the ISG routine blurred reconstructions, causing losses in spatial resolution of ?5 mm in the plane of the fan-beam and ?8 mm perpendicular to the fan-beam. Conclusions: This paper reveals a new category of imaging artifacts that can affect the optical CT readout of polyacrylamide gel dosimeters. Investigative scans show that radiation-induced RI changes can cause significant rayline errors when rays confront a prolonged dose gradient that runs perpendicular to their trajectory. In fan-beam optical CT, these errors manifested in two ways: (1) distinct streaking artifacts caused by in-plane rayline bending and (2) severe overestimations of opacity caused by rays bending out of the fan-beam plane and missing the detector array. Although the ISG filtering routine mitigated these errors better than an adaptive-mean filtering routine, it caused unacceptable losses in spatial resolution.

  16. Proteomic-based mechanistic investigation of low-dose radiation-induced cellular responses/effects

    SciTech Connect (OSTI)

    Chen, Xian

    2013-10-23

    The goal of our project is to apply our unique systems investigation strategy to reveal the molecular mechanisms underlying the radiation induction and transmission of oxidative damage, adaptive response, and bystander effect at low-doses. Beginning with simple in vitro systems such as fibroblast or epithelial pure culture, our amino acid-coded mass tagging (AACT) comparative proteomic platform will be used to measure quantitatively proteomic changes at high- or low-dose level with respect to their endogenous damage levels respectively, in which a broad range of unique regulated proteins sensitive to low-dose IR will be distinguished. To zoom in how these regulated proteins interact with other in the form of networks in induction/transmission pathways, these regulated proteins will be selected as baits for making a series of fibroblast cell lines that stably express each of them. Using our newly developed method of ?dual-tagging? quantitative proteomics that integrate the capabilities of natural complex expression/formation, simple epitope affinity isolation (not through tandem affinity purification or TAP), and ?in-spectra? AACT quantitative measurements using mass spectrometry (MS), we will be able to distinguish systematically interacting proteins with each bait in real time. Further, in addition to both proteome-wide (global differentially expressed proteins) and pathway-scale (bait-specific) profiling information, we will perform a computational network analysis to elucidate a global pathway/mechanisms underlying cellular responses to real-time low-dose IR. Similarly, we will extend our scheme to investigate systematically those induction/transmission pathways occurring in a fibroblast-epithelial interacting model in which the bystander cell (fibroblast) monitor the IR damage to the target cell (epithelial cell). The results will provide the proteome base (molecular mechanisms/pathways for signaling) for the low dose radiation-induced essential tissue environment interactions, including cell-cell, extracellular matrix and extracellular paracrine interactions.

  17. Mini-review Radiation-induced bystander effect: Early process and rapid assessment

    E-Print Network [OSTI]

    Yu, Peter K.N.

    brings potential hazards to normal tissues in radiotherapy, and imparts a higher risk from low-dose researches have been carried out on victims of atomic bomb explosions, occupational and accidental radiationMini-review Radiation-induced bystander effect: Early process and rapid assessment Hongzhi Wang

  18. Proling of Differentially Expressed Genes Induced by High Linear Energy Transfer Radiation

    E-Print Network [OSTI]

    epithelial cell lines irradiated with low doses of high linear energy transfer radiation and treatedProling of Differentially Expressed Genes Induced by High Linear Energy Transfer Radiation in Breast Epithelial Cells Debasish Roy,* Gloria Calaf, and Tom K. Hei Center for Radiological Research

  19. Degradation of silicon ac-coupled microstrip detectors induced by radiation

    SciTech Connect (OSTI)

    Bacchetta, N.; Gotra, Yu.; Bisello, D.; Canali, C.; Fuochi, P.G.; Paccagnella, A.; Verzellesi, G.

    1993-12-01

    Results are presented showing the radiation response of ac-coupled FOXFET biased microstrip detectors and related test patterns to be used in the microvertex detector of the CDF experiment at Fermi National Laboratory. Radiation tolerance of detectors to gamma and proton irradiation has been tested and the radiation induced variations of the dc electrical parameters have been analyzed. Long term post-irradiation behavior of detector characteristics have been studied, and the relevant room temperature annealing phenomena have been discussed.

  20. Mechanism of radiation-induced bystander effect: Role of the cyclooxygenase-2 signaling pathway

    E-Print Network [OSTI]

    Brenner, David Jonathan

    and carcinogenesis. At doses above 50 millisievert, the radiation- induced cancer risk can be estimated based, these irradiated cells. There is evidence that very low doses of -particles induced clastogenic responses by a particle (3, 5, 9). In CHO cells irradiated with low doses of particles where 1% of the nuclei were

  1. Ly{alpha} RADIATIVE TRANSFER IN COSMOLOGICAL SIMULATIONS USING ADAPTIVE MESH REFINEMENT

    SciTech Connect (OSTI)

    Laursen, Peter [Dark Cosmology Centre, Niels Bohr Institute, University of Copenhagen, Juliane Maries Vej 30, DK-2100, Copenhagen Oe (Denmark); Razoumov, Alexei O. [Institute for Computational Astrophysics, Department of Astronomy and Physics, Saint Mary's University, Halifax, NS, B3H3C3 (Canada); Sommer-Larsen, Jesper [Excellence Cluster Universe, Technische Universitaet Muenchen, Boltzmannstrasse 2, D-85748 Garching (Germany)], E-mail: pela@dark-cosmology.dk, E-mail: razoumov@ap.smu.ca, E-mail: jslarsen@astro.ku.dk

    2009-05-01

    A numerical code for solving various Ly{alpha} radiative transfer (RT) problems is presented. The code is suitable for an arbitrary, three-dimensional distribution of Ly{alpha} emissivity, gas temperature, density, and velocity field. Capable of handling Ly{alpha} RT in an adaptively refined grid-based structure, it enables detailed investigation of the effects of clumpiness of the interstellar (or intergalactic) medium. The code is tested against various geometrically and physically idealized configurations for which analytical solutions exist, and subsequently applied to three different simulated high-resolution 'Lyman-break galaxies', extracted from high-resolution cosmological simulations at redshift z = 3.6. Proper treatment of the Ly{alpha} scattering reveals a diversity of surface brightness (SB) and line profiles. Specifically, for a given galaxy the maximum observed SB can vary by an order of magnitude, and the total flux by a factor of 3-6, depending on the viewing angle. This may provide an explanation for differences in observed properties of high-redshift galaxies, and in particular a possible physical link between Lyman-break galaxies and regular Ly{alpha} emitters.

  2. Radiation induced strand breakage analyzed by tunel technique

    E-Print Network [OSTI]

    Reynolds, Marissa Dawn

    2003-01-01

    The objective of this research is to fully characterize the effectiveness and limits of using the terminal deoxynucleotidyl transferase mediated biotin-dUTP nick end labeling (TUNEL) technique for analysis of radiation ...

  3. Surface photoconductivity of organosilicate glass dielectrics induced by vacuum-ultraviolet radiation

    SciTech Connect (OSTI)

    Zheng, H.; Nichols, M. T.; Pei, D.; Shohet, J. L.; Nishi, Y.

    2013-08-14

    The temporary increase in the electrical surface conductivity of low-k organosilicate glass (SiCOH) during exposure to vacuum-ultraviolet radiation (VUV) is investigated. To measure the photoconductivity, patterned comb structures are deposited on dielectric films and exposed to synchrotron radiation in the range of 825 eV, which is in the energy range of most plasma vacuum-ultraviolet radiation. The change in photo surface conductivity induced by VUV radiation may be beneficial in limiting charging damage of dielectrics by depleting the plasma-deposited charge.

  4. Radiation-pressure-induced regenerative mechanical oscillations in

    E-Print Network [OSTI]

    with mechanical energy Temperature dependency = 300 K = 390 K P P #12;Summary and outlook All modes of the microtoroid Inflation : Optical energy Mechanical energy -- Red Doppler shift (-0) Deflation : Mechanical energy Optical energy -- Blue Doppler shift (+0) Pcirc Radiation pressure P1

  5. High and Low Doses of Ionizing Radiation Induce Different Secretome Profiles in a Human Skin Model

    SciTech Connect (OSTI)

    Zhang, Qibin; Matzke, Melissa M.; Schepmoes, Athena A.; Moore, Ronald J.; Webb-Robertson, Bobbie-Jo M.; Hu, Zeping; Monroe, Matthew E.; Qian, Weijun; Smith, Richard D.; Morgan, William F.

    2014-03-18

    It is postulated that secreted soluble factors are important contributors of bystander effect and adaptive responses observed in low dose ionizing radiation. Using multidimensional liquid chromatography-mass spectrometry based proteomics, we quantified the changes of skin tissue secretome the proteins secreted from a full thickness, reconstituted 3-dimensional skin tissue model 48 hr after exposure to 3, 10 and 200 cGy of X-rays. Overall, 135 proteins showed statistical significant difference between the sham (0 cGy) and any of the irradiated groups (3, 10 or 200 cGy) on the basis of Dunnett adjusted t-test; among these, 97 proteins showed a trend of downregulation and 9 proteins showed a trend of upregulation with increasing radiation dose. In addition, there were 21 and 8 proteins observed to have irregular trends with the 10 cGy irradiated group either having the highest or the lowest level among all three radiated doses. Moreover, two proteins, carboxypeptidase E and ubiquitin carboxyl-terminal hydrolase isozyme L1 were sensitive to ionizing radiation, but relatively independent of radiation dose. Conversely, proteasome activator complex subunit 2 protein appeared to be sensitive to the dose of radiation, as rapid upregulation of this protein was observed when radiation doses were increased from 3, to 10 or 200 cGy. These results suggest that different mechanisms of action exist at the secretome level for low and high doses of ionizing radiation.

  6. Non-Targeted Effects Induced by Ionizing Radiation: Mechanisms and Potential Impact on Radiation Induced Health Effects

    SciTech Connect (OSTI)

    Morgan, William F.; Sowa, Marianne B.

    2015-01-01

    Not-targeted effects represent a paradigm shift from the "DNA centric" view that ionizing radiation only elicits biological effects and subsequent health consequences as a result of an energy deposition event in the cell nucleus. While this is likely true at higher radiation doses (> 1Gy), at low doses (< 100mGy) non-targeted effects associated with radiation exposure might play a significant role. Here definitions of non-targeted effects are presented, the potential mechanisms for the communication of signals and signaling networks from irradiated cells/tissues are proposed, and the various effects of this intra- and intercellular signaling are described. We conclude with speculation on how these observations might lead to and impact long-term human health outcomes.

  7. Stress-related phenomena in transient radiation-induced absorption in optical fibers

    SciTech Connect (OSTI)

    Looney, L.D.; Lyons, P.B.; Kelly, R.E.

    1988-01-01

    The optical properties of materials can be modified by exposure to radiation and research to investigate these radiation-induced phenomena has intensified over the last several decades. The advent of optical fiber technology and the many applications of optical fiber for information transmission have sharply increased the interest in these investigations. Optical fibers present a long optical transmission path and that path may traverse different adverse environments, including radiation areas. The long tranmission path provides increased potential for interactions between the optical information signal and the optical medium. 10 refs., 10 figs.

  8. Sorafenib Enhances Radiation-Induced Apoptosis in Hepatocellular Carcinoma by Inhibiting STAT3

    SciTech Connect (OSTI)

    Huang, Chao-Yuan [Department of Oncology, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei, Taiwan (China) [Department of Oncology, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei, Taiwan (China); Department of Radiological Technology, Yuanpei University, Hsinchu, Taiwan (China); Lin, Chen-Si [School of Veterinary Medicine, National Taiwan University Hospital, Taipei, Taiwan (China)] [School of Veterinary Medicine, National Taiwan University Hospital, Taipei, Taiwan (China); Tai, Wei-Tien; Hsieh, Chi-Ying [Department of Medical Research, National Taiwan University Hospital, Taipei, Taiwan (China) [Department of Medical Research, National Taiwan University Hospital, Taipei, Taiwan (China); National Center of Excellence for Clinical Trial and Research, National Taiwan University Hospital, Taipei, Taiwan (China); Shiau, Chung-Wai [Institute of Biopharmaceutical Sciences, National Yang-Ming University, Taipei, Taiwan (China)] [Institute of Biopharmaceutical Sciences, National Yang-Ming University, Taipei, Taiwan (China); Cheng, Ann-Lii [Department of Oncology, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei, Taiwan (China) [Department of Oncology, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei, Taiwan (China); National Center of Excellence for Clinical Trial and Research, National Taiwan University Hospital, Taipei, Taiwan (China); Chen, Kuen-Feng, E-mail: kfchen1970@ntu.edu.tw [Department of Medical Research, National Taiwan University Hospital, Taipei, Taiwan (China) [Department of Medical Research, National Taiwan University Hospital, Taipei, Taiwan (China); National Center of Excellence for Clinical Trial and Research, National Taiwan University Hospital, Taipei, Taiwan (China)

    2013-07-01

    Purpose: Hepatocellular carcinoma (HCC) is one of the most common and lethal human malignancies. Lack of efficient therapy for advanced HCC is a pressing problem worldwide. This study aimed to determine the efficacy and mechanism of combined sorafenib and radiation therapy treatment for HCC. Methods and Materials: HCC cell lines (PLC5, Huh-7, Sk-Hep1, and Hep3B) were treated with sorafenib, radiation, or both, and apoptosis and signal transduction were analyzed. Results: All 4 HCC cell lines showed resistance to radiation-induced apoptosis; however, this resistance could be reversed in the presence of sorafenib. Inhibition of phospho-STAT3 was found in cells treated with sorafenib or sorafenib plus radiation and subsequently reduced the expression levels of STAT3-related proteins, Mcl-1, cyclin D1, and survivin. Silencing STAT3 by RNA interference overcame apoptotic resistance to radiation in HCC cells, and the ectopic expression of STAT3 in HCC cells abolished the radiosensitizing effect of sorafenib. Moreover, sorafenib plus radiation significantly suppressed PLC5 xenograft tumor growth. Conclusions: These results indicate that sorafenib sensitizes resistant HCC cells to radiation-induced apoptosis via downregulating phosphorylation of STAT3 in vitro and in vivo.

  9. Galactic cosmic ray induced radiation dose on terrestrial exoplanets

    E-Print Network [OSTI]

    Atri, Dimitra; Griessmeier, Jean-Mathias

    2013-01-01

    This past decade has seen tremendous advancements in the study of extrasolar planets. Observations are now made with increasing sophistication from both ground and space based instruments, and exoplanets are characterized with increasing precision. There is a class of particularly interesting exoplanets, falling in the habitable zone, which is defined as the area around a star where the planet is capable of supporting liquid water on its surface. Theoretical calculations also suggest that close-in exoplanets are more likely to have weaker planetary magnetic fields, especially in case of super earths. Such exoplanets are subjected to a high flux of Galactic Cosmic Rays (GCRs) due to their weak magnetic moments. GCRs are energetic particles of astrophysical origin, which strike the planetary atmosphere and produce secondary particles, including muons, which are highly penetrating. Some of these particles reach the planetary surface and contribute to the radiation dose. Along with the magnetic field, another fac...

  10. Ionizing radiation induced leakage current on ultra-thin gate oxides

    SciTech Connect (OSTI)

    Scarpa, A.; Paccagnella, A.; Montera, F.; Ghibaudo, G.; Pananakakis, G.; Fuochi, P.G.

    1997-12-01

    MOS capacitors with a 4.4 nm thick gate oxide have been exposed to {gamma} radiation from a Co{sup 60} source. As a result, the authors have measured a stable leakage current at fields lower than those required for Fowler-Nordheim tunneling. This Radiation Induced Leakage Current (RILC) is similar to the usual Stress Induced Leakage Currents (SILC) observed after electrical stresses of MOS devices. They have verified that these two currents share the same dependence on the oxide field, and the RILC contribution can be normalized to an equivalent injected charge for Constant Current Stresses. They have also considered the dependence of the RILC from the cumulative radiation dose, and from the applied bias during irradiation, suggesting a correlation between RILC and the distribution of trapped holes and neutral levels in the oxide layer.

  11. The innate and adaptive immune response induced by alveolar macrophages exposed to ambient particulate matter

    SciTech Connect (OSTI)

    Miyata, Ryohei; Eeden, Stephan F. van

    2011-12-15

    Emerging epidemiological evidence suggests that exposure to particulate matter (PM) air pollution increases the risk of cardiovascular events but the exact mechanism by which PM has adverse effects is still unclear. Alveolar macrophages (AM) play a major role in clearing and processing inhaled PM. This comprehensive review of research findings on immunological interactions between AM and PM provides potential pathophysiological pathways that interconnect PM exposure with adverse cardiovascular effects. Coarse particles (10 {mu}m or less, PM{sub 10}) induce innate immune responses via endotoxin-toll-like receptor (TLR) 4 pathway while fine (2.5 {mu}m or less, PM{sub 2.5}) and ultrafine particles (0.1 {mu}m or less, UFP) induce via reactive oxygen species generation by transition metals and/or polyaromatic hydrocarbons. The innate immune responses are characterized by activation of transcription factors [nuclear factor (NF)-{kappa}B and activator protein-1] and the downstream proinflammatory cytokine [interleukin (IL)-1{beta}, IL-6, and tumor necrosis factor-{alpha}] production. In addition to the conventional opsonin-dependent phagocytosis by AM, PM can also be endocytosed by an opsonin-independent pathway via scavenger receptors. Activation of scavenger receptors negatively regulates the TLR4-NF-{kappa}B pathway. Internalized particles are subsequently subjected to adaptive immunity involving major histocompatibility complex class II (MHC II) expression, recruitment of costimulatory molecules, and the modulation of the T helper (Th) responses. AM show atypical antigen presenting cell maturation in which phagocytic activity decreases while both MHC II and costimulatory molecules remain unaltered. PM drives AM towards a Th1 profile but secondary responses in a Th1- or Th-2 up-regulated milieu drive the response in favor of a Th2 profile.

  12. Radio Wave 'Messengers' of Periodic Gravitational Radiation and the Problem of Gravitationally Induced Nonlinearity in Electrodynamic Systems

    E-Print Network [OSTI]

    A. B. Balakin; Z. G. Murzakhanov; G. V. Kisun'ko

    2005-11-10

    We discuss a gravitationally induced nonlinearity in hierarchic systems. We consider the generation of extremely low-frequency radio waves with a frequency of the periodic gravitational radiation; the generation is due to an induced nonlinear self-action of electromagnetic radiation in the vicinity of the gravitational-radiation source. These radio waves are a fundamentally new type of response of an electrodynamic system to gravitational radiation. That is why we here use an unconventional term: radio-wave messengers of periodic gravitational radiation.

  13. Effects of estrogen and gender on cataractogenesis induced by high-LET radiation

    SciTech Connect (OSTI)

    Henderson, M.A.; Rusek, A.; Valluri, S.; Garrett, J.; Lopez, J.; Caperell-Grant, A.; Mendonca, M.; Bigsby, R.; Dynlacht, J.

    2010-02-01

    Planning for long-duration manned lunar and interplanetary missions requires an understanding of radiation-induced cataractogenesis. Previously, it was demonstrated that low-linear energy transfer (LET) irradiation with 10 Gy of {sup 60}Co {gamma} rays resulted in an increased incidence of cataracts in male rats compared to female rats. This gender difference was not due to differences in estrogen, since male rats treated with the major secreted estrogen 17-{beta}-estradiol (E2) showed an identical increase compared to untreated males. We now compare the incidence and rate of progression of cataracts induced by high-LET radiation in male and female Sprague-Dawley rats. Rats received a single dose of 1 Gy of 600 MeV {sup 56}Fe ions. Lens opacification was measured at 2-4 week intervals with a slit lamp. The incidence and rate of progression of radiation-induced cataracts was significantly increased in the animals in which estrogen was available from endogenous or exogenous sources. Male rats with E2 capsules implanted had significantly higher rates of progression compared to male rats with empty capsules implanted (P = 0.025) but not compared to the intact female rats. These results contrast with data obtained after low-LET irradiation and suggest the possibility that the different types of damage caused by high- and low-LET radiation may be influenced differentially by steroid sex hormones.

  14. Photon Radiation and Dilepton Production Induced by Rescattering in Strong Interacting Medium

    E-Print Network [OSTI]

    Hanzhong Zhang; Zhongbo Kang; Ben-Wei Zhang; Enke Wang

    2008-04-27

    Using the opacity expansion technique we investigate the photon radiation and dilepton production induced by multiple rescattering as energetic parton jet passing through the strong interacting medium. The real photon radiation and dilepton invariant-mass spectrums of the bremsstrahlung contribution from an energetic quark jet are presented. The leading contribution of total energy loss by photon emmision in medium of a higher energy quark jet is found to be proportional to the jet energy and has a linear dependence on the thickness of the nuclear target. The rescattering contribution for the dilepton is important only for small value of the invariant-mass and for the not so fast jet. The contribution fraction of the dilepton induced by rescattering in medium is found to be nearly a constant when the ratio of jet energy to Debye screening mass $E/\\mu$ is large.

  15. Irradiation Induced Precipitation and Dissolution of Intermetallics in Zr Alloys Studied Using Synchrotron Radiation

    SciTech Connect (OSTI)

    Arthur T. Motta

    2004-09-21

    The overall aim of this project is to investigate the irradiation induced precipitation of alloying elements and dissolution of second phase particles in Zr alloys using a combination of (1) synchrotron radiation examination of bulk samples using the Advanced Photon Source (APS) at Argonne National Laboratory and (2) in-situ irradiation of model alloys using the IVEM/Tandem Facility also located at Argonne

  16. Spatiotemporal characterization of ionizing radiation induced DNA damage foci and their relation to chromatin organization

    SciTech Connect (OSTI)

    Costes, Sylvain V; Chiolo, Irene; Pluth, Janice M.; Barcellos-Hoff, Mary Helen; Jakob, Burkhard

    2009-09-15

    DNA damage sensing proteins have been shown to localize to the sites of DSB within seconds to minutes following ionizing radiation (IR) exposure, resulting in the formation of microscopically visible nuclear domains referred to as radiation-induced foci (RIF). This review characterizes the spatio-temporal properties of RIF at physiological doses, minutes to hours following exposure to ionizing radiation, and it proposes a model describing RIF formation and resolution as a function of radiation quality and nuclear densities. Discussion is limited to RIF formed by three interrelated proteins ATM (Ataxia telangiectasia mutated), 53BP1 (p53 binding protein 1) and ?H2AX (phosphorylated variant histone H2AX). Early post-IR, we propose that RIF mark chromatin reorganization, leading to a local nuclear scaffold rigid enough to keep broken DNA from diffusing away, but open enough to allow the repair machinery. We review data indicating clear kinetic and physical differences between RIF emerging from dense and uncondensed regions of the nucleus. At later time post-IR, we propose that persistent RIF observed days following exposure to ionizing radiation are nuclear ?scars? marking permanent disruption of the chromatin architecture. When DNA damage is resolved, such chromatin modifications should not necessarily lead to growth arrest and it has been shown that persistent RIF can replicate during mitosis. Thus, heritable persistent RIF spanning over tens of Mbp may affect the transcriptome of a large progeny of cells. This opens the door for a non DNA mutation-based mechanism of radiation-induced phenotypes.

  17. Rain-Induced Increase in Background Radiation Detected by Radiation Portal Monitors

    SciTech Connect (OSTI)

    Hausladen, Paul; Blessinger, Christopher S; Guzzardo, Tyler; Livesay, Jake

    2012-07-01

    A complete understanding of both the steady state and transient background measured by Radiation Portal Monitors (RPMs) is essential to predictable system performance, as well as maximization of detection sensitivity. To facilitate this understanding, a test bed for the study of natural background in RPMs has been established at the Oak Ridge National Laboratory. This work was performed in support of the Second Line of Defense Program's mission to detect the illicit movement of nuclear material. In the present work, transient increases in gamma ray counting rates in RPMs due to rain are investigated. The increase in background activity associated with rain, which has been well documented in the field of environmental radioactivity, originates from the atmospheric deposition of two radioactive daughters of radon-222, namely lead-214 and bismuth-214 (henceforth {sup 222}Rn, {sup 214}Pb and {sup 214}Bi). In this study, rainfall rates recorded by a co-located weather station are compared with RPM count rates and High Purity Germanium spectra. The data verifies these radionuclides are responsible for the dominant transient natural background fluctuations in RPMs. Effects on system performance and potential mitigation strategies are discussed.

  18. Endogenous retrovirus and radiation-induced leukemia in the RMF mouse

    SciTech Connect (OSTI)

    Tennant, R.W.; Boone, L.R.; Lalley, P.; Yang, W.K.

    1982-01-01

    The induction of myeloid leukemia in irradiated RFM/Un mice has been associated with retrovirus infection. However, two characteristics of this strain complicate efforts to define the role of the virus. This strain possesses only one inducible host range class of endogenous virus and a unique gene, in addition to the Fv-1/sup n/ locus, which specifically restricts exogenous infection by endogenous viruses. These characteristics possibly account for absence of recombinant viruses in this strain, even though virus is amply expressed during most of the animal's life span. We have examined further the distribution of retrovirus sequences and the chromosomal locus of the inducible virus in this strain. This report describes evidence for additional viral sequences in cells of a radiation-induced myeloid leukemia line and discusses the possible origin of these added copies.

  19. MicroRNA Regulation of Ionizing Radiation-Induced Premature Senescence

    SciTech Connect (OSTI)

    Wang Yong; Scheiber, Melissa N.; Neumann, Carola; Calin, George A.; Zhou Daohong

    2011-11-01

    Purpose: MicroRNAs (miRNAs) have emerged as critical regulators of many cellular pathways. Ionizing radiation (IR) exposure causes DNA damage and induces premature senescence. However, the role of miRNAs in IR-induced senescence has not been well defined. Thus, the purpose of this study was to identify and characterize senescence-associated miRNAs (SA-miRNAs) and to investigate the role of SA-miRNAs in IR-induced senescence. Methods and Materials: In human lung (WI-38) fibroblasts, premature senescence was induced either by IR or busulfan (BU) treatment, and replicative senescence was accomplished by serial passaging. MiRNA microarray were used to identify SA-miRNAs, and real-time reverse transcription (RT)-PCR validated the expression profiles of SA-miRNAs in various senescent cells. The role of SA-miRNAs in IR-induced senescence was characterized by knockdown of miRNA expression, using anti-miRNA oligonucleotides or by miRNA overexpression through the transfection of pre-miRNA mimics. Results: We identified eight SA-miRNAs, four of which were up-regulated (miR-152, -410, -431, and -493) and four which were down-regulated (miR-155, -20a, -25, and -15a), that are differentially expressed in both prematurely senescent (induced by IR or BU) and replicatively senescent WI-38 cells. Validation of the expression of these SA-miRNAs indicated that down-regulation of miR-155, -20a, -25, and -15a is a characteristic miRNA expression signature of cellular senescence. Functional analyses revealed that knockdown of miR-155 or miR-20a, but not miR-25 or miR-15a, markedly enhanced IR-induced senescence, whereas ectopic overexpression of miR-155 or miR-20a significantly inhibited senescence induction. Furthermore, our studies indicate that miR-155 modulates IR-induced senescence by acting downstream of the p53 and p38 mitogen-activated protein kinase (MAPK) pathways and in part via regulating tumor protein 53-induced nuclear protein 1 (TP53INP1) expression. Conclusion: Our results suggest that SA-miRNAs are involved in the regulation of IR-induced senescence, so targeting these miRNAs may be a novel approach for modulating cellular response to radiation exposure.

  20. 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; Pan, Xiaoning; Zhou, Yin; Wang, Xiaochun; Du, Weiliang; Kudchadker, Rajat J.; Johnson, Jennifer L.; Kuban, Deborah A.; Lee, Andrew K.; Zhang, Xiaodong

    2013-08-01

    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 dosevolume 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.

  1. Mitigation and Treatment of Radiation-Induced Thoracic Injury With a Cyclooxygenase-2 Inhibitor, Celecoxib

    SciTech Connect (OSTI)

    Hunter, Nancy R.; Valdecanas, David [Department of Experimental Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States)] [Department of Experimental Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Liao Zhongxing [Division of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States)] [Division of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Milas, Luka [Department of Experimental Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States)] [Department of Experimental Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Thames, Howard D. [Department of Biostatistics, University of Texas MD Anderson Cancer Center, Houston, Texas (United States)] [Department of Biostatistics, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Mason, Kathy A., E-mail: kmason@mdanderson.org [Department of Experimental Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States)

    2013-02-01

    Purpose: To test whether a cyclooxygenase-2 inhibitor (celecoxib) could reduce mortality resulting from radiation-induced pneumonitis. Methods and Materials: Celecoxib was given to mice twice daily for 40 consecutive days starting on the day of local thoracic irradiation (LTI) or 40 or 80 days later. C3Hf/KamLaw mice were observed for morbidity, and time to death was determined. Results were analyzed using the Cox proportional hazards model. Results: Timing of celecoxib relative to LTI determined efficacy. A significant reduction in time to death was achieved only when celecoxib was started 80 days after LTI, corresponding to the time when pneumonitis is expressed. For these mice the reduction in mortality was quantified as a hazard ratio for mortality of treated vs untreated of 0.36 (95% confidence interval [CI] 0.24-0.53), thus significantly less than 1.0. Correspondingly, the median lethal dose for treated mice (12.9 Gy; 95% CI 12.55-13.25 Gy) was significantly (P=.026) higher than for untreated mice (12.4 Gy; 95% CI 12.2-12.65 Gy). Conclusions: Celecoxib significantly reduced lung toxicity when administered months after LTI when the deleterious effects of radiation were expressed. The schedule-dependent reduction in fatal pneumonitis suggests that celecoxib could be clinically useful by reintroduction of treatment months after completion of radiation therapy. These findings may be important for designing clinical trials using cyclooxygenase-2 inhibitors to treat radiation-induced lung toxicity as a complement to concurrent radiation therapy of lung cancers.

  2. Normal Tissue Complication Probability Modeling of Radiation-Induced Hypothyroidism After Head-and-Neck Radiation Therapy

    SciTech Connect (OSTI)

    Bakhshandeh, Mohsen; Hashemi, Bijan; Mahdavi, Seied Rabi Mehdi; Nikoofar, Alireza; Vasheghani, Maryam; Kazemnejad, Anoshirvan

    2013-02-01

    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.

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

    SciTech Connect (OSTI)

    Azuddin, A. Yusof; Rahman, I. Abdul; Mohamed, F.; Siah, N. J.; Saadc, M.; Ismail, F.

    2014-09-03

    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.

  4. Detecting gravitational radiation from neutron stars using a six-parameter adaptive MCMC method

    E-Print Network [OSTI]

    Richard Umsttter; Renate Meyer; Rjean J. Dupuis; John Veitch; Graham Woan; Nelson Christensen

    2004-04-06

    We present a Markov chain Monte Carlo technique for detecting gravitational radiation from a neutron star in laser interferometer data. The algorithm can estimate up to six unknown parameters of the target, including the rotation frequency and frequency derivative, using reparametrization, delayed rejection and simulated annealing. We highlight how a simple extension of the method, distributed over multiple computer processors, will allow for a search over a narrow frequency band. The ultimate goal of this research is to search for sources at a known locations, but uncertain spin parameters, such as may be found in SN1987A.

  5. Symmetry Adapted Coherent States for Three-Level Atoms Interacting with One-Mode Radiation

    E-Print Network [OSTI]

    R. Lpez-Pea; S. Cordero; E. Nahmad-Achar; O. Castaos

    2015-10-21

    We introduce a combination of coherent states as variational test functions for the atomic and radiation sectors to describe a system of Na three- level atoms interacting with a one-mode quantised electromagnetic field, with and without the rotating wave approximation, which preserves the symmetry presented by the Hamiltonian. These provide us with the possibility of finding analytical solutions for the ground and first excited states. We study the properties of these solutions for the V-configuration in the double resonance condition, and calculate the expectation values of the number of photons, the atomic populations, the total number of excitations, and their corresponding fluctuations. We also calculate the photon number distribution and the linear entropy of the reduced density matrix to estimate the entanglement between matter and radiation. For the first time, we exhibit analytical expressions for all of these quantities, as well as an analytical description for the phase diagram in parameter space, which distinguishes the normal and collective regions, and which gives us all the quantum phase transitions of the ground state from one region to the other as we vary the interaction parameters (the matter-field coupling constants) of the model, in functional form.

  6. Radiation-Induced Decomposition of PETN and TATB under Extreme Conditions

    SciTech Connect (OSTI)

    Giefers, Hubertus; Pravica, Michael

    2008-11-03

    We conducted a series of experiments investigating decomposition of secondary explosives PETN and TATB at varying static pressures and temperatures using synchrotron radiation. As seen in our earlier work, the decomposition rate of TATB at ambient temperature slows systematically with increasing pressure up to at least 26 GPa but varies little with pressure in PETN at ambient temperature up to 15.7 GPa, yielding important information pertaining to the activation complex volume in both cases. We also investigated the radiation-induced decomposition rate as a function of temperature at ambient pressure and 26 GPa for TATB up to 403 K, observing that the decomposition rate increases with increasing temperature as expected. The activation energy for the TATB reaction at ambient temperature was experimentally determined to be 16 {+-} 3 kJ/mol.

  7. Radiation reaction induced non-monotonic features in runaway electron distributions

    E-Print Network [OSTI]

    Hirvijoki, E; Decker, J; Embreus, O; Stahl, A; Flp, T

    2015-01-01

    Runaway electrons, which are generated in a plasma where the induced electric field exceeds a certain critical value, can reach very high energies in the MeV range. For such energetic electrons, radiative losses will contribute significantly to the momentum space dynamics. Under certain conditions, due to radiative momentum losses, a non-monotonic feature - a "bump" - can form in the runaway electron tail, creating a potential for bump-on-tail-type instabilities to arise. Here we study the conditions for the existence of the bump. We derive an analytical threshold condition for bump appearance and give an approximate expression for the minimum energy at which the bump can appear. Numerical calculations are performed to support the analytical derivations.

  8. Remote sensor response study in the regime of the microwave radiation-induced magnetoresistance oscillations

    SciTech Connect (OSTI)

    Ye, Tianyu; Mani, R. G. [Department of Physics and Astronomy, Georgia State University, Atlanta, Georgia 30303 (United States)] [Department of Physics and Astronomy, Georgia State University, Atlanta, Georgia 30303 (United States); Wegscheider, W. [Laboratorium fr Festkrperphysik, ETH Zrich, 8093 Zrich (Switzerland)] [Laboratorium fr Festkrperphysik, ETH Zrich, 8093 Zrich (Switzerland)

    2013-11-04

    A concurrent remote sensing and magneto-transport study of the microwave excited two dimensional electron system (2DES) at liquid helium temperatures has been carried out using a carbon detector to remotely sense the microwave activity of the 2D electron system in the GaAs/AlGaAs heterostructure during conventional magneto-transport measurements. Various correlations are observed and reported between the oscillatory magnetotransport and the remotely sensed reflection. In addition, the oscillatory remotely sensed signal is shown to exhibit a power law type variation in its amplitude, similar to the radiation-induced magnetoresistance oscillations.

  9. 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)

    2012-11-01

    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.

  10. ADC response to radiation therapy correlates with induced changes in radiosensitivity

    SciTech Connect (OSTI)

    Larocque, Matthew P.; Syme, Alasdair; Allalunis-Turner, Joan; Fallone, B. Gino [Department of Medical Physics, Cross Cancer Institute, 11560 University Avenue, Edmonton, Alberta T6G 1Z2 (Canada) and Department of Physics, University of Alberta, 11560 University Avenue, Edmonton, Alberta T6G 1Z2 (Canada); Department of Medical Physics, Cross Cancer Institute, 11560 University Avenue, Edmonton, Alberta T6G 1Z2 (Canada) and Department of Oncology, University of Alberta, 11560 University Avenue, Edmonton, Alberta T6G 1Z2 (Canada); Department of Experimental Oncology, Cross Cancer Institute, 11560 University Avenue, Edmonton, Alberta T6G 1Z2 (Canada) and Department of Oncology, University of Alberta, 11560 University Avenue, Edmonton, Alberta T6G 1Z2 (Canada); Department of Medical Physics, Cross Cancer Institute, 11560 University Avenue, Edmonton, Alberta T6G 1Z2 (Canada); Department of Oncology, University of Alberta, 11560 University Avenue, Edmonton, Alberta T6G 1Z2 (Canada) and Department of Physics, University of Alberta, 11560 University Avenue, Edmonton, Alberta T6G 1Z2 (Canada)

    2010-07-15

    Purpose: Magnetic resonance imaging was used to compare the responses of human glioma tumor xenografts to a single fraction of radiation, where a change in radiosensitivity was induced by use of a suture-based ligature. Methods: Ischemia was induced by use of a suture-based ligature. Six mice were treated with 800 cGy of 200 kVp x rays while the ligature was applied. An additional six mice had the ligature applied for the same length of time but were not irradiated. Quantitative maps of each tumor were produced of water apparent diffusion coefficient (ADC) and transverse relaxation time (T2). Mice were imaged before and at multiple points after treatment. Volumetric, ADC, and T2 responses of the ligated groups were compared to previously measured responses of the same tumor model to the same radiation treatment, as well as those from an untreated control group. Results: Application of the ligature without irradiation did not affect tumor ADC values, but did produce a temporary decrease in tumor T2 values. Average tumor T2 was reduced by 6.2% 24 h after the ligature was applied. Average tumor ADC increased by 9.6% 7 days after irradiation with a ligature applied. This response was significantly less than that observed in the same tumor model when no ligature is present (21.8% at 7 days after irradiation). Conclusions: These observations indicate that the response of ADC to radiation therapy is not determined entirely by physical dose deposition, but at least in part by radiosensitivity and resultant biological response.

  11. Thermoacoustic emission induced by deeply-penetrating radiation and its application to biomedical imaging

    SciTech Connect (OSTI)

    Liew, Soo Chin.

    1989-01-01

    Thermoacoustic emissions induced by 2450 MHz microwave pulses in water, tissue-simulating phantoms and dog kidneys have been detected. The analytic signal magnitude has been employed in generating A-mode images with excellent depth resolution. Thermoacoustic emissions have also been detected from the dose-gradient at the beam edges of a 4 MeV x-ray beam in water. These results establish the feasibility of employing thermoacoustic signals in generating diagnostic images, and in locating x-ray beam edges during radiation therapy. A theoretical model for thermoacoustic imaging using a directional transducer has been developed, which may be used in the design of future thermoacoustic imaging system, and in facilitating comparisons with other types of imaging systems. A method of characterizing biological tissues has been proposed, which relates the power spectrum of the detected thermoacoustic signals to the autocorrelation function of the thermoacoustic source distribution in the tissues. The temperature dependence of acoustic signals induced by microwave pulses in water has been investigated. A microwave-induced thermoacoustic source capable of launching large aperture, unipolar ultrasonic plane wave pulses in water has been constructed.

  12. Epidermal growth factor receptor expression in radiation-induced dog lung tumors by immunocytochemical localization

    SciTech Connect (OSTI)

    Leung, F.L.; Park, J.F.; Dagle, G.E.

    1993-06-01

    In studies to determine the role of growth factors in radiation-induced lung cancer, epidermal growth factor (EGFR) expression was examined by immunocytochemistry in 51 lung tumors from beagle dogs exposed to inhaled plutonium; 21 of 51 (41%) tumors were positive for EGFR. The traction of tumors positive for EGFR and the histological type of EGFR-positive tumors in the plutonium-exposed dogs were not different from spontaneous dog lung tumors, In which 36% were positive for EGFR. EGFR involvement in Pu-induced lung tumors appeared to be similar to that in spontaneous lung tumors. However, EGFR-positive staining was observed in only 1 of 16 tumors at the three lowest Pu exposure levels, compared to 20 of 35 tumors staining positive at the two highest Pu exposure levels. The results in dogs were in good agreement with the expression of EGFR reported in human non-small cell carcinoma of the lung, suggesting that Pu-induced lung tumors in the dog may be a suitable animal model to investigate the role of EGFR expression in lung carcinogenesis. In humans, EGFR expression in lung tumors has been primarily related to histological tumor types. In individual dogs with multiple primary lung tumors, the tumors were either all EGFR positive or EGFR negative, suggesting that EGFR expression may be related to the response of the individual dog as well as to the histological type of tumor.

  13. Roles of Sensory Nerves in the Regulation of Radiation-Induced Structural and Functional Changes in the Heart

    SciTech Connect (OSTI)

    Sridharan, Vijayalakshmi; Tripathi, Preeti [Department of Pharmaceutical Sciences, Division of Radiation Health, University of Arkansas for Medical Sciences, Little Rock, Arkansas (United States); Sharma, Sunil [Department of Radiation Oncology, Division of Radiation Health, University of Arkansas for Medical Sciences, Little Rock, Arkansas (United States); Moros, Eduardo G. [Department of Radiation Oncology, Moffitt Cancer Center and Research Institute, Tampa, Florida (United States); Zheng, Junying [Department of Pharmaceutical Sciences, Division of Radiation Health, University of Arkansas for Medical Sciences, Little Rock, Arkansas (United States); Hauer-Jensen, Martin [Department of Pharmaceutical Sciences, Division of Radiation Health, University of Arkansas for Medical Sciences, Little Rock, Arkansas (United States); Surgical Service, Central Arkansas Veterans Healthcare System, Little Rock, Arkansas (United States); Boerma, Marjan, E-mail: mboerma@uams.edu [Department of Pharmaceutical Sciences, Division of Radiation Health, University of Arkansas for Medical Sciences, Little Rock, Arkansas (United States)

    2014-01-01

    Purpose: Radiation-induced heart disease (RIHD) is a chronic severe side effect of radiation therapy of intrathoracic and chest wall tumors. The heart contains a dense network of sensory neurons that not only are involved in monitoring of cardiac events such as ischemia and reperfusion but also play a role in cardiac tissue homeostasis, preconditioning, and repair. The purpose of this study was to examine the role of sensory nerves in RIHD. Methods and Materials: Male Sprague-Dawley rats were administered capsaicin to permanently ablate sensory nerves, 2 weeks before local image-guided heart x-ray irradiation with a single dose of 21 Gy. During the 6 months of follow-up, heart function was assessed with high-resolution echocardiography. At 6 months after irradiation, cardiac structural and molecular changes were examined with histology, immunohistochemistry, and Western blot analysis. Results: Capsaicin pretreatment blunted the effects of radiation on myocardial fibrosis and mast cell infiltration and activity. By contrast, capsaicin pretreatment caused a small but significant reduction in cardiac output 6 months after irradiation. Capsaicin did not alter the effects of radiation on cardiac macrophage number or indicators of autophagy and apoptosis. Conclusions: These results suggest that sensory nerves, although they play a predominantly protective role in radiation-induced cardiac function changes, may eventually enhance radiation-induced myocardial fibrosis and mast cell activity.

  14. Low doses ionizing radiation enhances the invasiveness of breast cancer cells by inducing epithelial-mesenchymal transition

    SciTech Connect (OSTI)

    Zhang, Xin; Li, Xiaoyan; Zhang, Ning; Yang, Qifeng; Moran, Meena S.

    2011-08-19

    Highlights: {yields} Low doses ionizing irradiation would enhance the invasiveness of breast cancer cells by inducing EMT. {yields} Low doses ionizing radiation induced morphologic changes in breast cancer cells. {yields} Low doses ionizing radiation led to upregulation of mesenchymal markers and down-regulation of epithelial markers. {yields} Low doses ionizing radiation increased migration and invasion of breast cancer cells. -- Abstract: Epithelial-mesenchymal transition (EMT) is a process cellular morphologic and molecular alterations facilitate cell invasion. We hypothesized that low dose ionizing irradiation (LDIR) enhances the invasiveness of breast cancer cells by inducing EMT. The effects of LDIR on cellular morphology and the EMT markers of MCF-7 breast cancer cells were analyzed by western blot/RT-PCR and migration/invasion was examined using the transwell assay. We found that LDIR led to the phenotypic changes of EMT in MCF-7 cells and down-regulation of epithelial differentiation markers and transcriptional induction of mesenchymal markers. Furthermore, the radiated cells demonstrated enhanced migration/invasion MCF-7 cells compared with non-radiated cells. In summary, LDIR promotes the invasiveness of breast cancer cells through epithelial to mesenchymal transition. These findings may ultimately provide a new targeted approach for improving the therapeutic effectiveness of radiation in breast cancer.

  15. Mirror effect induced by the dilaton field on the Hawking radiation

    SciTech Connect (OSTI)

    Maeda, Kengo; Okamura, Takashi

    2006-11-03

    A ''stringy particle'' action is naturally derived from Kaluza-Klein compactification of a test string action coupled to the dilaton field in a conformally invariant manner. According to the standard procedure, we perform the second quantization of the stringy particle. As an interesting application, we consider evaporation of a near-extremal dilatonic black hole by Hawking radiation via the stringy particles. We show that a mirror surface which reflects them is induced by the dilaton field outside the the horizon when the size of the black hole is comparable to the Planck scale. As a result, the energy flux does not propagate across the surface, and hence the evaporation of the dilatonic black hole stops just before the naked singularity at the extremal state appears even though the surface gravity is non-zero in the extremal limit.

  16. Prompt radiation-induced conductivity in polyurethane foam and glass microballoons

    SciTech Connect (OSTI)

    Hartman, E. Frederick; Zarick, Thomas Andrew; Sheridan, Timothy J.; Preston, Eric F.

    2014-06-01

    We performed measurements and analyses of the prompt radiation-induced conductivity (RIC) in thin samples of polyurethane foam and glass microballoon foam at the Little Mountain Medusa LINAC facility in Ogden, UT. The RIC coefficient was non-linear with dose rate for polyurethane foam; however, typical values at 1E11 rad(si)/s dose rate was measured as 0.8E-11 mho/m/rad/s for 5 lb./cu ft. foam and 0.3E-11 mho/m/rad/s for 10 lb./cu ft. density polyurethane foam. For encapsulated glass microballoons (GMB) the RIC coefficient was approximately 1E-15 mho/m/rad/s and was not a strong function of dose rate.

  17. Radiation-Induced Segregation and Phase Stability in Candidate Alloys for the Advanced Burner Reactor

    SciTech Connect (OSTI)

    Gary S. Was; Brian D. Wirth

    2011-05-29

    Major accomplishments of this project were the following: 1) Radiation induced depletion of Cr occurs in alloy D9, in agreement with that observed in austenitic alloys. 2) In F-M alloys, Cr enriches at PAG grain boundaries at low dose (<7 dpa) and at intermediate temperature (400C) and the magnitude of the enrichment decreases with temperature. 3) Cr enrichment decreases with dose, remaining enriched in alloy T91 up to 10 dpa, but changing to depletion above 3 dpa in HT9 and HCM12A. 4) Cr has a higher diffusivity than Fe by a vacancy mechanism and the corresponding atomic flux of Cr is larger than Fe in the opposite direction to the vacancy flux. 5) Cr concentration at grain boundaries decreases as a result of vacancy transport during electron or proton irradiation, consistent with Inverse Kirkendall models. 6) Inclusion of other point defect sinks into the KLMC simulation of vacancy-mediated diffusion only influences the results in the low temperature, recombination dominated regime, but does not change the conclusion that Cr depletes as a result of vacancy transport to the sink. 7) Cr segregation behavior is independent of Frenkel pair versus cascade production, as simulated for electron versus proton irradiation conditions, for the temperatures investigated. 8) The amount of Cr depletion at a simulated planar boundary with vacancy-mediated diffusion reaches an apparent saturation value by about 1 dpa, with the precise saturation concentration dependent on the ratio of Cr to Fe diffusivity. 9) Cr diffuses faster than Fe by an interstitial transport mechanism, and the corresponding atomic flux of Cr is much larger than Fe in the same direction as the interstitial flux. 10) Observed experimental and computational results show that the radiation induced segregation behavior of Cr is consistent with an Inverse Kirkendall mechanism.

  18. The Role of Platelet Factor 4 in Radiation-Induced Thrombocytopenia

    SciTech Connect (OSTI)

    Lambert, Michele P.; Xiao Liqing; Nguyen, Yvonne; Kowalska, M. Anna; Poncz, Mortimer

    2011-08-01

    Purpose: Factors affecting the severity of radiation-induced thrombocytopenia (RIT) are not well described. We address whether platelet factor 4 (PF4; a negative paracrine for megakaryopoiesis) affects platelet recovery postradiation. Methods and Materials: Using conditioned media from irradiated bone marrow (BM) cells from transgenic mice overexpressing human (h) PF4 (hPF4+), megakaryocyte colony formation was assessed in the presence of this conditioned media and PF4 blocking agents. In a model of radiation-induced thrombocytopenia, irradiated mice with varying PF4 expression levels were treated with anti-hPF4 and/or thrombopoietin (TPO), and platelet count recovery and survival were examined. Results: Conditioned media from irradiated BM from hPF4+ mice inhibited megakaryocyte colony formation, suggesting that PF4 is a negative paracrine released in RIT. Blocking with an anti-hPF4 antibody restored colony formation of BM grown in the presence of hPF4+ irradiated media, as did antibodies that block the megakaryocyte receptor for PF4, low-density lipoprotein receptor-related protein 1 (LRP1). Irradiated PF4 knockout mice had higher nadir platelet counts than irradiated hPF4+/knockout litter mates (651 vs. 328 x 106/mcL, p = 0.02) and recovered earlier (15 days vs. 22 days, respectively, p <0.02). When irradiated hPF4+ mice were treated with anti-hPF4 antibody and/or TPO, they showed less severe thrombocytopenia than untreated mice, with improved survival and time to platelet recovery, but no additive effect was seen. Conclusions: Our studies show that in RIT, damaged megakaryocytes release PF4 locally, inhibiting platelet recovery. Blocking PF4 enhances recovery while released PF4 from megakaryocytes limits TPO efficacy, potentially because of increased release of PF4 stimulated by TPO. The clinical value of blocking this negative paracrine pathway post-RIT remains to be determined.

  19. Reflection-induced spectral changes of the pulsed radiation emitted by a point source S. H. Wiersma,1

    E-Print Network [OSTI]

    Visser, Taco D.

    at hand, the primary wave field excited by the point source is a spherical wave. Its power densityReflection-induced spectral changes of the pulsed radiation emitted by a point source S. H. Wiersma of Information Technology and Systems, Delft University of Technology, Mekelweg 4, 2628 CD Delft, The Netherlands

  20. Spatiotemporal characterization of ionizing radiation induced DNA damage foci and their relation to chromatin organization

    E-Print Network [OSTI]

    Costes, Sylvain V

    2010-01-01

    germ cells and after low-dose gamma-radiation: relationshipsexposure to low doses of ionizing radiation. Mutat Res (after exposure to low doses of ionizing radiation. Mutat Res

  1. Amifostine, a radioprotectant agent, protects rat brain tissue lipids against ionizing radiation induced damage: An FTIR microspectroscopic imaging study

    SciTech Connect (OSTI)

    Cakmak G.; Miller L.; Zorlu, F.; Severcan, F.

    2012-03-03

    Amifostine is the only approved radioprotective agent by FDA for reducing the damaging effects of radiation on healthy tissues. In this study, the protective effect of amifostine against the damaging effects of ionizing radiation on the white matter (WM) and grey matter (GM) regions of the rat brain were investigated at molecular level. Sprague-Dawley rats, which were administered amifostine or not, were whole-body irradiated at a single dose of 800 cGy, decapitated after 24 h and the brain tissues of these rats were analyzed using Fourier transform infrared microspectroscopy (FTIRM). The results revealed that the total lipid content and CH{sub 2} groups of lipids decreased significantly and the carbonyl esters, olefinic=CH and CH{sub 3} groups of lipids increased significantly in the WM and GM after exposure to ionizing radiation, which could be interpreted as a result of lipid peroxidation. These changes were more prominent in the WM of the brain. The administration of amifostine before ionizing radiation inhibited the radiation-induced lipid peroxidation in the brain. In addition, this study indicated that FTIRM provides a novel approach for monitoring ionizing radiation induced-lipid peroxidation and obtaining different molecular ratio images can be used as biomarkers to detect lipid peroxidation in biological systems.

  2. Flavin-Induced Oligomerization in Escherichia coli Adaptive Response Protein AidB

    SciTech Connect (OSTI)

    Hamill, Michael J.; Jost, Marco; Wong, Cintyu; Elliott, Sean J.; Drennan, Catherine L. (MIT); (BU)

    2011-11-21

    The process known as 'adaptive response' allows Escherichia coli to respond to small doses of DNA-methylating agents by upregulating the expression of four proteins. While the role of three of these proteins in mitigating DNA damage is well understood, the function of AidB is less clear. Although AidB is a flavoprotein, no catalytic role has been established for the bound cofactor. Here we investigate the possibility that flavin plays a structural role in the assembly of the AidB tetramer. We report the generation and biophysical characterization of deflavinated AidB and of an AidB mutant that has greatly reduced affinity for flavin adenine dinucleotide (FAD). Using fluorescence quenching and analytical ultracentrifugation, we find that apo AidB has a high affinity for FAD, as indicated by an apparent dissociation constant of 402.1 {+-} 35.1 nM, and that binding of substoichiometric amounts of FAD triggers a transition in the AidB oligomeric state. In particular, deflavinated AidB is dimeric, whereas the addition of FAD yields a tetramer. We further investigate the dimerization and tetramerization interfaces of AidB by determining a 2.8 {angstrom} resolution crystal structure in space group P3{sub 2} that contains three intact tetramers in the asymmetric unit. Taken together, our findings provide strong evidence that FAD plays a structural role in the formation of tetrameric AidB.

  3. Biological effects in unirradiated human tissue induced by radiation damage up to 1 mm away

    E-Print Network [OSTI]

    Brenner, David Jonathan

    in extrapolating radiation risk estimates from epidemi- ologically accessible doses down to very low doses where) and for assessing the risk from a low-dose exposure to a carcinogen such as ionizing radiation, where only a small, New York, NY 10032; Radiation Biology Laboratory, Research and Environmental Surveillance, Radiation

  4. Detection and Repair of Ionizing Radiation-Induced DNA Double Strand Breaks: New Developments in Nonhomologous End Joining

    SciTech Connect (OSTI)

    Wang, Chen [Departments of Biochemistry and Molecular Biology and Oncology, and Southern Alberta Cancer Research Institute, University of Calgary, Calgary (Canada)] [Departments of Biochemistry and Molecular Biology and Oncology, and Southern Alberta Cancer Research Institute, University of Calgary, Calgary (Canada); Lees-Miller, Susan P., E-mail: leesmill@ucalgary.ca [Departments of Biochemistry and Molecular Biology and Oncology, and Southern Alberta Cancer Research Institute, University of Calgary, Calgary (Canada)

    2013-07-01

    DNA damage can occur as a result of endogenous metabolic reactions and replication stress or from exogenous sources such as radiation therapy and chemotherapy. DNA double strand breaks are the most cytotoxic form of DNA damage, and defects in their repair can result in genome instability, a hallmark of cancer. The major pathway for the repair of ionizing radiation-induced DSBs in human cells is nonhomologous end joining. Here we review recent advances on the mechanism of nonhomologous end joining, as well as new findings on its component proteins and regulation.

  5. Radiative observables for linearized gravity on asymptotically flat spacetimes and their boundary induced states

    SciTech Connect (OSTI)

    Benini, Marco Dappiaggi, Claudio; Murro, Simone

    2014-08-01

    We discuss the quantization of linearized gravity on globally hyperbolic, asymptotically flat, vacuum spacetimes, and the construction of distinguished states which are both of Hadamard form and invariant under the action of all bulk isometries. The procedure, we follow, consists of looking for a realization of the observables of the theory as a sub-algebra of an auxiliary, non-dynamical algebra constructed on future null infinity ??. The applicability of this scheme is tantamount to proving that a solution of the equations of motion for linearized gravity can be extended smoothly to ??. This has been claimed to be possible provided that a suitable gauge fixing condition, first written by Geroch and Xanthopoulos [Asymptotic simplicity is stable, J. Math. Phys. 19, 714 (1978)], is imposed. We review its definition critically, showing that there exists a previously unnoticed obstruction in its implementation leading us to introducing the concept of radiative observables. These constitute an algebra for which a Hadamard state induced from null infinity and invariant under the action of all spacetime isometries exists and it is explicitly constructed.

  6. Development of a robust modeling tool for radiation-induced segregation in austenitic stainless steels

    SciTech Connect (OSTI)

    Yang, Ying; Field, Kevin G; Allen, Todd R.; Busby, Jeremy T

    2015-09-01

    Irradiation-assisted stress corrosion cracking (IASCC) of austenitic stainless steels in Light Water Reactor (LWR) components has been linked to changes in grain boundary composition due to irradiation induced segregation (RIS). This work developed a robust RIS modeling tool to account for thermodynamics and kinetics of the atom and defect transportation under combined thermal and radiation conditions. The diffusion flux equations were based on the Perks model formulated through the linear theory of the thermodynamics of irreversible processes. Both cross and non-cross phenomenological diffusion coefficients in the flux equations were considered and correlated to tracer diffusion coefficients through Mannings relation. The preferential atomvacancy coupling was described by the mobility model, whereas the preferential atom-interstitial coupling was described by the interstitial binding model. The composition dependence of the thermodynamic factor was modeled using the CALPHAD approach. Detailed analysis on the diffusion fluxes near and at grain boundaries of irradiated austenitic stainless steels suggested the dominant diffusion mechanism for chromium and iron is via vacancy, while that for nickel can swing from the vacancy to the interstitial dominant mechanism. The diffusion flux in the vicinity of a grain boundary was found to be greatly influenced by the composition gradient formed from the transient state, leading to the oscillatory behavior of alloy compositions in this region. This work confirms that both vacancy and interstitial diffusion, and segregation itself, have important roles in determining the microchemistry of Fe, Cr, and Ni at irradiated grain boundaries in austenitic stainless steels.

  7. The effects of diet and ionizing radiation on azoxymethane induced colon carcinogenesis

    E-Print Network [OSTI]

    Mann, John Clifford

    2006-10-30

    The ability of ionizing radiation to enhance colon carcinogenesis and the role of diet in this process has not been documented. We hypothesized that radiation would enhance the formation of aberrant crypt foci, ACF, known ...

  8. SciFri AM: Mountain 04: Label-free Raman spectroscopy of single tumour cells detects early radiation-induced glycogen synthesis associated with increased radiation resistance

    SciTech Connect (OSTI)

    Matthews, Q; Lum, JJ; Isabelle, M; Harder, S; Jirasek, A; Brolo, AG

    2014-08-15

    Purpose: To use label-free Raman spectroscopy (RS) for early treatment monitoring of tumour cell radioresistance. Methods: Three human tumour cell lines, two radioresistant (H460, SF{sub 2} = 0.57 and MCF7, SF{sub 2} = 0.70) and one radiosensitive (LNCaP, SF{sub 2} = 0.36), were irradiated with single fractions of 2, 4, 6, 8 or 10 Gy. In additional experiments, H460 and MCF7 cells were irradiated under co-treatment with the anti-diabetic drug metformin, a known radiosensitizing agent. Treated and control cultures were analyzed with RS daily for 3 days post-treatment. Single-cell Raman spectra were acquired from 20 live cells per sample, and experiments were repeated in triplicate. The combined data sets were analyzed with principal component analysis using standard algorithms. Cells from each culture were also subjected to standard assays for viability, proliferation, cell cycle, and radiation clonogenic survival. Results: The radioresistant cells (H460, MCF7) exhibited a RS molecular radiation response signature, detectable as early as 1 day post-treatment, of which radiation-induced glycogen synthesis is a significant contributor. The radiosensitive cells (LNCaP) exhibited negligible glycogen synthesis. Co-treatment with metformin in MCF7 cells blocked glycogen synthesis, reduced viability and proliferation, and increased radiosensitivity. Conversely, metformin co-treatment in H460 cells did not produce these same effects; importantly, both radiation-induced synthesis of glycogen and radiosensitivity were unaffected. Conclusions: Label-free RS can detect early glycogen synthesis post-irradiation, a previously undocumented metabolic mechanism associated with tumour cell radioresistance that can be targeted to increase radiosensitivity. RS monitoring of intratumoral glycogen may provide new opportunities for personalized combined modality radiotherapy treatments.

  9. Radiation-Induced Carcinogenesis: Mechanistically Based Differences between Gamma-Rays and Neutrons, and

    E-Print Network [OSTI]

    Brenner, David Jonathan

    . For radiation doses which are sufficiently low to avoid substantial cell killing, sparsely ionizing radiation dose/dose rate. Sparsely ionizing radiation (e.g. c-rays) generally produces linear or upwardly curving dose responses at low doses, and the risk decreases when the dose rate is reduced (direct dose rate

  10. A Systems Genetic Approach to Identify Low Dose Radiation-Induced Lymphoma Susceptibility/DOE2013FinalReport

    SciTech Connect (OSTI)

    Balmain, Allan; Song, Ihn Young

    2013-05-15

    The ultimate goal of this project is to identify the combinations of genetic variants that confer an individual's susceptibility to the effects of low dose (0.1 Gy) gamma-radiation, in particular with regard to tumor development. In contrast to the known effects of high dose radiation in cancer induction, the responses to low dose radiation (defined as 0.1 Gy or less) are much less well understood, and have been proposed to involve a protective anti-tumor effect in some in vivo scientific models. These conflicting results confound attempts to develop predictive models of the risk of exposure to low dose radiation, particularly when combined with the strong effects of inherited genetic variants on both radiation effects and cancer susceptibility. We have used a ??Systems Genetics approach in mice that combines genetic background analysis with responses to low and high dose radiation, in order to develop insights that will allow us to reconcile these disparate observations. Using this comprehensive approach we have analyzed normal tissue gene expression (in this case the skin and thymus), together with the changes that take place in this gene expression architecture a) in response to low or high- dose radiation and b) during tumor development. Additionally, we have demonstrated that using our expression analysis approach in our genetically heterogeneous/defined radiation-induced tumor mouse models can uniquely identify genes and pathways relevant to human T-ALL, and uncover interactions between common genetic variants of genes which may lead to tumor susceptibility.

  11. Reproductive Status at First Diagnosis Influences Risk of Radiation-Induced Second Primary Contralateral Breast Cancer in the WECARE Study

    SciTech Connect (OSTI)

    Brooks, Jennifer D.; Boice, John D.; Stovall, Marilyn; Reiner, Anne S.; Bernstein, Leslie; John, Esther M.; Lynch, Charles F.; Mellemkjaer, Lene; Knight, Julia A.; Thomas, Duncan C.; Haile, Robert W.; Smith, Susan A.; Capanu, Marinela; Bernstein, Jonine L.; Shore, Roy E.; Radiation Effects Research Foundation, Hiroshima

    2012-11-15

    Purpose: Our study examined whether reproductive and hormonal factors before, at the time of, or after radiation treatment for a first primary breast cancer modify the risk of radiation-induced second primary breast cancer. Methods and Materials: The Women's Environmental, Cancer and Radiation Epidemiology (WECARE) Study is a multicenter, population-based study of 708 women (cases) with asynchronous contralateral breast cancer (CBC) and 1399 women (controls) with unilateral breast cancer. Radiotherapy (RT) records, coupled with anthropomorphic phantom simulations, were used to estimate quadrant-specific radiation dose to the contralateral breast for each patient. Rate ratios (RR) and 95% confidence intervals (CI) were computed to assess the relationship between reproductive factors and risk of CBC. Results: Women who were nulliparous at diagnosis and exposed to {>=}1 Gy to the contralateral breast had a greater risk for CBC than did matched unexposed nulliparous women (RR = 2.2; 95% CI, 1.2-4.0). No increased risk was seen in RT-exposed parous women (RR = 1.1; 95% CI, 0.8-1.4). Women treated with RT who later became pregnant (8 cases and 9 controls) had a greater risk for CBC (RR = 6.0; 95% CI, 1.3-28.4) than unexposed women (4 cases and 7 controls) who also became pregnant. The association of radiation with risk of CBC did not vary by number of pregnancies, history of breastfeeding, or menopausal status at the time of first breast cancer diagnosis. Conclusion: Nulliparous women treated with RT were at an increased risk for CBC. Although based on small numbers, women who become pregnant after first diagnosis also seem to be at an increased risk for radiation-induced CBC.

  12. Radiatively Induced Type II seesaw and Vector-like 5/3 Charge Quarks

    E-Print Network [OSTI]

    R. Franceschini; R. N. Mohapatra

    2013-06-26

    Understanding small neutrino masses in type II seesaw models with TeV scale SM triplet Higgs bosons requires that its coupling with the standard model Higgs doublet H be dialed down to be order eV to KeV, which is a fine-tuning by a factor of $10^{-11}-10^{-8}$ with respect to the weak scale. We present a SUSY extension of the type II seesaw model where this dimensionful small coupling is radiatively induced, thus making its smallness natural. This model has an exotic vector-like quark doublet which contains a quark X with electric charge 5/3 and a top partner t'. We discuss in details the phenomenology of the model paying special attention to the consequences of the interactions of the the exotic heavy quarks and the scalars of the model. Implications for neutrinoless double beta decay and for the LHC experiments are discussed in detail. Remarkably, in this model both the seesaw triplet and the heavy quarks can manifest at colliders in a host of different signatures, including some that significantly differ from those of the minimal models. Depending on the choice of the hierarchy of couplings, the decay of the heavy quarks and of the seesaw triplet may be subject to bounds that can be tighter or looser than the bounds from standard LHC searches. Furthermore we point out a new short-distance contribution to neutrinoless double beta decay mediated by the simultaneous propagation of the type II triplet and exotic fermions. Remarkably this contribution to the neutrinoless double beta decay is parametrically quite independent from the scale of the generated neutrino mass.

  13. A Phase II Study of Submandibular Gland Transfer Prior to Radiation for Prevention of Radiation-induced Xerostomia in Head-and-Neck Cancer (RTOG 0244)

    SciTech Connect (OSTI)

    Jha, Naresh, E-mail: naresh.jha@albertahealthservices.ca [University of Alberta, Cross Cancer Institute, Edmonton, Alberta (Canada)] [University of Alberta, Cross Cancer Institute, Edmonton, Alberta (Canada); Harris, Jonathan [Radiation Therapy Oncology Group Statistical Center, Philadelphia, Pennsylvania (United States)] [Radiation Therapy Oncology Group Statistical Center, Philadelphia, Pennsylvania (United States); Seikaly, Hadi [University of Alberta, Edmonton, Alberta (Canada)] [University of Alberta, Edmonton, Alberta (Canada); Jacobs, John R. [Wayne State University School of Medicine, Detroit, Michigan (United States)] [Wayne State University School of Medicine, Detroit, Michigan (United States); McEwan, A.J.B. [University of Alberta, Cross Cancer Institute, Edmonton, Alberta (Canada)] [University of Alberta, Cross Cancer Institute, Edmonton, Alberta (Canada); Robbins, K. Thomas [St. John's Hospital Cancer Institute, Springfield, Illinois (United States)] [St. John's Hospital Cancer Institute, Springfield, Illinois (United States); Grecula, John [Ohio State University Medical Center, Columbus, Ohio (United States)] [Ohio State University Medical Center, Columbus, Ohio (United States); Sharma, Anand K. [Medical University of South Carolina, Charleston, South Carolina (United States)] [Medical University of South Carolina, Charleston, South Carolina (United States); Ang, K. Kian [University of Texas MD Anderson Cancer Center, Houston, Texas (United States)] [University of Texas MD Anderson Cancer Center, Houston, Texas (United States)

    2012-10-01

    Purpose: We report the results of a phase II study to determine the reproducibility of a submandibular salivary gland transfer (SGT) surgical technique for prevention of radiation (XRT)-induced xerostomia in a multi-institutional setting and to assess severity of xerostomia. Methods and Materials: Eligible patients had surgery for primary, neck dissection, and SGT, followed by XRT, during which the transferred salivary gland was shielded. Intensity modulated radiation therapy, amifostine, and pilocarpine were not allowed, but postoperative chemotherapy was allowed. Each operation was reviewed by 2 reviewers and radiation by 1 reviewer. If 13 or more (of 43) were 'not per protocol,' then the technique would be considered not reproducible as per study design. The secondary endpoint was the rate of acute xerostomia, grade 2 or higher, and a rate of {<=}51% was acceptable. Results: Forty-four of the total 49 patients were analyzable: male (81.8%), oropharynx (63.6%), stage IV (61.4%), median age 56.5 years. SGT was 'per protocol' or within acceptable variation in 34 patients (77.3%) and XRT in 79.5%. Nine patients (20.9%) developed grade 2 acute xerostomia; 2 had grade 0-1 xerostomia (4.7%) but started on amifostine/pilocarpine. Treatment for these 11 patients (25.6%) was considered a failure for the xerostomia endpoint. Thirteen patients died; median follow-up for 31 surviving patients was 2.9 years. Two-year overall and disease-free survival rates were 76.4% and 71.7%, respectively. Conclusions: The technique of submandibular SGT is reproducible in a multicenter setting. Seventy-four percent of patients were prevented from XRT-induced acute xerostomia.

  14. Low Dose Radiation-Induced Genome and Epigenome Instability Symposium and Epigenetic Mechanisms, DNA Repair, and Chromatin Symposium at the EMS 2008 Annual Meeting - October 2008

    SciTech Connect (OSTI)

    Morgan, William F.; Kovalchuk, Olga; Dolinoy, Dana C.; Dubrova, Yuri E.; Coleman, Matthew A.; Schr, Primo; Pogribny, Igor; Hendzel, Michael

    2010-02-19

    The Low Dose Radiation Symposium thoughtfully addressed ionizing radiation non-mutational but transmissable alterations in surviving cells. Deregulation of epigenetic processes has been strongly implicated in carcinogenesis, and there is increasing realization that a significant fraction of non-targeted and adaptive mechanisms in response to ionizing radiation are likely to be epigenetic in nature. Much remains to be learned about how chromatin and epigenetic regulators affect responses to low doses of radiation, and how low dose radiation impacts other epigenetic processes. The Epigenetic Mechanisms Symposium focused on on epigenetic mechanisms and their interplay with DNA repair and chromatin changes. Addressing the fact that the most well understood mediators of epigenetic regulation are histone modifications and DNA methylation. Low levels of radiation can lead to changes in the methylation status of certain gene promoters and the expression of DNA methyltransferases, However, epigenetic regulation can also involve changes in higher order chromosome structure.

  15. Effects of UVB Radiation & Herbivory on Induced Resistance Traits in Datura Wrightii

    E-Print Network [OSTI]

    McNamara, Sean

    2015-01-01

    absorbing UV radiation (Beggs et al. 1985, Li et al. 1993,project.org/package-lme4 Beggs, C.J. , Stolzer-Jehle, A. , &

  16. Formation mechanisms of precursors of radiation-induced color centers during fabrication of silica optical fiber preform

    SciTech Connect (OSTI)

    Tomashuk, A. L.; Zabezhailov, M. O.

    2011-04-15

    Samples in the form of transverse slices of rods and optical fiber preforms made from the high-hydroxyl KU-1 and low-hydroxyl KS-4V silica by the plasma outside deposition (POD) method are {gamma}-irradiated to a dose of {approx}1 MGy (SiO{sub 2}). Next, the radial dependences of the radiation-induced nonbridging oxygen hole center (NBOHC) and E'-center (three-coordinated silicon) in the samples are constructed by measuring the amplitudes of their 4.8 and 5.8 eV absorption bands, respectively. Based on the analysis of these radial dependences and considering the temperature and duration of the preirradiation heat treatment of the rods and preforms at the POD-installation, we determine the ratio of the oscillator strengths of the above bands and the microscopic thermoinduced processes occurring during preform fabrication and producing precursors of the radiation-induced NBOHC and E'-center. These processes are found to be associated with the escape of either H{sub 2} or H{sub 2}O from neighboring hydroxyl groups, and, therefore, can occur in high-hydroxyl silica only. It is concluded that enhancement of the radiation resistance of high-hydroxyl silica optical fibers requires decreasing the temperature and duration of the preform fabrication process, in particular, changing from the POD-technology to the low-temperature plasmachemical vapor deposition (PCVD) or surface PCVD (SPCVD)-technology.

  17. The Balance Between Initiation and Promotion in Radiation-Induced Murine Carcinogenesis

    E-Print Network [OSTI]

    Brenner, David Jonathan

    becomes important at older ages. g 2010 by Radiation Research Society INTRODUCTION Most mathematical of the shape and magnitude of the initial dose response over the long period after radiation exposure before). Some of the model parameters were obtained from fitting radiogenic risks at compar- atively low doses

  18. Effects of exogenous carbon monoxide on radiation-induced bystander effect in zebrafish embryos in vivo

    E-Print Network [OSTI]

    Yu, Peter K.N.

    that the dose-response of radiation in the low-dose regime deviated from the LNT model. A notable example radiation are linearly proportional to the absorbed dose, evidence accumulated in the past decades showed as a pharmaceutical agent to release a low dose of exogenous carbon monoxide (CO) to attenuate the effect on bystander

  19. Ab Initio and Kinetic Rate Theory Modeling of 316SS with Oversized Solute Additions on Radiation-Induced Segregation

    SciTech Connect (OSTI)

    Hackett, Micah J.; Was, Gary S.

    2008-07-01

    Deleterious effects of radiation in nuclear reactor systems cause material degradation and the potential for component failure. Radiation damage is fundamentally due to freely migrating point defects produced in collision cascades. A reduction in the freely migrating point defect population should, then, reduce radiation damage and increase component lifetime. The addition of oversized solute atoms such as Zr or Hf to 316SS, a common structural material in reactors, is expected to reduce point defect population through a trapping mechanism that enhances recombination. The mechanism, however, requires a strong binding energy between the oversized solute atom and vacancies in order for the mechanism to significantly reduce the defect population. Experimental measurements of this binding energy are unavailable, but can be determined with atomistic calculations. Ab initio methods are used here to determine binding energies and atomic volumes of either Hf or Zr oversized solutes with vacancies in a face-centered cubic Fe matrix. The binding energies are then used to parameterize a kinetic rate-theory model, which is used here to calculate radiation-induced segregation (RIS). The calculated values of RIS are then compared to experimental measurements to benchmark the calculations and offer insight into the proposed point defect trapping mechanism. (author)

  20. Radiation-induced instability of MnS precipitates and its possible consequences on irradiation-induced stress corrosion cracking of austenitic stainless steels

    SciTech Connect (OSTI)

    Chung, H.M.; Sanecki, J.E.; Garner, F.A.

    1996-12-01

    Irradiation-assisted stress corrosion cracking (IASCC) is a significant materials issue for the light water reactor (LWR) industry and may also pose a problem for fusion power reactors that will use water as coolant. A new metallurgical process is proposed that involves the radiation-induced release into solution of minor impurity elements not usually thought to participate in IASCC. MnS-type precipitates, which contain most of the sulfur in stainless steels, are thought to be unstable under irradiation. First, Mn transmutes strongly to Fe in thermalized neutron spectra. Second, cascade-induced disordering and the inverse Kirkendall effect operating at the incoherent interfaces of MnS precipitates are thought to act as a pump to export Mn from the precipitate into the alloy matrix. Both of these processes will most likely allow sulfur, which is known to exert a deleterious influence on intergranular cracking, to re-enter the matrix. To test this hypothesis, compositions of MnS-type precipitates contained in several unirradiated and irradiated heats of Type 304, 316, and 348 stainless steels (SSs) were analyzed by Auger electron spectroscopy. Evidence is presented that shows a progressive compositional modification of MnS precipitates as exposure to neutrons increases in boiling water reactors. As the fluence increases, the Mn level in MnS decreases, whereas the Fe level increases. The S level also decreases relative to the combined level of Mn and Fe. MnS precipitates were also found to be a reservoir of other deleterious impurities such as F and O which could be also released due to radiation-induced instability of the precipitates.

  1. SU-E-J-17: A Study of Accelerator-Induced Cerenkov Radiation as a Beam Diagnostic and Dosimetry Tool

    SciTech Connect (OSTI)

    Bateman, F; Tosh, R [NIST, Gaithersburg, MD (United States)

    2014-06-01

    Purpose: To investigate accelerator-induced Cerenkov radiation imaging as a possible beam diagnostic and medical dosimetry tool. Methods: Cerenkov emission produced by clinical accelerator beams in a water phantom was imaged using a camera system comprised of a high-sensitivity thermoelectrically-cooled CCD camera coupled to a large aperture (f/0.75) objective lens with 16:1 magnification. This large format lens allows a significant amount of the available Cerenkov light to be collected and focused onto the CCD camera to form the image. Preliminary images, obtained with 6 MV photon beams, used an unshielded camera mounted horizontally with the beam normal to the water surface, and confirmed the detection of Cerenkov radiation. Several improvements were subsequently made including the addition of radiation shielding around the camera, and altering of the beam and camera angles to give a more favorable geometry for Cerenkov light collection. A detailed study was then undertaken over a range of electron and photon beam energies and dose rates to investigate the possibility of using this technique for beam diagnostics and dosimetry. Results: A series of images were obtained at a fixed dose rate over a range of electron energies from 6 to 20 MeV. The location of maximum intensity was found to vary linearly with the energy of the beam. A linear relationship was also found between the light observed from a fixed point on the central axis and the dose rate for both photon and electron beams. Conclusion: We have found that the analysis of images of beam-induced Cerenkov light in a water phantom has potential for use as a beam diagnostic and medical dosimetry tool. Our future goals include the calibration of the light output in terms of radiation dose and development of a tomographic system for 3D Cerenkov imaging in water phantoms and other media.

  2. microRNA Alterations Driving Acute and Late Stages of Radiation-Induced Fibrosis in a Murine Skin Model

    SciTech Connect (OSTI)

    Simone, Brittany A.; Ly, David; Savage, Jason E.; Hewitt, Stephen M.; Dan, Tu D.; Ylaya, Kris; Shankavaram, Uma; Lim, Meng; Jin, Lianjin; Camphausen, Kevin; Mitchell, James B.; Simone, Nicole L.

    2014-09-01

    Purpose: Although ionizing radiation is critical in treating cancer, radiation-induced fibrosis (RIF) can have a devastating impact on patients' quality of life. The molecular changes leading to radiation-induced fibrosis must be elucidated so that novel treatments can be designed. Methods and Materials: To determine whether microRNAs (miRs) could be responsible for RIF, the fibrotic process was induced in the right hind legs of 9-week old CH3 mice by a single-fraction dose of irradiation to 35Gy, and the left leg served as an unirradiated control. Fibrosis was quantified by measurements of leg length compared with control leg length. By 120days after irradiation, the irradiated legs were 20% (P=.013) shorter on average than were the control legs. Results: Tissue analysis was done on muscle, skin, and subcutaneous tissue from irradiated and control legs. Fibrosis was noted on both gross and histologic examination by use of a pentachrome stain. Microarrays were performed at various times after irradiation, including 7days, 14days, 50days, 90days, and 120days after irradiation. miR-15a, miR-21, miR-30a, and miR-34a were the miRs with the most significant alteration by array with miR-34a, proving most significant on confirmation by reverse transcriptase polymerase chain reaction, c-Met, a known effector of fibrosis and downstream molecule of miR-34a, was evaluated by use of 2cell lines: HCT116 and 1522. The cell lines were exposed to various stressors to induce miR changes, specifically ionizing radiation. Additionally, invitro transfections with pre-miRs and anti-miRs confirmed the relationship of miR-34a and c-Met. Conclusions: Our data demonstrate an inverse relationship with miR-34a and c-Met; the upregulation of miR-34a in RIF causes inhibition of c-Met production. miRs may play a role in RIF; in particular, miR-34a should be investigated as a potential target to prevent or treat this devastating side effect of irradiation.

  3. Adaptors for radiation detectors

    DOE Patents [OSTI]

    Livesay, Ronald Jason

    2014-04-22

    Described herein are adaptors and other devices for radiation detectors that can be used to make accurate spectral measurements of both small and large bulk sources of radioactivity, such as building structures, soils, vessels, large equipment, and liquid bodies. Some exemplary devices comprise an adaptor for a radiation detector, wherein the adaptor can be configured to collimate radiation passing through the adapter from an external radiation source to the radiation detector and the adaptor can be configured to enclose a radiation source within the adapter to allow the radiation detector to measure radiation emitted from the enclosed radiation source.

  4. Adaptors for radiation detectors

    DOE Patents [OSTI]

    Livesay, Ronald Jason

    2015-07-28

    Described herein are adaptors and other devices for radiation detectors that can be used to make accurate spectral measurements of both small and large bulk sources of radioactivity, such as building structures, soils, vessels, large equipment, and liquid bodies. Some exemplary devices comprise an adaptor for a radiation detector, wherein the adaptor can be configured to collimate radiation passing through the adapter from an external radiation source to the radiation detector and the adaptor can be configured to enclose a radiation source within the adapter to allow the radiation detector to measure radiation emitted from the enclosed radiation source.

  5. LET dependence of radiation-induced bystander effects using human prostate tumor cells

    E-Print Network [OSTI]

    Anzenberg, Vered

    2008-01-01

    In the past fifteen years, evidence provided by many independent research groups have indicated higher numbers of cells exhibiting damage than expected based on the number of cells traversed by the radiation. This phenomenon ...

  6. Space radiation-induced bystander signaling in 2D and 3D skin tissue models

    E-Print Network [OSTI]

    Lumpkins, Sarah B

    2012-01-01

    Space radiation poses a significant hazard to astronauts on long-duration missions, and the low fluences of charged particles characteristic of this field suggest that bystander effects, the phenomenon in which a greater ...

  7. 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

    2014-06-01

    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.

  8. Novel detection methods for radiation-induced electron-hole pairs.

    SciTech Connect (OSTI)

    Nordquist, Christopher Daniel; Cich, Michael Joseph; Vawter, Gregory Allen; Derzon, Mark Steven; Martinez, Marino John

    2010-09-01

    Most common ionizing radiation detectors typically rely on one of two general methods: collection of charge generated by the radiation, or collection of light produced by recombination of excited species. Substantial efforts have been made to improve the performance of materials used in these types of detectors, e.g. to raise the operating temperature, to improve the energy resolution, timing or tracking ability. However, regardless of the material used, all these detectors are limited in performance by statistical variation in the collection efficiency, for charge or photons. We examine three alternative schemes for detecting ionizing radiation that do not rely on traditional direct collection of the carriers or photons produced by the radiation. The first method detects refractive index changes in a resonator structure. The second looks at alternative means to sense the chemical changes caused by radiation on a scintillator-type material. The final method examines the possibilities of sensing the perturbation caused by radiation on the transmission of a RF transmission line structure. Aspects of the feasibility of each approach are examined and recommendations made for further work.

  9. DOE contractors' workshop: Cellular and molecular aspects of radiation induced DNA damage and repair

    SciTech Connect (OSTI)

    Not Available

    1987-01-01

    For four decades the US Department of Energy and its predecessors have been the lead federal agency in supporting radiation biology research. Over the years emphasis in this program has gradually shifted from dose-effect studies on animals to research on the effects of radiations of various qualities on cells and molecules. Mechanistic studies on the action of radiation at the subcellular level are few in number and there is a need for more research in this area if we are to gain a better understanding of how radiation affects living cells. The intent of this workshop was to bring together DOE contractors and grantees who are investigating the effects of radiation at the cellular and molecular levels. The aims were to foster the exchange of information on research projects and experimental results, promote collaborative research efforts, and obtain an overview of research currently supported by the Health Effects Research Division of the Office of Health and Environmental Research. The latter is needed by the Office for program planning purposes. This report on the workshop which took place in Albuquerque, New Mexico on March 10-11, 1987, includes an overview with future research recommendations, extended abstracts of the plenary presentations, shorter abstracts of each poster presentation, a workshop agenda and the names and addresses of the attendees.

  10. The influence of TRP53 in the dose response of radiation-induced apoptosis, DNA repair and genomic stability in murine haematopoietic cells

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

    Lemon, Jennifer A.; Taylor, Kristina; Verdecchia, Kyle; Phan, Nghi; Boreham, Douglas R.

    2014-01-01

    Apoptotic and DNA damage endpoints are frequently used as surrogate markers of cancer risk, and have been well-studied in the Trp53+/- mouse model. We report the effect of differing Trp53 gene status on the dose response of ionizing radiation exposures (0.01-2 Gy), with the unique perspective of determining if effects of gene status remain at extended time points. Here we report no difference in the dose response for radiation-induced DNA double-strand breaks in bone marrow and genomic instability (MN-RET levels) in peripheral blood, between wild-type (Trp53+/+) and heterozygous (Trp53+/-) mice. The dose response for Trp53+/+ mice showed higher initial levelsmoreof radiation-induced lymphocyte apoptosis relative to Trp53+/- between 0 and 1 Gy. Although this trend was observed up to 12 hours post-irradiation, both genotypes ultimately reached the same level of apoptosis at 14 hours, suggesting the importance of late-onset p53-independent apoptotic responses in this mouse model. Expected radiation-induced G1 cell cycle delay was observed in Trp53+/+ but not Trp53+/-. Although p53 has an important role in cancer risk, we have shown its influence on radiation dose response can be temporally variable. This research highlights the importance of caution when using haematopoietic endpoints as surrogates to extrapolate radiation-induced cancer risk estimation.less

  11. Process for producing radiation-induced self-terminating protective coatings on a substrate

    DOE Patents [OSTI]

    Klebanoff, Leonard E. (Dublin, CA)

    2001-01-01

    A gas and radiation are used to produce a protective coating that is substantially void-free on the molecular scale, self-terminating, and degradation resistant. The process can be used to deposit very thin (.apprxeq.5-20 .ANG.) coatings on critical surfaces needing protection from degradative processes including, corrosion and contamination.

  12. TGF-.beta. antagonists as mitigators of radiation-induced tissue damage

    DOE Patents [OSTI]

    Barcellos-Hoff, Mary H. (Oakland, CA)

    1997-01-01

    A method for treating tissue damage caused by radiation is described by use of a TGF-.beta. antagonist, such as an anti-TGF-.beta. antibody or a TGF-.beta. latency associated protein. It is administered not more than a week after exposure, and is particularly useful in mitigating the side effects of breast cancer therapy.

  13. TGF-{beta} antagonists as mitigators of radiation-induced tissue damage

    DOE Patents [OSTI]

    Barcellos-Hoff, M.H.

    1997-04-01

    A method for treating tissue damage caused by radiation is described by use of a TGF-{beta} antagonist, such as an anti-TGF-{beta} antibody or a TGF-{beta} latency associated protein. It is administered not more than a week after exposure, and is particularly useful in mitigating the side effects of breast cancer therapy.

  14. Ionizing radiation predisposes non-malignant human mammary epithelial cells to undergo TGF beta-induced epithelial to mesenchymal transition

    E-Print Network [OSTI]

    2007-01-01

    Health Effects; the Low Dose Radiation Program of the DOElong-term, low-dose ionizing radiation exposure in humans.

  15. An Atlas-Based Electron Density Mapping Method for Magnetic Resonance Imaging (MRI)-Alone Treatment Planning and Adaptive MRI-Based Prostate Radiation Therapy

    SciTech Connect (OSTI)

    Dowling, Jason A., E-mail: jason.dowling@csiro.au [Australian e-Health Research Center, CSIRO ICT Commonwealth Scientific and Industrial Research Organisation Information and Communication Technologies Centre, Queensland (Australia); Lambert, Jonathan [Calvary Mater Newcastle Hospital, New South Wales (Australia); University of Newcastle, New South Wales (Australia); Parker, Joel [Calvary Mater Newcastle Hospital, New South Wales (Australia); Salvado, Olivier; Fripp, Jurgen [Australian e-Health Research Center, CSIRO ICT Commonwealth Scientific and Industrial Research Organisation Information and Communication Technologies Centre, Queensland (Australia); Capp, Anne; Wratten, Chris; Denham, James W.; Greer, Peter B. [Calvary Mater Newcastle Hospital, New South Wales (Australia); University of Newcastle, New South Wales (Australia)

    2012-05-01

    Purpose: Prostate radiation therapy dose planning directly on magnetic resonance imaging (MRI) scans would reduce costs and uncertainties due to multimodality image registration. Adaptive planning using a combined MRI-linear accelerator approach will also require dose calculations to be performed using MRI data. The aim of this work was to develop an atlas-based method to map realistic electron densities to MRI scans for dose calculations and digitally reconstructed radiograph (DRR) generation. Methods and Materials: Whole-pelvis MRI and CT scan data were collected from 39 prostate patients. Scans from 2 patients showed significantly different anatomy from that of the remaining patient population, and these patients were excluded. A whole-pelvis MRI atlas was generated based on the manually delineated MRI scans. In addition, a conjugate electron-density atlas was generated from the coregistered computed tomography (CT)-MRI scans. Pseudo-CT scans for each patient were automatically generated by global and nonrigid registration of the MRI atlas to the patient MRI scan, followed by application of the same transformations to the electron-density atlas. Comparisons were made between organ segmentations by using the Dice similarity coefficient (DSC) and point dose calculations for 26 patients on planning CT and pseudo-CT scans. Results: The agreement between pseudo-CT and planning CT was quantified by differences in the point dose at isocenter and distance to agreement in corresponding voxels. Dose differences were found to be less than 2%. Chi-squared values indicated that the planning CT and pseudo-CT dose distributions were equivalent. No significant differences (p > 0.9) were found between CT and pseudo-CT Hounsfield units for organs of interest. Mean {+-} standard deviation DSC scores for the atlas-based segmentation of the pelvic bones were 0.79 {+-} 0.12, 0.70 {+-} 0.14 for the prostate, 0.64 {+-} 0.16 for the bladder, and 0.63 {+-} 0.16 for the rectum. Conclusions: The electron-density atlas method provides the ability to automatically define organs and map realistic electron densities to MRI scans for radiotherapy dose planning and DRR generation. This method provides the necessary tools for MRI-alone treatment planning and adaptive MRI-based prostate radiation therapy.

  16. Spark-induced radiation from hydrogen or deuterium-loaded palladium

    SciTech Connect (OSTI)

    Klema, E.D.; Iseler, G.W.

    1996-09-01

    Three sets of experiments were conducted to investigate the radiation produced by spark discharge on (a) oxidized palladium samples, (b) oxidized palladium samples loaded with hydrogen, and (c) oxidized palladium samples loaded with deuterium. In the first set, no radiation was measured above background; in the second set, 24-keV X rays were observed, and in the third set, 17-keV X rays were produced. The intensities of the hydrogen X rays were measured over a period of 12 days. During this time, the daily fluctuations overshadowed any long-term variation that might be present. The deuterium X rays were followed over a period of 26 weeks. Again, the intensities fluctuated with time, obscuring the long-term trend; in one case, there was a 40% change from one day to the next. 3 refs.

  17. Norathyriol Suppresses Skin Cancers Induced by Solar Ultraviolet Radiation by Targeting ERK Kinases

    SciTech Connect (OSTI)

    Li, Jixia; Malakhova, Margarita; Mottamal, Madhusoodanan; Reddy, Kanamata; Kurinov, Igor; Carper, Andria; Langfald, Alyssa; Oi, Naomi; Kim, Myoung Ok; Zhu, Feng; Sosa, Carlos P.; Zhou, Keyuan; Bode, Ann M.; Dong, Zigang

    2012-06-27

    Ultraviolet (UV) irradiation is the leading factor in the development of skin cancer, prompting great interest in chemopreventive agents for this disease. In this study, we report the discovery of norathyriol, a plant-derived chemopreventive compound identified through an in silico virtual screening of the Chinese Medicine Library. Norathyriol is a metabolite of mangiferin found in mango, Hypericum elegans, and Tripterospermum lanceolatum and is known to have anticancer activity. Mechanistic investigations determined that norathyriol acted as an inhibitor of extracellular signal-regulated kinase (ERK)1/2 activity to attenuate UVB-induced phosphorylation in mitogen-activated protein kinases signaling cascades. We confirmed the direct and specific binding of norathyriol with ERK2 through a cocrystal structural analysis. The xanthone moiety in norathyriol acted as an adenine mimetic to anchor the compound by hydrogen bonds to the hinge region of the protein ATP-binding site on ERK2. Norathyriol inhibited in vitro cell growth in mouse skin epidermal JB6 P+ cells at the level of G{sub 2}-M phase arrest. In mouse skin tumorigenesis assays, norathyriol significantly suppressed solar UV-induced skin carcinogenesis. Further analysis indicated that norathyriol mediates its chemopreventive activity by inhibiting the ERK-dependent activity of transcriptional factors AP-1 and NF-{kappa}B during UV-induced skin carcinogenesis. Taken together, our results identify norathyriol as a safe new chemopreventive agent that is highly effective against development of UV-induced skin cancer.

  18. Radiation-induced risk of resettling Bikini atoll. Final report, November 7, 1981-May 28, 1982

    SciTech Connect (OSTI)

    Kohn, H.I.; Dreyer, N.A.

    1982-01-01

    The Department of Energy (DOE) has concluded that the Bikini atoll is unsafe for resettlement. In response to the Bikinians' request for an independent review, we have examined the following DOE findings: (a) radionuclide contamination of Eneu and Bikini Islands, (b) radiation dosage to those who might resettle the islands, and (c) risks to the health of such settlers. We are in practical agreement with the DOE estimates. Resettlement of either island in 1983 would lead to a range of annual or 30-year cumulative doses that exceed the Federal Radiation Council (FRC) guides for the general population, but not those for occupation exposure. By 2013 resettlement of Eneu probably would be permissible. The principal source of radiation dose is local food, especially coconut, owing to contamination of the soil by cesium-137. A precise estimate of dose is impossible. The availability of imported foods would lessen local food consumption, but not sufficiently to meet the FRC guides for the general population. The 30-year cumulative index dose is 61 (25-122) rem for Bikini, and about 8 (3-16) rem for Eneu.

  19. Analysis of single-event upset of magnetic tunnel junction used in spintronic circuits caused by radiation-induced current

    SciTech Connect (OSTI)

    Sakimura, N.; Nebashi, R.; Sugibayashi, T.; Natsui, M.; Hanyu, T.; Ohno, H.

    2014-05-07

    This paper describes the possibility of a switching upset of a magnetic tunnel junction (MTJ) caused by a terrestrial radiation-induced single-event-upset (SEU) current in spintronic integrated circuits. The current waveforms were simulated by using a 3-D device simulator in a basic circuit including MTJs designed using 90-nm CMOS parameters and design rules. The waveforms have a 400?-?A peak and a 200-ps elapsed time when neutron particles with a linear energy transfer value of 14?MeV cm{sup 2}/mg enter the silicon surface. The authors also found that the SEU current may cause soft errors with a probability of more than 10{sup ?12} per event, which was obtained by approximate solution of the ordinary differential equation of switching probability when the intrinsic critical current (I{sub C0}) became less than 30??A.

  20. A physical model of the photo- and radiation-induced degradation of ytterbium-doped silica optical fibres

    SciTech Connect (OSTI)

    Mady, Franck Duchez, Jean-Bernard Mebrouk, Yasmine Benabdesselam, Mourad

    2014-10-21

    We propose a model to describe the photo- or/and the radiation-induced darkening of ytterbium-doped silica optical fibers. This model accounts for the well-established experimental features of photo-darkening. Degradation behaviors predicted for fibers pumped in harsh environments are also fully confirmed by experimental data reported in the work by Duchez et al. (this proceeding), which gives a detailed characterization of the interplay between the effects of the pump and those of a superimposed ionizing irradiation (actual operation conditions in space-based applications for instance). In particular, dependences of the darkening build-up on the pump power, the total ionizing dose and the dose rate are all correctly reproduced. The presented model is a sufficient one, including the minimal physical ingredients required to reproduce experimental features. Refinements could be proposed to improve, e.g., quantitative kinetics.

  1. Plasma induced DNA damage: Comparison with the effects of ionizing radiation

    SciTech Connect (OSTI)

    Lazovi?, S.; Maleti?, D.; Pua?, N.; Malovi?, G.; Petrovi?, Z. Lj.; Leskovac, A.; Filipovi?, J.; Joksi?, G.

    2014-09-22

    We use human primary fibroblasts for comparing plasma and gamma rays induced DNA damage. In both cases, DNA strand breaks occur, but of fundamentally different nature. Unlike gamma exposure, contact with plasma predominantly leads to single strand breaks and base-damages, while double strand breaks are mainly consequence of the cell repair mechanisms. Different cell signaling mechanisms are detected confirming this (ataxia telangiectasia mutated - ATM and ataxia telangiectasia and Rad3 related - ATR, respectively). The effective plasma doses can be tuned to match the typical therapeutic doses of 2?Gy. Tailoring the effective dose through plasma power and duration of the treatment enables safety precautions mainly by inducing apoptosis and consequently reduced frequency of micronuclei.

  2. Radiation-Induced Liver Fibrosis Is Mitigated by Gene Therapy Inhibiting Transforming Growth Factor-{beta} Signaling in the Rat

    SciTech Connect (OSTI)

    Du Shisuo; Qiang Ming [Department of Radiation Oncology, Zhongshan Hospital, Fudan University, Shanghai 200032 (China); Zeng Zhaochong, E-mail: zeng.zhaochong@zs-hospital.sh.c [Department of Radiation Oncology, Zhongshan Hospital, Fudan University, Shanghai 200032 (China); Zhou Jian [Liver Cancer Institute, Zhongshan Hospital, Fudan University, Shanghai 200032 (China); Tan Yunshan [Department of Pathology, Zhongshan Hospital, Fudan University, Shanghai 200032 (China); Zhang Zhengyu [Department of Radiation Oncology, Zhongshan Hospital, Fudan University, Shanghai 200032 (China); Zeng Haiying [Department of Pathology, Zhongshan Hospital, Fudan University, Shanghai 200032 (China); Liu Zhongshan [Department of Radiation Oncology, Zhongshan Hospital, Fudan University, Shanghai 200032 (China)

    2010-12-01

    Purpose: We determined whether anti-transforming growth factor-{beta} (TGF-{beta}) intervention could halt the progression of established radiation-induced liver fibrosis (RILF). Methods and Materials: A replication-defective adenoviral vector expressing the extracellular portion of human T{beta}RII and the Fc portion of immunoglobulin G fusion protein (AdT{beta}RIIFc) was produced. The entire rat liver was exposed to 30 Gy irradiation to generate a RILF model (RILFM). Then, RILFM animals were treated with AdT{beta}RIIFc (1 x 10{sup 11} plaque-forming units [PFU] of T{beta}RII), control virus (1 x 10{sup 11} PFU of AdGFP), or saline. Delayed radiation liver injury was assessed by histology and immunohistochemistry. Chronic oxidative stress damage, hepatic stellate cell activation, and hepatocyte regeneration were also analyzed. Results: In rats infected with AdT{beta}RIIFc, fibrosis was significantly improved compared with rats treated with AdGFP or saline, as assessed by histology, hydroxyproline content, and serum level of hyaluronic acid. Compared with AdGFP rats, AdT{beta}RIIFc-treated rats exhibited decreased oxidative stress damage and hepatic stellate cell activation and preserved liver function. Conclusions: Our results demonstrate that TGF-{beta} plays a critical role in the progression of liver fibrosis and suggest that anti-TGF-{beta} intervention is feasible and ameliorates established liver fibrosis. In addition, chronic oxidative stress may be involved in the progression of RILF.

  3. Calculation of laser induced impulse based on the laser supported detonation wave model with dissociation, ionization and radiation

    SciTech Connect (OSTI)

    Gan, Li, E-mail: ligan0001@gmail.com; Mousen, Cheng; Xiaokang, Li [College of Aerospace Science and Engineering, National University of Defense Technology, Changsha (China)] [College of Aerospace Science and Engineering, National University of Defense Technology, Changsha (China)

    2014-03-15

    In the laser intensity range that the laser supported detonation (LSD) wave can be maintained, dissociation, ionization and radiation take a substantial part of the incidence laser energy. There is little treatment on the phenomenon in the existing models, which brings obvious discrepancies between their predictions and the experiment results. Taking into account the impact of dissociation, ionization and radiation in the conservations of mass, momentum and energy, a modified LSD wave model is developed which fits the experimental data more effectively rather than the existing models. Taking into consideration the pressure decay of the normal and the radial rarefaction, the laser induced impulse that is delivered to the target surface is calculated in the air; and the dependencies of impulse performance on laser intensity, pulse width, ambient pressure and spot size are indicated. The results confirm that the dissociation is the pivotal factor of the appearance of the momentum coupling coefficient extremum. This study focuses on a more thorough understanding of LSD and the interaction between laser and matter.

  4. Activation of a c-K-ras oncogene by somatic mutation in mouse lymphomas induced by gamma radiation

    SciTech Connect (OSTI)

    Guerrero, I.; Villasante, A.; Corces, V.; Pellicer, A.

    1984-09-14

    Mouse tumors induced by gamma radiation are a useful model system for oncogenesis. DNA from such tumors contains an activated K-ras oncogene that can transform NIH 3T3 cells. This report describes the cloning of a fragment of the mouse K-ras oncogene containing the first exon from both a transformant in rat-2 cells and the brain of the same mouse that developed the tumor. Hybrid constructs containing one of the two pieces were made and only the plasmid including the first exon from the transformant gave rise to foci in NIH 3T3 cells. There was only a single base difference (G----A) in the exonic sequence, which changed glycine to aspartic acid in the transformant. By use of a synthetic oligonucleotide the presence of the mutation was demonstrated in the original tumor, ruling out modifications during DNA-mediated gene transfer and indicating that the alteration was present in the thymic lymphoma but absent from other nonmalignant tissue. The results are compatible with gamma radiation being a source of point mutations.

  5. ON AN ADAPTIVE CONTROL ALGORITHM FOR ADAPTIVE OPTICS APPLICATIONS

    E-Print Network [OSTI]

    ON AN ADAPTIVE CONTROL ALGORITHM FOR ADAPTIVE OPTICS APPLICATIONS MOODY T. CHU Abstract. The wavefront aberrations induced by atmospheric turbulence can severely degrade the performance of an optical imaging system. Adaptive optics refers to the process of removing unwanted wave front distortions

  6. ON AN ADAPTIVE CONTROL ALGORITHM FOR ADAPTIVE OPTICS APPLICATIONS

    E-Print Network [OSTI]

    ON AN ADAPTIVE CONTROL ALGORITHM FOR ADAPTIVE OPTICS APPLICATIONS MOODY T. CHU \\Lambda Abstract. The wavefront aberrations induced by atmospheric turbulence can severely degrade the performance of an optical imaging system. Adaptive optics refers to the process of removing unwanted wave front distortions

  7. Changes induced in a ZnS:Cr-based electroluminescent waveguide structure by intrinsic near-infrared laser radiation

    SciTech Connect (OSTI)

    Vlasenko, N. A. Oleksenko, P. F.; Mukhlyo, M. A.; Veligura, L. I.

    2013-08-15

    The causes of changes that occur in a thin-film electroluminescent metal-insulator-semiconductor-insulator-metal waveguide structure based on ZnS:Cr (Cr concentration of {approx}4 Multiplication-Sign 10{sup 20} cm{sup -3}) upon lasing ({lambda} Almost-Equal-To 2.6 {mu}m) and that induce lasing cessation are studied. It is established that lasing ceases because of light-scattering inhomogeneities formed in the structure and, hence, optical losses enhance. The origin of the inhomogeneities and the causes of their formation are clarified by studying the surface topology and the crystal structure of constituent layers of the samples before and after lasing. The studies are performed by means of atomic force microscopy and X-ray radiography. It is shown that a substantial increase in the sizes of grains on the surface of the structure is the manifestation of changes induced in the ZnS:Cr film by recrystallization. Recrystallization is initiated by local heating by absorbed laser radiation in existing Cr clusters and quickened by a strong electric field (>1 MV cm{sup -1}). The changes observed in the ZnS:Cr film are as follows: the textured growth of ZnS crystallites, an increase in the content of Cr clusters, and the appearance of some CrS and a rather high ZnO content. Some ways for improving the stability of lasing in the ZnS:Cr-based waveguide structures are proposed.

  8. Radiation-induced tetramer-to-dimer transition of Escherichia coli lactose repressor

    SciTech Connect (OSTI)

    Goffinont, S. [Centre de Biophysique Moleculaire, CNRS, rue C. Sadron, 45071 Orleans (France)] [Centre de Biophysique Moleculaire, CNRS, rue C. Sadron, 45071 Orleans (France); Davidkova, M. [Department of Radiation Dosimetry, Nuclear Physics Institute AS CR, Na Truhlarce 39/64, 18086, Prague 8 (Czech Republic)] [Department of Radiation Dosimetry, Nuclear Physics Institute AS CR, Na Truhlarce 39/64, 18086, Prague 8 (Czech Republic); Spotheim-Maurizot, M., E-mail: spotheim@cnrs-orleans.fr [Centre de Biophysique Moleculaire, CNRS, rue C. Sadron, 45071 Orleans (France)

    2009-08-21

    The wild type lactose repressor of Escherichia coli is a tetrameric protein formed by two identical dimers. They are associated via a C-terminal 4-helix bundle (called tetramerization domain) whose stability is ensured by the interaction of leucine zipper motifs. Upon in vitro {gamma}-irradiation the repressor losses its ability to bind the operator DNA sequence due to damage of its DNA-binding domains. Using an engineered dimeric repressor for comparison, we show here that irradiation induces also the change of repressor oligomerisation state from tetramer to dimer. The splitting of the tetramer into dimers can result from the oxidation of the leucine residues of the tetramerization domain.

  9. Radiation Pressure Induced Instabilities in Laser Interferometric Detectors of Gravitational Waves

    E-Print Network [OSTI]

    A. Pai; S. V. Dhurandhar; P. Hello; J-Y. Vinet

    2000-11-28

    The large scale interferometric gravitational wave detectors consist of Fabry-Perot cavities operating at very high powers ranging from tens of kW to MW for next generations. The high powers may result in several nonlinear effects which would affect the performance of the detector. In this paper, we investigate the effects of radiation pressure, which tend to displace the mirrors from their resonant position resulting in the detuning of the cavity. We observe a remarkable effect, namely, that the freely hanging mirrors gain energy continuously and swing with increasing amplitude. It is found that the `time delay', that is, the time taken for the field to adjust to its instantaneous equilibrium value, when the mirrors are in motion, is responsible for this effect. This effect is likely to be important in the optimal operation of the full-scale interferometers such as VIRGO and LIGO.

  10. The influence of TRP53 in the dose response of radiation-induced apoptosis, DNA repair and genomic stability in murine haematopoietic cells

    SciTech Connect (OSTI)

    Lemon, Jennifer A.; Taylor, Kristina; Verdecchia, Kyle; Phan, Nghi; Boreham, Douglas R.

    2014-01-01

    Apoptotic and DNA damage endpoints are frequently used as surrogate markers of cancer risk, and have been well-studied in the Trp53+/- mouse model. We report the effect of differing Trp53 gene status on the dose response of ionizing radiation exposures (0.01-2 Gy), with the unique perspective of determining if effects of gene status remain at extended time points. Here we report no difference in the dose response for radiation-induced DNA double-strand breaks in bone marrow and genomic instability (MN-RET levels) in peripheral blood, between wild-type (Trp53+/+) and heterozygous (Trp53+/-) mice. The dose response for Trp53+/+ mice showed higher initial levels of radiation-induced lymphocyte apoptosis relative to Trp53+/- between 0 and 1 Gy. Although this trend was observed up to 12 hours post-irradiation, both genotypes ultimately reached the same level of apoptosis at 14 hours, suggesting the importance of late-onset p53-independent apoptotic responses in this mouse model. Expected radiation-induced G1 cell cycle delay was observed in Trp53+/+ but not Trp53+/-. Although p53 has an important role in cancer risk, we have shown its influence on radiation dose response can be temporally variable. This research highlights the importance of caution when using haematopoietic endpoints as surrogates to extrapolate radiation-induced cancer risk estimation.

  11. DNA repair efficiency in germ cells and early mouse embryos and consequences for radiation-induced transgenerational genomic damage

    E-Print Network [OSTI]

    Marchetti, Francesco

    2009-01-01

    Development and the DOE Low Dose Radiation Research Program.in vivo by low doses of gamma radiation. Rad Res 156, 324-7.

  12. Radiation-Induced Alterations in Mouse Brain Development Characterized by Magnetic Resonance Imaging

    SciTech Connect (OSTI)

    Gazdzinski, Lisa M.; Cormier, Kyle; Lu, Fred G.; Lerch, Jason P.; Department of Medical Biophysics, University of Toronto, Toronto ; Wong, C. Shun; Department of Medical Biophysics, University of Toronto, Toronto; Department of Radiation Oncology, University of Toronto, Toronto ; Nieman, Brian J.

    2012-12-01

    Purpose: The purpose of this study was to identify regions of altered development in the mouse brain after cranial irradiation using longitudinal magnetic resonance imaging (MRI). Methods and Materials: Female C57Bl/6 mice received a whole-brain radiation dose of 7 Gy at an infant-equivalent age of 2.5 weeks. MRI was performed before irradiation and at 3 time points following irradiation. Deformation-based morphometry was used to quantify volume and growth rate changes following irradiation. Results: Widespread developmental deficits were observed in both white and gray matter regions following irradiation. Most of the affected brain regions suffered an initial volume deficit followed by growth at a normal rate, remaining smaller in irradiated brains compared with controls at all time points examined. The one exception was the olfactory bulb, which in addition to an early volume deficit, grew at a slower rate thereafter, resulting in a progressive volume deficit relative to controls. Immunohistochemical assessment revealed demyelination in white matter and loss of neural progenitor cells in the subgranular zone of the dentate gyrus and subventricular zone. Conclusions: MRI can detect regional differences in neuroanatomy and brain growth after whole-brain irradiation in the developing mouse. Developmental deficits in neuroanatomy persist, or even progress, and may serve as useful markers of late effects in mouse models. The high-throughput evaluation of brain development enabled by these methods may allow testing of strategies to mitigate late effects after pediatric cranial irradiation.

  13. A Novel Method for Predicting Late Genitourinary Toxicity After Prostate Radiation Therapy and the Need for Age-Based Risk-Adapted Dose Constraints

    SciTech Connect (OSTI)

    Ahmed, Awad A.; Egleston, Brian; Alcantara, Pino; Li, Linna; Pollack, Alan; Horwitz, Eric M.; Buyyounouski, Mark K.

    2013-07-15

    Background: There are no well-established normal tissue sparing dosevolume histogram (DVH) criteria that limit the risk of urinary toxicity from prostate radiation therapy (RT). The aim of this study was to determine which criteria predict late toxicity among various DVH parameters when contouring the entire solid bladder and its contents versus the bladder wall. The area under the histogram curve (AUHC) was also analyzed. Methods and Materials: From 1993 to 2000, 503 men with prostate cancer received 3-dimensional conformal RT (median follow-up time, 71 months). The whole bladder and the bladder wall were contoured in all patients. The primary endpoint was grade ?2 genitourinary (GU) toxicity occurring ?3 months after completion of RT. Cox regressions of time to grade ?2 toxicity were estimated separately for the entire bladder and bladder wall. Concordance probability estimates (CPE) assessed model discriminative ability. Before training the models, an external random test group of 100 men was set aside for testing. Separate analyses were performed based on the mean age (? 68 vs >68 years). Results: Age, pretreatment urinary symptoms, mean dose (entire bladder and bladder wall), and AUHC (entire bladder and bladder wall) were significant (P<.05) in multivariable analysis. Overall, bladder wall CPE values were higher than solid bladder values. The AUHC for bladder wall provided the greatest discrimination for late bladder toxicity when compared with alternative DVH points, with CPE values of 0.68 for age ?68 years and 0.81 for age >68 years. Conclusion: The AUHC method based on bladder wall volumes was superior for predicting late GU toxicity. Age >68 years was associated with late grade ?2 GU toxicity, which suggests that risk-adapted dose constraints based on age should be explored.

  14. Radiation-induced defects in GaN bulk grown by halide vapor phase epitaxy

    SciTech Connect (OSTI)

    Duc, Tran Thien; Pozina, Galia; Son, Nguyen Tien; Janzn, Erik; Hemmingsson, Carl; Ohshima, Takeshi

    2014-09-08

    Defects induced by electron irradiation in thick free-standing GaN layers grown by halide vapor phase epitaxy were studied by deep level transient spectroscopy. In as-grown materials, six electron traps, labeled D2 (E{sub C}0.24?eV), D3 (E{sub C}0.60?eV), D4 (E{sub C}0.69?eV), D5 (E{sub C}0.96?eV), D7 (E{sub C}1.19?eV), and D8, were observed. After 2?MeV electron irradiation at a fluence of 1??10{sup 14?}cm{sup ?2}, three deep electron traps, labeled D1 (E{sub C}0.12?eV), D5I (E{sub C}0.89?eV), and D6 (E{sub C}1.14?eV), were detected. The trap D1 has previously been reported and considered as being related to the nitrogen vacancy. From the annealing behavior and a high introduction rate, the D5I and D6 centers are suggested to be related to primary intrinsic defects.

  15. Radiation-induced defects in dense phases of crystalline and amorphous SiO sub 2

    SciTech Connect (OSTI)

    Devine, R.A.B. ); Hubner, K.

    1989-10-01

    We have studied electron-spin resonance in unirradiated and irradiated samples of naturally occurring stishovite. An unidentified central resonance ({ital g}{similar to}2.0030) with weak hyperfine lines is observed with a density 6{times}10{sup 14} per gram in unirradiated samples. Irradiation induces two sets of hyperfine lines, one sharp (1 gauss peak to peak) and one broad (14 gauss peak to peak) with hyperfine parameters {ital A}{sub {parallel}}=590 gauss, {ital A}{sub {perpendicular}}=457 gauss (sharp) and {ital A}{sub {parallel}}=525{sub {minus}15}{sup +0} gauss, {ital A}{sub {perpendicular}}=503{sub {minus}0}{sup +75} gauss, (broad). The latter set is consistent with {ital E}{sub 1}{sup {prime}} centers in densified, amorphous SiO{sub 2} with {rho}{ge}3.2 gm cm{sup {minus}3} whilst we identify the former with {ital E}{sub 1}{sup {prime}} defects in crystalline Stishovite. The hyperfine parameters for the crystalline phase cannot be interpreted simply in terms of the usual {ital s}-{ital p} electron model.

  16. Atmospheric Radiation Measurement (ARM) Data from Black Forest Germany for the Convective and Orographically Induced Precipitation Study (COPS)

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

    The primary goal of the ARM Program is to improve the treatment of cloud and radiation physics in global climate models in order to improve the climate simulation capabilities of these models. ARM maintains four major, permanent sites for data collection and deploys the ARM Mobile Facility (AMF) to other sites as determined. In 2007 the AMF operated in the Black Forest region of Germany as part of the Convective and Orographically Induced Precipitation Study (COPS). Scientists studied rainfall resulting from atmospheric uplift (convection) in mountainous terrain, otherwise known as orographic precipitation. This was part of a six -year duration of the German Quantitative Precipitation Forecasting (QPF) Program. COPS was endorsed as a Research and Development Project by the World Weather Research Program. This program was established by the World Meteorological Organization to develop improved and cost-effective forecasting techniques, with an emphasis on high-impact weather. A large collection of data plots based on data streams from specific instruments used at Black Forest are available via a link from ARM's Black Forest site information page. Users will be requested to create a password, but the plots and the data files in the ARM Archive are free for viewing and downloading.

  17. Radiation and bias switch-induced charge dynamics in Al{sub 2}O{sub 3}-based metal-oxide-semiconductor structures

    SciTech Connect (OSTI)

    Sambuco Salomone, L. Kasulin, A.; Carbonetto, S. H.; Garcia-Inza, M. A.; Redin, E. G.; Berbeglia, F.; Lipovetzky, J.; Faign, A.; Campabadal, F.

    2014-11-07

    Charge trapping dynamics induced by exposition to ?-ray ({sup 60}Co) radiation and bias switching in MOS capacitors with atomic layer deposited Al{sub 2}O{sub 3} as insulating layer was studied. Electrical characterization prior to irradiation showed voltage instabilities due to electron tunneling between the substrate and preexisting defects inside the dielectric layer. Real-time capacitance-voltage (C-V) measurements during irradiation showed two distinct regimes: For short times, the response is strongly bias dependent and linear with log(t), consistent with electron trapping/detrapping; for long times, the voltage shift is dominated by the radiation-induced hole capture being always negative and linear with dose. A simple model that takes into account these two phenomena can successfully reproduce the observed results.

  18. Gene induction and adaptive responses in irradiated cells: Mechanisms and clinical implications

    SciTech Connect (OSTI)

    Lehnert, S. [McGill Univ., Quebec (Canada)

    1995-01-01

    A characteristic of living things, conserved throughout evolution, is their capacity to react to environmental insult. From bacteria to yeast to human cells, environmental inputs induce changes in the program of genes expressed. A subset of this response, of particular interest to the radiobiologists and radiation oncologists who gathered for this meeting, is the case of radiation-mediated gene induction. A large number of genes have been reported to be up/down-regulated by ionizing radiation; some of these have been identified, while others have so far preserved their anonymity as bands and blots on gels and membranes. It is safe to say that many more such genes will be discovered in the future as the scientific and clinical significance of these processes is better understood. Substantial evidence, extending back many years, suggests the existence of an adaptive response, apparent as cellular radioprotective mechanisms which can be up-regulated after a small dose of radiation. At the molecular level, the timing of the changes in expression of induced genes and of the changes in levels of nuclear and cytoplasmic proteins which they encode is such as to support involvement of these elements in induced radioresistance. The adaptive response is one component of the battery of intrinsic factors which influence the response of tumors to radiation. Radiation-induced gene products encompass a spectrum of activities including cell cycle control, DNA repair, signal transduction, apoptosis and oncogenesis, all of which can influence tumor radioresponse and contribute to the multifactorial radioresistant phenotype. Growth factors and cytokines are encoded by several early and late-responding genes whose expression is up-regulated by radiation. These must be assumed to affect the toxicity of radiation toward early- and late-responding normal tissues profoundly by promoting repair or conversely by acting synergistically to enhance radiation damage.

  19. DNA repair efficiency in germ cells and early mouse embryos and consequences for radiation-induced transgenerational genomic damage

    SciTech Connect (OSTI)

    Marchetti, Francesco; Wyrobek, Andrew J.

    2009-01-18

    Exposure to ionizing radiation and other environmental agents can affect the genomic integrity of germ cells and induce adverse health effects in the progeny. Efficient DNA repair during gametogenesis and the early embryonic cycles after fertilization is critical for preventing transmission of DNA damage to the progeny and relies on maternal factors stored in the egg before fertilization. The ability of the maternal repair machinery to repair DNA damage in both parental genomes in the fertilizing egg is especially crucial for the fertilizing male genome that has not experienced a DNA repair-competent cellular environment for several weeks prior to fertilization. During the DNA repair-deficient period of spermatogenesis, DNA lesions may accumulate in sperm and be carried into the egg where, if not properly repaired, could result in the formation of heritable chromosomal aberrations or mutations and associated birth defects. Studies with female mice deficient in specific DNA repair genes have shown that: (i) cell cycle checkpoints are activated in the fertilized egg by DNA damage carried by the sperm; and (ii) the maternal genotype plays a major role in determining the efficiency of repairing genomic lesions in the fertilizing sperm and directly affect the risk for abnormal reproductive outcomes. There is also growing evidence that implicates DNA damage carried by the fertilizing gamete as a mediator of postfertilization processes that contribute to genomic instability in subsequent generations. Transgenerational genomic instability most likely involves epigenetic mechanisms or error-prone DNA repair processes in the early embryo. Maternal and embryonic DNA repair processes during the early phases of mammalian embryonic development can have far reaching consequences for the genomic integrity and health of subsequent generations.

  20. Effects of Adenovirus-Mediated Delivery of the Human Hepatocyte Growth Factor Gene in Experimental Radiation-Induced Heart Disease

    SciTech Connect (OSTI)

    Hu Shunying; Chen Yundai; Li Libing; Chen Jinlong; Wu Bin; Zhou, Xiao; Zhi Guang; Li Qingfang; Wang Rongliang; Duan Haifeng; Guo Zikuan; Yang Yuefeng; Xiao Fengjun; Wang Hua; Wang Lisheng

    2009-12-01

    Purpose: Irradiation to the heart may lead to late cardiovascular complications. The purpose of this study was to investigate whether adenovirus-mediated delivery of the human hepatocyte growth factor gene could reduce post-irradiation damage of the rat heart and improve heart function. Methods and Materials: Twenty rats received single-dose irradiation of 20 Gy gamma ray locally to the heart and were randomized into two groups. Two weeks after irradiation, these two groups of rats received Ad-HGF or mock adenovirus vector intramyocardial injection, respectively. Another 10 rats served as sham-irradiated controls. At post-irradiation Day 120, myocardial perfusion was tested by myocardial contrast echocardiography with contrast agent injected intravenously. At post-irradiation Day 180, cardiac function was assessed using the Langendorff technique with an isolated working heart model, after which heart samples were collected for histological evaluation. Results: Myocardial blood flow was significantly improved in HGF-treated animals as measured by myocardial contrast echocardiography at post-irradiation Day 120 . At post-irradiation Day 180, cardiac function was significantly improved in the HGF group compared with mock vector group, as measured by left ventricular peak systolic pressure (58.80 +- 9.01 vs. 41.94 +- 6.65 mm Hg, p < 0.05), the maximum dP/dt (5634 +- 1303 vs. 1667 +- 304 mm Hg/s, p < 0.01), and the minimum dP/dt (3477 +- 1084 vs. 1566 +- 499 mm Hg/s, p < 0.05). Picrosirius red staining analysis also revealed a significant reduction of fibrosis in the HGF group. Conclusion: Based on the study findings, hepatocyte growth factor gene transfer can attenuate radiation-induced cardiac injury and can preserve cardiac function.

  1. DNA repair efficiency in germ cells and early mouse embryos and consequences for radiation-induced transgenerational genomic damage

    E-Print Network [OSTI]

    Marchetti, Francesco

    2009-01-01

    Kastan, M. B. (1997). DNA damage induces phosphorylation ofby ATM in response to DNA damage. Science 281, Barber, R. ,Nussenzweig, A. (2002). DNA damage-induced G2-M checkpoint

  2. A model of interactions between radiation-induced oxidative stress, protein and DNA damage in Deinococcus radiodurans

    E-Print Network [OSTI]

    Brenner, David Jonathan

    . For example, oxidative stress triggered by even quite low doses of radiation can produce an alteration repair may function more efficiently. These processes probably occur to some extent even at low doses of radiation/oxidative stress, but they are easiest to investigate at high doses, where both DNA and protein

  3. Repair of radiation-induced heat-labile sites is independent of DNA-PKcs, XRCC1 or PARP

    SciTech Connect (OSTI)

    Stenerlw, Bo; Karlsson, Karin H.; Radulescu, Irina; Rydberg, Bjorn; Stenerlow, Bo

    2008-04-29

    Ionizing radiation induces a variety of different DNA lesions: in addition to the most critical DNA damage, the DSB, numerous base alterations, SSBs and other modifications of the DNA double-helix are formed. When several non-DSB lesions are clustered within a short distance along DNA, or close to a DSB, they may interfere with the repair of DSBs and affect the measurement of DSB induction and repair. We have previously shown that a substantial fraction of DSBs measured by pulsed-field gel electrophoresis (PFGE) are in fact due to heat-labile sites (HLS) within clustered lesions, thus reflecting an artifact of preparation of genomic DNA at elevated temperature. To further characterize the influence of HLS on DSB induction and repair, four human cell lines (GM5758, GM7166, M059K, U-1810) with apparently normal DSB rejoining were tested for bi-phasic rejoining after gamma irradiation. When heat-released DSBs were excluded from the measurements the fraction of fast rejoining decreased to less than 50% of the total. However, neither the half-times of the fast (t{sub 1/2} = 7-8 min) or slow (t{sub 1/2} = 2.5 h) DSB rejoining were changed significantly. At t=0 the heat-released DSBs accounted for almost 40% of the DSBs, corresponding to 10 extra DSB/cell/Gy in the initial DSB yield. These heat-released DSBs were repaired within 60-90 min in all tested cells, including M059K cells treated with wortmannin or DNA-PKcs defect M059J cells. Furthermore, cells lacking XRCC1 or Poly(ADP-ribose) polymerase-1 (PARP-1) rejoined both total DSBs and heat-released DSBs similar to normal cells. In summary, the presence of heat-labile sites have a substantial impact on DSB induction yields and DSB rejoining rates measured by pulsed-field gel electrophoresis, and HLS repair is independent of DNA-PKcs, XRCC1 and PARP.

  4. Solid-state polymerization of acrylamide and its derivatives complexed with some Lewis acids. II. Radiation-induced in-source polymerization

    SciTech Connect (OSTI)

    Zurakowska-Orszagh, J.; Mirowski, K.; Chajewski, A.

    1982-07-01

    Radiation-induced solid-state polymerizations of complexes of N-tert-butylacrylamide, N-tert-amylacrylamide, and N-tert-hexylacrylamide with zinc chloride and zinc bromide have been studied. An accelerating effect of temperature and an inhibiting effect of oxygen on the polymerization process were observed. The activation energies have been established. The influence of monomer structure as well as the halide used on the polymerization rate have been discussed and some regularities have been pointed out. The polymers obtained show good solubilities in common solvents, which proves that they are not crosslinked.

  5. Discovery and Characterization of Radiation Mitigator Yel002

    E-Print Network [OSTI]

    Rivina, Yelena Olegovna

    2013-01-01

    20. Bonner WM. Low-dose radiation: thresholds, bystanderR. ; Haran-Ghera, N. Low doses of radiation induce systemicattributable to low doses of ionizing radiation: assessing

  6. Silver Clear Nylon Dressing is Effective in Preventing Radiation-Induced Dermatitis in Patients With Lower Gastrointestinal Cancer: Results From a Phase III Study

    SciTech Connect (OSTI)

    Niazi, Tamim M. [Segal Cancer Centre, Department of Radiation Oncology, Jewish General Hospital, McGill University (Canada)] [Segal Cancer Centre, Department of Radiation Oncology, Jewish General Hospital, McGill University (Canada); Vuong, Te, E-mail: tvuong@jgh.mcgill.ca [Segal Cancer Centre, Department of Radiation Oncology, Jewish General Hospital, McGill University (Canada)] [Segal Cancer Centre, Department of Radiation Oncology, Jewish General Hospital, McGill University (Canada); Azoulay, Laurant [Department of Epidemiology, Jewish General Hospital, McGill University (Canada)] [Department of Epidemiology, Jewish General Hospital, McGill University (Canada); Marijnen, Corrie [Department of Clinical Oncology, Leiden University Medical Center, Amsterdam (Netherlands)] [Department of Clinical Oncology, Leiden University Medical Center, Amsterdam (Netherlands); Bujko, Kryzstof [Department of Radiotherapy, The Maria Sklodowska-Curie Memorial Cancer Centre, Warsaw (Poland)] [Department of Radiotherapy, The Maria Sklodowska-Curie Memorial Cancer Centre, Warsaw (Poland); Nasr, Elie [Department of Radiation Oncology, Hotel-Dieu de France Hospital (Lebanon)] [Department of Radiation Oncology, Hotel-Dieu de France Hospital (Lebanon); Lambert, Christine; Duclos, Marie; Faria, Sergio; David, Marc [Department of Radiation Oncology, Montreal-General-Hospital, McGill University, Montreal (Canada)] [Department of Radiation Oncology, Montreal-General-Hospital, McGill University, Montreal (Canada); Cummings, Bernard [Department of Radiation Oncology, Princess Margaret Hospital, University of Toronto (Canada)] [Department of Radiation Oncology, Princess Margaret Hospital, University of Toronto (Canada)

    2012-11-01

    Purpose: For patients with anal canal and advanced rectal cancer, chemoradiation therapy is a curative modality or an important adjunct to surgery. Nearly all patients treated with chemoradiation experience some degree of radiation-induced dermatitis (RID). Prevention and effective treatment of RID, therefore, is of considerable clinical relevance. The present phase III randomized trial compared the efficacy of silver clear nylon dressing (SCND) with that of standard skin care for these patients. Methods and Materials: A total of 42 rectal or anal canal cancer patients were randomized to either a SCND or standard skin care group. SCND was applied from Day 1 of radiation therapy (RT) until 2 weeks after treatment completion. In the control arm, sulfadiazine cream was applied at the time of skin dermatitis. Printed digital photographs taken 2 weeks prior to, on the last day, and two weeks after the treatment completion were scored by 10 blinded readers, who used the common toxicity scoring system for skin dermatitis. Results: The radiation dose ranged from 50.4 to 59.4 Gy, and there were no differences between the 2 groups. On the last day of RT, when the most severe RID occurs, the mean dermatitis score was 2.53 (standard deviation [SD], 1.17) for the standard and 1.67 (SD, 1.2; P=.01) for the SCND arm. At 2 weeks after RT, the difference was 0.39 points in favor of SCND (P=.39). There was considerable intraclass correlation among the 10 observers. Conclusions: Silver clear nylon dressing is effective in reducing RID in patients with lower gastrointestinal cancer treated with combined chemotherapy and radiation treatment.

  7. Swift heavy ion irradiation of ZnO nanoparticles embedded in silica: Radiation-induced deoxidation and shape elongation

    SciTech Connect (OSTI)

    Amekura, H.; Tsuya, D.; Mitsuishi, K.; Nakayama, Y. [National Institute for Materials Science (NIMS), Tsukuba, Ibaraki 305-0003 (Japan)] [National Institute for Materials Science (NIMS), Tsukuba, Ibaraki 305-0003 (Japan); Okubo, N.; Ishikawa, N. [Japan Atomic Energy Agency (JAEA), Tokai, Ibaraki (Japan)] [Japan Atomic Energy Agency (JAEA), Tokai, Ibaraki (Japan); Singh, U. B.; Khan, S. A.; Avasthi, D. K. [Inter-University Accelerator Centre (IUAC), New Delhi (India)] [Inter-University Accelerator Centre (IUAC), New Delhi (India); Mohapatra, S. [Guru Gobind Singh Indraprastha University, New Delhi (India)] [Guru Gobind Singh Indraprastha University, New Delhi (India)

    2013-11-11

    ZnO nanoparticles (NPs) embedded in amorphous SiO{sub 2} were irradiated with 200 MeV Xe{sup 14+} swift heavy ions (SHIs) to a fluence of 5.0 10{sup 13} ions/cm{sup 2}. Optical linear dichroism was induced in the samples by the irradiation, indicating shape transformation of the NPs from spheres to anisotropic ones. Transmission electron microscopy observations revealed that some NPs were elongated to prolate shapes; the elongated NPs consisted not of ZnO but of Zn metal. The SHI irradiation induced deoxidation of small ZnO NPs and successive shape elongation of the deoxidized metal NPs.

  8. On the possibility of cosmic ray-induced ionizing radiation-powered life in subsurface environments in the Universe

    E-Print Network [OSTI]

    Atri, Dimitra

    2015-01-01

    Photosynthesis is a highly efficient mechanism developed by terrestrial life to utilize the energy from photons of solar origin for biological use. Subsurface regions are isolated from the photosphere, and consequently are incapable of utilizing this energy. This opens up the opportunity for life to cultivate alternative mechanisms in order to take advantage of other available energy sources. Studies have shown that in subsurface environments, life can use energy generated from geochemical and geothermal processes to sustain a minimal metabolism. Another mechanism is radiolysis, in which particles emitted by radioactive substances are indirectly utilized for metabolism. One such example is the bacterium fueled by radiation, found 2 miles deep in a South African mine, which consumes hydrogen formed from particles emitted by radioactive U, Th and K present in rock. An additional source of radiation in the subsurface environments is secondary particles, such as muons generated by Galactic Cosmic Rays (GCRs). It ...

  9. Adaptive Sensitivity 1 Adaptive Sensitivity

    E-Print Network [OSTI]

    Ginosar, Ran

    1 Adaptive Sensitivity 1 Adaptive Sensitivity Ran Ginosar Introduction Solid state (and other) sensors have a limited dynamic range Din: where both thresholds are measured in terms of the light intensity (Dout is specified as the ratio of the output signals). Light Intensity Output Signal Saturation

  10. SNP in TXNRD2 Associated With Radiation-Induced Fibrosis: A Study of Genetic Variation in Reactive Oxygen Species Metabolism and Signaling

    SciTech Connect (OSTI)

    Edvardsen, Hege; K. G. Jebsen Breast cancer centre, Institute for Clinical Medicine, University of Oslo, Oslo ; Landmark-Hyvik, Hege; K. G. Jebsen Breast cancer centre, Institute for Clinical Medicine, University of Oslo, Oslo ; Reinertsen, Kristin V.; Zhao, Xi; K. G. Jebsen Breast cancer centre, Institute for Clinical Medicine, University of Oslo, Oslo ; Grenaker-Alns, Grethe Irene; Nebdal, Daniel; Syvnen, Ann-Christine; Rdningen, Olaug; Alsner, Jan; Overgaard, Jens; Borresen-Dale, Anne-Lise; K. G. Jebsen Breast cancer centre, Institute for Clinical Medicine, University of Oslo, Oslo ; Foss, Sophie D.; National Resource Centre for Late Effects after Cancer Treatment, OUS Radiumhospitalet, Oslo ; Kristensen, Vessela N.; K. G. Jebsen Breast cancer centre, Institute for Clinical Medicine, University of Oslo, Oslo; Department of Clinical Molecular Biology , Division of Medicine, Ahus University Hospital

    2013-07-15

    Purpose: The aim of the study was to identify noninvasive markers of treatment-induced side effects. Reactive oxygen species (ROS) are generated after irradiation, and genetic variation in genes related to ROS metabolism might influence the level of radiation-induced adverse effects (AEs). Methods and Materials: 92 breast cancer (BC) survivors previously treated with hypofractionated radiation therapy were assessed for the AEs subcutaneous atrophy and fibrosis, costal fractures, lung fibrosis, pleural thickening, and telangiectasias (median follow-up time 17.1 years). Single-nucleotide polymorphisms (SNPs) in 203 genes were analyzed for association to AE grade. SNPs associated with subcutaneous fibrosis were validated in an independent BC survivor material (n=283). The influence of the studied genetic variation on messenger ribonucleic acid (mRNA) expression level of 18 genes previously associated with fibrosis was assessed in fibroblast cell lines from BC patients. Results: Subcutaneous fibrosis and atrophy had the highest correlation (r=0.76) of all assessed AEs. The nonsynonymous SNP rs1139793 in TXNRD2 was associated with grade of subcutaneous fibrosis, the reference T-allele being more prevalent in the group experiencing severe levels of fibrosis. This was confirmed in another sample cohort of 283 BC survivors, and rs1139793 was found significantly associated with mRNA expression level of TXNRD2 in blood. Genetic variation in 24 ROS-related genes, including EGFR, CENPE, APEX1, and GSTP1, was associated with mRNA expression of 14 genes previously linked to fibrosis (P?.005). Conclusion: Development of subcutaneous fibrosis can be associated with genetic variation in the mitochondrial enzyme TXNRD2, critically involved in removal of ROS, and maintenance of the intracellular redox balance.

  11. Terahertz radiation-induced sub-cycle field electron emission across a split-gap dipole antenna

    E-Print Network [OSTI]

    Zhang, Jingdi; Fan, Kebin; Wang, Xiaoning; Zhang, Gu-Feng; Geng, Kun; Zhang, Xin; Averitt, Richard D

    2015-01-01

    We use intense terahertz pulses to excite the resonant mode (0.6 THz) of a micro-fabricated dipole antenna with a vacuum gap. The dipole antenna structure enhances the peak amplitude of the in-gap THz electric field by a factor of ~170. Above an in-gap E-field threshold amplitude of ~10 MVcm-1, THz-induced field electron emission is observed (TIFEE) as indicated by the field-induced electric current across the dipole antenna gap. Field emission occurs within a fraction of the driving THz period. Our analysis of the current (I) and incident electric field (E) is in agreement with a Millikan-Lauritsen analysis where log (I) exhibits a linear dependence on 1/E. Numerical estimates indicate that the electrons are accelerated to a value of approximately one tenth of the speed of light.

  12. Dual-Energy Micro-Computed Tomography Imaging of Radiation-Induced Vascular Changes in Primary Mouse Sarcomas

    SciTech Connect (OSTI)

    Moding, Everett J. [Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, North Carolina (United States)] [Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, North Carolina (United States); Clark, Darin P.; Qi, Yi [Center for In Vivo Microscopy, Department of Radiology, Duke University Medical Center, Durham, North Carolina (United States)] [Center for In Vivo Microscopy, Department of Radiology, Duke University Medical Center, Durham, North Carolina (United States); Li, Yifan; Ma, Yan [Department of Radiation Oncology, Duke University Medical Center, Durham, North Carolina (United States)] [Department of Radiation Oncology, Duke University Medical Center, Durham, North Carolina (United States); Ghaghada, Ketan [The Edward B. Singleton Department of Pediatric Radiology, Texas Children's Hospital, Houston, Texas (United States)] [The Edward B. Singleton Department of Pediatric Radiology, Texas Children's Hospital, Houston, Texas (United States); Johnson, G. Allan [Center for In Vivo Microscopy, Department of Radiology, Duke University Medical Center, Durham, North Carolina (United States)] [Center for In Vivo Microscopy, Department of Radiology, Duke University Medical Center, Durham, North Carolina (United States); Kirsch, David G. [Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, North Carolina (United States) [Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, North Carolina (United States); Department of Radiation Oncology, Duke University Medical Center, Durham, North Carolina (United States); Badea, Cristian T., E-mail: cristian.badea@duke.edu [Center for In Vivo Microscopy, Department of Radiology, Duke University Medical Center, Durham, North Carolina (United States)

    2013-04-01

    Purpose: To evaluate the effects of radiation therapy on primary tumor vasculature using dual-energy (DE) micro-computed tomography (micro-CT). Methods and Materials: Primary sarcomas were generated with mutant Kras and p53. Unirradiated tumors were compared with tumors irradiated with 20 Gy. A liposomal-iodinated contrast agent was administered 1 day after treatment, and mice were imaged immediately after injection (day 1) and 3 days later (day 4) with DE micro-CT. CT-derived tumor sizes were used to assess tumor growth. After DE decomposition, iodine maps were used to assess tumor fractional blood volume (FBV) at day 1 and tumor vascular permeability at day 4. For comparison, tumor vascularity and vascular permeability were also evaluated histologically by use of CD31 immunofluorescence and fluorescently-labeled dextrans. Results: Radiation treatment significantly decreased tumor growth from day 1 to day 4 (P<.05). There was a positive correlation between CT measurement of tumor FBV on day 1 and extravasated iodine on day 4 with microvascular density (MVD) on day 4 (R{sup 2}=0.53) and dextran accumulation (R{sup 2}=0.63) on day 4, respectively. Despite no change in MVD measured by histology, tumor FBV significantly increased after irradiation as measured by DE micro-CT (0.070 vs 0.091, P<.05). Both dextran and liposomal-iodine accumulation in tumors increased significantly after irradiation, with dextran fractional area increasing 5.2-fold and liposomal-iodine concentration increasing 4.0-fold. Conclusions: DE micro-CT is an effective tool for noninvasive assessment of vascular changes in primary tumors. Tumor blood volume and vascular permeability increased after a single therapeutic dose of radiation treatment.

  13. A new time-dependent analytic model for radiation-induced photocurrent in finite 1D epitaxial diodes.

    SciTech Connect (OSTI)

    Verley, Jason C.; Axness, Carl L.; Hembree, Charles Edward; Keiter, Eric Richard; Kerr, Bert

    2012-04-01

    Photocurrent generated by ionizing radiation represents a threat to microelectronics in radiation environments. Circuit simulation tools such as SPICE [1] can be used to analyze these threats, and typically rely on compact models for individual electrical components such as transistors and diodes. Compact models consist of a handful of differential and/or algebraic equations, and are derived by making simplifying assumptions to any of the many semiconductor transport equations. Historically, many photocurrent compact models have suffered from accuracy issues due to the use of qualitative approximation, rather than mathematically correct solutions to the ambipolar diffusion equation. A practical consequence of this inaccuracy is that a given model calibration is trustworthy over only a narrow range of operating conditions. This report describes work to produce improved compact models for photocurrent. Specifically, an analytic model is developed for epitaxial diode structures that have a highly doped subcollector. The analytic model is compared with both numerical TCAD calculations, as well as the compact model described in reference [2]. The new analytic model compares well against TCAD over a wide range of operating conditions, and is shown to be superior to the compact model from reference [2].

  14. Precise method of compensating radiation-induced errors in a hot-cathode-ionization gauge with correcting electrode

    SciTech Connect (OSTI)

    Saeki, Hiroshi Magome, Tamotsu

    2014-10-06

    To compensate pressure-measurement errors caused by a synchrotron radiation environment, a precise method using a hot-cathode-ionization-gauge head with correcting electrode, was developed and tested in a simulation experiment with excess electrons in the SPring-8 storage ring. This precise method to improve the measurement accuracy, can correctly reduce the pressure-measurement errors caused by electrons originating from the external environment, and originating from the primary gauge filament influenced by spatial conditions of the installed vacuum-gauge head. As the result of the simulation experiment to confirm the performance reducing the errors caused by the external environment, the pressure-measurement error using this method was approximately less than several percent in the pressure range from 10{sup ?5} Pa to 10{sup ?8} Pa. After the experiment, to confirm the performance reducing the error caused by spatial conditions, an additional experiment was carried out using a sleeve and showed that the improved function was available.

  15. SU-E-J-65: Evaluation of a Radiation-Induced Cell Proliferation Probability Formula Using Monte Carlo Simulation

    SciTech Connect (OSTI)

    Watanabe, Y; Dahlman, E [University of Minnesota, Minneapolis, MN (United States)

    2014-06-01

    Purpose: To evaluate the analytic formula of the cell death probability after single fraction dose. Methods: Cancer cells endlessly divide, but radiation causes the cancer cells to die. Not all cells die right away after irradiation. Instead, they continue dividing for next few cell cycles before they stop dividing and die. At the end of every cell cycle, the cell decides if it undertakes the mitotic process with a certain probability, Pdiv, which is altered by the radiation. Previously, by using a simple analytic model of radiobiology experiments, we obtained a formula of Pdeath (= 1 ? Pdiv). A question is if the proposed probability can reproduce the well-known survival data of the LQ model. In this study, we evaluated the formula by doing a Monte Carlo simulation of the cell proliferation process. Starting with Ns seed cells, the cell proliferation process was simulated for N generations or until all cells die. We counted the number of living cells at the end. Assuming that the cell colony survived when more than Nc cells were still alive, the surviving fraction S was estimated. We compared the S vs. dose, or S-D curve, with the LQ model. Results: The results indicated that our formula does not reproduce the experimentally observed S-D curve without selecting appropriate ? and ?/?. With parameter optimization, there was a fair agreement between the MC result and the LQ curve of dose lower than 20Gy. However, the survival fraction of MC decreased much faster in comparison to the LQ data for doses higher than 20 Gy. Conclusion: This study showed that the previously derived probability of cell death per cell cycle is not sufficiently accurate to replicate common radiobiological experiments. The formula must be modified by considering its cell cycle dependence and some other unknown effects.

  16. Influence of adaptive mesh refinement and the hydro solver on shear-induced mass stripping in a minor-merger scenario

    E-Print Network [OSTI]

    Schmidt, W; Iapichino, L; Vazza, F; Almgren, A S

    2014-01-01

    We compare two different codes for simulations of cosmological structure formation to investigate the sensitivity of hydrodynamical instabilities to numerics, in particular, the hydro solver and the application of adaptive mesh refinement (AMR). As a simple test problem, we consider an initially spherical gas cloud in a wind, which is an idealized model for the merger of a subcluster or galaxy with a big cluster. Based on an entropy criterion, we calculate the mass stripping from the subcluster as a function of time. Moreover, the turbulent velocity field is analyzed with a multi-scale filtering technique. We find remarkable differences between the commonly used PPM solver with directional splitting in the Enzo code and an unsplit variant of PPM in the Nyx code, which demonstrates that different codes can converge to systematically different solutions even when using uniform grids. For the test case of an unbound cloud, AMR simulations reproduce uniform-grid results for the mass stripping quite well, although...

  17. Adaptive sampler

    DOE Patents [OSTI]

    Watson, B.L.; Aeby, I.

    1980-08-26

    An adaptive data compression device for compressing data is described. The device has a frequency content, including a plurality of digital filters for analyzing the content of the data over a plurality of frequency regions, a memory, and a control logic circuit for generating a variable rate memory clock corresponding to the analyzed frequency content of the data in the frequency region and for clocking the data into the memory in response to the variable rate memory clock.

  18. Radiation physics, biophysics, and radiation biology

    SciTech Connect (OSTI)

    Hall, E.J.; Zaider, M.

    1991-05-01

    Research at the Radiological Research Laboratory is a blend of physics, chemistry, and biology, involving research at the basic level with the admixture of a small proportion of pragmatic or applied research in support of radiation protection and/or radiotherapy. Current research topics include: oncogenic transformation assays, mutation studies involving interactions between radiation and environmental contaminants, isolation, characterization and sequencing of a human repair gene, characterization of a dominant transforming gene found in C3H 10T1/2 cells, characterize ab initio the interaction of DNA and radiation, refine estimates of the radiation quality factor Q, a new mechanistic model of oncogenesis showing the role of long-term low dose medium LET radiation, and time dependent modeling of radiation induced chromosome damage and subsequent repair or misrepair.

  19. Role of repair processes in neoplastic transformation induced by ionizing radiation in C3H/10T1/2 cells

    SciTech Connect (OSTI)

    Hill, C.K.; Elkind, M.M.; Han, A.

    1984-01-01

    The paper discusses the mechanisms underlying the induction and modulation of neoplastic transformation by the type and mode of radiation delivery. Those features of transformation in vitro characteristic of induction by ionizing radiation are described. 33 references, 10 figures. (ACR)

  20. CRYOPUMP MEASUREMENTS RELATING TO SAFETY, PUMPING SPEED, AND RADIATION OUTGASSING

    E-Print Network [OSTI]

    Graham, W.G.

    2011-01-01

    SPEED, AND RADIATION OUTGASSING* William G. Graham andspeeds, and to study outgassing such as might be produced byi w I C" Radiation Outgassing Rad:lation-induced outgassing

  1. Evolution of extreme resistance to ionizing radiation via genetic...

    Office of Scientific and Technical Information (OSTI)

    DOE PAGES Search Results Published Article: Evolution of extreme resistance to ionizing radiation via genetic adaptation of DNA repair Title: Evolution of extreme resistance to...

  2. adaptation of DNA repair Byrne, Rose T; Klingele, Audrey J; Cabot...

    Office of Scientific and Technical Information (OSTI)

    Evolution of extreme resistance to ionizing radiation via genetic adaptation of DNA repair Byrne, Rose T; Klingele, Audrey J; Cabot, Eric L; Schackwitz, Wendy S; Martin, Jeffrey A;...

  3. Final Report - Epigenetics of low dose radiation effects in an animal model

    SciTech Connect (OSTI)

    Kovalchuk, Olga

    2014-10-22

    This project sought mechanistic understanding of the epigenetic response of tissues as well as the consequences of those responses, when induced by low dose irradiation in a well-established model system (mouse). Based on solid and extensive preliminary data we investigated the molecular epigenetic mechanisms of in vivo radiation responses, particularly effects of low, occupationally relevant radiation exposures on the genome stability and adaptive response in mammalian tissues and organisms. We accumulated evidence that low dose irradiation altered epigenetic profiles and impacted radiation target organs of the exposed animals. The main long-term goal was to dissect the epigenetic basis of induction of the low dose radiation-induced genome instability and adaptive response and the specific fundamental roles of epigenetic changes (i.e. DNA methylation, histone modifications and miRNAs) in their generation. We hypothesized that changes in global and regional DNA methylation, global histone modifications and regulatory microRNAs played pivotal roles in the generation and maintenance low-dose radiation-induced genome instability and adaptive response. We predicted that epigenetic changes influenced the levels of genetic rearrangements (transposone reactivation). We hypothesized that epigenetic responses from low dose irradiation were dependent on exposure regimes, and would be greatest when organisms are exposed in a protracted/fractionated manner: fractionated exposures > acute exposures. We anticipated that the epigenetic responses were correlated with the gene expression levels. Our immediate objectives were: To investigate the exact nature of the global and locus-specific DNA methylation changes in the LDR exposed cells and tissues and dissect their roles in adaptive response To investigate the roles of histone modifications in the low dose radiation effects and adaptive response To dissect the roles of regulatory microRNAs and their targets in low dose radiation effects and adaptive response To correlate the levels of epigenetic changes with genetic rearrangement levels and gene expression patterns. In sum, we determined the precise global and locus-specific DNA methylation patterns in the LDR-exposed cells and tissues of mice, and to correlated DNA methylation changes with the gene expression patterns and manifestations of genome instability. We also determined the alterations of global histone modification pattern in the LDR exposed tissues. Additionally, we established the nature of microRNAome changes in the LDR exposed tissue. In this study we for the first time found that LDR exposure caused profound tissue-specific epigenetic changes in the exposed tissues. We established that LDR exposure affect methylation of repetitive elements in the murine genome, causes changes in histone methylation, acetylation and phosphorylation. Importantly, we found that LDR causes profound and persistent effects on small RNA profiles and gene expression, and that miRNAs are excellent biomarkers of LDR exposure. Furthermore, we extended our analysis and studied LDR effects in rat tissues and human tissues and cell lines. There we also analyzed LDR-induced gene expression, DNA methylation and miRNA changes. Our datasets laid foundation for several new research projects aimed to understand molecular underpinnings of low dose radiation responses, and biological repercussions of low dose radiation effects and radiation carcinogenesis.

  4. Radiation: Radiation Control (Indiana)

    Broader source: Energy.gov [DOE]

    It is the policy of the state to encourage the constructive uses of radiation and to control its harmful effects. This section contains regulations pertaining to the manufacture, use,...

  5. Radioadaptive Response Induced by Alpha-Particle-Induced Stress

    E-Print Network [OSTI]

    Yu, Peter K.N.

    of radioadaptive response (RAR) by com- munication of radiation-induced bystander signals. RAR is a kind of low-dose in the unirradiated embryos. Introduction Recent research have demonstrated the communication of radiation radiation effect, which occurs when a small preceding priming dose decreases the biological effectiveness

  6. Topics in radiation at accelerators: Radiation physics for personnel and environmental protection

    SciTech Connect (OSTI)

    Cossairt, J.D.

    1993-11-01

    This report discusses the following topics: Composition of Accelerator Radiation Fields; Shielding of Electrons and Photons at Accelerators; Shielding of Hadrons at Accelerators; Low Energy Prompt Radiation Phenomena; Induced Radioactivity at Accelerators; Topics in Radiation Protection Instrumentation at Accelerators; and Accelerator Radiation Protection Program Elements.

  7. Generalized Adaptive A* Xiaoxun Sun

    E-Print Network [OSTI]

    Yeoh, William

    Generalized Adaptive A* Xiaoxun Sun USC Computer Science Los Angeles, California xiaoxuns spaces changes. Adaptive A* [7] is a Cite as: Generalized Adaptive A*, Xiaoxun Sun, Sven Koenig

  8. Ultraviolet-light-induced transformation of human primary cells

    SciTech Connect (OSTI)

    Sutherland, B.M.

    1981-01-01

    The development of model systems for probing the ultraviolet radiation induced oncogenic transformation of human skin cells is described. (ACR)

  9. Augmentation of adaptation data

    E-Print Network [OSTI]

    Vipperla, Ravi Chander; Renals, Steve; Frankel, Joe

    2010-01-01

    Linear regression based speaker adaptation approaches can improve Automatic Speech Recognition (ASR) accuracy significantly for a target speaker. However, when the available adaptation data is limited to a few seconds, the ...

  10. Radiation physics, biophysics, and radiation biology

    SciTech Connect (OSTI)

    Hall, E.J.

    1992-05-01

    The following research programs from the Center for Radiological Research of Columbia University are described: Design and development of a new wall-less ultra miniature proportional counter for nanodosimetry; some recent measurements of ionization distributions for heavy ions at nanometer site sizes with a wall-less proportional counter; a calculation of exciton energies in periodic systems with helical symmetry: application to a hydrogen fluoride chain; electron energy-loss function in polynucleotide and the question of plasmon excitation; a non-parametric, microdosimetric-based approach to the evaluation of the biological effects of low doses of ionizing radiation; high-LET radiation risk assessment at medium doses; high-LET radiobiological effects: increased lesion severity or increased lesion proximity; photoneutrons generated by high energy medical linacs; the biological effectiveness of neutrons; implications for radiation protection; molecular characterization of oncogenes induced by neutrons; and the inverse dose-rate effect for oncogenic transformation by charged particles is LET dependent.

  11. Stress map for ion irradiation: Depth-resolved dynamic competition between radiation-induced viscoelastic phenomena in SiO2

    E-Print Network [OSTI]

    Polman, Albert

    doping technology in integrated circuit manufacturing and is used to locally modify and tailor optical of the highly anisotropic ion-induced thermal spike, causes anisotropic strain that freezes in as the thermal or electronic energy loss (stopping), which are both highly depth dependent. In this letter we evaluate

  12. Danger radiations

    ScienceCinema (OSTI)

    None

    2011-04-25

    Le confrencier Mons.Hofert parle des dangers et risques des radiations, le contrle des zones et les prcautions prendre ( p.ex. film badge), comment mesurer les radiations etc.

  13. Topics in radiation at accelerators: Radiation physics for personnel and environmental protection

    SciTech Connect (OSTI)

    Cossairt, J.D.

    1996-10-01

    In the first chapter, terminology, physical and radiological quantities, and units of measurement used to describe the properties of accelerator radiation fields are reviewed. The general considerations of primary radiation fields pertinent to accelerators are discussed. The primary radiation fields produced by electron beams are described qualitatively and quantitatively. In the same manner the primary radiation fields produced by proton and ion beams are described. Subsequent chapters describe: shielding of electrons and photons at accelerators; shielding of proton and ion accelerators; low energy prompt radiation phenomena; induced radioactivity at accelerators; topics in radiation protection instrumentation at accelerators; and accelerator radiation protection program elements.

  14. RESMDD'02 Radiation in Life Sciences: Hartmut F.-W. Sadrozinski , SCIPP Radiation Effects in

    E-Print Network [OSTI]

    California at Santa Cruz, University of

    for Cancer Research to induce DNA Faults #12;RESMDD'02 Radiation in Life Sciences: Hartmut F.-W. Sadrozinski Parameters to Describe Quality of Radiation Dose & Dose Rate Fluence & Fluence Rate Linear EnergyVery High Repairable ?1-5Low Damage# of Ionizations (Cluster Size) LET #12;RESMDD'02 Radiation in Life

  15. Development of a New Analysis Tool for Evaluating and Correcting for Weather Conditions that Constrain Radiation Portal Monitor Performance

    SciTech Connect (OSTI)

    Guzzardo, Tyler [ORNL] [ORNL; Livesay, Jake [ORNL] [ORNL

    2011-01-01

    Researchers at Oak Ridge National Laboratory (ORNL) developed the Adaptable, Multiplatform, Real-Time Analysis Package (AMRAP) for the continuous measurement of environmental radionuclide decay. AMRAP is a completely open source visualization and analysis package capable of combining a variety of data streams into an array of real-time plots. Once acquired, data streams are analyzed to store static images and extract data based on previously defined thresholds. AMRAP is currently used at ORNL to combine data streams from an Ortec Detective high-purity germanium (HPGe) detector, a TSA Systems radiation portal monitor (RPM), and an Orion weather station. The combined data are used to study the rain-induced increase in RPM background radiation levels. RPMs experience an increase in background radiation during precipitation due to the deposition of atmospheric radionuclides on the ground. Using AMRAP results in a real-time analysis workstation specifically dedicated to the study of RPM background radiation levels. By means of an editable library of common inputs, AMRAP is adaptable to remote monitoring applications that would benefit from the real-time visualization and analysis of radiation measurements. To study rain-induced increases in background radiation levels observed in radiation portal monitors (RPMs), researchers at Oak Ridge National Laboratory (ORNL) developed a software package that allows data with different formats to be analyzed and plotted in near real time. The Adaptable, Multiplatform, Real-Time Analysis Package (AMRAP) was developed to operate in the background and capture plots of important data based on previously defined thresholds. After executing AMRAP, segments of a data stream can be captured without additional post-processing. AMRAP can also display previously recorded data to facilitate a detailed offline analysis. Without access to these capabilities in a single software package, analyzing multiple continuously recorded data streams with different formats is impractical. Commercially available acquisition software packages record and analyze radiation measurements but are not designed to perform real-time analysis in conjunction with data from other vendors. The lack of collaboration between vendors is problematic when research requires different data streams to be correlated in time and immediately analyzed. AMRAP was specifically developed to provide a solution to this problem. AMRAP is a completely open source visualization and analysis package capable of plotting and analyzing data from different vendors in near real time.

  16. Engineering Adaptive Web Applications

    E-Print Network [OSTI]

    Dolog, Peter

    Engineering Adaptive Web Applications Von Fakultt fr Elektrotechnik und Informatik der Peter Dolog Engineering Adaptive Web Applications Dr. rer. nat. Dissertation 2006 #12;#12;Zusammenfassung: Nutzer von Web-Anwendungen stammen sich aus verschiedensten Nut- zergruppen, die sich in ihrem

  17. III International Climate Change Adaptation Adaptation Futures 2014

    E-Print Network [OSTI]

    1 III International Climate Change Adaptation Conference Adaptation Futures 2014 12-16 Maio 2014 sucesso da primeira conferncia Climate Adaptation Futures realizada em Queensland, Austrlia, em 2010 e

  18. Cataractogenic effects of proton radiation

    E-Print Network [OSTI]

    Kyzar, James Ronald

    1972-01-01

    the cyclotron would induce cataracts in the exposed eye (1). In 1949 the National Research Council's Committee on Ophthalmology delegated an investigational team to Japan to study the occurrence of radiation cataracts among atom bomb survivors. This team... for the most part to ophthalmological circles arousing little interest in other elements of the scien- tific world (13) . In the decade of the 1940's conditions arose which were to vastly change research into the area of radiation damage. These conditions...

  19. Radiation Effect On Gas Electron Multiplier Detector Performance...

    Office of Scientific and Technical Information (OSTI)

    found from that additional electrons from radiation-induced free radicals in the Kapton film contribute more to output signal of the irradiated GEM detectors. Further studies...

  20. SU-E-J-153: MRI Based, Daily Adaptive Radiotherapy for Rectal Cancer: Contour Adaptation

    SciTech Connect (OSTI)

    Kleijnen, J; Burbach, M; Verbraeken, T; Weggers, R; Zoetelief, A; Reerink, O; Lagendijk, J; Raaymakers, B; Asselen, B [University Medical Center Utrecht, Utrecht (Netherlands)

    2014-06-01

    Purpose: A major hurdle in adaptive radiotherapy is the adaptation of the planning MRI's delineations to the daily anatomy. We therefore investigate the accuracy and time needed for online clinical target volume (CTV) adaptation by radiation therapists (RTT), to be used in MRI-guided adaptive treatments on a MRI-Linac (MRL). Methods: Sixteen patients, diagnosed with early stage rectal cancer, underwent a T2-weighted MRI prior to each fraction of short-course radiotherapy, resulting in 45 scans per patient. On these scans, the CTV was delineated according to guidelines by an experienced radiation oncologist (RO) and considered to be the gold standard. For each patient, the first MRI was considered as the planning MRI and matched on bony anatomy to the 34 daily MRIs. The planning MRI's CTV delineation was rigidly propagated to the daily MRI scans as a proposal for adaptation. Three RTTs in training started the adaptation of the CTV conform guidelines, after a two hour training lecture and a two patient (n=7) training set. To assess the inter-therapist variation, all three RTTs altered delineations of 3 patients (n=12). One RTT altered the CTV delineations (n=53) of the remaining 11 patients. Time needed for adaptation of the CTV to guidelines was registered.As a measure of agreement, the conformity index (CI) was determined between the RTTs' delineations as a group. Dice similarity coefficients were determined between delineations of the RTT and the RO. Results: We found good agreement between RTTs' and RO's delineations (average Dice=0.91, SD=0.03). Furthermore, the inter-observer agreement between the RTTs was high (average CI=0.94, SD=0.02). Adaptation time reduced from 10:33 min (SD= 3:46) to 2:56 min (SD=1:06) between the first and last ten delineations, respectively. Conclusion: Daily CTV adaptation by RTTs, seems a feasible and safe way to introduce daily, online MRI-based plan adaptation for a MRL.

  1. Modeling the Risk of Radiation-Induced Acute Esophagitis for Combined Washington University and RTOG Trial 93-11 Lung Cancer Patients

    SciTech Connect (OSTI)

    Huang, Ellen X.; Bradley, Jeffrey D.; El Naqa, Issam [Department of Radiation Oncology, Washington University School of Medicine, St Louis, MO (United States); Hope, Andrew J.; Lindsay, Patricia E. [Princess Margaret Hospital, Toronto, ON (Canada); Bosch, Walter R.; Matthews, John W. [Department of Radiation Oncology, Washington University School of Medicine, St Louis, MO (United States); Sause, William T. [Department of Radiation Oncology, LDS Hospital, Salt Lake City, UT (United States); Graham, Mary V. [Department of Radiation Oncology, Phelps County Regional Hospital, Rolla, MO (United States); Deasy, Joseph O., E-mail: deasyj@mskcc.org [Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, NY (United States)

    2012-04-01

    Purpose: To construct a maximally predictive model of the risk of severe acute esophagitis (AE) for patients who receive definitive radiation therapy (RT) for non-small-cell lung cancer. Methods and Materials: The dataset includes Washington University and RTOG 93-11 clinical trial data (events/patients: 120/374, WUSTL = 101/237, RTOG9311 = 19/137). Statistical model building was performed based on dosimetric and clinical parameters (patient age, sex, weight loss, pretreatment chemotherapy, concurrent chemotherapy, fraction size). A wide range of dose-volume parameters were extracted from dearchived treatment plans, including Dx, Vx, MOHx (mean of hottest x% volume), MOCx (mean of coldest x% volume), and gEUD (generalized equivalent uniform dose) values. Results: The most significant single parameters for predicting acute esophagitis (RTOG Grade 2 or greater) were MOH85, mean esophagus dose (MED), and V30. A superior-inferior weighted dose-center position was derived but not found to be significant. Fraction size was found to be significant on univariate logistic analysis (Spearman R = 0.421, p < 0.00001) but not multivariate logistic modeling. Cross-validation model building was used to determine that an optimal model size needed only two parameters (MOH85 and concurrent chemotherapy, robustly selected on bootstrap model-rebuilding). Mean esophagus dose (MED) is preferred instead of MOH85, as it gives nearly the same statistical performance and is easier to compute. AE risk is given as a logistic function of (0.0688 Asterisk-Operator MED+1.50 Asterisk-Operator ConChemo-3.13), where MED is in Gy and ConChemo is either 1 (yes) if concurrent chemotherapy was given, or 0 (no). This model correlates to the observed risk of AE with a Spearman coefficient of 0.629 (p < 0.000001). Conclusions: Multivariate statistical model building with cross-validation suggests that a two-variable logistic model based on mean dose and the use of concurrent chemotherapy robustly predicts acute esophagitis risk in combined-data WUSTL and RTOG 93-11 trial datasets.

  2. RADIATION MONITORING

    E-Print Network [OSTI]

    Thomas, R.H.

    2010-01-01

    Radiation Exposure due to a Boiling Water Reactor Plume fromIN THE VICINITY OF A BOILING WATER REACTOR EXPOSURE RATE

  3. Prospective Study Validating Inter- and Intraobserver Variability of Tissue Compliance Meter in Breast Tissue of Healthy Volunteers: Potential Implications for Patients With Radiation-Induced Fibrosis of the Breast

    SciTech Connect (OSTI)

    Wernicke, A. Gabriella, E-mail: gaw9008@med.cornell.ed [Stich Radiation Oncology, Weill Cornell Medical College of Cornell University, New York, NY (United States); Parashar, Bhupesh; Kulidzhanov, Fridon; Riley, Lillian [Stich Radiation Oncology, Weill Cornell Medical College of Cornell University, New York, NY (United States); Christos, Paul J. [Division of Biostatistics and Epidemiology, Department of Public Health, Weill Cornell Medical College of Cornell University, New York, NY (United States); Fischer, Andrew [Physical Medicine and Rehabilitation, Mount Sinai School of Medicine, New York, NY (United States); Nori, Dattatreyudu; Chao, K.S. Clifford [Stich Radiation Oncology, Weill Cornell Medical College of Cornell University, New York, NY (United States)

    2011-05-01

    Purpose: Accurate detection of radiation-induced fibrosis (RIF) is crucial in management of breast cancer survivors. Tissue compliance meter (TCM) has been validated in musculature. We validate TCM in healthy breast tissue with respect to interobserver and intraobserver variability before applying it in RIF. Methods and Materials: Three medical professionals obtained three consecutive TCM measurements in each of the four quadrants of the right and left breasts of 40 women with no breast disease or surgical intervention. The intraclass correlation coefficient (ICC) assessed interobserver variability. The paired t test and Pearson correlation coefficient (r) were used to assess intraobserver variability within each rater. Results: The median age was 45 years (range, 24-68 years). The median bra size was 35C (range, 32A-40DD). Of the participants, 27 were white (67%), 4 black (10%), 5 Asian (13%), and 4 Hispanic (10%). ICCs indicated excellent interrater reliability (low interobserver variability) among the three raters, by breast and quadrant (all ICC {>=}0.99). The paired t test and Pearson correlation coefficient both indicated low intraobserver variability within each rater (right vs. left breast), stratified by quadrant (all r{>=} 0.94, p < 0.0001). Conclusions: The interobserver and intraobserver variability is small using TCM in healthy mammary tissue. We are now embarking on a prospective study using TCM in women with breast cancer at risk of developing RIF that may guide early detection, timely therapeutic intervention, and assessment of success of therapy for RIF.

  4. Climate Change Adaptation

    Broader source: Energy.gov [DOE]

    DOE is adapting to climate change by applying a risk-based resiliency approach to identify and minimize climate-related vulnerabilities across all DOE policies, programs and activities.

  5. Rethinking adaptive reuse

    E-Print Network [OSTI]

    Benardete, Emma A., 1973-

    2002-01-01

    Adaptive reuse of manufacturing plants in post-industrial countries has become an increasing trend. In the United States, evidence of our industrial past is present in both urban and rural landscapes. The appearance of ...

  6. Postmodern film adaptation

    E-Print Network [OSTI]

    Brannon, Courtney Elizabeth

    2013-02-22

    Chapter one explores the reflexive nature of Stephen Daldry's The Hours (2002) as an adaptation from two previous novels: Virginia Woolf's Mrs. Dalloway and Michael Cunningham's The Hours. Through the motif of mirror images, the film consciously...

  7. Climate Change Adaptation Planning

    Office of Energy Efficiency and Renewable Energy (EERE)

    This course provides an introduction to planning for climate change impacts, with examples of tribes that have been going through the adaptation planning process. The course is intended for tribal...

  8. Radiation Damage in Nanostructured Metallic Films

    E-Print Network [OSTI]

    Yu, Kaiyuan

    2013-04-15

    . Such systems obtain high volume fraction of boundaries, which are considered sinks to radiation induced defects. From the viewpoint of nanomechanics, it is of interest to investigate the plastic deformation mechanisms of nanostructured films, which typically...

  9. Adaptive versus non-adaptive strategies for quantum channel discrimination

    E-Print Network [OSTI]

    Watrous, John

    Adaptive versus non-adaptive strategies for quantum channel discrimination Aram W. Harrow Avinatan-adaptive strategies for quantum channel discrimination. In particular, we give a pair of entanglement- breaking channels that can be perfectly discriminated by means of an adaptive strategy that re- quires just two

  10. Hypochlorous acid and hydrogen peroxide-induced negative regulation of Salmonella enterica serovar Typhimurium ompW by the response regulator ArcA

    E-Print Network [OSTI]

    2012-01-01

    induced negative regulation of Salmonella enterica serovarsuperoxide dismutase in Salmonella. FEMS Microbiol LettAdaptation Sensitizes Salmonella Typhimurium to Hypochlorous

  11. Radiation detector

    DOE Patents [OSTI]

    Fultz, B.T.

    1980-12-05

    Apparatus is provided for detecting radiation such as gamma rays and x-rays generated in backscatter Moessbauer effect spectroscopy and x-ray spectrometry, which has a large window for detecting radiation emanating over a wide solid angle from a specimen and which generates substantially the same output pulse height for monoenergetic radiation that passes through any portion of the detection chamber. The apparatus includes a substantially toroidal chamber with conductive walls forming a cathode, and a wire anode extending in a circle within the chamber with the anode lying closer to the inner side of the toroid which has the least diameter than to the outer side. The placement of the anode produces an electric field, in a region close to the anode, which has substantially the same gradient in all directions extending radially from the anode, so that the number of avalanche electrons generated by ionizing radiation is independent of the path of the radiation through the chamber.

  12. Radiation dosimeter

    DOE Patents [OSTI]

    Fox, R.J.

    1981-09-01

    A radiation detector readout circuit is provided which produces a radiation dose-rate readout from a detector even through the detector output may be highly energy dependent. A linear charge amplifier including an output charge pump circuit amplifies the charge signal pulses from the detector and pumps the charge into a charge storage capacitor. The discharge rate of the capacitor through a resistor is controlled to provide a time-dependent voltage which when integrated provides an output proportional to the dose-rate of radiation detected by the detector. This output may be converted to digital form for readout on a digital display.

  13. Radiation dosimeter

    DOE Patents [OSTI]

    Fox, Richard J. (Oak Ridge, TN)

    1983-01-01

    A radiation detector readout circuit is provided which produces a radiation dose-rate readout from a detector even though the detector output may be highly energy dependent. A linear charge amplifier including an output charge pump circuit amplifies the charge signal pulses from the detector and pumps the charge into a charge storage capacitor. The discharge rate of the capacitor through a resistor is controlled to provide a time-dependent voltage which when integrated provides an output proportional to the dose-rate of radiation detected by the detector. This output may be converted to digital form for readout on a digital display.

  14. Perspectives of Decision-Making and Estimation of Risk in Populations Exposed to Low Levels of Ionizing Radiations

    E-Print Network [OSTI]

    Fabrikant, J.I.

    2010-01-01

    Extrapolation to low doses. Radiation Res. 71: Upton, A.C.for high LET radiations at low doses, risk values may beof radiation-induced leukemia, fow'LET, low dose: 6/rad)

  15. CHEMICAL ACTIONS OF IONIZING RADIATION ON OLIGOPEPTIDE DERIVATIVES OF GLYCINE IN THE NEUTRAL (ZWITTERION) AND BASIC FORMS

    E-Print Network [OSTI]

    Garrison, W.M.

    2010-01-01

    REFERENCES 1. k. M. Garrison, Radiation Induced Reactions ofRev. 3 305 (1972). 2. W. M. Garrison, Radiation Chemistry ofJ. Holian, and W. M. Garrison, Radiation Chemistry of the o-

  16. Radiation Protection Dosimetry Vol. 99, Nos 14, pp. 227232 (2002)

    E-Print Network [OSTI]

    2002-01-01

    227 Radiation Protection Dosimetry Vol. 99, Nos 14, pp. 227232 (2002) Nuclear Technology been accepted dogma that the deleterious effects of ionising radiation such as mutagenesis and carcino particle in a lifetime. Over the past 10 years there have been many reports on radiation-induced bystander

  17. Adaptation and adaptability : expectant design for resilience in coastal urbanity

    E-Print Network [OSTI]

    Ruskeep, Laura A. Delaney (Laura Ashley Delaney)

    2011-01-01

    What is the nature of and possibility for urban resiliency through adaptation? Adaptation implies responsiveness to phenomena that are disruptive to a system's functioning; it is a willful evolution in response to changed ...

  18. Radiation Induced Nanocrystal Formation in Metallic Glasses

    E-Print Network [OSTI]

    Carter, Jesse

    2010-01-14

    diameter up to approximately 100 nm in Cu irradiated Zr55Cu30Al10Ni5. Studies of di raction patterns of irradiated specimens showed nucleation of Cu10Zr7 phases in both specimens, as well as evidence of CuZr2 in Cu50Zr45Ti5 and both CuZr2 and NiZr2 in Zr55...

  19. Atmospheric Radiation Measurement Convective and Orographically Induced

    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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 OutreachProductswsicloudwsiclouddenDVA N C E D B L O O DBiomass and BiofuelsPhysicist47 Industrial1Convective and

  20. CONTRIBUTED Adaptive Stochastic Control

    E-Print Network [OSTI]

    Powell, Warren B.

    sources, many forms of energy storage, and microgrid management (see Fig. 1). Computationally, controlling that are extremely close to optimal. We then address the problem of energy storage (e.g., in a large batteryCONTRIBUTED P A P E R Adaptive Stochastic Control for the Smart Grid The main theme of this paper

  1. Adaptive parallel computing with

    E-Print Network [OSTI]

    Pernet, Clment

    was prototyped #12;Urbana / dec 2009 9 C++ Elision struct Fibonacci { void operator()( int n, a1::Shared_wint1, a1::Shared_rint> sr2 ) { result.write( sr1.read() + sr2.read() ); } } #12;Urbana / dec 2009 10 C;Urbana / dec 2009 3 To mutually adapt application and scheduling Extension to target GPU & MPSoC Kaapi

  2. Adaptive sequential controller

    DOE Patents [OSTI]

    El-Sharkawi, Mohamed A. (Renton, WA); Xing, Jian (Seattle, WA); Butler, Nicholas G. (Newberg, OR); Rodriguez, Alonso (Pasadena, CA)

    1994-01-01

    An adaptive sequential controller (50/50') for controlling a circuit breaker (52) or other switching device to substantially eliminate transients on a distribution line caused by closing and opening the circuit breaker. The device adaptively compensates for changes in the response time of the circuit breaker due to aging and environmental effects. A potential transformer (70) provides a reference signal corresponding to the zero crossing of the voltage waveform, and a phase shift comparator circuit (96) compares the reference signal to the time at which any transient was produced when the circuit breaker closed, producing a signal indicative of the adaptive adjustment that should be made. Similarly, in controlling the opening of the circuit breaker, a current transformer (88) provides a reference signal that is compared against the time at which any transient is detected when the circuit breaker last opened. An adaptive adjustment circuit (102) produces a compensation time that is appropriately modified to account for changes in the circuit breaker response, including the effect of ambient conditions and aging. When next opened or closed, the circuit breaker is activated at an appropriately compensated time, so that it closes when the voltage crosses zero and opens when the current crosses zero, minimizing any transients on the distribution line. Phase angle can be used to control the opening of the circuit breaker relative to the reference signal provided by the potential transformer.

  3. Adaptive versus non-adaptive strategies for quantum channel discrimination

    E-Print Network [OSTI]

    Aram W. Harrow; Avinatan Hassidim; Debbie W. Leung; John Watrous

    2009-09-01

    We provide a simple example that illustrates the advantage of adaptive over non-adaptive strategies for quantum channel discrimination. In particular, we give a pair of entanglement-breaking channels that can be perfectly discriminated by means of an adaptive strategy that requires just two channel evaluations, but for which no non-adaptive strategy can give a perfect discrimination using any finite number of channel evaluations.

  4. A MATHEMATICAL FRAMEWORK FOR THE LINEAR RECONSTRUCTOR PROBLEM IN ADAPTIVE OPTICS

    E-Print Network [OSTI]

    A MATHEMATICAL FRAMEWORK FOR THE LINEAR RECONSTRUCTOR PROBLEM IN ADAPTIVE OPTICS MOODY T. CHU induced by atmospheric turbulence can severely de- grade the performance of an optical imaging system. Adaptive optics refers to the process of removing unwanted wave front distortions in real time, i

  5. A MATHEMATICAL FRAMEWORK FOR THE LINEAR RECONSTRUCTOR PROBLEM IN ADAPTIVE OPTICS

    E-Print Network [OSTI]

    A MATHEMATICAL FRAMEWORK FOR THE LINEAR RECONSTRUCTOR PROBLEM IN ADAPTIVE OPTICS MOODY T. CHU aberrations induced by atmospheric turbulence can severely de­ grade the performance of an optical imaging system. Adaptive optics refers to the process of removing unwanted wave front distortions in real time, i

  6. 7th International Workshop on Microbeam Probes of Cellular Radiation Response

    SciTech Connect (OSTI)

    Brenner, David J.

    2009-07-21

    The extended abstracts that follow present a summary of the Proceedings of the 7th International Workshop: Microbeam Probes of Cellular Radiation Response, held at Columbia Universitys Kellogg Center in New York City on March 1517, 2006. These International Workshops on Microbeam Probes of Cellular Radiation Response have been held regularly since 1993 (15). Since the first workshop, there has been a rapid growth (see Fig. 1) in the number of centers developing microbeams for radiobiological research, and worldwide there are currently about 30 microbeams in operation or under development. Single-cell/single-particle microbeam systems can deliver beams of different ionizing radiations with a spatial resolution of a few micrometers down to a few tenths of a micrometer. Microbeams can be used to addressquestions relating to the effects of low doses of radiation (a single radiation track traversing a cell or group of cells), to probe subcellular targets (e.g. nucleus or cytoplasm), and to address questions regarding the propagation of information about DNA damage (for example, the radiation-induced bystander effect). Much of the recent research using microbeams has been to study low-dose effects and non-targeted responses such as bystander effects, genomic instability and adaptive responses. This Workshop provided a forum to assess the current state of microbeam technology and current biological applications and to discuss future directions for development, both technological and biological. Over 100 participants reviewed the current state of microbeam research worldwide and reported on new technological developments in the fields of both physics and biology.

  7. III International Climate Change Adaptation Adaptation Futures 2014

    E-Print Network [OSTI]

    1 III International Climate Change Adaptation Conference Adaptation Futures 2014 12-16 May 2014 of Research on Climate Change Vulnerability, Impacts and Adaptation (PROVIA), the Co and reports from the conference in newspapers 93 #12;4 1. INTRODUCTION Climate

  8. Evolving Recursive Programs by Using Adaptive Grammar Based Genetic Programming

    E-Print Network [OSTI]

    Fernandez, Thomas

    Page 1 Evolving Recursive Programs by Using Adaptive Grammar Based Genetic Programming Man Leung@ln.edu.hk Abstract Genetic programming (GP) extends traditional genetic algorithms to automatically induce computer programs. GP has been applied in a wide range of applications such as software re- engineering, electrical

  9. Radiation receiver

    DOE Patents [OSTI]

    Hunt, A.J.

    1983-09-13

    The apparatus for collecting radiant energy and converting same to alternate energy form includes a housing having an interior space and a radiation transparent window allowing, for example, solar radiation to be received in the interior space of the housing. Means are provided for passing a stream of fluid past said window and for injecting radiation absorbent particles in said fluid stream. The particles absorb the radiation and because of their very large surface area, quickly release the heat to the surrounding fluid stream. The fluid stream particle mixture is heated until the particles vaporize. The fluid stream is then allowed to expand in, for example, a gas turbine to produce mechanical energy. In an aspect of the present invention properly sized particles need not be vaporized prior to the entrance of the fluid stream into the turbine, as the particles will not damage the turbine blades. In yet another aspect of the invention, conventional fuel injectors are provided to inject fuel into the fluid stream to maintain the proper temperature and pressure of the fluid stream should the source of radiant energy be interrupted. In yet another aspect of the invention, an apparatus is provided which includes means for providing a hot fluid stream having hot particles disbursed therein which can radiate energy, means for providing a cooler fluid stream having cooler particles disbursed therein, which particles can absorb radiant energy and means for passing the hot fluid stream adjacent the cooler fluid stream to warm the cooler fluid and cooler particles by the radiation from the hot fluid and hot particles. 5 figs.

  10. Radiation receiver

    DOE Patents [OSTI]

    Hunt, Arlon J. (Oakland, CA)

    1983-01-01

    The apparatus for collecting radiant energy and converting same to alternate energy form includes a housing having an interior space and a radiation transparent window allowing, for example, solar radiation to be received in the interior space of the housing. Means are provided for passing a stream of fluid past said window and for injecting radiation absorbent particles in said fluid stream. The particles absorb the radiation and because of their very large surface area, quickly release the heat to the surrounding fluid stream. The fluid stream particle mixture is heated until the particles vaporize. The fluid stream is then allowed to expand in, for example, a gas turbine to produce mechanical energy. In an aspect of the present invention properly sized particles need not be vaporized prior to the entrance of the fluid stream into the turbine, as the particles will not damage the turbine blades. In yet another aspect of the invention, conventional fuel injectors are provided to inject fuel into the fluid stream to maintain the proper temperature and pressure of the fluid stream should the source of radiant energy be interrupted. In yet another aspect of the invention, an apparatus is provided which includes means for providing a hot fluid stream having hot particles disbursed therein which can radiate energy, means for providing a cooler fluid stream having cooler particles disbursed therein, which particles can absorb radiant energy and means for passing the hot fluid stream adjacent the cooler fluid stream to warm the cooler fluid and cooler particles by the radiation from the hot fluid and hot particles.

  11. Biologically Guided Radiation Therapy (BGRT)Biologically Guided Radiation Therapy (BGRT) Effects InterEffects Inter Patient andPatient andEffects InterEffects Inter--Patient andPatient and

    E-Print Network [OSTI]

    Stewart, Robert D.

    ss 77 CancerCancer HeritableHeritable EffectsEffects Germline 101055 ss Self renewal Stewart, JH Park, DJ Carlson, Isoeffect Calculations in Adaptive Radiation TherapyRD Stewart, JH Park, DJ Carlson, Isoeffect Calculations in Adaptive Radiation Therapy and Treatment Individualization, Inand

  12. Climate Change, Adaptation, and Development

    E-Print Network [OSTI]

    Cole, Daniel H.

    2008-01-01

    Climate Change, Adaptation, and Development Daniel H. Cole*THE COSTS OF CLIMATE CHANGE . ADAPTATIONCONVENTION ON CLIMATE CHANGE . IV. A.

  13. Adaptive Finite Elements and Colliding Black Holes

    E-Print Network [OSTI]

    Douglas N. Arnold; Arup Mukherjee; Luc Pouly

    1997-09-15

    According to the theory of general relativity, the relative acceleration of masses generates gravitational radiation. Although gravitational radiation has not yet been detected, it is believed that extremely violent cosmic events, such as the collision of black holes, should generate gravity waves of sufficient amplitude to detect on earth. The massive Laser Interferometer Gravitational-wave Observatory, or LIGO, is now being constructed to detect gravity waves. Consequently there is great interest in the computer simulation of black hole collisions and similar events, based on the numerical solution of the Einstein field equations. In this note we introduce the scientific, mathematical, and computational problems and discuss the development of a computer code to solve the initial data problem for colliding black holes, a nonlinear elliptic boundary value problem posed in an unbounded three dimensional domain which is a key step in solving the full field equations. The code is based on finite elements, adaptive meshes, and a multigrid solution process. Here we will particularly emphasize the mathematical and algorithmic issues arising in the generation of adaptive tetrahedral meshes.

  14. Transforming Growth Factor ?-1 (TGF-?1) Is a Serum Biomarker of Radiation Induced Fibrosis in Patients Treated With Intracavitary Accelerated Partial Breast Irradiation: Preliminary Results of a Prospective Study

    SciTech Connect (OSTI)

    Boothe, Dustin L.; Coplowitz, Shana; Greenwood, Eleni; Barney, Christian L.; Christos, Paul J.; Parashar, Bhupesh; Nori, Dattatreyudu; Chao, K. S. Clifford; Wernicke, A. Gabriella

    2013-12-01

    Purpose: To examine a relationship between serum transforming growth factor ? -1 (TGF-?1) values and radiation-induced fibrosis (RIF). Methods and Materials: We conducted a prospective analysis of the development of RIF in 39 women with American Joint Committee on Cancer stage 0-I breast cancer treated with lumpectomy and accelerated partial breast irradiation via intracavitary brachytherapy (IBAPBI). An enzyme-linked immunoassay (Quantikine, R and D, Minneapolis, MN) was used to measure serum TGF-?1 before surgery, before IBAPBI, and during IBAPBI. Blood samples for TGF-?1 were also collected from 15 healthy, nontreated women (controls). The previously validated tissue compliance meter (TCM) was used to objectively assess RIF. Results: The median time to follow-up for 39 patients was 44 months (range, 5-59 months). RIF was graded by the TCM scale as 0, 1, 2, and 3 in 5 of 20 patients (25%), 6 of 20 patients (30%), 5 of 20 patients (25%), and 4 of 20 patients (20%), respectively. The mean serum TGF-?1 values were significantly higher in patients before surgery than in disease-free controls, as follows: all cancer patients (30,201 5889 pg/mL, P=.02); patients with any type of RIF (32,273 5016 pg/mL, P<.0001); and women with moderate to severe RIF (34,462 4713 pg/mL, P<0.0001). Patients with moderate to severe RIF had significantly elevated TGF-?1 levels when compared with those with none to mild RIF before surgery (P=.0014) during IBAPBI (P?0001), and the elevation persisted at 6 months (P?.001), 12 months (P?.001), 18 months (P?.001), and 24 months (P=.12). A receiver operating characteristic (ROC) curve of TGF-?1 values predicting moderate to severe RIF was generated with an area under the curve (AUC){sub ROC} of 0.867 (95% confidence interval 0.700-1.000). The TGF-?1 threshold cutoff was determined to be 31,000 pg/mL, with associated sensitivity and specificity of 77.8% and 90.0%, respectively. Conclusions: TGF-?1 levels correlate with the development of moderate to severe RIF. The pre-IBAPBI mean TGF-?1 levels can serve as an early biomarker for the development of moderate to severe RIF after IBAPBI.

  15. Adaptive control for accelerators

    DOE Patents [OSTI]

    Eaton, Lawrie E. (Los Alamos, NM); Jachim, Stephen P. (Los Alamos, NM); Natter, Eckard F. (Santa Fe, NM)

    1991-01-01

    An adaptive feedforward control loop is provided to stabilize accelerator beam loading of the radio frequency field in an accelerator cavity during successive pulses of the beam into the cavity. A digital signal processor enables an adaptive algorithm to generate a feedforward error correcting signal functionally determined by the feedback error obtained by a beam pulse loading the cavity after the previous correcting signal was applied to the cavity. Each cavity feedforward correcting signal is successively stored in the digital processor and modified by the feedback error resulting from its application to generate the next feedforward error correcting signal. A feedforward error correcting signal is generated by the digital processor in advance of the beam pulse to enable a composite correcting signal and the beam pulse to arrive concurrently at the cavity.

  16. Radiation Protection Act (Pennsylvania)

    Broader source: Energy.gov [DOE]

    This Act combines the radiation safety provisions of The Atomic Energy Development and Radiation Control Act and the Environmental Radiation Protection Act, and empowers the Department of...

  17. DETECTORS FOR RADIATION DOSIMETRY

    E-Print Network [OSTI]

    Perez-Mendez, V.

    2010-01-01

    I. Applications of Radiation Detectors 1) X-Rays, Gammaof the Conference DETECTORS FOR RADIATION DOSIMETRY VictorT E D LBL9651 DETECTORS FOR RADIATION DOSIMETRY - DISCLAIM*

  18. Historical biogeography and ecological opportunity in the adaptive radiation

    E-Print Network [OSTI]

    O'Grady, Patrick M.

    ), with a basal divergence in Hawaii 3.2 Ma. Histori- cal biogeographical reconstructions reveal a Kauai origin endemic to Kauai are significantly clustered with respect to the whole phylogeny; however, species show colonized the Hawaiian Islands after the for- mation of Kauai. Host plant arrival times and insect

  19. Intrinsic radiation resistance in human chondrosarcoma cells

    SciTech Connect (OSTI)

    Moussavi-Harami, Farid [Departments of Orthopaedics and Rehabilitation, University of Iowa, Iowa City, IA 52242 (United States); Mollano, Anthony [Departments of Orthopaedics and Rehabilitation, University of Iowa, Iowa City, IA 52242 (United States); Martin, James A. [Departments of Orthopaedics and Rehabilitation, University of Iowa, Iowa City, IA 52242 (United States); Ayoob, Andrew [Departments of Orthopaedics and Rehabilitation, University of Iowa, Iowa City, IA 52242 (United States); Domann, Frederick E. [Department of Radiation Oncology, Iowa City, IA 52245 (United States); Gitelis, Steven [Department of Internal Medicine, Section of Medical Oncology, Chicago, IL 60612 (United States); Department of Orthopaedics Rush-Presbyterian St. Luke's Medical Center, Chicago, IL 60612 (United States); Buckwalter, Joseph A. [Departments of Orthopaedics and Rehabilitation, University of Iowa, Iowa City, IA 52242 (United States)]. E-mail: joseph-buckwalter@uiowa.edu

    2006-07-28

    Human chondrosarcomas rarely respond to radiation treatment, limiting the options for eradication of these tumors. The basis of radiation resistance in chondrosarcomas remains obscure. In normal cells radiation induces DNA damage that leads to growth arrest or death. However, cells that lack cell cycle control mechanisms needed for these responses show intrinsic radiation resistance. In previous work, we identified immortalized human chondrosarcoma cell lines that lacked p16{sup ink4a}, one of the major tumor suppressor proteins that regulate the cell cycle. We hypothesized that the absence of p16{sup ink4a} contributes to the intrinsic radiation resistance of chondrosarcomas and that restoring p16{sup ink4a} expression would increase their radiation sensitivity. To test this we determined the effects of ectopic p16{sup ink4a} expression on chondrosarcoma cell resistance to low-dose {gamma}-irradiation (1-5 Gy). p16{sup ink4a} expression significantly increased radiation sensitivity in clonogenic assays. Apoptosis did not increase significantly with radiation and was unaffected by p16{sup ink4a} transduction of chondrosarcoma cells, indicating that mitotic catastrophe, rather than programmed cell death, was the predominant radiation effect. These results support the hypothesis that p16{sup ink4a} plays a role in the radiation resistance of chondrosarcoma cell lines and suggests that restoring p16 expression will improve the radiation sensitivity of human chondrosarcomas.

  20. Stellar feedback by radiation pressure and photoionization

    E-Print Network [OSTI]

    Sales, Laura V; Springel, Volker; Petkova, Margarita

    2013-01-01

    The relative impact of radiation pressure and photoionization feedback from young stars on surrounding gas is studied with hydrodynamic radiative transfer (RT) simulations. The calculations focus on the single-scattering (direct radiation pressure) and optically thick regime, and adopt a moment-based RT-method implemented in the moving-mesh code AREPO. The source luminosity, gas density profile and initial temperature are varied. At typical temperatures and densities of molecular clouds, radiation pressure drives velocities of order ~20 km/s over 1-5 Myr; enough to unbind the smaller clouds. However, these estimates ignore the effects of photoionization that naturally occur concurrently. When radiation pressure and photoionization act together, the latter is substantially more efficient, inducing velocities comparable to the sound speed of the hot ionized medium (10-15 km/s) on timescales far shorter than required for accumulating similar momentum with radiation pressure. This mismatch allows photoionization ...

  1. Radiative energy loss and radiative p_T-broadening of high-energy partons in QCD matter

    E-Print Network [OSTI]

    Wu, Bin

    2015-01-01

    I give a self-contained review on radiative p_T-broadening and radiative energy loss of high-energy partons in QCD matter. The typical p_T^2 of high-energy partons receives a double logarithmic correction due to the recoiling effect of medium-induced gluon radiation. Such a double logarithmic term, averaged over the path length of the partons, can be taken as the radiative correction to the jet quenching parameter qhat and hence contributes to radiative energy loss. This has also been confirmed by detailed calculations of energy loss by radiating two gluons.

  2. Radiation-hardened polymeric films

    DOE Patents [OSTI]

    Arnold, C. Jr.; Hughes, R.C.; Kepler, R.G.; Kurtz, S.R.

    1984-07-16

    The radiation-induced conductivity of polymeric dielectrics with low electronic mobility is reduced by doping with electron donor or electron acceptor compounds at a level of 10/sup 15/ to 10/sup 21/ molecules of dopant/cm/sup 3/. Polyesters, polyolefins, perfluoropolyolefins, vinyl polymers, vinylidene polymers, polycarbonates, polysulfones and polyimides can benefit from such a treatment. Usable dopants include 2,4,7-trinitro-9-fluorenone, tetracyanethylene, 7,7,8,8-tetracyanoquinodimethane, m-dinitrobenzene, 2-isopropylcarbazole, and triphenylamine.

  3. Radiation-hardened polymeric films

    DOE Patents [OSTI]

    Arnold, Jr., Charles (Albuquerque, NM); Hughes, Robert C. (Albuquerque, NM); Kepler, R. Glen (Albuquerque, NM); Kurtz, Steven R. (Albuquerque, NM)

    1986-01-01

    The radiation-induced conductivity of polymeric dielectrics with low electronic mobility is reduced by doping with electron donor or electron acceptor compounds at a level of 10.sup.15 to 10.sup.21 molecules of dopant/cm.sup.3. Polyesters, polyolefins, perfluoropolyolefins, vinyl polymers, vinylidene polymers, polycarbonates, polysulfones and polyimides can benefit from such a treatment. Usable dopants include 2,4,7-trinitro-9-fluorenone, tetracyanethylene, 7,7,8,8-tetracyanoquinodimethane, m-dinitrobenzene, 2-isopropylcarbazole, and triphenylamine.

  4. Axion Induced Oscillating Electric Dipole Moment of the Electron

    E-Print Network [OSTI]

    Christopher T. Hill

    2015-09-28

    The axion electromagnetic anomaly induces an oscillating electric dipole for the electron of frequency $m_a$ and strength $\\sim 10^{-32}$ e-cm, two orders of magnitude above the nucleon, and within four orders of magnitude of the present standard model constant limit. We give a detailed study of this phenomenon via the interaction of the cosmic axion, through the electromagnetic anomaly, with particular emphasis on the decoupling limit of the axion, $\\partial_t a(t)\\propto m_a \\rightarrow 0$. The general form of the action involves a local contact interaction and a nonlocal contribution that enforces the decoupling limit. We derive the effective action in the Pauli-Schroedinger non-relativistic formalism, and in Georgi's heavy quark formalism adapted to the "heavy electron" (heavy compared to $m_a$). We compute the electric dipole radiation emitted by stationary electrons, and we discuss a number of experimental configurations that may yield detectable signals. Phased array radiators with $N^2$ unit cell magnetic elements may have advantages over resonant cavities that exploit large $Q$, since we can design toward $N^2 >> Q$.

  5. Adaptive computation of gravitational waves from black hole interactions

    E-Print Network [OSTI]

    Philippos Papadopoulos; Edward Seidel; Lee Wild

    1998-02-27

    We construct a class of linear partial differential equations describing general perturbations of non-rotating black holes in 3D Cartesian coordinates. In contrast to the usual approach, a single equation treats all radiative $\\ell -m$ modes simultaneously, allowing the study of wave perturbations of black holes with arbitrary 3D structure, as would be present when studying the full set of nonlinear Einstein equations describing a perturbed black hole. This class of equations forms an excellent testbed to explore the computational issues of simulating black spacetimes using a three dimensional adaptive mesh refinement code. Using this code, we present results from the first fully resolved 3D solution of the equations describing perturbed black holes. We discuss both fixed and adaptive mesh refinement, refinement criteria, and the computational savings provided by adaptive techniques in 3D for such model problems of distorted black holes.

  6. Predator induced defenses in prey with diverse predators

    E-Print Network [OSTI]

    Garza, Mark Isaac

    2006-04-12

    Phenotypic plasticity is an environmentally based change in phenotype and can be adaptive. Often, the change in an organism's phenotype is induced by the presence of a predator and serves as a defense against that predator. Defensive phenotypes...

  7. Quantum metric fluctuations and Hawking radiation

    E-Print Network [OSTI]

    R. Parentani

    2000-09-05

    In this Letter we study the gravitational interactions between outgoing configurations giving rise to Hawking radiation and in-falling configurations. When the latter are in their ground state, the near horizon interactions lead to collective effects which express themselves as metric fluctuations and which induce dissipation, as in Brownian motion. This dissipation prevents the appearance of trans-Planckian frequencies and leads to a description of Hawking radiation which is very similar to that obtained from sound propagation in condensed matter models.

  8. Predicting the radiation tolerance of oxides

    SciTech Connect (OSTI)

    Sickafus, K. (Kurt E.); Grimes, R. W. (Robin W.)

    2001-01-01

    We have used atomistic computer simulations and ion beam irradiations to examine radiation damage accumulation in multicomponent oxides, We have developed contour energy maps via computer simulations to predict the effects of oxide structure and chemical composition on radiation-induced atomic disorder, defect migration, and swelling. Ion irradiation damage experiments have been perfonned on, pyrochlore and fluorite-structured oxide ceramics to test the predictions from computer models.

  9. Radiation Safety

    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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration wouldMassR&D100 Winners * Impacts on GlobalRachel Ruggirello RachelRadiation DrySafety Home

  10. Systematic identification of genes and transduction pathways involved in radio-adaptive response

    SciTech Connect (OSTI)

    Wu, Honglu

    2015-05-22

    Low doses of radiation have been shown to protect against the biological effects of later exposure to toxic levels of radiation. In this study, we propose to identify the molecular mechanisms of this adaptive response by systematically identifying the genes that play a role in radio-protection. In the original proposal, a human cell line that is well-documented to exhibit the radio-adaptive effect was to be used. In this revised study plan, we will use a mouse model, C57BL/6, which has also been well investigated for radio-adaptation. The goal of the proposed study is to enhance our understanding of cellular responses to low doses of radiation exposure at the molecular level.

  11. Normal shock solutions to the viscous shock layer equations including thermal, chemical, thermodynamic, and radiative nonequilibrium

    E-Print Network [OSTI]

    Mott, David Ray

    1993-01-01

    An existing axisymmetric body viscous shock layer code including chemical, thermal, and thermodynamic nonequilibrium and nonequilibrium radiative gasdynamic coupling is adapted to simulate the one-dimensional flow within a shock tube. A suitable...

  12. The optimal thermo-optical properties and energy saving potential of adaptive glazing technologies

    E-Print Network [OSTI]

    Favoino, Fabio; Overend, Mauro; Jin, Qian

    2015-06-17

    system can be self-powered. An evolution of PEC is represented by photo-volta-chromic (PVC), which differs from PEC in that the photovoltaic and electrochromic functions can be separated, thereby facilitating its integration with building management sys... of adaptive or Responsive Building Elements and systems, which passively or actively adjust their thermo-optical properties or operation in a reversible way in order to adapt to changing outdoor/indoor environmental conditions (i.e. solar radiation, air...

  13. Adaptation, Learning, and Optimization over

    E-Print Network [OSTI]

    California at Los Angeles, University of

    Adaptation, Learning, and Optimization over Networks Ali H. Sayed University of California at Los 2014 A. H. Sayed DOI: 10.1561/2200000051 Adaptation, Learning, and Optimization over Networks Ali H . . . . . . . . . . . . . . . . . . . . . . . . . 7 1.6 Notation and Symbols . . . . . . . . . . . . . . . . . . . . 8 2 Optimization by Single Agents

  14. Adaptive Signal Processing Course Information

    E-Print Network [OSTI]

    Tsakalides, Panagiotis

    of the theory to a variety of practical problems such as interference and echo cancellation, signal and system least squares adaptive algorithms 2 Properties of RLS 2 Applications: ADPCM speech encoding Non-Linear. Understanding of the theoretical foundations of adaptive signal processing theory will be achieved through

  15. Radiation dosimeters

    DOE Patents [OSTI]

    Hoelsher, James W. (Pullman, WA); Hegland, Joel E. (Pullman, WA); Braunlich, Peter F. (Pullman, WA); Tetzlaff, Wolfgang (Pullman, WA)

    1992-01-01

    Radiation dosimeters and dosimeter badges. The dosimeter badges include first and second parts which are connected to join using a securement to produce a sealed area in which at least one dosimeter is held and protected. The badge parts are separated to expose the dosimeters to a stimulating laser beam used to read dose exposure information therefrom. The badge is constructed to allow automated disassembly and reassembly in a uniquely fitting relationship. An electronic memory is included to provide calibration and identification information used during reading of the dosimeter. Dosimeter mounts which reduce thermal heating requirements are shown. Dosimeter constructions and production methods using thin substrates and phosphor binder-layers applied thereto are also taught.

  16. Radiation pressure effects in a suspended Fabry-Perot cavity

    E-Print Network [OSTI]

    Pelc, Jason, 1984-

    2006-01-01

    We report on experimental observation of radiation-pressure induced effects in a high-power optical cavity. These effects play an important role in next generation gravitational wave detectors, as well as quantum non-demolition ...

  17. Subject Title: EMF Radiation Safety Program at the

    E-Print Network [OSTI]

    Chan, Hue Sun

    of retinal #12;Subject Title: EMF Radiation Safety Program at the University of Toronto Issued by: Senior, such as cognitive processing, can be affected by induced electric fields below the threshold for direct stimulation

  18. Adaptive Optics in Star Formation

    E-Print Network [OSTI]

    Wolfgang Brandner

    2003-09-29

    Over the past ten years, the concept of adaptive optics has evolved from early experimental stages to a standard observing tool now available at almost all major optical and near-infrared telescope facilities. Adaptive optics will also be essential in exploiting the full potential of the large optical/infrared interferometers currently under construction. Both observations with high-angular resolution and at high contrast, and with a high point source sensitivity are facilitated by adaptive optics. Among the areas which benefit most from the use of adaptive optics are studies of the circumstellar environment (envelopes, disks, outflows), substellar companions and multiple systems, and dense young stellar populations. This contribution highlights some of the recent advances in star formation studies facilitated by adaptive optics, and gives a brief tutorial on optimized observing and data reduction strategies.

  19. THE RADIATION CHEMISTRY OP AMINO ACIDS, PEPTIDES AND PROTEINS IN RELATION TO THE RADIATION STERILIZATION OF HIGH-PROTEIN FOODS

    E-Print Network [OSTI]

    Garrison, W.M.

    2010-01-01

    4^ 43 (1968). W. M. Garrison, Radiation Induced Reactions ofH. A. Sokol, and W. M. Garrison, Radiolytic Cleavage of the40 622 (1970). W. M. Garrison, M. E. Jayko, B. M. Weeks, H.

  20. Method and devices for performing stereotactic microbeam radiation therapy

    DOE Patents [OSTI]

    Dilmanian, F. Avraham (Yaphank, NY)

    2010-01-05

    A radiation delivery system generally includes either a synchrotron source or a support frame and a plurality of microbeam delivery devices supported on the support frame, both to deliver a beam in a hemispherical arrangement. Each of the microbeam delivery devices or synchrotron irradiation ports is adapted to deliver at least one microbeam of radiation along a microbeam delivery axis, wherein the microbeam delivery axes of the plurality of microbeam delivery devices cross within a common target volume.

  1. Low energy electron bombardment induced surface contamination of Ru mirrors

    E-Print Network [OSTI]

    Harilal, S. S.

    Low energy electron bombardment induced surface contamination of Ru mirrors A. Al-Ajlonya , A., Albany, NY 12203, USA ABSTRACT The impact of secondary electrons induced contamination of the Ru surface, carbon contamination, Ruthenium capping 1. INTRODUCTION Extreme ultraviolet (EUV) radiation induced

  2. DETECTORS FOR RADIATION DOSIMETRY

    E-Print Network [OSTI]

    Perez-Mendez, V.

    2010-01-01

    J. Price, "Nuclear Radiation Detection" (2nd ed. , New York:4) G. F. Knoll, "Radiation Detection and Measurement" (NewSons, Inc. from "Radiation Detection and Measurement," G. F.

  3. Radiation Control (Virginia)

    Broader source: Energy.gov [DOE]

    The Department of Health is responsible for regulating radiation and radioactive materials in the Commonwealth of Virginia. Although the Department's Radiation Control Program primarily focuses on...

  4. RADIATIVE AND PASSIVE COOLING

    E-Print Network [OSTI]

    Martin, M.

    2011-01-01

    Ext. 6782 Radiative and Passive Cooling Marlo Martin andof the Second Nation- al Passive Solar Conference (owned rights. ,I I RADIATIVE AND PASSIVE COOLING* LAIVRENCE

  5. A Dynamic Platform for Runtime Adaptation

    E-Print Network [OSTI]

    Pham, Hubert

    We present a middleware platform for assembling pervasive applications that demand fault-tolerance and adaptivity in distributed, dynamic environments. Unlike typical adaptive middleware approaches, in which sophisticated ...

  6. Method for increased sensitivity of radiation detection and measurement

    DOE Patents [OSTI]

    Miller, Steven D. (Richland, WA)

    1994-01-01

    Dose of radiation to which a body of crystalline material has been exposed is measured by exposing the body to optical radiation at a first wavelength, which is greater than about 540 nm, and measuring optical energy emitted from the body by luminescence at a second wavelength, which is longer than the first wavelength. Reduced background is accomplished by more thorough annealing and enhanced radiation induced luminescence is obtained by treating the crystalline material to coalesce primary damage centers into secondary damage centers.

  7. LOW TEMPERATURE PHYSICS RADIATION EFFECTS ON HIGH

    E-Print Network [OSTI]

    McDonald, Kirk

    LOW TEMPERATURE PHYSICS RADIATION EFFECTS ON HIGH TEMPERATURE SUPERCONDUCTORS Harald W. Weber-induced Defects in HTS Practical Materials HTS4Fusion Conductor Workshop, KIT, 27 May 2011 #12;LOW TEMPERATURE;LOW TEMPERATURE PHYSICS Options / Materials "Demo" design (magnetic field, temperature, fluence

  8. Radiation Protection and Licensing FNAL Radiation Physics Team

    E-Print Network [OSTI]

    McDonald, Kirk

    (ALARA). January 13, 2012 Radiation Protection and Licensing #12;4 Shielding for Prompt Radiation Protect

  9. Adaptive multiconfigurational wave functions

    SciTech Connect (OSTI)

    Evangelista, Francesco A.

    2014-03-28

    A method is suggested to build simple multiconfigurational wave functions specified uniquely by an energy cutoff ?. These are constructed from a model space containing determinants with energy relative to that of the most stable determinant no greater than ?. The resulting ?-CI wave function is adaptive, being able to represent both single-reference and multireference electronic states. We also consider a more compact wave function parameterization (?+SD-CI), which is based on a small ?-CI reference and adds a selection of all the singly and doubly excited determinants generated from it. We report two heuristic algorithms to build ?-CI wave functions. The first is based on an approximate prescreening of the full configuration interaction space, while the second performs a breadth-first search coupled with pruning. The ?-CI and ?+SD-CI approaches are used to compute the dissociation curve of N{sub 2} and the potential energy curves for the first three singlet states of C{sub 2}. Special attention is paid to the issue of energy discontinuities caused by changes in the size of the ?-CI wave function along the potential energy curve. This problem is shown to be solvable by smoothing the matrix elements of the Hamiltonian. Our last example, involving the Cu{sub 2}O{sub 2}{sup 2+} core, illustrates an alternative use of the ?-CI method: as a tool to both estimate the multireference character of a wave function and to create a compact model space to be used in subsequent high-level multireference coupled cluster computations.

  10. Radiation therapy of pediatric brain tumors : comparison of long-term health effects and costs between proton therapy and IMRT

    E-Print Network [OSTI]

    Vu, An T. (An Thien)

    2011-01-01

    Radiation therapy is an important component of pediatric brain tumor treatment. However, radiation-induced damage can lead to adverse long-term health effects. Proton therapy has the ability to reduce the dose delivered ...

  11. Automating component reuse and adaptation

    E-Print Network [OSTI]

    Alexander, Perry; Morel, B.

    2004-09-01

    framework for automating specification-based component retrieval and adaptation that has been successfully applied to synthesis of software for embedded and digital signal processing systems. Using specifications to abstractly represent implementations...

  12. Standard Templates Adaptive Parallel Library

    E-Print Network [OSTI]

    Arzu, Francisco Jose

    2000-01-01

    STAPL (Standard Templates Adaptive Parallel Library) is a parallel C++ library designed as a superset of the C++ Standard Template Library (STL), sequentially consistent for functions with the same name, and executed on uni- or multi- processor...

  13. COMMENTARY:Limits to adaptation

    SciTech Connect (OSTI)

    Preston, Benjamin L

    2013-01-01

    An actor-centered, risk-based approach to defining limits to social adaptation provides a useful analytic framing for identifying and anticipating these limits and informing debates over society s responses to climate change.

  14. Microscreen radiation shield for thermoelectric generator

    DOE Patents [OSTI]

    Hunt, Thomas K. (Ann Arbor, MI); Novak, Robert F. (Farmington Hills, MI); McBride, James R. (Ypsilanti, MI)

    1990-01-01

    The present invention provides a microscreen radiation shield which reduces radiative heat losses in thermoelectric generators such as sodium heat engines without reducing the efficiency of operation of such devices. The radiation shield is adapted to be interposed between a reaction zone and a means for condensing an alkali metal vapor in a thermoelectric generator for converting heat energy directly to electrical energy. The radiation shield acts to reflect infrared radiation emanating from the reaction zone back toward the reaction zone while permitting the passage of the alkali metal vapor to the condensing means. The radiation shield includes a woven wire mesh screen or a metal foil having a plurality of orifices formed therein. The orifices in the foil and the spacing between the wires in the mesh is such that radiant heat is reflected back toward the reaction zone in the interior of the generator, while the much smaller diameter alkali metal atoms such as sodium pass directly through the orifices or along the metal surfaces of the shield and through the orifices with little or no impedance.

  15. DETECTORS FOR RADIATION DOSIMETRY

    E-Print Network [OSTI]

    Perez-Mendez, V.

    2010-01-01

    RPL) The interaction of radiation with matter in crystallineradiation. Some interactions with crystalline matter are

  16. RADIATION EFFECTS IN MATERIAL MICROSTRUCTURE.

    SciTech Connect (OSTI)

    SIMOS,N.

    2007-05-30

    Next generation nuclear power systems, high-power particle accelerators and space technology will inevitably rely on higher performance materials that will be able to function in the extreme environments of high irradiation, high temperatures, corrosion and stress. The ability of any material to maintain its functionality under exposure to harsh conditions is directly linked to the material structure at the nano- and micro-scales. Understanding of the underlying processes is key to the success of such undertakings. This paper presents experimental results of the effects of radiation exposure on several unique alloys, composites and crystals through induced changes in the physio-mechanical macroscopic properties.

  17. Optimal Adaptive Waveform Selection for Target Tracking

    E-Print Network [OSTI]

    Rezaeian, Mohammad-Jafar

    seeking to detect submarine periscopes in the presence of sea clutter. The simplest scheme for adaptive

  18. Climate Change Adaptation for Local Government

    E-Print Network [OSTI]

    Pedersen, Tom

    Climate Change Adaptation for Local Government A Resource Guide June 2011 Jenny Fraser, Adaptation Specialist, Climate Action Secretariat, BC Ministry of Environment & Matthew Strand, Researcher, Adaptation to Climate Change Team, Simon Fraser University #12;Page 1 of 26 Climate Change Adaptation for Local

  19. Adaptive Network Defense Management for Countering Smart Attack and Selective Capture

    E-Print Network [OSTI]

    Cao, Yong

    , humidity, tempera- ture, electrical characteristics, and radiation. Smart City [46]: A query-based WSN1 Adaptive Network Defense Management for Countering Smart Attack and Selective Capture in Wireless network defense management for countering smart attack and se- lective capture which aim to cripple

  20. Evaluating aerosol direct radiative effects on global terrestrial ecosystem carbon dynamics from

    E-Print Network [OSTI]

    Zhuang, Qianlai

    loading normally induces lower solar energy arriving at the land surface whereas plant photosynthesis of diffuse solar radiation for plant carbon uptake. Comparing with direct-beam solar radiation, diffuse solar to quantify aerosol effects on downward solar radiation. Simulations with and without considering the aerosol

  1. Adaptive Liquid Crystal Windows

    SciTech Connect (OSTI)

    Taheri, Bahman; Bodnar, Volodymyr

    2011-12-31

    Energy consumption by private and commercial sectors in the U.S. has steadily grown over the last decade. The uncertainty in future availability of imported oil, on which the energy consumption relies strongly, resulted in a dramatic increase in the cost of energy. About 20% of this consumption are used to heat and cool houses and commercial buildings. To reduce dependence on the foreign oil and cut down emission of greenhouse gases, it is necessary to eliminate losses and reduce total energy consumption by buildings. To achieve this goal it is necessary to redefine the role of the conventional windows. At a minimum, windows should stop being a source for energy loss. Ideally, windows should become a source of energy, providing net gain to reduce energy used to heat and cool homes. It is possible to have a net energy gain from a window if its light transmission can be dynamically altered, ideally electronically without the need of operator assistance, providing optimal control of the solar gain that varies with season and climate in the U.S. In addition, the window must not require power from the building for operation. Resolution of this problem is a societal challenge and of national interest and will have a broad global impact. For this purpose, the year-round, allclimate window solution to provide an electronically variable solar heat gain coefficient (SHGC) with a wide dynamic range is needed. AlphaMicron, Inc. (AMI) developed and manufactured 1ft 1ft prototype panels for the worlds first auto-adjusting Adaptive Liquid Crystal Windows (ALCWs) that can operate from sunlight without the need for external power source and demonstrate an electronically adjustable SHGC. This novel windows are based on AlphaMicrons patented e-Tint technology, a guesthost liquid crystal system implemented on flexible, optically clear plastic films. This technology is suitable both for OEM and aftermarket (retro-fitting) lamination to new and existing windows. Low level of power consumption by ALCWs allows for on-board power electronics for automatic matching of transmission through windows to varying climate conditions without drawing the power from the power grid. ALCWs are capable of transmitting more sunlight in winters to assist in heating and less sunlight in summers to minimize overheating. As such, they can change the window from being a source of energy loss to a source of energy gain. In addition, the scalable AMIs roll-to-roll process, proved by making 1ft 1ftALCW prototype panels, allows for cost-effective production of large-scale window panels along with capability to change easily their color and shape. In addition to architectural glazing in houses and commercial buildings, ALCWs can be used in other applications where control of sunlight is needed, such as green houses, used by commercial produce growers and botanical gardens, cars, aircrafts, etc.

  2. Damage-tolerant nanotwinned metals with nanovoids under radiation environments

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

    Chen, Y.; Yu, K. Y.; Liu, Y.; Shao, S.; Wang, H.; Kirk, M. A.; Wang, J.; Zhang, X.

    2015-04-24

    Material performance in extreme radiation environments is central to the design of future nuclear reactors. Radiation induces significant damage in the form of dislocation loops and voids in irradiated materials, and continuous radiation often leads to void growth and subsequent void swelling in metals with low stacking fault energy. Here we show that by using in situ heavy ion irradiation in a transmission electron microscope, pre-introduced nanovoids in nanotwinned Cu efficiently absorb radiation-induced defects accompanied by gradual elimination of nanovoids, enhancing radiation tolerance of Cu. In situ studies and atomistic simulations reveal that such remarkable self-healing capability stems from highmoredensity of coherent and incoherent twin boundaries that rapidly capture and transport point defects and dislocation loops to nanovoids, which act as storage bins for interstitial loops. This study describes a counterintuitive yet significant concept: deliberate introduction of nanovoids in conjunction with nanotwins enables unprecedented damage tolerance in metallic materials.less

  3. Operational Radiation Protection in High-Energy Physics Accelerators

    SciTech Connect (OSTI)

    Rokni, S.H.; Fasso, A.; Liu, J.C.; /SLAC

    2012-04-03

    An overview of operational radiation protection (RP) policies and practices at high-energy electron and proton accelerators used for physics research is presented. The different radiation fields and hazards typical of these facilities are described, as well as access control and radiation control systems. The implementation of an operational RP programme is illustrated, covering area and personnel classification and monitoring, radiation surveys, radiological environmental protection, management of induced radioactivity, radiological work planning and control, management of radioactive materials and wastes, facility dismantling and decommissioning, instrumentation and training.

  4. Training Adaptive Decision-Making.

    SciTech Connect (OSTI)

    Abbott, Robert G.; Forsythe, James C.

    2014-10-01

    Adaptive Thinking has been defined here as the capacity to recognize when a course of action that may have previously been effective is no longer effective and there is need to adjust strategy. Research was undertaken with human test subjects to identify the factors that contribute to adaptive thinking. It was discovered that those most effective in settings that call for adaptive thinking tend to possess a superior capacity to quickly and effectively generate possible courses of action, as measured using the Category Generation test. Software developed for this research has been applied to develop capabilities enabling analysts to identify crucial factors that are predictive of outcomes in fore-on-force simulation exercises.

  5. Adaptive Optics for Large Telescopes

    SciTech Connect (OSTI)

    Olivier, S

    2008-06-27

    The use of adaptive optics was originally conceived by astronomers seeking to correct the blurring of images made with large telescopes due to the effects of atmospheric turbulence. The basic idea is to use a device, a wave front corrector, to adjust the phase of light passing through an optical system, based on some measurement of the spatial variation of the phase transverse to the light propagation direction, using a wave front sensor. Although the original concept was intended for application to astronomical imaging, the technique can be more generally applied. For instance, adaptive optics systems have been used for several decades to correct for aberrations in high-power laser systems. At Lawrence Livermore National Laboratory (LLNL), the world's largest laser system, the National Ignition Facility, uses adaptive optics to correct for aberrations in each of the 192 beams, all of which must be precisely focused on a millimeter scale target in order to perform nuclear physics experiments.

  6. Plutonium radiation surrogate

    DOE Patents [OSTI]

    Frank, Michael I. (Dublin, CA)

    2010-02-02

    A self-contained source of gamma-ray and neutron radiation suitable for use as a radiation surrogate for weapons-grade plutonium is described. The source generates a radiation spectrum similar to that of weapons-grade plutonium at 5% energy resolution between 59 and 2614 keV, but contains no special nuclear material and emits little .alpha.-particle radiation. The weapons-grade plutonium radiation surrogate also emits neutrons having fluxes commensurate with the gamma-radiation intensities employed.

  7. TH-A-BRD-01: Radiation Biology for Radiation Therapy Physicists

    SciTech Connect (OSTI)

    Orton, C; Borras, C; Carlson, D

    2014-06-15

    Mechanisms by which radiation kills cells and ways cell damage can be repaired will be reviewed. The radiobiological parameters of dose, fractionation, delivery time, dose rate, and LET will be discussed. The linear-quadratic model for cell survival for high and low dose rate treatments and the effect of repopulation will be presented and discussed. The rationale for various radiotherapy techniques such as conventional fractionation, hyperfractionation, hypofractionation, and low and high dose rate brachytherapy, including permanent implants, will be presented. The radiobiological principles underlying radiation protection guidelines and the different radiation dosimetry terms used in radiation biology and in radiation protection will be reviewed. Human data on radiation induced cancer, including increases in the risk of second cancers following radiation therapy, as well as data on radiation induced tissue reactions, such as cardiovascular effects, for follow up times up to 2040 years, published by ICRP, NCRP and BEIR Committees, will be examined. The latest risk estimates per unit dose will be presented. Their adoption in recent radiation protection standards and guidelines and their impact on patient and workers safety in radiotherapy will be discussed. Biologically-guided radiotherapy (BGRT) provides a systematic method to derive prescription doses that integrate patient-specific information about tumor and normal tissue biology. Treatment individualization based on patient-specific biology requires the identification of biological objective functions to facilitate the design and comparison of competing treatment modalities. Biological objectives provide a more direct approach to plan optimization instead of relying solely on dose-based surrogates and can incorporate factors that alter radiation response, such as DNA repair, tumor hypoxia, and relative biological effectiveness. We review concepts motivating biological objectives and provide examples of how they might be used to address clinically relevant problems. Underlying assumptions and limitations of existing models and their proper application will be discussed. This multidisciplinary educational session combines the fundamentals of radiobiology for radiation therapy and radiation protection with the practical application of biophysical models for treatment planning and evaluation. Learning Objectives: To understand fractionation in teletherapy and dose rate techniques in brachytherapy. To understand how the linear-quadratic models the effect of radiobiological parameters for radiotherapy. To understand the radiobiological basis of radiation protection standards applied to radiotherapy. To distinguish between stochastic effects and tissue reactions. To learn how to apply concepts of biological effective dose and RBE-weighted dose and to incorporate biological factors that alter radiation response. To discuss clinical strategies to increase therapeutic ratio, i.e., maximize local control while minimizing the risk of acute and late normal tissue effects.

  8. The effect of recombination radiation on the temperature and ionization state of partially ionized gas

    E-Print Network [OSTI]

    Rai?evi?, Milan; Schaye, Joop; Rahmati, Alireza

    2013-01-01

    A substantial fraction of all ionizing photons originate from radiative recombinations. However, in radiative transfer calculations this recombination radiation is often assumed to be absorbed 'on-the-spot' because for most methods the computational cost associated with the inclusion of gas elements as sources is prohibitive. We present a new, CPU and memory efficient implementation for the transport of ionizing recombination radiation in the TRAPHIC radiative transfer scheme. TRAPHIC solves the radiative transfer equation by tracing photon packets at the speed of light and in a photon-conserving manner in spatially adaptive smoothed particle hydrodynamics simulations. Our new implementation uses existing features of the TRAPHIC scheme to add recombination radiation at no additional cost in the limit in which the fraction of the simulation box filled with radiation approaches 1. We test the implementation by simulating an HII region in photoionization equilibrium and comparing to reference solutions presented...

  9. ENZO: AN ADAPTIVE MESH REFINEMENT CODE FOR ASTROPHYSICS

    SciTech Connect (OSTI)

    Bryan, Greg L.; Turk, Matthew J. [Columbia University, Department of Astronomy, New York, NY 10025 (United States); Norman, Michael L.; Bordner, James; Xu, Hao; Kritsuk, Alexei G. [CASS, University of California, San Diego, 9500 Gilman Drive La Jolla, CA 92093-0424 (United States); O'Shea, Brian W.; Smith, Britton [Department of Physics and Astronomy, Michigan State University, East Lansing, MI 48824 (United States); Abel, Tom; Wang, Peng; Skillman, Samuel W. [Kavli Institute for Particle Astrophysics and Cosmology, Stanford University, Menlo Park, CA 94025 (United States); Wise, John H. [Center for Relativistic Astrophysics, School of Physics, Georgia Institute of Technology, 837 State Street, Atlanta, GA (United States); Reynolds, Daniel R. [Department of Mathematics, Southern Methodist University, Box 750156, Dallas, TX 75205-0156 (United States); Collins, David C. [Department of Physics, Florida State University, Tallahassee, FL 32306 (United States); Harkness, Robert P. [NICS, Oak Ridge National Laboratory, 1 Bethel Valley Rd, Oak Ridge, TN 37831 (United States); Kim, Ji-hoon [Department of Astronomy and Astrophysics, University of California, 1156 High Street, Santa Cruz, CA 95064 (United States); Kuhlen, Michael [Theoretical Astrophysics Center, University of California Berkeley, Hearst Field Annex, Berkeley, CA 94720 (United States); Goldbaum, Nathan [Institute for Astronomy, University of Edinburgh, Edinburgh EH9 3HJ (United Kingdom); Hummels, Cameron [Department of Astronomy/Steward Observatory, University of Arizona, 933N. Cherry Ave., Tucson, AZ 85721 (United States); Tasker, Elizabeth [Physics Department, Faculty of Science, Hokkaido University, Kita-10 Nishi 8, Kita-ku, Sapporo 060-0810 (Japan); Collaboration: Enzo Collaboration; and others

    2014-04-01

    This paper describes the open-source code Enzo, which uses block-structured adaptive mesh refinement to provide high spatial and temporal resolution for modeling astrophysical fluid flows. The code is Cartesian, can be run in one, two, and three dimensions, and supports a wide variety of physics including hydrodynamics, ideal and non-ideal magnetohydrodynamics, N-body dynamics (and, more broadly, self-gravity of fluids and particles), primordial gas chemistry, optically thin radiative cooling of primordial and metal-enriched plasmas (as well as some optically-thick cooling models), radiation transport, cosmological expansion, and models for star formation and feedback in a cosmological context. In addition to explaining the algorithms implemented, we present solutions for a wide range of test problems, demonstrate the code's parallel performance, and discuss the Enzo collaboration's code development methodology.

  10. Polymer Composites for Radiation Scintillation

    E-Print Network [OSTI]

    Chen, Qi

    2012-01-01

    Reference G. F. Knoll, Radiation detection and measurement,MI, 1985. G. F. Knoll, Radiation detection and measurement,applications in radiation detection. First, a brief review

  11. WI Radiation Protection

    Broader source: Energy.gov [DOE]

    This statute seeks to regulate radioactive materials, to encourage the constructive uses of radiation, and to prohibit and prevent exposure to radiation in amounts which are or may be detrimental...

  12. Maryland Radiation Act (Maryland)

    Broader source: Energy.gov [DOE]

    The policy of the state is to provide for the constructive use of radiation and control radiation emissions. This legislation authorizes the Department of the Environment to develop comprehensive...

  13. The versatile E. coli adaptive response protein AlkB mitigates toxicity and mutagenicity of etheno-, ethano-, and methyl-modified bases in vivo

    E-Print Network [OSTI]

    Frick, Lauren Elizabeth

    2007-01-01

    The Escherichia coli AlkB protein is an exceptionally versatile DNA repair enzyme. Its expression is induced upon exposure to alkylating agents as part of the Ada-mediated adaptive response. This member of the ac-ketoglu ...

  14. Radiation protection at CERN

    E-Print Network [OSTI]

    Forkel-Wirth, Doris; Silari, Marco; Streit-Bianchi, Marilena; Theis, Christian; Vincke, Heinz; Vincke, Helmut

    2013-01-01

    This paper gives a brief overview of the general principles of radiation protection legislation; explains radiological quantities and units, including some basic facts about radioactivity and the biological effects of radiation; and gives an overview of the classification of radiological areas at CERN, radiation fields at high-energy accelerators, and the radiation monitoring system used at CERN. A short section addresses the ALARA approach used at CERN.

  15. Adaptive wiener image restoration kernel

    DOE Patents [OSTI]

    Yuan, Ding (Henderson, NV)

    2007-06-05

    A method and device for restoration of electro-optical image data using an adaptive Wiener filter begins with constructing imaging system Optical Transfer Function, and the Fourier Transformations of the noise and the image. A spatial representation of the imaged object is restored by spatial convolution of the image using a Wiener restoration kernel.

  16. diploma thesis Adaptive Building Intelligence

    E-Print Network [OSTI]

    Rutishauser, Ueli

    diploma thesis Adaptive Building Intelligence A multi-Agent approach Ueli Rutishauser Alain Sch intelligent. A building is perceived as be- ing intelligent if it is able to learn from experience. We is connected to the sensors and effectors via a dedicated fieldbus network (LonWorks). Based on this data

  17. Adaptive protection algorithm and system

    DOE Patents [OSTI]

    Hedrick, Paul (Pittsburgh, PA) [Pittsburgh, PA; Toms, Helen L. (Irwin, PA) [Irwin, PA; Miller, Roger M. (Mars, PA) [Mars, PA

    2009-04-28

    An adaptive protection algorithm and system for protecting electrical distribution systems traces the flow of power through a distribution system, assigns a value (or rank) to each circuit breaker in the system and then determines the appropriate trip set points based on the assigned rank.

  18. Viewing Conditions and Chromatic Adaptation

    E-Print Network [OSTI]

    Majumder, Aditi

    Linear nonlinear #12;2 Viewing field Self-luminous displays CRT, LCD Reflective media Painting Viewing: Adapting stimulus Subscript E: Equal energy illumination #12;13 Fairchild's model (1991) Inter channel brightness #12;6 11 Definition of Color Appearance Model so much description of color such as: wavelength

  19. THE VEX RADIATION MODULE: 2D RADIATION TRANSPORT WITH MIMETIC...

    Office of Scientific and Technical Information (OSTI)

    THE VEX RADIATION MODULE: 2D RADIATION TRANSPORT WITH MIMETIC DIFFUSION FOR EXAFLAG Citation Details In-Document Search Title: THE VEX RADIATION MODULE: 2D RADIATION TRANSPORT WITH...

  20. RADIONUCLIDE RADIATION PROTECTION

    E-Print Network [OSTI]

    Zakhor, Avideh

    RADIONUCLIDE AND RADIATION PROTECTION DATA HANDBOOK 2002 D. Delacroix* J. P. Guerre** P. Leblanc'Energie Atomique, CEA/Saclay, France ISBN 1 870965 87 6 RADIATION PROTECTION DOSIMETRY Vol. 98 No 1, 2002 Published by Nuclear Technology Publishing #12;RADIONUCLIDE AND RADIATION PROTECTION DATA HANDBOOK 2nd Edition (2002

  1. Harvesting nanoscale thermal radiation using pyroelectric materials

    E-Print Network [OSTI]

    Fang, Jin; Frederich, Hugo; Pilon, Laurent

    2010-01-01

    eld radiative heat transfer dominates radiation transferstudy Far field radiation Heat transfer coefficient, h r (W/nanoscale radiation to enhance radiative heat transfer. The

  2. Self-similar radiation from numerical Rosenau-Hyman compactons

    SciTech Connect (OSTI)

    Rus, Francisco Villatoro, Francisco R.

    2007-11-10

    The numerical simulation of compactons, solitary waves with compact support, is characterized by the presence of spurious phenomena, as numerically induced radiation, which is illustrated here using four numerical methods applied to the Rosenau-Hyman K(p, p) equation. Both forward and backward radiations are emitted from the compacton presenting a self-similar shape which has been illustrated graphically by the proper scaling. A grid refinement study shows that the amplitude of the radiations decreases as the grid size does, confirming its numerical origin. The front velocity and the amplitude of both radiations have been studied as a function of both the compacton and the numerical parameters. The amplitude of the radiations decreases exponentially in time, being characterized by a nearly constant scaling exponent. An ansatz for both the backward and forward radiations corresponding to a self-similar function characterized by the scaling exponent is suggested by the present numerical results.

  3. 2014 DOE Climate Change Adaptation Plan | Department of Energy

    Office of Environmental Management (EM)

    Climate Change Adaptation Plan 2014 DOE Climate Change Adaptation Plan Document presents the U.S. Department of Energy (DOE) 2014 plan for adapting to climate change....

  4. Radiation Effects in Nuclear Waste Materials

    SciTech Connect (OSTI)

    Weber, William J.; Corrales, L. Rene; Ness, Nancy J.; Williford, Ralph E.; Heinisch, Howard L.; Thevuthasan, Suntharampillai; Icenhower, Jonathan P.; McGrail, B. Peter; Devanathan, Ramaswami; Van Ginhoven, Renee M.; Song, Jakyoung; Park, Byeongwon; Jiang, Weilin; Begg, Bruce D.; Birtcher, R. B.; Chen, X.; Conradson, Steven D.

    2000-10-02

    Radiation effects from the decay of radionuclides may impact the long-term performance and stability of nuclear waste forms and stabilized nuclear materials. In an effort to address these concerns, the objective of this project was the development of fundamental understanding of radiation effects in glasses and ceramics, particularly on solid-state radiation effects and their influence on aqueous dissolution kinetics. This study has employed experimental, theoretical and computer simulation methods to obtain new results and insights into radiation damage processes and to initiate the development of predictive models. Consequently, the research that has been performed under this project has significant implications for the High-Level Waste and Nuclear Materials focus areas within the current DOE/EM mission. In the High-Level Waste (HLW) focus area, the results of this research could lead to improvements in the understanding of radiation-induced degradation mechanisms and their effects on dissolution kinetics, as well as development of predictive models for waste form performance. In the Nuclear Materials focus area, the results of this research could lead to improvements in the understanding of radiation effects on the chemical and structural properties of materials for the stabilization and long-term storage of plutonium, highly-enriched uranium, and other actinides. Ultimately, this research could result in improved glass and ceramic materials for the stabilization and immobilization of high-level tank waste, plutonium residues and scraps, surplus weapons plutonium, highly-enriched uranium, other actinides, and other radioactive materials.

  5. Multi-model adaptive spatial hypertext

    E-Print Network [OSTI]

    Francisco-Revilla, Luis

    2005-02-17

    Information delivery on the Web often relies on general purpose Web pages that require the reader to adapt to them. This limitation is addressed by approaches such as spatial hypermedia and adaptive hypermedia. Spatial hypermedia augments...

  6. CLIMATE VULNERABILITY AND ADAPTATION STUDY FOR

    E-Print Network [OSTI]

    CLIMATE VULNERABILITY AND ADAPTATION STUDY FOR CALIFORNIA Legal Analysis of Barriers's California Climate Change Center JULY 2012 CEC5002012019 Prepared for: California Energy Commission to that framework that would facilitate adaptation to climate change. Since such changes may be difficult

  7. Adaptive control of Unmanned Aerial Systems

    E-Print Network [OSTI]

    Dydek, Zachary Thompson

    2010-01-01

    Adaptive control is considered to be one of the key enabling technologies for future high-performance, safety-critical systems such as air-breathing hypersonic vehicles. Adaptive flight control systems offer improved ...

  8. Development of a Standardized Method for Contouring the Lumbosacral Plexus: A Preliminary Dosimetric Analysis of this Organ at Risk Among 15 Patients Treated With Intensity-Modulated Radiotherapy for Lower Gastrointestinal Cancers and the Incidence of Radiation-Induced Lumbosacral Plexopathy

    SciTech Connect (OSTI)

    Yi, Sun K., E-mail: sun.yi@ucdmc.ucdavis.edu [Department of Radiation Oncology, University of California, Davis Cancer Center, Sacramento, CA (United States); Mak, Walter [Department of Radiology, University of California, Davis Medical Center, Sacramento, CA (United States)] [Department of Radiology, University of California, Davis Medical Center, Sacramento, CA (United States); Yang, Claus C.; Liu Tianxiao [Department of Radiation Oncology, University of Mississippi Medical Center, Jackson, MS (United States)] [Department of Radiation Oncology, University of Mississippi Medical Center, Jackson, MS (United States); Cui Jing; Chen, Allen M.; Purdy, James A.; Monjazeb, Arta M. [Department of Radiation Oncology, University of California, Davis Cancer Center, Sacramento, CA (United States)] [Department of Radiation Oncology, University of California, Davis Cancer Center, Sacramento, CA (United States); Do, Ly [Cancer Care Institute, San Jose, CA (United States)] [Cancer Care Institute, San Jose, CA (United States)

    2012-10-01

    Purpose: To generate a reproducible step-wise guideline for the delineation of the lumbosacral plexus (LSP) on axial computed tomography (CT) planning images and to provide a preliminary dosimetric analysis on 15 representative patients with rectal or anal cancers treated with an intensity-modulated radiotherapy (IMRT) technique. Methods and Materials: A standardized method for contouring the LSP on axial CT images was devised. The LSP was referenced to identifiable anatomic structures from the L4-5 interspace to the level of the sciatic nerve. It was then contoured retrospectively on 15 patients treated with IMRT for rectal or anal cancer. No dose limitations were placed on this organ at risk during initial treatment planning. Dosimetric parameters were evaluated. The incidence of radiation-induced lumbosacral plexopathy (RILSP) was calculated. Results: Total prescribed dose to 95% of the planned target volume ranged from 50.4 to 59.4 Gy (median 54 Gy). The mean ({+-}standard deviation [SD]) LSP volume for the 15 patients was 100 {+-} 22 cm{sup 3} (range, 71-138 cm{sup 3}). The mean maximal dose to the LSP was 52.6 {+-} 3.9 Gy (range, 44.5-58.6 Gy). The mean irradiated volumes of the LSP were V40Gy = 58% {+-} 19%, V50Gy = 22% {+-} 23%, and V55Gy = 0.5% {+-} 0.9%. One patient (7%) was found to have developed RILSP at 13 months after treatment. Conclusions: The true incidence of RILSP in the literature is likely underreported and is not a toxicity commonly assessed by radiation oncologists. In our analysis the LSP commonly received doses approaching the prescribed target dose, and 1 patient developed RILSP. Identification of the LSP during IMRT planning may reduce RILSP. We have provided a reproducible method for delineation of the LSP on CT images and a preliminary dosimetric analysis for potential future dose constraints.

  9. Radiation Safety (Revised March 2010)

    E-Print Network [OSTI]

    of radiation and a unit of exposure 14 Biological effects of radiation and units of dose 19 ALARA policy

  10. Synchrotron Radiation in Polymer Science

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

    Synchrotron Radiation in Polymer Science Synchrotron Radiation in Polymer Science March 30-April 2, 2012; San Francisco...

  11. TERSat: Trapped Energetic Radiation Satellite

    E-Print Network [OSTI]

    Clements, Emily B.

    2012-01-01

    Radiation damage caused by interactions with high-energy particles in the Van Allen Radiation Belts is a leading

  12. Polymer Composites for Radiation Scintillation

    E-Print Network [OSTI]

    Chen, Qi

    2012-01-01

    Principles of radiation interaction in matter and detection,Principles of radiation interaction in matter and detection,

  13. RADIATION CHEMISTRY 2010 GORDON RESEARCH CONFERENCE JULY 18-23

    SciTech Connect (OSTI)

    Thomas Orlando

    2010-07-23

    The 2010 Gordon Conference on Radiation Chemistry will present cutting edge research regarding the study of radiation-induced chemical transformations. Radiation Chemistry or 'high energy' chemistry is primarily initiated by ionizing radiation: i.e. photons or particles with energy sufficient to create conduction band electrons and 'holes', excitons, ionic and neutral free radicals, highly excited states, and solvated electrons. These transients often interact or 'react' to form products vastly different than those produced under thermal equilibrium conditions. The non-equilibrium, non-thermal conditions driving radiation chemistry exist in plasmas, star-forming regions, the outer solar system, nuclear reactors, nuclear waste repositories, radiation-based medical/clinical treatment centers and in radiation/materials processing facilities. The 2010 conference has a strong interdisciplinary flavor with focus areas spanning (1) the fundamental physics and chemistry involved in ultrafast (atto/femtosecond) energy deposition events, (2) radiation-induced processes in biology (particularly spatially resolved studies), (3) radiation-induced modification of materials at the nanoscale and cosmic ray/x-ray mediated processes in planetary science/astrochemistry. While the conference concentrates on fundamental science, topical applied areas covered will also include nuclear power, materials/polymer processing, and clinical/radiation treatment in medicine. The Conference will bring together investigators at the forefront of their field, and will provide opportunities for junior scientists and graduate students to present work in poster format or as contributors to the Young Investigator session. The program and format provides excellent avenues to promote cross-disciplinary collaborations.

  14. EXACT WAVEFRONT CORRECTION IN ADAPTIVE OPTICS.

    E-Print Network [OSTI]

    Rosier, Lionel - Institut de Mathématiques ?lie Cartan, Université Henri Poincaré

    EXACT WAVEFRONT CORRECTION IN ADAPTIVE OPTICS. Pierre Le Gall Lionel Rosier Institut Elie Cartan an adaptive optical system in which a deformable mirror is controlled to compensate for random wavefront c 2005 IFAC Keywords: Adaptive optics, exact wavefront correction, membrane mirror. 1. INTRODUCTION

  15. Interferometry following adaptive optics Erez N. Ribak

    E-Print Network [OSTI]

    Ribak, Erez

    Interferometry following adaptive optics Erez N. Ribak Department of Physics, Technion, Haifa 32000, Israel ABSTRACT Adaptive optics systems on single big telescopes correct many modes, allowing imaging, adaptive optics, big telescopes, shearing interferometry. 1. THE IMPROVEMENT OF THE WAVE FRONT Most big

  16. Radiation Damage in Polarized Ammonia Solids

    E-Print Network [OSTI]

    K. Slifer

    2007-11-28

    Solid NH3 and ND3 provide a highly polarizable, radiation resistant source of polarized protons and deuterons and have been used extensively in high luminosity experiments investigating the spin structure of the nucleon. Over the past twenty years, the UVA polarized target group has been instrumental in producing and polarizing much of the material used in these studies, and many practical considerations have been learned in this time. In this discussion, we analyze the polarization performance of the solid ammonia targets used during the recent JLab Eg4 run. Topics include the rate of polarization decay with accumulated charge, the annealing procedure for radiation damaged targets to recover polarization, and the radiation induced change in optimum microwave frequency used to polarize the sample. We also discuss the success we have had in implementing frequency modulation of the polarizing microwave frequency.

  17. Cosmological birefringence induced by neutrino current

    E-Print Network [OSTI]

    C. Q. Geng; S. H. Ho; J. N. Ng

    2007-11-29

    We review our recent work on the cosmological birefringence. We propose a new type of effective interactions in terms of the $CPT$-even dimension-six Chern-Simons-like term to generate the cosmological birefringence. We use the neutrino number asymmetry to induce a non-zero rotation polarization angle in the data of the cosmic microwave background radiation polarization.

  18. On adaptive non-linearity for color discrimination and chromatic adaptation

    E-Print Network [OSTI]

    Alleysson, David

    the physiology literature that the photoreceptors' response to light is non-linear and adaptive. However, we can corresponding color data. Adaptive non-linearity Photoreceptors are the light-sensitive elements of the humanOn adaptive non-linearity for color discrimination and chromatic adaptation David Alleysson

  19. 1/18/2002 1 SelfSelf--Adaptive Discovery MechanismsAdaptive Discovery Mechanisms

    E-Print Network [OSTI]

    Mills, Kevin

    1/18/2002 1 SelfSelf--Adaptive Discovery MechanismsAdaptive Discovery Mechanisms for Improved, simulate, and evaluate self-adaptive algorithms to improve performance of discovery protocols regarding software Project ObjectiveProject Objective Research, design, evaluate, and implement self-adaptive

  20. Surface Radiation from GOES: A Physical Approach; Preprint

    SciTech Connect (OSTI)

    Habte, A.; Sengupta, M.; Wilcox, S.

    2012-09-01

    Models to compute Global Horizontal Irradiance (GHI) and Direct Normal Irradiance (DNI) have been in development over the last 3 decades. These models can be classified as empirical or physical, based on the approach. Empirical models relate ground based observations with satellite measurements and use these relations to compute surface radiation. Physical models consider the radiation received from the earth at the satellite and create retrievals to estimate surface radiation. While empirical methods have been traditionally used for computing surface radiation for the solar energy industry the advent of faster computing has made operational physical models viable. The Global Solar Insolation Project (GSIP) is an operational physical model from NOAA that computes GHI using the visible and infrared channel measurements from the GOES satellites. GSIP uses a two-stage scheme that first retrieves cloud properties and uses those properties in a radiative transfer model to calculate surface radiation. NREL, University of Wisconsin and NOAA have recently collaborated to adapt GSIP to create a 4 km GHI and DNI product every 30 minutes. This paper presents an outline of the methodology and a comprehensive validation using high quality ground based solar data from the National Oceanic and Atmospheric Administration (NOAA) Surface Radiation (SURFRAD) (http://www.srrb.noaa.gov/surfrad/sitepage.html) and Integrated Surface Insolation Study (ISIS) http://www.srrb.noaa.gov/isis/isissites.html), the Solar Radiation Research Laboratory (SRRL) at National Renewable Energy Laboratory (NREL), and Sun Spot One (SS1) stations.

  1. Los Alamos Science: Number 23, 1995. Radiation protection and the human radiation experiments

    SciTech Connect (OSTI)

    Cooper, N.G.

    1995-12-31

    There are a variety of myths and misconceptions about the ionizing radiation that surrounds and penetrates us all. Dispel a few of these by taking a leisurely tour of radiation and its properties, of the natural and man-made sources of ionizing radiation, and of the way doses are calculated. By damaging DNA and inducing genetic mutations, ionizing radiation can potentially initiate a cell on the road to cancer. The authors review what is currently known about regulation of cellular reproduction, DNA damage and repair, cellular defense mechanisms, and the specific cancer-causing genes that are susceptible to ionizing radiation. A rapid survey of the data on radiation effects in humans shows that high radiation doses increase the risk of cancer, whereas the effects of low doses are very difficult to detect. The hypothetical risks at low doses, which are estimated from the atomic-bomb survivors, are compared to the low-dose data so that the reader can assess the present level of uncertainty. As part of the openness initiative, ten individuals who have worked with plutonium during various periods in the Laboratory`s history were asked to share their experiences including their accidental intakes. The history and prognosis of people who have had plutonium exposures is discussed by the Laboratory`s leading epidemiologist.

  2. Adaptation and Identity of Yolmo

    E-Print Network [OSTI]

    Pokharel, Binod

    2005-01-01

    of tourist and establishment of hotels. To cope with the increasing firewood demand the people have planted trees on the edge of the agricultural land and LNP introduced solar energy to reduce the rate of firewood consumption. Timber is used basically... the adaptive mechanism of the households. He contends that the number of children in a households influence the diversification of the household economy. In this regards Fricke writes: 96 Occasional Papers The household labour force is largely determined...

  3. Ion-induced nuclear radiotherapy

    DOE Patents [OSTI]

    Horn, Kevin M. (Albuquerque, NM); Doyle, Barney L. (Albuquerque, NM)

    1996-01-01

    Ion-induced Nuclear Radiotherapy (INRT) is a technique for conducting radiosurgery and radiotherapy with a very high degree of control over the spatial extent of the irradiated volume and the delivered dose. Based upon the concept that low energy, ion induced atomic and nuclear reactions can be used to produce highly energetic reaction products at the site of a tumor, the INRT technique is implemented through the use of a conduit-needle or tube which conducts a low energy ion beam to a position above or within the intended treatment area. At the end of the conduit-needle or tube is a specially fabricated target which, only when struck by the ion beam, acts as a source of energetic radiation products. The inherent limitations in the energy, and therefore range, of the resulting reaction products limits the spatial extent of irradiation to a pre-defined volume about the point of reaction. Furthermore, since no damage is done to tissue outside this irradiated volume, the delivered dose may be made arbitrarily large. INRT may be used both as a point-source of radiation at the site of a small tumor, or as a topical bath of radiation to broad areas of diseased tissue.

  4. Ion-induced nuclear radiotherapy

    DOE Patents [OSTI]

    Horn, K.M.; Doyle, B.L.

    1996-08-20

    Ion-induced Nuclear Radiotherapy (INRT) is a technique for conducting radiosurgery and radiotherapy with a very high degree of control over the spatial extent of the irradiated volume and the delivered dose. Based upon the concept that low energy, ion induced atomic and nuclear reactions can be used to produce highly energetic reaction products at the site of a tumor, the INRT technique is implemented through the use of a conduit-needle or tube which conducts a low energy ion beam to a position above or within the intended treatment area. At the end of the conduit-needle or tube is a specially fabricated target which, only when struck by the ion beam, acts as a source of energetic radiation products. The inherent limitations in the energy, and therefore range, of the resulting reaction products limits the spatial extent of irradiation to a pre-defined volume about the point of reaction. Furthermore, since no damage is done to tissue outside this irradiated volume, the delivered dose may be made arbitrarily large. INRT may be used both as a point-source of radiation at the site of a small tumor, or as a topical bath of radiation to broad areas of diseased tissue. 25 figs.

  5. Adaptive Stabilization of Nonlinear Stochastic Systems

    SciTech Connect (OSTI)

    Florchinger, P. [URA CNRS No. 399, Departement de Mathematiques, UFR MIM, Universite de Metz, Ile du Saulcy, F 57045 Metz Cedex (France)

    1998-07-15

    The purpose of this paper is to study the problem of asymptotic stabilization in probability of nonlinear stochastic differential systems with unknown parameters. With this aim, we introduce the concept of an adaptive control Lyapunov function for stochastic systems and we use the stochastic version of Artstein's theorem to design an adaptive stabilizer. In this framework the problem of adaptive stabilization of a nonlinear stochastic system is reduced to the problem of asymptotic stabilization in probability of a modified system. The design of an adaptive control Lyapunov function is illustrated by the example of adaptively quadratically stabilizable in probability stochastic differential systems.

  6. Cellular transformation by radiation: induction, promotion, and inhibition

    SciTech Connect (OSTI)

    Borek, C.

    1981-01-01

    Radiation oncogenesis induced in utero in hamsters is expressed at a lower frequency than that induced in vitro. Quantitative studies carried out on hamster embryo cells indicate that neutrons are more effective in their carcinogenic potential than x-rays but also more toxic, that splitting the dose of x-rays at low doses leads to enhanced transformation, but that at high doses protracted radiation has a sparing effect. At all dose ranges survival was increased by protracting the radiation dose, thus suggesting that different repair processes must be involved for survival and transformation. In our qualitative studies, once cells are transformed by radiation, they exhibit a wide range of structural and functional phenotypic changes, some of which are membrane-associated and are expressed within days after induction. Our current studies on nutritional and hormonal influences on radiation transformation indicate the following: Pyrolysate products from broiled protein foods act in synergism with radiation to produce transformation, whereas vitamin A analogs are powerful, preventive agents. Retinoids inhibit both x-ray-induced transformation and its promotion by TPA; these modifications (enhancement by TPA, inhibition by retinoids) are not reflected in sister chromatid exchanges, but are reflected in the level of membrane associated enzymes Na/K ATPase. Whereas retinoids modify late events (expression, promotion), we find that thyroid hormone plays a crucial role in the early phases of radiation and chemically induced transformation. Our recent success in transforming human skin fibroblasts will enable quantitative and qualitative studies of radiation carcinogenesis in a system relevant to man.

  7. Title: Prompt Creation of New Radiation Belts Cluster: Cross-Theme Theory and Data Analysis/SECTP

    E-Print Network [OSTI]

    Lotko, William

    Title: Prompt Creation of New Radiation Belts Cluster: Cross-Theme Theory and Data Analysis/SECTP Contributor: William Lotko/Dartmouth College Radiation belt genesis via shock-induced magnetospheric compression The unexpected creation of new electron and proton radiation belts during the March 24, 1991

  8. Title: Prompt Creation of New Radiation Belts Cluster: Cross-Theme Theory and Data Analysis/SECTP

    E-Print Network [OSTI]

    Lotko, William

    Title: Prompt Creation of New Radiation Belts Cluster: Cross-Theme Theory and Data Analysis-pushing code for radiation belt particles in a global MHD simulation of the solar wind/SECTP Contributor: William Lotko/Dartmouth College Radiation belt genesis via shock-induced magnetospheric

  9. Center for Adaptive Optics* Santa Cruz,CA

    E-Print Network [OSTI]

    Grether, Gregory

    Center for Adaptive Optics* Santa Cruz,CA The Center for Adaptive Optics (CfAO) will concentrate on astronomical and vision science applications of adaptive optics and will reach out to other adaptive optics communities to share technologies. It will develop new instruments optimized for adaptive optics. Adaptive

  10. RHOBOT: Radiation hardened robotics

    SciTech Connect (OSTI)

    Bennett, P.C.; Posey, L.D.

    1997-10-01

    A survey of robotic applications in radioactive environments has been conducted, and analysis of robotic system components and their response to the varying types and strengths of radiation has been completed. Two specific robotic systems for accident recovery and nuclear fuel movement have been analyzed in detail for radiation hardness. Finally, a general design approach for radiation-hardened robotics systems has been developed and is presented. This report completes this project which was funded under the Laboratory Directed Research and Development program.

  11. Radiation Hazards Program (Minnesota)

    Broader source: Energy.gov [DOE]

    These regulations, promulgated by the Department of Health, set allowable radiation standards and mitigation practices, as well as procedures for the transportation of hazardous material.

  12. Atomic Radiation (Illinois)

    Broader source: Energy.gov [DOE]

    This article states permissible levels of radiation in unrestricted areas, environmental standards for uranium fuel cycle and information about notification of incidents.

  13. A new radiometer for earth radiation budget studies

    SciTech Connect (OSTI)

    Weber, P.G.

    1992-05-01

    A critical need for the US Global Change Research Program is to provide continuous, well-calibrated radiometric data for radiation balance studies. This paper describes a new, compact, relatively light-weight, adaptable radiometer which will provide both spectrally integrated measurements and data in selected spectral bands. The radiometer design is suitable for use on (small) satellites, aircraft, or Unmanned Aerospace Vehicles (UAVs). Some considerations for the implementation of this radiometer on a small satellite are given. 17 refs.

  14. A new radiometer for earth radiation budget studies

    SciTech Connect (OSTI)

    Weber, P.G.

    1992-01-01

    A critical need for the US Global Change Research Program is to provide continuous, well-calibrated radiometric data for radiation balance studies. This paper describes a new, compact, relatively light-weight, adaptable radiometer which will provide both spectrally integrated measurements and data in selected spectral bands. The radiometer design is suitable for use on (small) satellites, aircraft, or Unmanned Aerospace Vehicles (UAVs). Some considerations for the implementation of this radiometer on a small satellite are given. 17 refs.

  15. Adaptive capture of expert behavior

    SciTech Connect (OSTI)

    Jones, R.D.; Barrett, C.L.; Hand, U.; Gordon, R.C.

    1994-08-01

    The authors smoothed and captured a set of expert rules with adaptive networks. The motivation for doing this is discussed. (1) Smoothing leads to stabler control actions. (2) For some sets of rules, the evaluation of the rules can be sped up. This is important in large-scale simulations where many intelligent elements are present. (3) Variability of the intelligent elements can be achieved by adjusting the weights in an adaptive network. (4) After capture has occurred, the weights can be adjusted based on performance criteria. The authors thus have the capability of learning a new set of rules that lead to better performance. The set of rules the authors chose to capture were based on a set of threat determining rules for tank commanders. The approach in this paper: (1) They smoothed the rules. The rule set was converted into a simple set of arithmetic statements. Continuous, non-binary inputs, are now permitted. (2) An operational measure of capturability was developed. (3) They chose four candidate networks for the rule set capture: (a) multi-linear network, (b) adaptive partial least squares, (c) connectionist normalized local spline (CNLS) network, and (d) CNLS net with a PLS preprocessor. These networks were able to capture the rule set to within a few percent. For the simple tank rule set, the multi-linear network performed the best. When the rules were modified to include more nonlinear behavior, CNLS net performed better than the other three nets which made linear assumptions. (4) The networks were tested for robustness to input noise. Noise levels of plus or minus 10% had no real effect on the network performance. Noise levels in the plus or minus 30% range degraded performance by a factor of two. Some performance enhancement occurred when the networks were trained with noisy data. (5) The scaling of the evaluation time was calculated. (6) Human variation can be mimicked in all the networks by perturbing the weights.

  16. Efficient weakly-radiative wireless energy transfer: An EIT-like approach

    E-Print Network [OSTI]

    Hamam, Rafif E.

    Inspired by a quantum interference phenomenon known in the atomic physics community as electromagnetically induced transparency (EIT), we propose an efficient weakly radiative wireless energy transfer scheme between two ...

  17. Mechanical Properties and Radiation Tolerance of Ultrafine Grained and Nanocrystalline Metals

    E-Print Network [OSTI]

    Sun, Cheng

    2013-04-26

    loops. Here we provide experimental evidence that high angle grain boundaries can effectively remove radiation-induced defects. The equal channel angular pressing (ECAP) technique was used to produce ultrafine grained Fe-Cr-Ni alloy. Mechanical...

  18. Effects of High Dietary Iron and Gamma Radiation on Oxidative Stress and Bone

    E-Print Network [OSTI]

    Yuen, Evelyn P

    2013-04-19

    Astronauts in space flight missions are exposed to increased iron (Fe) stores and galactic cosmic radiation, both of which independently induce oxidative stress. Oxidative stress can result in protein, lipid, and DNA oxidation. Recent evidence has...

  19. Lack of Bystander Effects From High LET Radiation For Early Cytogenetic Endpoints.

    E-Print Network [OSTI]

    Groesser, Torsten

    2009-01-01

    99, 159-162 (2002). C. Mothersill, R. J. Seymour and C.B. Seymour, Bystander effects in repair-deficient cellC. Mothersill and C. Seymour, Radiation-induced bystander

  20. ON THE JITTER RADIATION

    SciTech Connect (OSTI)

    Kelner, S. R. [Max-Planck-Institut fuer Kernphysik, Saupfercheckweg 1, D-6917 Heidelberg (Germany); Aharonian, F. A. [Dublin Institute for Advanced Studies, 31 Fitzwilliam Place, Dublin 2 (Ireland); Khangulyan, D., E-mail: skelner@rambler.ru, E-mail: Felix.Aharonian@mpi-hd.mpg.de, E-mail: khangul@astro.isas.jaxa.jp [Institute of Space and Astronautical Science/JAXA, 3-1-1 Yoshinodai, Chuo-ku, Sagamihara, Kanagawa 252-5210 (Japan)

    2013-09-01

    In a small-scale turbulent medium, when the nonrelativistic Larmor radius R{sub L} = mc {sup 2}/eB exceeds the correlation length {lambda} of the magnetic field, the magnetic Bremsstrahlung radiation of charged relativistic particles unavoidably proceeds to the so-called jitter radiation regime. The cooling timescale of parent particles is identical to the synchrotron cooling time, thus this radiation regime can be produced with very high efficiency in different astrophysical sources characterized by high turbulence. The jitter radiation has distinct spectral features shifted toward high energies, compared to synchrotron radiation. This effect makes the jitter mechanism an attractive broad-band gamma-ray production channel, which, in highly magnetized and turbulent environments, can compete or even dominate over other high-energy radiation mechanisms. In this paper, we present a novel study of the spectral properties of the jitter radiation performed within the framework of perturbation theory. The derived general expression for the spectral power of radiation is presented in a compact and convenient form for numerical calculations.

  1. Radiative Flux Analysis

    SciTech Connect (OSTI)

    Long, Chuck

    2008-05-14

    The Radiative Flux Analysis is a technique for using surface broadband radiation measurements for detecting periods of clear (i.e. cloudless) skies, and using the detected clear-sky data to fit functions which are then used to produce continuous clear-sky estimates. The clear-sky estimates and measurements are then used in various ways to infer cloud macrophysical properties.

  2. Radiation-resistant microorganism

    DOE Patents [OSTI]

    Fliermans, Carl B.

    2010-06-15

    An isolated and purified bacterium is provided which was isolated from a high-level radioactive waste site of mixed waste. The isolate has the ability to degrade a wide variety of organic contaminants while demonstrating high tolerance to ionizing radiation. The organism is uniquely suited to bioremediation of a variety or organic contaminants while in the presence of ionizing radiation.

  3. Photochemistry Radiation and Photolysis

    E-Print Network [OSTI]

    Toohey, Darin W.

    energy is done (i.e. energy per unit time) #12;Sample Problem: A microwave oven puts out radiation at 50? How does a microwave oven heat food anyway? First note that 50 GHz is a frequency (Hz = s-1) E = hn, as a function of l Amount of solar radiation, as a function of

  4. Appendix G. Radiation Appendix G. Radiation

    E-Print Network [OSTI]

    Pennycook, Steve

    energy, is energy in the form of waves or particles moving through space. Visi- ble light, heat, radio in the form of electromagnetic waves. Examples include gamma rays, ultraviolet light, and radio waves waves, and alpha particles are examples of radiation. When people feel warmth from sunlight

  5. Hormetic Effect Induced by Alpha-Particle-Induced Stress Communicated In Vivo between Zebrafish Embryos

    E-Print Network [OSTI]

    Yu, Peter K.N.

    response (RAR) by communica- tion of radiation-induced bystander signals.5 RAR is a low-dose effect, which to a low-dose alpha-particle irradiation can release a stress signal into the water, which can-response relationships exhibiting a low-dose stimulation and a high-dose inhibition. The effects on the whole embryos

  6. AN ADAPTIVE FINITE ELEMENT METHOD FOR THE ...

    E-Print Network [OSTI]

    2015-06-30

    Scattering theory in periodic structures, which is crucial in application .... is used to design the adaptive finite element algorithm to choose elements for refine-.

  7. Training for Climate Adaptation in Conservation

    Office of Energy Efficiency and Renewable Energy (EERE)

    The Wildlife Conservation Society and the Northern Institute of Applied Climate Science are hosting this two-day training for climate adaptation.

  8. Assessing Climate Change Impacts, Vulnerability and Adaptation...

    Open Energy Info (EERE)

    Assessing Climate Change Impacts, Vulnerability and Adaptation: The Case of Pantabangan-Carranglan Watershed Jump to: navigation, search Name Assessing Climate Change Impacts,...

  9. Mainstreaming Climate Change Adaptation into Development Planning...

    Open Energy Info (EERE)

    Mainstreaming Climate Change Adaptation into Development Planning: A Guide for Practitioners Jump to: navigation, search Tool Summary LAUNCH TOOL Name: Mainstreaming Climate Change...

  10. Protein Structure Suggests Role as Molecular Adapter

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

    Role as Molecular Adapter Print To split and copy DNA during replication, all cellular organisms use a multicomponent molecular machine known as the replisome. An essential...

  11. RADIATION DAMAGE OF GERMANIUM DETECTORS

    E-Print Network [OSTI]

    Pehl, Richard H.

    2011-01-01

    occurring within the detector, radiation may also change theLBL-7967 RADIATION DAMAGE OF GERMANIUM DETECTORS Richard H.LBL-7967 RADIATION DAMAGE OF GERMANIUM DETECTORS* Richard H.

  12. Radiation physics, biophysics, and radiation biology. Progress report, December 1, 1991--November 30, 1992

    SciTech Connect (OSTI)

    Hall, E.J.

    1992-05-01

    The following research programs from the Center for Radiological Research of Columbia University are described: Design and development of a new wall-less ultra miniature proportional counter for nanodosimetry; some recent measurements of ionization distributions for heavy ions at nanometer site sizes with a wall-less proportional counter; a calculation of exciton energies in periodic systems with helical symmetry: application to a hydrogen fluoride chain; electron energy-loss function in polynucleotide and the question of plasmon excitation; a non-parametric, microdosimetric-based approach to the evaluation of the biological effects of low doses of ionizing radiation; high-LET radiation risk assessment at medium doses; high-LET radiobiological effects: increased lesion severity or increased lesion proximity; photoneutrons generated by high energy medical linacs; the biological effectiveness of neutrons; implications for radiation protection; molecular characterization of oncogenes induced by neutrons; and the inverse dose-rate effect for oncogenic transformation by charged particles is LET dependent.

  13. A Geometric Characterization of the Power of Finite Adaptability in Multistage Stochastic and Adaptive Optimization

    E-Print Network [OSTI]

    Bertsimas, Dimitris J.

    In this paper, we show a significant role that geometric properties of uncertainty sets, such as symmetry, play in determining the power of robust and finitely adaptable solutions in multistage stochastic and adaptive ...

  14. Radiation Leukemogenesis at Low Dose Rates

    SciTech Connect (OSTI)

    Weil, Michael; Ullrich, Robert

    2013-09-25

    The major goals of this program were to study the efficacy of low dose rate radiation exposures for the induction of acute myeloid leukemia (AML) and to characterize the leukemias that are caused by radiation exposures at low dose rate. An irradiator facility was designed and constructed that allows large numbers of mice to be irradiated at low dose rates for protracted periods (up to their life span). To the best of our knowledge this facility is unique in the US and it was subsequently used to study radioprotectors being developed for radiological defense (PLoS One. 7(3), e33044, 2012) and is currently being used to study the role of genetic background in susceptibility to radiation-induced lung cancer. One result of the irradiation was expected; low dose rate exposures are ineffective in inducing AML. However, another result was completely unexpected; the irradiated mice had a very high incidence of hepatocellular carcinoma (HCC), approximately 50%. It was unexpected because acute exposures are ineffective in increasing HCC incidence above background. This is a potential important finding for setting exposure limits because it supports the concept of an 'inverse dose rate effect' for some tumor types. That is, for the development of some tumor types low dose rate exposures carry greater risks than acute exposures.

  15. Measuring the Radiation Reliability of SRAM Structures in GPUs Designed for HPC

    E-Print Network [OSTI]

    Keckler, Stephen W.

    results from an extensive radiation test campaign that was performed at LANSCE in Los Alamos, New Mexico GPU corrupted by neutrons. Caches and internal register files, due to their large size, high density. As reported in [4] and [5], most of the radiation-induced failures in GPUs are caused by corruption of memory

  16. Radiation Damage/Materials Modification

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

    ion irradiation is an important tool for studying radiation damage effects Materials in a nuclear reactor are exposed to extreme temperature and radiation conditions that degrade...

  17. Florida Radiation Protection Act (Florida)

    Broader source: Energy.gov [DOE]

    The Department of Public Health is responsible for administering a statewide radiation protection program. The program is designed to permit development and utilization of sources of radiation for...

  18. Impact of the Geo-synchronous Orbit Radiation Environment on the Design of Astronomical Observatories

    E-Print Network [OSTI]

    Kruk, Jeffrey W; Armani, Nerses; Stauffer, Craig; Hirata, Christopher M

    2015-01-01

    Geo-Synchronous orbits are appealing for Solar or astrophysical observatories because they permit continuous data downlink at high rates. The radiation environment in these orbits presents unique challenges, however. This paper describes the characteristics of the radiation environment in Geo-Synchronous orbit and the implications for instrument design. Radiation-induced background event rates are given for some simplified shielding models, and for a detailed model of the proposed Wide-Field InfraRed Survey Telescope observatory.

  19. Stimulated Emission of Radiation in a Nuclear Fusion Reaction

    E-Print Network [OSTI]

    Michael Duren

    1999-04-06

    This letter claims that process of stimulated emission of radiation can be used to induce a fusion reaction in a HD molecule to produce Helium-3. An experimental set-up for this reaction is presented. It is proposed to study the technical potential of this reaction as an energy amplifier.

  20. Radiation Safety System

    SciTech Connect (OSTI)

    Vylet, Vaclav; Liu, James C.; Walker, Lawrence S.; /Los Alamos

    2012-04-04

    The goal of this work is to provide an overview of a Radiation safety system (RSS) designed for protection from prompt radiation hazard at accelerator facilities. RSS design parameters, functional requirements and constraints are derived from hazard analysis and risk assessment undertaken in the design phase of the facility. The two main subsystems of a RSS are access control system (ACS) and radiation control system (RCS). In this text, a common approach to risk assessment, typical components of ACS and RCS, desirable features and general design principles applied to RSS are described.

  1. Composition for radiation shielding

    DOE Patents [OSTI]

    Kronberg, James W. (Aiken, SC)

    1994-01-01

    A composition for use as a radiation shield. The shield has a depleted urum core for absorbing gamma rays and a bismuth coating for preventing chemical corrosion and absorbing gamma rays. Alternatively, a sheet of gadolinium may be positioned between the uranium core and the bismuth coating for absorbing neutrons. The composition is preferably in the form of a container for storing materials that emit radiation such as gamma rays and neutrons. The container is preferably formed by casting bismuth around a pre-formed uranium container having a gadolinium sheeting, and allowing the bismuth to cool. The resulting container is a structurally sound, corrosion-resistant, radiation-absorbing container.

  2. Miniaturized radiation chirper

    DOE Patents [OSTI]

    Umbarger, C. John (Los Alamos, NM); Wolf, Michael A. (Los Alamos, NM)

    1980-01-01

    The disclosure relates to a miniaturized radiation chirper for use with a small battery supplying on the order of 5 volts. A poor quality CdTe crystal which is not necessarily suitable for high resolution gamma ray spectroscopy is incorporated with appropriate electronics so that the chirper emits an audible noise at a rate that is proportional to radiation exposure level. The chirper is intended to serve as a personnel radiation warning device that utilizes new and novel electronics with a novel detector, a CdTe crystal. The resultant device is much smaller and has much longer battery life than existing chirpers.

  3. AdaptUbiFlow: Selection and Adaptation in Workflows for Ubiquitous Computing Frederico Lopes, Thiago Pereira,

    E-Print Network [OSTI]

    Ferreira, Paulo

    AdaptUbiFlow: Selection and Adaptation in Workflows for Ubiquitous Computing Frederico Lopes will be chosen. AdaptUbiFlow evaluation showed encouraging results Keywords--Ubiquitous computing, platform The current trend in ubiquitous computing is the emergence of complex context-aware applications in which

  4. Downhole tool adapted for telemetry

    DOE Patents [OSTI]

    Hall, David R. (Provo, UT); Fox, Joe (Provo, UT)

    2010-12-14

    A cycleable downhole tool such as a Jar, a hydraulic hammer, and a shock absorber adapted for telemetry. This invention applies to other tools where the active components of the tool are displaced when the tool is rotationally or translationally cycled. The invention consists of inductive or contact transmission rings that are connected by an extensible conductor. The extensible conductor permits the transmission of the signal before, after, and during the cycling of the tool. The signal may be continuous or intermittent during cycling. The invention also applies to downhole tools that do not cycle, but in operation are under such stress that an extensible conductor is beneficial. The extensible conductor may also consist of an extensible portion and a fixed portion. The extensible conductor also features clamps that maintain the conductor under stresses greater than that seen by the tool, and seals that are capable of protecting against downhole pressure and contamination.

  5. Subwavelength films for standoff radiation dosimetry

    SciTech Connect (OSTI)

    Alvine, Kyle J.; Bernacki, Bruce E.; Bennett, Wendy D.; Schemer-Kohrn, Alan L.; Suter, Jonathan D.

    2015-05-22

    We present optical subwavelength nanostructure architecture suitable for standoff radiation dosimetry with remote optical readout in the visible or infrared spectral regions. To achieve this, films of subwavelength structures are fabricated over several square inches via the creation of a 2D non-close packed (NCP) array template of radiation-sensitive polymeric nanoparticles, followed by magnetron sputtering of a metallic coating to form a 2D array of separated hemispherical nanoscale metallic shells. The nanoshells are highly reflective at resonance in the visible or infrared depending on design. These structures and their behavior are based on the open ring resonator (ORR) architecture and have their analog in resonant inductive-capacitive (LC) circuits, which display a resonance wavelength that is inversely proportional to the square root of the product of the inductance and capacitance. Therefore, any modification of the nanostructure material properties due to radiation alters the inductive or capacitive behavior of the subwavelength features, which in turn changes their optical properties resulting in a shift in the optical resonance. This shift in resonance may be remotely interrogated actively using either laser illumination or passively by hyperspectral or multispectral sensing with broadband illumination. These structures may be designed to be either anisotropic or isotropic, which can also offer polarization-sensitive interrogation. We present experimental measurements of a radiation induced shift in the optical resonance of a subwavelength film after exposure to an absorbed dose of gamma radiation from 2 Mrad up to 62 Mrad demonstrating the effect. Interestingly the resonance shift is non-monotonic for this material system and possible radiation damage mechanisms to the nanoparticles are discussed.

  6. Method and apparatus for measuring spatial uniformity of radiation

    DOE Patents [OSTI]

    Field, Halden (Boulder, CO)

    2002-01-01

    A method and apparatus for measuring the spatial uniformity of the intensity of a radiation beam from a radiation source based on a single sampling time and/or a single pulse of radiation. The measuring apparatus includes a plurality of radiation detectors positioned on planar mounting plate to form a radiation receiving area that has a shape and size approximating the size and shape of the cross section of the radiation beam. The detectors concurrently receive portions of the radiation beam and transmit electrical signals representative of the intensity of impinging radiation to a signal processor circuit connected to each of the detectors and adapted to concurrently receive the electrical signals from the detectors and process with a central processing unit (CPU) the signals to determine intensities of the radiation impinging at each detector location. The CPU displays the determined intensities and relative intensity values corresponding to each detector location to an operator of the measuring apparatus on an included data display device. Concurrent sampling of each detector is achieved by connecting to each detector a sample and hold circuit that is configured to track the signal and store it upon receipt of a "capture" signal. A switching device then selectively retrieves the signals and transmits the signals to the CPU through a single analog to digital (A/D) converter. The "capture" signal. is then removed from the sample-and-hold circuits. Alternatively, concurrent sampling is achieved by providing an A/D converter for each detector, each of which transmits a corresponding digital signal to the CPU. The sampling or reading of the detector signals can be controlled by the CPU or level-detection and timing circuit.

  7. Optimized multifrequency light collection by adaptive self-ordering of scatterers in optical resonators

    E-Print Network [OSTI]

    Torggler, Valentin

    2014-01-01

    Mobile light scatterers in a high-Q optical cavity transversely illuminated by laser light close to a cavity resonance form ordered patterns, which maximize light scattering into the cavity and induce optical self-trapping. We show that a generalized form of such crystallization dynamics appears in multicolored pump fields with several cavity modes. Here the particles arrange in spatial patterns maximizing total light collection into the resonator. For changing input frequencies and strengths the particles dynamically adapt to the current illumination. Interestingly the system keeps some memory on past configurations, so that a later renewed application of the same pattern exhibits faster adaptation towards optimal collective scattering. In a noisy environment particles explore larger regions of configuration space spending most of the time close to optimum scattering configurations. This adaptive self-ordering dynamics should be implementable in a wide range of systems ranging from cold atoms in multimode ca...

  8. Enabling Informed Adaptation of Reformed Instructional Materials

    E-Print Network [OSTI]

    Elby, Andy

    Enabling Informed Adaptation of Reformed Instructional Materials Rachel E. Scherr and Andrew Elby 20742 USA Abstract. Instructors inevitably need to adapt even the best reform materials to suit instructors, and video clips of students working on the materials. Our materials thus facilitate their own

  9. Adaptive Communication Agent for Group Communication activities

    E-Print Network [OSTI]

    Paris-Sud XI, Universit de

    , limited energy resources), system execute adaptive mechanisms by monitoring the data flow. Also, the actor-wide collaborative environment, managing the adaptive communication is a challenging task. It implies the monitoring and executed without manual intervention. This research is applied to a Crisis Management System (CMS) within

  10. RESEARCH ARTICLE Adaptive Resistance in Bacteria Requires

    E-Print Network [OSTI]

    Cluzel, Philippe

    RESEARCH ARTICLE Adaptive Resistance in Bacteria Requires Epigenetic Inheritance, Genetic Noise Resistance in Bacteria Requires Epigenetic Inheritance, Genetic Noise, and Cost of Efflux Pumps. PLoS ONE 10, Cambridge, Massachusetts, United States of America * max@fis.unam.mx Abstract Adaptive resistance emerges

  11. CLIMATE CHANGE ADAPTATIONS FOR LOCAL WATER MANAGEMENT

    E-Print Network [OSTI]

    CLIMATE CHANGE ADAPTATIONS FOR LOCAL WATER MANAGEMENT IN THE SAN FRANCISCO BAY AREA water managers can adapt by changing water supply portfolios and operations. An engineering economic A White Paper from the California Energy Commission's California Climate Change Center JULY 2012 CEC

  12. ADAPTIVE GRIDS IN WEATHER AND CLIMATE MODELING

    E-Print Network [OSTI]

    Jablonowski, Christiane

    ADAPTIVE GRIDS IN WEATHER AND CLIMATE MODELING by Christiane Jablonowski A dissertation submitted adaptive grid library that he wrote for his Ph.D. thesis in the Electrical Engineering and Computer Science as a postdoctoral researcher. In addition, thanks to Detlev Majewski from the German Weather Service DWD

  13. Adaptive User Profiles in Pervasive Advertising Environments

    E-Print Network [OSTI]

    Adaptive User Profiles in Pervasive Advertising Environments Florian Alt1 , Moritz Balz2 , Stefanie advertising environments try to provide more effi- cient ads by targeting costumers based on their interests. We implemented an advertising platform to simulate an advertising environment and present adaptive

  14. Adaptive Representation of Specular Light Flux

    E-Print Network [OSTI]

    Montral, Universit de

    Adaptive Representation of Specular Light Flux Normand Bri`ere Pierre Poulin Departement d in all but the simplest con- figurations. To capture their appearance, we present an adaptive approach based upon light beams. The coher- ence between light rays forming a light beam greatly re- duces

  15. A fuzzy-tuned adaptive Kalman filter

    E-Print Network [OSTI]

    Painter, John H.; Young Hwan Lho

    1993-12-01

    In this paper, fuzzy processing is applied to the adaptive Kalman filter. The filter gain coefficients are adapted over a 50 dB range of unknown signal/noise dynamics, using fuzzy membership functions. Specific simulation results are shown for a...

  16. Formulating and Implementing Profiling over Adaptive Ranges

    E-Print Network [OSTI]

    Sherwood, Tim

    be implemented for range-adaptive profiling. RAP can be used on various profiles, such as PCs, load values may easily be lost in a sea of data. We present range-adaptive profiling (RAP) as a new and general value locality. We propose two methods of implementation of RAP, one in software and the other

  17. DIRECT ADAPTIVE CONTROL OF RESIN TRANSFER MOLDING

    E-Print Network [OSTI]

    Mamishev, Alexander

    of defects, control of mold filling is needed. In this paper, direct adaptive control strategy is presented is a crucial stage in RTM. Defect-free parts cannot be obtained without successful consistent mold fillingDIRECT ADAPTIVE CONTROL OF RESIN TRANSFER MOLDING B. Minaie1,* , W. Li, J. Gou1 , Y. Chen2 , A

  18. Adaptive Web Sites: Automatically Synthesizing Web Pages

    E-Print Network [OSTI]

    Etzioni, Oren

    Adaptive Web Sites: Automatically Synthesizing Web Pages Mike Perkowitz Oren Etzioni Department interfaces Abstract The creation of a complex web site is a thorny problem in user interface design. In IJCAI '97, we challenged the AI community to address this problem by creating adaptive web sites: sites

  19. Portal radiation monitor

    DOE Patents [OSTI]

    Kruse, L.W.

    1982-03-23

    A portal radiation monitor combines .1% FAR with high sensitivity to special nuclear material. The monitor utilizes pulse shape discrimination, dynamic compression of the photomultiplier output and scintillators sized to maintain efficiency over the entire portal area.

  20. Portal radiation monitor

    DOE Patents [OSTI]

    Kruse, Lyle W. (Albuquerque, NM)

    1985-01-01

    A portal radiation monitor combines 0.1% FAR with high sensitivity to special nuclear material. The monitor utilizes pulse shape discrimination, dynamic compression of the photomultiplier output and scintillators sized to maintain efficiency over the entire portal area.

  1. Amorphous silicon radiation detectors

    DOE Patents [OSTI]

    Street, Robert A. (Palo Alto, CA); Perez-Mendez, Victor (Berkeley, CA); Kaplan, Selig N. (El Cerrito, CA)

    1992-01-01

    Hydrogenated amorphous silicon radiation detector devices having enhanced signal are disclosed. Specifically provided are transversely oriented electrode layers and layered detector configurations of amorphous silicon, the structure of which allow high electric fields upon application of a bias thereby beneficially resulting in a reduction in noise from contact injection and an increase in signal including avalanche multiplication and gain of the signal produced by incoming high energy radiation. These enhanced radiation sensitive devices can be used as measuring and detection means for visible light, low energy photons and high energy ionizing particles such as electrons, x-rays, alpha particles, beta particles and gamma radiation. Particular utility of the device is disclosed for precision powder crystallography and biological identification.

  2. Amorphous silicon radiation detectors

    DOE Patents [OSTI]

    Street, R.A.; Perez-Mendez, V.; Kaplan, S.N.

    1992-11-17

    Hydrogenated amorphous silicon radiation detector devices having enhanced signal are disclosed. Specifically provided are transversely oriented electrode layers and layered detector configurations of amorphous silicon, the structure of which allow high electric fields upon application of a bias thereby beneficially resulting in a reduction in noise from contact injection and an increase in signal including avalanche multiplication and gain of the signal produced by incoming high energy radiation. These enhanced radiation sensitive devices can be used as measuring and detection means for visible light, low energy photons and high energy ionizing particles such as electrons, x-rays, alpha particles, beta particles and gamma radiation. Particular utility of the device is disclosed for precision powder crystallography and biological identification. 13 figs.

  3. Radiative-convective instability

    E-Print Network [OSTI]

    Wing, Allison A.

    Radiative-moist-convective equilibrium (RCE) is a simple paradigm for the statistical equilibrium the earth's climate would exhibit in the absence of lateral energy transport. It has generally been assumed that for a given ...

  4. Ionizing radiation detector

    DOE Patents [OSTI]

    Thacker, Louis H. (Knoxville, TN)

    1990-01-01

    An ionizing radiation detector is provided which is based on the principle of analog electronic integration of radiation sensor currents in the sub-pico to nano ampere range between fixed voltage switching thresholds with automatic voltage reversal each time the appropriate threshold is reached. The thresholds are provided by a first NAND gate Schmitt trigger which is coupled with a second NAND gate Schmitt trigger operating in an alternate switching state from the first gate to turn either a visible or audible indicating device on and off in response to the gate switching rate which is indicative of the level of radiation being sensed. The detector can be configured as a small, personal radiation dosimeter which is simple to operate and responsive over a dynamic range of at least 0.01 to 1000 R/hr.

  5. Method of enhancing radiation response of radiation detection materials

    DOE Patents [OSTI]

    Miller, Steven D. (Richland, WA)

    1997-01-01

    The present invention is a method of increasing radiation response of a radiation detection material for a given radiation signal by first pressurizing the radiation detection material. Pressurization may be accomplished by any means including mechanical and/or hydraulic. In this application, the term "pressure" includes fluid pressure and/or mechanical stress.

  6. Radiation Safety Training Basic Radiation Safety Training for

    E-Print Network [OSTI]

    Dai, Pengcheng

    Radiation Safety Training Basic Radiation Safety Training for X-ray Users for Physics 461 & 462 Protocol Title: Basic Radiation Safety Training for X-ray Users Drafted By: Chris Millsaps, RSS Reviewers: ZB, TU, GS Purpose: To provide basic radiation safety training to the users of x-ray producing

  7. Radiation Damage Effects in Candidate Titanates for Pu Disposition: Zirconolite

    SciTech Connect (OSTI)

    Strachan, Denis M.; Scheele, Randall D.; Buck, Edgar C.; Kozelisky, Anne E.; Sell, Rachel L.; Elovich, Robert J.; Buchmiller, William C.

    2008-01-15

    This is the second of two papers on the results of radiation-induced damage accumulation in titanate ceramics that potentially could be used for weapons grade plutonium disposition. In the first paper we discussed the results from pyrochlore (betafite) based ceramics. In this paper, we discuss the effects of radiation-induced damage on the density and crystal structure of a nominally phase-pure zirconolite and two other zirconolite-bearing ceramics from the alpha decay of 238Pu. Macro (bulk) and micro (X-ray diffraction) swelling were found to be temperature independent, whereas the density determined with He gas pycnometry was temperature dependent. It took approximately 740 days (2.6?1018 ?/g) for the specimens to become X-ray amorphouslonger for the swelling to saturate. Unlike what we observed for the pyrochlore-based ceramics, we did not observe any phase changes associated with storage temperature and damage ingrowth. The forward dissolution rate at a pH value of 2 for material containing essentially all zirconolite is 1.7(4)?10-3 g/(m2?d). Very little pH dependence was observed for zirconolite specimens and, like we observed for the pyrochlore-bearing ceramics in this study, there was no dependence on the amount of radiation-induced damage. As with the pyrochlore, these materials did not become substantially friable with increasing radiation-induced damage. Even after the radiation-induced swelling saturated, the specimens remained physically intact with no evidence for microcracking. Thus, the material remains physically a viable material for the disposition of surplus weapons-grade Pu.

  8. Handbook of radiation effects

    SciTech Connect (OSTI)

    Holmes-Siedle, A. (ed.) (Radiation Experiments and Monitors, Oxford (United Kingdom) Univ. of West London (United Kingdom)); Adams, L. (ed.) (European Space Agency-ESTEC, Noordwijk (Netherlands). Radiation Effects and Analysis Techniques Unit)

    1993-01-01

    This handbook is intended to serve as a tool for designers of equipment and scientific instruments in cases where they are required to ensure the survival of the equipment in radiation environments. High-technology materials, especially semiconductors and optics, tend to degrade on exposure to radiation in many different ways. Intense high-energy radiation environments are found in nuclear reactors and accelerators, machines for radiation therapy, industrial sterilization, and space. Some engineers have to build equipment which will survive a nuclear explosion from a hostile source. Proper handling of a disaster with radioactive materials requires equipment which depends utterly on semiconductor microelectronics and imaging devices. Thus the technology of radiation-tolerant electronics is an instrument for good social spheres as diverse as disaster planning and the exploration of Mars. In order to design equipment for intense environments like those described above, then degradation from high-energy irradiation must be seen as a basic design parameter. The aim of this handbook is to assist the engineer or student in that thought; to make it possible to write intelligent specifications; to offer some understanding of the complex variety of effects which occur when high-technology components encounter high-energy radiation; and to go thoroughly into the balance of choices of how to alleviate the effects and hence achieve the design aims of the project. Separate abstracts were prepared for 15 chapters of this book.

  9. Radiation analysis devices, radiation analysis methods, and articles of manufacture

    DOE Patents [OSTI]

    Roybal, Lyle Gene

    2010-06-08

    Radiation analysis devices include circuitry configured to determine respective radiation count data for a plurality of sections of an area of interest and combine the radiation count data of individual of sections to determine whether a selected radioactive material is present in the area of interest. An amount of the radiation count data for an individual section is insufficient to determine whether the selected radioactive material is present in the individual section. An article of manufacture includes media comprising programming configured to cause processing circuitry to perform processing comprising determining one or more correction factors based on a calibration of a radiation analysis device, measuring radiation received by the radiation analysis device using the one or more correction factors, and presenting information relating to an amount of radiation measured by the radiation analysis device having one of a plurality of specified radiation energy levels of a range of interest.

  10. Radiative cooling of C{sub 7}{sup ?}

    SciTech Connect (OSTI)

    Najafian, K.; Pettersson, M. S.; Hansen, K.; Dynefors, B.; Shiromaru, H.; Matsumoto, J.; Tanuma, H.; Furukawa, T.; Azuma, T.

    2014-03-14

    The spontaneous and photo-induced neutralization of C{sub 7}{sup ?} produced in a laser ablation source was measured in an electrostatic storage ring. The measurements provide three independent determinations of the radiative cooling of the ions, based on the short time spontaneous decay and on the integrated amplitude and the shape of the photo-induced neutralization signal. The amplitude of the photo-induced signal was measured between 0.5 ms and 35 ms and found to depend on photon wavelength and ion storage time. All three signals can be reproduced with identical thermal IR radiative cooling rates with oscillator strengths equal to theoretical predictions. In addition, the measurements provide the excitation energy distribution.

  11. Vacuum - induced stationary entanglement in radiatively coupled three - level atoms

    E-Print Network [OSTI]

    L. Derkacz; L. Jakobczyk

    2008-05-05

    We consider a pair of three - level atoms interacting with a common vacuum and analyze the process of entanglement production due to spontaneous emission. We show that in the case of closely separated atoms, collective damping can generate robust entanglement of the asymptotic states.

  12. Modeling progression in radiation-induced lung adenocarcinomas

    E-Print Network [OSTI]

    Fakir, Hatim; Hofmann, Werner; Sachs, Rainer K.

    2010-01-01

    carrying capacity. Indeed, Speer et al. (1984) showed thatdata for tumor growth (Speer et al. 1984). In our study,model. Math Biosci Speer JF, Petrosky VE, Retsky MW,

  13. Radiation-induced mechanical property changes in filled rubber (Journal

    Office of Scientific and Technical Information (OSTI)

    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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfateSciTech ConnectSpeedingConnect Pulse energy(Conference)Article) | SciTech Connect

  14. Radiation-induced mechanical property changes in filled rubber (Journal

    Office of Scientific and Technical Information (OSTI)

    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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfateSciTech ConnectSpeedingConnect Pulse energy(Conference)Article) | SciTech

  15. Radiation-induced mechanical property changes in filled rubber (Journal

    Office of Scientific and Technical Information (OSTI)

    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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfateSciTech ConnectSpeedingConnect Pulse energy(Conference)Article) | SciTechArticle) |

  16. Adaptive-feedback spectral-phase control for interactions with transform-limited ultrashort high-power laser pulses

    E-Print Network [OSTI]

    Umstadter, Donald

    point of a 100-TW peak-power laser in vacuum. The spectral-phase distortion induced by the dispersion that use high-power laser pulses must be performed in vacuum in order to prevent degradation of the laserAdaptive-feedback spectral-phase control for interactions with transform-limited ultrashort high-power

  17. HIF-1 and NDRG2 contribute to hypoxia-induced radioresistance of cervical cancer Hela cells

    SciTech Connect (OSTI)

    Liu, Junye [Department of Radiation Medicine, Fourth Military Medical University, Xi'an (China) [Department of Radiation Medicine, Fourth Military Medical University, Xi'an (China); Department of Biochemistry and Molecular Biology, State Key Laboratory of Cancer Biology, Fourth Military Medical University, Xi'an (China); Zhang, Jing [Department of Biochemistry and Molecular Biology, State Key Laboratory of Cancer Biology, Fourth Military Medical University, Xi'an (China)] [Department of Biochemistry and Molecular Biology, State Key Laboratory of Cancer Biology, Fourth Military Medical University, Xi'an (China); Wang, Xiaowu [Department of Radiation Medicine, Fourth Military Medical University, Xi'an (China)] [Department of Radiation Medicine, Fourth Military Medical University, Xi'an (China); Li, Yan [Department of Biochemistry and Molecular Biology, State Key Laboratory of Cancer Biology, Fourth Military Medical University, Xi'an (China)] [Department of Biochemistry and Molecular Biology, State Key Laboratory of Cancer Biology, Fourth Military Medical University, Xi'an (China); Chen, Yongbin; Li, Kangchu [Department of Radiation Medicine, Fourth Military Medical University, Xi'an (China)] [Department of Radiation Medicine, Fourth Military Medical University, Xi'an (China); Zhang, Jian [Department of Biochemistry and Molecular Biology, State Key Laboratory of Cancer Biology, Fourth Military Medical University, Xi'an (China)] [Department of Biochemistry and Molecular Biology, State Key Laboratory of Cancer Biology, Fourth Military Medical University, Xi'an (China); Yao, Libo, E-mail: bioyao@fmmu.edu.cn [Department of Biochemistry and Molecular Biology, State Key Laboratory of Cancer Biology, Fourth Military Medical University, Xi'an (China)] [Department of Biochemistry and Molecular Biology, State Key Laboratory of Cancer Biology, Fourth Military Medical University, Xi'an (China); Guo, Guozhen, E-mail: guozhengg@hotmail.com [Department of Radiation Medicine, Fourth Military Medical University, Xi'an (China)] [Department of Radiation Medicine, Fourth Military Medical University, Xi'an (China)

    2010-07-15

    Hypoxia inducible factor 1 (HIF-1), the key mediator of hypoxia signaling pathways, has been shown involved in hypoxia-induced radioresistance. However, the underlying mechanisms are unclear. The present study demonstrated that both hypoxia and hypoxia mimetic cobalt chloride could increase the radioresistance of human cervical cancer Hela cells. Meanwhile, ectopic expression of HIF-1 could enhance the resistance of Hela cells to radiation, whereas knocking-down of HIF-1 could increase the sensitivity of Hela cells to radiation in the presence of hypoxia. N-Myc downstream-regulated gene 2 (NDRG2), a new HIF-1 target gene identified in our lab, was found to be upregulated by hypoxia and radiation in a HIF-1-dependent manner. Overexpression of NDRG2 resulted in decreased sensitivity of Hela cells to radiation while silencing NDRG2 led to radiosensitization. Moreover, NDRG2 was proved to protect Hela cells from radiation-induced apoptosis and abolish radiation-induced upregulation of Bax. Taken together, these data suggest that both HIF-1 and NDRG2 contribute to hypoxia-induced tumor radioresistance and that NDRG2 acts downstream of HIF-1 to promote radioresistance through suppressing radiation-induced Bax expression. It would be meaningful to further explore the clinical application potential of HIF-1 and NDRG2 blockade as radiosensitizer for tumor therapy.

  18. COLUMBIA UNIVERSITY Radiation Safety Program

    E-Print Network [OSTI]

    Jia, Songtao

    this form to Radiation Safety's Dosimetry Program.) ___ Yes ___ No 1. Was the Dosimeter placed or stored

  19. Radiation oncogenesis in cell culture

    SciTech Connect (OSTI)

    Borek, C.

    1982-01-01

    This review article examines the oncogenic effects of radiation with emphasis on ionizing radiations. Cell transformation in vitro is examined with respect to culture systems currently used in these studies, initiation and phenotypic expression of transformation and criteria for transformation. The section of radiation oncogenesis in vitro includes ionizing and nonionizing radiation studies and cocarcinogens and modulators of radiogenic transformations.

  20. REPORT NO. 8 radiation hazards

    E-Print Network [OSTI]

    REPORT NO. 8 REVISED guidance for the control of radiation hazards in uranium mining SEPTEMBER 1967 OF RADIATION HAZARDS IN URANIUM MINING SEPTEMBER 1967 Staff Report of the FEDERAL RADIATION COUNCIL #12;FEDERAL...... .... .._ _.... Section I. Introduction. . . Section II. The Radiation Environment AssociatedWith Uranium Mining. Section

  1. Supplementary Material Learning optimal adaptation strategies in unpredictable motor tasks

    E-Print Network [OSTI]

    Supplementary Material Learning optimal adaptation strategies in unpredictable motor tasks D.A. Braun, A. Aertsen, D.M. Wolpert, C. Mehring Contents 1 Adaptive Optimal Control Methods 2 1-adaptive Optimal Control Models . . . . . . . . . . . . . . . . . 5 1.4 Arm Model

  2. Unifying the Sensory and Motor Components of Sensorimotor Adaptation

    E-Print Network [OSTI]

    Haith, Adrian; Jackson, Carl; Miall, Chris; Vijayakumar, Sethu

    2008-01-01

    Adaptation of visually guided reaching movements in novel visuomotor environments (e.g. wearing prism goggles) comprises not only motor adaptation but also substantial sensory adaptation, corresponding to shifts in ...

  3. Probing young massive clusters with laser guide star adaptive optics

    E-Print Network [OSTI]

    McCrady, Nate

    2009-01-01

    laser guide star adaptive optics Nate McCrady Received: 10laser guide star adaptive optics (LGS/AO) on the 10 m Keckof 4 Mpc. Our adaptive optics work is motivated by three

  4. 2014 DOE Climate Change Adaptation Plan | Department of Energy

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

    2014 DOE Climate Change Adaptation Plan 2014 DOE Climate Change Adaptation Plan Document presents the U.S. Department of Energy (DOE) 2014 plan for adapting to climate change....

  5. Adaptive Expertise and Contextualized Activities in Computer Aided Design

    E-Print Network [OSTI]

    Ozturk, Elif

    2015-05-04

    , to determine the baseline adaptive expertise among the sample population, an adaptive expertise survey (AES) instrument is administered to both the practicing engineers and the students. The instrument contains questions defining four dimensions of adaptive...

  6. Ultrafast laser-induced changes in optical properties of semiconductors

    SciTech Connect (OSTI)

    Chirila, C. C.; Lim, Freda C. H.; Gavaza, M. G. [Institute of High Performance Computing, 1 Fusionopolis Way, 16-16 Connexis, 138632 (Singapore)

    2012-04-01

    We study the effect of laser radiation on optical properties of semiconductors of industrial interest. The material is pumped with a laser of chosen central frequency, for which the absorption is maximal, thus inducing electron dynamics, which modifies the optical properties. By using an improved theoretical model, we study ultrafast dynamic changes in the refraction index and reflectivity corresponding to a wide frequency-interval of probing radiation and identify that interval where these optical changes are most significant.

  7. Diffusive radiation in Langmuir turbulence produced by jet shocks

    E-Print Network [OSTI]

    Fleishman, Gregory D

    2007-01-01

    Anisotropic distributions of charged particles including two-stream distributions give rise to generation of either stochastic electric fields (in the form of Langmuir waves, Buneman instability) or random quasi-static magnetic fields (Weibel and filamentation instabilities) or both. These two-stream instabilities are known to play a key role in collisionless shock formation, shock-shock interactions, and shock-induced electromagnetic emission. This paper applies the general non-perturbative stochastic theory of radiation to study electromagnetic emission produced by relativistic particles, which random walk in the stochastic electric fields of the Langmuir waves. This analysis takes into account the cumulative effect of uncorrelated Langmuir waves on the radiating particle trajectory giving rise to angular diffusion of the particle, which eventually modifies the corresponding radiation spectra. We demonstrate that the radiative process considered is probably relevant for emission produced in various kinds of...

  8. NCRAWL: Network Coding for Rate Adaptive Wireless Links

    E-Print Network [OSTI]

    Broustis, Ioannis; Syrivelis, Dimitris; Georgiadis, Leonidas; Tassiulas, Leandros

    2011-01-01

    Intersession network coding (NC) can provide significant performance benefits via mixing packets at wireless routers; these benefits are especially pronounced when NC is applied in conjunction with intelligent link scheduling. NC however imposes certain processing operations, such as encoding, decoding, copying and storage. When not utilized carefully, all these operations can induce tremendous processing overheads in practical, wireless, multi-rate settings. Our measurements with prior NC implementations suggest that such processing operations severely degrade the router throughput, especially at high bit rates. Motivated by this, we design {\\bf NCRAWL}, a Network Coding framework for Rate Adaptive Wireless Links. The design of NCRAWL facilitates low overhead NC functionalities, thereby effectively approaching the theoretically expected capacity benefits of joint NC and scheduling. We implement and evaluate NCRAWL on a wireless testbed. Our experiments demonstrate that NCRAWL meets the theoretical predicted ...

  9. Adaptive characterization of coherent states

    E-Print Network [OSTI]

    Markku P. V. Stenberg; Kevin Pack; Frank K. Wilhelm

    2015-08-18

    We present methods for efficient characterization of an optical coherent state $|\\alpha\\rangle$. We choose measurement settings adaptively and stochastically, based on data while it is collected. Our algorithm divides the estimation in two distinct steps: (i) Before the first detection of vacuum state, the probability of choosing a measurement setting is proportional to detecting vacuum with the setting, which makes using too similar measurement settings twice unlikely and (ii) after the first detection of vacuum, we focus measurements in the region where vacuum is most likely to be detected. In step (i) [(ii)] the detection of vacuum (a photon) has a significantly larger effect on the shape of the posterior probability distribution of $\\alpha$. Compared to nonadaptive schemes, our method makes the number of measurement shots required to achieve certain level of accuracy smaller approximately by a factor proportional to the area describing the initial uncertainty of $\\alpha$ in phase space. While this algorithm is not directly robust against readout errors, we make it such by introducing repeated measurements in the step (i).

  10. Analysis of beam loss induced abort kicker instability

    SciTech Connect (OSTI)

    Zhang W.; Sandberg, J.; Ahrens, L.; Fischer, W.; Hahn, H.; Mi, J.; Pai, C.; Tan, Y.

    2012-05-20

    Through more than a decade of operation, we have noticed the phenomena of beam loss induced kicker instability in the RHIC beam abort systems. In this study, we analyze the short term beam loss before abort kicker pre-fire events and operation conditions before capacitor failures. Beam loss has caused capacitor failures and elevated radiation level concentrated at failed end of capacitor has been observed. We are interested in beam loss induced radiation and heat dissipation in large oil filled capacitors and beam triggered thyratron conduction. We hope the analysis result would lead to better protection of the abort systems and improved stability of the RHIC operation.

  11. Packet personal radiation monitor

    DOE Patents [OSTI]

    Phelps, J.E.

    1988-03-31

    A personal radiation monitor of the chirper type is provided for detecting ionizing radiation. A battery powered high voltage power supply is used to generate and apply a high voltage bias to a G-M tube radiation sensor. The high voltage is monitored by a low-loss sensing network which generates a feedback signal to control the high voltage power supply such that the high voltage bias is recharged to +500 VDC when the current pulses of the sensor, generated by the detection of ionizing radiatonevents, discharges the high voltage bias to +450 VDC. During the high voltage recharge period an audio transducer is activated to produce an audible ''chirp''. The rate of the ''chirps'' is controlled by the rate at which the high voltage bias is recharged, which is proportional to the radiation field intensity to which the sensor is exposed. The chirp rate sensitivity is set to be approximately 1.5 (chirps/min/MR/hr.). The G-M tube sensor is used in a current sensing mode so that the device does not paralyze in a high radiation field. 2 figs.

  12. Remote radiation dosimetry

    DOE Patents [OSTI]

    Braunlich, Peter F. (Pullman, WA); Tetzlaff, Wolfgang (Pullman, WA); Hegland, Joel E. (Pullman, WA); Jones, Scott C. (Pullman, WA)

    1991-01-01

    Disclosed are methods and apparatus for remotely measuring radiation levels. Such are particularly useful for measuring relatively high levels or dosages of radiation being administered in radiation therapy. They are also useful for more general radiation level measurements where remote sensing from the remaining portions of the apparatus is desirable. The apparatus uses a beam generator, such as a laser beam, to provide a stimulating beam. The stimulating beam is preferably of wavelengths shorter than 6 microns, or more advantageously less than 2 microns. The stimulating beam is used to stimulate a remote luminescent sensor mounted in a probe which emits stored luminescent energy resulting from exposure of the sensor to ionizing radiation. The stimulating beam is communicated to the remote luminescent sensor via transmissive fiber which also preferably serves to return the emission from the luminescent sensor. The stimulating beam is advantageously split by a beam splitter to create a detector beam which is measured for power during a reading period during which the luminescent phosphor is read. The detected power is preferably used to control the beam generator to thus produce desired beam power during the reading period. The luminescent emission from the remote sensor is communicated to a suitable emission detector, preferably after filtering or other selective treatment to better isolate the luminescent emission.

  13. Remote radiation dosimetry

    DOE Patents [OSTI]

    Braunlich, P.F.; Tetzlaff, W.; Hegland, J.E.; Jones, S.C.

    1991-03-12

    Disclosed are methods and apparatus for remotely measuring radiation levels. Such are particularly useful for measuring relatively high levels or dosages of radiation being administered in radiation therapy. They are also useful for more general radiation level measurements where remote sensing from the remaining portions of the apparatus is desirable. The apparatus uses a beam generator, such as a laser beam, to provide a stimulating beam. The stimulating beam is preferably of wavelengths shorter than 6 microns, or more advantageously less than 2 microns. The stimulating beam is used to stimulate a remote luminescent sensor mounted in a probe which emits stored luminescent energy resulting from exposure of the sensor to ionizing radiation. The stimulating beam is communicated to the remote luminescent sensor via a transmissive fiber which also preferably serves to return the emission from the luminescent sensor. The stimulating beam is advantageously split by a beam splitter to create a detector beam which is measured for power during a reading period during which the luminescent phosphor is read. The detected power is preferably used to control the beam generator to thus produce desired beam power during the reading period. The luminescent emission from the remote sensor is communicated to a suitable emission detector, preferably after filtering or other selective treatment to better isolate the luminescent emission. 8 figures.

  14. Fossil Energy-Developed Fuel Cell Technology Being Adapted by...

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

    Fossil Energy-Developed Fuel Cell Technology Being Adapted by Navy for Advanced Unmanned Undersea Vehicles Fossil Energy-Developed Fuel Cell Technology Being Adapted by Navy for...

  15. Anisoplanatism in adaptive optics systems due to pupil aberrations...

    Office of Scientific and Technical Information (OSTI)

    Anisoplanatism in adaptive optics systems due to pupil aberrations Citation Details In-Document Search Title: Anisoplanatism in adaptive optics systems due to pupil aberrations...

  16. Adapting On-Site Electrical Generation Platforms for Producer...

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

    Adapting On-Site Electrical Generation Platforms for Producer Gas - Fact Sheet, April 2014 Adapting On-Site Electrical Generation Platforms for Producer Gas - Fact Sheet, April...

  17. Enabling High Efficiency Low Temperature Combustion by Adaptive...

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

    Low Temperature Combustion by Adaptive In-Situ Jet Cooling Enabling High Efficiency Low Temperature Combustion by Adaptive In-Situ Jet Cooling A new approach, called...

  18. Kenya-Strengthening Adaptation and Resilience to Climate Change...

    Open Energy Info (EERE)

    Kenya-Strengthening Adaptation and Resilience to Climate Change(StARCK) (Redirected from Strengthening Adaptation and Resilience to Climate Change in Kenya (StARCK)) Jump to:...

  19. India-Vulnerability Assessment and Enhancing Adaptive Capacities...

    Open Energy Info (EERE)

    India-Vulnerability Assessment and Enhancing Adaptive Capacities to Climate Change Jump to: navigation, search Name India-Vulnerability Assessment and Enhancing Adaptive Capacities...

  20. Adaptation to Climate Variability and Change: A Guidance Manual...

    Open Energy Info (EERE)

    Adaptation to Climate Variability and Change: A Guidance Manual for Development Planning Jump to: navigation, search Tool Summary LAUNCH TOOL Name: Adaptation to Climate...

  1. An adaptive mesh refinement technique for dynamics of solids

    E-Print Network [OSTI]

    Trivedi, Abhishek

    2007-01-01

    adaptations; right: cut-off grid with a solution contour.adaptations; right: cut-off grid with a solution contour.

  2. An adaptive sparse-grid-based iterative ensemble Kalman filter...

    Office of Scientific and Technical Information (OSTI)

    An adaptive sparse-grid-based iterative ensemble Kalman filter approach for parameter field estimation Citation Details In-Document Search Title: An adaptive sparse-grid-based...

  3. Financing Climate Adaptation and Mitigation in Rural Areas of...

    Open Energy Info (EERE)

    Financing Climate Adaptation and Mitigation in Rural Areas of Developing Countries Jump to: navigation, search Tool Summary LAUNCH TOOL Name: Financing Climate Adaptation and...

  4. Composition for radiation shielding

    DOE Patents [OSTI]

    Kronberg, J.W.

    1994-08-02

    A composition for use as a radiation shield is disclosed. The shield has a depleted uranium core for absorbing gamma rays and a bismuth coating for preventing chemical corrosion and absorbing gamma rays. Alternatively, a sheet of gadolinium may be positioned between the uranium core and the bismuth coating for absorbing neutrons. The composition is preferably in the form of a container for storing materials that emit radiation such as gamma rays and neutrons. The container is preferably formed by casting bismuth around a pre-formed uranium container having a gadolinium sheeting, and allowing the bismuth to cool. The resulting container is a structurally sound, corrosion-resistant, radiation-absorbing container. 2 figs.

  5. Pediatric radiation oncology

    SciTech Connect (OSTI)

    Halperin, E.C.; Kun, L.E.; Constine, L.S.; Tarbell, N.J.

    1989-01-01

    This text covers all aspects of radiation therapy for treatment of pediatric cancer. The book describes the proper use of irradiation in each of the malignancies of childhood, including tumors that are rarely encountered in adult practice. These include acute leukemia; supratentorial brain tumors; tumors of the posterior fossa of the brain and spinal canal; retinoblastoma and optic nerve glioma; neuroblastoma; Hodgkin's disease; malignant lymphoma; Ewing's sarcoma; osteosarcoma; rhabdomyosarcoma; Desmoid tumor; Wilms' tumor; liver and biliary tumors; germ cell and stromal cell tumors of the gonads; endocrine, aerodigestive tract, and breast tumors; Langerhans' cell histiocytosis; and skin cancer and hemangiomas. For each type of malignancy, the authors describe the epidemiology, common presenting signs and symptoms, staging, and proper diagnostic workup. Particular attention is given to the indications for radiation therapy and the planning of a course of radiotherapy, including the optimal radiation dose, field size, and technique.

  6. Semiconductor radiation detector

    DOE Patents [OSTI]

    Bell, Zane W. (Oak Ridge, TN); Burger, Arnold (Knoxville, TN)

    2010-03-30

    A semiconductor detector for ionizing electromagnetic radiation, neutrons, and energetic charged particles. The detecting element is comprised of a compound having the composition I-III-VI.sub.2 or II-IV-V.sub.2 where the "I" component is from column 1A or 1B of the periodic table, the "II" component is from column 2B, the "III" component is from column 3A, the "IV" component is from column 4A, the "V" component is from column 5A, and the "VI" component is from column 6A. The detecting element detects ionizing radiation by generating a signal proportional to the energy deposited in the element, and detects neutrons by virtue of the ionizing radiation emitted by one or more of the constituent materials subsequent to capture. The detector may contain more than one neutron-sensitive component.

  7. Radiation tolerance of nanocrystalline ceramics: Insights from yttria stabilized zirconia

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

    Dey, Sanchita; Drazin, John W.; Wang, Yongqiang; Valdez, James A.; Holesinger, Terry G.; Uberuaga, Blas P.; Castro, Ricardo H. R.

    2015-01-13

    Materials for applications in hostile environments, such as nuclear reactors or radioactive waste immobilization, require extremely high resistance to radiation damage, such as resistance to amorphization or volume swelling. Nanocrystalline materials have been reported to present exceptionally high radiation-tolerance to amorphization. In principle, grain boundaries that are prevalent in nanomaterials could act as sinks for point-defects, enhancing defect recombination. In this paper we present evidence for this mechanism in nanograined Yttria Stabilized Zirconia (YSZ), associated with the observation that the concentration of defects after irradiation using heavy ions (Kr?, 400 keV) is inversely proportional to the grain size. HAADF imagesmoresuggest the short migration distances in nanograined YSZ allow radiation induced interstitials to reach the grain boundaries on the irradiation time scale, leaving behind only vacancy clusters distributed within the grain. Because of the relatively low temperature of the irradiations and the fact that interstitials diffuse thermally more slowly than vacancies, this result indicates that the interstitials must reach the boundaries directly in the collision cascade, consistent with previous simulation results. Concomitant radiation-induced grain growth was observed which, as a consequence of the non-uniform implantation, caused cracking of the nano-samples induced by local stresses at the irradiated/non-irradiated interfaces.less

  8. Radiative Magnetic Reconnection in Astrophysics

    E-Print Network [OSTI]

    Uzdensky, Dmitri A

    2015-01-01

    I review a new rapidly growing area of high-energy plasma astrophysics --- radiative magnetic reconnection, i.e., a reconnection regime where radiation reaction influences reconnection dynamics, energetics, and nonthermal particle acceleration. This influence be may be manifested via a number of astrophysically important radiative effects, such as radiation-reaction limits on particle acceleration, radiative cooling, radiative resistivity, braking of reconnection outflows by radiation drag, radiation pressure, viscosity, and even pair creation at highest energy densities. Self-consistent inclusion of these effects in magnetic reconnection theory and modeling calls for serious modifications to our overall theoretical approach to the problem. In addition, prompt reconnection-powered radiation often represents our only observational diagnostic tool for studying remote astrophysical systems; this underscores the importance of developing predictive modeling capabilities to connect the underlying physical condition...

  9. ATHENA radiation model

    SciTech Connect (OSTI)

    Shumway, R.W.

    1987-10-01

    The ATHENA computer program has many features that make it desirable to use as a space reactor evaluation tool. One of the missing features was a surface-to-surface thermal radiation model. A model was developed that allows any of the regular ATHENA heat slabs to radiate to any other heat slab. The view factors and surface emissivities must be specified by the user. To verify that the model was properly accounting for radiant energy transfer, two different types of test calculations were performed. Both calculations have excellent results. The updates have been used on both the INEL CDC-176 and the Livermore Cray. 7 refs., 2 figs., 6 tabs.

  10. Wireless passive radiation sensor

    DOE Patents [OSTI]

    Pfeifer, Kent B; Rumpf, Arthur N; Yelton, William G; Limmer, Steven J

    2013-12-03

    A novel measurement technique is employed using surface acoustic wave (SAW) devices, passive RF, and radiation-sensitive films to provide a wireless passive radiation sensor that requires no batteries, outside wiring, or regular maintenance. The sensor is small (<1 cm.sup.2), physically robust, and will operate unattended for decades. In addition, the sensor can be insensitive to measurement position and read distance due to a novel self-referencing technique eliminating the need to measure absolute responses that are dependent on RF transmitter location and power.

  11. Radiation monitor for liquids

    DOE Patents [OSTI]

    Koster, J.E.; Bolton, R.D.

    1999-03-02

    A radiation monitor for use with liquids that utilizes air ions created by alpha radiation emitted by the liquids as its detectable element. A signal plane, held at an electrical potential with respect to ground, collects these air ions. A guard plane or guard rings is used to limit leakage currents. In one embodiment, the monitor is used for monitoring liquids retained in a tank. Other embodiments monitor liquids flowing through a tank, and bodies of liquids, such as ponds, lakes, rivers and oceans. 4 figs.

  12. Radiation monitor for liquids

    DOE Patents [OSTI]

    Koster, James E. (Los Alamos, NM); Bolton, Richard D. (Los Alamos, NM)

    1999-01-01

    A radiation monitor for use with liquids that utilizes air ions created by alpha radiation emitted by the liquids as its detectable element. A signal plane, held at an electrical potential with respect to ground, collects these air ions. A guard plane or guard rings is used to limit leakage currents. In one embodiment, the monitor is used for monitoring liquids retained in a tank. Other embodiments monitor liquids flowing through a tank, and bodies of liquids, such as ponds, lakes, rivers and oceans.

  13. Adaptive nonlocal means filtering based on local noise level for CT denoising

    SciTech Connect (OSTI)

    Li, Zhoubo; Trzasko, Joshua D.; Lake, David S.; Blezek, Daniel J.; Manduca, Armando; Yu, Lifeng; Fletcher, Joel G.; McCollough, Cynthia H.

    2014-01-15

    Purpose: To develop and evaluate an image-domain noise reduction method based on a modified nonlocal means (NLM) algorithm that is adaptive to local noise level of CT images and to implement this method in a time frame consistent with clinical workflow. Methods: A computationally efficient technique for local noise estimation directly from CT images was developed. A forward projection, based on a 2D fan-beam approximation, was used to generate the projection data, with a noise model incorporating the effects of the bowtie filter and automatic exposure control. The noise propagation from projection data to images was analytically derived. The analytical noise map was validated using repeated scans of a phantom. A 3D NLM denoising algorithm was modified to adapt its denoising strength locally based on this noise map. The performance of this adaptive NLM filter was evaluated in phantom studies in terms of in-plane and cross-plane high-contrast spatial resolution, noise power spectrum (NPS), subjective low-contrast spatial resolution using the American College of Radiology (ACR) accreditation phantom, and objective low-contrast spatial resolution using a channelized Hotelling model observer (CHO). Graphical processing units (GPU) implementation of this noise map calculation and the adaptive NLM filtering were developed to meet demands of clinical workflow. Adaptive NLM was piloted on lower dose scans in clinical practice. Results: The local noise level estimation matches the noise distribution determined from multiple repetitive scans of a phantom, demonstrated by small variations in the ratio map between the analytical noise map and the one calculated from repeated scans. The phantom studies demonstrated that the adaptive NLM filter can reduce noise substantially without degrading the high-contrast spatial resolution, as illustrated by modulation transfer function and slice sensitivity profile results. The NPS results show that adaptive NLM denoising preserves the shape and peak frequency of the noise power spectrum better than commercial smoothing kernels, and indicate that the spatial resolution at low contrast levels is not significantly degraded. Both the subjective evaluation using the ACR phantom and the objective evaluation on a low-contrast detection task using a CHO model observer demonstrate an improvement on low-contrast performance. The GPU implementation can process and transfer 300 slice images within 5 min. On patient data, the adaptive NLM algorithm provides more effective denoising of CT data throughout a volume than standard NLM, and may allow significant lowering of radiation dose. After a two week pilot study of lower dose CT urography and CT enterography exams, both GI and GU radiology groups elected to proceed with permanent implementation of adaptive NLM in their GI and GU CT practices. Conclusions: This work describes and validates a computationally efficient technique for noise map estimation directly from CT images, and an adaptive NLM filtering based on this noise map, on phantom and patient data. Both the noise map calculation and the adaptive NLM filtering can be performed in times that allow integration with clinical workflow. The adaptive NLM algorithm provides effective denoising of CT data throughout a volume, and may allow significant lowering of radiation dose.

  14. Robust adaptive control of switched systems

    E-Print Network [OSTI]

    El-Rifai, Khalid, 1979-

    2007-01-01

    In this thesis, robust adaptive controllers are developed for classes of switched nonlinear systems. Switched systems are those governed by differential equations, which undergo vector field switching due to sudden changes ...

  15. Adaptive control of a generic hypersonic vehicle

    E-Print Network [OSTI]

    Wiese, Daniel Philip

    2013-01-01

    This thesis presents a an adaptive augmented, gain-scheduled baseline LQR-PI controller applied to the Road Runner six-degree-of-freedom generic hypersonic vehicle model. Uncertainty in control effectiveness, longitudinal ...

  16. Adaptive FE Methods for Conservation Equations

    E-Print Network [OSTI]

    Hartmann, Ralf

    Adaptive FE Methods for Conservation Equations Ralf Hartmann Abstract. We present an approach, University of Heidelberg. #12; 2 R. Hartmann by parts on each cell K results in X K2Th h (F (u); rv)K + (F (u

  17. Developmental Plasticity Links Local Adaptation and Evolutionary

    E-Print Network [OSTI]

    Badyaev, Alex

    Developmental Plasticity Links Local Adaptation and Evolutionary Diversification in Foraging, University of Arizona, Tucson, Arizona Developmental plasticity is thought to reconcile the constraining role morphology into adulthood, providing an opportunity to directly examine the links between plasticity of bone

  18. Convert! : the adaptive reuse of churches

    E-Print Network [OSTI]

    Kiley, Christopher John, 1972-

    2004-01-01

    This thesis examines the phenomenon of vacated churches and analyzes the major issues underlying their adaptive reuse in order to help promulgate an awareness of the range of successful strategies and solutions that are ...

  19. Adaptive sampling in autonomous marine sensor networks

    E-Print Network [OSTI]

    Eickstedt, Donald Patrick

    2006-01-01

    In this thesis, an innovative architecture for real-time adaptive and cooperative control of autonomous sensor platforms in a marine sensor network is described in the context of the autonomous oceanographic network scenario. ...

  20. PERSPECTIVE Climate change, adaptation, and phenotypic plasticity

    E-Print Network [OSTI]

    Hendry, Andrew

    PERSPECTIVE Climate change, adaptation, and phenotypic plasticity: the problem and the evidence plasticity, natural selection Correspondence Juha Merila, Ecological Genetics Research Unit, Department distinguish whether phenotypic changes are genetically based or the result of phenotypic plasticity. Second

  1. Collaborative Adaptive Science for Self Reliance

    E-Print Network [OSTI]

    Tate, Kenneth

    (Koyukuk) Clean water (Iguigig) Salmon fishing (Nikolai) Shared Issues: High cost of energy other #12; Historically adaptive. Confluence of increased gas and food prices, reduction in state Potential improvements Benefits of experience Improve self reliance? Future partnerships Other

  2. ADAPTIVE DISCRETIZATION OF AN INTEGRODIFFERENTIAL EQUATION

    E-Print Network [OSTI]

    Larsson, Stig

    ADAPTIVE DISCRETIZATION OF AN INTEGRO­DIFFERENTIAL EQUATION MODELING QUASI­STATIC FRACTIONAL ORDER VISCOELASTICITY Klas Adolfsson # Mikael Enelund ## Stig Larsson ### # Department of Applied Mechanics, Chalmers Mechanics, Chalmers University of Technology, SE--412 96 G?oteborg, Sweden, mikael

  3. Skeletal adaptation to reduced mechanical loading

    E-Print Network [OSTI]

    Eliman, Rachel

    2014-01-01

    Bone adapts its mass and architecture in response to its mechanical environment. Yet control of this process by mechanical cues is poorly understood, particularly for unloading. Defining the fundamental mechanoregulation ...

  4. Adaptive Java Optimisation using machine learning techniques

    E-Print Network [OSTI]

    Long, Shun

    approach are implemented in a prototype Adaptive Optimisation Framework for Java (AOF-Java). The experimental results show that the heuristic random search algorithm can find, within a relatively small number of atttempts, good points in the large...

  5. Adaptive Grids for Atmospheric General Circulation Models

    E-Print Network [OSTI]

    Jablonowski, Christiane

    the wind speed OMEGA model Courtesy of A. Sarma (SAIC, NC, USA) #12;Two Adaptive Shallow Water Models AMR the vertical resolutions adds another factor of 2 We need to increase our computational power by a factor

  6. Climate Change: High Water Impacts and Adaptation

    E-Print Network [OSTI]

    Sheridan, Jennifer

    Climate Change: High Water Impacts and Adaptation David S. Liebl and Kenneth W. Potter Co of global climate change WICCI Stormwater Working Group #12;Projected Climate Change 200-2100 What Global

  7. Scalable Adaptive Multilevel Solvers for Multiphysics Problems

    SciTech Connect (OSTI)

    Xu, Jinchao

    2014-12-01

    In this project, we investigated adaptive, parallel, and multilevel methods for numerical modeling of various real-world applications, including Magnetohydrodynamics (MHD), complex fluids, Electromagnetism, Navier-Stokes equations, and reservoir simulation. First, we have designed improved mathematical models and numerical discretizaitons for viscoelastic fluids and MHD. Second, we have derived new a posteriori error estimators and extended the applicability of adaptivity to various problems. Third, we have developed multilevel solvers for solving scalar partial differential equations (PDEs) as well as coupled systems of PDEs, especially on unstructured grids. Moreover, we have integrated the study between adaptive method and multilevel methods, and made significant efforts and advances in adaptive multilevel methods of the multi-physics problems.

  8. Adaptive Basis Sampling for Smoothing Splines

    E-Print Network [OSTI]

    Zhang, Nan

    2015-08-03

    . However, the high computational cost of smoothing splines for large data sets has hindered their wide application. We develop a new method, named adaptive basis sampling, for efficient computation of smoothing splines in super-large samples. Generally, a...

  9. Human adaptation of avian influenza viruses

    E-Print Network [OSTI]

    Srinivasan, Karunya

    2012-01-01

    Human adaptation of avian influenza viruses pose an enormous public health challenge as the human population is predominantly naive to avian influenza antigens. As such, constant surveillance is needed to monitor the ...

  10. Damage-tolerant nanotwinned metals with nanovoids under radiation environments

    SciTech Connect (OSTI)

    Chen, Y.; Yu, K. Y.; Liu, Y.; Shao, S.; Wang, H.; Kirk, M. A.; Wang, J.; Zhang, X.

    2015-04-24

    Material performance in extreme radiation environments is central to the design of future nuclear reactors. Radiation induces significant damage in the form of dislocation loops and voids in irradiated materials, and continuous radiation often leads to void growth and subsequent void swelling in metals with low stacking fault energy. Here we show that by using in situ heavy ion irradiation in a transmission electron microscope, pre-introduced nanovoids in nanotwinned Cu efficiently absorb radiation-induced defects accompanied by gradual elimination of nanovoids, enhancing radiation tolerance of Cu. In situ studies and atomistic simulations reveal that such remarkable self-healing capability stems from high density of coherent and incoherent twin boundaries that rapidly capture and transport point defects and dislocation loops to nanovoids, which act as storage bins for interstitial loops. This study describes a counterintuitive yet significant concept: deliberate introduction of nanovoids in conjunction with nanotwins enables unprecedented damage tolerance in metallic materials.

  11. The Durham ELT adaptive optics simulation platform

    E-Print Network [OSTI]

    Alastair Basden; Timothy Butterley; Richard Myers; Richard Wilson

    2006-11-09

    Adaptive optics systems are essential on all large telescopes where image quality is important. These are complex systems with many design parameters requiring optimisation before good performance can be achieved. The simulation of adaptive optics systems is therefore necessary to categorise the expected performance. This paper describes an adaptive optics simulation platform, developed at Durham University, which can be used to simulate adaptive optics systems on the largest proposed future extremely large telescopes (ELTs) as well as current systems. This platform is modular, object oriented and has the benefit of hardware application acceleration which can be used to improve the simulation performance, essential for ensuring that the run time of a given simulation is acceptable. The simulation platform described here can be highly parallelised using parallelisation techniques suited for adaptive optics simulation, whilst still offering the user complete control while the simulation is running. Results from the simulation of a ground layer adaptive optics system are provided as an example to demonstrate the flexibility of this simulation platform.

  12. Gadolinium-doped water cerenkov-based neutron and high energy gamma-ray detector and radiation portal monitoring system

    SciTech Connect (OSTI)

    Dazeley, Steven A; Svoboda, Robert C; Bernstein, Adam; Bowden, Nathaniel

    2013-02-12

    A water Cerenkov-based neutron and high energy gamma ray detector and radiation portal monitoring system using water doped with a Gadolinium (Gd)-based compound as the Cerenkov radiator. An optically opaque enclosure is provided surrounding a detection chamber filled with the Cerenkov radiator, and photomultipliers are optically connected to the detect Cerenkov radiation generated by the Cerenkov radiator from incident high energy gamma rays or gamma rays induced by neutron capture on the Gd of incident neutrons from a fission source. The PMT signals are then used to determine time correlations indicative of neutron multiplicity events characteristic of a fission source.

  13. Radiation detector spectrum simulator

    DOE Patents [OSTI]

    Wolf, Michael A. (Los Alamos, NM); Crowell, John M. (Los Alamos, NM)

    1987-01-01

    A small battery operated nuclear spectrum simulator having a noise source nerates pulses with a Gaussian distribution of amplitudes. A switched dc bias circuit cooperating therewith generates several nominal amplitudes of such pulses and a spectral distribution of pulses that closely simulates the spectrum produced by a radiation source such as Americium 241.

  14. Radiation detector spectrum simulator

    DOE Patents [OSTI]

    Wolf, M.A.; Crowell, J.M.

    1985-04-09

    A small battery operated nuclear spectrum simulator having a noise source generates pulses with a Gaussian distribution of amplitudes. A switched dc bias circuit cooperating therewith to generate several nominal amplitudes of such pulses and a spectral distribution of pulses that closely simulates the spectrum produced by a radiation source such as Americium 241.

  15. Radiation Source Replacement Workshop

    SciTech Connect (OSTI)

    Griffin, Jeffrey W.; Moran, Traci L.; Bond, Leonard J.

    2010-12-01

    This report summarizes a Radiation Source Replacement Workshop in Houston Texas on October 27-28, 2010, which provided a forum for industry and researchers to exchange information and to discuss the issues relating to replacement of AmBe, and potentially other isotope sources used in well logging.

  16. Thermal radiation Ron Zevenhoven

    E-Print Network [OSTI]

    Zevenhoven, Ron

    .00032, similarly for 2T = 0.72500 = 1750 mK4 this gives f0-2 = 0.03392. Thus for 0.4 - 0.7 m, f1-2 = 0Thermal radiation revisited Ron Zevenhoven bo Akademi University Thermal and Flow Engineering Laboratory / Vrme- och strmningsteknik tel. 3223 ; ron.zevenhoven@abo.fi Process Engineering

  17. Three Dimensional Radiative Transfer

    E-Print Network [OSTI]

    Tom Abel

    2000-05-09

    Radiative Transfer (RT) effects play a crucial role in the thermal history of the intergalactic medium. Here I discuss recent advances in the development of numerical methods that introduce RT to cosmological hydrodynamics. These methods can also readily be applied to time dependent problems on interstellar and galactic scales.

  18. Thermostatic Radiator Valve Evaluation

    SciTech Connect (OSTI)

    Dentz, Jordan; Ansanelli, Eric

    2015-01-01

    A large stock of multifamily buildings in the Northeast and Midwest are heated by steam distribution systems. Losses from these systems are typically high and a significant number of apartments are overheated much of the time. Thermostatically controlled radiator valves (TRVs) are one potential strategy to combat this problem, but have not been widely accepted by the residential retrofit market.

  19. Local microwave background radiation

    E-Print Network [OSTI]

    Domingos Soares

    2014-11-13

    An inquiry on a possible local origin for the Microwave Background Radiation is made. Thermal MBR photons are contained in a system called {\\it magnetic bottle} which is due to Earth magnetic field and solar wind particles, mostly electrons. Observational tests are anticipated.

  20. Study of Electromagnetically Induced Transparency using long-lived Singlet States

    E-Print Network [OSTI]

    Soumya Singha Roy; T. S. Mahesh

    2011-03-17

    The long-lived singlet states are useful to study a variety of interesting quantum phenomena. In this work we study electromagnetically induced transparency using a two-qubit system. The singlet state acts as a `dark state' which does not absorb a probe radiation in the presence of a control radiation. Further we demonstrate that the simultaneous irradiation of probe and control radiations acts as a dynamical decoupling preserving the singlet state at higher correlation for longer durations.

  1. Radiation Chemistry Radiation causes changes in molecules by both

    E-Print Network [OSTI]

    Massey, Thomas N.

    Module 4 Radiation Chemistry Radiation causes changes in molecules by both direct and indirect radiation on the target molecules Indirect Action - energy transported by chemical species to cause damage or Pyrimidene. Loss of Purine or Pyrimidine Free radical transfer causing the loss of base and chain

  2. Radiation Safety Manual March 21, 2015 RADIATION SAFETY

    E-Print Network [OSTI]

    Lance, Veronica P.

    . Radioactive Drug Research Committee D. Radiation Safety Officers E. Authorized Users Chapter II: Radiation. Clinical Applications C. Loans and Transfers of Radioactive Materials Chapter VI: Occupational Exposure of Packages Containing Radioactive Materials A. Packages Delivered to the Radiation Safety Office B. Packages

  3. Radiation Safety Training Basic Radiation Safety Training for

    E-Print Network [OSTI]

    Dai, Pengcheng

    Radiation Safety Training Basic Radiation Safety Training for Sealed Source Users for Physics 461 Protocol Title: Training for Sealed Source Users Drafted By: Chris Millsaps, RSS Reviewers: ZB, TU, GS Purpose: To provide basic radiation safety training to the users of sealed sources located

  4. Cell, Vol. 90, 4353, July 11, 1997, Copyright 1997 by Cell Press A Small, Stable RNA Induced by Oxidative

    E-Print Network [OSTI]

    Mekalanos, John

    suggest that the oxyS RNA acts as a regulator thatintegrates adaptation to hydro- A Small RNA InducedCell, Vol. 90, 4353, July 11, 1997, Copyright 1997 by Cell Press A Small, Stable RNA Induced-Fischer, While unique functions have been discovered for a subset of the small RNA population, the roles of other

  5. Triptolide, an Inhibitor of the Human Heat Shock Response That Enhances Stress-induced Cell Death*S

    E-Print Network [OSTI]

    Morimoto, Richard

    Triptolide, an Inhibitor of the Human Heat Shock Response That Enhances Stress-induced Cell Death chaperones, inducible by heat shock and a variety of other stresses, have critical roles in protein homeostasis, balancing cell stress with adaptation, survival, and cell death mechanisms. In transformed cells

  6. The Sponge Pump: The Role of Current Induced Flow in the Design of the Sponge Body Plan

    E-Print Network [OSTI]

    Yahel, Gitai

    The Sponge Pump: The Role of Current Induced Flow in the Design of the Sponge Body Plan Sally P filtration have estimated the energetic cost of pumping to be ,1% of its total metabolism implying there is little adaptive value to reducing the cost of pumping by using ``passive'' flow induced by the ambient

  7. Chromatic Light Adaptation Measured using Functional Magnetic Resonance Imaging

    E-Print Network [OSTI]

    Wandell, Brian A.

    Chromatic Light Adaptation Measured using Functional Magnetic Resonance Imaging Alex R. Wade- nisms within cone photoreceptor classes. Key words: fMRI; light adaptation; cones; simulation; V1; Naka regulation is part of a process called light adaptation. Light adaptation is an important computational step

  8. Data Modelling for Analysis of Adaptive Changes in Fly Photoreceptors

    E-Print Network [OSTI]

    Juusola, Mikko

    describe accurately the observed adaptation process at each new level of changing light inputs. GeneralizedData Modelling for Analysis of Adaptive Changes in Fly Photoreceptors Uwe Friederich1,2 , Daniel://www.shef.ac.uk/acse Abstract. Adaptation is a hallmark of sensory processing. We studied neural adaptation in intracellular

  9. Adaptively Secure Coin-Flipping, Revisited Shafi Goldwasser1

    E-Print Network [OSTI]

    International Association for Cryptologic Research (IACR)

    in this setting. We then shed light on the connection between adaptive and strongly adaptive adversariesAdaptively Secure Coin-Flipping, Revisited Shafi Goldwasser1 , Yael Tauman Kalai2 , and Sunoo Park3' bits, can tolerate t(n) = O( n) even in the presence of adaptive corruptions, and they conjectured

  10. Skeletal Adaptations in Humans How are we anatomically different?

    E-Print Network [OSTI]

    posteriorly #12;Skeletal Adaptations in Humans Vertebral Column lumbar + cervical curvatures more

  11. Bubble Radiation Detection: Current and Future Capability

    SciTech Connect (OSTI)

    AJ Peurrung; RA Craig

    1999-11-15

    Despite a number of noteworthy achievements in other fields, superheated droplet detectors (SDDs) and bubble chambers (BCs) have not been used for nuclear nonproliferation and arms control. This report examines these two radiation-detection technologies in detail and answers the question of how they can be or should be ''adapted'' for use in national security applications. These technologies involve closely related approaches to radiation detection in which an energetic charged particle deposits sufficient energy to initiate the process of bubble nucleation in a superheated fluid. These detectors offer complete gamma-ray insensitivity when used to detect neutrons. They also provide controllable neutron-energy thresholds and excellent position resolution. SDDs are extraordinarily simple and inexpensive. BCs offer the promise of very high efficiency ({approximately}75%). A notable drawback for both technologies is temperature sensitivity. As a result of this problem, the temperature must be controlled whenever high accuracy is required, or harsh environmental conditions are encountered. The primary findings of this work are listed and briefly summarized below: (1) SDDs are ready to function as electronics-free neutron detectors on demand for arms-control applications. The elimination of electronics at the weapon's location greatly eases the negotiability of radiation-detection technologies in general. (2) As a result of their high efficiency and sharp energy threshold, current BCs are almost ready for use in the development of a next-generation active assay system. Development of an instrument based on appropriately safe materials is warranted. (3) Both kinds of bubble detectors are ready for use whenever very high gamma-ray fields must be confronted. Spent fuel MPC and A is a good example where this need presents itself. (4) Both kinds of bubble detectors have the potential to function as low-cost replacements for conventional neutron detectors such as {sup 3}He tubes. For SDDs, this requires finding some way to get boron into the detector. For BCs, this requires finding operating conditions permitting a high duty cycle.

  12. RADIATION DAMAGE OF GERMANIUM DETECTORS

    E-Print Network [OSTI]

    Pehl, Richard H.

    2011-01-01

    the high-energy proton damage than was the planar detector.as far as radiation damage is concerned. Unfortunately, some28-29, 1978 LBL-7967 RADIATION DAMAGE OF GERMANIUM DETECTORS

  13. TIME DOMAIN SIMULATIONS OF RADIATION

    E-Print Network [OSTI]

    ;Introduction Fan Noise Forward Radiation Fan Noise Aft Radiation Jet Noise (separate LES Code)Traditional CFD a 16-processor machine yourself : 8 dual-processor workstations 800 MHz Pentium III processors 1 GB RAM

  14. DOE Radiation Records Contacts List

    Broader source: Energy.gov [DOE]

    DOE radiation records contact list for individuals to obtain records of occupational exposure directly from a DOE site.

  15. Gamma radiation field intensity meter

    DOE Patents [OSTI]

    Thacker, L.H.

    1995-10-17

    A gamma radiation intensity meter measures dose rate of a radiation field. The gamma radiation intensity meter includes a tritium battery emitting beta rays generating a current which is essentially constant. Dose rate is correlated to an amount of movement of an electroscope element charged by the tritium battery. Ionizing radiation decreases the voltage at the element and causes movement. A bleed resistor is coupled between the electroscope support element or electrode and the ionization chamber wall electrode. 4 figs.

  16. Gamma radiation field intensity meter

    DOE Patents [OSTI]

    Thacker, L.H.

    1994-08-16

    A gamma radiation intensity meter measures dose rate of a radiation field. The gamma radiation intensity meter includes a tritium battery emitting beta rays generating a current which is essentially constant. Dose rate is correlated to an amount of movement of an electroscope element charged by the tritium battery. Ionizing radiation decreases the voltage at the element and causes movement. A bleed resistor is coupled between the electroscope support element or electrode and the ionization chamber wall electrode. 4 figs.

  17. Gamma radiation field intensity meter

    DOE Patents [OSTI]

    Thacker, Louis H. (Knoxville, TN)

    1995-01-01

    A gamma radiation intensity meter measures dose rate of a radiation field. The gamma radiation intensity meter includes a tritium battery emitting beta rays generating a current which is essentially constant. Dose rate is correlated to an amount of movement of an electroscope element charged by the tritium battery. Ionizing radiation decreases the voltage at the element and causes movement. A bleed resistor is coupled between the electroscope support element or electrode and the ionization chamber wall electrode.

  18. Gamma radiation field intensity meter

    DOE Patents [OSTI]

    Thacker, Louis H. (Knoxville, TN)

    1994-01-01

    A gamma radiation intensity meter measures dose rate of a radiation field. The gamma radiation intensity meter includes a tritium battery emitting beta rays generating a current which is essentially constant. Dose rate is correlated to an amount of movement of an electroscope element charged by the tritium battery. Ionizing radiation decreases the voltage at the element and causes movement. A bleed resistor is coupled between the electroscope support element or electrode and the ionization chamber wall electrode.

  19. COLUMBIA UNIVERSITY Radiation Safety Program

    E-Print Network [OSTI]

    Jia, Songtao

    and will be maintained in a separate file from personnel radiation dosimeter records. All workers are specifically

  20. Silencing of poly(ADP-ribose) glycohydrolase sensitizes lung cancer cells to radiation through the abrogation of DNA damage checkpoint

    SciTech Connect (OSTI)

    Nakadate, Yusuke; Department of Bioengineering, Graduate School of Engineering, Osaka City University, 3-3-138 Sugimoto, Sumiyoshi-ku, Osaka 558-8585 ; Kodera, Yasuo; Kitamura, Yuka; Tachibana, Taro; Tamura, Tomohide; Koizumi, Fumiaki

    2013-11-29

    Highlights: Radiosensitization by PARG silencing was observed in multiple lung cancer cells. PAR accumulation was enhanced by PARG silencing after DNA damage. Radiation-induced G2/M arrest and checkpoint activation were impaired by PARG siRNA. -- Abstract: Poly(ADP-ribose) glycohydrolase (PARG) is a major enzyme that plays a role in the degradation of poly(ADP-ribose) (PAR). PARG deficiency reportedly sensitizes cells to the effects of radiation. In lung cancer, however, it has not been fully elucidated. Here, we investigated whether PARG siRNA contributes to an increased radiosensitivity using 8 lung cancer cell lines. Among them, the silencing of PARG induced a radiosensitizing effect in 5 cell lines. Radiation-induced G2/M arrest was largely suppressed by PARG siRNA in PC-14 and A427 cells, which exhibited significantly enhanced radiosensitivity in response to PARG knockdown. On the other hand, a similar effect was not observed in H520 cells, which did not exhibit a radiosensitizing effect. Consistent with a cell cycle analysis, radiation-induced checkpoint signals were not well activated in the PC-14 and A427 cells when treated with PARG siRNA. These results suggest that the increased sensitivity to radiation induced by PARG knockdown occurs through the abrogation of radiation-induced G2/M arrest and checkpoint activation in lung cancer cells. Our findings indicate that PARG could be a potential target for lung cancer treatments when used in combination with radiotherapy.

  1. Working With Radiation For Research

    E-Print Network [OSTI]

    Jia, Songtao

    flight New York to LA 5 Moving from east coast to Denver for one year 50 Moving from frame house to brick with an ever-present background of radiation. Radiation & Life 1* *2 #12;3 Radiation is energy traveling with sufficiently energy to remove electrons from the atoms or molecules of the substances it passes through. Can

  2. Adaptive Plasticity and Plasticity as an Adaptation: A Selective Review of Plasticity in Animal Morphology and Life History

    E-Print Network [OSTI]

    Gotthard, Karl

    Adaptive Plasticity and Plasticity as an Adaptation: A Selective Review of Plasticity in Animal wide-ranging. All key REVIEW references should be cited. A summary is required. Adaptive plasticity and plasticity as an adaptation: a selective review of plasticity in animal morphology and life history Karl

  3. Carbon contamination and oxidation of Au surfaces under extreme ultraviolet radiation: An x-ray photoelectron spectroscopy study

    E-Print Network [OSTI]

    Harilal, S. S.

    Carbon contamination and oxidation of Au surfaces under extreme ultraviolet radiation: An x 2012) Extreme ultraviolet (EUV) radiation-induced carbon contamination and oxidation of Au surfaces modification during EUV exposure. XPS analysis showed that total carbon contamination (C 1s peak

  4. Adaptive method with intercessory feedback control for an intelligent agent

    DOE Patents [OSTI]

    Goldsmith, Steven Y.

    2004-06-22

    An adaptive architecture method with feedback control for an intelligent agent provides for adaptively integrating reflexive and deliberative responses to a stimulus according to a goal. An adaptive architecture method with feedback control for multiple intelligent agents provides for coordinating and adaptively integrating reflexive and deliberative responses to a stimulus according to a goal. Re-programming of the adaptive architecture is through a nexus which coordinates reflexive and deliberator components.

  5. Adaptive and Non-Adaptive Distribution Functions for DSA Melanie Smith

    E-Print Network [OSTI]

    Mailler, Roger

    Adaptive and Non-Adaptive Distribution Functions for DSA Melanie Smith University of Tulsa 800 S. Tucker Drive Tulsa, OK 74104 melanie@utulsa.edu Sandip Sen University of Tulsa 800 S. Tucker Drive Tulsa, OK 74104 sandip-sen@utulsa.edu Roger Mailler University of Tulsa 800 S. Tucker Drive Tulsa, OK 74104

  6. EOLSS ADAPTATIONS TO LIFE IN MARINE CAVES PAGE 1 ADAPTATIONS TO LIFE IN MARINE CAVES

    E-Print Network [OSTI]

    Iliffe, Thomas M.

    EOLSS ADAPTATIONS TO LIFE IN MARINE CAVES PAGE 1 ADAPTATIONS TO LIFE IN MARINE CAVES Thomas M. Iliffe, Department of Marine Biology, Texas A&M University at Galveston, USA Rene E. Bishop, Department of caves will result in their extinction. 1. Introduction 1.1 Definition of anchialine and marine caves

  7. Stress-induced changes in gene interactions in human cells

    E-Print Network [OSTI]

    Ives, Zachary G.

    Stress-induced changes in gene interactions in human cells Renuka R. Nayak1 , William E. Bernal2 environments by changing gene expression and gene interactions. To study how human cells response to stress, we endo- plasmic reticulum stress and exposure to ionizing radiation. We identified thousands of genes

  8. Mechanism of genotoxicity induced by targeted cytoplasmic irradiation

    E-Print Network [OSTI]

    Mechanism of genotoxicity induced by targeted cytoplasmic irradiation M Hong1,2 , A Xu1,3 , H Zhou1 irradiation should not be ignored in radiation risk estimation. Although targeted cytoplasmic irradiation has precision was used to study mechanisms involved in mediating the genotoxic effects in irradiated human

  9. rev December 2010 Radiation Safety Manual Section 9 Radiation Protection Procedures

    E-Print Network [OSTI]

    Sniadecki, Nathan J.

    rev December 2010 Radiation Safety Manual Section 9 Radiation Protection Procedures Page 9-1 Section 9 Radiation Protection Procedures Contents Section 9 9-1 Radiation Protection Procedures Protective Measures - External Radiation.....................................9-5 1. Time

  10. Parametric study of shock-induced transport and energization of relativistic electrons in the magnetosphere

    E-Print Network [OSTI]

    Li, Xinlin

    Parametric study of shock-induced transport and energization of relativistic electrons December 2005. [1] The sudden appearance of a new radiation belt consisting of electrons with energies shock-induced injections of electrons with energies above 10 MeV to equatorial distances within 2.5 RE

  11. Tracking electron-induced carbon contamination and cleaning of Ru surfaces by Auger electron spectroscopy

    E-Print Network [OSTI]

    Harilal, S. S.

    Tracking electron-induced carbon contamination and cleaning of Ru surfaces by Auger electron that the EUV radiation induced surface contamination is associated with: (1) direct photo-dissociation in which-ray photoelectron spectroscopy (XPS) is commonly used for estimating carbon contamination in mirrors.11 However

  12. Time dependent changes in extreme ultraviolet reflectivity of Ru mirrors from electron-induced surface chemistry

    E-Print Network [OSTI]

    Harilal, S. S.

    dissociation of residual hydrocarbons plays a dominant role in the presence of additional PEs, and thus reduces degradation.2 In fact, radiation induced carbon contamination and surface oxidation have been shown to drive that the adsorption and subsequent EUV-induced dissociation of water molecules on Ru surface affect mirror performance

  13. Radiation Effects in Nuclear Waste Materials

    SciTech Connect (OSTI)

    Weber, William J.

    2005-09-30

    The objective of this project is to develop a fundamental understanding of radiation effects in glasses and ceramics, as well as the influence of solid-state radiation effects on aqueous dissolution kinetics, which may impact the performance of nuclear waste forms and stabilized nuclear materials. This work provides the underpinning science to develop improved glass and ceramic waste forms for the immobilization and disposition of high-level tank waste, excess plutonium, plutonium residues and scrap, other actinides, and other nuclear waste streams. Furthermore, this work is developing develop predictive models for the performance of nuclear waste forms and stabilized nuclear materials. Thus, the research performed under this project has significant implications for the immobilization of High-Level Waste (HLW) and Nuclear Materials, two mission areas within the Office of Environmental Management (EM). With regard to the HLW mission, this research will lead to improved understanding of radiation-induced degradation mechanisms and their effects on dissolution kinetics, as well as development of predictive models for waste form performance. In the Nuclear Materials mission, this research will lead to improvements in the understanding of radiation effects on the chemical and structural properties of materials for the stabilization and long-term storage of plutonium, highly-enriched uranium, and other actinides. The research uses plutonium incorporation, ion-beam irradiation, and electron-beam irradiation to simulate the effects of alpha decay and beta decay on relevant glasses and ceramics. The research under this project has the potential to result in improved glass and ceramic materials for the stabilization and immobilization of high-level tank waste, plutonium residues and scraps, surplus weapons plutonium, highly-enriched uranium, other actinides, and other radioactive materials.

  14. Radiation Effects in Nuclear Waste Materials

    SciTech Connect (OSTI)

    Weber, William J.

    2005-06-01

    The objective of this project is to develop a fundamental understanding of radiation effects in glasses and ceramics, as well as the influence of solid-state radiation effects on aqueous dissolution kinetics, which may impact the performance of nuclear waste forms and stabilized nuclear materials. This work provides the underpinning science to develop improved glass and ceramic waste forms for the immobilization and disposition of high-level tank waste, excess plutonium, plutonium residues and scrap, other actinides, and other nuclear waste streams. Furthermore, this work is developing develop predictive models for the performance of nuclear waste forms and stabilized nuclear materials. Thus, the research performed under this project has significant implications for the immobilization of High-Level Waste (HLW) and Nuclear Materials, two mission areas within the Office of Environmental Management (EM). With regard to the HLW mission, this research will lead to improved understanding of radiation-induced degradation mechanisms and their effects on dissolution kinetics, as well as development of predictive models for waste form performance. In the Nuclear Materials mission, this research will lead to improvements in the understanding of radiation effects on the chemical and structural properties of materials for the stabilization and long-term storage of plutonium, highly-enriched uranium, and other actinides. The research uses plutonium incorporation, ion-beam irradiation, and electron-beam irradiation to simulate the effects of alpha decay and beta decay on relevant glasses and ceramics. The research under this project has the potential to result in improved glass and ceramic materials for the stabilization and immobilization of high-level tank waste, plutonium residues and scraps, surplus weapons plutonium, highly-enriched uranium, other actinides, and other radioactive materials.

  15. Multilayer radiation shield

    DOE Patents [OSTI]

    Urbahn, John Arthur (Saratoga Springs, NY); Laskaris, Evangelos Trifon (Niskayuna, NY)

    2009-06-16

    A power generation system including: a generator including a rotor including a superconductive rotor coil coupled to a rotatable shaft; a first prime mover drivingly coupled to the rotatable shaft; and a thermal radiation shield, partially surrounding the rotor coil, including at least a first sheet and a second sheet spaced apart from the first sheet by centripetal force produced by the rotatable shaft. A thermal radiation shield for a generator including a rotor including a super-conductive rotor coil including: a first sheet having at least one surface formed from a low emissivity material; and at least one additional sheet having at least one surface formed from a low emissivity material spaced apart from the first sheet by centripetal force produced by the rotatable shaft, wherein each successive sheet is an incrementally greater circumferential arc length and wherein the centripetal force shapes the sheets into a substantially catenary shape.

  16. Handheld CZT radiation detector

    DOE Patents [OSTI]

    Murray, William S.; Butterfield, Kenneth B.; Baird, William

    2004-08-24

    A handheld CZT radiation detector having a CZT gamma-ray sensor, a multichannel analyzer, a fuzzy-logic component, and a display component is disclosed. The CZT gamma-ray sensor may be a coplanar grid CZT gamma-ray sensor, which provides high-quality gamma-ray analysis at a wide range of operating temperatures. The multichannel analyzer categorizes pulses produce by the CZT gamma-ray sensor into channels (discrete energy levels), resulting in pulse height data. The fuzzy-logic component analyzes the pulse height data and produces a ranked listing of radioisotopes. The fuzzy-logic component is flexible and well-suited to in-field analysis of radioisotopes. The display component may be a personal data assistant, which provides a user-friendly method of interacting with the detector. In addition, the radiation detector may be equipped with a neutron sensor to provide an enhanced mechanism of sensing radioactive materials.

  17. Semiconductor radiation detector

    DOE Patents [OSTI]

    Patt, Bradley E. (Sherman Oaks, CA); Iwanczyk, Jan S. (Los Angeles, CA); Tull, Carolyn R. (Orinda, CA); Vilkelis, Gintas (Westlake Village, CA)

    2002-01-01

    A semiconductor radiation detector is provided to detect x-ray and light photons. The entrance electrode is segmented by using variable doping concentrations. Further, the entrance electrode is physically segmented by inserting n+ regions between p+ regions. The p+ regions and the n+ regions are individually biased. The detector elements can be used in an array, and the p+ regions and the n+ regions can be biased by applying potential at a single point. The back side of the semiconductor radiation detector has an n+ anode for collecting created charges and a number of p+ cathodes. Biased n+ inserts can be placed between the p+ cathodes, and an internal resistor divider can be used to bias the n+ inserts as well as the p+ cathodes. A polysilicon spiral guard can be implemented surrounding the active area of the entrance electrode or surrounding an array of entrance electrodes.

  18. General Relativistic Radiative Transfer

    E-Print Network [OSTI]

    S. Knop; P. H. Hauschildt; E. Baron

    2006-11-30

    We present a general method to calculate radiative transfer including scattering in the continuum as well as in lines in spherically symmetric systems that are influenced by the effects of general relativity (GR). We utilize a comoving wavelength ansatz that allows to resolve spectral lines throughout the atmosphere. The used numerical solution is an operator splitting (OS) technique that uses a characteristic formal solution. The bending of photon paths and the wavelength shifts due to the effects of GR are fully taken into account, as is the treatment of image generation in a curved spacetime. We describe the algorithm we use and demonstrate the effects of GR on the radiative transport of a two level atom line in a neutron star like atmosphere for various combinations of continuous and line scattering coefficients. In addition, we present grey continuum models and discuss the effects of different scattering albedos on the emergent spectra and the determination of effective temperatures and radii of neutron star atmospheres.

  19. Radiation shielding composition

    DOE Patents [OSTI]

    Quapp, William J. (Idaho Falls, ID); Lessing, Paul A. (Idaho Falls, ID)

    2000-12-26

    A composition for use as a radiation shield. The shield is a concrete product containing a stable uranium aggregate for attenuating gamma rays and a neutron absorbing component, the uranium aggregate and neutron absorbing component being present in the concrete product in sufficient amounts to provide a concrete having a density between about 4 and about 15 grams/cm.sup.3 and which will at a predetermined thickness, attenuate gamma rays and absorb neutrons from a radioactive material of projected gamma ray and neutron emissions over a determined time period. The composition is preferably in the form of a container for storing radioactive materials that emit gamma rays and neutrons. The concrete container preferably comprises a metal liner and/or a metal outer shell. The resulting radiation shielding container has the potential of being structurally sound, stable over a long period of time, and, if desired, readily mobile.

  20. Radiation shielding composition

    DOE Patents [OSTI]

    Quapp, William J. (Idaho Falls, ID); Lessing, Paul A. (Idaho Falls, ID)

    1998-01-01

    A composition for use as a radiation shield. The shield is a concrete product containing a stable uranium aggregate for attenuating gamma rays and a neutron absorbing component, the uranium aggregate and neutron absorbing component being present in the concrete product in sufficient amounts to provide a concrete having a density between about 4 and about 15 grams/cm.sup.3 and which will at a predetermined thickness, attenuate gamma rays and absorb neutrons from a radioactive material of projected gamma ray and neutron emissions over a determined time period. The composition is preferably in the form of a container for storing radioactive materials that emit gamma rays and neutrons. The concrete container preferably comprises a metal liner and/or a metal outer shell. The resulting radiation shielding container has the potential of being structurally sound, stable over a long period of time, and, if desired, readily mobile.