National Library of Energy BETA

Sample records for beta-gamma dose rates

  1. Beta-gamma discriminator circuit

    SciTech Connect (OSTI)

    Erkkila, B.H.; Wolf, M.A.; Eisen, Y.; Unruh, W.P.; Brake, R.J.

    1984-01-01

    The major difficulty encountered in the determination of beta-ray dose in field conditions is generally the presence of a relatively high gamma-ray component. Conventional dosimetry instruments use a shield on the detector to estimate the gamma-ray component in comparison with the beta-ray component. More accurate dosimetry information can be obtained from the measured beta spectrum itself. At Los Alamos, a detector and discriminator circuit suitable for use in a portable spectrometer have been developed. This instrument will discriminate between gammas and betas in a mixed field. The portable package includes a 256-channel MCA which can be programmed to give a variety of outputs, including a spectral display, and may be programmed to read dose directly.

  2. 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.

  3. Extended range radiation dose-rate monitor

    DOE Patents [OSTI]

    Valentine, Kenneth H. (Knoxville, TN)

    1988-01-01

    An extended range dose-rate monitor is provided which utilizes the pulse pileup phenomenon that occurs in conventional counting systems to alter the dynamic response of the system to extend the dose-rate counting range. The current pulses from a solid-state detector generated by radiation events are amplified and shaped prior to applying the pulses to the input of a comparator. The comparator generates one logic pulse for each input pulse which exceeds the comparator reference threshold. These pulses are integrated and applied to a meter calibrated to indicate the measured dose-rate in response to the integrator output. A portion of the output signal from the integrator is fed back to vary the comparator reference threshold in proportion to the output count rate to extend the sensitive dynamic detection range by delaying the asymptotic approach of the integrator output toward full scale as measured by the meter.

  4. Radiation dose rates from UF{sub 6} cylinders

    SciTech Connect (OSTI)

    Friend, P.J.

    1991-12-31

    This paper describes the results of many studies, both theoretical and experimental, which have been carried out by Urenco over the last 15 years into radiation dose rates from uranium hexafluoride (UF{sub 6}) cylinders. The contents of the cylinder, its history, and the geometry all affect the radiation dose rate. These factors are all examined in detail. Actual and predicted dose rates are compared with levels permitted by IAEA transport regulations.

  5. Dose Rate Calculations for Rotary Mode Core Sampling Exhauster

    SciTech Connect (OSTI)

    FOUST, D.J.

    2000-10-26

    This document provides the calculated estimated dose rates for three external locations on the Rotary Mode Core Sampling (RMCS) exhauster HEPA filter housing, per the request of Characterization Field Engineering.

  6. PRECEDENTS FOR AUTHORIZATION OF CONTENTS USING DOSE RATE MEASUREMENTS

    SciTech Connect (OSTI)

    Abramczyk, G.; Bellamy, S.; Nathan, S.; Loftin, B.

    2012-06-05

    For the transportation of Radioactive Material (RAM) packages, the requirements for the maximum allowed dose rate at the package surface and in its vicinity are given in Title 10 of the Code of Federal Regulations, Section 71.47. The regulations are based on the acceptable dose rates to which the public, workers, and the environment may be exposed. As such, the regulations specify dose rates, rather than quantity of radioactive isotopes and require monitoring to confirm the requirements are met. 10CFR71.47 requires that each package of radioactive materials offered for transportation must be designed and prepared for shipment so that under conditions normally incident to transportation the radiation level does not exceed 2 mSv/h (200 mrem/h) at any point on the external Surface of the package, and the transport index does not exceed 10. Before shipment, the dose rate of the package is determined by measurement, ensuring that it conforms to the regulatory limits, regardless of any analyses. This is the requirement for all certified packagings. This paper discusses the requirements for establishing the dose rates when shipping RAM packages and the precedents for meeting these requirements by measurement.

  7. ACDOS2: an improved neutron-induced dose rate code

    SciTech Connect (OSTI)

    Lagache, J.C.

    1981-06-01

    To calculate the expected dose rate from fusion reactors as a function of geometry, composition, and time after shutdown a computer code, ACDOS2, was written, which utilizes up-to-date libraries of cross-sections and radioisotope decay data. ACDOS2 is in ANSI FORTRAN IV, in order to make it readily adaptable elsewhere.

  8. Total dose and dose rate models for bipolar transistors in circuit simulation.

    SciTech Connect (OSTI)

    Campbell, Phillip Montgomery; Wix, Steven D.

    2013-05-01

    The objective of this work is to develop a model for total dose effects in bipolar junction transistors for use in circuit simulation. The components of the model are an electrical model of device performance that includes the effects of trapped charge on device behavior, and a model that calculates the trapped charge densities in a specific device structure as a function of radiation dose and dose rate. Simulations based on this model are found to agree well with measurements on a number of devices for which data are available.

  9. High dose rate intraluminal irradiation in recurrent endobronchial carcinoma

    SciTech Connect (OSTI)

    Seagren, S.L.; Harrell, J.H.; Horn, R.A.

    1985-12-01

    Palliative therapy for previously irradiated patients with symptomatic recurrent endobronchial malignancy is a difficult problem. We have had the opportunity to treat 20 such patients with high dose rate (50-100 rad/min) endobronchial brachytherapy. Eligible patients had received previous high dose thoracic irradiation (TDF greater than or equal to 90), a performance status of greater than or equal to 50, and symptoms caused by a bronchoscopically defined and implantable lesion. The radiation is produced by a small cobalt-60 source (0.7 Ci) remotely afterloaded by cable control. The source is fed into a 4 mm diameter catheter which is placed with bronchoscopic guidance; it may oscillate if necessary to cover the lesion. A dose of 1,000 rad at 1 cm from the source is delivered. We have performed 22 procedures in 20 patients, four following YAG laser debulking. Most had cough, some with hemoptysis. Eight had dyspnea secondary to obstruction and three had obstructive pneumonitis. In 12, symptoms recurred with a mean time to recurrence of 4.3 months (range 1-9 months). Eighteen patients were followed-up and reexamined via bronchoscope 1-2.5 months following the procedure; two were lost to follow-up. All had at least 50 percent clearance of tumor, and six had complete clearance; most regressions were documented on film or videotape. In six, the palliation was durable. The procedure has been well tolerated with no toxicity. We conclude that palliative endobronchial high dose rate brachytherapy is a useful palliative modality in patients with recurrent endobronchial symptomatic carcinoma.

  10. Radiation dose-rate meter using an energy-sensitive counter

    DOE Patents [OSTI]

    Kopp, Manfred K. (Oak Ridge, TN)

    1988-01-01

    A radiation dose-rate meter is provided which uses an energy-sensitive detector and combines charge quantization and pulse-rate measurement to monitor radiation dose rates. The charge from each detected photon is quantized by level-sensitive comparators so that the resulting total output pulse rate is proportional to the dose-rate.

  11. The susceptibility of TaOx-based memristors to high dose rate ionizing radiation and total ionizing dose

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

    McLain, Michael Lee; Sheridan, Timothy J.; Hjalmarson, Harold Paul; Mickel, Patrick R.; Hanson, Donald J.; McDonald, Joseph K.; Hughart, David Russell; Marinella, Matthew J.

    2014-11-11

    This paper investigates the effects of high dose rate ionizing radiation and total ionizing dose (TID) on tantalum oxide (TaOx) memristors. Transient data were obtained during the pulsed exposures for dose rates ranging from approximately 5.0 ×107 rad(Si)/s to 4.7 ×108 rad(Si)/s and for pulse widths ranging from 50 ns to 50 μs. The cumulative dose in these tests did not appear to impact the observed dose rate response. Static dose rate upset tests were also performed at a dose rate of ~3.0 ×108 rad(Si)/s. This is the first dose rate study on any type of memristive memory technology. Inmore » addition to assessing the tolerance of TaOx memristors to high dose rate ionizing radiation, we also evaluated their susceptibility to TID. The data indicate that it is possible for the devices to switch from a high resistance off-state to a low resistance on-state in both dose rate and TID environments. The observed radiation-induced switching is dependent on the irradiation conditions and bias configuration. Furthermore, the dose rate or ionizing dose level at which a device switches resistance states varies from device to device; the enhanced susceptibility observed in some devices is still under investigation. As a result, numerical simulations are used to qualitatively capture the observed transient radiation response and provide insight into the physics of the induced current/voltages.« less

  12. Genetic Factors Affecting Susceptibility to Low Dose & Low Dose-Rate Radiation

    SciTech Connect (OSTI)

    Bedford, Joel

    2014-04-18

    Our laboratory has, among other things, developed and used the gamma H2AX focus assay and other chromosomal and cell killing assays to show that differences in this DNA double strand break (dsb) related response can be clearly and distinctly demonstrated for cells which are mildly hyper-radiosensitive such as those associated with A-T heterozygosity. We have found this level of mild hypersensitivity for cells from some 20 to 30 % of apparently normal individuals and from apparently normal parents of Retinoblastoma patients. We found significant differences in gene expression in somatic cells from unaffected parents of Rb patients as compared with normal controls, suggesting that these parents may harbor some as yet unidentified genetic abnormality. In other experiments we sought to determine the extent of differences in normal human cellular reaponses to radiation depending on their irradiation in 2D monolayer vs 3D organized acinar growth conditions. We exmined cell reproductive death, chromosomal aberration induction, and the levels of ?-H2AX foci in cells after single acute gamma-ray doses and immediately after 20 hours of irradiation at a dose rate of 0.0017 Gy/min. We found no significant differences in the dose-responses of these cells under the 2D or 3D growth conditions. While this does not mean such differences cannot occur in other situations, it does mean that they do not generally or necessarily occur. In another series of studies in collaboration with Dr Chuan Li, with supprt from this current grant. We reported a role for apoptotic cell death in promoting wound healing and tissue regeneration in mice. Apoptotic cells released growth signals that stimulated the proliferation of progenitor or stem cells. In yet another collaboration with Dr, B. Chen with funds from this grant, the relative radiosensitivity to cell killing as well as chromosomal instability of 13 DNA-PKcs site-directed mutant cell lines (defective at phosphorylation sites or kinase activity) were examined after exposure of synchronized G1 cells to 137Cs c rays. DNA-PKcs mutant cells defective in phosphorylation at multiple sites withinthe T2609 cluster or within the PI3K domain displayed extreme radiosensitivity. Cells defective at the S2056 cluster or T2609 single site alone were only mildly radiosensitive, but cells defective at even one site in both the S2056 and T2609 clusters were maximally radiosensitive. Thus a synergism between the capacity for phosphorylation at the S2056 and T2609 clusterswas found to be critical for induction of radiosensitivity.

  13. 'In vivo' Dose Measurements in High-Dose-Rate Brachytherapy Treatments for Cervical Cancer: A Project Proposal

    SciTech Connect (OSTI)

    Reynoso Mejia, C. A.; Buenfil Burgos, A. E.; Ruiz Trejo, C.; Mota Garcia, A.; Trejo Duran, E.; Rodriguez Ponce, M.; Gamboa de Buen, I.

    2010-12-07

    The aim of this thesis project is to compare doses calculated from the treatment planning system using computed tomography images, with those measured 'in vivo' by using thermoluminescent dosimeters placed at different regions of the rectum and bladder of a patient during high-dose-rate intracavitary brachytherapy treatment of uterine cervical carcinoma. The experimental dosimeters characterisation and calibration have concluded and the protocol to carry out the 'in vivo' measurements has been established. In this work, the calibration curves of two types of thermoluminescent dosimeters (rods and chips) are presented, and the proposed protocol to measure the 'in vivo' dose is fully described.

  14. HDRMC, an accelerated Monte Carlo dose calculator for high dose rate brachytherapy with CT-compatible applicators

    SciTech Connect (OSTI)

    Chibani, Omar C-M Ma, Charlie

    2014-05-15

    Purpose: To present a new accelerated Monte Carlo code for CT-based dose calculations in high dose rate (HDR) brachytherapy. The new code (HDRMC) accounts for both tissue and nontissue heterogeneities (applicator and contrast medium). Methods: HDRMC uses a fast ray-tracing technique and detailed physics algorithms to transport photons through a 3D mesh of voxels representing the patient anatomy with applicator and contrast medium included. A precalculated phase space file for the{sup 192}Ir source is used as source term. HDRM is calibrated to calculated absolute dose for real plans. A postprocessing technique is used to include the exact density and composition of nontissue heterogeneities in the 3D phantom. Dwell positions and angular orientations of the source are reconstructed using data from the treatment planning system (TPS). Structure contours are also imported from the TPS to recalculate dose-volume histograms. Results: HDRMC was first benchmarked against the MCNP5 code for a single source in homogenous water and for a loaded gynecologic applicator in water. The accuracy of the voxel-based applicator model used in HDRMC was also verified by comparing 3D dose distributions and dose-volume parameters obtained using 1-mm{sup 3} versus 2-mm{sup 3} phantom resolutions. HDRMC can calculate the 3D dose distribution for a typical HDR cervix case with 2-mm resolution in 5 min on a single CPU. Examples of heterogeneity effects for two clinical cases (cervix and esophagus) were demonstrated using HDRMC. The neglect of tissue heterogeneity for the esophageal case leads to the overestimate of CTV D90, CTV D100, and spinal cord maximum dose by 3.2%, 3.9%, and 3.6%, respectively. Conclusions: A fast Monte Carlo code for CT-based dose calculations which does not require a prebuilt applicator model is developed for those HDR brachytherapy treatments that use CT-compatible applicators. Tissue and nontissue heterogeneities should be taken into account in modern HDR brachytherapy planning.

  15. Multi-level effects of low dose rate ionizing radiation on southern toad, Anaxyrus [Bufo] terrestris

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

    Stark, Karolina; Scott, David E.; Tsyusko, Olga; Coughlin, Daniel P.; Hinton, Thomas G.; Amendola, Roberto

    2015-04-30

    Despite their potential vulnerability to contaminants from exposure at multiple life stages, amphibians are one of the least studied groups of vertebrates in ecotoxicology, and research on radiation effects in amphibians is scarce. We used multiple endpoints to assess the radiosensitivity of the southern toad (Anaxyrus [Bufo] terrestris) during its pre-terrestrial stages of development –embryonic, larval, and metamorphic. Toads were exposed, from several hours after oviposition through metamorphosis (up to 77 days later), to four low dose rates of ¹³⁷Cs at 0.13, 2.4, 21, and 222 mGy d⁻¹, resulting in total doses up to 15.8 Gy. Radiation treatments did notmore » affect hatching success of embryos, larval survival, or the length of the larval period. The individual family variation in hatching success of embryos was larger than the radiation response. In contrast, newly metamorphosed individuals from the higher dose-rate treatments had higher mass and mass/length body indices, a measure which may relate to higher post-metamorphic survival. The increased mass and index at higher dose rates may indicate that the chronic, low dose rate radiation exposures triggered secondary responses. Additionally, the increases in growth were linked to a decrease in DNA damage (as measured by the Comet Assay) in red blood cells at a dose rate of 21mGy d⁻¹ and a total dose of 1.1 Gy. In conclusion, the complex effects of low dose rates of ionizing radiation may trigger growth and cellular repair mechanisms in amphibian larvae.« less

  16. Radiation bronchitis and stenosis secondary to high dose rate endobronchial irradiation

    SciTech Connect (OSTI)

    Speiser, B.L. ); Spratling, L.

    1993-03-15

    The purpose of the study was to describe a new clinical entity observed in follow-up bronchoscopies in patients who were treated with high dose rate and medium dose rate remote afterloading brachytherapy of the tracheobronchial tree. Patients were treated by protocol with medium dose rate, 47 patients receiving 1000 cGy at a 5 mm depth times three fractions, high dose rate 144 patients receiving 1000 cGy at a 10 mm depth for three fractions and high dose rate 151 patients receiving cGy at a 10 mm depth for three fractions followed by bronchoscopy. Incidence of this entity was 9% for the first group, 12% for the second, and 13% for the third group. Reactions were grade 1 consisting of mild inflammatory response with a partial whitish circumferential membrane in an asymptomatic patient; grade 2, thicker complete white circumferential membrane with cough and/or obstructive problems requiring intervention; grade 3, severe inflammatory response with marked membranous exudate and mild fibrotic reaction; and grade 4 a predominant fibrotic reaction with progressive stenosis. Variables associated with a slightly increased incidence of radiation bronchitis and stenosis included: large cell carcinoma histology, curative intent, prior laser photoresection, and/or concurrent external radiation. Survival was the strongest predictor of the reaction. Radiation bronchitis and stenosis is a new clinical entity that must be identified in bronchial brachytherapy patients and treated appropriately. 23 refs., 3 figs., 7 tabs.

  17. Dose Rate Analysis Capability for Actual Spent Fuel Transportation Cask Contents

    SciTech Connect (OSTI)

    Radulescu, Georgeta; Lefebvre, Robert A; Peplow, Douglas E.; Williams, Mark L; Scaglione, John M

    2014-01-01

    The approved contents for a U.S. Nuclear Regulatory Commission (NRC) licensed spent nuclear fuel casks are typically based on bounding used nuclear fuel (UNF) characteristics. However, the contents of the UNF canisters currently in storage at independent spent fuel storage installations are considerably heterogeneous in terms of fuel assembly burnup, initial enrichment, decay time, cladding integrity, etc. Used Nuclear Fuel Storage, Transportation & Disposal Analysis Resource and Data System (UNF ST&DARDS) is an integrated data and analysis system that facilitates automated cask-specific safety analyses based on actual characteristics of the as-loaded UNF. The UNF-ST&DARDS analysis capabilities have been recently expanded to include dose rate analysis of as-loaded transportation packages. Realistic dose rate values based on actual canister contents may be used in place of bounding dose rate values to support development of repackaging operations procedures, evaluation of radiation-related transportation risks, and communication with stakeholders. This paper describes the UNF-ST&DARDS dose rate analysis methodology based on actual UNF canister contents and presents sample dose rate calculation results.

  18. Measured dose rate constant from oncology patients administered 18F for positron emission tomography

    SciTech Connect (OSTI)

    Quinn, Brian; Holahan, Brian; Aime, Jean; Humm, John; St Germain, Jean; Dauer, Lawrence T.

    2012-10-15

    Purpose: Patient exposure rate measurements verify published patient dose rate data and characterize dose rates near 2-18-fluorodeoxyglucose ({sup 18}F-FDG) patients. A specific dose rate constant based on patient exposure rate measurements is a convenient quantity that can be applied to the desired distance, injection activity, and time postinjection to obtain an accurate calculation of cumulative external radiation dose. This study reports exposure rates measured at various locations near positron emission tomography (PET) {sup 18}F-FDG patients prior to PET scanning. These measurements are normalized for the amount of administered activity, measurement distance, and time postinjection and are compared with other published data. Methods: Exposure rates were measured using a calibrated ionization chamber at various body locations from 152 adult oncology patients postvoid after a mean uptake time of 76 min following injection with a mean activity of 490 MBq {sup 18}F-FDG. Data were obtained at nine measurement locations for each patient: three near the head, four near the chest, and two near the feet. Results: On contact with, 30 cm superior to and 30 cm lateral to the head, the mean (75th percentile) dose rates per unit injected activity at 60 min postinjection were 0.482 (0.511), 0.135 (0.155), and 0.193 (0.223) {mu}Sv/MBq h, respectively. On contact with, 30 cm anterior to, 30 cm lateral to and 1 m anterior to the chest, the mean (75th percentile) dose rates per unit injected activity at 60 min postinjection were 0.623 (0.709), 0.254 (0.283), 0.190 (0.218), and 0.067 (0.081) {mu}Sv/MBq h respectively. 30 cm inferior and 30 cm lateral to the feet, the mean (75th percentile) dose rates per unit injected activity at 60 min postinjection were 0.024 (0.022) and 0.039 (0.044) {mu}Sv/MBq h, respectively. Conclusions: The measurements for this study support the use of 0.092 {mu}Sv m{sup 2}/MBq h as a reasonable representation of the dose rate anterior from the chest of patients immediately following injection. This value can then be reliably scaled to the desired time and distance for planning and staff dose evaluation purposes. At distances closer than 1 m, a distance-specific dose rate constant of 0.367 {mu}Sv/MBq h at 30 cm is recommended for accurate calculations. An accurate patient-specific dose rate constant that accounts for patient-specific variables (e.g., distribution and attenuation) will allow an accurate evaluation of the dose rate from a patient injected with an isotope rather than simply utilizing a physical constant.

  19. ITER Generic Diagnostic Upper Port Plug Nuclear Heating and Personnel Dose Rate Assesment

    SciTech Connect (OSTI)

    Russell E. Feder and Mahmoud Z. Youssef

    2009-01-28

    Neutronics analysis to find nuclear heating rates and personnel dose rates were conducted in support of the integration of diagnostics in to the ITER Upper Port Plugs. Simplified shielding models of the Visible-Infrared diagnostic and of a large aperture diagnostic were incorporated in to the ITER global CAD model. Results for these systems are representative of typical designs with maximum shielding and a small aperture (Vis-IR) and minimal shielding with a large aperture. The neutronics discrete-ordinates code ATTILA and SEVERIAN (the ATTILA parallel processing version) was used. Material properties and the 500 MW D-T volume source were taken from the ITER Brand Model MCNP benchmark model. A biased quadrature set equivelant to Sn=32 and a scattering degree of Pn=3 were used along with a 46-neutron and 21-gamma FENDL energy subgrouping. Total nuclear heating (neutron plug gamma heating) in the upper port plugs ranged between 380 and 350 kW for the Vis-IR and Large Aperture cases. The Large Aperture model exhibited lower total heating but much higher peak volumetric heating on the upper port plug structure. Personnel dose rates are calculated in a three step process involving a neutron-only transport calculation, the generation of activation volume sources at pre-defined time steps and finally gamma transport analyses are run for selected time steps. ANSI-ANS 6.1.1 1977 Flux-to-Dose conversion factors were used. Dose rates were evaluated for 1 full year of 500 MW DT operation which is comprised of 3000 1800-second pulses. After one year the machine is shut down for maintenance and personnel are permitted to access the diagnostic interspace after 2-weeks if dose rates are below 100 ?Sv/hr. Dose rates in the Visible-IR diagnostic model after one day of shutdown were 130 ?Sv/hr but fell below the limit to 90 ?Sv/hr 2-weeks later. The Large Aperture style shielding model exhibited higher and more persistent dose rates. After 1-day the dose rate was 230 ?Sv/hr but was still at 120 ?Sv/hr 4-weeks later.

  20. Iron Oxide Nanoparticle Agglomeration Influences Dose-Rates and Modulates Oxidative Stress Mediated Dose-Response Profiles In Vitro

    SciTech Connect (OSTI)

    Sharma, Gaurav; Kodali, Vamsi K.; Gaffrey, Matthew J.; Wang, Wei; Minard, Kevin R.; Karin, Norman J.; Teeguarden, Justin G.; Thrall, Brian D.

    2013-07-31

    Spontaneous agglomeration of engineered nanoparticles (ENPs) is a common problem in cell culture media which can confound interpretation of in vitro nanotoxicity studies. The authors created stable agglomerates of iron oxide nanoparticles (IONPs) in conventional culture medium, which varied in hydrodynamic size (276 nm-1.5 ?m) but were composed of identical primary particles with similar surface potentials and protein coatings. Studies using C10 lung epithelial cells show that the dose rate effects of agglomeration can be substantial, varying by over an order of magnitude difference in cellular dose in some cases. Quantification by magnetic particle detection showed that small agglomerates of carboxylated IONPs induced greater cytotoxicity and redox-regulated gene expression when compared with large agglomerates on an equivalent total cellular IONP mass dose basis, whereas agglomerates of amine-modified IONPs failed to induce cytotoxicity or redox-regulated gene expression despite delivery of similar cellular doses. Dosimetry modelling and experimental measurements reveal that on a delivered surface area basis, large and small agglomerates of carboxylated IONPs have similar inherent potency for the generation of ROS, induction of stress-related genes and eventual cytotoxicity. The results suggest that reactive moieties on the agglomerate surface are more efficient in catalysing cellular ROS production than molecules buried within the agglomerate core. Because of the dynamic, size and density-dependent nature of ENP delivery to cells in vitro, the biological consequences of agglomeration are not discernible from static measures of exposure concentration (?g/ml) alone, highlighting the central importance of integrated physical characterisation and quantitative dosimetry for in vitro studies. The combined experimental and computational approach provides a quantitative framework for evaluating relationships between the biocompatibility of nanoparticles and their physical and chemical characteristics.

  1. Feasibility study of volumetric modulated arc therapy with constant dose rate for endometrial cancer

    SciTech Connect (OSTI)

    Yang, Ruijie; Wang, Junjie; Xu, Feng; Li, Hua; Zhang, Xile

    2013-10-01

    To investigate the feasibility, efficiency, and delivery accuracy of volumetric modulated arc therapy with constant dose rate (VMAT-CDR) for whole-pelvic radiotherapy (WPRT) of endometrial cancer. The nine-field intensity-modulated radiotherapy (IMRT), VMAT with variable dose-rate (VMAT-VDR), and VMAT-CDR plans were created for 9 patients with endometrial cancer undergoing WPRT. The dose distribution of planning target volume (PTV), organs at risk (OARs), and normal tissue (NT) were compared. The monitor units (MUs) and treatment delivery time were also evaluated. For each VMAT-CDR plan, a dry run was performed to assess the dosimetric accuracy with MatriXX from IBA. Compared with IMRT, the VMAT-CDR plans delivered a slightly greater V{sub 20} of the bowel, bladder, pelvis bone, and NT, but significantly decreased the dose to the high-dose region of the rectum and pelvis bone. The MUs decreased from 1105 with IMRT to 628 with VMAT-CDR. The delivery time also decreased from 9.5 to 3.2 minutes. The average gamma pass rate was 95.6% at the 3%/3 mm criteria with MatriXX pretreatment verification for 9 patients. VMAT-CDR can achieve comparable plan quality with significant shorter delivery time and smaller number of MUs compared with IMRT for patients with endometrial cancer undergoing WPRT. It can be accurately delivered and be an alternative to IMRT on the linear accelerator without VDR capability.

  2. Is the Use of a Surrogate Urethra an Option in Prostate High-Dose-Rate Brachytherapy?

    SciTech Connect (OSTI)

    Nilsson, Josef Kaelkner, Karl Mikael; Berg, Lars; Levitt, Seymour; Holmberg, Carina; Nilsson, Sten; Lundell, Marie

    2008-05-01

    Purpose: To investigate the accuracy and the dosimetric consequences of substituting a surrogate urethra assumed to be at the geometric center of the prostate, in place of the true urethra when using high-dose-rate (HDR) brachytherapy for the treatment of prostate cancer. Methods and Materials: One hundred prostate cancer patients treated with HDR brachytherapy constituted the study group. A pre-plan was made with the urethra visualized. The true urethra was defined, and a surrogate urethra was placed at the geometric center of the prostate. The distance between the two urethras was measured. The deviation was evaluated at the base, middle, and apex. To evaluate the dosimetric consequences for the true urethra when using a surrogate urethra, two different dose plans were made: one based on the true urethra and one based on the surrogate urethra. The dose-volume histograms for the true urethra were analyzed. Results: The deviation between the true urethra and the surrogate urethra was greatest at the base of the prostate. A statistically significant difference was seen between the dosimetric parameters for the true and the surrogate urethra when the dose plan was made using the surrogate urethra. In this situation the dose to the true urethra was increased above our defined maximum tolerance limit. Conclusions: When using dose plans made according to a surrogate urethra the dose to the true urethra might be too high to be acceptable. If the true urethra is not visualized, severe damage could easily develop in a significant number of patients.

  3. Absorbed dose rates in tissue from prompt gamma emissions from near-thermal neutron absorption

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

    Schwahn, Scott O.

    2015-10-01

    Prompt gamma emission data from the International Atomic Energy Agency s Prompt Gamma-ray Neutron Activation Analysis database are analyzed to determine the absorbed dose rates in tissue to be expected when natural elements are exposed in a near-thermal neutron environment.

  4. In vivo real-time dosimetric verification in high dose rate prostate brachytherapy

    SciTech Connect (OSTI)

    Seymour, Erin L.; Downes, Simon J.; Fogarty, Gerald B.; Izard, Michael A.; Metcalfe, Peter

    2011-08-15

    Purpose: To evaluate the performance of a diode array in the routine verification of planned dose to points inside the rectum from prostate high dose rate (HDR) brachytherapy using a real-time planning system. Methods: A dosimetric study involving 28 patients was undertaken where measured doses received during treatment were compared to those calculated by the treatment planning system (TPS). After the ultrasound imaging required for treatment planning had been recorded, the ultrasound probe was replaced with a geometric replica that contained an 8 mm diameter cylindrical cavity in which a PTW diode array type 9112 was placed. The replica probe was then positioned inside the rectum with the individual diode positions determined using fluoroscopy. Dose was then recorded during the patients' treatment and compared to associated coordinates in the planning system. Results: Factors influencing diode response and experimental uncertainty were initially investigated to estimate the overall uncertainty involved in dose measurements, which was determined to be {+-}10%. Data was acquired for 28 patients' first fractions, 11 patients' second fractions, and 13 patients' third fractions with collection dependent upon circumstances. Deviations between the diode measurements and predicted values ranged from -42% to +35% with 71% of measurements experiencing less than a 10% deviation from the predicted values. If the {+-}10% measurement uncertainty was combined with a tolerated dose discrepancy of {+-}10% then over 95% of the diode results exhibited agreement with the calculated data to within {+-}20%. It must also be noted that when large dose discrepancies were apparent they did not necessarily occur for all five diodes in the one measurement. Conclusions: This technique provided a method that could be utilized to detect gross errors in dose delivery of a real-time prostate HDR plan. Limitations in the detection system used must be well understood if meaningful results are to be achieved.

  5. Method to determine the position-dependant metal correction factor for dose-rate equivalent laser testing of semiconductor devices

    DOE Patents [OSTI]

    Horn, Kevin M.

    2013-07-09

    A method reconstructs the charge collection from regions beneath opaque metallization of a semiconductor device, as determined from focused laser charge collection response images, and thereby derives a dose-rate dependent correction factor for subsequent broad-area, dose-rate equivalent, laser measurements. The position- and dose-rate dependencies of the charge-collection magnitude of the device are determined empirically and can be combined with a digital reconstruction methodology to derive an accurate metal-correction factor that permits subsequent absolute dose-rate response measurements to be derived from laser measurements alone. Broad-area laser dose-rate testing can thereby be used to accurately determine the peak transient current, dose-rate response of semiconductor devices to penetrating electron, gamma- and x-ray irradiation.

  6. Low dose radiation hypersensitivity and clustered DNA damages in human fibroblasts exposed to low dose and dose rate protons or 137CS y-rays

    SciTech Connect (OSTI)

    Bennett P. V.; Bennett, P.V.; Keszenman, D.J.; Johnson, A.M.; Sutherland, B.M.; Wilson, P.F.

    2013-05-14

    Effective radioprotection for human space travelers hinges upon understanding the individual properties of charged particles. A significant fraction of particle radiation astronauts will encounter in space exploratory missions will come from high energy protons in galactic cosmic radiation (GCR) and/or possible exposures to lower energy proton flux from solar particle events (SPEs). These potential exposures present major concerns for NASA and others, in planning and executing long term space exploratory missions. We recently reported cell survival and transformation (acquisition of anchorage-independent growth in soft agar) frequencies in apparently normal NFF-28 primary human fibroblasts exposed to 0-30 cGy of 50MeV, 100MeV (SPE-like), or 1000 MeV (GCR-like) monoenergetic protons. These were modeled after 1989 SPE energies at an SPE-like low dose-rate (LDR) of 1.65 cGy/min or high dose rate (HDR) of 33.3 cGy/min delivered at the NASA Space Radiation Laboratory (NSRL) at BNL.

  7. A METHODOLOGY FOR DETERMINING THE DOSE RATE FOR BOUNDING MASS LIMITS IN A 9977 PACKAGING

    SciTech Connect (OSTI)

    Abramczyk, G.; Bellamy, S.; Nathan, S.; Loftin, B.

    2012-05-24

    The Small Gram Quantity (SGQ) concept is based on the understanding that the hazards associated with the shipment of a radioactive material are directly proportional to its mass. This study describes a methodology that estimates the acceptable masses for several neutron and gamma emitting isotopes that can be shipped in a 9977 Package compliant with the Title 10 of the Code of Federal Regulations, Part 71 (10CFR71) external radiation level limits. 10CFR71.33 states that a shipping application identifies the radioactive and fissile materials at their maximum quantity and provides an evaluation demonstrating compliance with the external radiation standards. Since rather small amounts of some isotopes emit sufficiently strong radiation to produce a large external dose rate, quantifying of the dose rate for a proposed content is a challenging issue for the SGQ approach. It is essential to quantify external radiation levels from several common gamma and neutron sources that can be safely placed in a specific packaging, to ensure compliance with federal regulations. A methodology was established for determining the dose rate for bounding mass limits for a set of isotopes in the Model 9977 Shipping Package. Calculations were performed to estimate external radiation levels using the MCNP radiation transport code to develop a set of response multipliers (Green's functions) for 'dose per source particle' for each neutron and photon spectral group. The source spectrum from one gram of each isotope was folded with the response multipliers to generate the dose rate per gram of each isotope in the 9977 shipping package and its associated shielded containers. The maximum amount of a single isotope that could be shipped within the regulatory limits for dose rate at the surface was determined. For a package containing a mixture of isotopes, the acceptability for shipment can be determined by a sum of fractions approach. Furthermore, the results of this analysis can be easily extended to additional radioisotopes by simply evaluating the neutron and/or photon spectra of those isotopes and folding the spectral data with the Green's functions provided.

  8. Dose rate dependence of the speciation of neptunium in irradiated solutions of nitric acid

    SciTech Connect (OSTI)

    Precek, M.; Paulenova, A.; Mincher, B.J.; Mezyk, S.P.

    2013-07-01

    The effects of radiation on the redox speciation of neptunium are of interest due to their impact on the performance of separation of neptunium from highly radioactive solutions of dissolved used nuclear fuel. In this study, the influence of dose rate change from 0.4 kGy/h to 6 kGy/h was examined during irradiation of solutions of initially hexavalent 2.0-2.5 mM neptunium in nitric acid of two different concentrations (0.5 and 1 M). Results indicate that the immediate radiolytic steady-state concentration of neptunium(V) were depressed and its initial radiolytic yield was up to 2-times lower (in 1 M HNO{sub 3} solutions)during irradiations with the higher dose rate. The finding is explained on the basis of the enhancement of the role of oxidizing radicals during the radiolytic process. (authors)

  9. PACKAGING CERTIFICATION PROGRAM METHODOLOGY FOR DETERMINING DOSE RATES FOR SMALL GRAM QUANTITIES IN SHIPPING PACKAGINGS

    SciTech Connect (OSTI)

    Nathan, S.; Loftin, B.; Abramczyk, G.; Bellamy, S.

    2012-05-09

    The Small Gram Quantity (SGQ) concept is based on the understanding that small amounts of hazardous materials, in this case radioactive materials (RAM), are significantly less hazardous than large amounts of the same materials. This paper describes a methodology designed to estimate an SGQ for several neutron and gamma emitting isotopes that can be shipped in a package compliant with 10 CFR Part 71 external radiation level limits regulations. These regulations require packaging for the shipment of radioactive materials, under both normal and accident conditions, to perform the essential functions of material containment, subcriticality, and maintain external radiation levels within the specified limits. By placing the contents in a helium leak-tight containment vessel, and limiting the mass to ensure subcriticality, the first two essential functions are readily met. Some isotopes emit sufficiently strong photon radiation that small amounts of material can yield a large dose rate outside the package. Quantifying the dose rate for a proposed content is a challenging issue for the SGQ approach. It is essential to quantify external radiation levels from several common gamma and neutron sources that can be safely placed in a specific packaging, to ensure compliance with federal regulations. The Packaging Certification Program (PCP) Methodology for Determining Dose Rate for Small Gram Quantities in Shipping Packagings provides bounding shielding calculations that define mass limits compliant with 10 CFR 71.47 for a set of proposed SGQ isotopes. The approach is based on energy superposition with dose response calculated for a set of spectral groups for a baseline physical packaging configuration. The methodology includes using the MCNP radiation transport code to evaluate a family of neutron and photon spectral groups using the 9977 shipping package and its associated shielded containers as the base case. This results in a set of multipliers for 'dose per particle' for each spectral group. For a given isotope, the source spectrum is folded with the response for each group. The summed contribution from all isotopes determines the total dose from the RAM in the container.

  10. PCP METHODOLOGY FOR DETERMINING DOSE RATES FOR SMALL GRAM QUANTITIES IN SHIPPING PACKAGINGS

    SciTech Connect (OSTI)

    Nathan, S.

    2011-08-23

    The Small Gram Quantity (SGQ) concept is based on the understanding that small amounts of hazardous materials, in this case radioactive materials, are significantly less hazardous than large amounts of the same materials. This study describes a methodology designed to estimate an SGQ for several neutron and gamma emitting isotopes that can be shipped in a package compliant with 10 CFR Part 71 external radiation level limits regulations. These regulations require packaging for the shipment of radioactive materials perform, under both normal and accident conditions, the essential functions of material containment, subcriticality, and maintain external radiation levels within regulatory limits. 10 CFR 71.33(b)(1)(2)&(3) state radioactive and fissile materials must be identified and their maximum quantity, chemical and physical forms be included in an application. Furthermore, the U.S. Federal Regulations require application contain an evaluation demonstrating the package (i.e., the packaging and its contents) satisfies the external radiation standards for all packages (10 CFR 71.31(2), 71.35(a), & 71.47). By placing the contents in a He leak-tight containment vessel, and limiting the mass to ensure subcriticality, the first two essential functions are readily met. Some isotopes emit sufficiently strong photon radiation that small amounts of material can yield a large external dose rate. Quantifying of the dose rate for a proposed content is a challenging issue for the SGQ approach. It is essential to quantify external radiation levels from several common gamma and neutron sources that can be safely placed in a specific packaging, to ensure compliance with federal regulations. The Packaging Certification Program (PCP) Methodology for Determining Dose Rate for Small Gram Quantities in Shipping Packagings described in this report provides bounding mass limits for a set of proposed SGQ isotopes. Methodology calculations were performed to estimate external radiation levels for the 9977 shipping package using the MCNP radiation transport code to develop a set of response multipliers (Green's functions) for 'dose per particle' for each neutron and photon spectral group. The source spectrum for each isotope generated using the ORIGEN-S and RASTA computer codes was folded with the response multipliers to generate the dose rate per gram of each isotope in the 9977 shipping package and its associated shielded containers. The maximum amount of a single isotope that could be shipped within the regulatory limits contained in 10 CFR 71.47 for dose rate at the surface of the package is determined. If a package contains a mixture of isotopes, the acceptability for shipment can be determined by a sum of fractions approach. Furthermore, the results of this analysis can be easily extended to additional radioisotopes by simply evaluating the neutron and/or photon spectra of those isotopes and folding the spectral data with the Green's functions provided.

  11. Special Analysis for the Disposal of the Lawrence Livermore National Laboratory Low Activity Beta/Gamma Sources Waste Stream at the Area 5 Radioactive Waste Management Site, Nevada National Security Site, Nye County, Nevada

    SciTech Connect (OSTI)

    Shott, Gregory J.

    2015-06-01

    This special analysis (SA) evaluates whether the Lawrence Livermore National Laboratory (LLNL) Low Activity Beta/Gamma Sources waste stream (BCLALADOEOSRP, Revision 0) is suitable for disposal by shallow land burial (SLB) at the Area 5 Radioactive Waste Management Site (RWMS) at the Nevada National Security Site (NNSS). The LLNL Low Activity Beta/Gamma Sources waste stream consists of sealed sources that are no longer needed. The LLNL Low Activity Beta/Gamma Sources waste stream required a special analysis because cobalt-60 (60Co), strontium-90 (90Sr), cesium-137 (137Cs), and radium-226 (226Ra) exceeded the NNSS Waste Acceptance Criteria (WAC) Action Levels (U.S. Department of Energy, National Nuclear Security Administration Nevada Field Office [NNSA/NFO] 2015). The results indicate that all performance objectives can be met with disposal of the LLNL Low Activity Beta/Gamma Sources in a SLB trench. The LLNL Low Activity Beta/Gamma Sources waste stream is suitable for disposal by SLB at the Area 5 RWMS. However, the activity concentration of 226Ra listed on the waste profile sheet significantly exceeds the action level. Approval of the waste profile sheet could potentially allow the disposal of high activity 226Ra sources. To ensure that the generator does not include large 226Ra sources in this waste stream without additional evaluation, a control is need on the maximum 226Ra inventory. A limit based on the generator’s estimate of the total 226Ra inventory is recommended. The waste stream is recommended for approval with the control that the total 226Ra inventory disposed shall not exceed 5.5E10 Bq (1.5 Ci).

  12. Laser-based irradiation apparatus and method to measure the functional dose-rate response of semiconductor devices

    DOE Patents [OSTI]

    Horn, Kevin M. (Albuquerque, NM)

    2008-05-20

    A broad-beam laser irradiation apparatus can measure the parametric or functional response of a semiconductor device to exposure to dose-rate equivalent infrared laser light. Comparisons of dose-rate response from before, during, and after accelerated aging of a device, or from periodic sampling of devices from fielded operational systems can determine if aging has affected the device's overall functionality. The dependence of these changes on equivalent dose-rate pulse intensity and/or duration can be measured with the apparatus. The synchronized introduction of external electrical transients into the device under test can be used to simulate the electrical effects of the surrounding circuitry's response to a radiation exposure while exposing the device to dose-rate equivalent infrared laser light.

  13. A GREEN'S FUNCTION APPROACH FOR DETERMINING DOSE RATES FOR SMALL GRAM QUANTITIES IN SHIPPING PACKAGINGS

    SciTech Connect (OSTI)

    Nathan, S.

    2012-06-14

    The Small Gram Quantity (SGQ) concept is based on the understanding that small amounts of hazardous materials, in this case radioactive materials (RAM), are significantly less hazardous than large amounts of the same materials. This paper describes a methodology designed to estimate an SGQ for several neutron and gamma emitting isotopes that can be shipped in a package in compliance with 10 CFR Part 71 external radiation level limits regulations. The neutron and photon sources were calculated using both ORIGEN-S and RASTA. The response from a unit source in each neutron and photon group was calculated using MCNP5 with each unshielded and shielded container configuration. Effects of self-shielding on both neutron and photon response were evaluated by including either plutonium oxide or iron in the source region for the case with no shielded container. For the cases of actinides mixed with light elements, beryllium is the bounding light element. The added beryllium (10 to 90 percent of the actinide mass) in the cases studied represents between 9 and 47 percent concentration of the total mixture mass. For beryllium concentrations larger than 50 percent, the increase in the neutron source term and dose rate tend to increase at a much lower rate than at concentrations lower than 50%. The intimately mixed actinide-beryllium form used in these models is very conservative and thus the limits presented in this report are practical bounds on the mass that can be safely shipped. The calculated dose rate from one gram of each isotope was then used to determin the maximum amount of a single isotope that could be shipped in the Model 9977 Package (or packagings having the same or larger external dimensions as well as similar structural materials) and have the external radiation level within the regulatory dose limits at the surface of the package. The estimates of the mass limits presented would also serve as conservative limits for both the Models 9975 and 9978 packages. If a package contains a mixture of isotopes, the acceptability for shipment can be determined by a sum of fractions approach. It should be noted that the SGQ masses presented in this report represent limits that would comply with the external radiation limits under 10CFR Part 71. They do not necessarily bound lower limits that may be required to comply with other factors such as heat load of the package.

  14. Modification of the effects of continuous low dose rate irradiation by concurrent chemotherapy infusion

    SciTech Connect (OSTI)

    Fu, K.K.; Rayner, P.A.; Lam, K.N.

    1984-08-01

    The combined effects of continuous low dose rate irradiation (CLDRI) and concurrent infusion of bleomycin, cyclophosphamide, cis-platinum, 5-fluorouracil, actinomycin D, and mitomycin C were studied in the SCC VII/SF tumor, a squamous cell carcinoma and the jejunal crypt cells in the mouse. For the SCC VII/SF tumor, enhanced cell killing was seen with each of the six drugs when infused concurrently with CLDRI; the greatest enhancement was seen with mitomycin C and cis-platinum. For the jejunal crypt cells, enhanced cell killing was seen primarily with bleomycin. The authors results suggest a therapeutic gain with concurrent CLDRI and chemotherapy infusion for five of the six chemotherapeutic drugs studied with the exception of bleomycin.

  15. Dose-rate models for human survival after exposure to ionizing radiation

    SciTech Connect (OSTI)

    Jones, T.D.; Morris, M.D.; Young, R.W.

    1986-01-01

    This paper reviews new estimates of the L/sub 50/ in man by Mole and by Rotblat, the biological processes contributing to hematologic death, the collection of animal experiments dealing with hematologic death, and the use of regression analysis to make new estimates of human mortality based on all relevant animal studies. Regression analysis of animal mortality data has shown that mortality is dependent strongly on dose rate, species, body weight, and time interval over which the exposure is delivered. The model has predicted human LD/sub 50/s of 194, 250, 310, and 360 rad to marrow when the exposure time is a minute, an hour, a day, and a week, respectively.

  16. Multi-level effects of low dose rate ionizing radiation on southern toad, Anaxyrus [Bufo] terrestris

    SciTech Connect (OSTI)

    Stark, Karolina; Scott, David E.; Tsyusko, Olga; Coughlin, Daniel P.; Hinton, Thomas G.; Amendola, Roberto

    2015-04-30

    Despite their potential vulnerability to contaminants from exposure at multiple life stages, amphibians are one of the least studied groups of vertebrates in ecotoxicology, and research on radiation effects in amphibians is scarce. We used multiple endpoints to assess the radiosensitivity of the southern toad (Anaxyrus [Bufo] terrestris) during its pre-terrestrial stages of development embryonic, larval, and metamorphic. Toads were exposed, from several hours after oviposition through metamorphosis (up to 77 days later), to four low dose rates of ?Cs at 0.13, 2.4, 21, and 222 mGy d?, resulting in total doses up to 15.8 Gy. Radiation treatments did not affect hatching success of embryos, larval survival, or the length of the larval period. The individual family variation in hatching success of embryos was larger than the radiation response. In contrast, newly metamorphosed individuals from the higher dose-rate treatments had higher mass and mass/length body indices, a measure which may relate to higher post-metamorphic survival. The increased mass and index at higher dose rates may indicate that the chronic, low dose rate radiation exposures triggered secondary responses. Additionally, the increases in growth were linked to a decrease in DNA damage (as measured by the Comet Assay) in red blood cells at a dose rate of 21mGy d? and a total dose of 1.1 Gy. In conclusion, the complex effects of low dose rates of ionizing radiation may trigger growth and cellular repair mechanisms in amphibian larvae.

  17. The Contribution of Tissue Level Organization to Genomic Stability Following Low Dose/Low Dose Rate Gamma and Proton Irradiation

    SciTech Connect (OSTI)

    Cheryl G. Burrell, Ph.D.

    2012-05-14

    The formation of functional tissue units is necessary in maintaining homeostasis within living systems, with individual cells contributing to these functional units through their three-dimensional organization with integrin and adhesion proteins to form a complex extra-cellular matrix (ECM). This is of particular importance in those tissues susceptible to radiation-induced tumor formation, such as epithelial glands. The assembly of epithelial cells of the thyroid is critical to their normal receipt of, and response to, incoming signals. Traditional tissue culture and live animals present significant challenges to radiation exposure and continuous sampling, however, the production of bioreactor-engineered tissues aims to bridge this gap by improve capabilities in continuous sampling from the same functional tissue, thereby increasing the ability to extrapolate changes induced by radiation to animals and humans in vivo. Our study proposes that the level of tissue organization will affect the induction and persistence of low dose radiation-induced genomic instability. Rat thyroid cells, grown in vitro as 3D tissue analogs in bioreactors and as 2D flask grown cultures were exposed to acute low dose (1, 5, 10 and 200 cGy) gamma rays. To assess immediate (6 hours) and delayed (up to 30 days) responses post-irradiation, various biological endpoints were studied including cytogenetic analyses, apoptosis analysis and cell viability/cytotoxicity analyses. Data assessing caspase 3/7 activity levels show that, this activity varies with time post radiation and that, overall, 3D cultures display more genomic instability (as shown by the lower levels of apoptosis over time) when compared to the 2D cultures. Variation in cell viability levels were only observed at the intermediate and late time points post radiation. Extensive analysis of chromosomal aberrations will give further insight on the whether the level of tissue organization influences genomic instability patterns after low dose radiation exposure. Cells viability/cytotoxicity analysis data are currently being analyzed to determine how these endpoints are affected under our experimental conditions. The results from this study will be translatable to risk assessment for assigning limits to radiation workers, pre-dosing for more effective radiotherapy and the consequences of long duration space flight. The data from this study has been presented a various scientific meetings/workshops and a manuscript, containing the findings, is currently being prepared for publication. Due to unforeseen challenges in collecting the data and standardizing experimental procedures, the second and third aims have not been completed. However, attempts will be made, based on the availability of funds, to continue this project so that these aims can be satisfied.

  18. SU-E-T-628: Effect of Dose Rate and Leakage Correction for Dosimetric Leaf Gap Measurement

    SciTech Connect (OSTI)

    Feng, W; Chu, A; Chi, Y; Hu, J

    2014-06-15

    Purpose: To study the dose rate response of Mapcheck and quantify/correct dose rate/leakage effect on IMRT QA. Evaluate the dose rate/leakage effect on dosimetric leaf gap (DLG) measurement. Methods: Varian Truebeam Linac with HD120 MLC was used for all measurement, it is capable to adjust dose rate from 600MU/min to 5MU/min. Fluke Advanced Therapy Doisemter and PTW 30013 Farmer chamber for chamber measurement; SunNuclear Mapcheck2 with 5cm total buildup for diode measurement. DLG was measured with both chamber and diode.Diode response was measured by varies dose rate, while fixed mapcheck setup and total MU. MLC Leakage was measured with both chamber and diode. Mapcheck measurement was saved as movie file (mcm file), which include measurement updated every 50mSec. The difference between intervals can be converted to dose and dose rate and leakage response correction can be applied to them. Results: DLG measurement results with chamber and diode were showed as follows, the DLG value is 0.36 vs. 0.24mm respectively. Diode dose rate response drops from 100% at 600MU/min to 95.5% at 5MU/min as follows. MLC Leakage measured with diode is 1.021%, which is 9% smaller than 1.112% from chamber measurement. By apply the dose rate and leakage correction, the residue error reduced 2/3. Conclusions: Diode has lower response at lower dose rate, as low as 4.5% for 5MU/min; diode has lower energy response for low energy too, 5% lower for Co-60 than 6MV. It partially explains the leakage difference of 9% between chamber and diode. Lower DLG with diode is because of the lower response at narrower gap, in Eclipse however DLG need to increase to makeup lower response, which is over correction for chamber though. Correction can reduce error by 2/3, the rest 1/3 can be corrected by scatter effect, which is under study.

  19. Calculation of the dose rate emanating from gamma radiation of a gas jet propagating through the surface layer of the atmosphere

    SciTech Connect (OSTI)

    Zakharov, O.V.; Kovalenko, V.V.; Kolobashkin, V.M.

    1982-09-01

    The problem of calculating the dose rate on the Earth's surface which emanates from a gas jet is examined.

  20. A generic high-dose rate {sup 192}Ir brachytherapy source for evaluation of model-based dose calculations beyond the TG-43 formalism

    SciTech Connect (OSTI)

    Ballester, Facundo; Carlsson Tedgren, sa; Granero, Domingo; Haworth, Annette; Mourtada, Firas; Fonseca, Gabriel Paiva; Rivard, Mark J.; Siebert, Frank-Andr; Sloboda, Ron S.; and others

    2015-06-15

    Purpose: In order to facilitate a smooth transition for brachytherapy dose calculations from the American Association of Physicists in Medicine (AAPM) Task Group No. 43 (TG-43) formalism to model-based dose calculation algorithms (MBDCAs), treatment planning systems (TPSs) using a MBDCA require a set of well-defined test case plans characterized by Monte Carlo (MC) methods. This also permits direct dose comparison to TG-43 reference data. Such test case plans should be made available for use in the software commissioning process performed by clinical end users. To this end, a hypothetical, generic high-dose rate (HDR) {sup 192}Ir source and a virtual water phantom were designed, which can be imported into a TPS. Methods: A hypothetical, generic HDR {sup 192}Ir source was designed based on commercially available sources as well as a virtual, cubic water phantom that can be imported into any TPS in DICOM format. The dose distribution of the generic {sup 192}Ir source when placed at the center of the cubic phantom, and away from the center under altered scatter conditions, was evaluated using two commercial MBDCAs [Oncentra{sup } Brachy with advanced collapsed-cone engine (ACE) and BrachyVision ACUROS{sup TM}]. Dose comparisons were performed using state-of-the-art MC codes for radiation transport, including ALGEBRA, BrachyDose, GEANT4, MCNP5, MCNP6, and PENELOPE2008. The methodologies adhered to recommendations in the AAPM TG-229 report on high-energy brachytherapy source dosimetry. TG-43 dosimetry parameters, an along-away dose-rate table, and primary and scatter separated (PSS) data were obtained. The virtual water phantom of (201){sup 3} voxels (1 mm sides) was used to evaluate the calculated dose distributions. Two test case plans involving a single position of the generic HDR {sup 192}Ir source in this phantom were prepared: (i) source centered in the phantom and (ii) source displaced 7 cm laterally from the center. Datasets were independently produced by different investigators. MC results were then compared against dose calculated using TG-43 and MBDCA methods. Results: TG-43 and PSS datasets were generated for the generic source, the PSS data for use with the ACE algorithm. The dose-rate constant values obtained from seven MC simulations, performed independently using different codes, were in excellent agreement, yielding an average of 1.1109 0.0004 cGy/(h U) (k = 1, Type A uncertainty). MC calculated dose-rate distributions for the two plans were also found to be in excellent agreement, with differences within type A uncertainties. Differences between commercial MBDCA and MC results were test, position, and calculation parameter dependent. On average, however, these differences were within 1% for ACUROS and 2% for ACE at clinically relevant distances. Conclusions: A hypothetical, generic HDR {sup 192}Ir source was designed and implemented in two commercially available TPSs employing different MBDCAs. Reference dose distributions for this source were benchmarked and used for the evaluation of MBDCA calculations employing a virtual, cubic water phantom in the form of a CT DICOM image series. The implementation of a generic source of identical design in all TPSs using MBDCAs is an important step toward supporting univocal commissioning procedures and direct comparisons between TPSs.

  1. Biologically Effective Dose (BED) Correlation With Biochemical Control After Low-Dose Rate Prostate Brachytherapy for Clinically Low-Risk Prostate Cancer

    SciTech Connect (OSTI)

    Miles, Edward F.; Nelson, John W.; Alkaissi, Ali K.; Das, Shiva; Clough, Robert W.; Broadwater, Gloria; Anscher, Mitchell S.; Chino, Junzo P.; Oleson, James R.

    2010-05-01

    Purpose: To assess the correlation of postimplant dosimetric quantifiers with biochemical control of prostate cancer after low-dose rate brachytherapy. Methods and Materials: The biologically effective dose (BED), dose in Gray (Gy) to 90% of prostate (D{sub 90}), and percent volume of the prostate receiving 100% of the prescription dose (V{sub 100}) were calculated from the postimplant dose-volume histogram for 140 patients undergoing low-dose rate prostate brachytherapy from 1997 to 2003 at Durham Regional Hospital and the Durham VA Medical Center (Durham, NC). Results: The median follow-up was 50 months. There was a 7% biochemical failure rate (10 of 140), and 91% of patients (127 of 140) were alive at last clinical follow-up. The median BED was 148 Gy (range, 46-218 Gy). The median D{sub 90} was 139 Gy (range, 45-203 Gy). The median V{sub 100} was 85% (range, 44-100%). The overall 5-year biochemical relapse-free survival (bRFS) rate was 90.1%. On univariate Cox proportional hazards modeling, no pretreatment characteristic (Gleason score sum, age, baseline prostate-specific antigen, or clinical stage) was predictive of bRFS. The BED, D{sub 90}, and V{sub 100} were all highly correlated (Pearson coefficients >92%), and all were strongly correlated with bRFS. Using the Youden method, we identified the following cut points for predicting freedom from biochemical failure: D{sub 90} >= 110 Gy, V{sub 100} >= 74%, and BED >= 115 Gy. None of the covariates significantly predicted overall survival. Conclusions: We observed significant correlation between BED, D{sub 90}, and V{sub 100} with bRFS. The BED is at least as predictive of bRFS as D{sub 90} or V{sub 100}. Dosimetric quantifiers that account for heterogeneity in tumor location and dose distribution, tumor repopulation, and survival probability of tumor clonogens should be investigated.

  2. Adaptation of the CVT algorithm for catheter optimization in high dose rate brachytherapy

    SciTech Connect (OSTI)

    Poulin, Eric; Fekete, Charles-Antoine Collins; Beaulieu, Luc; Létourneau, Mélanie; Fenster, Aaron; Pouliot, Jean

    2013-11-15

    Purpose: An innovative, simple, and fast method to optimize the number and position of catheters is presented for prostate and breast high dose rate (HDR) brachytherapy, both for arbitrary templates or template-free implants (such as robotic templates).Methods: Eight clinical cases were chosen randomly from a bank of patients, previously treated in our clinic to test our method. The 2D Centroidal Voronoi Tessellations (CVT) algorithm was adapted to distribute catheters uniformly in space, within the maximum external contour of the planning target volume. The catheters optimization procedure includes the inverse planning simulated annealing algorithm (IPSA). Complete treatment plans can then be generated from the algorithm for different number of catheters. The best plan is chosen from different dosimetry criteria and will automatically provide the number of catheters and their positions. After the CVT algorithm parameters were optimized for speed and dosimetric results, it was validated against prostate clinical cases, using clinically relevant dose parameters. The robustness to implantation error was also evaluated. Finally, the efficiency of the method was tested in breast interstitial HDR brachytherapy cases.Results: The effect of the number and locations of the catheters on prostate cancer patients was studied. Treatment plans with a better or equivalent dose distributions could be obtained with fewer catheters. A better or equal prostate V100 was obtained down to 12 catheters. Plans with nine or less catheters would not be clinically acceptable in terms of prostate V100 and D90. Implantation errors up to 3 mm were acceptable since no statistical difference was found when compared to 0 mm error (p > 0.05). No significant difference in dosimetric indices was observed for the different combination of parameters within the CVT algorithm. A linear relation was found between the number of random points and the optimization time of the CVT algorithm. Because the computation time decrease with the number of points and that no effects were observed on the dosimetric indices when varying the number of sampling points and the number of iterations, they were respectively fixed to 2500 and to 100. The computation time to obtain ten complete treatments plans ranging from 9 to 18 catheters, with the corresponding dosimetric indices, was 90 s. However, 93% of the computation time is used by a research version of IPSA. For the breast, on average, the Radiation Therapy Oncology Group recommendations would be satisfied down to 12 catheters. Plans with nine or less catheters would not be clinically acceptable in terms of V100, dose homogeneity index, and D90.Conclusions: The authors have devised a simple, fast and efficient method to optimize the number and position of catheters in interstitial HDR brachytherapy. The method was shown to be robust for both prostate and breast HDR brachytherapy. More importantly, the computation time of the algorithm is acceptable for clinical use. Ultimately, this catheter optimization algorithm could be coupled with a 3D ultrasound system to allow real-time guidance and planning in HDR brachytherapy.

  3. Shutdown Dose Rate Analysis Using the Multi-Step CADIS Method

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

    Ibrahim, Ahmad M.; Peplow, Douglas E.; Peterson, Joshua L.; Grove, Robert E.

    2015-01-01

    The Multi-Step Consistent Adjoint Driven Importance Sampling (MS-CADIS) hybrid Monte Carlo (MC)/deterministic radiation transport method was proposed to speed up the shutdown dose rate (SDDR) neutron MC calculation using an importance function that represents the neutron importance to the final SDDR. This work applied the MS-CADIS method to the ITER SDDR benchmark problem. The MS-CADIS method was also used to calculate the SDDR uncertainty resulting from uncertainties in the MC neutron calculation and to determine the degree of undersampling in SDDR calculations because of the limited ability of the MC method to tally detailed spatial and energy distributions. The analysismore » that used the ITER benchmark problem compared the efficiency of the MS-CADIS method to the traditional approach of using global MC variance reduction techniques for speeding up SDDR neutron MC calculation. Compared to the standard Forward-Weighted-CADIS (FW-CADIS) method, the MS-CADIS method increased the efficiency of the SDDR neutron MC calculation by 69%. The MS-CADIS method also increased the fraction of nonzero scoring mesh tally elements in the space-energy regions of high importance to the final SDDR.« less

  4. Adherence to Vaginal Dilation Following High Dose Rate Brachytherapy for Endometrial Cancer

    SciTech Connect (OSTI)

    Friedman, Lois C., E-mail: Lois.Friedman@UHhospitals.org [Department of Psychiatry, CASE Comprehensive Cancer Center and University Hospitals of Cleveland, Cleveland, OH (United States); Abdallah, Rita [Ireland Cancer Center, CASE Comprehensive Cancer Center and University Hospitals of Cleveland, Cleveland, OH (Ireland); Schluchter, Mark; Panneerselvam, Ashok [Department of Epidemiology and Biostatistics, CASE Comprehensive Cancer Center and University Hospitals of Cleveland, Cleveland, OH (United States); Kunos, Charles A. [Department of Radiation Oncology, CASE Comprehensive Cancer Center and University Hospitals of Cleveland, Cleveland, OH (United States)

    2011-07-01

    Purpose: We report demographic, clinical, and psychosocial factors associated with adherence to vaginal dilation and describe the sexual and marital or nonmarital dyadic functioning of women following high dose rate (HDR) brachytherapy for endometrial cancer. Methods and Materials: We retrospectively evaluated women aged 18 years or older in whom early-stage endometrial (IAgr3-IIB) cancers were treated by HDR intravaginal brachytherapy within the past 3.5 years. Women with or without a sexual partner were eligible. Patients completed questionnaires by mail or by telephone assessing demographic and clinical variables, adherence to vaginal dilation, dyadic satisfaction, sexual functioning, and health beliefs. Results: Seventy-eight of 89 (88%) eligible women with early-stage endometrial cancer treated with HDR brachytherapy completed questionnaires. Only 33% of patients were adherers, based on reporting having used a dilator more than two times per week in the first month following radiation. Nonadherers who reported a perceived change in vaginal dimension following radiation reported that their vaginas were subjectively smaller after brachytherapy (p = 0.013). Adherers reported more worry about their sex lives or lack thereof than nonadherers (p = 0.047). Patients reported considerable sexual dysfunction following completion of HDR brachytherapy. Conclusions: Adherence to recommendations for vaginal dilator use following HDR brachytherapy for endometrial cancer is poor. Interventions designed to educate women about dilator use benefit may increase adherence. Although sexual functioning was compromised, it is likely that this existed before having cancer for many women in our study.

  5. Shutdown Dose Rate Analysis Using the Multi-Step CADIS Method

    SciTech Connect (OSTI)

    Ibrahim, Ahmad M.; Peplow, Douglas E.; Peterson, Joshua L.; Grove, Robert E.

    2015-01-01

    The Multi-Step Consistent Adjoint Driven Importance Sampling (MS-CADIS) hybrid Monte Carlo (MC)/deterministic radiation transport method was proposed to speed up the shutdown dose rate (SDDR) neutron MC calculation using an importance function that represents the neutron importance to the final SDDR. This work applied the MS-CADIS method to the ITER SDDR benchmark problem. The MS-CADIS method was also used to calculate the SDDR uncertainty resulting from uncertainties in the MC neutron calculation and to determine the degree of undersampling in SDDR calculations because of the limited ability of the MC method to tally detailed spatial and energy distributions. The analysis that used the ITER benchmark problem compared the efficiency of the MS-CADIS method to the traditional approach of using global MC variance reduction techniques for speeding up SDDR neutron MC calculation. Compared to the standard Forward-Weighted-CADIS (FW-CADIS) method, the MS-CADIS method increased the efficiency of the SDDR neutron MC calculation by 69%. The MS-CADIS method also increased the fraction of nonzero scoring mesh tally elements in the space-energy regions of high importance to the final SDDR.

  6. Laser-based irradiation apparatus and methods for monitoring the dose-rate response of semiconductor devices

    DOE Patents [OSTI]

    Horn, Kevin M. (Albuquerque, NM)

    2006-03-28

    A scanned, pulsed, focused laser irradiation apparatus can measure and image the photocurrent collection resulting from a dose-rate equivalent exposure to infrared laser light across an entire silicon die. Comparisons of dose-rate response images or time-delay images from before, during, and after accelerated aging of a device, or from periodic sampling of devices from fielded operational systems allows precise identification of those specific age-affected circuit structures within a device that merit further quantitative analysis with targeted materials or electrical testing techniques. Another embodiment of the invention comprises a broad-beam, dose rate-equivalent exposure apparatus. The broad-beam laser irradiation apparatus can determine if aging has affected the device's overall functionality. This embodiment can be combined with the synchronized introduction of external electrical transients into a device under test to simulate the electrical effects of the surrounding circuitry's response to a radiation exposure.

  7. DOSE RATES FOR WESTINGHOUSE 17X17 MOX PWR SNF IN A WASTE PACKAGE (SCPB: N/A)

    SciTech Connect (OSTI)

    T.L. Lotz

    1997-01-29

    This analysis is prepared by the Mined Geologic Disposal System (MGDS) Waste Package Development Department (WPDD) to estimate the dose rate on and near the surface a Multi-Purpose Canister (MPC) PWR waste package (WP) which is loaded with Westinghouse 17 x 17 mixed oxide (MOX) PWR fuel. The 21 PWR MPC WP is used to provide an upper bound for waste package designs since the 12 PWR MPC WP will have a smaller source term and an equivalent amount of shielding. the objectives of this evaluation are to calculate the requested dose rate(s) and document the calculation in a fashion to allow comparisons to other waste forms and WP designs at a future time.

  8. Investigations of DNA damage induction and repair resulting from cellular exposure to high dose-rate pulsed proton beams

    SciTech Connect (OSTI)

    Renis, M.; Malfa, G.; Tomasello, B.; Borghesi, M.; Schettino, G.; Favetta, M.; Romano, F.; Cirrone, G. A. P.; Manti, L.

    2013-07-26

    Studies regarding the radiobiological effects of low dose radiation, microbeam irradiation services have been developed in the world and today laser acceleration of protons and heavy ions may be used in radiation therapy. The application of different facilities is essential for studying bystander effects and relating signalling phenomena in different cells or tissues. In particular the use of ion beams results advantageous in cancer radiotherapy compared to more commonly used X-rays, since the ability of ions in delivering lethal amount of doses into the target tumour avoiding or limiting damage to the contiguous healthy tissues. At the INFN-LNS in Catania, a multidisciplinary radiobiology group is strategically structured aimed to develop radiobiological research, finalised to therapeutic applications, compatible with the use of high dose laser-driven ion beams. The characteristic non-continuous dose rates with several orders of magnitude of laser-driven ion beams makes this facility very interesting in the cellular systems' response to ultra-high dose rates with non-conventional pulse time intervals cellular studies. Our group have projected to examine the effect of high dose laser-driven ion beams on two cellular types: foetal fibroblasts (normal control cells) and DU145 (prostate cancer cells), studying the modulation of some different bio-molecular parameters, in particular cell proliferation and viability, DNA damage, redox cellular status, morphological alterations of both the cytoskeleton components and some cell organelles and the possible presence of apoptotic or necrotic cell death. Our group performed preliminary experiments with high energy (60 MeV), dose rate of 10 Gy/min, doses of 1, 2, 3 Gy and LET 1 keV/?m on human foetal fibroblasts (control cells). We observed that cell viability was not influenced by the characteristics of the beam, the irradiation conditions or the analysis time. Conversely, DNA damage was present at time 0, immediately following irradiation in a dose-dependent manner. The analysis of repair capability showed that the cells irradiated with 1 and 2 Gy almost completely recovered from the damage, but not, however, 3 Gy treated cells in which DNA damage was not recovered. In addition, the results indicate the importance of the use of an appropriate control in radiobiological in vitro analysis.

  9. Modeling of transient ionizing radiation effects in bipolar devices at high dose-rates

    SciTech Connect (OSTI)

    FJELDLY,T.A.; DENG,Y.; SHUR,M.S.; HJALMARSON,HAROLD P.; MUYSHONDT,ARNOLDO

    2000-04-25

    To optimally design circuits for operation at high intensities of ionizing radiation, and to accurately predict their a behavior under radiation, precise device models are needed that include both stationary and dynamic effects of such radiation. Depending on the type and intensity of the ionizing radiation, different degradation mechanisms, such as photoelectric effect, total dose effect, or single even upset might be dominant. In this paper, the authors consider the photoelectric effect associated with the generation of electron-hole pairs in the semiconductor. The effects of low radiation intensity on p-II diodes and bipolar junction transistors (BJTs) were described by low-injection theory in the classical paper by Wirth and Rogers. However, in BJTs compatible with modem integrated circuit technology, high-resistivity regions are often used to enhance device performance, either as a substrate or as an epitaxial layer such as the low-doped n-type collector region of the device. Using low-injection theory, the transient response of epitaxial BJTs was discussed by Florian et al., who mainly concentrated on the effects of the Hi-Lo (high doping - low doping) epilayer/substrate junction of the collector, and on geometrical effects of realistic devices. For devices with highly resistive regions, the assumption of low-level injection is often inappropriate, even at moderate radiation intensities, and a more complete theory for high-injection levels was needed. In the dynamic photocurrent model by Enlow and Alexander. p-n junctions exposed to high-intensity radiation were considered. In their work, the variation of the minority carrier lifetime with excess carrier density, and the effects of the ohmic electric field in the quasi-neutral (q-n) regions were included in a simplified manner. Later, Wunsch and Axness presented a more comprehensive model for the transient radiation response of p-n and p-i-n diode geometries. A stationary model for high-level injection in p-n junctions was developed by Isaque et al. They used a more complete ambipolar transport equation, which included the dependencies of the transport parameters (ambipolar diffusion constant, mobility, and recombination rate) on the excess minority carrier concentration. The expression used for the recombination rate was that of Shockley-Reed-Hall (SRH) recombination which is dominant for low to mid-level radiation intensities. However, at higher intensities, Auger recombination becomes important eventually dominant. The complete ambipolar transport equation including the complicated dependence of transport parameters on the radiation intensity, cannot be solved analytically. This solution is obtained for each of the regimes where a given recombination mechanism dominates, and then by joining these solutions using appropriate smoothing functions. This approach allows them to develop a BJT model accounting for the photoelectric effect of the ionizing radiation that can be implemented in SPICE.

  10. SU-E-T-421: Feasibility Study of Volumetric Modulated Arc Therapy with Constant Dose Rate for Endometrial Cancer

    SciTech Connect (OSTI)

    Yang, R; Wang, J

    2014-06-01

    Purpose: To investigate the feasibility, efficiency, and delivery accuracy of volumetric modulated arc therapy with constant dose rate (VMAT-CDR) for whole-pelvic radiotherapy (WPRT) of endometrial cancer. Methods: The nine-Field intensity-modulated radiotherapy (IMRT), VMAT with variable dose-rate (VMAT-VDR), and VMAT-CDR plans were created for 9 patients with endometrial cancer undergoing WPRT. The dose distribution of planning target volume (PTV), organs at risk (OARs), and normal tissue (NT) were compared. The monitor units (MUs) and treatment delivery time were also evaluated. For each VMAT-CDR plan, a dry Run was performed to assess the dosimetric accuracy with MatriXX from IBA. Results: Compared with IMRT, the VMAT-CDR plans delivered a slightly greater V20 of the bowel, bladder, pelvis bone, and NT, but significantly decreased the dose to the high-dose region of the rectum and pelvis bone. The MUs Decreased from 1105 with IMRT to 628 with VMAT-CDR. The delivery time also decreased from 9.5 to 3.2 minutes. The average gamma pass rate was 95.6% at the 3%/3 mm criteria with MatriXX pretreatment verification for 9 patients. Conclusion: VMAT-CDR can achieve comparable plan quality with significant shorter delivery time and smaller number of MUs compared with IMRT for patients with endometrial cancer undergoing WPRT. It can be accurately delivered and be an alternative to IMRT on the linear accelerator without VDR capability. This work is supported by the grant project, National Natural; Science Foundation of China (No. 81071237)

  11. SU-E-T-34: An in Vivo Study On Pulsed Low Dose-Rate Radiotherapy for Prostate Cancer

    SciTech Connect (OSTI)

    Wang, B; Cvetkovic, D; Chen, L; Ma, C; Chen, X; Zhang, P; Zhang, C

    2014-06-01

    Purpose: Re-irradiation with conventional radiotherapy techniques (CRT) may pose significant risks due to high accumulative radiation doses. Pulsed low dose-rate radiotherapy (PLDR) has been used in clinical trials for recurrent cancer treatment. In our previous studies, PLDR irradiation showed significantly lower toxicity than CRT, resulting in much longer survival of mice after PLDR total body irradiation (TBI) than conventional TBI. The purpose of this study was to investigate tumor control efficacy of PLDR treatment for prostate cancer with an animal model of prostate cancer LNCaP. Methods: We used an orthotopic murine model of LNCaP cell line for this study. LNCaP cells were implanted into immune-suppressed male nude mice via surgery. We monitored the tumor growth with MRI. The tumor-bearing mice were allocated into a PLDR(n=9), CRT(n=7), and control group(n=7) randomly. The mice in the PLDR and CRT groups were irradiated with 2Gy dose for one time. For the CRT treatment, the mice received 2Gy at a dose-rate of 300 MU/minute. For the PLDR treatment, the 2Gy dose was further divided into ten pulses of 0.2Gy at the same dose-rate with an interval of 3 minutes between the pulses. Results: Sizable tumor growth delays were observed for the PLDR and CRT groups through weekly MRI scans. The mean values of the normalized tumor volumes ( standard deviation of the mean) were 1.530.07, 1.530.14, and 1.810.09 at one week after treatment, 2.280.13, 2.190.16, and 3.040.25 at two weeks after treatment, and 3.310.23, 3.140.24 and 4.620.49 at three weeks after treatment, for the PLDR, CRT, and control groups, respectively. Conclusion: The PLDR and CRT treatments showed comparable tumor control rates in this study. Our in vivo results indicate that PLDR may be a viable option for treating recurrent prostate cancer due to its equivalent tumor control but low normal tissue toxocities.

  12. Outcomes of High-Dose-Rate Interstitial Brachytherapy in the Treatment of Locally Advanced Cervical Cancer: Long-term Results

    SciTech Connect (OSTI)

    Pinn-Bingham, Melva; Puthawala, Ajmel A.; Syed, A.M. Nisar; Sharma, Anil; DiSaia, Philip; Berman, Michael; Tewari, Krishnansu S.; Randall-Whitis, Leslie; Mahmood, Usama; Ramsinghani, Nilam; Kuo, Jeffrey; Chen, Wen-Pin; McLaren, Christine E.

    2013-03-01

    Purpose: The purpose of this study was to determine locoregional control (LRC), disease-free survival (DFS), and toxicity of high-dose-rate interstitial brachytherapy (HDR-ISBT) in the treatment of locally advanced cervical cancer. Methods and Materials: Between March 1996 and May 2009, 116 patients with cervical cancer were treated. Of these, 106 (91%) patients had advanced disease (International Federation of Gynecology and Obstetrics stage IIB-IVA). Ten patients had stage IB, 48 had stage II, 51 had stage III, and 7 had stage IVA disease. All patients were treated with a combination of external beam radiation therapy (EBRT) to the pelvis (5040 cGy) and 2 applications of HDR-ISBT to a dose of 3600 cGy to the implanted volume. Sixty-one percent of patients also received interstitial hyperthermia, and 94 (81%) patients received chemotherapy. Results: Clinical LRC was achieved in 99 (85.3%) patients. Three-year DFS rates were 59%, 67%, 71%, and 57% for patients with stage IB, II, III, and IVA disease, respectively. The 5-year DFS and overall survival rates for the entire group were 60% and 44%, respectively. Acute and late toxicities were within acceptable limits. Conclusions: Locally advanced cervical cancer patients for whom intracavitary BT is unsuitable can achieve excellent LRC and OS with a combination of EBRT and HDR-ISBT.

  13. Determination of Radioisotope Content by Measurement of Waste Package Dose Rates - 13394

    SciTech Connect (OSTI)

    Souza, Daiane Cristini B.; Gimenes Tessaro, Ana Paula; Vicente, Roberto

    2013-07-01

    The objective of this communication is to report the observed correlation between the calculated air kerma rates produced by radioactive waste drums containing untreated ion-exchange resin and activated charcoal slurries with the measured radiation field of each package. Air kerma rates at different distances from the drum surface were calculated with the activity concentrations previously determined by gamma spectrometry of waste samples and the estimated mass, volume and geometry of solid and liquid phases of each waste package. The water content of each waste drum varies widely between different packages. Results will allow determining the total activity of wastes and are intended to complete the previous steps taken to characterize the radioisotope content of wastes packages. (authors)

  14. Assessment of the point-source method for estimating dose rates to members of the public from exposure to patients with 131I thyroid treatment

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

    Dewji, Shaheen Azim; Bellamy, Michael B.; Hertel, Nolan E.; Leggett, Richard Wayne; Sherbini, Sami; Saba, Mohammad S.; Eckerman, Keith F.

    2015-09-01

    The U.S. Nuclear Regulatory Commission (USNRC) initiated a contract with Oak Ridge National Laboratory (ORNL) to calculate radiation dose rates to members of the public that may result from exposure to patients recently administered iodine-131 (131I) as part of medical therapy. The main purpose was to compare dose rate estimates based on a point source and target with values derived from more realistic simulations that considered the time-dependent distribution of 131I in the patient and attenuation of emitted photons by the patient’s tissues. The external dose rate estimates were derived using Monte Carlo methods and two representations of the Phantommore » with Movable Arms and Legs, previously developed by ORNL and the USNRC, to model the patient and a nearby member of the public. Dose rates to tissues and effective dose rates were calculated for distances ranging from 10 to 300 cm between the phantoms and compared to estimates based on the point-source method, as well as to results of previous studies that estimated exposure from 131I patients. The point-source method overestimates dose rates to members of the public in very close proximity to an 131I patient but is a broadly accurate method of dose rate estimation at separation distances of 300 cm or more at times closer to administration.« less

  15. Assessment of the point-source method for estimating dose rates to members of the public from exposure to patients with 131I thyroid treatment

    SciTech Connect (OSTI)

    Dewji, Shaheen Azim; Bellamy, Michael B.; Hertel, Nolan E.; Leggett, Richard Wayne; Sherbini, Sami; Saba, Mohammad S.; Eckerman, Keith F.

    2015-09-01

    The U.S. Nuclear Regulatory Commission (USNRC) initiated a contract with Oak Ridge National Laboratory (ORNL) to calculate radiation dose rates to members of the public that may result from exposure to patients recently administered iodine-131 (131I) as part of medical therapy. The main purpose was to compare dose rate estimates based on a point source and target with values derived from more realistic simulations that considered the time-dependent distribution of 131I in the patient and attenuation of emitted photons by the patients tissues. The external dose rate estimates were derived using Monte Carlo methods and two representations of the Phantom with Movable Arms and Legs, previously developed by ORNL and the USNRC, to model the patient and a nearby member of the public. Dose rates to tissues and effective dose rates were calculated for distances ranging from 10 to 300 cm between the phantoms and compared to estimates based on the point-source method, as well as to results of previous studies that estimated exposure from 131I patients. The point-source method overestimates dose rates to members of the public in very close proximity to an 131I patient but is a broadly accurate method of dose rate estimation at separation distances of 300 cm or more at times closer to administration.

  16. SU-E-T-546: Use of Implant Volume for Quality Assurance of Low Dose Rate Brachytherapy Treatment Plans

    SciTech Connect (OSTI)

    Wilkinson, D; Kolar, M

    2014-06-01

    Purpose: To analyze the application of volume implant (V100) data as a method for a global check of low dose rate (LDR) brachytherapy plans. Methods: Treatment plans for 335 consecutive patients undergoing permanent seed implants for prostate cancer and for 113 patients treated with plaque therapy for ocular melanoma were analyzed. Plaques used were 54 COMS (10 to 20 mm, notched and regular) and 59 Eye Physics EP917s with variable loading. Plots of treatment time x implanted activity per unit dose versus v100 ^.667 were made. V100 values were obtained using dose volume histograms calculated by the treatment planning systems (Variseed 8.02 and Plaque Simulator 5.4). Four different physicists were involved in planning the prostate seed cases; two physicists for the eye plaques. Results: Since the time and dose for the prostate cases did not vary, a plot of implanted activity vs V100 ^.667 was made. A linear fit with no intercept had an r{sup 2} = 0.978; more than 94% of the actual activities fell within 5% of the activities calculated from the linear fit. The greatest deviations were in cases where the implant volumes were large (> 100 cc). Both COMS and EP917 plaque linear fits were good (r{sup 2} = .967 and .957); the largest deviations were seen for large volumes. Conclusions: The method outlined here is effective for checking planning consistency and quality assurance of two types of LDR brachytherapy treatment plans (temporary and permanent). A spreadsheet for the calculations enables a quick check of the plan in situations were time is short (e.g. OR-based prostate planning)

  17. Risk of Low Dose/Low Dose Rate Ionizing Radiation to Humans Symposium at the EMS 2009 Annual Meeting - September 2006

    SciTech Connect (OSTI)

    Morgan, William F.; von Borstel, Robert C.; Brenner, David; Redpath, J. Leslie; Erickson, Barbra E.; Brooks, Antone L.

    2009-11-12

    The low dose symposium thoughtfully addressed controversy of risk from low dose radiation exposure, hormesis and radon therapy. The stem cell symposium cogently considered the role of DNA damage and repair in hematopoietic stem cells underlying aging and malignancy and provocatively presented evidence that stem cells may have distinct morphologies and replicative properties, as well as special roles in cancer initiation. In the epigenetics symposium, studies illustrated the long range interaction of epigenetic mechanisms, the roles of CTCF and BORIS in region/specific regulation of epigenetic processes, the impact of DNA damage on epigenetic processes as well as links between epigenetic mechanisms and early nutrition and bystander effects.

  18. Characterization of the neutron irradiation system for use in the Low-Dose-Rate Irradiation Facility at Sandia National Laboratories.

    SciTech Connect (OSTI)

    Franco, Manuel,

    2014-08-01

    The objective of this work was to characterize the neutron irradiation system consisting of americium-241 beryllium (241AmBe) neutron sources placed in a polyethylene shielding for use at Sandia National Laboratories (SNL) Low Dose Rate Irradiation Facility (LDRIF). With a total activity of 0.3 TBq (9 Ci), the source consisted of three recycled 241AmBe sources of different activities that had been combined into a single source. The source in its polyethylene shielding will be used in neutron irradiation testing of components. The characterization of the source-shielding system was necessary to evaluate the radiation environment for future experiments. Characterization of the source was also necessary because the documentation for the three component sources and their relative alignment within the Special Form Capsule (SFC) was inadequate. The system consisting of the source and shielding was modeled using Monte Carlo N-Particle transport code (MCNP). The model was validated by benchmarking it against measurements using multiple techniques. To characterize the radiation fields over the full spatial geometry of the irradiation system, it was necessary to use a number of instruments of varying sensitivities. First, the computed photon radiography assisted in determining orientation of the component sources. With the capsule properly oriented inside the shielding, the neutron spectra were measured using a variety of techniques. A N-probe Microspec and a neutron Bubble Dosimeter Spectrometer (BDS) set were used to characterize the neutron spectra/field in several locations. In the third technique, neutron foil activation was used to ascertain the neutron spectra. A high purity germanium (HPGe) detector was used to characterize the photon spectrum. The experimentally measured spectra and the MCNP results compared well. Once the MCNP model was validated to an adequate level of confidence, parametric analyses was performed on the model to optimize for potential experimental configurations and neutron spectra for component irradiation. The final product of this work is a MCNP model validated by measurements, an overall understanding of neutron irradiation system including photon/neutron transport and effective dose rates throughout the system, and possible experimental configurations for future irradiation of components.

  19. Comparison of methods for the measurement of radiation dose distributions in high dose rate (HDR) brachytherapy: Ge-doped optical fiber, EBT3 Gafchromic film, and PRESAGE{sup Registered-Sign} radiochromic plastic

    SciTech Connect (OSTI)

    Palmer, A. L.; Di Pietro, P.; Alobaidli, S.; Issa, F.; Doran, S.; Bradley, D.; Nisbet, A.

    2013-06-15

    Purpose: Dose distribution measurement in clinical high dose rate (HDR) brachytherapy is challenging, because of the high dose gradients, large dose variations, and small scale, but it is essential to verify accurate treatment planning and treatment equipment performance. The authors compare and evaluate three dosimetry systems for potential use in brachytherapy dose distribution measurement: Ge-doped optical fibers, EBT3 Gafchromic film with multichannel analysis, and the radiochromic material PRESAGE{sup Registered-Sign} with optical-CT readout. Methods: Ge-doped SiO{sub 2} fibers with 6 {mu}m active core and 5.0 mm length were sensitivity-batched and their thermoluminescent properties used via conventional heating and annealing cycles. EBT3 Gafchromic film of 30 {mu}m active thickness was calibrated in three color channels using a nominal 6 MV linear accelerator. A 48-bit transmission scanner and advanced multichannel analysis method were utilized to derive dose measurements. Samples of the solid radiochromic polymer PRESAGE{sup Registered-Sign }, 60 mm diameter and 100 mm height, were analyzed with a parallel beam optical CT scanner. Each dosimetry system was used to measure the dose as a function of radial distance from a Co-60 HDR source, with results compared to Monte Carlo TG-43 model data. Each system was then used to measure the dose distribution along one or more lines through typical clinical dose distributions for cervix brachytherapy, with results compared to treatment planning system (TPS) calculations. Purpose-designed test objects constructed of Solid Water and held within a full-scatter water tank were utilized. Results: All three dosimetry systems reproduced the general shape of the isolated source radial dose function and the TPS dose distribution. However, the dynamic range of EBT3 exceeded those of doped optical fibers and PRESAGE{sup Registered-Sign }, and the latter two suffered from unacceptable noise and artifact. For the experimental conditions used in this study, the useful range from an isolated HDR source was 5-40 mm for fibers, 3-50 mm for EBT3, and 4-21 mm for PRESAGE{sup Registered-Sign }. Fibers demonstrated some over-response at very low dose levels, suffered from volume averaging effects in the dose distribution measurement, and exhibited up to 9% repeatability variation over three repeated measurements. EBT3 demonstrated excellent agreement with Monte Carlo and TPS dose distributions, with up to 3% repeatability over three measurements. PRESAGE{sup Registered-Sign} gave promising results, being the only true 3D dosimeter, but artifacts and noise were apparent. Conclusions: The comparative response of three emerging dosimetry systems for clinical brachytherapy dose distribution measurement has been investigated. Ge-doped optical fibers have excellent spatial resolution for single-direction measurement but are currently too large for complex dose distribution assessment. The use of PRESAGE{sup Registered-Sign} with optical-CT readout gave promising results in the measurement of true 3D dose distributions but further development work is required to reduce noise and improve dynamic range for brachytherapy dose distribution measurements. EBT3 Gafchromic film with multichannel analysis demonstrated accurate and reproducible measurement of dose distributions in HDR brachytherapy. Calibrated dose measurements were possible with agreement within 1.5% of TPS dose calculations. The suitability of EBT3 as a dosimeter for 2D quality control or commissioning work has been demonstrated.

  20. ITER Generic Diagnostic Upper Port Plug Nuclear Heating and Personnel Dose Rate Assesment Neutronics Analysis using the ATTILA Discrete Ordinates Code

    SciTech Connect (OSTI)

    Russell Feder and Mahmoud Z. Yousef

    2009-05-29

    Neutronics analysis to find nuclear heating rates and personnel dose rates were conducted in support of the integration of diagnostics in to the ITER Upper Port Plugs. Simplified shielding models of the Visible-Infrared diagnostic and of the ECH heating system were incorporated in to the ITER global CAD model. Results for these systems are representative of typical designs with maximum shielding and a small aperture (Vis-IR) and minimal shielding with a large aperture (ECH). The neutronics discrete-ordinates code ATTILA and SEVERIAN (the ATTILA parallel processing version) was used. Material properties and the 500 MW D-T volume source were taken from the ITER Brand Model MCNP benchmark model. A biased quadrature set equivelant to Sn=32 and a scattering degree of Pn=3 were used along with a 46-neutron and 21-gamma FENDL energy subgrouping. Total nuclear heating (neutron plug gamma heating) in the upper port plugs ranged between 380 and 350 kW for the Vis-IR and ECH cases. The ECH or Large Aperture model exhibited lower total heating but much higher peak volumetric heating on the upper port plug structure. Personnel dose rates are calculated in a three step process involving a neutron-only transport calculation, the generation of activation volume sources at pre-defined time steps and finally gamma transport analyses are run for selected time steps. ANSI-ANS 6.1.1 1977 Flux-to-Dose conversion factors were used. Dose rates were evaluated for 1 full year of 500 MW DT operation which is comprised of 3000 1800-second pulses. After one year the machine is shut down for maintenance and personnel are permitted to access the diagnostic interspace after 2-weeks if dose rates are below 100 ?Sv/hr. Dose rates in the Visible-IR diagnostic model after one day of shutdown were 130 ?Sv/hr but fell below the limit to 90 ?Sv/hr 2-weeks later. The Large Aperture or ECH style shielding model exhibited higher and more persistent dose rates. After 1-day the dose rate was 230 ?Sv/hr but was still at 120 ?Sv/hr 4-weeks later. __________________________________________________

  1. An apparatus for the study of high temperature water radiolysis in a nuclear reactor: Calibration of dose in a mixed neutron/gamma radiation field

    SciTech Connect (OSTI)

    Edwards, Eric J.; Wilson, Paul P. H.; Anderson, Mark H.; Mezyk, Stephen P.; Pimblott, Simon M.; Bartels, David M.

    2007-12-15

    The cooling water of nuclear reactors undergoes radiolytic decomposition induced by gamma, fast electron, and neutron radiation in the core. To model the process, recombination reaction rates and radiolytic yields for the water radical fragments need to be measured at high temperature and pressure. Yields for the action of neutron radiation are particularly hard to determine independently because of the beta/gamma field also present in any reactor. In this paper we report the design of an apparatus intended to measure neutron radiolysis yields as a function of temperature and pressure. A new methodology for separation of neutron and beta/gamma radiolysis yields in a mixed radiation field is proposed and demonstrated.

  2. Poster Thur Eve 36: Implementation of constant dose rate and gantry speed arc therapy(CDR-CAS-IMAT) for thoracic esophageal carcinoma on Varian 23EX

    SciTech Connect (OSTI)

    Zhang, Ruohui; Fan, Xiaomei; Bai, Wenwen; Han, Chun

    2014-08-15

    Objective: The purpose of this study is to propose an alternative planning approach for VMAT using constant dose rate and gantry speed arc therapy(CDR-CAS-IMAT) implementation on conventional Linac Varian 23EX and used IMRT as a benchmark to evaluate the performance. Methods and materials: Eighteen patients with thoracic esophageal carcinoma who were previously treated with IMRT on Varian 23EX were retrospectively planned for CDR-CAS-IMAT plans. Dose prescription was set to 60 Gy to PTVs in 30 fractions. The planning objectives for PTVs and OAR were corresponding with the IMRT plans. Dose to the PTVs and OAR were compared to IMRT with respect to plan quality, MU, treatment time and delivery accuracy. Results: CDR-CAS-IMAT plans led to equivalent or superior plan quality as compared to IMRT, PTV's CI relative increased 16.2%, while small deviations were observed on minimum dose for PTV. Volumes in the cord receiving 40Gy were increased from 3.6% with IMRT to 7.0%. Treatment times were reduced significantly with CDR-CAS-IMAT(mean 85.7s vs. 232.1s, p < .05), however, MU increased by a factor of 1.3 and lung V10/5/3.5/aver were relative increase 6.7%,12%,17.9%,4.2%, respectively. And increased the E-P low dose area volume decreased the hight dose area. There were no significant difference in Delta4 measurements results between both planning techniques. Conclusion: CDR-CAS-IMAT plans can be implemented smoothly and quickly into a busy cancer center, which improved PTV CI and reduces treatment time but increased the MU and low dose irradiated area. An evaluation of weight loss must be performed during treatment for CDR-CAS-IMAT patients.

  3. Inspection and Gamma-Ray Dose Rate Measurements of the Annulus of the VSC-17 Concrete Spent Nuclear Fuel Storage Cask

    SciTech Connect (OSTI)

    P. L. Winston

    2007-09-01

    The air cooling annulus of the Ventilated Storage Cask (VSC)-17 spent fuel storage cask was inspected using a Toshiba 7 mm (1/4) CCD video camera. The dose rates observed in the annular space were measured to provide a reference for the activity to which the camera(s) being tested were being exposed. No gross degradation, pitting, or general corrosion was observed.

  4. SU-E-T-501: Normal Tissue Toxicities of Pulsed Low Dose Rate Radiotherapy and Conventional Radiotherapy: An in Vivo Total Body Irradiation Study

    SciTech Connect (OSTI)

    Cvetkovic, D; Zhang, P; Wang, B; Chen, L; Ma, C

    2014-06-01

    Purpose: Pulsed low dose rate radiotherapy (PLDR) is a re-irradiation technique for therapy of recurrent cancers. We have previously shown a significant difference in the weight and survival time between the mice treated with conventional radiotherapy (CRT) and PLDR using total body irradiation (TBI). The purpose of this study was to investigate the in vivo effects of PLDR on normal mouse tissues.Materials and Methods: Twenty two male BALB/c nude mice, 4 months of age, were randomly assigned into a PLDR group (n=10), a CRT group (n=10), and a non-irradiated control group (n=2). The Siemens Artiste accelerator with 6 MV photon beams was used. The mice received a total of 18Gy in 3 fractions with a 20day interval. The CRT group received the 6Gy dose continuously at a dose rate of 300 MU/min. The PLDR group was irradiated with 0.2Gyx20 pulses with a 3min interval between the pulses. The mice were weighed thrice weekly and sacrificed 2 weeks after the last treatment. Brain, heart, lung, liver, spleen, gastrointestinal, urinary and reproductive organs, and sternal bone marrow were removed, formalin-fixed, paraffin-embedded and stained with H and E. Morphological changes were observed under a microscope. Results: Histopathological examination revealed atrophy in several irradiated organs. The degree of atrophy was mild to moderate in the PLDR group, but severe in the CRT group. The most pronounced morphological abnormalities were in the immune and hematopoietic systems, namely spleen and bone marrow. Brain hemorrhage was seen in the CRT group, but not in the PLDR group. Conclusions: Our results showed that PLDR induced less toxicity in the normal mouse tissues than conventional radiotherapy for the same dose and regimen. Considering that PLDR produces equivalent tumor control as conventional radiotherapy, it would be a good modality for treatment of recurrent cancers.

  5. Sexual Functioning Among Endometrial Cancer Patients Treated With Adjuvant High-Dose-Rate Intra-Vaginal Radiation Therapy

    SciTech Connect (OSTI)

    Damast, Shari; Alektiar, Kaled M.; Goldfarb, Shari; Eaton, Anne; Patil, Sujata; Mosenkis, Jeffrey; Bennett, Antonia; Atkinson, Thomas; Jewell, Elizabeth; Leitao, Mario; Barakat, Richard; Carter, Jeanne; Basch, Ethan

    2012-10-01

    Purpose: We used the Female Sexual Function Index (FSFI) to investigate the prevalence of sexual dysfunction (SD) and factors associated with diminished sexual functioning in early stage endometrial cancer (EC) patients treated with simple hysterectomy and adjuvant brachytherapy. Methods and Materials: A cohort of 104 patients followed in a radiation oncology clinic completed questionnaires to quantify current levels of sexual functioning. The time interval between hysterectomy and questionnaire completion ranged from <6 months to >5 years. Multivariate regression was performed using the FSFI as a continuous variable (score range, 1.2-35.4). SD was defined as an FSFI score of <26, based on the published validation study. Results: SD was reported by 81% of respondents. The mean ({+-} standard deviation) domain scores in order of highest-to-lowest functioning were: satisfaction, 2.9 ({+-}2.0); orgasm, 2.5 ({+-}2.4); desire, 2.4 ({+-}1.3); arousal, 2.2 ({+-}2.0); dryness, 2.1 ({+-}2.1); and pain, 1.9 ({+-}2.3). Compared to the index population in which the FSFI cut-score was validated (healthy women ages 18-74), all scores were low. Compared to published scores of a postmenopausal population, scores were not statistically different. Multivariate analysis isolated factors associated with lower FSFI scores, including having laparotomy as opposed to minimally invasive surgery (effect size, -7.1 points; 95% CI, -11.2 to -3.1; P<.001), lack of vaginal lubricant use (effect size, -4.4 points; 95% CI, -8.7 to -0.2, P=.040), and short time interval (<6 months) from hysterectomy to questionnaire completion (effect size, -4.6 points; 95% CI, -9.3-0.2; P=.059). Conclusions: The rate of SD, as defined by an FSFI score <26, was prevalent. The postmenopausal status of EC patients alone is a known risk factor for SD. Additional factors associated with poor sexual functioning following treatment for EC included receipt of laparotomy and lack of vaginal lubricant use.

  6. A Prospective Longitudinal Clinical Trial Evaluating Quality of Life After Breast-Conserving Surgery and High-Dose-Rate Interstitial Brachytherapy for Early-Stage Breast Cancer

    SciTech Connect (OSTI)

    Garsa, Adam A.; Ferraro, Daniel J.; DeWees, Todd A.; Deshields, Teresa L.; Margenthaler, Julie A.; Cyr, Amy E.; Naughton, Michael; Aft, Rebecca; Gillanders, William E.; Eberlein, Timothy; Matesa, Melissa A.; Ochoa, Laura L.; Zoberi, Imran

    2013-12-01

    Purpose: To prospectively examine quality of life (QOL) of patients with early stage breast cancer treated with accelerated partial breast irradiation (APBI) using high-dose-rate (HDR) interstitial brachytherapy. Methods and Materials: Between March 2004 and December 2008, 151 patients with early stage breast cancer were enrolled in a phase 2 prospective clinical trial. Eligible patients included those with Tis-T2 tumors measuring ?3 cm excised with negative surgical margins and with no nodal involvement. Patients received 3.4 Gy twice daily to a total dose of 34 Gy. QOL was measured using European Organization for Research and Treatment of Cancer (EORTC) QLQ-C30, version 3.0, and QLQ-BR23 questionnaires. The QLQ-C30 and QLQ-BR23 questionnaires were evaluated during pretreatment and then at 6 to 8 weeks, 3 to 4 months, 6 to 8 months, and 1 and 2 years after treatment. Results: The median follow-up was 55 months. Breast symptom scores remained stable in the months after treatment, and they significantly improved 6 to 8 months after treatment. Scores for emotional functioning, social functioning, and future perspective showed significant improvement 2 years after treatment. Symptomatic fat necrosis was associated with several changes in QOL, including increased pain, breast symptoms, systemic treatment side effects, dyspnea, and fatigue, as well as decreased role functioning, emotional functioning, and social functioning. Conclusions: HDR multicatheter interstitial brachytherapy was well tolerated, with no significant detrimental effect on measured QOL scales/items through 2 years of follow-up. Compared to pretreatment scores, there was improvement in breast symptoms, emotional functioning, social functioning, and future perspective 2 years after treatment.

  7. Direct 2-Arm Comparison Shows Benefit of High-Dose-Rate Brachytherapy Boost vs External Beam Radiation Therapy Alone for Prostate Cancer

    SciTech Connect (OSTI)

    Khor, Richard; Duchesne, Gillian; Monash University, Melbourne ; Tai, Keen-Hun; Foroudi, Farshad; Chander, Sarat; Van Dyk, Sylvia; Garth, Margaret; Williams, Scott

    2013-03-01

    Purpose: To evaluate the outcomes of patients treated for intermediate- and high-risk prostate cancer with a single schedule of either external beam radiation therapy (EBRT) and high-dose-rate brachytherapy (HDRB) boost or EBRT alone. Methods and Materials: From 2001-2006, 344 patients received EBRT with HDRB boost for definitive treatment of intermediate- or high-risk prostate cancer. The prescribed EBRT dose was 46 Gy in 23 fractions, with a HDR boost of 19.5 Gy in 3 fractions. This cohort was compared to a contemporaneously treated cohort who received EBRT to 74 Gy in 37 fractions, using a matched pair analysis. Three-dimensional conformal EBRT was used. Matching was performed using a propensity score matching technique. High-risk patients constituted 41% of the matched cohorts. Five-year clinical and biochemical outcomes were analyzed. Results: Initial significant differences in prognostic indicators between the unmatched treatment cohorts were rendered negligible after matching, providing a total of 688 patients. Median biochemical follow-up was 60.5 months. The 5-year freedom from biochemical failure was 79.8% (95% confidence interval [CI], 74.3%-85.0%) and 70.9% (95% CI, 65.4%-76.0%) for the HDRB and EBRT groups, respectively, equating to a hazard ratio of 0.59 (95% CI, 0.43-0.81, P=.0011). Interaction analyses showed no alteration in HDR efficacy when planned androgen deprivation therapy was administered (P=.95), but a strong trend toward reduced efficacy was shown compared to EBRT in high-risk cases (P=.06). Rates of grade 3 urethral stricture were 0.3% (95% CI, 0%-0.9%) and 11.8% (95% CI, 8.1%-16.5%) for EBRT and HDRB, respectively (P<.0001). No differences in clinical outcomes were observed. Conclusions: This comparison of 2 individual contemporaneously treated HDRB and EBRT approaches showed improved freedom from biochemical progression with the HDR approach. The benefit was more pronounced in intermediate- risk patients but needs to be weighed against an increased risk of urethral toxicity.

  8. Real-time catheter tracking for high-dose-rate prostate brachytherapy using an electromagnetic 3D-guidance device: A preliminary performance study

    SciTech Connect (OSTI)

    Zhou Jun; Sebastian, Evelyn; Mangona, Victor; Yan Di

    2013-02-15

    Purpose: In order to increase the accuracy and speed of catheter reconstruction in a high-dose-rate (HDR) prostate implant procedure, an automatic tracking system has been developed using an electromagnetic (EM) device (trakSTAR, Ascension Technology, VT). The performance of the system, including the accuracy and noise level with various tracking parameters and conditions, were investigated. Methods: A direct current (dc) EM transmitter (midrange model) and a sensor with diameter of 1.3 mm (Model 130) were used in the trakSTAR system for tracking catheter position during HDR prostate brachytherapy. Localization accuracy was assessed under both static and dynamic analyses conditions. For the static analysis, a calibration phantom was used to investigate error dependency on operating room (OR) table height (bottom vs midposition vs top), sensor position (distal tip of catheter vs connector end of catheter), direction [left-right (LR) vs anterior-posterior (AP) vs superior-inferior (SI)], sampling frequency (40 vs 80 vs 120 Hz), and interference from OR equipment (present vs absent). The mean and standard deviation of the localization offset in each direction and the corresponding error vectors were calculated. For dynamic analysis, the paths of five straight catheters were tracked to study the effects of directions, sampling frequency, and interference of EM field. Statistical analysis was conducted to compare the results in different configurations. Results: When interference was present in the static analysis, the error vectors were significantly higher at the top table position (3.3 {+-} 1.3 vs 1.8 {+-} 0.9 mm at bottom and 1.7 {+-} 1.0 mm at middle, p < 0.001), at catheter end position (3.1 {+-} 1.1 vs 1.4 {+-} 0.7 mm at the tip position, p < 0.001), and at 40 Hz sampling frequency (2.6 {+-} 1.1 vs 2.4 {+-} 1.5 mm at 80 Hz and 1.8 {+-} 1.1 at 160 Hz, p < 0.001). So did the mean offset errors in the LR direction (-1.7 {+-} 1.4 vs 0.4 {+-} 0.5 mm in AP and 0.8 {+-} 0.8 mm in SI directions, p < 0.001). The error vectors were significantly higher with surrounding interference (2.2 {+-} 1.3 mm) vs without interference (1.0 {+-} 0.7 mm, p < 0.001). An accuracy of 1.6 {+-} 0.2 mm can be reached when using optimum configuration (160 Hz at middle table position). When interference was present in the dynamic tracking, the mean tracking errors in LR direction (1.4 {+-} 0.5 mm) was significantly higher than that in AP direction (0.3 {+-} 0.2 mm, p < 0.001). So did the mean vector errors at 40 Hz (2.1 {+-} 0.2 mm vs 1.3 {+-} 0.2 mm at 80 Hz and 0.9 {+-} 0.2 mm at 160 Hz, p < 0.05). However, when interference was absent, they were comparable in the both directions and at all sampling frequencies. An accuracy of 0.9 {+-} 0.2 mm was obtained for the dynamic tracking when using optimum configuration. Conclusions: The performance of an EM tracking system depends highly on the system configuration and surrounding environment. The accuracy of EM tracking for catheter reconstruction in a prostate HDR brachytherapy procedure can be improved by reducing interference from surrounding equipment, decreasing distance from transmitter to tracking area, and choosing appropriated sampling frequency. A calibration scheme is needed to further reduce the tracking error when the interference is high.

  9. WE-A-17A-03: Catheter Digitization in High-Dose-Rate Brachytherapy with the Assistance of An Electromagnetic (EM) Tracking System

    SciTech Connect (OSTI)

    Damato, AL; Bhagwat, MS; Buzurovic, I; Devlin, PM; Friesen, S; Hansen, JL; Kapur, T; Lee, LJ; Mehrtash, A; Nguyen, PL; O'Farrell, D; Wang, W; Viswanathan, AN; Cormack, RA

    2014-06-15

    Purpose: To investigate the use of a system using EM tracking, postprocessing and error-detection algorithms for measuring brachytherapy catheter locations and for detecting errors and resolving uncertainties in treatment-planning catheter digitization. Methods: An EM tracker was used to localize 13 catheters in a clinical surface applicator (A) and 15 catheters inserted into a phantom (B). Two pairs of catheters in (B) crossed paths at a distance <2 mm, producing an undistinguishable catheter artifact in that location. EM data was post-processed for noise reduction and reformatted to provide the dwell location configuration. CT-based digitization was automatically extracted from the brachytherapy plan DICOM files (CT). EM dwell digitization error was characterized in terms of the average and maximum distance between corresponding EM and CT dwells per catheter. The error detection rate (detected errors / all errors) was calculated for 3 types of errors: swap of two catheter numbers; incorrect catheter number identification superior to the closest position between two catheters (mix); and catheter-tip shift. Results: The averages 1 standard deviation of the average and maximum registration error per catheter were 1.90.7 mm and 3.01.1 mm for (A) and 1.60.6 mm and 2.70.8 mm for (B). The error detection rate was 100% (A and B) for swap errors, mix errors, and shift >4.5 mm (A) and >5.5 mm (B); errors were detected for shifts on average >2.0 mm (A) and >2.4 mm (B). Both mix errors associated with undistinguishable catheter artifacts were detected and at least one of the involved catheters was identified. Conclusion: We demonstrated the use of an EM tracking system for localization of brachytherapy catheters, detection of digitization errors and resolution of undistinguishable catheter artifacts. Automatic digitization may be possible with a registration between the imaging and the EM frame of reference. Research funded by the Kaye Family Award 2012.

  10. Initial Beta-Gamma Nuclear Detector Background Study

    SciTech Connect (OSTI)

    Cooper, Matthew W.; Aalseth, Craig E.; Haas, Derek A.; Hayes, James C.

    2011-09-12

    Detection of underground nuclear explosions and, more recently, nuclear reactor events is of great national interest. These measurements are most often made by determining the concentration of radioactive noble gases in the atmosphere. Currently there are several ground-based systems capable of making radioxenon gas measurements. The measurement is often close to the detection limit, so understanding the parameters and features that limit the measurement is very important. A preliminary study of the detection limit has been performed using a ?-? Quad detector designed at Pacific Northwest National Laboratory (PNNL). The initial study has concentrated on the measuring the ambient radioactive background. By making several background measurements while varying the detector, shielding it is possible to identify whether the ambient background is internal or external to the detector. Furthermore, internal background contributions can be potentially reduced by selecting alternative low-background materials, while external background can be reduced by increasing the active or passive shielding present. By reducing the background contributions, it is possible to improve the detection limit and therefore the likelihood of positively identifying a nuclear test.

  11. Estimate Radiological Dose for Animals

    Energy Science and Technology Software Center (OSTI)

    1997-12-18

    Estimate Radiological dose for animals in ecological environment using open literature values for parameters such as body weight, plant and soil ingestion rate, rad. halflife, absorbed energy, biological halflife, gamma energy per decay, soil-to-plant transfer factor, ...etc

  12. Microsoft PowerPoint - Low Dose Update Metting 6 Dec 2012

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

    doses, HZE particles) * NCI (National Cancer Institute) focuses on patient health from ... shown * A pronounced dose-rate effect for cancer * Strong low dose "sparing" effect * Data ...

  13. Low Dose Radiation

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

    Ancient Salt Beds Repository Science Renewable Energy The WIPP Underground may be ideal to study effects of Very Low Dose Rates on Biological Systems Low Background Radiation Experiment We're all bathing in it. It's in the food we eat, the water we drink, the soil we tread and even the air we breathe. It's background radiation, it's everywhere and we can't get away from it. But what would happen if you somehow "pulled the plug" on natural background radiation? Would organisms suffer or

  14. Low Dose Suppression of Neoplastic Transformation in Vitro

    SciTech Connect (OSTI)

    John Leslie Redpath

    2012-05-01

    This grant was to study the low dose suppression of neoplastic transformation in vitro and the shape of the dose-response curve at low doses and dose-rates of ionizing radiation. Previous findings had indicated a suppression of transformation at dose <10cGy of low-LET radiation when delivered at high dose-rate. The present study indicates that such suppression extends out to doses in excess of 100cGy when the dose (from I-125 photons) is delivered at dose-rates as low as 0.2 mGy/min and out to in excess of {approx}25cGy the highest dose studied at the very low dose-rate of 0.5 mGy/day. We also examined dose-rate effects for high energy protons (which are a low-LET radiation) and suppression was evident below {approx}10cGy for high dose-rate delivery and at least out to 50cGy for low dose-rate (20cGy/h) delivery. Finally, we also examined the effect of low doses of 1 GeV/n iron ions (a high-LET radiation) delivered at high dose-rate on transformation at low doses and found a suppression below {approx}10cGy that could be attributable to an adaptive response in bystander cells induced by the associated low-LET delta rays. These results have implications for cancer risk assessment at low doses.

  15. Rate Information

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

    links Financial Information Financial Public Processes Asset Management Cost Verification Process Rate Cases Rate Information Current Power Rates Current Transmission Rates...

  16. Toward Dose Optimization for Fractionated Stereotactic Radiotherapy for Acoustic Neuromas: Comparison of Two Dose Cohorts

    SciTech Connect (OSTI)

    Andrews, David W. Werner-Wasik, Maria; Den, Robert B.; Paek, Sun Ha; Downes-Phillips, Beverly; Willcox, Thomas O.; Bednarz, Greg; Maltenfort, Mitchel; Evans, James J.; Curran, Walter J.

    2009-06-01

    Purpose: To describe our initial experience of fractionated stereotactic radiotherapy dose reduction comparing two dose cohorts with examination of tumor control rates and serviceable hearing preservation rates. Methods and Materials: After institutional review board approval, we initiated a retrospective chart review to study the hearing outcomes and tumor control rates. All data were entered into a JMP, version 7.01, statistical spreadsheet for analysis. Results: A total of 89 patients with serviceable hearing had complete serial audiometric data available for analysis. The higher dose cohort included 43 patients treated to 50.4 Gy with a median follow-up (latest audiogram) of 53 weeks and the lower dose cohort included 46 patients treated to 46.8 Gy with a median follow-up of 65 weeks. The tumor control rate was 100% in both cohorts, and the pure tone average was significantly improved in the low-dose cohort (33 dB vs. 40 dB, p = 0.023, chi-square). When the patient data were analyzed at comparable follow-up points, the actuarial hearing preservation rate was significantly longer for the low-dose cohort than for the high-dose cohort (165 weeks vs. 79 weeks, p = .0318, log-rank). Multivariate analysis revealed the dose cohort (p = 0.0282) and pretreatment Gardner-Robertson class (p = 0.0215) to be highly significant variables affecting the hearing outcome. Conclusion: A lower total dose at 46.8 Gy was associated with a 100% local control tumor rate and a greater hearing preservation rate. An additional dose reduction is justified to achieve the optimal dose that will yield the greatest hearing preservation rate without compromising tumor control for these patients.

  17. B-Plant D-Filter detector system qualification test report

    SciTech Connect (OSTI)

    Ritter, G.A., Westinghouse Hanford

    1996-08-23

    This report summarizes the results of qualification testing of the B Plant D-Filter Detector System. The purpose of this test was to verify that the system meets the performance requirements and that the unit is ready for field deployment. Testing was performed in the test pit in the 306E Facility. This detector system will be deployed in the B Plant D-Filter to measure beta/gamma dose rates from the filter bank.

  18. Rate Schedules

    Broader source: Energy.gov [DOE]

    One of the major responsibilities of Southeastern is to design, formulate, and justify rate schedules. Repayment studies prepared by the agency determine revenue requirements and appropriate rate...

  19. Enjebi Island dose assessment

    SciTech Connect (OSTI)

    Robison, W.L.; Conrado, C.L.; Phillips, W.A.

    1987-07-01

    We have updeated the radiological dose assessment for Enjebi Island at Enewetak Atoll using data derived from analysis of food crops grown on Enjebi. This is a much more precise assessment of potential doses to people resettling Enjebi Island than the 1980 assessment in which there were no data available from food crops on Enjebi. Details of the methods and data used to evaluate each exposure pathway are presented. The terrestrial food chain is the most significant potential exposure pathway and /sup 137/Cs is the radionuclide responsible for most of the estimated dose over the next 50 y. The doses are calculated assuming a resettlement date of 1990. The average wholebody maximum annual estimated dose equivalent derived using our diet model is 166 mremy;the effective dose equivalent is 169 mremy. The estimated 30-, 50-, and 70-y integral whole-body dose equivalents are 3.5 rem, 5.1 rem, and 6.2 rem, respectively. Bone-marrow dose equivalents are only slightly higher than the whole-body estimates in each case. The bone-surface cells (endosteal cells) receive the highest dose, but they are a less sensitive cell population and are less sensitive to fatal cancer induction than whole body and bone marrow. The effective dose equivalents for 30, 50, and 70 y are 3.6 rem, 5.3 rem, and 6.6 rem, respectively. 79 refs., 17 figs., 24 tabs

  20. Neutron dose equivalent meter

    DOE Patents [OSTI]

    Olsher, Richard H. (Los Alamos, NM); Hsu, Hsiao-Hua (Los Alamos, NM); Casson, William H. (Los Alamos, NM); Vasilik, Dennis G. (Los Alamos, NM); Kleck, Jeffrey H. (Menlo Park, CA); Beverding, Anthony (Foster City, CA)

    1996-01-01

    A neutron dose equivalent detector for measuring neutron dose capable of accurately responding to neutron energies according to published fluence to dose curves. The neutron dose equivalent meter has an inner sphere of polyethylene, with a middle shell overlying the inner sphere, the middle shell comprising RTV.RTM. silicone (organosiloxane) loaded with boron. An outer shell overlies the middle shell and comprises polyethylene loaded with tungsten. The neutron dose equivalent meter defines a channel through the outer shell, the middle shell, and the inner sphere for accepting a neutron counter tube. The outer shell is loaded with tungsten to provide neutron generation, increasing the neutron dose equivalent meter's response sensitivity above 8 MeV.

  1. Finance & Rates

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

    all of its costs in the rates it charges customers for wholesale electricity and transmission services. The agency is committed to careful cost management consistent with its...

  2. Derivation of dose conversion factors for tritium

    SciTech Connect (OSTI)

    Killough, G. G.

    1982-03-01

    For a given intake mode (ingestion, inhalation, absorption through the skin), a dose conversion factor (DCF) is the committed dose equivalent to a specified organ of an individual per unit intake of a radionuclide. One also may consider the effective dose commitment per unit intake, which is a weighted average of organ-specific DCFs, with weights proportional to risks associated with stochastic radiation-induced fatal health effects, as defined by Publication 26 of the International Commission on Radiological Protection (ICRP). This report derives and tabulates organ-specific dose conversion factors and the effective dose commitment per unit intake of tritium. These factors are based on a steady-state model of hydrogen in the tissues of ICRP's Reference Man (ICRP Publication 23) and equilibrium of specific activities between body water and other tissues. The results differ by 27 to 33% from the estimate on which ICRP Publication 30 recommendations are based. The report also examines a dynamic model of tritium retention in body water, mineral bone, and two compartments representing organically-bound hydrogen. This model is compared with data from human subjects who were observed for extended periods. The manner of combining the dose conversion factors with measured or model-predicted levels of contamination in man's exposure media (air, drinking water, soil moisture) to estimate dose rate to an individual is briefly discussed.

  3. Revised RTG source term and dose rate shielding evaluation

    SciTech Connect (OSTI)

    Goldberg, H.J., Westinghouse Hanford

    1996-07-31

    A source term was developed for the RTG and the adequacy with regards to shielding of the shipping container in which it will be transported was evaluated.

  4. Dose Rate Calculation of TRU Metal Ingot in Pyroprocessing - 12202

    SciTech Connect (OSTI)

    Lee, Yoon Hee; Lee, Kunjai

    2012-07-01

    Spent fuel management has been a main problem to be solved for continuous utilization of nuclear energy. Spent fuel management policy of Korea is 'Wait and See'. It is focused on Pyro-process and SFR (Sodium-cooled Fast Reactor) for closed-fuel cycle research and development in Korea. For peaceful use of nuclear facilities, the proliferation resistance has to be proved. Proliferation resistance is one of key constraints in the deployment of advanced nuclear energy systems. Non-proliferation and safeguard issues have been strengthening internationally. Barriers to proliferation are that reduces desirability or attractiveness as an explosive and makes it difficult to gain access to the materials, or makes it difficult to misuse facilities and/or technologies for weapons applications. Barriers to proliferation are classified into intrinsic and extrinsic barriers. Intrinsic barrier is inherent quality of reactor materials or the fuel cycle that is built into the reactor design and operation such as material and technical barriers. As one of the intrinsic measures, the radiation from the material is considered significantly. Therefore the radiation of TRU metal ingot from the pyro-process was calculated using ORIGEN and MCNP code. (authors)

  5. Imaging method for monitoring delivery of high dose rate brachytherapy

    DOE Patents [OSTI]

    Weisenberger, Andrew G; Majewski, Stanislaw

    2012-10-23

    A method for in-situ monitoring both the balloon/cavity and the radioactive source in brachytherapy treatment utilizing using at least one pair of miniature gamma cameras to acquire separate images of: 1) the radioactive source as it is moved in the tumor volume during brachytherapy; and 2) a relatively low intensity radiation source produced by either an injected radiopharmaceutical rendering cancerous tissue visible or from a radioactive solution filling a balloon surgically implanted into the cavity formed by the surgical resection of a tumor.

  6. Apparatus and method for high dose rate brachytherapy radiation treatment

    DOE Patents [OSTI]

    Macey, Daniel J.; Majewski, Stanislaw; Weisenberger, Andrew G.; Smith, Mark Frederick; Kross, Brian James

    2005-01-25

    A method and apparatus for the in vivo location and tracking of a radioactive seed source during and after brachytherapy treatment. The method comprises obtaining multiple views of the seed source in a living organism using: 1) a single PSPMT detector that is exposed through a multiplicity of pinholes thereby obtaining a plurality of images from a single angle; 2) a single PSPMT detector that may obtain an image through a single pinhole or a plurality of pinholes from a plurality of angles through movement of the detector; or 3) a plurality of PSPMT detectors that obtain a plurality of views from different angles simultaneously or virtually simultaneously. The plurality of images obtained from these various techniques, through angular displacement of the various acquired images, provide the information required to generate the three dimensional images needed to define the location of the radioactive seed source within the body of the living organism.

  7. Dose Calculation Spreadsheet

    Energy Science and Technology Software Center (OSTI)

    1997-06-10

    VENTSAR XL is an EXCEL Spreadsheet that can be used to calculate downwind doses as a result of a hypothetical atmospheric release. Both building effects and plume rise may be considered. VENTSAR XL will run using any version of Microsoft EXCEL version 4.0 or later. Macros (the programming language of EXCEL) was used to automate the calculations. The user enters a minimal amount of input and the code calculates the resulting concentrations and doses atmore » various downwind distances as specified by the user.« less

  8. LADTAPXL Aqueous Dose Spreadsheet

    Energy Science and Technology Software Center (OSTI)

    1999-08-10

    LADTAPXL is an EXCEL spreadsheet model of the NRC computer code LADTAP. LADTAPXL calculates maximally exposed individual and population doses from chronic liquid releases. Environmental pathways include external exposure resulting from recreational activities on the Savannah River and ingestion of water, fish, and invertebrates of Savannah River origin.

  9. Existing Data Format for Two-Parameter Beta-Gamma Histograms...

    Office of Scientific and Technical Information (OSTI)

    includes spectral information from gamma-rays and betasconversion electrons. It is worth noting that the betaconversion electron energy information will be used to separate...

  10. Existing Data Format for Two-Parameter Beta-Gamma Histograms...

    Office of Scientific and Technical Information (OSTI)

    radioxenons. 2) The RMS data format assumes that the conversion between counts and activity can be calculated based (in part) more on a simple calibration curve (detector...

  11. Estimating Radiation Risk from Total Effective Dose Equivalent (TEDE) ISCORS Technical Report No. 1

    National Nuclear Security Administration (NNSA)

    and UNSCEAR 1988 in Radiation Risk Assessment - Lifetime Total Cancer Mortality Risk Estimates at Low Doses and Low Dose Rates for Low-LET Radiation, Committee on Interagency Radiation Research and Policy Coordination, December 1992. DOE, 1988a. E xternal Dose-Rate Conversion Factors for Calculation of Dose to the Public, DOE Report DOE/EH-0070, July 1988. DOE, 1988b. Internal Dose Conversion Factors for Calculation of Dose to the Public, DOE Report DOE/EH-0071, July 1988. EPA, 1988. Federal

  12. Rates Meetings and Workshops (pbl/rates)

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

    Rate Case Workshops Other Power Rates-Related Workshops July 1, 2004 - Rates and Finances Workshop (updated June 25, 2004) (financial and rate forecasts and scenarios for FY...

  13. Agriculture-related radiation dose calculations

    SciTech Connect (OSTI)

    Furr, J.M.; Mayberry, J.J.; Waite, D.A.

    1987-10-01

    Estimates of radiation dose to the public must be made at each stage in the identification and qualification process leading to siting a high-level nuclear waste repository. Specifically considering the ingestion pathway, this paper examines questions of reliability and adequacy of dose calculations in relation to five stages of data availability (geologic province, region, area, location, and mass balance) and three methods of calculation (population, population/food production, and food production driven). Calculations were done using the model PABLM with data for the Permian and Palo Duro Basins and the Deaf Smith County area. Extra effort expended in gathering agricultural data at succeeding environmental characterization levels does not appear justified, since dose estimates do not differ greatly; that effort would be better spent determining usage of food types that contribute most to the total dose; and that consumption rate and the air dispersion factor are critical to assessment of radiation dose via the ingestion pathway. 17 refs., 9 figs., 32 tabs.

  14. Hanford Environmental Dose Reconstruction Project

    SciTech Connect (OSTI)

    Cannon, S.D.; Finch, S.M.

    1992-10-01

    The objective of the Hanford Environmental Dose Reconstruction (HEDR) Project is to estimate the radiation doses that individuals and populations could have received from nuclear operations at Hanford since 1944. The independent Technical Steering Panel (TSP) provides technical direction. The project is divided into the following technical tasks. These tasks correspond to the path radionuclides followed from release to impact on humans (dose estimates):Source Terms, Environmental Transport, Environmental Monitoring Data, Demography, Food Consumption, and Agriculture, and Environmental Pathways and Dose Estimates.

  15. ORISE: Dose modeling and assessments

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

    Dose modeling and assessments The Oak Ridge Institute for Science and Education (ORISE) offers dose modeling and assessment services to demonstrate that federal and/or state regulatory compliance requirements are being met during the decontamination and decommissioning of nuclear facilities. Dose modeling is an important step in the assessment of safety and regulatory compliance, as well as the development of standards and regulatory rulemaking. The ultimate goal of dose modeling and assessments

  16. Shared dosimetry error in epidemiological dose-response analyses

    SciTech Connect (OSTI)

    Stram, Daniel O.; Preston, Dale L.; Sokolnikov, Mikhail; Napier, Bruce; Kopecky, Kenneth J.; Boice, John; Beck, Harold; Till, John; Bouville, Andre; Zeeb, Hajo

    2015-03-23

    Radiation dose reconstruction systems for large-scale epidemiological studies are sophisticated both in providing estimates of dose and in representing dosimetry uncertainty. For example, a computer program was used by the Hanford Thyroid Disease Study to provide 100 realizations of possible dose to study participants. The variation in realizations reflected the range of possible dose for each cohort member consistent with the data on dose determinates in the cohort. Another example is the Mayak Worker Dosimetry System 2013 which estimates both external and internal exposures and provides multiple realizations of "possible" dose history to workers given dose determinants. This paper takes up the problem of dealing with complex dosimetry systems that provide multiple realizations of dose in an epidemiologic analysis. In this paper we derive expected scores and the information matrix for a model used widely in radiation epidemiology, namely the linear excess relative risk (ERR) model that allows for a linear dose response (risk in relation to radiation) and distinguishes between modifiers of background rates and of the excess risk due to exposure. We show that treating the mean dose for each individual (calculated by averaging over the realizations) as if it was true dose (ignoring both shared and unshared dosimetry errors) gives asymptotically unbiased estimates (i.e. the score has expectation zero) and valid tests of the null hypothesis that the ERR slope ? is zero. Although the score is unbiased the information matrix (and hence the standard errors of the estimate of ?) is biased for ??0 when ignoring errors in dose estimates, and we show how to adjust the information matrix to remove this bias, using the multiple realizations of dose. The use of these methods in the context of several studies including, the Mayak Worker Cohort, and the U.S. Atomic Veterans Study, is discussed.

  17. Shared dosimetry error in epidemiological dose-response analyses

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

    Stram, Daniel O.; Preston, Dale L.; Sokolnikov, Mikhail; Napier, Bruce; Kopecky, Kenneth J.; Boice, John; Beck, Harold; Till, John; Bouville, Andre; Zeeb, Hajo

    2015-03-23

    Radiation dose reconstruction systems for large-scale epidemiological studies are sophisticated both in providing estimates of dose and in representing dosimetry uncertainty. For example, a computer program was used by the Hanford Thyroid Disease Study to provide 100 realizations of possible dose to study participants. The variation in realizations reflected the range of possible dose for each cohort member consistent with the data on dose determinates in the cohort. Another example is the Mayak Worker Dosimetry System 2013 which estimates both external and internal exposures and provides multiple realizations of "possible" dose history to workers given dose determinants. This paper takesmore » up the problem of dealing with complex dosimetry systems that provide multiple realizations of dose in an epidemiologic analysis. In this paper we derive expected scores and the information matrix for a model used widely in radiation epidemiology, namely the linear excess relative risk (ERR) model that allows for a linear dose response (risk in relation to radiation) and distinguishes between modifiers of background rates and of the excess risk due to exposure. We show that treating the mean dose for each individual (calculated by averaging over the realizations) as if it was true dose (ignoring both shared and unshared dosimetry errors) gives asymptotically unbiased estimates (i.e. the score has expectation zero) and valid tests of the null hypothesis that the ERR slope β is zero. Although the score is unbiased the information matrix (and hence the standard errors of the estimate of β) is biased for β≠0 when ignoring errors in dose estimates, and we show how to adjust the information matrix to remove this bias, using the multiple realizations of dose. The use of these methods in the context of several studies including, the Mayak Worker Cohort, and the U.S. Atomic Veterans Study, is discussed.« less

  18. Standardized radiological dose evaluations

    SciTech Connect (OSTI)

    Peterson, V.L.; Stahlnecker, E.

    1996-05-01

    Following the end of the Cold War, the mission of Rocky Flats Environmental Technology Site changed from production of nuclear weapons to cleanup. Authorization baseis documents for the facilities, primarily the Final Safety Analysis Reports, are being replaced with new ones in which accident scenarios are sorted into coarse bins of consequence and frequency, similar to the approach of DOE-STD-3011-94. Because this binning does not require high precision, a standardized approach for radiological dose evaluations is taken for all the facilities at the site. This is done through a standard calculation ``template`` for use by all safety analysts preparing the new documents. This report describes this template and its use.

  19. SU-E-T-315: The Change of Optically Stimulated Luminescent Dosimeters (OSLDs) Sensitivity by Accumulated Dose and High Dose

    SciTech Connect (OSTI)

    Han, S; Jung, H; Kim, M; Ji, Y; Kim, K [University of Science and Technology, Daejeon (Korea, Republic of); Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of); Choi, S; Park, S; Yoo, H [Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of); Yi, C [Korea Research Institute of Standards and Science, Daejeon (Korea, Republic of)

    2014-06-01

    Purpose: The objective of this study is to evaluate radiation sensitivity of optical stimulated luminance dosimeters (OSLDs) by accumulated dose and high dose. Methods: This study was carried out in Co-60 unit (Theratron 780, AECL, and Canada) and used InLight MicroStar reader (Landauer, Inc., Glenwood, IL) for reading. We annealed for 30 min using optical annealing system which contained fluorescent lamps (Osram lumilux, 24 W, 280 ?780 nm). To evaluate change of OSLDs sensitivity by repeated irradiation, the dosimeters were repeatedly irradiated with 1 Gy. And whenever a repeated irradiation, we evaluated OSLDs sensitivity. To evaluate OSLDs sensitivity after accumulated dose with 5 Gy, We irradiated dose accumulatively (from 1 Gy to 5 Gy) without annealing. And OSLDs was also irradiated with 15, 20, 30 Gy to certify change of OSLDs sensitivity after high dose irradiation. After annealing them, they were irradiated with 1Gy, repeatedly. Results: The OSLDs sensitivity increased up to 3% during irradiating seven times and decreased continuously above 8 times. That dropped by about 0.35 Gy per an irradiation. Finally, after 30 times irradiation, OSLDs sensitivity decreased by about 7%. For accumulated dose from 1 Gy to 5 Gy, OSLDs sensitivity about 1 Gy increased until 4.4% after second times accumulated dose compared with before that. OSLDs sensitivity about 1 Gy decreased by 1.6% in five times irradiation. When OSLDs were irradiated ten times with 1Gy after irradiating high dose (10, 15, 20 Gy), OSLDs sensitivity decreased until 6%, 9%, 12% compared with it before high dose irradiation, respectively. Conclusion: This study certified OSLDs sensitivity by accumulated dose and high dose. When irradiated with 1Gy, repeatedly, OSLDs sensitivity decreased linearly and the reduction rate of OSLDs sensitivity after high dose irradiation had dependence on irradiated dose.

  20. DOSE ASSESSMENT OF THE FINAL INVENTORIES IN CENTER SLIT TRENCHES ONE THROUGH FIVE

    SciTech Connect (OSTI)

    Collard, L.; Hamm, L.; Smith, F.

    2011-05-02

    In response to a request from Solid Waste Management (SWM), this study evaluates the performance of waste disposed in Slit Trenches 1-5 by calculating exposure doses and concentrations. As of 8/19/2010, Slit Trenches 1-5 have been filled and are closed to future waste disposal in support of an ARRA-funded interim operational cover project. Slit Trenches 6 and 7 are currently in operation and are not addressed within this analysis. Their current inventory limits are based on the 2008 SA and are not being impacted by this study. This analysis considers the location and the timing of waste disposal in Slit Trenches 1-5 throughout their operational life. In addition, the following improvements to the modeling approach have been incorporated into this analysis: (1) Final waste inventories from WITS are used for the base case analysis where variance in the reported final disposal inventories is addressed through a sensitivity analysis; (2) Updated K{sub d} values are used; (3) Area percentages of non-crushable containers are used in the analysis to determine expected infiltration flows for cases that consider collapse of these containers; (4) An updated representation of ETF carbon column vessels disposed in SLIT3-Unit F is used. Preliminary analyses indicated a problem meeting the groundwater beta-gamma dose limit because of high H-3 and I-129 release from the ETF vessels. The updated model uses results from a recent structural analysis of the ETF vessels indicating that water does not penetrate the vessels for about 130 years and that the vessels remain structurally intact throughout the 1130-year period of assessment; and (5) Operational covers are included with revised installation dates and sets of Slit Trenches that have a common cover. With the exception of the modeling enhancements noted above, the analysis follows the same methodology used in the 2008 PA (WSRC, 2008) and the 2008 SA (Collard and Hamm, 2008). Infiltration flows through the vadose zone are identical to the flows used in the 2008 PA, except for flows during the operational cover time period. The physical (i.e., non-geochemical) models of the vadose zone and aquifer are identical in most cases to the models used in the 2008 PA. However, the 2008 PA assumed a uniform distribution of waste within each Slit Trench (WITS Location) and assumed that the entire inventory of each trench was disposed of at the time the first Slit Trench was opened. The current analysis considers individual trench excavations (i.e., segments) and groups of segments (i.e., Inventory Groups also known as WITS Units) within Slit Trenches. Waste disposal is assumed to be spatially uniform in each Inventory Group and is distributed in time increments of six months or less between the time the Inventory Group was opened and closed.

  1. Current BPA Power Rates (pbl/rates)

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

    and Workshops WP-10 Rate Case WP-07 Rate Case WP-07 Supplemental Rate Case ASC Methodology Adjustments (2007-2009) Adjustments (2002-2006) Previous Rate Cases Financial...

  2. Power Rates Announcements (pbl/rates)

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

    WP-10 Rate Case WP-07 Rate Case WP-07 Supplemental Rate Case ASC Methodology Adjustments (2007-2009) Adjustments (2002-2006) Previous Rate Cases Financial Choices (2003-06) Power...

  3. Dose Coefficients | Department of Energy

    Office of Environmental Management (EM)

    Coefficients Dose Coefficients (Question Posted to ERAD in May 2012) Will DOE develop its own dose coefficients separate from, but based on ICRP 72 and other listed references? This question was answered during the ERAD call by Carlos Corredor: Yes, DOE has developed its own dose coefficients and was published in 2011 as DOE-STD-1196-2011, Derived Concentration Technical Standard. Prior to this Technical Standard, derived concentration standards (DCS) were last published by DOE in 1993 in

  4. ORISE: Dose modeling and assessments

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

    The Oak Ridge Institute for Science and Education (ORISE) offers dose modeling and assessment services to demonstrate that federal andor state regulatory compliance requirements...

  5. Current Power Rates

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

    links Financial Information Financial Public Processes Asset Management Cost Verification Process Rate Cases Rate Information Current Power Rates Current Transmission Rates...

  6. Current Transmission Rates

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

    links Financial Information Financial Public Processes Asset Management Cost Verification Process Rate Cases Rate Information Current Power Rates Current Transmission Rates...

  7. Previous Power Rates

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

    links Financial Information Financial Public Processes Asset Management Cost Verification Process Rate Cases Rate Information Current Power Rates Current Transmission Rates...

  8. Previous Transmission Rates

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

    links Financial Information Financial Public Processes Asset Management Cost Verification Process Rate Cases Rate Information Current Power Rates Current Transmission Rates...

  9. Wide-range radiation dose monitor

    DOE Patents [OSTI]

    Kopp, M.K.

    1984-09-20

    A radiation dose-rate monitor is provided which operates in a conventional linear mode for radiation in the 0 to 0.5 R/h range and utilizes a nonlinear mode of operation for sensing radiation from 0.5 R/h to over 500 R/h. The nonlinear mode is achieved by a feedback circuit which adjusts the high voltage bias of the proportional counter, and hence its gas gain, in accordance with the amount of radiation being monitored. This allows compression of readout onto a single scale over the range of 0 to greater than 500 R/h without scale switching operations.

  10. Wide-range radiation dose monitor

    DOE Patents [OSTI]

    Kopp, Manfred K.

    1986-01-01

    A radiation dose-rate monitor is provided which operates in a conventional linear mode for radiation in the 0 to 0.5 R/h range and utilizes a nonlinear mode of operation for sensing radiation from 0.5 R/h to over 500 R/h. The nonlinear mode is achieved by a feedback circuit which adjusts the high voltage bias of the proportional counter, and hence its gas gain, in accordance with the amount of radiation being monitored. This allows compression of readout onto a single scale over the range of 0 to greater than 500 R/h without scale switching operations.

  11. PNCA-02 Rate Case (rates/ratecases)

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

    Proposed Adjustment to the Rate for Interchange Energy Imbalances Under the Pacific Northwest Coordination Agreement (PNCA-02 Rate Case) (updated on April 26, 2002) BPA has issued...

  12. Dose Limits | Department of Energy

    Office of Environmental Management (EM)

    Limits Dose Limits (Question Posted to ERAD in May 2012) Who do you define as a member of the public for the onsite MEI? This question implies that there may be more than one maximally exposed individual (MEI), one on-site and one off-site, when demonstrating compliance with the Public Dose Limit of DOE Order 458.1. Although all potential MEIs should be considered and documented, as well as the calculated doses and pathways considered, the intent of DOE Order 458.1 is in fact to ultimately

  13. Hanford Environmental Dose Reconstruction Project

    SciTech Connect (OSTI)

    McMakin, A.H.; Cannon, S.D.; Finch, S.M.

    1992-07-01

    The objective of the Hanford Environmental Dose Reconstruction (HEDR) Project is to estimate the radiation doses that individuals and populations could have received from nuclear operations at Hanford since 1944. The TSP consists of experts in environmental pathways, epidemiology, surface-water transport, ground-water transport, statistics, demography, agriculture, meteorology, nuclear engineering, radiation dosimetry, and cultural anthropology. Included are appointed technical members representing the states of Oregon, Washington, and Idaho, a representative of Native American tribes, and an individual representing the public. The project is divided into the following technical tasks. These tasks correspond to the path radionuclides followed from release to impact on humans (dose estimates): Source terms, environmental transport, environmental monitoring data, demography, food consumption, and agriculture, and environmental pathways and dose estimates. Progress is discussed.

  14. Weldon Spring historical dose estimate

    SciTech Connect (OSTI)

    Meshkov, N.; Benioff, P.; Wang, J.; Yuan, Y.

    1986-07-01

    This study was conducted to determine the estimated radiation doses that individuals in five nearby population groups and the general population in the surrounding area may have received as a consequence of activities at a uranium processing plant in Weldon Spring, Missouri. The study is retrospective and encompasses plant operations (1957-1966), cleanup (1967-1969), and maintenance (1969-1982). The dose estimates for members of the nearby population groups are as follows. Of the three periods considered, the largest doses to the general population in the surrounding area would have occurred during the plant operations period (1957-1966). Dose estimates for the cleanup (1967-1969) and maintenance (1969-1982) periods are negligible in comparison. Based on the monitoring data, if there was a person residing continually in a dwelling 1.2 km (0.75 mi) north of the plant, this person is estimated to have received an average of about 96 mrem/yr (ranging from 50 to 160 mrem/yr) above background during plant operations, whereas the dose to a nearby resident during later years is estimated to have been about 0.4 mrem/yr during cleanup and about 0.2 mrem/yr during the maintenance period. These values may be compared with the background dose in Missouri of 120 mrem/yr.

  15. Rate Case Elements

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

    Proceeding Rate Information Residential Exchange Program Surplus Power Sales Reports Rate Case Elements BPA's rate cases are decided "on the record." That is, in making a decision...

  16. Power Rate Cases (pbl/rates)

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

    Choices (2003-06) Power Function Review (PFR) Firstgov Power Rate Cases BPA's wholesale power rates are set to recover its costs and repay the U.S. Treasury for the Federal...

  17. Chlorite Dissolution Rates

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

    Carroll, Susan

    2013-07-01

    Spreadsheets provides measured chlorite rate data from 100 to 300C at elevated CO2. Spreadsheet includes derived rate equation.

  18. Chlorite Dissolution Rates

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

    Carroll, Susan

    Spreadsheets provides measured chlorite rate data from 100 to 300C at elevated CO2. Spreadsheet includes derived rate equation.

  19. Mechanisms of Low Dose Radio-Suppression of Genomic Instability

    SciTech Connect (OSTI)

    Engelward, Bevin P

    2009-09-16

    The major goal of this project is to contribute toward the elucidation of the impact of long term low dose radiation on genomic stability. We have created and characterized novel technologies for delivering long term low dose radiation to animals, and we have studied genomic stability by applying cutting edge molecular analysis technologies. Remarkably, we have found that a dose rate that is 300X higher than background radiation does not lead to any detectable genomic damage, nor is there any significant change in gene expression for genes pertinent to the DNA damage response. These results point to the critical importance of dose rate, rather than just total dose, when evaluating public health risks and when creating regulatory guidelines. In addition to these studies, we have also further developed a mouse model for quantifying cells that have undergone a large scale DNA sequence rearrangement via homologous recombination, and we have applied these mice in studies of both low dose radiation and space radiation. In addition to more traditional approaches for assessing genomic stability, we have also explored radiation and possible beneficial effects (adaptive response), long term effects (persistent effects) and effects on communication among cells (bystander effects), both in vitro and in vivo. In terms of the adaptive response, we have not observed any significant induction of an adaptive response following long term low dose radiation in vivo, delivered at 300X background. In terms of persistent and bystander effects, we have revealed evidence of a bystander effect in vivo and with researchers at and demonstrated for the first time the molecular mechanism by which cells remember radiation exposure. Understanding the underlying molecular mechanisms by which radiation can induce genomic instability is fundamental to our ability to assess the biological impact of low dose radiation. Finally, in a parallel set of studies we have explored the effects of heavy iron particle radiation on large scale sequence rearrangements and we have discovered tissue specific differences in sensitivity to homologous recombination. DOE support has given rise to critical new knowledge about the biological impact of low dose rate radiation and about the underlying mechanisms that govern genomic stability in response to radiation exposure. This work has spurred interest in radiation among MIT scientists, and has fostered ongoing research projects that will continue to contribute toward our understanding of the biological effects of low dose radiation exposure.

  20. BP-18 Rate Proceeding

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

    Skip navigation links Financial Information Financial Public Processes Asset Management Cost Verification Process Rate Cases BP-18 Rate Case Related Publications Meetings...

  1. BP-12 Rate Case

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

    Skip navigation links Financial Information Financial Public Processes Asset Management Cost Verification Process Rate Cases BP-18 Rate Case Related Publications Meetings...

  2. BP-16 Rate Case

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

    Skip navigation links Financial Information Financial Public Processes Asset Management Cost Verification Process Rate Cases BP-18 Rate Case Related Publications Meetings...

  3. Before a Rate Case

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

    links Financial Information Financial Public Processes Asset Management Cost Verification Process Rate Cases BP-18 Rate Case Related Publications Meetings and Workshops Customer...

  4. Rating Agency Reports

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

    Liabilities Financial Plan Financial Public Processes Asset Management Cost Verification Process Rate Cases Rate Information Residential Exchange Program Surplus Power Sales...

  5. 2012 Transmission Rate Schedules

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

    2014 Transmission, Ancillary, and Control Area Service Rate Schedules and General Rate Schedule Provisions (FY 2014-2015) October 2013 United States Department of Energy...

  6. Dose comparisons for mammographic systems

    SciTech Connect (OSTI)

    Speiser, R.C.; Zanrosso, E.M.; Jeromin, L.S.; Carlson, R.A.

    1986-09-01

    Dose estimates were made for Kodak Min-R screens combined with Kodak Min-R film and Kodak Ortho M film, both with and without a 5:1 Bucky grid; for standard xeroradiographic techniques in negative development mode; and for the new, higher sensitivity xeroradiographic process of the Xerox 175 System. The estimates were derived from exposure versus depth measurements in phantoms made of BR12 breast simulation material using thermoluminescent detectors. A molybdenum target source with molybdenum filtration, at a half-value layer of 0.37-mm Al, was used for the screen-film measurements. All xeroradiographic measurements were made with a tungsten target source with aluminum filtration at half-value layers of 1.5 to 1.56 mm Al. Mean glandular dose estimates for the Min-R screen/Ortho M film combination with Bucky grid and for the new xeroradiographic process were found to be similar. Dose reduction with the new xeroradiographic system was achieved through a more sensitive photoreceptor and more sensitive development, which also improved the unique imaging characteristics of xeroradiography.

  7. Intensity Modulated Radiation Therapy With Dose Painting to Treat Rhabdomyosarcoma

    SciTech Connect (OSTI)

    Yang, Joanna C.; Dharmarajan, Kavita V.; Wexler, Leonard H.; La Quaglia, Michael P.; Happersett, Laura; Wolden, Suzanne L.

    2012-11-01

    Purpose: To examine local control and patterns of failure in rhabdomyosarcoma patients treated with intensity modulated radiation therapy (RT) with dose painting (DP-IMRT). Patients and Methods: A total of 41 patients underwent DP-IMRT with chemotherapy for definitive treatment. Nineteen also underwent surgery with or without intraoperative RT. Fifty-six percent had alveolar histologic features. The median interval from beginning chemotherapy to RT was 17 weeks (range, 4-25). Very young children who underwent second-look procedures with or without intraoperative RT received reduced doses of 24-36 Gy in 1.4-1.8-Gy fractions. Young adults received 50.4 Gy to the primary tumor and lower doses of 36 Gy in 1.8-Gy fractions to at-risk lymph node chains. Results: With 22 months of median follow-up, the actuarial local control rate was 90%. Patients aged {<=}7 years who received reduced overall and fractional doses had 100% local control, and young adults had 79% (P=.07) local control. Three local failures were identified in young adults whose primary target volumes had received 50.4 Gy in 1.8-Gy fractions. Conclusions: DP-IMRT with lower fractional and cumulative doses is feasible for very young children after second-look procedures with or without intraoperative RT. DP-IMRT is also feasible in adolescents and young adults with aggressive disease who would benefit from prophylactic RT to high-risk lymph node chains, although dose escalation might be warranted for improved local control. With limited follow-up, it appears that DP-IMRT produces local control rates comparable to those of sequential IMRT in patients with rhabdomyosarcoma.

  8. Reassessment of the potential radiological doses for residents resettling Enewetak Atoll

    SciTech Connect (OSTI)

    Robison, W.L.; Phillips, W.A.; Mount, M.E.; Clegg, B.R.; Conrado, C.L.

    1980-10-30

    The purpose of this report is to refine the dose predictions, subsequent to the cleanup effort, for alternate living patterns proposed for resettlement of Enewetak Atoll. The most recent data developed from projects at Enewetak and Bikini Atolls for concentration and uptake of Cs, Sr, Pu, and Am were used in conjunction with recent dietary information and current dose models to predict annual dose rates and 30- and 50-y integral doses (dose commitments). The terrestrial food chain in the most significant exposure pathway - it contributes more than 50% of the total dose - and external gamma exposure is the second most significant pathway. Other pathways evaluated are the marine food chain, drinking water, and inhalation.

  9. 5400.5

    Office of Environmental Management (EM)

    IV-6 DOE 5400.5 2 - 8 - 9 0 Figure IV-1 Surface Contamination Guidelines 1/ As used in this table, dpm (disintegrations per minute) means the rate of emission by radioactive material as determined by correcting the counts per minute measured by an appropriate detector for background, efficiency, and geometric factors associated with the instrumentation. 2/ Where surface contamination by both alpha- and beta-gamma-emitting radionuclides exists, the limits established for alpha- and beta-gamma-

  10. Characterization of a MOSkin detector for in vivo skin dose measurements during interventional radiology procedures

    SciTech Connect (OSTI)

    Safari, M. J.; Wong, J. H. D.; Ng, K. H.; Jong, W. L.; Cutajar, D. L.; Rosenfeld, A. B.

    2015-05-15

    Purpose: The MOSkin is a MOSFET detector designed especially for skin dose measurements. This detector has been characterized for various factors affecting its response for megavoltage photon beams and has been used for patient dose measurements during radiotherapy procedures. However, the characteristics of this detector in kilovoltage photon beams and low dose ranges have not been studied. The purpose of this study was to characterize the MOSkin detector to determine its suitability for in vivo entrance skin dose measurements during interventional radiology procedures. Methods: The calibration and reproducibility of the MOSkin detector and its dependency on different radiation beam qualities were carried out using RQR standard radiation qualities in free-in-air geometry. Studies of the other characterization parameters, such as the dose linearity and dependency on exposure angle, field size, frame rate, depth-dose, and source-to-surface distance (SSD), were carried out using a solid water phantom under a clinical x-ray unit. Results: The MOSkin detector showed good reproducibility (94%) and dose linearity (99%) for the dose range of 2 to 213 cGy. The sensitivity did not significantly change with the variation of SSD (1%), field size (1%), frame rate (3%), or beam energy (5%). The detector angular dependence was within 5% over 360 and the dose recorded by the MOSkin detector in different depths of a solid water phantom was in good agreement with the Markus parallel plate ionization chamber to within 3%. Conclusions: The MOSkin detector proved to be reliable when exposed to different field sizes, SSDs, depths in solid water, dose rates, frame rates, and radiation incident angles within a clinical x-ray beam. The MOSkin detector with water equivalent depth equal to 0.07 mm is a suitable detector for in vivo skin dosimetry during interventional radiology procedures.

  11. Hanford Environmental Dose Reconstruction Project. Monthly report

    SciTech Connect (OSTI)

    Cannon, S.D.; Finch, S.M.

    1992-10-01

    The objective of the Hanford Environmental Dose Reconstruction (HEDR) Project is to estimate the radiation doses that individuals and populations could have received from nuclear operations at Hanford since 1944. The independent Technical Steering Panel (TSP) provides technical direction. The project is divided into the following technical tasks. These tasks correspond to the path radionuclides followed from release to impact on humans (dose estimates):Source Terms, Environmental Transport, Environmental Monitoring Data, Demography, Food Consumption, and Agriculture, and Environmental Pathways and Dose Estimates.

  12. Multicriteria optimization of the spatial dose distribution

    SciTech Connect (OSTI)

    Schlaefer, Alexander; Viulet, Tiberiu; Muacevic, Alexander; Frweger, Christoph

    2013-12-15

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

  13. Resonant thermonuclear reaction rate

    SciTech Connect (OSTI)

    Haubold, H.J.; Mathai, A.M.

    1986-08-01

    Basic physical principles for the resonant and nonresonant thermonuclear reaction rates are applied to find their standard representations for nuclear astrophysics. Closed-form representations for the resonant reaction rate are derived in terms of Meijer's G-italic-function. Analytic representations of the resonant and nonresonant nuclear reaction rates are compared and the appearance of Meijer's G-italic-function is discussed in physical terms.

  14. Improving Entrainment Rate Parameterization

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

    Entrainment Rate Parameterization For original submission and image(s), see ARM Research Highlights http://www.arm.gov/science/highlights/ Research Highlight Parameterization of entrainment rate is critical for improving representation of cloud- and convection-related processes in climate models; however, much remains unclear. This work seeks to improve understanding and parameterization of entrainment rate by use of aircraft observations and large-eddy simulations of shallow cumulus clouds over

  15. LCC Guidance Rates

    Broader source: Energy.gov [DOE]

    Notepad text file provides the LCC guidance rates in a numbered format for the various regions throughout the U.S.

  16. Draft Tiered Rate Methodology

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

    For Regional Dialogue Discussion Purposes Only Pre-Decisional Draft Tiered Rates Methodology March 7, 2008 Pre-decisional, Deliberative, For Discussion Purposes Only March 7,...

  17. Early Internal and External Dose Magnitude Estimation

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

    Internal and External Dose Estimation (initial version: 08/2008, current version: 10/2015) Early Internal and External Dose Magnitude Estimation The Radiation Emergency Assistance Center/Training Site REAC/TS PO Box 117, MS-39 Oak Ridge, TN 37831 (865)576-3131 http://orise.orau.gov/reacts prepared by: Stephen L. (Steve) Sugarman, MS, CHP, CHCM Health Physics Project Manager Cytogenetic Biodosimetry Laboratory Coordinator Early Internal and External Dose Estimation (initial version: 08/2008,

  18. ORISE: Radiation Dose Estimates and Other Compendia

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

    Nuclear Medicine" (M. Stabin, in Pediatric Nuclear Medicine, S. Treves, ed., Springer-Verlag, 1995). The compendium of dose estimates for pregnant women was published...

  19. Compensated count-rate circuit for radiation survey meter

    DOE Patents [OSTI]

    Todd, Richard A. (Powell, TN)

    1981-01-01

    A count-rate compensating circuit is provided which may be used in a portable Geiger-Mueller (G-M) survey meter to ideally compensate for counting loss errors in the G-M tube detector. In a G-M survey meter, wherein the pulse rate from the G-M tube is converted into a pulse rate current applied to a current meter calibrated to indicate dose rate, the compensated circuit generates and controls a reference voltage in response to the rate of pulses from the detector. This reference voltage is gated to the current-generating circuit at a rate identical to the rate of pulses coming from the detector so that the current flowing through the meter is varied in accordance with both the frequency and amplitude of the reference voltage pulses applied thereto so that the count rate is compensated ideally to indicate a true count rate within 1% up to a 50% duty cycle for the detector. A positive feedback circuit is used to control the reference voltage so that the meter output tracks true count rate indicative of the radiation dose rate.

  20. Compensated count-rate circuit for radiation survey meter

    DOE Patents [OSTI]

    Todd, R.A.

    1980-05-12

    A count-rate compensating circuit is provided which may be used in a portable Geiger-Mueller (G-M) survey meter to ideally compensate for couting loss errors in the G-M tube detector. In a G-M survey meter, wherein the pulse rate from the G-M tube is converted into a pulse rate current applied to a current meter calibrated to indicate dose rate, the compensation circuit generates and controls a reference voltage in response to the rate of pulses from the detector. This reference voltage is gated to the current-generating circuit at a rate identical to the rate of pulses coming from the detector so that the current flowing through the meter is varied in accordance with both the frequency and amplitude of the reference voltage pulses applied thereto so that the count rate is compensated ideally to indicate a true count rate within 1% up to a 50% duty cycle for the detector. A positive feedback circuit is used to control the reference voltage so that the meter output tracks true count rate indicative of the radiation dose rate.

  1. SU-E-T-335: Transit Dosimetry for Verification of Dose Delivery Using Electronic Portal Imaging Device (EPID)

    SciTech Connect (OSTI)

    Baek, T; Chung, E; Lee, S; Yoon, M

    2014-06-01

    Purpose: To evaluate the effectiveness of transit dose, measured with an electronic portal imaging device (EPID), in verifying actual dose delivery to patients. Methods: Plans of 5 patients with lung cancer, who received IMRT treatment, were examined using homogeneous solid water phantom and inhomogeneous anthropomorphic phantom. To simulate error in patient positioning, the anthropomorphic phantom was displaced from 5 mm to 10 mm in the inferior to superior (IS), superior to inferior (SI), left to right (LR), and right to left (RL) directions. The transit dose distribution was measured with EPID and was compared to the planed dose using gamma index. Results: Although the average passing rate based on gamma index (GI) with a 3% dose and a 3 mm distance-to-dose agreement tolerance limit was 94.34 % for the transit dose with homogeneous phantom, it was reduced to 84.63 % for the transit dose with inhomogeneous anthropomorphic phantom. The Result also shows that the setup error of 5mm (10mm) in IS, SI, LR and SI direction can Result in the decrease in values of GI passing rates by 1.3% (3.0%), 2.2% (4.3%), 5.9% (10.9%), and 8.9% (16.3%), respectively. Conclusion: Our feasibility study suggests that the transit dose-based quality assurance may provide information regarding accuracy of dose delivery as well as patient positioning.

  2. An updated dose assessment for Rongelap Island

    SciTech Connect (OSTI)

    Robison, W.L.; Conrado, C.L.; Bogen, K.T.

    1994-07-01

    We have updated the radiological dose assessment for Rongelap Island at Rongelap Atoll using data generated from field trips to the atoll during 1986 through 1993. The data base used for this dose assessment is ten fold greater than that available for the 1982 assessment. Details of each data base are presented along with details about the methods used to calculate the dose from each exposure pathway. The doses are calculated for a resettlement date of January 1, 1995. The maximum annual effective dose is 0.26 mSv y{sup {minus}1} (26 mrem y{sup {minus}1}). The estimated 30-, 50-, and 70-y integral effective doses are 0.0059 Sv (0.59 rem), 0.0082 Sv (0.82 rem), and 0.0097 Sv (0.97 rem), respectively. More than 95% of these estimated doses are due to 137-Cesium ({sup 137}Cs). About 1.5% of the estimated dose is contributed by 90-Strontium ({sup 90}Sr), and about the same amount each by 239+240-Plutonium ({sup 239+240}PU), and 241-Americium ({sup 241}Am).

  3. 2007-2009 Power Rate Adjustments (pbl/rates)

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

    Function Review (PFR) Firstgov FY 2007 2009 Power Rate Adjustments BPA's 2007-2009 Wholesale Power Rate Schedules and General Rate Schedule Provisions (GRSPs) took effect on...

  4. WP-07 Power Rate Case (rates/ratecases)

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

    Meetings & Workshops Rate Case Parties Web Site WP-07 Supplemental Rate Case ASC Methodology Adjustments (2007-2009) Adjustments (2002-2006) Previous Rate Cases Financial...

  5. Mixed species radioiodine air sampling readout and dose assessment system

    DOE Patents [OSTI]

    Distenfeld, Carl H. (Mattituck, NY); Klemish, Jr., Joseph R. (Bohemia, NY)

    1978-01-01

    This invention provides a simple, reliable, inexpensive and portable means and method for determining the thyroid dose rate of mixed airborne species of solid and gaseous radioiodine without requiring highly skilled personnel, such as health physicists or electronics technicians. To this end, this invention provides a means and method for sampling a gas from a source of a mixed species of solid and gaseous radioiodine for collection of the mixed species and readout and assessment of the emissions therefrom by cylindrically, concentrically and annularly molding the respective species around a cylindrical passage for receiving a conventional probe-type Geiger-Mueller radiation detector.

  6. Radiological Dose Calculations for Fusion Facilities

    SciTech Connect (OSTI)

    Michael L. Abbott; Lee C. Cadwallader; David A. Petti

    2003-04-01

    This report summarizes the results and rationale for radiological dose calculations for the maximally exposed individual during fusion accident conditions. Early doses per unit activity (Sieverts per TeraBecquerel) are given for 535 magnetic fusion isotopes of interest for several release scenarios. These data can be used for accident assessment calculations to determine if the accident consequences exceed Nuclear Regulatory Commission and Department of Energy evaluation guides. A generalized yearly dose estimate for routine releases, based on 1 Terabecquerel unit releases per radionuclide, has also been performed using averaged site parameters and assumed populations. These routine release data are useful for assessing designs against US Environmental Protection Agency yearly release limits.

  7. [FIXED RATE GUARANTEED OBLIGATIONS]

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

    FIXED RATE GUARANTEED OBLIGATIONS] Draft Date: May 09, 2011 AMR-306688-v5 81-40475664 DATED AS OF [______], 20[__] AMONG THE HOLDERS IDENTIFIED HEREIN, THEIR SUCCESSORS AND PERMITTED ASSIGNS, AND THE UNITED STATES DEPARTMENT OF ENERGY, AS GUARANTOR, AND [_____________________________], AS ADMINISTRATIVE AGENT LOAN GUARANTEE AGREEMENT _____________________________ DOE FIPP Guarantee No. [______] ______________________________ AMR-306688-v5 - i - 81-40475664 CONTENTS Clause Page Section 1.

  8. SU-E-T-238: Monte Carlo Estimation of Cerenkov Dose for Photo-Dynamic Radiotherapy

    SciTech Connect (OSTI)

    Chibani, O; Price, R; Ma, C; Eldib, A; Mora, G

    2014-06-01

    Purpose: Estimation of Cerenkov dose from high-energy megavoltage photon and electron beams in tissue and its impact on the radiosensitization using Protoporphyrine IX (PpIX) for tumor targeting enhancement in radiotherapy. Methods: The GEPTS Monte Carlo code is used to generate dose distributions from 18MV Varian photon beam and generic high-energy (45-MV) photon and (45-MeV) electron beams in a voxel-based tissueequivalent phantom. In addition to calculating the ionization dose, the code scores Cerenkov energy released in the wavelength range 375425 nm corresponding to the pick of the PpIX absorption spectrum (Fig. 1) using the Frank-Tamm formula. Results: The simulations shows that the produced Cerenkov dose suitable for activating PpIX is 4000 to 5500 times lower than the overall radiation dose for all considered beams (18MV, 45 MV and 45 MeV). These results were contradictory to the recent experimental studies by Axelsson et al. (Med. Phys. 38 (2011) p 4127), where Cerenkov dose was reported to be only two orders of magnitude lower than the radiation dose. Note that our simulation results can be corroborated by a simple model where the Frank and Tamm formula is applied for electrons with 2 MeV/cm stopping power generating Cerenkov photons in the 375425 nm range and assuming these photons have less than 1mm penetration in tissue. Conclusion: The Cerenkov dose generated by high-energy photon and electron beams may produce minimal clinical effect in comparison with the photon fluence (or dose) commonly used for photo-dynamic therapy. At the present time, it is unclear whether Cerenkov radiation is a significant contributor to the recently observed tumor regression for patients receiving radiotherapy and PpIX versus patients receiving radiotherapy only. The ongoing study will include animal experimentation and investigation of dose rate effects on PpIX response.

  9. Hanford Environmental Dose Reconstruction Project. Monthly report

    SciTech Connect (OSTI)

    McMakin, A.H.; Cannon, S.D.; Finch, S.M.

    1992-07-01

    The objective of the Hanford Environmental Dose Reconstruction (HEDR) Project is to estimate the radiation doses that individuals and populations could have received from nuclear operations at Hanford since 1944. The TSP consists of experts in environmental pathways, epidemiology, surface-water transport, ground-water transport, statistics, demography, agriculture, meteorology, nuclear engineering, radiation dosimetry, and cultural anthropology. Included are appointed technical members representing the states of Oregon, Washington, and Idaho, a representative of Native American tribes, and an individual representing the public. The project is divided into the following technical tasks. These tasks correspond to the path radionuclides followed from release to impact on humans (dose estimates): Source terms, environmental transport, environmental monitoring data, demography, food consumption, and agriculture, and environmental pathways and dose estimates. Progress is discussed.

  10. Rotational rate sensor

    DOE Patents [OSTI]

    Hunter, Steven L. (Livermore, CA)

    2002-01-01

    A rate sensor for angular/rotational acceleration includes a housing defining a fluid cavity essentially completely filled with an electrolyte fluid. Within the housing, such as a toroid, ions in the fluid are swept during movement from an excitation electrode toward one of two output electrodes to provide a signal for directional rotation. One or more ground electrodes within the housing serve to neutralize ions, thus preventing any effect at the other output electrode.

  11. Residential Solar Valuation Rates

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

    Residential Solar Valuation Rates Karl R. Rábago Rábago Energy LLC 1 The Ideal Residential Solar Tariff ‣ Fair to the utility and non-solar customers ‣ Fair compensation to the solar customer ‣ Decouple compensation from incentives ‣ Align public policy goals (decouple compensation from consumption) ‣ Intuitively sound and administratively simple 2 Historical Antecedents ‣ Externalities ‣ Price ≠ Cost ‣ Green Power ‣ Small Is Profitable (http://www.smallisprofitable.org/)

  12. [FLOATING RATE GUARANTEED OBLIGATIONS]

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

    FLOATING RATE GUARANTEED OBLIGATIONS] Draft Date: May 09, 2011 AMR-306979-v3A 81-40475664 DATED AS OF [______], 20[__] AMONG THE HOLDERS IDENTIFIED HEREIN, THEIR SUCCESSORS AND PERMITTED ASSIGNS, AND THE UNITED STATES DEPARTMENT OF ENERGY, AS GUARANTOR, AND [_____________________________] AS ADMINISTRATIVE AGENT LOAN GUARANTEE AGREEMENT _____________________________ DOE FIPP Guarantee No. [______] ______________________________ AMR-306979-v3A - i - 81-40475664 CONTENTS Clause Page Section 1.

  13. Writing Effective Initial Summary Ratings Initial Summary Rating (ISR)

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

    Initial Summary Ratings Initial Summary Rating (ISR) At the end of the performance cycle, the rating official must prepare an ISR in ePerformance for each SES member who has completed at least 90 days on an established performance plan. Rating officials must take into account the SES member's accomplishments achieved during the performance cycle and the impact to the organization's performance. Rating officials must appraise executives realistically and fairly and avoid ratings inflation.

  14. Rail Coal Transportation Rates

    Gasoline and Diesel Fuel Update (EIA)

    reports Coal Transportation Rates to the Electric Power Sector With Data through 2014 | Release Date: February 23, 2016 | Next Release Date: January 2017 | Previous Data Years Year: 2013 2011 2010 2008 2002 Go Background and Methodology The data in the tables are based on primary data collected by EIA from plant owners and operators on the Form EIA-923, "Power Plant Operations Report" (EIA-923 Data) and supplement data and analysis of coal transportation costs released by EIA in June

  15. October 1996 - September 2001 Wholesale Power Rates (rates/previous...

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

    affecting a specific power purchase. For more specific information see: 1996 Final Wholesale Power and Transmission Rate Schedules: Power Rates (PDF, 84 pages, 188 kb) Ancillary...

  16. SU-E-T-113: Dose Distribution Using Respiratory Signals and Machine Parameters During Treatment

    SciTech Connect (OSTI)

    Imae, T; Haga, A; Saotome, N; Kida, S; Nakano, M; Takeuchi, Y; Shiraki, T; Yano, K; Yamashita, H; Nakagawa, K; Ohtomo, K

    2014-06-01

    Purpose: Volumetric modulated arc therapy (VMAT) is a rotational intensity-modulated radiotherapy (IMRT) technique capable of acquiring projection images during treatment. Treatment plans for lung tumors using stereotactic body radiotherapy (SBRT) are calculated with planning computed tomography (CT) images only exhale phase. Purpose of this study is to evaluate dose distribution by reconstructing from only the data such as respiratory signals and machine parameters acquired during treatment. Methods: Phantom and three patients with lung tumor underwent CT scans for treatment planning. They were treated by VMAT while acquiring projection images to derive their respiratory signals and machine parameters including positions of multi leaf collimators, dose rates and integrated monitor units. The respiratory signals were divided into 4 and 10 phases and machine parameters were correlated with the divided respiratory signals based on the gantry angle. Dose distributions of each respiratory phase were calculated from plans which were reconstructed from the respiratory signals and the machine parameters during treatment. The doses at isocenter, maximum point and the centroid of target were evaluated. Results and Discussion: Dose distributions during treatment were calculated using the machine parameters and the respiratory signals detected from projection images. Maximum dose difference between plan and in treatment distribution was −1.8±0.4% at centroid of target and dose differences of evaluated points between 4 and 10 phases were no significant. Conclusion: The present method successfully evaluated dose distribution using respiratory signals and machine parameters during treatment. This method is feasible to verify the actual dose for moving target.

  17. On effective dose for radiotherapy based on doses to nontarget organs and tissues

    SciTech Connect (OSTI)

    Uselmann, Adam J. Thomadsen, Bruce R.

    2015-02-15

    Purpose: The National Council for Radiation Protection and Measurement (NCRP) published estimates for the collective population dose and the mean effective dose to the population of the United States from medical imaging procedures for 1980/1982 and for 2006. The earlier report ignored the effective dose from radiotherapy and the latter gave a cursory discussion of the topic but again did not include it in the population exposure for various reasons. This paper explains the methodology used to calculate the effective dose in due to radiotherapy procedures in the latter NCRP report and revises the values based on more detailed modeling. Methods: This study calculated the dose to nontarget organs from radiotherapy for reference populations using CT images and published peripheral dose data. Results: Using International Commission on Radiological Protection (ICRP) 60 weighting factors, the total effective dose to nontarget organs in radiotherapy patients is estimated as 298 194 mSv per patient, while the U.S. population effective dose is 0.939 0.610 mSv per person, with a collective dose of 283?000 184?000 person Sv per year. Using ICRP 103 weighting factors, the effective dose is 281 183 mSv per patient, 0.887 0.577 mSv per person in the U.S., and 268?000 174?000 person Sv per year. The uncertainty in the calculations is largely governed by variations in patient size, which was accounted for by considering a range of patient sizes and taking the average treatment site to nontarget organ distance. Conclusions: The methods used to estimate the effective doses from radiotherapy used in NCRP Report No. 160 have been explained and the values updated.

  18. Rate Schedules | Department of Energy

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

    Rate Schedules Rate Schedules One of the major responsibilities of Southeastern is to design, formulate, and justify rate schedules. Repayment studies prepared by the agency determine revenue requirements and appropriate rate levels and these studies for each of Southeastern's four power marketing systems are updated annually. They demonstrate the adequacy of the rates for each system. Rates are considered to be adequate when revenues are sufficient to repay all costs associated with power

  19. Radiotherapy Dose Fractionation under Parameter Uncertainty

    SciTech Connect (OSTI)

    Davison, Matt; Kim, Daero; Keller, Harald

    2011-11-30

    In radiotherapy, radiation is directed to damage a tumor while avoiding surrounding healthy tissue. Tradeoffs ensue because dose cannot be exactly shaped to the tumor. It is particularly important to ensure that sensitive biological structures near the tumor are not damaged more than a certain amount. Biological tissue is known to have a nonlinear response to incident radiation. The linear quadratic dose response model, which requires the specification of two clinically and experimentally observed response coefficients, is commonly used to model this effect. This model yields an optimization problem giving two different types of optimal dose sequences (fractionation schedules). Which fractionation schedule is preferred depends on the response coefficients. These coefficients are uncertainly known and may differ from patient to patient. Because of this not only the expected outcomes but also the uncertainty around these outcomes are important, and it might not be prudent to select the strategy with the best expected outcome.

  20. Low-Dose Radiation Therapy (2 Gy 2) in the Treatment of Orbital Lymphoma

    SciTech Connect (OSTI)

    Fasola, Carolina E.; Jones, Jennifer C.; Huang, Derek D.; Le, Quynh-Thu; Hoppe, Richard T.; Donaldson, Sarah S.

    2013-08-01

    Purpose: Low-dose radiation has become increasingly used in the management of indolent non-Hodgkin lymphoma (NHL), but has not been studied specifically for cases of ocular adnexal involvement. The objective of this study is to investigate the effectiveness of low-dose radiation in the treatment of NHL of the ocular adnexa. Methods and Materials: We reviewed the records of 20 NHL patients with 27 sites of ocular adnexal involvement treated with low-dose radiation consisting of 2 successive fractions of 2 Gy at our institution between 2005 and 2011. The primary endpoint of this study is freedom from local relapse (FFLR). Results: At a median follow-up time of 26 months (range 7-92), the overall response rate for the 27 treated sites was 96%, with a complete response (CR) rate of 85% (n=23) and a partial response rate of 11% (n=3). Among all treated sites with CR, the 2-year FFLR was 100%, with no in-treatment field relapses. The 2-year freedom from regional relapse rate was 96% with 1 case of relapse within the ipsilateral orbit (outside of the treatment field). This patient underwent additional treatment with low-dose radiation of 4 Gy to the area of relapse achieving a CR and no evidence of disease at an additional 42 months of follow-up. Orbital radiation was well tolerated with only mild acute side effects (dry eye, conjunctivitis, transient periorbital edema) in 30% of treated sites without any reports of long-term toxicity. Conclusions: Low-dose radiation with 2 Gy 2 is effective and well tolerated in the treatment of indolent NHL of the ocular adnexa with high response rates and durable local control with the option of reirradiation in the case of locoregional relapse.

  1. Property:OpenEI/UtilityRate/EnergyRateStructure/Tier5Rate | Open...

    Open Energy Info (EERE)

    Property Edit with form History Facebook icon Twitter icon Property:OpenEIUtilityRateEnergyRateStructureTier5Rate Jump to: navigation, search This is a property of type...

  2. Property:OpenEI/UtilityRate/DemandRateStructure/Tier1Rate | Open...

    Open Energy Info (EERE)

    Property Edit with form History Facebook icon Twitter icon Property:OpenEIUtilityRateDemandRateStructureTier1Rate Jump to: navigation, search This is a property of type...

  3. Property:OpenEI/UtilityRate/DemandRateStructure/Tier3Rate | Open...

    Open Energy Info (EERE)

    Property Edit with form History Facebook icon Twitter icon Property:OpenEIUtilityRateDemandRateStructureTier3Rate Jump to: navigation, search This is a property of type...

  4. Property:OpenEI/UtilityRate/EnergyRateStructure/Tier3Rate | Open...

    Open Energy Info (EERE)

    Property Edit with form History Facebook icon Twitter icon Property:OpenEIUtilityRateEnergyRateStructureTier3Rate Jump to: navigation, search This is a property of type...

  5. Property:OpenEI/UtilityRate/EnergyRateStructure/Tier4Rate | Open...

    Open Energy Info (EERE)

    Property Edit with form History Facebook icon Twitter icon Property:OpenEIUtilityRateEnergyRateStructureTier4Rate Jump to: navigation, search This is a property of type...

  6. Characterization of a new photo-fluorescent film dosimeter for high-radiation dose applications

    SciTech Connect (OSTI)

    Murphy, Mark K. ); Miller, Steven D. ); Kovacs, Andras; Mclaughlin, William L.; Slezsak, Istvan

    2001-12-01

    Characterization studies on one of the first versions of the Sunna fluorescent dosimeter have been published by Kovacs and McLaughlin. This present study describes testing results of a newer version of the dosimeter (Model and 61543;, batch 0399-20). This dosimeter is a 1-cm by 3-cm polymeric film of 0.5 mm thickness that emits a green fluorescence component at intensities almost linear with dose. The manufacturing method (injection molding) allows potential batch sizes on the order of a million while maintaining a signal precision on the order of+/- 1%. Studies include dose response, dose rate dependence, energy dependence, post-irradiation stability, environmental effects, and variation of response within a batch. Data for both food irradiation and sterilization dose levels were obtained. The results indicate that the green signal (0.3-200 kGy) works well for food irradiation dose levels, especially in refrigerated facilities that maintain tight temperature control. The green signal also works well in sterilization facilities because its irradiation temperature coefficient above room temperature is minimal at sterilization doses. If the user requires readout results in less than 22 hours after room temperature irradiation, the user can either calibrate for a specific post-irradiation readout time(s) or simply heat the dosimeters in a small laboratory oven to quickly stabilize the signal.

  7. Low Dose Radiation Cancer Risks: Epidemiological and Toxicological Models

    SciTech Connect (OSTI)

    David G. Hoel, PhD

    2012-04-19

    The basic purpose of this one year research grant was to extend the two stage clonal expansion model (TSCE) of carcinogenesis to exposures other than the usual single acute exposure. The two-stage clonal expansion model of carcinogenesis incorporates the biological process of carcinogenesis, which involves two mutations and the clonal proliferation of the intermediate cells, in a stochastic, mathematical way. The current TSCE model serves a general purpose of acute exposure models but requires numerical computation of both the survival and hazard functions. The primary objective of this research project was to develop the analytical expressions for the survival function and the hazard function of the occurrence of the first cancer cell for acute, continuous and multiple exposure cases within the framework of the piece-wise constant parameter two-stage clonal expansion model of carcinogenesis. For acute exposure and multiple exposures of acute series, it is either only allowed to have the first mutation rate vary with the dose, or to have all the parameters be dose dependent; for multiple exposures of continuous exposures, all the parameters are allowed to vary with the dose. With these analytical functions, it becomes easy to evaluate the risks of cancer and allows one to deal with the various exposure patterns in cancer risk assessment. A second objective was to apply the TSCE model with varing continuous exposures from the cancer studies of inhaled plutonium in beagle dogs. Using step functions to estimate the retention functions of the pulmonary exposure of plutonium the multiple exposure versions of the TSCE model was to be used to estimate the beagle dog lung cancer risks. The mathematical equations of the multiple exposure versions of the TSCE model were developed. A draft manuscript which is attached provides the results of this mathematical work. The application work using the beagle dog data from plutonium exposure has not been completed due to the fact that the research project did not continue beyond its first year.

  8. Measurement of the ambient gamma dose equivalent and kerma from the small 252Cf source at 1 meter and the small 60Co source at 2 meters

    SciTech Connect (OSTI)

    Carl, W. F.

    2015-07-30

    NASA Langley Research Center requested a measurement and determination of the ambient gamma dose equivalent rate and kerma at 100 cm from the 252Cf source and determination of the ambient gamma dose equivalent rate and kerma at 200 cm from the 60Co source for the Radiation Budget Instrument Experiment (Rad-X). An Exradin A6 ion chamber with Shonka air-equivalent plastic walls in combination with a Supermax electrometer were used to measure the exposure rate and free-in-air kerma rate of the two sources at the requested distances. The measured gamma exposure, kerma, and dose equivalent rates are tabulated.

  9. Low Dose Gamma Irradiation Potentiates Secondary Exposure to Gamma Rays or Protons in Thyroid Tissue Analogs

    SciTech Connect (OSTI)

    Green, Lora M

    2006-05-25

    We have utilized our unique bioreactor model to produce three-dimensional thyroid tissue analogs that we believe better represent the effects of radiation in vivo than two-dimensional cultures. Our thyroid model has been characterized at multiple levels, including: cell-cell exchanges (bystander), signal transduction, functional changes and modulation of gene expression. We have significant preliminary data on structural, functional, signal transduction and gene expression responses from acute exposures at high doses (50-1000 rads) of gamma, protons and iron (Green et al., 2001a; 2001b; 2002a; 2002b; 2005). More recently, we used our DOE funding (ending Feb 06) to characterize the pattern of radiation modulated gene expression in rat thyroid tissue analogs using low-dose/low-dose rate radiation, plus/minus acute challenge exposures. Findings from these studies show that the low-dose/low-dose rate priming exposures to radiation invoked changes in gene expression profiles that varied with dose and time. The thyrocytes transitioned to a primed state, so that when the tissue analogs were challenged with an acute exposure to radiation they had a muted response (or an increased resistance) to cytopathological changes relative to un-primed cells. We measured dramatic differences in the primed tissue analogs, showing that our original hypothesis was correct: that low dose gamma irradiation will potentiate the repair/adaptation response to a secondary exposure. Implications from these findings are that risk assessments based on classical in vitro tissue culture assays will overestimate risk, and that low dose rate priming results in a reduced response in gene expression to a secondary challenge exposure, which implies that a priming dose provides enhanced protection to thyroid cells grown as tissue analogs. If we can determine that the effects of radiation on our tissue analogs more closely resemble the effects of radiation in vivo, then we can better estimate the risks and modify assign limits to radiation worker and astronauts. Additionally, confirmation that tissue analogs represent a realistic in vivo response to radiation will allow scientists to perform tissue relevant experiments without the expense of using animals. Confirmation of the in vivo approximation of our model will strengthen our findings from the recent completion of our DOE funding which is the subject of the current proposal.

  10. Nuclear Rocket Facility Decommissioning Project: Controlled Explosive Demolition of Neutron-Activated Shield Wall

    SciTech Connect (OSTI)

    Michael R. Kruzic

    2008-06-01

    Located in Area 25 of the Nevada Test Site (NTS), the Test Cell A (TCA) Facility (Figure 1) was used in the early to mid-1960s for testing of nuclear rocket engines, as part of the Nuclear Rocket Development Program, to further space travel. Nuclear rocket testing resulted in the activation of materials around the reactors and the release of fission products and fuel particles. The TCA facility, known as Corrective Action Unit 115, was decontaminated and decommissioned (D&D) from December 2004 to July 2005 using the Streamlined Approach for Environmental Restoration (SAFER) process, under the Federal Facility Agreement and Consent Order. The SAFER process allows environmental remediation and facility closure activities (i.e., decommissioning) to occur simultaneously, provided technical decisions are made by an experienced decision maker within the site conceptual site model. Facility closure involved a seven-step decommissioning strategy. First, preliminary investigation activities were performed, including review of process knowledge documentation, targeted facility radiological and hazardous material surveys, concrete core drilling and analysis, shield wall radiological characterization, and discrete sampling, which proved to be very useful and cost-effective in subsequent decommissioning planning and execution and worker safety. Second, site setup and mobilization of equipment and personnel were completed. Third, early removal of hazardous materials, including asbestos, lead, cadmium, and oil, was performed ensuring worker safety during more invasive demolition activities. Process piping was to be verified void of contents. Electrical systems were de-energized and other systems were rendered free of residual energy. Fourth, areas of high radiological contamination were decontaminated using multiple methods. Contamination levels varied across the facility. Fixed beta/gamma contamination levels ranged up to 2 million disintegrations per minute (dpm)/100 centimeters squared (cm2) beta/gamma. Removable beta/gamma contamination levels seldom exceeded 1,000 dpm/100 cm2, but, in railroad trenches on the reactor pad containing soil on the concrete pad in front of the shield wall, the beta dose rates ranged up to 120 milli-roentgens per hour from radioactivity entrained in the soil. General area dose rates were less than 100 micro-roentgens per hour. Prior to demolition of the reactor shield wall, removable and fixed contaminated surfaces were decontaminated to the best extent possible, using traditional decontamination methods. Fifth, large sections of the remaining structures were demolished by mechanical and open-air controlled explosive demolition (CED). Mechanical demolition methods included the use of conventional demolition equipment for removal of three main buildings, an exhaust stack, and a mobile shed. The 5-foot (ft), 5-inch (in.) thick, neutron-activated reinforced concrete shield was demolished by CED, which had never been performed at the NTS.

  11. 2007-2009 Power Rates Quarterly Updates (pbl/rates)

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

    (PFR) Firstgov FY 2007 2009 Power Rates Quarterly Updates In BPAs 2007-2009 Wholesale Power Rate Case (WP-07), BPA agreed that it would post reports about BPAs power...

  12. October 2005 - March 2006 Power Rates (rates/previous)

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

    above provides a table of monthly Slice, PF, RL, and IP rates with a 30.56% non-Slice LB + FB + SN CRAC adjustment for each month of the six-month rate period. The table below...

  13. April - September 2002 Power Rates (rates/previous)

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

    above provides a table of monthly Slice, PF, RL, and IP rates with a 40.77% non-Slice LB CRAC adjustment for each month of the six-month rate period. The table below is simply a...

  14. October 2004 - March 2005 Power Rates (rates/previous)

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

    The PDF documents above provide tables of monthly Slice, PF, RL, and IP rates with the LB + FB + SN CRAC adjustments for each month of the rate period. The table below is simply...

  15. April - September 2005 Power Rates (rates/previous)

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

    above provides a table of monthly Slice, PF, RL, and IP rates with a 36.93% non-Slice LB + FB + SN CRAC adjustment for each month of the six-month rate period. The table below...

  16. October 2003 - March 2004 Power Rates (rates/previous)

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

    above provides a table of monthly Slice, PF, RL, and IP rates with a 43.66% non-Slice LB + FB + SN CRAC adjustment for each month of the rate period. The table below is simply a...

  17. October 2002 - March 2003 Power Rates (rates/previous)

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

    above provides a table of monthly Slice, PF, RL, and IP rates with a 43.91% non-Slice LB + FB CRAC adjustment for each month of the six-month rate period. The table below is...

  18. October 2001 - March 2002 Power Rates (rates/previous)

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

    above provides a table of monthly Slice, PF, RL, and IP rates with a 46% non-Slice LB CRAC adjustment for each month of the six-month rate period. The table below is simply a...

  19. April - September 2003 Power Rates (rates/previous)

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

    above provides a table of monthly Slice, PF, RL, and IP rates with a 49.50% non-Slice LB + FB CRAC adjustment for each month of the six-month rate period. The table below is...

  20. April - September 2004 Power Rates (rates/previous)

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

    above provides a table of monthly Slice, PF, RL, and IP rates with a 47.00% non-Slice LB + FB + SN CRAC adjustment for each month of the six-month rate period. The table below...

  1. WP-02 Power Rate Case (rates/ratecases)

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

    WP-02 Power Rate Case (Updated on May 7, 2004) In May of 2000, the BPA Administrator signed a Record of Decision (ROD) on the 2002 Final Power Rate Proposal for the October 2001...

  2. FPS-96R Rate Adjustment (rates/ratecases)

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

    Final Firm Power Products and Services (FPS-96R) Rate Adjustment In August 1999, BPA proposed to correct errors in the Firm Power Products and Services rate schedule (FPS-96), and...

  3. National Utility Rate Database: Preprint

    SciTech Connect (OSTI)

    Ong, S.; McKeel, R.

    2012-08-01

    When modeling solar energy technologies and other distributed energy systems, using high-quality expansive electricity rates is essential. The National Renewable Energy Laboratory (NREL) developed a utility rate platform for entering, storing, updating, and accessing a large collection of utility rates from around the United States. This utility rate platform lives on the Open Energy Information (OpenEI) website, OpenEI.org, allowing the data to be programmatically accessed from a web browser, using an application programming interface (API). The semantic-based utility rate platform currently has record of 1,885 utility rates and covers over 85% of the electricity consumption in the United States.

  4. Nominal Performance Biosphere Dose Conversion Factor Analysis

    SciTech Connect (OSTI)

    Wasiolek, Maryla A.

    2000-12-21

    The purpose of this report was to document the process leading to development of the Biosphere Dose Conversion Factors (BDCFs) for the postclosure nominal performance of the potential repository at Yucca Mountain. BDCF calculations concerned twenty-four radionuclides. This selection included sixteen radionuclides that may be significant nominal performance dose contributors during the compliance period of up to 10,000 years, five additional radionuclides of importance for up to 1 million years postclosure, and three relatively short-lived radionuclides important for the human intrusion scenario. Consideration of radionuclide buildup in soil caused by previous irrigation with contaminated groundwater was taken into account in the BDCF development. The effect of climate evolution, from the current arid conditions to a wetter and cooler climate, on the BDCF values was evaluated. The analysis included consideration of different exposure pathway's contribution to the BDCFs. Calculations of nominal performance BDCFs used the GENII-S computer code in a series of probabilistic realizations to propagate the uncertainties of input parameters into the output. BDCFs for the nominal performance, when combined with the concentrations of radionuclides in groundwater allow calculation of potential radiation doses to the receptor of interest. Calculated estimates of radionuclide concentration in groundwater result from the saturated zone modeling. The integration of the biosphere modeling results (BDCFs) with the outcomes of the other component models is accomplished in the Total System Performance Assessment (TSPA) to calculate doses to the receptor of interest from radionuclides postulated to be released to the environment from the potential repository at Yucca Mountain.

  5. Dose masking feature for BNCT radiotherapy planning

    DOE Patents [OSTI]

    Cook, Jeremy L.; Wessol, Daniel E.; Wheeler, Floyd J.

    2000-01-01

    A system for displaying an accurate model of isodoses to be used in radiotherapy so that appropriate planning can be performed prior to actual treatment on a patient. The nature of the simulation of the radiotherapy planning for BNCT and Fast Neutron Therapy, etc., requires that the doses be computed in the entire volume. The "entire volume" includes the patient and beam geometries as well as the air spaces in between. Isodoses derived from the computed doses will therefore extend into the air regions between the patient and beam geometries and thus depict the unrealistic possibility that radiation deposition occurs in regions containing no physical media. This problem is solved by computing the doses for the entire geometry and then masking the physical and air regions along with the isodose contours superimposed over the patient image at the corresponding plane. The user is thus able to mask out (remove) the contour lines from the unwanted areas of the image by selecting the appropriate contour masking region from the raster image.

  6. Suppression of alkylating agent induced cell transformation and gastric ulceration by low-dose alkylating agent pretreatment

    SciTech Connect (OSTI)

    Onodera, Akira; Department of Pharmaceutical Sciences, Kobegakuin University, 1-1-3 Minatojima, Chuo-ku, Kobe 650-8586 ; Kawai, Yuichi; Kashimura, Asako; Ogita, Fumiya; Tsutsumi, Yasuo; Itoh, Norio

    2013-06-14

    Highlights: Low-dose MNNG pretreatment suppresses high-dose MNNG induced in vitro transformation. Gastric ulcers induced by high-dose MNNG decreased after low-dose MNNG pretreatment. Efficacy of low-dose MNNG related to resistance of mutation and oxidative stress. -- Abstract: Exposure to mild stress by chemicals and radiation causes DNA damage and leads to acquired stress resistance. Although the linear no-threshold (LNT) model of safety assessment assumes risk from any dose, evidence from radiological research demonstrates a conflicting hormetic phenomenon known as the hormesis effect. However, the mechanisms underlying radiation hormesis have not yet been clarified, and little is known about the effects of low doses of chemical carcinogens. We analyzed the efficacy of pretreatment with low doses of the alkylating agent N-methyl-N?-nitro-N-nitrosoguanidine (MNNG) on the subsequent induction of cell transformation and gastric ulceration by high-dose MNNG. We used an in vitro Balb/3T3 A31-1-1 cell transformation test and monitored the formation of gastric ulcers in 5-week-old male ICR mice that were administered MNNG in drinking water. The treatment concentrations of MNNG were determined by the cell survival rate and past reports. For low-dose in vitro and in vivo experiments, MNNG was used at 0.028 ?M, and 2.8 ?g/mL, respectively. The frequency of cell transformation induced by 10 ?m MNNG was decreased by low-dose MNNG pretreatment to levels similar to that of spontaneous transformation. In addition, reactive oxygen species (ROS) and mutation frequencies induced by 10 ?m MNNG were decreased by low-dose MNNG pretreatment. Importantly, low-dose MNNG pretreatment had no effect on cell proliferation. In vivo studies showed that the number of gastric ulcers induced by 1 mg/mL MNNG decreased after low-dose MNNG pretreatment. These data indicate that low-dose pretreatment with carcinogens may play a beneficial role in the prevention of chemical toxicity under specified conditions.

  7. Clinical Application of High-Dose, Image-Guided Intensity-Modulated Radiotherapy in High-Risk Prostate Cancer

    SciTech Connect (OSTI)

    Bayley, Andrew, E-mail: Andrew.Bayley@rmp.uhn.on.c [Radiation Medicine Program, Princess Margaret Hospital, Toronto, ON (Canada) and Department of Radiation Oncology, University of Toronto, Toronto, ON (Canada); Rosewall, Tara; Craig, Tim; Bristow, Rob; Chung, Peter; Gospodarowicz, Mary; Menard, Cynthia; Milosevic, Michael; Warde, Padraig; Catton, Charles [Radiation Medicine Program, Princess Margaret Hospital, Toronto, ON (Canada) and Department of Radiation Oncology, University of Toronto, Toronto, ON (Canada)

    2010-06-01

    Purpose: To report the feasibility and early toxicity of dose-escalated image-guided IMRT to the pelvic lymph nodes (LN), prostate (P), and seminal vesicles (SV). Methods and Materials: A total of 103 high-risk prostate cancer patients received two-phase, dose-escalated, image-guided IMRT with 3 years of androgen deprivation therapy. Clinical target volumes (CTVs) were delineated using computed tomography/magnetic resonance co-registration and included the prostate, portions of the SV, and the LN. Planning target volume margins (PTV) used were as follows: P (10 mm, 7 mm posteriorly), SV (10 mm), and LN (5 mm). Organs at risk (OaR) were the rectal and bladder walls, femoral heads, and large and small bowel. The IMRT was planned with an intended dose of 55.1 Gy in 29 fractions to all CTVs (Phase 1), with P+SV consecutive boost of 24.7 Gy in 13 fractions. Daily online image guidance was performed using bony landmarks and intraprostatic markers. Feasibility criteria included delivery of intended doses in 80% of patients, 95% of CTV displacements incorporated within PTV during Phase 1, and acute toxicity rate comparable to that of lower-dose pelvic techniques. Results: A total of 91 patients (88%) received the total prescription dose. All patients received at least 72 Gy. In Phase 1, 63 patients (61%) received the intended 55.1 Gy, whereas 87% of patients received at least 50 Gy. Dose reductions were caused by small bowel and rectal wall constraints. All CTVs received the planned dose in >95% of treatment fractions. There were no Radiation Therapy Oncology Group acute toxicities greater than Grade 3, although there were five incidences equivalent to Grade 3 within a median follow-up of 23 months. Conclusion: These results suggest that dose escalation to the PLN+P+SV using IMRT is feasible, with acceptable rates of acute toxicity.

  8. Dose dependence of mechanical properties in tantalum and tantalum alloys after low temperature irradiation

    SciTech Connect (OSTI)

    Byun, Thak Sang

    2008-01-01

    The dose dependence of mechanical properties was investigated for tantalum and tantalum alloys after low temperature irradiation. Miniature tensile specimens of three pure tantalum metals, ISIS Ta, Aesar Ta1, Aesar Ta2, and one tantalum alloy, Ta-1W, were irradiated by neutrons in the High Flux Isotope Reactor (HFIR) at ORNL to doses ranging from 0.00004 to 0.14 displacements per atom (dpa) in the temperature range 60 C 100 oC. Also, two tantalum-tungsten alloys, Ta-1W and Ta-10W, were irradiated by protons and spallation neutrons in the LANSCE facility at LANL to doses ranging from 0.7 to 7.5 dpa and from 0.7 to 25.2 dpa, respectively, in the temperature range 50 C 160 oC. Tensile tests were performed at room temperature and at 250oC at nominal strain rates of about 10-3 s-1. All neutron-irradiated materials underwent progressive irradiation hardening and loss of ductility with increasing dose. The ISIS Ta experienced embrittlement at 0.14 dpa, while the other metals retained significant necking ductility. Such a premature embrittlement in ISIS Ta is believed to be because of high initial oxygen concentrations picked up during a pre-irradiation anneal. The Ta-1W and Ta-10W specimens irradiated in spallation condition experienced prompt necking at yield since irradiation doses for those specimens were high ( 0.7 dpa). At the highest dose, 25.2 dpa, the Ta-10W alloy specimen broke with little necking strain. Among the test materials, the Ta-1W alloy displayed the best combination of strength and ductility. The plastic instability stress and true fracture stress were nearly independent of dose. Increasing test temperature decreased strength and delayed the onset of necking at yield.

  9. Mammalian Tissue Response to Low Dose Ionizing Radiation: The Role of Oxidative Metabolism and Intercellular Communication

    SciTech Connect (OSTI)

    Azzam, Edouard I

    2013-01-16

    The objective of the project was to elucidate the mechanisms underlying the biological effects of low dose/low dose rate ionizing radiation in organs/tissues of irradiated mice that differ in their susceptibility to ionizing radiation, and in human cells grown under conditions that mimic the natural in vivo environment. The focus was on the effects of sparsely ionizing cesium-137 gamma rays and the role of oxidative metabolism and intercellular communication in these effects. Four Specific Aims were proposed. The integrated outcome of the experiments performed to investigate these aims has been significant towards developing a scientific basis to more accurately estimate human health risks from exposures to low doses ionizing radiation. By understanding the biochemical and molecular changes induced by low dose radiation, several novel markers associated with mitochondrial functions were identified, which has opened new avenues to investigate metabolic processes that may be affected by such exposure. In particular, a sensitive biomarker that is differentially modulated by low and high dose gamma rays was discovered.

  10. MILDOS - A Computer Program for Calculating Environmental Radiation Doses from Uranium Recovery Operations

    SciTech Connect (OSTI)

    Strange, D. L.; Bander, T. J.

    1981-04-01

    The MILDOS Computer Code estimates impacts from radioactive emissions from uranium milling facilities. These impacts are presented as dose commitments to individuals and the regional population within an 80 km radius of the facility. Only airborne releases of radioactive materials are considered: releases to surface water and to groundwater are not addressed in MILDOS. This code is multi-purposed and can be used to evaluate population doses for NEPA assessments, maximum individual doses for predictive 40 CFR 190 compliance evaluations, or maximum offsite air concentrations for predictive evaluations of 10 CFR 20 compliance. Emissions of radioactive materials from fixed point source locations and from area sources are modeled using a sector-averaged Gaussian plume dispersion model, which utilizes user-provided wind frequency data. Mechanisms such as deposition of particulates, resuspension. radioactive decay and ingrowth of daughter radionuclides are included in the transport model. Annual average air concentrations are computed, from which subsequent impacts to humans through various pathways are computed. Ground surface concentrations are estimated from deposition buildup and ingrowth of radioactive daughters. The surface concentrations are modified by radioactive decay, weathering and other environmental processes. The MILDOS Computer Code allows the user to vary the emission sources as a step function of time by adjustinq the emission rates. which includes shutting them off completely. Thus the results of a computer run can be made to reflect changing processes throughout the facility's operational lifetime. The pathways considered for individual dose commitments and for population impacts are: Inhalation External exposure from ground concentrations External exposure from cloud immersion Ingestioo of vegetables Ingestion of meat Ingestion of milk Dose commitments are calculated using dose conversion factors, which are ultimately based on recommendations of the International Commission on Radiological Protection (ICRP). These factors are fixed internally in the code, and are not part of the input option. Dose commitments which are available from the code are as follows: Individual dose commitments for use in predictive 40 CFR 190 compliance evaluations (Radon and short-lived daughters are excluded) Total individual dose commitments (impacts from all available radionuclides are considered) Annual population dose commitments (regional, extraregional, total and cummulative). This model is primarily designed for uranium mill facilities, and should not be used for operations with different radionuclides or processes.

  11. SN-03 Rate Case Workshops (rates/meetings)

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

    Materials Related Link: SN-03 Power Rate Case May 1 & 13, 2003 - Debt and Liquidity Strategies workshops (on BPA Corporate web site) March 27, 2003 - SN CRAC Prescheduling...

  12. Writing Effective Initial Summary Ratings Initial Summary Rating...

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

    Writing an Effective ISR (max 8000 characters including spaces) Before writing: * Read definitions of rating levels and critical element targets carefully * Review Strategic Plan ...

  13. Ensuring the Availability and Reliability of Urea Dosing For...

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

    Ensuring the Availability and Reliability of Urea Dosing For On-Road and Non-Road Ensuring the Availability and Reliability of Urea Dosing For On-Road and Non-Road 2003 DEER...

  14. RADIATION DOSE ESTIMATES TO ADULTS AND CHILDREN FROM VARIOUS

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

    RADIATION DOSE ESTIMATES TO ADULTS AND CHILDREN FROM VARIOUS RADIOPHARMACEUTICALS Latest Revision Date: 4/30/96 Radiation Internal Dose Information Center Oak Ridge Institute for Science and Education P.O. Box 117 Mail Stop 51 Oak Ridge, TN 37831 The radiopharmaceuticals and nuclear medicine studies considered in this report are listed in the Table of Contents on page 2. The radiation dose estimates given in the dose tables are based on the assumptions and models given in Chapter 17, Radiation

  15. How does LANL estimate the potential dose to the public?

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

    Dose to the public How does LANL estimate the potential dose to the public? LANL calculates doses from two different maximally exposed individuals (MEIs): airborne-pathway and all-pathway. The limit that LANL is allowed to contribute is less than 10 millirem. Comparing Radiation Doses A maximally exposed individual, or MEI, is a hypothetical person located on the border of LANL property. MEI assumes the person eats food grown and drinks water found at the location, and also assumes the

  16. Wholesale Power Rate Schedules | Department of Energy

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

    Rate Schedules Wholesale Power Rate Schedules Wholesale Power Rate Schedules October 1, 2012 ALA-1-N Wholesale Power Rate Schedule Area: PowerSouth Energy Cooperative System:...

  17. ARM - Measurement - Radiative heating rate

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

    govMeasurementsRadiative heating rate ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Measurement : Radiative heating rate The heating rate due to the divergence of long and shortwave radiative flux. Categories Atmospheric State, Radiometric Instruments The above measurement is considered scientifically relevant for the following instruments. Refer to the datastream (netcdf) file headers of each instrument for a

  18. Contractor Rating and Feedback Systems

    Broader source: Energy.gov [DOE]

    Better Buildings Residential Workforce/ Business Partners Peer Exchange Call Series: Contractor Rating and Feedback Systems, Call Slides and Discussion Summary, April 24, 2014.

  19. Sustainable Building Rating Systems Summary

    SciTech Connect (OSTI)

    Fowler, Kimberly M.; Rauch, Emily M.

    2006-07-01

    The purpose of this document is to offer information that could be used to compare and contrast sustainable building rating systems.

  20. The increase in animal mortality risk following exposure to sparsely ionizing radiation is not linear quadratic with dose

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

    Haley, Benjamin M.; Paunesku, Tatjana; Grdina, David J.; Woloschak, Gayle E.; Aravindan, Natarajan

    2015-12-09

    The US government regulates allowable radiation exposures relying, in large part, on the seventh report from the committee to estimate the Biological Effect of Ionizing Radiation (BEIR VII), which estimated that most contemporary exposures- protracted or low-dose, carry 1.5 fold less risk of carcinogenesis and mortality per Gy than acute exposures of atomic bomb survivors. This correction is known as the dose and dose rate effectiveness factor for the life span study of atomic bomb survivors (DDREFLSS). As a result, it was calculated by applying a linear-quadratic dose response model to data from Japanese atomic bomb survivors and a limitedmore » number of animal studies.« less

  1. TU-F-17A-08: The Relative Accuracy of 4D Dose Accumulation for Lung Radiotherapy Using Rigid Dose Projection Versus Dose Recalculation On Every Breathing Phase

    SciTech Connect (OSTI)

    Lamb, J; Lee, C; Tee, S; Lee, P; Iwamoto, K; Low, D; Valdes, G; Robinson, C

    2014-06-15

    Purpose: To investigate the accuracy of 4D dose accumulation using projection of dose calculated on the end-exhalation, mid-ventilation, or average intensity breathing phase CT scan, versus dose accumulation performed using full Monte Carlo dose recalculation on every breathing phase. Methods: Radiotherapy plans were analyzed for 10 patients with stage I-II lung cancer planned using 4D-CT. SBRT plans were optimized using the dose calculated by a commercially-available Monte Carlo algorithm on the end-exhalation 4D-CT phase. 4D dose accumulations using deformable registration were performed with a commercially available tool that projected the planned dose onto every breathing phase without recalculation, as well as with a Monte Carlo recalculation of the dose on all breathing phases. The 3D planned dose (3D-EX), the 3D dose calculated on the average intensity image (3D-AVE), and the 4D accumulations of the dose calculated on the end-exhalation phase CT (4D-PR-EX), the mid-ventilation phase CT (4D-PR-MID), and the average intensity image (4D-PR-AVE), respectively, were compared against the accumulation of the Monte Carlo dose recalculated on every phase. Plan evaluation metrics relating to target volumes and critical structures relevant for lung SBRT were analyzed. Results: Plan evaluation metrics tabulated using 4D-PR-EX, 4D-PR-MID, and 4D-PR-AVE differed from those tabulated using Monte Carlo recalculation on every phase by an average of 0.140.70 Gy, - 0.110.51 Gy, and 0.000.62 Gy, respectively. Deviations of between 8 and 13 Gy were observed between the 4D-MC calculations and both 3D methods for the proximal bronchial trees of 3 patients. Conclusions: 4D dose accumulation using projection without re-calculation may be sufficiently accurate compared to 4D dose accumulated from Monte Carlo recalculation on every phase, depending on institutional protocols. Use of 4D dose accumulation should be considered when evaluating normal tissue complication probabilities as well as in clinical situations where target volumes are directly inferior to mobile critical structures.

  2. Dose reconstruction for real-time patient-specific dose estimation in CT

    SciTech Connect (OSTI)

    De Man, Bruno Yin, Zhye; Wu, Mingye; FitzGerald, Paul; Kalra, Mannudeep

    2015-05-15

    Purpose: Many recent computed tomography (CT) dose reduction approaches belong to one of three categories: statistical reconstruction algorithms, efficient x-ray detectors, and optimized CT acquisition schemes with precise control over the x-ray distribution. The latter category could greatly benefit from fast and accurate methods for dose estimation, which would enable real-time patient-specific protocol optimization. Methods: The authors present a new method for volumetrically reconstructing absorbed dose on a per-voxel basis, directly from the actual CT images. The authors’ specific implementation combines a distance-driven pencil-beam approach to model the first-order x-ray interactions with a set of Gaussian convolution kernels to model the higher-order x-ray interactions. The authors performed a number of 3D simulation experiments comparing the proposed method to a Monte Carlo based ground truth. Results: The authors’ results indicate that the proposed approach offers a good trade-off between accuracy and computational efficiency. The images show a good qualitative correspondence to Monte Carlo estimates. Preliminary quantitative results show errors below 10%, except in bone regions, where the authors see a bigger model mismatch. The computational complexity is similar to that of a low-resolution filtered-backprojection algorithm. Conclusions: The authors present a method for analytic dose reconstruction in CT, similar to the techniques used in radiation therapy planning with megavoltage energies. Future work will include refinements of the proposed method to improve the accuracy as well as a more extensive validation study. The proposed method is not intended to replace methods that track individual x-ray photons, but the authors expect that it may prove useful in applications where real-time patient-specific dose estimation is required.

  3. SciSat AM: Stereo 01: 3D Pre-treatment Dose Verification for Stereotactic Body Radiation Therapy Patients

    SciTech Connect (OSTI)

    Asuni, G; Beek, T van; Van Utyven, E; McCowan, P; McCurdy, B.M.C.

    2014-08-15

    Radical treatment techniques such as stereotactic body radiation therapy (SBRT) are becoming popular and they involve delivery of large doses in fewer fractions. Due to this feature of SBRT, a high-resolution, pre-treatment dose verification method that makes use of a 3D patient representation would be appropriate. Such a technique will provide additional information about dose delivered to the target volume(s) and organs-at-risk (OARs) in the patient volume compared to 2D verification methods. In this work, we investigate an electronic portal imaging device (EPID) based pre-treatment QA method which provides an accurate reconstruction of the 3D-dose distribution in the patient model. Customized patient plans are delivered in air and the portal images are collected using the EPID in cine mode. The images are then analysed to determine an estimate of the incident energy fluence. This is then passed to a collapsed-cone convolution dose algorithm which reconstructs a 3D patient dose estimate on the CT imaging dataset. To date, the method has been applied to 5 SBRT patient plans. Reconstructed doses were compared to those calculated by the TPS. Reconstructed mean doses were mostly within 3% of those in the TPS. DVHs of target volumes and OARs compared well. The Chi pass rates using 3%/3mm in the high dose region are greater than 97% in all cases. These initial results demonstrate clinical feasibility and utility of a robust, efficient, effective and convenient pre-treatment QA method using EPID. Research sponsored in part by Varian Medical Systems.

  4. Analysis of Dose at the Site of Second Tumor Formation After Radiotherapy to the Central Nervous System

    SciTech Connect (OSTI)

    Galloway, Thomas J.; Indelicato, Daniel J.; Amdur, Robert J.; Morris, Christopher G.; Swanson, Erika L.; Marcus, Robert B.

    2012-01-01

    Purpose: Second tumors are an uncommon complication of multimodality treatment of childhood cancer. The present analysis attempted to correlate the dose received as a component of primary treatment and the site of the eventual development of a second tumor. Methods and Materials: We retrospectively identified 16 patients who had received radiotherapy to sites in the craniospinal axis and subsequently developed a second tumor. We compared the historical fields and port films of the primary treatment with the modern imaging of the second tumor locations. We classified the location of the second tumors as follows: in the boost field; marginal to the boost field, but in a whole-brain field; in a whole-brain field; marginal to the whole brain/primary treatment field; and distant to the field. We divided the dose received into 3 broad categories: high dose (>45 Gy), moderate dose (20-36 Gy), and low dose (<20 Gy). Results: The most common location of the second tumor was in the whole brain field (57%) and in the moderate-dose range (81%). Conclusions: Our data contradict previous publications that suggested that most second tumors develop in tissues that receive a low radiation dose. Almost all the second tumors in our series occurred in tissue within a target volume in the cranium that had received a moderate dose (20-36 Gy). These findings suggest that a major decrease in the brain volume that receives a moderate radiation dose is the only way to substantially decrease the second tumor rate after central nervous system radiotherapy.

  5. Th Cell Gene Expression and Function in Response to Low Dose and Acute Radiation

    SciTech Connect (OSTI)

    Daila S. Gridley, PhD

    2012-03-30

    FINAL TECHNICAL REPORT Supported by the Low Dose Radiation Research Program, Office of Science U.S. Department of Energy Grant No. DE-FG02-07ER64345 Project ID: 0012965 Award Register#: ER64345 Project Manager: Noelle F. Metting, Sc.D. Phone: 301-903-8309 Division SC-23.2 noelle.metting@science.doe.gov Submitted March 2012 To: https://www.osti.gov/elink/241.3.jsp Title: Th Cell Gene Expression and Function in Response to Low Dose and Acute Radiation PI: Daila S. Gridley, Ph.D. Human low dose radiation data have been derived primarily from studies of space and airline flight personnel, nuclear plant workers and others exposed occupationally, as well as victims in the vicinity of atomic bomb explosions. The findings remain inconclusive due to population inconsistencies and complex interactions among total dose, dose rate, radiation quality and age at exposure. Thus, safe limits for low dose occupational irradiation are currently based on data obtained with doses far exceeding the levels expected for the general population and health risks have been largely extrapolated using the linear-nonthreshold dose-response model. The overall working hypothesis of the present study is that priming with low dose, low-linear energy transfer (LET) radiation can ameliorate the response to acute high-dose radiation exposure. We also propose that the efficacy of low-dose induced protection will be dependent upon the form and regimen of the high-dose exposure: photons versus protons versus simulated solar particle event protons (sSPE). The emphasis has been on gene expression and function of CD4+ T helper (Th) lymphocytes harvested from spleens of whole-body irradiated C57BL/6 mice, a strain that provides the genetic background for many genetically engineered strains. Evaluations of the responses of other selected cells, tissues such as skin, and organs such as lung, liver and brain were also initiated (partially funded by other sources). The long-term goal is to provide information that will be useful in estimating human health risks due to radiation that may occur during exposures in the work environment, nuclear/radiological catastrophes, as well as radiotherapy. Several papers have been published, accepted for publication or are in preparation. A number of poster and oral presentations have been made at scientific conferences and workshops. Archived tissues of various types will continue to be evaluated via funding from other sources (the DoE Low Dose Radiation Research Program, Office of Science and this specific grant will be appropriately included in the Acknowledgements of all subsequent publications/presentations). A post-doc and several students have participated in this study. More detailed description of the accomplishments is described in attached file.

  6. BPA revises oversupply rate proposal

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

    comments until May 22, 2013. The rate-setting process will end with the administrator making a decision based on the record developed in the case. BPA expects to issue a final...

  7. Tier 2 Vintage Rate Workshop

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

    at a Tier 2 rate 3) Combination of the two On Nov 1, 2009, customers made their elections for how they will serve their Above-RHWM Load during the FY 2012-2014 purchase...

  8. Dose discrepancies in the buildup region and their impact on dose calculations for IMRT fields

    SciTech Connect (OSTI)

    Hsu, Shu-Hui; Moran, Jean M.; Chen Yu; Kulasekere, Ravi; Roberson, Peter L.

    2010-05-15

    Purpose: Dose accuracy in the buildup region for radiotherapy treatment planning suffers from challenges in both measurement and calculation. This study investigates the dosimetry in the buildup region at normal and oblique incidences for open and IMRT fields and assesses the quality of the treatment planning calculations. Methods: This study was divided into three parts. First, percent depth doses and profiles (for 5x5, 10x10, 20x20, and 30x30 cm{sup 2} field sizes at 0 deg., 45 deg., and 70 deg. incidences) were measured in the buildup region in Solid Water using an Attix parallel plate chamber and Kodak XV film, respectively. Second, the parameters in the empirical contamination (EC) term of the convolution/superposition (CVSP) calculation algorithm were fitted based on open field measurements. Finally, seven segmental head-and-neck IMRT fields were measured on a flat phantom geometry and compared to calculations using {gamma} and dose-gradient compensation (C) indices to evaluate the impact of residual discrepancies and to assess the adequacy of the contamination term for IMRT fields. Results: Local deviations between measurements and calculations for open fields were within 1% and 4% in the buildup region for normal and oblique incidences, respectively. The C index with 5%/1 mm criteria for IMRT fields ranged from 89% to 99% and from 96% to 98% at 2 mm and 10 cm depths, respectively. The quality of agreement in the buildup region for open and IMRT fields is comparable to that in nonbuildup regions. Conclusions: The added EC term in CVSP was determined to be adequate for both open and IMRT fields. Due to the dependence of calculation accuracy on (1) EC modeling, (2) internal convolution and density grid sizes, (3) implementation details in the algorithm, and (4) the accuracy of measurements used for treatment planning system commissioning, the authors recommend an evaluation of the accuracy of near-surface dose calculations as a part of treatment planning commissioning.

  9. TSD-DOSE: A radiological dose assessment model for treatment, storage, and disposal facilities

    SciTech Connect (OSTI)

    Pfingston, M.; Arnish, J.; LePoire, D.; Chen, S.-Y.

    1998-10-14

    Past practices at US Department of Energy (DOE) field facilities resulted in the presence of trace amounts of radioactive materials in some hazardous chemical wastes shipped from these facilities. In May 1991, the DOE Office of Waste Operations issued a nationwide moratorium on shipping all hazardous waste until procedures could be established to ensure that only nonradioactive hazardous waste would be shipped from DOE facilities to commercial treatment, storage, and disposal (TSD) facilities. To aid in assessing the potential impacts of shipments of mixed radioactive and chemically hazardous wastes, a radiological assessment computer model (or code) was developed on the basis of detailed assessments of potential radiological exposures and doses for eight commercial hazardous waste TSD facilities. The model, called TSD-DOSE, is designed to incorporate waste-specific and site-specific data to estimate potential radiological doses to on-site workers and the off-site public from waste-handling operations at a TSD facility. The code is intended to provide both DOE and commercial TSD facilities with a rapid and cost-effective method for assessing potential human radiation exposures from the processing of chemical wastes contaminated with trace amounts of radionuclides.

  10. Radiation Therapy Photon Beams Dose Conformation According to Dose Distribution Around Intracavitary-Applied Brachytherapy Sources

    SciTech Connect (OSTI)

    Jurkovic, Slaven Zauhar, Gordana; Faj, Dario; Radojcic, Deni Smilovic; Svabic, Manda

    2010-04-01

    Intracavitary application of brachytherapy sources followed by external beam radiation is essential for the local treatment of carcinoma of the cervix. Due to very high doses to the central portion of the target volume delivered by brachytherapy sources, this part of the target volume must be shielded while being irradiated by photon beams. Several shielding techniques are available, from rectangular block and standard cervix wedge to more precise, customized step wedge filters. Because the calculation of a step wedge filter's shape was usually based on effective attenuation coefficient, an approach that accounts, in a more precise way, for the scattered radiation, is suggested. The method was verified under simulated clinical conditions using film dosimetry. Measured data for various compensators were compared to the numerically determined sum of the dose distribution around brachytherapy sources and one of compensated beam. Improvements in total dose distribution are demonstrated, using our method. Agreement between calculation and measurements were within 3%. Sensitivity of the method on sources displacement during treatment has also been investigated.

  11. Dose Response and Post-irradiation Characteristics of the Sunna 535-nm Photo-Fluorescent Film Dosimeter

    SciTech Connect (OSTI)

    Murphy, Mark K.; Kovacs, Andras; Miller, Steven D.; Mclaughlin, William L.

    2003-06-09

    Results of characterization studies on one of the first versions of the Sunna photo-fluorescent dosimeter ? have previously been reported, and describe the performance of the red fluorescence component. This present paper describes dose response and post-irradiation characteristics of the green fluorescence component from the same dosimeter film (Sunna Model ?), which is manufactured using the injection molding technique. This production method may supply batch sizes on the order of 1 million dosimeter film elements while maintaining a signal precision (1?) on the order of ?1% without the need to correct for variability of film thickness. The dosimeter is a 1-cm by 3-cm polymeric film of 0.5-mm thickness that emits green fluorescence at intensities increasing almost linearly with dose. The data presented include dose response, post-irradiation growth, heat treatment, dosimeter aging, dose rate dependence, energy dependence, dose fractionation, variation of response within a batch, and the stability of the fluorimeter response. The results indicate that, as a routine dosimeter, the green signal provides a broad range of response at food irradiation (0.3 to 5 kGy), medical sterilization (5 to 40 kGy), and polymer cross-linking (40 to 250 kGy) dose levels.

  12. BPA Power Rates (pbl/main)

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

    rates, please see the transmission rates web site. Inactive Rate Cases Integrated Business Review (IBR) Integrated Program Review (IPR) Quarterly Business Review (QBR) Content...

  13. Radiological dose assessment for the decontaminated concrete removed from 183-H solar evaporation basins at the Hanford site, Richland, Washington

    SciTech Connect (OSTI)

    Kamboj, S.; Faillace, E.; Yu, C.

    1997-01-01

    Potential maximum radiation dose rates over a 1,000-year time horizon were calculated for exposure to the decontaminated concrete removed from the 183-H Solar Evaporation Basins at the Hanford Site, Richland, Washington. The RESRAD computer code, Version 5.62, which implements the methodology described in the US Department of Energy`s manual for developing residual radioactive material guidelines, was used in this evaluation. Currently, the concrete is not being used. Four potential exposure scenarios were developed for the land area where the decontaminated concrete will be stored. In Scenario A industrial use of the land is assumed; in Scenario B recreational use of the land is assumed; in Scenario C residential use of the land is assumed; and in Scenario D (a plausible but unlikely land-use scenario), the presence of a subsistence farmer in the immediate vicinity of the land is assumed. For Scenarios A and B, water used for drinking is assumed to be surface water from the Columbia River; for Scenarios C and D, groundwater drawn from a well located at the downgradient edge of the storage area is the only source of water for drinking, irrigation, and raising livestock. Conservative parameters values were used to estimate the radiation doses. The results of the evaluation indicate that the US Department of Energy`s dose limit of 100 mrem/yr would not be exceeded for any of the scenarios analyzed. The potential maximum dose rates for Scenarios A, B, C, and D are 0.75, 0.022, 29, 29 mrem/yr, respectively. An uncertainty analysis was performed to determine which parameters have the greatest impact on the estimated doses. The doses in Scenarios C and D were found to be very sensitive to the magnitude of the irrigation rate.

  14. Coal Transportation Rate Sensitivity Analysis

    Reports and Publications (EIA)

    2005-01-01

    On December 21, 2004, the Surface Transportation Board (STB) requested that the Energy Information Administration (EIA) analyze the impact of changes in coal transportation rates on projected levels of electric power sector energy use and emissions. Specifically, the STB requested an analysis of changes in national and regional coal consumption and emissions resulting from adjustments in railroad transportation rates for Wyoming's Powder River Basin (PRB) coal using the National Energy Modeling System (NEMS). However, because NEMS operates at a relatively aggregate regional level and does not represent the costs of transporting coal over specific rail lines, this analysis reports on the impacts of interregional changes in transportation rates from those used in the Annual Energy Outlook 2005 (AEO2005) reference case.

  15. DOE Guidance-Category Rating

    Office of Environmental Management (EM)

    2010 MEMORANDUM FOR HUMAN RESOURCES DIRECTORS FROM: SARA"iJ. Boku1, DIRECToR OF HUMAN C~TAL MANAGEMENT SUBJECT: GUIDANCE MEMORANDUM #10 CATEGORY RATING The purpose of this memorandum is to establish the Department of Energy's (DOE's) policy for the use of Category Rating. Authorities: Public Law 107-296; Title 5 USC 3319; 5 CFR, Part 337, Subpart C., Presidential Memorandum of May 11, 2010 This guidance is established in accordance with 5 USC 3319, which authorizes Federal Agencies to use

  16. RECOVERY OF A TRITIATED LANA SAMPLE FOR DOSE CONVERSION FACTOR DETERMINATION

    SciTech Connect (OSTI)

    Staack, G.

    2010-11-12

    The purpose of this work is to develop a technical basis for both estimating the dose of a worker exposed to respirable tritiated LaNi{sub 4.25}Al{sub 0.75} (LANA) and implementing hazard appropriate controls. Savannah River National Laboratory (SRNL) has agreed to provide Lovelace Respiratory Research Institute (LRRI) with a tritiated LANA sample. LRRI will determine the particle size distribution (PSD) as well as perform dissolution rate studies on the sample in serum ultrafiltrate (SUF), a simulated lung fluid. The rate of tritium release from the sample will be measured over a three month period. Tritium release rate information will be used to calculate a DCF for respirable tritiated LANA.

  17. Passivation layers for reduced total dose effects and ELDRS in linear bipolar devices.

    SciTech Connect (OSTI)

    Dodd, Paul Emerson; Riewe, Leonard Charles; Pease, Ronald L.; Shaneyfelt, Marty Ray; Gupta, Sunny; Maher, Michael C.; Schwank, James Ralph

    2003-07-01

    It is shown that final chip passivation layers can have a significant impact on total dose hardness. A number of final chip passivation layers are evaluated to identify films that mitigate enhanced low-dose-rate sensitivity (ELDRS) in National Semiconductor Corporation's linear bipolar technologies. It is shown that devices fabricated with either a low temperature oxide or a tetraethyl ortho silicate passivation do not exhibit significant ELDRS effects up to 100 krad(SiO{sub 2}). Passivation studies on CMOS SRAMs suggest that it is unlikely that the passivation layers (or processing tools) are acting as a new source of hydrogen, which could drift or diffuse into the oxide and increase ELDRS sensitivity. Instead, it is possible that the passivation layers affect the mechanical stress in the oxide, which may affect oxide trap properties and possibly the release and mobility of hydrogen. Correlations between mechanical stress induced by the passivation layers and radiation degradation are discussed.

  18. Individualized Radical Radiotherapy of Non-Small-Cell Lung Cancer Based on Normal Tissue Dose Constraints: A Feasibility Study

    SciTech Connect (OSTI)

    Baardwijk, Angela van Bosmans, Geert; Boersma, Liesbeth; Wanders, Stofferinus; Dekker, Andre; Dingemans, Anne Marie C.; Bootsma, Gerben; Geraedts, Wiel; Pitz, Cordula; Simons, Jean; Lambin, Philippe; Ruysscher, Dirk de

    2008-08-01

    Purpose: Local recurrence is a major problem after (chemo-)radiation for non-small-cell lung cancer. We hypothesized that for each individual patient, the highest therapeutic ratio could be achieved by increasing total tumor dose (TTD) to the limits of normal tissues, delivered within 5 weeks. We report first results of a prospective feasibility trial. Methods and Materials: Twenty-eight patients with medically inoperable or locally advanced non-small-cell lung cancer, World Health Organization performance score of 0-1, and reasonable lung function (forced expiratory volume in 1 second > 50%) were analyzed. All patients underwent irradiation using an individualized prescribed TTD based on normal tissue dose constraints (mean lung dose, 19 Gy; maximal spinal cord dose, 54 Gy) up to a maximal TTD of 79.2 Gy in 1.8-Gy fractions twice daily. No concurrent chemoradiation was administered. Toxicity was scored using the Common Terminology Criteria for Adverse Events criteria. An {sup 18}F-fluoro-2-deoxy-glucose-positron emission tomography-computed tomography scan was performed to evaluate (metabolic) response 3 months after treatment. Results: Mean delivered dose was 63.0 {+-} 9.8 Gy. The TTD was most often limited by the mean lung dose (32.1%) or spinal cord (28.6%). Acute toxicity generally was mild; only 1 patient experienced Grade 3 cough and 1 patient experienced Grade 3 dysphagia. One patient (3.6%) died of pneumonitis. For late toxicity, 2 patients (7.7%) had Grade 3 cough or dyspnea; none had severe dysphagia. Complete metabolic response was obtained in 44% (11 of 26 patients). With a median follow-up of 13 months, median overall survival was 19.6 months, with a 1-year survival rate of 57.1%. Conclusions: Individualized maximal tolerable dose irradiation based on normal tissue dose constraints is feasible, and initial results are promising.

  19. Dose Recalculation and the Dose-Guided Radiation Therapy (DGRT) Process Using Megavoltage Cone-Beam CT

    SciTech Connect (OSTI)

    Cheung, Joey Aubry, Jean-Francois; Yom, Sue S.; Gottschalk, Alexander R.; Celi, Juan Carlos; Pouliot, Jean

    2009-06-01

    Purpose: At University of California San Francisco, daily or weekly three-dimensional images of patients in treatment position are acquired for image-guided radiation therapy. These images can be used for calculating the actual dose delivered to the patient during treatment. In this article, we present the process of performing dose recalculation on megavoltage cone-beam computed tomography images and discuss possible strategies for dose-guided radiation therapy (DGRT). Materials and Methods: A dedicated workstation has been developed to incorporate the necessary elements of DGRT. Patient image correction (cupping, missing data artifacts), calibration, completion, recontouring, and dose recalculation are all implemented in the workstation. Tools for dose comparison are also included. Examples of image correction and dose analysis using 6 head-and-neck and 2 prostate patient datasets are presented to show possible tracking of interfraction dosimetric endpoint variation over the course of treatment. Results: Analysis of the head-and-neck datasets shows that interfraction treatment doses vary compared with the planning dose for the organs at risk, with the mean parotid dose and spinal cord D{sub 1} increasing by as much as 52% and 10%, respectively. Variation of the coverage to the target volumes was small, with an average D{sub 5} dose difference of 1%. The prostate patient datasets revealed accurate dose coverage to the targeted prostate and varying interfraction dose distributions to the organs at risk. Conclusions: An effective workflow for the clinical implementation of DGRT has been established. With these techniques in place, future clinical developments in adaptive radiation therapy through daily or weekly dosimetric measurements of treatment day images are possible.

  20. Improvements in dose calculation accuracy for small off-axis targets in high dose per fraction tomotherapy

    SciTech Connect (OSTI)

    Hardcastle, Nicholas; Bayliss, Adam; Wong, Jeannie Hsiu Ding; Rosenfeld, Anatoly B.; Tome, Wolfgang A.

    2012-08-15

    Purpose: A recent field safety notice from TomoTherapy detailed the underdosing of small, off-axis targets when receiving high doses per fraction. This is due to angular undersampling in the dose calculation gantry angles. This study evaluates a correction method to reduce the underdosing, to be implemented in the current version (v4.1) of the TomoTherapy treatment planning software. Methods: The correction method, termed 'Super Sampling' involved the tripling of the number of gantry angles from which the dose is calculated during optimization and dose calculation. Radiochromic film was used to measure the dose to small targets at various off-axis distances receiving a minimum of 21 Gy in one fraction. Measurements were also performed for single small targets at the center of the Lucy phantom, using radiochromic film and the dose magnifying glass (DMG). Results: Without super sampling, the peak dose deficit increased from 0% to 18% for a 10 mm target and 0% to 30% for a 5 mm target as off-axis target distances increased from 0 to 16.5 cm. When super sampling was turned on, the dose deficit trend was removed and all peak doses were within 5% of the planned dose. For measurements in the Lucy phantom at 9.7 cm off-axis, the positional and dose magnitude accuracy using super sampling was verified using radiochromic film and the DMG. Conclusions: A correction method implemented in the TomoTherapy treatment planning system which triples the angular sampling of the gantry angles used during optimization and dose calculation removes the underdosing for targets as small as 5 mm diameter, up to 16.5 cm off-axis receiving up to 21 Gy.

  1. Variable gas leak rate valve

    DOE Patents [OSTI]

    Eernisse, Errol P.; Peterson, Gary D.

    1976-01-01

    A variable gas leak rate valve which utilizes a poled piezoelectric element to control opening and closing of the valve. The gas flow may be around a cylindrical rod with a tubular piezoelectric member encircling the rod for seating thereagainst to block passage of gas and for reopening thereof upon application of suitable electrical fields.

  2. Fast repetition rate (FRR) flasher

    DOE Patents [OSTI]

    Kolber, Z.; Falkowski, P.

    1997-02-11

    A fast repetition rate (FRR) flasher is described suitable for high flash photolysis including kinetic chemical and biological analysis. The flasher includes a power supply, a discharge capacitor operably connected to be charged by the power supply, and a flash lamp for producing a series of flashes in response to discharge of the discharge capacitor. A triggering circuit operably connected to the flash lamp initially ionizes the flash lamp. A current switch is operably connected between the flash lamp and the discharge capacitor. The current switch has at least one insulated gate bipolar transistor for switching current that is operable to initiate a controllable discharge of the discharge capacitor through the flash lamp. Control means connected to the current switch for controlling the rate of discharge of the discharge capacitor thereby to effectively keep the flash lamp in an ionized state between successive discharges of the discharge capacitor. Advantageously, the control means is operable to discharge the discharge capacitor at a rate greater than 10,000 Hz and even up to a rate greater than about 250,000 Hz. 14 figs.

  3. Fast repetition rate (FRR) flasher

    DOE Patents [OSTI]

    Kolber, Zbigniew (Shoreham, NY); Falkowski, Paul (Stony Brook, NY)

    1997-02-11

    A fast repetition rate (FRR) flasher suitable for high flash photolysis including kinetic chemical and biological analysis. The flasher includes a power supply, a discharge capacitor operably connected to be charged by the power supply, and a flash lamp for producing a series of flashes in response to discharge of the discharge capacitor. A triggering circuit operably connected to the flash lamp initially ionizes the flash lamp. A current switch is operably connected between the flash lamp and the discharge capacitor. The current switch has at least one insulated gate bipolar transistor for switching current that is operable to initiate a controllable discharge of the discharge capacitor through the flash lamp. Control means connected to the current switch for controlling the rate of discharge of the discharge capacitor thereby to effectively keep the flash lamp in an ionized state between Successive discharges of the discharge capacitor. Advantageously, the control means is operable to discharge the discharge capacitor at a rate greater than 10,000 Hz and even up to a rate greater than about 250,000 Hz.

  4. Evaluation Ratings Definitions (Excluding Utilization of Small...

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

    (Excluding Utilization of Small Business) Rating Definition Note Exceptional ... Definitions (Utilization of Small Business) Rating Definition Note Exceptional ...

  5. Characterization of glycidol-hemoglobin adducts as biomarkers of exposure and in vivo dose

    SciTech Connect (OSTI)

    Honda, Hiroshi; Törnqvist, Margareta; Nishiyama, Naohiro; Kasamatsu, Toshio

    2014-03-15

    Hemoglobin adducts have been used as biomarkers of exposure to reactive chemicals. Glycidol, an animal carcinogen, has been reported to form N-(2,3-dihydroxy-propyl)valine adducts to hemoglobin (diHOPrVal). To support the use of these adducts as markers of glycidol exposure, we investigated the kinetics of diHOPrVal formation and its elimination in vitro and in vivo. Five groups of rats were orally administered a single dose of glycidol ranging from 0 to 75 mg/kg bw, and diHOPrVal levels were measured 24 h after administration. A dose-dependent increase in diHOPrVal levels was observed with high linearity (R{sup 2} = 0.943). Blood sampling at different time points (1, 10, 20, or 40 days) from four groups administered glycidol at 12 mg/kg bw suggested a linear decrease in diHOPrVal levels compatible with the normal turnover of rat erythrocytes (life span, 61 days), with the calculated first-order elimination rate constant (k{sub el}) indicating that the diHOPrVal adduct was chemically stable. Then, we measured the second-order rate constant (k{sub val}) for the reaction of glycidol with N-terminal valine in rat and human hemoglobin in in vitro experiments with whole blood. The k{sub val} was 6.7 ± 1.1 and 5.6 ± 1.3 (pmol/g globin per μMh) in rat and human blood, respectively, indicating no species differences. In vivo doses estimated from k{sub val} and diHOPrVal levels were in agreement with the area under the (concentration–time) curve values determined in our earlier toxicokinetic study in rats. Our results indicate that diHOPrVal is a useful biomarker for quantification of glycidol exposure and for risk assessment. - Highlight: • Glycidol-hemoglobin adduct (diHOPrVal) was characterized for exposure evaluation. • We studied the kinetics of diHOPrVal formation and elimination in vitro and in vivo. • Dose dependent formation and chemical stability were confirmed in the rat study. • In vivo dose (AUC) of glycidol could be estimated from diHOPrVal levels. • diHOPrVal is considered a useful exposure and in vivo dose marker of G.

  6. Dose calculations using MARS for Bremsstrahlung beam stops and collimators in APS beamline stations.

    SciTech Connect (OSTI)

    Dooling, J.; Accelerator Systems Division

    2010-11-01

    The Monte Carlo radiation transport code MARS is used to model the generation of gas bremsstrahlung (GB) radiation from 7-GeV electrons which scatter from residual gas atoms in undulator straight sections within the Advanced Photon Source (APS) storage ring. Additionally, MARS is employed to model the interactions of the GB radiation with components along the x-ray beamlines and then determine the expected radiation dose-rates that result. In this manner, MARS can be used to assess the adequacy of existing shielding or the specifications for new shielding when required. The GB radiation generated in the 'thin-target' of an ID straight section will consist only of photons in a 1/E-distribution up to the full energy of the stored electron beam. Using this analytical model, the predicted GB power for a typical APS 15.38-m insertion device (ID) straight section is 4.59 x 10{sup -7} W/nTorr/mA, assuming a background gas composed of air (Z{sub eff} = 7.31) at room temperature (293K). The total GB power provides a useful benchmark for comparisons between analytical and numerical approaches. We find good agreement between MARS and analytical estimates for total GB power. The extended straight section 'target' creates a radial profile of GB, which is highly peaked centered on the electron beam. The GB distribution reflects the size of the electron beam that creates the radiation. Optimizing the performance of MARS in terms of CPU time per incident trajectory requires the use of a relatively short, high-density gas target (air); in this report, the target density is {rho}L = 2.89 x 10{sup -2} g/cm{sup 2} over a length of 24 cm. MARS results are compared with the contact dose levels reported in TB-20, which used EGS4 for radiation transport simulations. Maximum dose-rates in 1 cc of tissue phantom form the initial basis for comparison. MARS and EGS4 results are approximately the same for maximum 1-cc dose-rates and attenuation in the photon-dominated regions; for thicker targets, however, the dose-rate no longer depends only on photon attenuation, as photoneutrons (PNs) begin to dominate. The GB radiation-induced photoneutron measurements from four different metals (Fe, Cu, W, and Pb) are compared with MARS predictions. The simulated dose-rates for beamline 6-ID are approximately 3-5 times larger than the measured values, whereas those for beamline 11-ID are much closer. Given the uncertainty in local values of pressure and Z, the degree of agreement between MARS and the PN measurements is good. MARS simulations of GB-induced radiation in and around the FOE show the importance of using actual pressure and gas composition (Z{sub eff}) to obtain accurate PN dose. For a beam current of 300 mA, extrapolating pressure data measured in previously published studies predicts an average background gas pressure of 27 nTorr. An average atomic number of Z{sub eff} = 4.0 is obtained from the same studies. In addition, models of copper masks presently in use at the APS are included. Simulations show that inclusion of exit masks make significant differences in both the radiation spatial distribution within the FOE, as well as the peak intensity. Two studies have been conducted with MARS to assess shielding requirements. First, dose levels in contact with the outside wall of the FOE are examined when GB radiation strikes Pb or W beam stops of varying transverse size within the FOE. Four separate phantom regions are utilized to measure the dose, two at beam elevation and two at the horizontal beam position. The first two phantoms are used for scoring FOE dose along the outside and back walls, horizontally; the second two collect dose on the roof and vertically on the back wall. In all cases, the beam stop depth is maintained at 30 cm. Inclusion of front end (FE) exit masks typically cause a 1-2 order-of-magnitude increase in the dose-rates relative to the case with no masks. Masks place secondary bremsstrahlung sources inside the FOE, and therefore they must be shielded appropriately. The MARS model does not fully account for all shielding present

  7. DETERMINATION OF IN-VITRO LUNG SOLUBILITY AND INTAKE-TO-DOSE CONVERSION FACTOR FOR TRITIATED LANTHANUM NICKEL ALUMINUM ALLOY

    SciTech Connect (OSTI)

    Farfan, E.; Labone, T.; Staack, G.; Cheng, Y.; Zhou, Y.; Varallo, T.

    2011-11-11

    A sample of tritiated lanthanum nickel aluminum alloy (LaNi4.25Al0.75 or LANA.75) similar to that used at the Savannah River Site Tritium Facilities was analyzed to estimate the particle size distribution of this metal tritide powder and the rate, at which this material dissolves in the human respiratory tract after it is inhaled. This information is used to calculate the committed effective dose received by a worker after inhaling the material. These doses, which were calculated using the same methodology given in the DOE Tritium Handbook, are presented as inhalation intake-to-dose conversion factors (DCF). The DCF for this metal tritide is less than the DCF for tritiated water and radiation worker bioassay programs designed for tritiated water are adequate to monitor for intakes of this material.

  8. Hydrogen Generation Rate Scoping Study of DOW Corning Antifoam Agent

    SciTech Connect (OSTI)

    Crawford, Charles

    2005-09-27

    The antifoam agent DOW Corning Q2-3183A will be added to waste streams in the Hanford River Protection Program-Waste Treatment and Immobilization Plant (RPP-WTP) to prevent foaming. It consists mostly of polydimethylsiloxane (PDMS) and polypropylene glycol (PPG). These and other minor constituents of the antifoam have organic constituents that may participate in radiolytic and chemical reactions that produce hydrogen in Hanford waste. It has been recommended by The WTP R&T Department recommended personnel to treat the organic compounds of the antifoam like the in a similar manner as other organic compounds that are native to the Hanford waste with respect to hydrogen production. This testing has investigated the radiolytic and thermal production of hydrogen from antifoam added to simulant waste solutions to determine if the organic components of the antifoam produce hydrogen in the same manner as the native organic species in Hanford waste. Antifoam additions for this testing were in the range of 4 to 10 wt% to ensure adequate hydrogen detection. Test conditions were selected to bound exposures to the antifoam agent in the WTP. These levels are higher than previously recommended values of 350 mg/L for actual applications in WTP tanks containing air spargers and pulse jet mixers. Limited degradation analyses for the organic components of the antifoam were investigated in this study. A more detailed study involving analyses of antifoam degradation and product formation is in progress at SRNL and results from that study will be reported at a later time. The total organic carbon (TOC) content of the Q2-3183A antifoam was measured to be 39.7 {+-} 4.9 wt% TOC. This measurement was performed in triplicate with on three different dilutions of the pure antifoam liquid using a TOC combustion analyzer instrument with catalytic oxidation, followed by CO{sub 2} quantification using an infrared detector. Test results from this study indicate that the WTP HGR correlation conservatively bounds hydrogen generation rates (HGRs) from antifoam-containing simulants if the antifoam organic components are treated the same as other native organics. Tests that used the combination of radiolysis and thermolysis conducted on simulants containing antifoam produced measured hydrogen that was bounded by the WTP correlation. These tests used the bounding WTP temperature of 90 C and a dose rate of 1.8 x 10{sup 5} rad/hr. This dose rate is about ten times higher than the dose rate equivalent calculated for a bounding Hanford sludge slurry composition of 10 Ci/L, or 2 x 10{sup 4} rad/hr. Hydrogen was measured using a quadrupole mass spectroscopy instrument. Based on the analyses from the 4wt% and 10wt% antifoam samples, it is expected that the HGR results are directly proportional to the antifoam concentration added. A native organic-containing simulant that did not contain any added antifoam also produced a measurable radiolytic/thermal hydrogen rates that was in bounded by the WTP correlation. A base simulant with no added organic produced a measurable radiolytic/thermal HGR that was {approx}2X higher than the predicted HGR. Analysis of antifoam-containing simulants after prolonged irradiation of 52 Mrad and heating (23 days at 90 C) indicates that essentially all of the PDMS and greater than 60% of the PPG components are degraded, likely to lower molecular weight species. The antifoam components were analyzed by extraction from the salt simulants, followed by gel permeation chromatography (GPC) by personnel at Dow Corning. A more detailed study of the antifoam degradation and product formation from radiolysis and thermolysis is currently in progress at SRNL. That study uses a dose rate of about 2 x 10{sup 4} rad/hr and bounding temperatures of 90 C. Results from that study will be reported in a future report.

  9. Primary explants of human uroepithelium show an unusual response to low-dose irradiation with cobalt-60 gamma rays

    SciTech Connect (OSTI)

    Mothersill, C.; Seymour, C.B.; Harney, J.; Parsons, K.; Lyng, F.; Cottell, D.; Murphy, D.M.

    1995-05-01

    Recent results using very low doses of radiation have suggested that there is a hypersensitive region where cultures show an enhanced level of cell killing leading to a non-monotonic survival curve. This effect has been observed at doses below 2 Gy in mammalian systems and at much higher doses in insect cells. In this paper we report observation of the effect in primary human uroepithelial cell cultures. The effect was measured using a postirradiation proliferation assay where irradiated explants of standard size were allowed to proliferate for 14 days after exposure to {sup 60}Co{gamma} irradiation. By 14 days the majority of cultures derived from explants irradiated with 2-5 Gy showed little evidence of growth inhibition and cell numbers approached or even exceeded those obtained in the controls. There was, however, a significant reduction in cell number and growth rate in all cultures exposed to doses lower than 1 Gy. Oncoprotein and EGFR expression were also measured in these cultures and were significantly increased. Morphological evidence of apoptosis was present in all irradiated cultures at 4 h after exposure, but this persisted for longer periods in cultures exposed to low doses. 18 refs., 2 figs., 4 tabs.

  10. Peak Dose Assessment for Proposed DOE-PPPO Authorized Limits

    SciTech Connect (OSTI)

    Maldonado, Delis

    2012-06-01

    The Oak Ridge Institute for Science and Education (ORISE), a U.S. Department of Energy (DOE) prime contractor, was contracted by the DOE Portsmouth/Paducah Project Office (DOE-PPPO) to conduct a peak dose assessment in support of the Authorized Limits Request for Solid Waste Disposal at Landfill C-746-U at the Paducah Gaseous Diffusion Plant (DOE-PPPO 2011a). The peak doses were calculated based on the DOE-PPPO Proposed Single Radionuclides Soil Guidelines and the DOE-PPPO Proposed Authorized Limits (AL) Volumetric Concentrations available in DOE-PPPO 2011a. This work is provided as an appendix to the Dose Modeling Evaluations and Technical Support Document for the Authorized Limits Request for the C-746-U Landfill at the Paducah Gaseous Diffusion Plant, Paducah, Kentucky (ORISE 2012). The receptors evaluated in ORISE 2012 were selected by the DOE-PPPO for the additional peak dose evaluations. These receptors included a Landfill Worker, Trespasser, Resident Farmer (onsite), Resident Gardener, Recreational User, Outdoor Worker and an Offsite Resident Farmer. The RESRAD (Version 6.5) and RESRAD-OFFSITE (Version 2.5) computer codes were used for the peak dose assessments. Deterministic peak dose assessments were performed for all the receptors and a probabilistic dose assessment was performed only for the Offsite Resident Farmer at the request of the DOE-PPPO. In a deterministic analysis, a single input value results in a single output value. In other words, a deterministic analysis uses single parameter values for every variable in the code. By contrast, a probabilistic approach assigns parameter ranges to certain variables, and the code randomly selects the values for each variable from the parameter range each time it calculates the dose (NRC 2006). The receptor scenarios, computer codes and parameter input files were previously used in ORISE 2012. A few modifications were made to the parameter input files as appropriate for this effort. Some of these changes included increasing the time horizon beyond 1,050 years (yr), and using the radionuclide concentrations provided by the DOE-PPPO as inputs into the codes. The deterministic peak doses were evaluated within time horizons of 70 yr (for the Landfill Worker and Trespasser), 1,050 yr, 10,000 yr and 100,000 yr (for the Resident Farmer [onsite], Resident Gardener, Recreational User, Outdoor Worker and Offsite Resident Farmer) at the request of the DOE-PPPO. The time horizons of 10,000 yr and 100,000 yr were used at the request of the DOE-PPPO for informational purposes only. The probabilistic peak of the mean dose assessment was performed for the Offsite Resident Farmer using Technetium-99 (Tc-99) and a time horizon of 1,050 yr. The results of the deterministic analyses indicate that among all receptors and time horizons evaluated, the highest projected dose, 2,700 mrem/yr, occurred for the Resident Farmer (onsite) at 12,773 yr. The exposure pathways contributing to the peak dose are ingestion of plants, external gamma, and ingestion of milk, meat and soil. However, this receptor is considered an implausible receptor. The only receptors considered plausible are the Landfill Worker, Recreational User, Outdoor Worker and the Offsite Resident Farmer. The maximum projected dose among the plausible receptors is 220 mrem/yr for the Outdoor Worker and it occurs at 19,045 yr. The exposure pathways contributing to the dose for this receptor are external gamma and soil ingestion. The results of the probabilistic peak of the mean dose analysis for the Offsite Resident Farmer indicate that the average (arithmetic mean) of the peak of the mean doses for this receptor is 0.98 mrem/yr and it occurs at 1,050 yr. This dose corresponds to Tc-99 within the time horizon of 1,050 yr.

  11. Emergency Doses (ED) - Revision 3: A calculator code for environmental dose computations

    SciTech Connect (OSTI)

    Rittmann, P.D.

    1990-12-01

    The calculator program ED (Emergency Doses) was developed from several HP-41CV calculator programs documented in the report Seven Health Physics Calculator Programs for the HP-41CV, RHO-HS-ST-5P (Rittman 1984). The program was developed to enable estimates of offsite impacts more rapidly and reliably than was possible with the software available for emergency response at that time. The ED - Revision 3, documented in this report, revises the inhalation dose model to match that of ICRP 30, and adds the simple estimates for air concentration downwind from a chemical release. In addition, the method for calculating the Pasquill dispersion parameters was revised to match the GENII code within the limitations of a hand-held calculator (e.g., plume rise and building wake effects are not included). The summary report generator for printed output, which had been present in the code from the original version, was eliminated in Revision 3 to make room for the dispersion model, the chemical release portion, and the methods of looping back to an input menu until there is no further no change. This program runs on the Hewlett-Packard programmable calculators known as the HP-41CV and the HP-41CX. The documentation for ED - Revision 3 includes a guide for users, sample problems, detailed verification tests and results, model descriptions, code description (with program listing), and independent peer review. This software is intended to be used by individuals with some training in the use of air transport models. There are some user inputs that require intelligent application of the model to the actual conditions of the accident. The results calculated using ED - Revision 3 are only correct to the extent allowed by the mathematical models. 9 refs., 36 tabs.

  12. A two-dimensional matrix correction for off-axis portal dose prediction errors

    SciTech Connect (OSTI)

    Bailey, Daniel W.; Kumaraswamy, Lalith; Bakhtiari, Mohammad; Podgorsak, Matthew B.

    2013-05-15

    Purpose: This study presents a follow-up to a modified calibration procedure for portal dosimetry published by Bailey et al. ['An effective correction algorithm for off-axis portal dosimetry errors,' Med. Phys. 36, 4089-4094 (2009)]. A commercial portal dose prediction system exhibits disagreement of up to 15% (calibrated units) between measured and predicted images as off-axis distance increases. The previous modified calibration procedure accounts for these off-axis effects in most regions of the detecting surface, but is limited by the simplistic assumption of radial symmetry. Methods: We find that a two-dimensional (2D) matrix correction, applied to each calibrated image, accounts for off-axis prediction errors in all regions of the detecting surface, including those still problematic after the radial correction is performed. The correction matrix is calculated by quantitative comparison of predicted and measured images that span the entire detecting surface. The correction matrix was verified for dose-linearity, and its effectiveness was verified on a number of test fields. The 2D correction was employed to retrospectively examine 22 off-axis, asymmetric electronic-compensation breast fields, five intensity-modulated brain fields (moderate-high modulation) manipulated for far off-axis delivery, and 29 intensity-modulated clinical fields of varying complexity in the central portion of the detecting surface. Results: Employing the matrix correction to the off-axis test fields and clinical fields, predicted vs measured portal dose agreement improves by up to 15%, producing up to 10% better agreement than the radial correction in some areas of the detecting surface. Gamma evaluation analyses (3 mm, 3% global, 10% dose threshold) of predicted vs measured portal dose images demonstrate pass rate improvement of up to 75% with the matrix correction, producing pass rates that are up to 30% higher than those resulting from the radial correction technique alone. As in the 1D correction case, the 2D algorithm leaves the portal dosimetry process virtually unchanged in the central portion of the detector, and thus these correction algorithms are not needed for centrally located fields of moderate size (at least, in the case of 6 MV beam energy).Conclusion: The 2D correction improves the portal dosimetry results for those fields for which the 1D correction proves insufficient, especially in the inplane, off-axis regions of the detector. This 2D correction neglects the relatively smaller discrepancies that may be caused by backscatter from nonuniform machine components downstream from the detecting layer.

  13. Introduction to benchmark dose methods and U.S. EPA's benchmark dose software (BMDS) version 2.1.1

    SciTech Connect (OSTI)

    Davis, J. Allen; Gift, Jeffrey S.; Zhao, Q. Jay

    2011-07-15

    Traditionally, the No-Observed-Adverse-Effect-Level (NOAEL) approach has been used to determine the point of departure (POD) from animal toxicology data for use in human health risk assessments. However, this approach is subject to substantial limitations that have been well defined, such as strict dependence on the dose selection, dose spacing, and sample size of the study from which the critical effect has been identified. Also, the NOAEL approach fails to take into consideration the shape of the dose-response curve and other related information. The benchmark dose (BMD) method, originally proposed as an alternative to the NOAEL methodology in the 1980s, addresses many of the limitations of the NOAEL method. It is less dependent on dose selection and spacing, and it takes into account the shape of the dose-response curve. In addition, the estimation of a BMD 95% lower bound confidence limit (BMDL) results in a POD that appropriately accounts for study quality (i.e., sample size). With the recent advent of user-friendly BMD software programs, including the U.S. Environmental Protection Agency's (U.S. EPA) Benchmark Dose Software (BMDS), BMD has become the method of choice for many health organizations world-wide. This paper discusses the BMD methods and corresponding software (i.e., BMDS version 2.1.1) that have been developed by the U.S. EPA, and includes a comparison with recently released European Food Safety Authority (EFSA) BMD guidance.

  14. Wholesale Power Rate Schedules | Department of Energy

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

    Power Rate Schedules October 1, 2011 CBR-1-H Wholesale Power Rate Schedule Area: Big Rivers and Henderson, KY System: CU October 1, 2011 CM-1-H Wholesale Power Rate...

  15. Utility Rate | OpenEI Community

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    Rate Home > Utility Rate > Posts by term > Utility Rate Content Group Activity By term Q & A Feeds Term: electric load data Type Term Title Author Replies Last Post sort icon...

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    Rate Home > Utility Rate > Posts by term > Utility Rate Content Group Activity By term Q & A Feeds Term: Illinois State University Type Term Title Author Replies Last Post sort...

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  12. SU-E-T-205: Improving Quality Assurance of HDR Brachytherapy: Verifying Agreement Between Planned and Delivered Dose Distributions Using DICOM RTDose and Advanced Film Dosimetry

    SciTech Connect (OSTI)

    Palmer, A L; Bradley, D A; Nisbet, A

    2014-06-01

    Purpose: HDR brachytherapy is undergoing significant development, and quality assurance (QA) checks must keep pace. Current recommendations do not adequately verify delivered against planned dose distributions: This is particularly relevant for new treatment planning system (TPS) calculation algorithms (non TG-43 based), and an era of significant patient-specific plan optimisation. Full system checks are desirable in modern QA recommendations, complementary to device-centric individual tests. We present a QA system incorporating TPS calculation, dose distribution export, HDR unit performance, and dose distribution measurement. Such an approach, more common in external beam radiotherapy, has not previously been reported in the literature for brachytherapy. Methods: Our QA method was tested at 24 UK brachytherapy centres. As a novel approach, we used the TPS DICOM RTDose file export to compare planned dose distribution with that measured using Gafchromic EBT3 films placed around clinical brachytherapy treatment applicators. Gamma analysis was used to compare the dose distributions. Dose difference and distance to agreement were determined at prescription Point A. Accurate film dosimetry was achieved using a glass compression plate at scanning to ensure physically-flat films, simultaneous scanning of known dose films with measurement films, and triple-channel dosimetric analysis. Results: The mean gamma pass rate of RTDose compared to film-measured dose distributions was 98.1% at 3%(local), 2 mm criteria. The mean dose difference, measured to planned, at Point A was -0.5% for plastic treatment applicators and -2.4% for metal applicators, due to shielding not accounted for in TPS. The mean distance to agreement was 0.6 mm. Conclusion: It is recommended to develop brachytherapy QA to include full-system verification of agreement between planned and delivered dose distributions. This is a novel approach for HDR brachytherapy QA. A methodology using advanced film dosimetry and gamma comparison to DICOM RTDose files has been demonstrated as suitable to fulfil this need.

  13. How does LANL estimate the potential dose to the public?

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

    year 0.5 - 3 Dental X-rayeach 2 - 3 Mammogram 3 Radon in NMyear 300 Flighthour 0.4 Chest X-ray 6 Barium swallow 150 LANL calculates doses from two different MEIs:...

  14. Low dose ionizing radiation detection using conjugated polymers

    SciTech Connect (OSTI)

    Silva, E.A.B.; Borin, J.F.; Nicolucci, P.; Graeff, C.F.O.; Netto, T. Ghilardi; Bianchi, R.F.

    2005-03-28

    In this work, the effect of gamma radiation on the optical properties of poly[2-methoxy-5-(2{sup '}-ethylhexyloxy)-p-phenylenevinylene] (MEH-PPV) is studied. The samples were irradiated at room temperature with different doses from 0 Gy to 152 Gy using a {sup 60}Co gamma ray source. For thin films, significant changes in the UV-visible spectra were only observed at high doses (>1 kGy). In solution, shifts in absorption peaks are observed at low doses (<10 Gy), linearly dependent on dose. The shifts are explained by conjugation reduction, and possible causes are discussed. Our results indicate that MEH-PPV solution can be used as a dosimeter adequate for medical applications.

  15. LB CRAC Workshops (rates/meetings)

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

    Load-Based (LB) CRAC Power Rate Adjustment Workshop Materials Related Links: Power Rate Adjustments > Load-Based (LB) CRAC December 13, 2006 LB CRAC Workshop Materials (updated...

  16. utility rate | OpenEI Community

    Open Energy Info (EERE)

    utility Utility Companies utility rate Utility Rates version 1 version 2 version 3 web service Smart meter After several months of development and testing, the next...

  17. FOOD CONSUMPTION PATTERNS OF THE OZYORSK POPULATION IN 1948-1966, IMPORTANT FOR ESTIMATING PERORAL COMPONENT OF INTERNAL EXPOSURE DOSES

    SciTech Connect (OSTI)

    Mokrov, Y.; Martyushov, V. Z.; Stukalov, Pavel M.; Ivanov, I. A.; Beregich, D. A.; Anspaugh, L. R.; Napier, Bruce A.

    2008-06-01

    Results of reconstruction of food consumption patterns are presented for the residents of Ozyorsk for the period of 1948-1966. The reconstruction was performed on the basis analysis of the archive data. The given period of time is characterized by maximum releases into the atmosphere from the Mayak PA sources, and, therefore, it is considered to be the most significant period for calculating peroral component contribution to effective exposure doses to the population. The paper describes main foodstuff suppliers (regions) and their economic indices, as well as delivery rates and consumption rates for most important foodstuffs (primarily whole milk).

  18. Kootenai River Nutrient Dosing System and N-P Consumption: Year 2008.

    SciTech Connect (OSTI)

    Holderman, Charles

    2009-02-19

    In early 2006 we designed and built low energy consumption, pump-operated system, for dosing of the liquid nutrient in the summer 2006 season. This operated successfully, and the system was used again during the 2007 and 2008 seasons for dosing. During the early winter period, 2008, laboratory tests were made of the liquid nutrient pump system, and it was noted that small amounts of air were being entrained on the suction side of the pump, during conditions when the inlet pressure was low. It was believed that this was the cause of diurnal fluctuations in the flow supplied, characteristic of the 2007 year flow data. Replacement of '0' rings on the inlet side of the pumps was the solution to this problem, and when tested in the field during the summer season, the flow supplied was found to be stable. A decision was made by the IKERT committee at the meeting of 20th to 21st May 2008 (held in Coeur d'Alene, Idaho) to use an injection flow rate of liquid fertilizer (polyammonium phosphate 10-34-0) to achieve a target phosphorus concentration of 3.0 {micro}g/L, after complete mixing in the river. This target concentration was the same as that used in 2006 and 2007. The proposed starting date was as early as possible in June 2008. Plans were made to measure the dosing flow in three ways. Two of the three methods of flow measurement (1 and 2 below) are inter-dependent. These were: (1) Direct measurement of flow rate by diverting dosing flow into a 1000 mL volume standard flask. The flow rate was computed by dividing the flask volume by the time required to fill the flask. This was done a few times only during the summer period. (2) Adjusting the flow rate reading of the Gamma dosing pump using the 'calibration' function to achieve agreement with the flow rate computed by method 1 above. (3) Direct measurement by electrical signal from conductive fluid passing through a magnetic field (Seametrics meter, as used in previous years). Values were recorded every 4 minutes by a data-logger. This instrument has been shown to be reliable, and in agreement with method 1 to within the expected uncertainty (within 2%). Liquid nutrients were delivered to the site in late May, and system testing was done the same day. High concentrations of suspended sediment in the water column, as indicated by shallow Secchi depth readings, were present in the river in the last part of May, into June. A plan was made to delay the start up of nutrient addition to a date later than 1st June, because the aquatic productivity was almost certainly to be compromised by insufficient light availability. Daily monitoring of Secchi depths was done, showing declining turbidity in early June. A decision was made to start the system on 15th June, by which time conditions were good.

  19. Dose optimization in cardiac x-ray imaging

    SciTech Connect (OSTI)

    Gislason-Lee, Amber J.; McMillan, Catherine; Cowen, Arnold R.; Davies, Andrew G.

    2013-09-15

    Purpose: The aim of this research was to optimize x-ray image quality to dose ratios in the cardiac catheterization laboratory. This study examined independently the effects of peak x-ray tube voltage (kVp), copper (Cu), and gadolinium (Gd) x-ray beam filtration on the image quality to radiation dose balance for adult patient sizes.Methods: Image sequences of polymethyl methacrylate (PMMA) phantoms representing two adult patient sizes were captured using a modern flat panel detector based x-ray imaging system. Tin and copper test details were used to simulate iodine-based contrast medium and stents/guide wires respectively, which are used in clinical procedures. Noise measurement for a flat field image and test detail contrast were used to calculate the contrast to noise ratio (CNR). Entrance surface dose (ESD) and effective dose measurements were obtained to calculate the figure of merit (FOM), CNR{sup 2}/dose. This FOM determined the dose efficiency of x-ray spectra investigated. Images were captured with 0.0, 0.1, 0.25, 0.4, and 0.9 mm Cu filtration and with a range of gadolinium oxysulphide (Gd{sub 2}O{sub 2}S) filtration.Results: Optimum x-ray spectra were the same for the tin and copper test details. Lower peak tube voltages were generally favored. For the 20 cm phantom, using 2 Lanex Fast Back Gd{sub 2}O{sub 2}S screens as x-ray filtration at 65 kVp provided the highest FOM considering ESD and effective dose. Considering ESD, this FOM was only marginally larger than that from using 0.4 mm Cu at 65 kVp. For the 30 cm phantom, using 0.25 mm copper filtration at 80 kVp was most optimal; considering effective dose the FOM was highest with no filtration at 65 kVp.Conclusions: These settings, adjusted for x-ray tube loading limits and clinically acceptable image quality, should provide a useful option for optimizing patient dose to image quality in cardiac x-ray imaging. The same optimal x-ray beam spectra were found for both the tin and copper details, suggesting that iodine contrast based imaging and visualization of interventional devices could potentially be optimized for dose using similar x-ray beam spectra.

  20. Combined Retrieval, Microphysical Retrievals and Heating Rates

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

    Feng, Zhe

    2013-02-22

    Microphysical retrievals and heating rates from the AMIE/Gan deployment using the PNNL Combined Retrieval.

  1. Combined Retrieval, Microphysical Retrievals and Heating Rates

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

    Feng, Zhe

    Microphysical retrievals and heating rates from the AMIE/Gan deployment using the PNNL Combined Retrieval.

  2. Wholesale Power Rate Schedules | Department of Energy

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

    Rate Schedules » Wholesale Power Rate Schedules Wholesale Power Rate Schedules October 1, 2012 ALA-1-N Wholesale Power Rate Schedule Area: PowerSouth Energy Cooperative System: Georgia-Alabama-South Carolina October 1, 2012 Duke-1-E Wholesale Power Rate Schedule Area: Duke On-System System: Georgia-Alabama-South Carolina October 1, 2012 Duke-2-E Wholesale Power Rate Schedule Area: Central System: Georgia-Alabama-South Carolina October 1, 2012 Duke-3-E Wholesale Power Rate Schedule Area: None

  3. Low-Dose Radiation Cataract and Genetic Determinants of Radiosensitivity

    SciTech Connect (OSTI)

    Kleiman, Norman Jay

    2013-11-30

    The lens of the eye is one of the most radiosensitive tissues in the body. Ocular ionizing radiation exposure results in characteristic, dose related, progressive lens changes leading to cataract formation. While initial, early stages of lens opacification may not cause visual disability, the severity of such changes progressively increases with dose until vision is impaired and cataract extraction surgery may be required. Because of the transparency of the eye, radiation induced lens changes can easily be followed non-invasively over time. Thus, the lens provides a unique model system in which to study the effects of low dose ionizing radiation exposure in a complex, highly organized tissue. Despite this observation, considerable uncertainties remain surrounding the relationship between dose and risk of developing radiation cataract. For example, a growing number of human epidemiological findings suggest significant risk among various groups of occupationally and accidentally exposed individuals and confidence intervals that include zero dose. Nevertheless, questions remain concerning the relationship between lens opacities, visual disability, clinical cataract, threshold dose and/or the role of genetics in determining radiosensitivity. Experimentally, the response of the rodent eye to radiation is quite similar to that in humans and thus animal studies are well suited to examine the relationship between radiation exposure, genetic determinants of radiosensitivity and cataractogenesis. The current work has expanded our knowledge of the low-dose effects of X-irradiation or high-LET heavy ion exposure on timing and progression of radiation cataract and has provided new information on the genetic, molecular, biochemical and cell biological features which contribute to this pathology. Furthermore, findings have indicated that single and/or multiple haploinsufficiency for various genes involved in DNA repair and cell cycle checkpoint control, such as Atm, Brca1 or Rad9, influence cataract development and thus radiosensitivity. These observations have direct applicability to various human populations including accidentally exposed individuals, interventional medical workers, astronauts and nuclear plant workers.

  4. SU-E-T-495: Neutron Induced Electronics Failure Rate Analysis for a Single Room Proton Accelerator

    SciTech Connect (OSTI)

    Knutson, N; DeWees, T; Klein, E

    2014-06-01

    Purpose: To determine the failure rate as a function of neutron dose of the range modulator's servo motor controller system (SMCS) while shielded with Borated Polyethylene (BPE) and unshielded in a single room proton accelerator. Methods: Two experimental setups were constructed using two servo motor controllers and two motors. Each SMCS was then placed 30 cm from the end of the plugged proton accelerator applicator. The motor was then turned on and observed from outside of the vault while being irradiated to known neutron doses determined from bubble detector measurements. Anytime the motor deviated from the programmed motion a failure was recorded along with the delivered dose. The experiment was repeated using 9 cm of BPE shielding surrounding the SMCS. Results: Ten SMCS failures were recorded in each experiment. The dose per monitor unit for the unshielded SMCS was 0.0211 mSv/MU and 0.0144 mSv/MU for the shielded SMCS. The mean dose to produce a failure for the unshielded SMCS was 63.5 58.3 mSv versus 17.0 12.2 mSv for the shielded. The mean number of MUs between failures were 2297 1891 MU for the unshielded SMCS and 2122 1523 MU for the shielded. A Wilcoxon Signed Ranked test showed the dose between failures were significantly different (P value = 0.044) while the number of MUs between failures were not (P value = 1.000). Statistical analysis determined a SMCS neutron dose of 5.3 mSv produces a 5% chance of failure. Depending on the workload and location of the SMCS, this failure rate could impede clinical workflow. Conclusion: BPE shielding was shown to not reduce the average failure of the SMCS and relocation of the system outside of the accelerator vault was required to lower the failure rate enough to avoid impeding clinical work flow.

  5. Energy Differential Response of Cancer Cells for Low Dose Irradiation:Impact of Monoenergetic Brachytherapy Sources

    SciTech Connect (OSTI)

    Gueye, Paul; Prilepskiy, Yuriy; Keppel, Cynthia; Britten, R.

    2010-06-01

    Purpose: The purpose of this work was to evaluate the energy differential response of cancer cells under identical dose exposure to asses the relevancy of mono-energetic sources for Brachytherapy treatments. Method and Materials: An electron energy spectrum impinging on lived breast cancer cell lines (MDA321) was obtained by placing a 19.65 {micro}Ci {sup 90}Sr/{sup 90}Y radioactive source in front of a non-uniform magnetic field constructed from two 5.08 x 5.0 cm x 2.54 cm neodimium ion permanent dipole magnets with a 1 cm separation gap. The cell lines were placed on the exit pole face of the magnet and were subsequently irradiated with different electron energies ranging from about 0.75 MeV to 1.85 MeV. The energy distribution was accurately measured with a scintillating fiber detector system that provided a 0.5% agreement with ICRU and a 5% energy resolution. The dosimetry was performed using a series of data acquired with a {sup 9}Sr/{sup 90}Y 4.5 mCi SIA-6 eye applicator, 6-21 MeV fixed energies from a Varian 2100 EX linac, EBT Gafchromic and Kodak ERT2 films, and an ion chamber detector. The accuracy of the dose rate obtained at different locations along and away from the magnet inside the cell containers was within 10.7%. Results: The cell lines were irradiated with a 0.5-4 Gy dose range. The data indicate a very strong differential energy response for electrons around 1 MeV (more lethal) compare to those with lesser or greater energy and a survival rate of at most 10% at very low dose (0.5-2 Gy). Conclusion: Mono-energetic Brachytherapy sources may provide a new pathway for radio-therapy treatment optimizations following a dedicated study showing very unusual high lethality in a specific energy window for MDA321 breast cancer cells.

  6. SU-E-T-105: Development of 3D Dose Verification System for Volumetric Modulated Arc Therapy Using Improved Polyacrylamide-Based Gel Dosimeter

    SciTech Connect (OSTI)

    Ono, K; Fujimoto, S; Akagi, Y; Hirokawa, Y; Hayashi, S; Miyazawa, M

    2014-06-01

    Purpose: The aim of this dosimetric study was to develop 3D dose verification system for volumetric modulated arc therapy (VMAT) using polyacrylamide-based gel (PAGAT) dosimeter improved the sensitivity by magnesium chloride (MgCl{sub 2}). Methods: PAGAT gel containing MgCl{sub 2} as a sensitizer was prepared in this study. Methacrylic-acid-based gel (MAGAT) was also prepared to compare the dosimetric characteristics with PAGAT gel. The cylindrical glass vials (4 cm diameter, 12 cm length) filled with each polymer gel were irradiated with 6 MV photon beam using Novalis Tx linear accelerator (Varian/BrainLAB). The irradiated polymer gel dosimeters were scanned with Signa 1.5 T MRI system (GE), and dose calibration curves were obtained using T{sub 2} relaxation rate (R{sub 2} = 1/T{sub 2}). Dose rate (100-600 MU min{sup ?1}) and fractionation (1-8 fractions) were varied. In addition, a cubic acrylic phantom (10 10 10 cm{sup 3}) filled with improved PAGAT gel inserted into the IMRT phantom (IBA) was irradiated with VMAT (RapidArc). C-shape structure was used for the VMAT planning by the Varian Eclipse treatment planning system (TPS). The dose comparison of TPS and measurements with the polymer gel dosimeter was accomplished by the gamma index analysis, overlaying the dose profiles for a set of data on selected planes using in-house developed software. Results: Dose rate and fractionation dependence of improved PAGAT gel were smaller than MAGAT gel. A high similarity was found by overlaying the dose profiles measured with improved PAGAT gel dosimeter and the TPS dose, and the mean pass rate of the gamma index analysis using 3%/3 mm criteria was achieved 90% on orthogonal planes for VMAT using improved PAGAT gel dosimeter. Conclusion: In-house developed 3D dose verification system using improved polyacrylamide-based gel dosimeter had a potential as an effective tool for VMAT QA.

  7. SU-F-BRE-06: Evaluation of Patient CT Dose Reconstruction From 3D Diode Array Measurements Using Anthropomorphic Phantoms

    SciTech Connect (OSTI)

    Huang, M; Benhabib, S; Cardan, R; Brezovich, I; Popple, R; Faught, A; Followill, D

    2014-06-15

    Purpose: To compare 3D reconstructed dose of IMRT plans from 3D diode array measurements with measurements in anthropomorphic phantoms. Methods: Six IMRT plans were created for the IROC Houston (RPC) head and neck (H and N) and lung phantoms following IROC Houston planning protocols. The plans included flattened and unflattened beam energies ranging from 6 MV to 15 MV and both static and dynamic MLC tecH and Niques. Each plan was delivered three times to the respective anthropomorphic phantom, each of which contained thermoluminescent dosimeters (TLDs) and radiochromic films (RCFs). The plans were also delivered to a Delta4 diode array (Scandidos, Uppsala, Sweden). Irradiations were done using a TrueBeam STx (Varian Medical Systems, Palo Alto, CA). The dose in the patient was calculated by the Delta4 software, which used the diode measurements to estimate incident energy fluence and a kernel-based pencil beam algorithm to calculate dose. The 3D dose results were compared with the TLD and RCF measurements. Results: In the lung, the average difference between TLDs and Delta4 calculations was 5% (range 2%7%). For the H and N, the average differences were 2.4% (range 0%4.5%) and 1.1% (range 0%2%) for the high- and low-dose targets, respectively, and 12% (range 10%-13%) for the organ-at-risk simulating the spinal cord. For the RCF and criteria of 7%/4mm, 5%/3mm, and 3%/3mm, the average gamma-index pass rates were 95.4%, 85.7%, and 76.1%, respectively for the H and N and 76.2%, 57.8%, and 49.5% for the lung. The pass-rate in the lung decreased with increasing beam energy, as expected for a pencil beam algorithm. Conclusion: The H and N phantom dose reconstruction met the IROC Houston acceptance criteria for clinical trials; however, the lung phantom dose did not, most likely due to the inaccuracy of the pencil beam algorithm in the presence of low-density inhomogeneities. Work supported by PHS grant CA10953 and CA81647 (NCI, DHHS)

  8. Mean glandular dose in a breast screening programme

    SciTech Connect (OSTI)

    Galvan, H. A.; Perez-Badillo, M. P.; Villasenor, Y.

    2012-10-23

    Breast density has an important role in early detection of breast cancer, because has been reported the strong association between breast density and invasive breast cancer risk. Mammography is the gold standard to early detection of breast cancer, despite of this require ionizing radiation that may increase radio-induced cancer risk. This maybe limited with a quality control programme of mammographic units, with the main goal of achieving high quality images with low radiation dose. International Atomic Energy Agency (IAEA) published in 2011 the {sup Q}uality assurance programme for digital mammography{sup ,} where glandular tissue quantity is an important parameter to compute mean glandular dose (MGD), which is necessary to reduce its associated risk. In this work we show the first results in our country applying this protocol and studying breast density in a small group. MGD complies with national and IAEA dose limits.

  9. Dose homogeneity specification for reference dosimetry of nonstandard fields

    SciTech Connect (OSTI)

    Chung, Eunah; Soisson, Emilie; Seuntjens, Jan [Medical Physics Unit, McGill University, Montreal General Hospital (L5-113), 1650 Cedar Avenue, Montreal, Quebec H3G 1A4 (Canada); Medical Physics Unit, McGill University and Department of Medical Physics, McGill University Health Centre, Montreal General Hospital (L5-113), 1650 Cedar Avenue, Montreal, Quebec H3G 1A4 (Canada); Medical Physics Unit, McGill University, Montreal General Hospital (L5-113), 1650 Cedar Avenue, Montreal, Quebec H3G 1A4 (Canada)

    2012-01-15

    Purpose: To investigate the sensitivity of the plan-class specific correction factor to dose distributions in composite nonstandard field dosimetry. Methods: A cylindrical water-filled PMMA phantom was constructed at the center of which reference absorbed dose could be measured. Ten different TomoTherapy-based IMRT fields were created on the CT images of the phantom. The dose distribution for each IMRT field was estimated at the position of a radiation detector or ionization chamber. The dose in each IMRT field normalized to that in a reference 10 x 10 cm{sup 2} field was measured using a PTW micro liquid ion chamber. Based on the new dosimetry formalism, a plan-class specific correction factor k{sub Q{sub p{sub c{sub s{sub r,Q}{sup f{sub p}{sub c}{sub s}{sub r},f{sub r}{sub e}{sub f}}}}}} for each field was measured for two Farmer-type chambers, Exradin A12 and NE2571, as well as for a smaller Exradin A1SL chamber. The dependence of the measured correction factor on parameters characterizing dose distribution was analyzed. Results: Uncertainty on the plan-class specific correction factor measurement was in the range of 0.3%-0.5% and 0.3%-0.8% for the Farmer-type chambers and the Exradin A1SL, respectively. When the heterogeneity of the central region of the target volume was less than 5%, the correction factor did not differ from unity by more than 0.7% for the three air-filled ionization chambers. For more heterogeneous dose deliveries, the correction factor differed from unity by up to 2.4% for the Farmer-type chambers. For the Exradin A1SL, the correction factor was closer to unity due to the reduced effect of dose gradients, while it was highly variable in different IMRT fields because of a more significant impact of positioning uncertainties on the response of this chamber. Conclusions: The authors have shown that a plan-class specific correction factor can be specified as a function of plan evaluation parameters especially for Farmer-type chambers. This work provides a recipe based on quantifying dose distribution to accurately select air-filled ionization chamber correction factors for nonstandard fields.

  10. Analysis Approach and Data Package for Mayak Public Doses

    SciTech Connect (OSTI)

    Eslinger, Paul W.; Napier, Bruce A.

    2013-09-18

    Historical activities at facilities producing nuclear materials for weapons released radioactivity into the air and water. Past studies in the United States have evaluated the release, atmospheric transport and environmental accumulation of 131I from the nuclear facilities at Hanford in Washington State and the resulting dose to members of the public (Farris et al. 1994). A multi-year dose reconstruction effort (Mokrov et al. 2004) is also being conducted to produce representative dose estimates for members of the public living near Mayak, Russia, from atmospheric releases of 131I at the facilities of the Mayak Production Association. The approach to calculating individual doses to members of the public from historical releases of airborne 131I has the following general steps: Construct estimates of releases 131I to the air from production facilities. Model the transport of 131I in the air and subsequent deposition on the ground and vegetation. Model the accumulation of 131I in soil, water and food products (environmental media). Calculate the dose for an individual by matching the appropriate lifestyle and consumption data for the individual to the concentrations of 131I in environmental media at their residence location. A number of computer codes were developed to facilitate the study of airborne 131I emissions at Hanford. Of particular interest is DESCARTES code that modeled accumulation of 131I in environmental media (Miley et al. 1994). In addition, the CIDER computer code estimated annual doses to individuals (Eslinger et al. 1994) using the equations and parameters specific to Hanford (Snyder et al. 1994). Several of the computer codes developed to model 131I releases from Hanford are general enough to be used for other facilities. Additional codes have been developed, including the new individual dose code CiderF (Eslinger and Napier 2013), and applied to historical releases of 131I from Mayak. This document provides a data package that identifies computer code runs and associated input and output files prepared for the purpose of calculating doses to members of the public from atmospheric releases of 131I at the Mayak Production Association for the time period 1948 through 1972.

  11. Measurements of radiation doses induced by high intensity laser between

    Office of Scientific and Technical Information (OSTI)

    10^16 and 10^21 w/cm^2 onto solid targets at LCLS MEC instrument (Conference) | SciTech Connect SciTech Connect Search Results Conference: Measurements of radiation doses induced by high intensity laser between 10^16 and 10^21 w/cm^2 onto solid targets at LCLS MEC instrument Citation Details In-Document Search Title: Measurements of radiation doses induced by high intensity laser between 10^16 and 10^21 w/cm^2 onto solid targets at LCLS MEC instrument Authors: Liang, T. ; /SLAC /Georgia Tech

  12. Measurements of radiation doses induced by high intensity laser between

    Office of Scientific and Technical Information (OSTI)

    10^16 and 10^21 w/cm^2 onto solid targets at LCLS MEC instrument (Conference) | SciTech Connect Conference: Measurements of radiation doses induced by high intensity laser between 10^16 and 10^21 w/cm^2 onto solid targets at LCLS MEC instrument Citation Details In-Document Search Title: Measurements of radiation doses induced by high intensity laser between 10^16 and 10^21 w/cm^2 onto solid targets at LCLS MEC instrument × You are accessing a document from the Department of Energy's (DOE)

  13. Out-of-field organ doses and associated radiogenic risks from para-aortic radiotherapy for testicular seminoma

    SciTech Connect (OSTI)

    Mazonakis, Michalis Berris, Theocharis; Damilakis, John; Varveris, Charalambos; Lyraraki, Efrossyni

    2014-05-15

    Purpose: The aims of this study were to (a) calculate the radiation dose to out-of-field organs from radiotherapy for stage I testicular seminoma and (b) estimate the associated radiogenic risks. Methods: Monte Carlo methodology was employed to model radiation therapy with typical anteroposterior and posteroanterior para-aortic fields on an anthropomorphic phantom simulating an average adult. The radiation dose received by all main and remaining organs that defined by the ICRP publication 103 and excluded from the treatment volume was calculated. The effect of field dimensions on each organ dose was determined. Additional therapy simulations were generated by introducing shielding blocks to protect the kidneys from primary radiation. The gonadal dose was employed to assess the risk of heritable effects for irradiated male patients of reproductive potential. The lifetime attributable risks (LAR) of radiotherapy-induced cancer were estimated using gender- and organ-specific risk coefficients for patient ages of 20, 30, 40, and 50 years old. The risk values were compared with the respective nominal risks. Results: Para-aortic irradiation to 20 Gy resulted in out-of-field organ doses of 5.0538.6 mGy. Blocked field treatment led to a dose change up to 28%. The mean organ dose variation by increasing or decreasing the applied field dimensions was 18.7% 3.9% and 20.8% 4.5%, respectively. The out-of-field photon doses increased the lifetime intrinsic risk of developing thyroid, lung, bladder, prostate, and esophageal cancer by (0.11.4)%, (0.41.1)%, (2.55.4)%, (0.20.4)%, and (6.49.2)%, respectively, depending upon the patient age at exposure and the field size employed. A low risk for heritable effects of less than 0.029% was found compared with the natural incidence of these defects. Conclusions: Testicular cancer survivors are subjected to an increased risk for the induction of bladder and esophageal cancer following para-aortic radiotherapy. The probability for the appearance of any other malignant disease to out-of-field organs was slightly elevated in respect to the nominal cancer incidence rates.

  14. 2014-2015 Power Rate Schedules

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

    4 Power Rate Schedules and General Rate Schedule Provisions (FY 2014-2015) October 2013 United States Department of Energy Bonneville Power Administration 905 N.E. 11th Avenue...

  15. Energy Efficiency Interest Rate Reduction Program

    Broader source: Energy.gov [DOE]

    For new and existing home purchases that are rated 6 Star or 5 Star Plus, applicants are eligible for an interest rate reduction for the first $200,000 of the loan amount, with a blended interest...

  16. Utility Rate | OpenEI Community

    Open Energy Info (EERE)

    Rate > Posts by term > Utility Rate Content Group Activity By term Q & A Feeds Term: American Clean Skies Foundation Type Term Title Author Replies Last Post sort icon Blog entry...

  17. Utility Rate | OpenEI Community

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    Utility Rate Home > Groups > Groups > Utility Rate Content Group Activity By term Q & A Feeds There are no feeds from external sites for this group. Groups Menu You must login in...

  18. Category:Utility Rates | Open Energy Information

    Open Energy Info (EERE)

    Rates Jump to: navigation, search Add a new Utility Rate This category currently contains no pages or media. Retrieved from "http:en.openei.orgwindex.php?titleCategory:Utility...

  19. Residential Solar Valuation Rates | Department of Energy

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

    Residential Solar Valuation Rates Residential Solar Valuation Rates This presentation summarizes the information discussed by Rabago Energy during the Best Practices in the Design of Utility Solar Programs Webinar on Sept. 27, 2012. PDF icon utility_design_rabago_energy.pdf More Documents & Publications Austin Energy's Residential Solar Rate QER - Comment of Energy Innovation 1 QER - Comment of Energy Innovation 8

  20. Evaluation of Radiation Doses Due to Consumption of Contaminated Food Items and Calculation of Food Class-Specific Derived Intervention Levels

    SciTech Connect (OSTI)

    Heinzelman, K M; Mansfield, W G

    2010-04-27

    This document evaluates the expected radiation dose due to the consumption of several specific food classes (dairy, meat, produce, etc.) contaminated with specific radionuclides, and relates concentration levels in food to the detection abilities of typical aboratory analysis/measurement methods. The attached charts present the limiting organ dose as a function of the radionuclide concentration in a particular food class, and allow the user to compare these concentrations and doses to typical analytical detection apabilities. The expected radiation dose depends on several factors: the age of the individual; the radionuclide present in the food; the concentration of the radionuclide in the food; and the amount of food consumed. Food consumption rates for individuals of various ges were taken from the 1998 United States Food and Drug Administration (FDA) document, Accidental Radioactive Contamination of HUman Food and Animal Feeds: Recommendations for State and Local Agencies. In that document, the FDA defines the erived Intervention Level (DIL), which is the concentration of a particular radionuclide in food that if consumed could result in an individual receiving a radiation dose exceeding the Protection Action Guide (PAG) thresholds for intervention. This document also resents odified, food class specific DIL, which is calculated using a somewhat modified version of the FDA's procedure. This document begins with an overview of the FDA's DIL calculation, followed by a description of the food class specific DIL calculations, and finally charts of the radiation dose per radioactivity concentration for several food class/radionuclide combinations.

  1. Hysterosalpingography using a flat panel unit: Evaluation and optimization of ovarian radiation dose

    SciTech Connect (OSTI)

    Messaris, Gerasimos A. T.; Abatzis, Ilias; Kagadis, George C.; Samartzis, Alexandros P.; Athanasopoulou, Panagiota; Christeas, Nikolaos; Katsanos, Konstantinos; Karnabatidis, Dimitrios; Nikiforidis, George C.

    2012-07-15

    Purpose: The aim of the present study was the evaluation and optimization of radiation dose to the ovaries (D) in hysterosalpingography (HSG). Methods: The study included a phantom study and a clinical one. In the phantom study, we evaluated imaging results for different geometrical setups and irradiation conditions. In the clinical study, 34 women were assigned into three different fluoroscopy modes and D was estimated with direct cervical TLD measurements. Results: In the phantom study, we used a source-to-image-distance (SID) of 110 cm and a field diagonal of 48 cm, and thus decreased air KERMA rate (KR) by 19% and 70%, respectively, for beam filtration: 4 mm Al and 0.9 mm Cu (Low dose). The least radiation exposure was accomplished by using the 3.75 pps fluoroscopy mode in conjunction with beam filtration: Low dose. In the clinical study, D normalized to 50 s of fluoroscopy time with a 3.75 pps fluoroscopy mode reached a value of 0.45 {+-} 0.04 mGy. Observers' evaluation of diagnostic image quality did not significantly differ for the three different modes of acquisition that were compared. Conclusions: Digital spot radiographs could be omitted in modern flat panel systems during HSG. Fluoroscopy image acquisitions in a modern flat panel unit at 3.75 pps and a beam filtration of 4 mm Al and 0.9 mm Cu demonstrate acceptable image quality with an average D equal to 0.45 mGy. This value is lower compared to the studied literature. For these reasons, the proposed method may be recommended for routine HSG examination in order to limit radiation exposure to the ovaries.

  2. Method for preparing dosimeter for measuring skin dose

    DOE Patents [OSTI]

    Jones, Donald E. (Idaho Falls, ID); Parker, DeRay (Idaho Falls, ID); Boren, Paul R. (Idaho Falls, ID)

    1982-01-01

    A personnel dosimeter includes a plurality of compartments containing thermoluminescent dosimeter phosphors for registering radiation dose absorbed in the wearer's sensitive skin layer and for registering more deeply penetrating radiation. Two of the phosphor compartments communicate with thin windows of different thicknesses to obtain a ratio of shallowly penetrating radiation, e.g. beta. A third phosphor is disposed within a compartment communicating with a window of substantially greater thickness than the windows of the first two compartments for estimating the more deeply penetrating radiation dose. By selecting certain phosphors that are insensitive to neutrons and by loading the holder material with neutron-absorbing elements, energetic neutron dose can be estimated separately from other radiation dose. This invention also involves a method of injection molding of dosimeter holders with thin windows of consistent thickness at the corresponding compartments of different holders. This is achieved through use of a die insert having the thin window of precision thickness in place prior to the injection molding step.

  3. Dosimeter for measuring skin dose and more deeply penetrating radiation

    DOE Patents [OSTI]

    Jones, Donald E. (Idaho Falls, ID); Parker, DeRay (Idaho Falls, ID); Boren, Paul R. (Idaho Falls, ID)

    1981-01-01

    A personnel dosimeter includes a plurality of compartments containing thermoluminescent dosimeter phosphors for registering radiation dose absorbed in the wearer's sensitive skin layer and for registering more deeply penetrating radiation. Two of the phosphor compartments communicate with thin windows of different thicknesses to obtain a ratio of shallowly penetrating radiation, e.g. beta. A third phosphor is disposed within a compartment communicating with a window of substantially greater thickness than the windows of the first two compartments for estimating the more deeply penetrating radiation dose. By selecting certain phosphors that are insensitive to neutrons and by loading the holder material with netruon-absorbing elements, energetic neutron dose can be estimated separately from other radiation dose. This invention also involves a method of injection molding of dosimeter holders with thin windows of consistent thickness at the corresponding compartments of different holders. This is achieved through use of a die insert having the thin window of precision thickness in place prior to the injection molding step.

  4. Predicting Pneumonitis Risk: A Dosimetric Alternative to Mean Lung Dose

    SciTech Connect (OSTI)

    Tucker, Susan L.; Mohan, Radhe; Liengsawangwong, Raweewan; Martel, Mary K.; Liao Zhongxing

    2013-02-01

    Purpose: To determine whether the association between mean lung dose (MLD) and risk of severe (grade {>=}3) radiation pneumonitis (RP) depends on the dose distribution pattern to normal lung among patients receiving 3-dimensional conformal radiation therapy for non-small-cell lung cancer. Methods and Materials: Three cohorts treated with different beam arrangements were identified. One cohort (2-field boost [2FB]) received 2 parallel-opposed (anteroposterior-posteroanterior) fields per fraction initially, followed by a sequential boost delivered using 2 oblique beams. The other 2 cohorts received 3 or 4 straight fields (3FS and 4FS, respectively), ie, all fields were irradiated every day. The incidence of severe RP was plotted against MLD in each cohort, and data were analyzed using the Lyman-Kutcher-Burman (LKB) model. Results: The incidence of grade {>=}3 RP rose more steeply as a function of MLD in the 2FB cohort (N=120) than in the 4FS cohort (N=138), with an intermediate slope for the 3FS group (N=99). The estimated volume parameter from the LKB model was n=0.41 (95% confidence interval, 0.15-1.0) and led to a significant improvement in fit (P=.05) compared to a fit with volume parameter fixed at n=1 (the MLD model). Unlike the MLD model, the LKB model with n=0.41 provided a consistent description of the risk of severe RP in all three cohorts (2FB, 3FS, 4FS) simultaneously. Conclusions: When predicting risk of grade {>=}3 RP, the mean lung dose does not adequately take into account the effects of high doses. Instead, the effective dose, computed from the LKB model using volume parameter n=0.41, may provide a better dosimetric parameter for predicting RP risk. If confirmed, these findings support the conclusion that for the same MLD, high doses to small lung volumes ('a lot to a little') are worse than low doses to large volumes ('a little to a lot').

  5. Steady-state, high-dose neutron generation and concentration apparatus and method for deuterium atoms

    SciTech Connect (OSTI)

    Uhm, H.S.; Lee, W.M.

    1991-01-01

    A steady-state source of neutrons is produced within an electrically grounded and temperature controlled chamber confining tritium or deuterium plasma at a predetermined density to effect implantation of ions in the surface of a palladium target rod coated with diffusion barrier material and immersed in such plasma. The rod is enriched with a high concentration of deuterium atoms after a prolonged plasma ion implantation. Collision of the deuterium atoms in the target by impinging ions of the plasma initiates fusion reactions causing emission of neutrons during negative voltage pulses applied to the rod through a high power modulator. The neutrons are so generated at a relatively high dose rate under optimized process conditions.

  6. Hypopharyngeal Dose Is Associated With Severe Late Toxicity in Locally Advanced Head-and-Neck Cancer: An RTOG Analysis

    SciTech Connect (OSTI)

    Machtay, Mitchell; Moughan, Jennifer; Farach, Andrew; University of Texas Health Science Center Martin-O'Meara, Elizabeth; Galvin, James; Thomas Jefferson University, Philadelphia, Pennsylvania ; Garden, Adam S.; Weber, Randal S.; Cooper, Jay S.; Forastiere, Arlene; Ang, K. Kian

    2012-11-15

    Purpose: Concurrent chemoradiation therapy (CCRT) for squamous cell carcinoma of the head and neck (SCCHN) increases local tumor control but at the expense of increased toxicity. We recently showed that several clinical/pretreatment factors were associated with the occurrence of severe late toxicity. This study evaluated the potential relationship between radiation dose delivered to the pharyngeal wall and toxicity. Methods and Materials: This was an analysis of long-term survivors from 3 previously reported Radiation Therapy Oncology Group (RTOG) trials of CCRT for locally advanced SCCHN (RTOG trials 91-11, 97-03, and 99-14). Severe late toxicity was defined in this secondary analysis as chronic grade 3-4 pharyngeal/laryngeal toxicity and/or requirement for a feeding tube {>=}2 years after registration and/or potential treatment-related death (eg, pneumonia) within 3 years. Radiation dosimetry (2-dimensional) analysis was performed centrally at RTOG headquarters to estimate doses to 4 regions of interest along the pharyngeal wall (superior oropharynx, inferior oropharynx, superior hypopharynx, and inferior hypopharynx). Case-control analysis was performed with a multivariate logistic regression model that included pretreatment and treatment potential factors. Results: A total of 154 patients were evaluable for this analysis, 71 cases (patients with severe late toxicities) and 83 controls; thus, 46% of evaluable patients had a severe late toxicity. On multivariate analysis, significant variables correlated with the development of severe late toxicity, including older age (odds ratio, 1.062 per year; P=.0021) and radiation dose received by the inferior hypopharynx (odds ratio, 1.023 per Gy; P=.016). The subgroup of patients receiving {<=}60 Gy to the inferior hypopharynx had a 40% rate of severe late toxicity compared with 56% for patients receiving >60 Gy. Oropharyngeal dose was not associated with this outcome. Conclusions: Severe late toxicity following CCRT is common in long-term survivors. Age is the most significant factor, but hypopharyngeal dose also was associated.

  7. Brachial Plexus-Associated Neuropathy After High-Dose Radiation Therapy for Head-and-Neck Cancer

    SciTech Connect (OSTI)

    Chen, Allen M.; Hall, William H.; Li, Judy; Beckett, Laurel; Farwell, D. Gregory; Lau, Derick H.; Purdy, James A.

    2012-09-01

    Purpose: To identify clinical and treatment-related predictors of brachial plexus-associated neuropathies after radiation therapy for head-and-neck cancer. Methods and Materials: Three hundred thirty patients who had previously completed radiation therapy for head-and-neck cancer were prospectively screened using a standardized instrument for symptoms of neuropathy thought to be related to brachial plexus injury. All patients were disease-free at the time of screening. The median time from completion of radiation therapy was 56 months (range, 6-135 months). One-hundred fifty-five patients (47%) were treated by definitive radiation therapy, and 175 (53%) were treated postoperatively. Radiation doses ranged from 50 to 74 Gy (median, 66 Gy). Intensity-modulated radiation therapy was used in 62% of cases, and 133 patients (40%) received concurrent chemotherapy. Results: Forty patients (12%) reported neuropathic symptoms, with the most common being ipsilateral pain (50%), numbness/tingling (40%), motor weakness, and/or muscle atrophy (25%). When patients with <5 years of follow-up were excluded, the rate of positive symptoms increased to 22%. On univariate analysis, the following factors were significantly associated with brachial plexus symptoms: prior neck dissection (p = 0.01), concurrent chemotherapy (p = 0.01), and radiation maximum dose (p < 0.001). Cox regression analysis confirmed that both neck dissection (p < 0.001) and radiation maximum dose (p < 0.001) were independently predictive of symptoms. Conclusion: The incidence of brachial plexus-associated neuropathies after radiation therapy for head-and-neck cancer may be underreported. In view of the dose-response relationship identified, limiting radiation dose to the brachial plexus should be considered when possible.

  8. Irradiation dose and temperature dependence of fracture toughness in high dose HT9 steel from the fuel duct of FFTF

    SciTech Connect (OSTI)

    Byun, Thak Sang; Toloczko, Mychailo B.; Saleh, Tarik A.; Maloy, Stuart A.

    2013-01-14

    To expand the knowledge base for fast reactor core materials, fracture toughness has been evaluated for high dose HT9 steel using miniature disk compact tension (DCT) specimens. The HT9 steel DCT specimens were machined from the ACO-3 fuel duct of the Fast Flux Test Facility (FFTF), which achieved high doses in the range of 3148 dpa at 378504 C. The static fracture resistance (J-R) tests have been performed in a servohydraulic testing machine in vacuum at selected temperatures including room temperature, 200 C, and each irradiation temperature. Brittle fracture with a low toughness less than 50 MPa pm occurred in room temperature tests when irradiation temperature was below 400 C, while ductile fracture with stable crack growth was observed when irradiation temperature was higher. No fracture toughness less than 100 MPa pm was measured when the irradiation temperature was above 430 C. It was shown that the influence of irradiation temperature was dominant in fracture toughness while the irradiation dose has only limited influence over the wide dose range 3148 dpa. A slow decrease of fracture toughness with test temperature above room temperature was observed for the nonirradiated and high temperature (>430 *C) irradiation cases, which indicates that the ductilebrittle transition temperatures (DBTTs) in those conditions are lower than room temperature. A comparison with the collection of existing data confirmed the dominance of irradiation temperature in the fracture toughness of HT9 steels.

  9. SU-E-J-158: Experimental Investigation of Proton Radiography Based On Time-Resolved Dose Measurements

    SciTech Connect (OSTI)

    Testa, M; Paganetti, H; Lu, H-M; Doolan, P; H, Bentefour E

    2014-06-01

    Purpose: To use proton radiography for i) in-vivo range verification of the brain fields of medulloblastoma patients in order to reduce the exit dose to the cranial skin and thus the risk of permanent alopecia; ii) for performing patient specific optimization of the calibration from CT-Hounsfield units to proton relative stopping power in order to minimize uncertainties of proton rang Methods: We developed and tested a prototype proton radiography system based on a single-plane scintillation screen coupled with a fast CCD camera (1ms sampling rate, 0.29x0.29 mm{sup 2} pixel size, 3030 cm{sup 2} field of view). The method is based on the principle that, for passively scattered beams, the radiological depth of any point in the plateau of a spread-out Bragg-Peak (SOBP) can be inferred from the time-pattern of the dose rate measurements. We performed detector characterization measurements using complex-shape homogeneous phantoms and an Alderson phanto Results: Detector characterization tests confirmed the robustness of the technique. The results of the phantom measurements are encouraging in terms of achievable accuracy of the water equivalent thickness. A technique to minimize the degradation of spatial resolution due to multiple Coulomb scattering is discussed. Our novel radiographic technique is rapid (100 ms) and simultaneous over the whole field. The dose required to produce one radiograph, with the current settings, is ?3 cG Conclusion: The results obtained with this simple and innovative radiography method are promising and motivate further development of technique. The system requires only a single-plane 2D dosimeter and it uses the clinical beam for a fraction of second with low dose to the patient.

  10. Isotoxic Dose Escalation in the Treatment of Lung Cancer by Means of Heterogeneous Dose Distributions in the Presence of Respiratory Motion

    SciTech Connect (OSTI)

    Baker, Mariwan; Nielsen, Morten [Laboratory of Radiation Physics, Odense University Hospital, Odense (Denmark); Hansen, Olfred [Department of Oncology, Odense University Hospital, Odense (Denmark); Jahn, Jonas Westberg [Laboratory of Radiation Physics, Odense University Hospital, Odense (Denmark); Korreman, Stine [Department of Radiation Oncology, Copenhagen University Hospital, Copenhagen (Denmark); Brink, Carsten, E-mail: carsten.brink@ouh.regionsyddanmark.dk [Laboratory of Radiation Physics, Odense University Hospital, Odense (Denmark); Institute of Clinical Research, University of Southern Denmark, Odense (Denmark)

    2011-11-01

    Purpose: To test, in the presence of intrafractional respiration movement, a margin recipe valid for a homogeneous and conformal dose distribution and to test whether the use of smaller margins combined with heterogeneous dose distributions allows an isotoxic dose escalation when respiratory motion is considered. Methods and Materials: Twenty-three Stage II-III non-small-cell lung cancer patients underwent four-dimensional computed tomography scanning. The gross tumor volume and clinical target volume (CTV) were outlined in the mid-ventilation phase. The CTV-to-planning target volume (PTV) margin was calculated by use of a standard margin recipe and the patient-specific respiration pattern. Standard three-dimensional treatment plans were generated and recalculated on the remaining respiration phases. The planning was repeated for a CTV-to-PTV margin decreased by 2.5 and 5 mm relative to the initial margin in all directions. Time-averaged dose-volume histograms (four-dimensional dose-volume histograms) were calculated to evaluate the CTV-to-PTV margin. Finally, the dose was escalated in the plans with decreased PTV such that the mean lung dose (predictor of radiation-induced pneumonitis) was equal to mean lung dose in the plan by use of the initially calculated margin. Results: A reduction of the standard margin by 2.5 mm compared with the recipe resulted in too low of a minimum dose for some patients. A combination of dose escalation and use of heterogeneous dose distribution was able to increase the minimum dose to the target by approximately 10% and 20% for a CTV-to-PTV margin reduction of 2.5 mm and 5.0 mm, respectively. Conclusion: The margin recipe is valid for intrafractional respiration-induced tumor motions. It is possible to increase the dose to the target without increased mean lung dose with an inhomogeneous dose distribution.

  11. Kilovoltage cone-beam CT imaging dose during breast radiotherapy: A dose comparison between a left and right breast setup

    SciTech Connect (OSTI)

    Quinn, Alexandra; Holloway, Lois; Begg, Jarrad; Nelson, Vinod; Metcalfe, Peter

    2014-07-01

    The purpose of this study was to investigate the delivered dose from a kilovoltage cone-beam computed tomography (kV-CBCT) acquired in breast treatment position for a left and right breast setup. The dose was measured with thermoluminescent dosimeters positioned within a female anthropomorphic phantom at organ locations. Imaging was performed on an Elekta Synergy XVI system with the phantom setup on a breast board. The image protocol involved 120 kVp, 140 mAs, and a 270 arc rotation clockwise 0 to 270 for the left breast setup and 270 to 180 for the right breast setup (maximum arc rotations possible). The dose delivered to the left breast, right breast, and heart was 5.1 mGy, 3.9 mGy, and 4.0 mGy for the left breast setup kV-CBCT, and 6.4 mGy, 6.0 mGy, and 4.8 mGy for the right breast setup kV-CBCT, respectively. The rotation arc of the kV-CBCT influenced the dose delivered, with the right breast setup kV-CBCT found to deliver a dose of up to 4 mGy or 105% higher to the treated breast?s surface in comparison with the left breast setup. This is attributed to the kV-CBCT source being more proximal to the anterior of the phantom for a right breast setup, whereas the source is more proximal to the posterior of the patient for a left-side scan.

  12. Public Utilities Specialist (Rates) | Department of Energy

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

    Public Utilities Specialist (Rates) Public Utilities Specialist (Rates) Submitted by admin on Fri, 2016-01-08 00:16 Job Summary Organization Name Department Of Energy Agency SubElement Western Area Power Administration Locations Phoenix, Arizona Announcement Number WAPA-16-DE-70 Job Summary (See Frequently Asked Questions for more information). Where would I be working? Western Area Power Administration, Desert Southwest Region, Power Marketing, Rates and Alternative Financing, Phoenix, AZ

  13. NREL: Photovoltaics Research - Photovoltaic Energy Ratings Methods

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

    Validation Photovoltaic Energy Ratings Methods Validation The Photovoltaic (PV) Engineering group at NREL validates energy ratings methods by standards committees to establish an energy rating methodology. We are evaluating techniques to account for the impact on PV performance from variations in the spectral distribution of solar radiation. Two types of methods were evaluated for correcting the short-circuit current of PV modules for variations in the solar spectrum under clear skies: (1)

  14. OpenEI Community - utility rate

    Open Energy Info (EERE)

    title"" >After several months of development and testing, the next generation web service for the utility rate database is finally here I encourage you to check out...

  15. CM-1-H Wholesale Power Rate Schedule

    Broader source: Energy.gov [DOE]

    Availability:This rate schedule shall be available to the South Mississippi Electric Power Association, Municipal Energy Agency of Mississippi, and Mississippi Delta Energy Agency (hereinafter...

  16. Method of controlling fusion reaction rates

    DOE Patents [OSTI]

    Kulsrud, R.M.; Furth, H.P.; Valeo, E.J.; Goldhaber, M.

    1983-05-09

    This invention relates to a method of controlling the reaction rates in a nuclear fusion reactor; and more particularly, to the use of polarized nuclear fuel.

  17. Photovoltaic Degradation Rates -- An Analytical Review

    SciTech Connect (OSTI)

    Jordan, D. C.; Kurtz, S. R.

    2012-06-01

    As photovoltaic penetration of the power grid increases, accurate predictions of return on investment require accurate prediction of decreased power output over time. Degradation rates must be known in order to predict power delivery. This article reviews degradation rates of flat-plate terrestrial modules and systems reported in published literature from field testing throughout the last 40 years. Nearly 2000 degradation rates, measured on individual modules or entire systems, have been assembled from the literature, showing a median value of 0.5%/year. The review consists of three parts: a brief historical outline, an analytical summary of degradation rates, and a detailed bibliography partitioned by technology.

  18. BPA issues final decision on oversupply rate

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

    is consistent with our multiple statutory responsibilities, is rooted in the basic principles of cost causation and fairness that underlie BPA's rate directives, and...

  19. Introducing the Attachments Energy Ratings Council

    Broader source: Energy.gov [DOE]

    In collaboration with the U.S. Department of Energy (DOE), the Window Covering Manufacturers Association (WCMA) has launched the Attachments Energy Ratings Council (AERC).

  20. Floating Rate Agreement | Department of Energy

    Office of Environmental Management (EM)

    & Publications Fixed Rate Agreement Federal Loan Guarantees for Projects that Manufacture Commercial Technology Renewable Energy Systems and Components: August 10, 2010...

  1. BPA proposes rate increase to bolster

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

    proposed a 9.6 percent average wholesale power rate increase to compensate for reduced revenue expectations from surplus power sales and to continue funding needed investments in...

  2. Dose factor entry and display tool for BNCT radiotherapy

    DOE Patents [OSTI]

    Wessol, Daniel E. (Bozeman, MT); Wheeler, Floyd J. (Idaho Falls, ID); Cook, Jeremy L. (Greeley, CO)

    1999-01-01

    A system for use in Boron Neutron Capture Therapy (BNCT) radiotherapy planning where a biological distribution is calculated using a combination of conversion factors and a previously calculated physical distribution. Conversion factors are presented in a graphical spreadsheet so that a planner can easily view and modify the conversion factors. For radiotherapy in multi-component modalities, such as Fast-Neutron and BNCT, it is necessary to combine each conversion factor component to form an effective dose which is used in radiotherapy planning and evaluation. The Dose Factor Entry and Display System is designed to facilitate planner entry of appropriate conversion factors in a straightforward manner for each component. The effective isodose is then immediately computed and displayed over the appropriate background (e.g. digitized image).

  3. Population exposure dose reconstruction for the Urals Region

    SciTech Connect (OSTI)

    Degteva, M.O.; Kozheurov, V.P.; Vorobiova, M.I.; Burmistrov, D.S.; Khokhryakov, V.V.; Suslova, K.G.; Anspaugh, L.R.; Napier, B.A.; Bouville, A.

    1996-06-01

    This presentation describes the first preliminary results of an ongoing joint Russian-US pilot feasibility study. Many people participated in workshops to determine what Russian and United States scientists could do together in the area of dose reconstruction in the Urals population. Most of the results presented here came from a joint work shop in St. Petersburg, Russia (11-13 July 1995). The Russians at the workshop represented the Urals Research Center for Radiation Medicine (URCRM), the Mayak Industrial Association, and Branch One of the Moscow Biophysics Institute. The US Collaborators were Dr. Anspaugh of LLNL, Dr. Nippier of PNL, and Dr. Bouville of the National Cancer Institute. The objective of the first year of collaboration was to look at the source term and levels of radiation contamination, the historical data available, and the results of previous work carried out by Russian scientists, and to determine a conceptual model for dose reconstruction.

  4. Axillary lymph node dose with tangential breast irradiation

    SciTech Connect (OSTI)

    Reed, Daniel R. . E-mail: drreed@u.washington.edu; Lindsley, Skyler Karen; Mann, Gary N.; Austin-Seymour, Mary; Korssjoen, Tammy; Anderson, Benjamin O.; Moe, Roger

    2005-02-01

    Purpose: The advent of sentinel lymph node mapping and biopsy in the staging of breast cancer has resulted in a significant decrease in the extent of axillary nodal surgery. As the extent of axillary surgery decreases, the radiation dose and distribution within the axilla becomes increasingly important for current therapy planning and future analysis of results. This analysis examined the radiation dose distribution delivered to the anatomically defined axillary level I and II lymph node volume and surgically placed axillary clips with conventional tangential breast fields and CT-based three-dimensional (3D) planning. Methods and materials: Fifty consecutive patients with early-stage breast cancer undergoing breast conservation therapy were evaluated. All patients underwent 3D CT-based planning with conventional breast tangential fields designed to encompass the entire breast parenchyma. Using CT-based 3D planning, the dose distribution of the standard tangential breast irradiation fields was examined in relationship to the axillary level I and II lymph node volumes. Axillary level I and II lymph node anatomic volumes were defined by CT and surgical clips placed during complete level I-II lymph node dissection. Axillary level I-II lymph node volume doses were examined on the basis of the prescribed breast radiation dose and 3D dose distribution. Results: All defined breast volumes received {>=}95% of the prescribed dose. By contrast, the 95% isodose line encompassed only an average of 55% (range, 23-87%) of the axillary level I-II lymph node anatomic volume. No patient had complete coverage of the axillary level I-II lymph node region by the 95% isodose line. The mean anatomic axillary level I-II volume was 146.3 cm{sup 3} (range, 83.1-313.0 cm{sup 3}). The mean anatomic axillary level I-II volume encompassed by the 95% isodose line was 84.9 cm{sup 3} (range, 25.1-219.0 cm{sup 3}). The mean 95% isodose coverage of the surgical clip volume was 80%, and the median value was 81% (range, 58-98%). The mean volume deficit between the axillary level I-II volume and the surgical clip volume was 41.7 cm{sup 3} (median, 30.0 cc). Conclusion: In this study, standard tangential breast radiation fields failed to deliver a therapeutic dose adequately to the axillary level I-II lymph node anatomic volume. No patient received complete coverage of the axillary level I-II lymph node volume. Surgically placed axillary clips also failed to delineate the level I-II axilla adequately. Definitive irradiation of the level I and II axillary lymph node region requires significant modification of standard tangential fields, best accomplished with 3D treatment planning, with specific targeting of anatomically defined axillary lymph node volumes as described, in addition to the breast parenchymal volumes.

  5. Fast optimization and dose calculation in scanned ion beam therapy

    SciTech Connect (OSTI)

    Hild, S.; Graeff, C.; Trautmann, J.; Kraemer, M.; Zink, K.; Durante, M.; Bert, C.

    2014-07-15

    Purpose: Particle therapy (PT) has advantages over photon irradiation on static tumors. An increased biological effectiveness and active target conformal dose shaping are strong arguments for PT. However, the sensitivity to changes of internal geometry complicates the use of PT for moving organs. In case of interfractionally moving objects adaptive radiotherapy (ART) concepts known from intensity modulated radiotherapy (IMRT) can be adopted for PT treatments. One ART strategy is to optimize a new treatment plan based on daily image data directly before a radiation fraction is delivered [treatment replanning (TRP)]. Optimizing treatment plans for PT using a scanned beam is a time consuming problem especially for particles other than protons where the biological effective dose has to be calculated. For the purpose of TRP, fast optimization and fast dose calculation have been implemented into the GSI in-house treatment planning system (TPS) TRiP98. Methods: This work reports about the outcome of a code analysis that resulted in optimization of the calculation processes as well as implementation of routines supporting parallel execution of the code. To benchmark the new features, the calculation time for therapy treatment planning has been studied. Results: Compared to the original version of the TPS, calculation times for treatment planning (optimization and dose calculation) have been improved by a factor of 10 with code optimization. The parallelization of the TPS resulted in a speedup factor of 12 and 5.5 for the original version and the code optimized version, respectively. Hence the total speedup of the new implementation of the authors' TPS yielded speedup factors up to 55. Conclusions: The improved TPS is capable of completing treatment planning for ion beam therapy of a prostate irradiation considering organs at risk in this has been overseen in the review process. Also see below 6 min.

  6. Low Dose Irradiation Facility | Savannah River Ecology Laboratory

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

    Low Dose Irradiation Facility (LoDIF) The LoDIF is a unique facility designed to evaluate the impact of chronic, low-level radiation exposure on aquatic organisms. The facility is an array of 40 outdoor mesocosms equipped with cesium-137 irradiation sources or unexposed controls. Irradiation sources provide three biologically relevant levels of exposure: 2, 20, and 200 mGy/d mean exposure. Mesocosms are arranged into eight blocks, with five mesocosms per block (three levels of irradiation and

  7. High Dose Neutron Irradiation Performance of Dielectric Mirrors

    SciTech Connect (OSTI)

    Nimishakavi, Anantha Phani Kiran Kumar; Leonard, Keith J; Jellison Jr, Gerald Earle; Snead, Lance Lewis

    2015-01-01

    The study presents the high-dose behavior of dielectric mirrors specifically engineered for radiation-tolerance: alternating layers of Al2O3/SiO2 and HfO2/SiO2 were grown on sapphire substrates and exposed to neutron doses of 1 and 4 dpa at 458 10K in the High Flux Isotope Reactor (HFIR). In comparison to previously reported results, these higher doses of 1 and 4 dpa results in a drastic drop in optical reflectance, caused by a failure of the multilayer coating. HfO2/SiO2 mirrors failed completely when exposed to 1 dpa, whereas the reflectance of Al2O3/SiO2 mirrors reduced to 44%, eventually failing at 4 dpa. Transmission electron microscopy (TEM) observation of the Al2O3/SiO2 specimens showed SiO2 layer defects which increases size with irradiation dose. The typical size of each defect was 8 nm in 1 dpa and 42 nm in 4 dpa specimens. Buckling type delamination of the interface between the substrate and first layer was typically observed in both 1 and 4 dpa HfO2/SiO2 specimens. Composition changes across the layers were measured in high resolution scanning-TEM mode using energy dispersive spectroscopy. A significant interdiffusion between the film layers was observed in Al2O3/SiO2 mirror, though less evident in HfO2/SiO2 system. The ultimate goal of this work is the provide insight into the radiation-induced failure mechanisms of these mirrors.

  8. Heterogeneity-corrected vs -uncorrected critical structure maximum point doses in breast balloon brachytherapy

    SciTech Connect (OSTI)

    Kim, Leonard; Narra, Venkat; Yue, Ning

    2013-07-01

    Recent studies have reported potentially clinically meaningful dose differences when heterogeneity correction is used in breast balloon brachytherapy. In this study, we report on the relationship between heterogeneity-corrected and -uncorrected doses for 2 commonly used plan evaluation metrics: maximum point dose to skin surface and maximum point dose to ribs. Maximum point doses to skin surface and ribs were calculated using TG-43 and Varian Acuros for 20 patients treated with breast balloon brachytherapy. The results were plotted against each other and fit with a zero-intercept line. Max skin dose (Acuros) = max skin dose (TG-43) ? 0.930 (R{sup 2} = 0.995). The average magnitude of difference from this relationship was 1.1% (max 2.8%). Max rib dose (Acuros) = max rib dose (TG-43) ? 0.955 (R{sup 2} = 0.9995). The average magnitude of difference from this relationship was 0.7% (max 1.6%). Heterogeneity-corrected maximum point doses to the skin surface and ribs were proportional to TG-43-calculated doses. The average deviation from proportionality was 1%. The proportional relationship suggests that a different metric other than maximum point dose may be needed to obtain a clinical advantage from heterogeneity correction. Alternatively, if maximum point dose continues to be used in recommended limits while incorporating heterogeneity correction, institutions without this capability may be able to accurately estimate these doses by use of a scaling factor.

  9. Radiological assessment. A textbook on environmental dose analysis

    SciTech Connect (OSTI)

    Till, J.E.; Meyer, H.R.

    1983-09-01

    Radiological assessment is the quantitative process of estimating the consequences to humans resulting from the release of radionuclides to the biosphere. It is a multidisciplinary subject requiring the expertise of a number of individuals in order to predict source terms, describe environmental transport, calculate internal and external dose, and extrapolate dose to health effects. Up to this time there has been available no comprehensive book describing, on a uniform and comprehensive level, the techniques and models used in radiological assessment. Radiological Assessment is based on material presented at the 1980 Health Physics Society Summer School held in Seattle, Washington. The material has been expanded and edited to make it comprehensive in scope and useful as a text. Topics covered include (1) source terms for nuclear facilities and Medical and Industrial sites; (2) transport of radionuclides in the atmosphere; (3) transport of radionuclides in surface waters; (4) transport of radionuclides in groundwater; (5) terrestrial and aquatic food chain pathways; (6) reference man; a system for internal dose calculations; (7) internal dosimetry; (8) external dosimetry; (9) models for special-case radionuclides; (10) calculation of health effects in irradiated populations; (11) evaluation of uncertainties in environmental radiological assessment models; (12) regulatory standards for environmental releases of radionuclides; (13) development of computer codes for radiological assessment; and (14) assessment of accidental releases of radionuclides.

  10. Stereotactic, Single-Dose Irradiation of Lung Tumors: A Comparison of Absolute Dose and Dose Distribution Between Pencil Beam and Monte Carlo Algorithms Based on Actual Patient CT Scans

    SciTech Connect (OSTI)

    Chen Huixiao; Lohr, Frank; Fritz, Peter; Wenz, Frederik; Dobler, Barbara; Lorenz, Friedlieb; Muehlnickel, Werner

    2010-11-01

    Purpose: Dose calculation based on pencil beam (PB) algorithms has its shortcomings predicting dose in tissue heterogeneities. The aim of this study was to compare dose distributions of clinically applied non-intensity-modulated radiotherapy 15-MV plans for stereotactic body radiotherapy between voxel Monte Carlo (XVMC) calculation and PB calculation for lung lesions. Methods and Materials: To validate XVMC, one treatment plan was verified in an inhomogeneous thorax phantom with EDR2 film (Eastman Kodak, Rochester, NY). Both measured and calculated (PB and XVMC) dose distributions were compared regarding profiles and isodoses. Then, 35 lung plans originally created for clinical treatment by PB calculation with the Eclipse planning system (Varian Medical Systems, Palo Alto, CA) were recalculated by XVMC (investigational implementation in PrecisePLAN [Elekta AB, Stockholm, Sweden]). Clinically relevant dose-volume parameters for target and lung tissue were compared and analyzed statistically. Results: The XVMC calculation agreed well with film measurements (<1% difference in lateral profile), whereas the deviation between PB calculation and film measurements was up to +15%. On analysis of 35 clinical cases, the mean dose, minimal dose and coverage dose value for 95% volume of gross tumor volume were 1.14 {+-} 1.72 Gy, 1.68 {+-} 1.47 Gy, and 1.24 {+-} 1.04 Gy lower by XVMC compared with PB, respectively (prescription dose, 30 Gy). The volume covered by the 9 Gy isodose of lung was 2.73% {+-} 3.12% higher when calculated by XVMC compared with PB. The largest differences were observed for small lesions circumferentially encompassed by lung tissue. Conclusions: Pencil beam dose calculation overestimates dose to the tumor and underestimates lung volumes exposed to a given dose consistently for 15-MV photons. The degree of difference between XVMC and PB is tumor size and location dependent. Therefore XVMC calculation is helpful to further optimize treatment planning.

  11. Method of controlling fusion reaction rates

    DOE Patents [OSTI]

    Kulsrud, Russell M. (Princeton, NJ); Furth, Harold P. (Princeton, NJ); Valeo, Ernest J. (Princeton Junction, NJ); Goldhaber, Maurice (Bayport, NY)

    1988-01-01

    A method of controlling the reaction rates of the fuel atoms in a fusion reactor comprises the step of polarizing the nuclei of the fuel atoms in a particular direction relative to the plasma confining magnetic field. Fusion reaction rates can be increased or decreased, and the direction of emission of the reaction products can be controlled, depending on the choice of polarization direction.

  12. Radon Dose Determination for Cave Guides in Czech Republic

    SciTech Connect (OSTI)

    Thinova, Lenka; Rovenska, Katerina

    2008-08-07

    According to recommended approach there are six (from total of twelve) open-to-public caves in Czech Republic, reaching near to an effective lung-dose of 6mSv/year. A conservative approach for estimating the potential effective lung-dose in caves (or underground) is based on two season's measurements, using solid state alpha track detector (Kodak in plastic diffusion chamber). The obtained dataset is converted into an annual effective dose, in agreement with the ICRP65 recommendation, using the 'cave factor' 1.5. The value of 'cave factor' which depends on the spectrum of aerosol particles, or on the proportional representation of the unattached/attached ratio (6.5 : 93.5 for residential places, 13.6 : 86.4 for caves due to lower concentration of free aerosols) and on the equilibrium factor. Thus conversion factor is 1.5 times higher in comparison with ICRP 65. Is this correct? Because a more precisely determined dose value would have a significant impact on radon remedies, or on restricting the time workers stay underground, a series of measurement was initiated in 2003 with the aim to specify input data, computation and errors in effective dose assessment in each one of the evaluated caves separately. The enhancement of personal dosimetry for underground work places includes a study of the given questions, from the following points of view in each cave: continual radon measurement; regular measurements of radon and its daughters to estimate the equilibrium factor and the presence of free {sup 218}Po; regular indoor air flow measurements to study the location of the radon supply and its transfer among individual areas of the cave; natural radioactive element content evaluation in subsoil and in water inside/outside, a study of the radon sources in the cave; determination of the free fraction from continual unattached and attached fraction measurement (grid and filter); thoron measurement. Air flow measurements provide very interesting information about the origin of 'radon pockets' with very high radon concentration, and enable study of the location of the radon supply and its transfer among individual areas of the cave. Most of the results show the equilibrium factor around F = 0.2-0.7 and the unattached fraction around 2%-30%. One of the most important question remains: how accurately was the unattached fraction measured? Part of this project was to verify the influence of etched track detector position in the cave.

  13. Revenue-stability-target rate making

    SciTech Connect (OSTI)

    Chernick, P.L.

    1983-02-17

    The commonly used rate-making approaches necessarily base themselves on assumptions, vital to their success, about future levels of utility aservice sales. But since sales are a function of random variables beyond the control of the utility as well as actions by the utility itself, the resulting rates fail to protect the utility's revenue stream and its realized rate of return. This article proposes an alternative approach which would decouple utility revenues from sales, thus stabilizing revenue streams with respect to sales fluctuations and rate design changes. Among the benefits would be a lower cost of capital for the utility, as well as decreased utility resistance to conservation by consumers and to efficient rate design.

  14. Measuring Degradation Rates Without Irradiance Data

    SciTech Connect (OSTI)

    Pulver, S.; Cormode, D.; Cronin, A.; Jordan, D.; Kurtz, S.; Smith, R.

    2011-02-01

    A method to report PV system degradation rates without using irradiance data is demonstrated. First, a set of relative degradation rates are determined by comparing daily AC final yields from a group of PV systems relative to the average final yield of all the PV systems. Then, the difference between relative and absolute degradation rates is found from a statistical analysis. This approach is verified by comparing to methods that utilize irradiance data. This approach is significant because PV systems are often deployed without irradiance sensors, so the analysis method described here may enable measurements of degradation using data that were previously thought to be unsuitable for degradation studies.

  15. Considerations for How to Rate CPV

    SciTech Connect (OSTI)

    Kurtz, S.; Miller, M.; Marion, B.; Emery, K.; McConnell, R.; Surendran, S.; Kimber, A.

    2011-02-01

    The concentrator photovoltaic (CPV) industry is introducing multiple products into the marketplace, but, as yet, the; community has not embraced a unified method for assessing a nameplate rating. The choices of whether to use 850,; 900, or 1000 W/m2 for the direct-normal irradiance and whether to link the rating to ambient or cell temperature will; affect how CPV modules are rated and compared with other technologies. This paper explores the qualitative and; quantitative ramifications of these choices using data from two multi-junction CPV modules and two flat-plate; modules.

  16. A New Approach in Urea Dosing to Improve Performance and Durability...

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

    Approach in Urea Dosing to Improve Performance and Durability of SCR Systems for the Use in Off-Road Applications to Fulfill Tier 4 Final A New Approach in Urea Dosing to Improve...

  17. Property:OpenEI/UtilityRate/DemandRateStructure/Tier2Adjustment...

    Open Energy Info (EERE)

    search This is a property of type Number. Retrieved from "http:en.openei.orgwindex.php?titleProperty:OpenEIUtilityRateDemandRateStructureTier2Adjustment&oldid539746...

  18. Property:OpenEI/UtilityRate/DemandRateStructure/Tier5Max | Open...

    Open Energy Info (EERE)

    navigation, search This is a property of type Number. Retrieved from "http:en.openei.orgwindex.php?titleProperty:OpenEIUtilityRateDemandRateStructureTier5Max&oldid539754...

  19. Property:OpenEI/UtilityRate/EnergyRateStructure/Tier1Max | Open...

    Open Energy Info (EERE)

    navigation, search This is a property of type Number. Retrieved from "http:en.openei.orgwindex.php?titleProperty:OpenEIUtilityRateEnergyRateStructureTier1Max&oldid539766...

  20. Property:OpenEI/UtilityRate/EnergyRateStructure/Tier1Sell | Open...

    Open Energy Info (EERE)

    navigation, search This is a property of type Number. Retrieved from "http:en.openei.orgwindex.php?titleProperty:OpenEIUtilityRateEnergyRateStructureTier1Sell&oldid539770...

  1. Property:OpenEI/UtilityRate/DemandRateStructure/Tier6Adjustment...

    Open Energy Info (EERE)

    search This is a property of type Number. Retrieved from "http:en.openei.orgwindex.php?titleProperty:OpenEIUtilityRateDemandRateStructureTier6Adjustment&oldid539759...

  2. Property:OpenEI/UtilityRate/DemandRateStructure/Tier4Max | Open...

    Open Energy Info (EERE)

    navigation, search This is a property of type Number. Retrieved from "http:en.openei.orgwindex.php?titleProperty:OpenEIUtilityRateDemandRateStructureTier4Max&oldid539751...

  3. Getting Rate Information from the utility_rates api | OpenEI...

    Open Energy Info (EERE)

    Getting Rate Information from the utilityrates api Home > Groups > Utility Rate Hello, I am trying to use the API to generate information similar to what you can see here: http:...

  4. Property:OpenEI/UtilityRate/EnergyRateStructure/Tier4Sell | Open...

    Open Energy Info (EERE)

    Property Edit with form History Facebook icon Twitter icon Property:OpenEIUtilityRateEnergyRateStructureTier4Sell Jump to: navigation, search This is a property of type...

  5. Property:OpenEI/UtilityRate/EnergyRateStructure/Tier3Adjustment...

    Open Energy Info (EERE)

    Property Edit with form History Facebook icon Twitter icon Property:OpenEIUtilityRateEnergyRateStructureTier3Adjustment Jump to: navigation, search This is a property of type...

  6. Property:OpenEI/UtilityRate/EnergyRateStructure/Tier5Sell | Open...

    Open Energy Info (EERE)

    Property Edit with form History Facebook icon Twitter icon Property:OpenEIUtilityRateEnergyRateStructureTier5Sell Jump to: navigation, search This is a property of type...

  7. Property:OpenEI/UtilityRate/EnergyRateStructure/Period | Open...

    Open Energy Info (EERE)

    This is a property of type Number. The allowed values for this property are: 1 2 3 4 5 6 7 8 9 Pages using the property "OpenEIUtilityRateEnergyRateStructurePeriod" Showing...

  8. Low Dose IR Creates an Oncogenic Microenvironment by Inducing Premature

    SciTech Connect (OSTI)

    Yuan, Zhi-Min

    2013-04-28

    Introduction Much of the work addressing ionizing radiation-induced cellular response has been carried out mainly with the traditional cell culture technique involving only one cell type, how cellular response to IR is influenced by the tissue microenvironment remains elusive. By use of a three-dimensional (3D) co-culture system to model critical interactions of different cell types with their neighbors and with their environment, we recently showed that low-dose IR-induced extracellular signaling via the tissue environment affects profoundly cellular responses. This proposal aims at determining the response of mammary epithelial cells in a tissue-like setting.

  9. Annual report shows potential INL radiation doses well below safe

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

    regulatory limits Annual report shows potential INL radiation doses well below safe regulatory limits July 21, 2010 Media contact: Tim Jackson (208) 526-8484 Idaho Falls, ID � The U.S. Department of Energy�s Idaho Operations Office reported this month that radiation from the site falls well below limits established by the U.S. Environmental Protection Agency. The report�s conclusions are supported by direct environmental monitoring data routinely taken during the year, and show that

  10. Hanford Environmental Dose Reconstruction Project, Quarterly report, September--November 1993

    SciTech Connect (OSTI)

    Cannon, S.D.; Finch, S.M.

    1993-12-31

    The objective of the Hanford Environmental Dose Reconstruction (HEDR) Project is to estimate the radiation doses that individuals and populations could have received from nuclear operations at Hanford since 1944. The project is divided into the following technical tasks. These tasks correspond to the path radionuclides followed from release to impact on humans (dose estimates); Source Terms, Environmental Transport, Environmental Monitoring Data, Demography, Food Consumption, and Agriculture, and Environmental Pathways and Dose Estimates.

  11. Hanford Environmental Dose Reconstruction Project. Quarterly report, December 1993--February 1994

    SciTech Connect (OSTI)

    Cannon, S.D.

    1994-04-01

    The objective of the Hanford Environmental Dose Reconstruction (HEDR) Project is to estimate the radiation doses that individuals and populations could have received from nuclear operations at Hanford since 1944. The project is divided into the following technical tasks. These tasks correspond to the path radio-nuclides followed from release to impact on humans(dose estimates): source terms; environmental transport; environmental monitoring data; demography, food consumption, agriculture; environmental pathways; and dose estimates.

  12. SU-E-CAMPUS-T-03: Four-Dimensional Dose Distribution Measurement Using

    Office of Scientific and Technical Information (OSTI)

    Plastic Scintillator (Journal Article) | SciTech Connect SU-E-CAMPUS-T-03: Four-Dimensional Dose Distribution Measurement Using Plastic Scintillator Citation Details In-Document Search Title: SU-E-CAMPUS-T-03: Four-Dimensional Dose Distribution Measurement Using Plastic Scintillator Purpose: To develop the detector for the four-dimensional dose distribution measurement. Methods: We made the prototype detector for four-dimensional dose distribution measurement using a cylindrical plastic

  13. PSNC Energy (Gas)- Green Building Rate Discount

    Broader source: Energy.gov [DOE]

    This discounted rate is available to commercial customers whose building meets the U.S. Green Building Council’s Leadership in Energy and Environmental Design (LEED) certification or equivalent. To...

  14. Minority Utility Rate Design Assessment Model

    Energy Science and Technology Software Center (OSTI)

    2003-01-20

    Econometric model simulates consumer demand response to various user-supplied, two-part tariff electricity rate designs and assesses their economic welfare impact on black, hispanic, poor and majority households.

  15. Dynamic Line Rating: Research and Policy Evaluation

    SciTech Connect (OSTI)

    Jake P. Gentle; Kurt S. Myers; Michael R. West

    2014-07-01

    Dynamic Line Rating (DLR) is a smart grid technology that allows the rating of electrical conductors to be increased based on local weather conditions. Overhead lines are conventionally given a conservative rating based on worst case scenarios. We demonstrate that observing the conditions in real time leads to additional capacity and safer operation. This paper provides a report of a pioneering scheme in the United States of America in which DLR has been applied. Thereby, we demonstrate that observing the local weather conditions in real time leads to additional capacity and safer operation. Secondly, we discuss limitations involved. In doing so, we arrive at novel insights which will inform and improve future DLR projects. Third, we provide a policy background and discussion to clarify the technology’s potential and identifies barriers to the imminent adoption of dynamic line rating systems. We provide suggestions for regulatory bodies about possible improvements in policy to encourage adoption of this beneficial technology.

  16. BPA Power Rates (pbl/main)

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

    ASC Methodology Adjustments (2007-2009) Adjustments (2002-2006) Previous Rate Cases Financial Choices (2003-06) Power Function Review (PFR) Firstgov BPA Fuel Mix 2012 2013 2014...

  17. Utility Rate | OpenEI Community

    Open Energy Info (EERE)

    > Posts by term > Utility Rate Content Group Activity By term Q & A Feeds Term: Global Atlas Type Term Title Author Replies Last Post sort icon Blog entry Global Atlas IRENA...

  18. Utility Rates | OpenEI Community

    Open Energy Info (EERE)

    Rates I'm considering removing the "Show Preview" button, since it does not work (javascript validation issue that could be fixed), and it doesn't make sense. The reason to...

  19. Uncertainty Analysis for Photovoltaic Degradation Rates (Poster)

    SciTech Connect (OSTI)

    Jordan, D.; Kurtz, S.; Hansen, C.

    2014-04-01

    Dependable and predictable energy production is the key to the long-term success of the PV industry. PV systems show over the lifetime of their exposure a gradual decline that depends on many different factors such as module technology, module type, mounting configuration, climate etc. When degradation rates are determined from continuous data the statistical uncertainty is easily calculated from the regression coefficients. However, total uncertainty that includes measurement uncertainty and instrumentation drift is far more difficult to determine. A Monte Carlo simulation approach was chosen to investigate a comprehensive uncertainty analysis. The most important effect for degradation rates is to avoid instrumentation that changes over time in the field. For instance, a drifting irradiance sensor, which can be achieved through regular calibration, can lead to a substantially erroneous degradation rates. However, the accuracy of the irradiance sensor has negligible impact on degradation rate uncertainty emphasizing that precision (relative accuracy) is more important than absolute accuracy.

  20. Contract and Tiered Rate Methodology Overview

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

    historical demand to provide incentive to lower their peak by providing a marginal price signal on an incremental component of demand. The CDQs are calculated outside of the rate...

  1. Utility Rate | OpenEI Community

    Open Energy Info (EERE)

    Utility Rate Home > Groups Content Group Activity By term Q & A Feeds Share your own status updates, and follow the updates & activities of others by creating your own account. Or,...

  2. Revenue instability induced by conservation rates

    SciTech Connect (OSTI)

    Chesnutt, T.W.; McSpadden, C.; Christianson, J.

    1996-01-01

    The shift toward conservation rate structures, although they may provide better incentives to use scarce water wisely, changes who pays what and can increase the variability of future revenue streams to the water agency. Though the definition of the correct rate structure varies by community, the managerial strategies necessary to cope with the uncertainty brought about by conservation rate structures apply universally. Revenue instability directly increases water supplier`s borrowing costs and adds indirect costs in the form of more complicated planning to provide for a reliable future water supply. This article describes an empirical study using data from two water agencies that have adopted conservation rate structures. The article proposes ways quantitative tools may be used to (1) measure and cope with added uncertainty and (2) make explicit the magnitude of trade-offs between revenue stability, equity, and the provision of incentives for efficient use of water resources.

  3. Calibration and Rating of Photovoltaics: Preprint

    SciTech Connect (OSTI)

    Emery, K.

    2012-06-01

    Rating the performance of photovoltaic (PV) modules is critical to determining the cost per watt, and efficiency is useful to assess the relative progress among PV concepts. Procedures for determining the efficiency for PV technologies from 1-sun to low concentration to high concentration are discussed. We also discuss the state of the art in primary and secondary calibration of PV reference cells used by calibration laboratories around the world. Finally, we consider challenges to rating PV technologies and areas for improvement.

  4. ARM - Lesson Plans: Rate of Coral Growth

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

    Rate of Coral Growth Outreach Home Room News Publications Traditional Knowledge Kiosks Barrow, Alaska Tropical Western Pacific Site Tours Contacts Students Study Hall About ARM Global Warming FAQ Just for Fun Meet our Friends Cool Sites Teachers Teachers' Toolbox Lesson Plans Lesson Plans: Rate of Coral Growth Objective The objective is to understand the fact that the growth of coral depends on water depth and the effect of sea level changes on corals. Materials Each student or group of students

  5. DWPF Macrobatch 2 Melt Rate Tests

    SciTech Connect (OSTI)

    Stone, M.E.

    2001-01-03

    The Defense Waste Processing Facility (DWPF) canister production rate must be increased to meet canister production goals. Although a number of factors exist that could potentially increase melt rate, this study focused on two: (1) changes in frit composition and (2) changes to the feed preparation process to alter the redox of the melter feed. These two factors were investigated for Macrobatch 2 (sludge batch 1B) utilizing crucible studies and a specially designed ''melt rate'' furnace. Other potential factors that could increase melt rate include: mechanical mixing via stirring or the use of bubblers, changing the power skewing to redistribute the power input to the melter, and elimination of heat loss (e.g. air in leakage). The melt rate testing in FY00 demonstrated that melt rate can be improved by adding a different frit or producing a much more reducing glass by the addition of sugar as a reductant. The frit that melted the fastest in the melt rate testing was Frit 165. A paper stud y was performed using the Product Composition Control System (PCCS) to determine the impact on predicted glass viscosity, liquidus, durability, and operating window if the frit was changed from Frit 200 to Frit 165. PCCS indicated that the window was very similar for both frits. In addition, the predicted viscosity of the frit 165 glass was 46 poise versus 84 poise for the Frit 200 glass. As a result, a change from Frit 200 to Frit 165 is expected to increase the melt rate in DWPF without decreasing waste loading.

  6. Decision Regret in Men Undergoing Dose-Escalated Radiation Therapy for Prostate Cancer

    SciTech Connect (OSTI)

    Steer, Anna N.; Aherne, Noel J.; Gorzynska, Karen; Hoffman, Matthew; Last, Andrew; Hill, Jacques; Shakespeare, Thomas P.; Rural Clinical School Faculty of Medicine, University of New South Wales, Coffs Harbour

    2013-07-15

    Purpose: Decision regret (DR) is a negative emotion associated with medical treatment decisions, and it is an important patient-centered outcome after therapy for localized prostate cancer. DR has been found to occur in up to 53% of patients treated for localized prostate cancer, and it may vary depending on treatment modality. DR after modern dose-escalated radiation therapy (DE-RT) has not been investigated previously, to our knowledge. Our primary aim was to evaluate DR in a cohort of patients treated with DE-RT. Methods and Materials: We surveyed 257 consecutive patients with localized prostate cancer who had previously received DE-RT, by means of a validated questionnaire. Results: There were 220 responses (85.6% response rate). Image-guided intensity modulated radiation therapy was given in 85.0% of patients and 3-dimensional conformal radiation therapy in 15.0%. Doses received included 73.8 Gy (34.5% patients), 74 Gy (53.6%), and 76 Gy (10.9%). Neoadjuvant androgen deprivation (AD) was given in 51.8% of patients and both neoadjuvant and adjuvant AD in 34.5%. The median follow-up time was 23 months (range, 12-67 months). In all, 3.8% of patients expressed DR for their choice of treatment. When asked whether they would choose DE-RT or AD again, only 0.5% probably or definitely would not choose DE-RT again, compared with 8.4% for AD (P<.01). Conclusion: Few patients treated with modern DE-RT express DR, with regret appearing to be lower than in previously published reports of patients treated with radical prostatectomy or older radiation therapy techniques. Patients experienced more regret with the AD component of treatment than with the radiation therapy component, with implications for informed consent. Further research should investigate regret associated with individual components of modern therapy, including AD, radiation therapy and surgery.

  7. Realization rates of the National Energy Audit

    SciTech Connect (OSTI)

    Berry, L.G.; Gettings, M.B.

    1998-11-01

    Engineering estimates of savings resulting from installation of energy conservation measures in homes are often greater than the savings actually realized. A brief review of prior studies of realization rates prefaces this study of rates from an engineering audit tool, NEAT, (developed for the Department of Energy`s Low-Income Weatherization Assistance Program) used in a New York state utility`s low-income program. Estimates of metered and predicted savings are compared for 49 homes taken from a data base of homes that participated in the first year of the utility`s program. Average realization rates ranging from 57% to 69% result, depending on the data quality. Detailed examinations of two houses using an alternate engineering method, the DOE-2 computer program (considered an industry standard), seem to indicate that the low realization rates mainly result from factors other than inaccuracies in the audit`s internal algorithms. Causes of the low realization rates are examined, showing that the strongest single factor linked to the low rates in this study is the use of secondary heating fuels that supplement the primary heating fuel. This study, like the other similar studies, concludes that engineering estimates are valuable tools in determining ranked lists of cost-effective weatherization measures, but may not be accurate substitutes for measured results in evaluating program performance.

  8. Dose-to-water conversion for the backscatter-shielded EPID: A frame-based method to correct for EPID energy response to MLC transmitted radiation

    SciTech Connect (OSTI)

    Zwan, Benjamin J. OConnor, Daryl J.; King, Brian W.; Greer, Peter B.

    2014-08-15

    Purpose: To develop a frame-by-frame correction for the energy response of amorphous silicon electronic portal imaging devices (a-Si EPIDs) to radiation that has transmitted through the multileaf collimator (MLC) and to integrate this correction into the backscatter shielded EPID (BSS-EPID) dose-to-water conversion model. Methods: Individual EPID frames were acquired using a Varian frame grabber and iTools acquisition software then processed using in-house software developed inMATLAB. For each EPID image frame, the region below the MLC leaves was identified and all pixels in this region were multiplied by a factor of 1.3 to correct for the under-response of the imager to MLC transmitted radiation. The corrected frames were then summed to form a corrected integrated EPID image. This correction was implemented as an initial step in the BSS-EPID dose-to-water conversion model which was then used to compute dose planes in a water phantom for 35 IMRT fields. The calculated dose planes, with and without the proposed MLC transmission correction, were compared to measurements in solid water using a two-dimensional diode array. Results: It was observed that the integration of the MLC transmission correction into the BSS-EPID dose model improved agreement between modeled and measured dose planes. In particular, the MLC correction produced higher pass rates for almost all Head and Neck fields tested, yielding an average pass rate of 99.8% for 2%/2 mm criteria. A two-sample independentt-test and fisher F-test were used to show that the MLC transmission correction resulted in a statistically significant reduction in the mean and the standard deviation of the gamma values, respectively, to give a more accurate and consistent dose-to-water conversion. Conclusions: The frame-by-frame MLC transmission response correction was shown to improve the accuracy and reduce the variability of the BSS-EPID dose-to-water conversion model. The correction may be applied as a preprocessing step in any pretreatment portal dosimetry calculation and has been shown to be beneficial for highly modulated IMRT fields.

  9. Dose-Effect Relationships for Femoral Fractures After Multimodality Limb-Sparing Therapy of Soft-Tissue Sarcomas of the Proximal Lower Extremity

    SciTech Connect (OSTI)

    Pak, Daniel; Vineberg, Karen A. [Department of Radiation Oncology, University of Michigan, Ann Arbor, MI (United States); Griffith, Kent A. [Biostatistics Unit, Comprehensive Cancer Center, University of Michigan, Ann Arbor, MI (United States); Sabolch, Aaron [Department of Radiation Oncology, University of Michigan, Ann Arbor, MI (United States); Chugh, Rashmi [Department of Internal Medicine, Division of Hematology/Oncology, University of Michigan, Ann Arbor, MI (United States); Ben-Josef, Edgar [Department of Radiation Oncology, University of Michigan, Ann Arbor, MI (United States); Biermann, Janet Sybil [Department of Orthopedic Surgery, University of Michigan, Ann Arbor, MI (United States); Feng, Mary, E-mail: maryfeng@umich.edu [Department of Radiation Oncology, University of Michigan, Ann Arbor, MI (United States)

    2012-07-15

    Purpose: We investigated the clinical and dosimetric predictors for radiation-associated femoral fractures in patients with proximal lower extremity soft tissue sarcomas (STS). Methods and Materials: We examined 131 patients with proximal lower extremity STS who received limb-sparing surgery and external-beam radiation therapy between 1985 and 2006. Five (4%) patients sustained pathologic femoral fractures. Dosimetric analysis was limited to 4 fracture patients with full three-dimensional dose information, who were compared with 59 nonfracture patients. The mean doses and volumes of bone (V{sub d}) receiving specified doses ({>=}30 Gy, 45 Gy, 60 Gy) at the femoral body, femoral neck, intertrochanteric region, and subtrochanteric region were compared. Clinical predictive factors were also evaluated. Results: Of 4 fracture patients in our dosimetric series, there were three femoral neck fractures with a mean dose of 57.6 {+-} 8.9 Gy, V30 of 14.5 {+-} 2.3 cc, V45 of 11.8 {+-} 1.1 cc, and V60 of 7.2 {+-} 2.2 cc at the femoral neck compared with 22.9 {+-} 20.8 Gy, 4.8 {+-} 5.6 cc, 2.5 {+-} 3.9 cc, and 0.8 {+-} 2.7 cc, respectively, for nonfracture patients (p < 0.03 for all). The femoral neck fracture rate was higher than at the subtrochanteric region despite lower mean doses at these subregions. All fracture sites received mean doses greater than 40 Gy. Also, with our policy of prophylactic femoral intramedullary nailing for high-risk patients, there was no significant difference in fracture rates between patients with and without periosteal excision. There were no significant differences in age, sex, tumor size, timing of radiation therapy, and use of chemotherapy between fracture and nonfracture patients. Conclusions: These dose-volume toxicity relationships provide RT optimization goals to guide future efforts for reducing pathologic fracture rates. Prophylactic femoral intramedullary nailing may also reduce fracture risk for susceptible patients.

  10. Development of autonomous gamma dose logger for environmental monitoring

    SciTech Connect (OSTI)

    Jisha, N. V.; Krishnakumar, D. N.; Surya Prakash, G.; Kumari, Anju; Baskaran, R.; Venkatraman, B.

    2012-03-15

    Continuous monitoring and archiving of background radiation levels in and around the nuclear installation is essential and the data would be of immense use during analysis of any untoward incidents. A portable Geiger Muller detector based autonomous gamma dose logger (AGDL) for environmental monitoring is indigenously designed and developed. The system operations are controlled by microcontroller (AT89S52) and the main features of the system are software data acquisition, real time LCD display of radiation level, data archiving at removable compact flash card. The complete system operates on 12 V battery backed up by solar panel and hence the system is totally portable and ideal for field use. The system has been calibrated with Co-60 source (8.1 MBq) at various source-detector distances. The system is field tested and performance evaluation is carried out. This paper covers the design considerations of the hardware, software architecture of the system along with details of the front-end operation of the autonomous gamma dose logger and the data file formats. The data gathered during field testing and inter comparison with GammaTRACER are also presented in the paper. AGDL has shown excellent correlation with energy fluence monitor tuned to identify {sup 41}Ar, proving its utility for real-time plume tracking and source term estimation.

  11. Hanford Technical Basis for Multiple Dosimetry Effective Dose Methodology

    SciTech Connect (OSTI)

    Hill, Robin L.; Rathbone, Bruce A.

    2010-08-01

    The current method at Hanford for dealing with the results from multiple dosimeters worn during non-uniform irradiation is to use a compartmentalization method to calculate the effective dose (E). The method, as documented in the current version of Section 6.9.3 in the 'Hanford External Dosimetry Technical Basis Manual, PNL-MA-842,' is based on the compartmentalization method presented in the 1997 ANSI/HPS N13.41 standard, 'Criteria for Performing Multiple Dosimetry.' With the adoption of the ICRP 60 methodology in the 2007 revision to 10 CFR 835 came changes that have a direct affect on the compartmentalization method described in the 1997 ANSI/HPS N13.41 standard, and, thus, to the method used at Hanford. The ANSI/HPS N13.41 standard committee is in the process of updating the standard, but the changes to the standard have not yet been approved. And, the drafts of the revision of the standard tend to align more with ICRP 60 than with the changes specified in the 2007 revision to 10 CFR 835. Therefore, a revised method for calculating effective dose from non-uniform external irradiation using a compartmental method was developed using the tissue weighting factors and remainder organs specified in 10 CFR 835 (2007).

  12. Comparison of 3D dose distributions for HDR {sup 192}Ir brachytherapy sources with normoxic polymer gel dosimetry and treatment planning system

    SciTech Connect (OSTI)

    Senkesen, Oznur; Tezcanli, Evrim; Buyuksarac, Bora; Ozbay, Ismail

    2014-10-01

    Radiation fluence changes caused by the dosimeter itself and poor spatial resolution may lead to lack of 3-dimensional (3D) information depending on the features of the dosimeter and quality assurance of dose distributions for highdose rate (HDR) iridium-192 ({sup 192}Ir) brachytherapy sources is challenging and experimental dosimetry methods used for brachytherapy sources are limited. In this study, we investigated 3D dose distributions of {sup 192}Ir brachytherapy sources for irradiation with single and multiple dwell positions using a normoxic gel dosimeter and compared them with treatment planning system (TPS) calculations. For dose calibration purposes, 100-mL gel-containing vials were irradiated at predefined doses and then scanned in an magnetic resonance (MR) imaging unit. Gel phantoms prepared in 2 spherical glasses were irradiated with {sup 192}Ir for the calculated dwell positions, and MR scans of the phantoms were obtained. The images were analyzed with MATLAB software. Dose distributions and profiles derived with 1-mm resolution were compared with TPS calculations. Linearity was observed between the delivered dose and the reciprocal of the T2 relaxation time constant of the gel. The x-, y-, and z-axes were defined as the sagittal, coronal, and axial planes, respectively, the sagittal and axial planes were defined parallel to the long axis of the source while the coronal plane was defined horizontally to the long axis of the source. The differences between measured and calculated profile widths of 3-cm source length and point source for 70%, 50%, and 30% isodose lines were evaluated at 3 dose levels using 18 profiles of comparison. The calculations for 3-cm source length revealed a difference of > 3 mm in 1 coordinate at 50% profile width on the sagittal plane and 3 coordinates at 70% profile width and 2 coordinates at 50% and 30% profile widths on the axial plane. Calculations on the coronal plane for 3-cm source length showed > 3-mm difference in 1 coordinate at 50% and 70% and 2 coordinates at 30% profile widths. The point source measurements and calculations for 50% profile widths revealed a difference > 3 mm in 1 coordinate on the sagittal plane and 2 coordinates on the axial plane. The doses of 3 coordinates on the sagittal plane and 4 coordinates on the axial plane could not be evaluated in 30% profile width because of low doses. There was good agreement between the gel dosimetry and TPS results. Gel dosimetry provides dose distributions in all 3 planes at the same time, which enables us to define the dose distributions in any plane with high resolution. It can be used to obtain 3D dose distributions for HDR {sup 192}Ir brachytherapy sources and 3D dose verification of TPS.

  13. Microsoft PowerPoint - Low Dose Update Metting 6 Dec 2012

    Office of Environmental Management (EM)

    Low Dose DOE's Low Dose R di ti R h R di ti R h Radiation Research Radiation Research Program Program g g NF Metting, Sc.D., Program Manager Nuclear Energy Advisory Committee Meeting Nuclear Energy Advisory Committee Meeting L'Enfant Plaza Hotel L'Enfant Plaza Hotel 6 December 2012 Office of Science Office of Biological and Environmental Research DOE's Low Dose Program: DOE s Low Dose Program: Is unique within the U.S. government in focusing on low dose biological research aimed at informing

  14. Widget:UtilityRateNamingHelper | Open Energy Information

    Open Energy Info (EERE)

    UtilityRateNamingHelper Jump to: navigation, search This widget displays the utility rate database form. For example: Widget:UtilityRateNamingHelper Retrieved from "http:...

  15. MO-PIS-Exhibit Hall-01: Imaging: CT Dose Optimization Technologies I

    SciTech Connect (OSTI)

    Denison, K; Smith, S

    2014-06-15

    Partners in Solutions is an exciting new program in which AAPM partners with our vendors to present practical hands-on information about the equipment and software systems that we use in our clinics. The imaging topic this year is CT scanner dose optimization capabilities. Note that the sessions are being held in a special purpose room built on the Exhibit Hall Floor, to encourage further interaction with the vendors. Dose Optimization Capabilities of GE Computed Tomography Scanners Presentation Time: 11:15 11:45 AM GE Healthcare is dedicated to the delivery of high quality clinical images through the development of technologies, which optimize the application of ionizing radiation. In computed tomography, dose management solutions fall into four categories: employs projection data and statistical modeling to decrease noise in the reconstructed image - creating an opportunity for mA reduction in the acquisition of diagnostic images. Veo represents true Model Based Iterative Reconstruction (MBiR). Using high-level algorithms in tandem with advanced computing power, Veo enables lower pixel noise standard deviation and improved spatial resolution within a single image. Advanced Adaptive Image Filters allow for maintenance of spatial resolution while reducing image noise. Examples of adaptive image space filters include Neuro 3-D filters and Cardiac Noise Reduction Filters. AutomA adjusts mA along the z-axis and is the CT equivalent of auto exposure control in conventional x-ray systems. Dynamic Z-axis Tracking offers an additional opportunity for dose reduction in helical acquisitions while SmartTrack Z-axis Tracking serves to ensure beam, collimator and detector alignment during tube rotation. SmartmA provides angular mA modulation. ECG Helical Modulation reduces mA during the systolic phase of the heart cycle. SmartBeam optimization uses bowtie beam-shaping hardware and software to filter off-axis x-rays - minimizing dose and reducing x-ray scatter. The DICOM Radiation Dose Structured Report (RDSR) generates a dose report at the conclusion of every examination. Dose Check preemptively notifies CT operators when scan parameters exceed user-defined dose thresholds. DoseWatch is an information technology application providing vendor-agnostic dose tracking and analysis for CT (and all other diagnostic x-ray modalities) SnapShot Pulse improves coronary CTA dose management. VolumeShuttle uses two acquisitions to increase coverage, decrease dose, and conserve on contrast administration. Color-Coding for Kids applies the Broselow-Luten Pediatric System to facilitate pediatric emergency care and reduce medical errors. FeatherLight achieves dose optimization through pediatric procedure-based protocols. Adventure Series scanners provide a child-friendly imaging environment promoting patient cooperation with resultant reduction in retakes and patient motion. Philips CT Dose Optimization Tools and Advanced Reconstruction Presentation Time: 11:45 12:15 PM The first part of the talk will cover Dose Reduction and Dose Optimization Technologies present in Philips CT Scanners. The main Technologies to be presented include: DoseRight and tube current modulation (DoseRight, Z-DOM, 3D-DOM, DoseRight Cardiac) Special acquisition modes Beam filtration and beam shapers Eclipse collimator and ClearRay collimator NanoPanel detector DoseRight will cover automatic tube current selection that automatically adjusts the dose for the individual patient. The presentation will explore the modulation techniques currently employed in Philips CT scanners and will include the algorithmic concepts as well as illustrative examples. Modulation and current selection technologies to be covered include the Automatic Current Selection component of DoseRight, ZDOM longitudinal dose modulation, 3D-DOM (combination of longitudinal and rotational dose modulation), Cardiac Dose right (an ECG based dose modulation scheme), and the DoseRight Index (DRI) IQ index. The special acquisition modes covers acquisition techniques such as prospective gating that

  16. Analytical Improvements in PV Degradation Rate Determination

    SciTech Connect (OSTI)

    Jordan, D. C.; Kurtz, S. R.

    2011-02-01

    As photovoltaic (PV) penetration of the power grid increases, it becomes vital to know how decreased power output may affect cost over time. In order to predict power delivery, the decline or degradation rates must be determined accurately. For non-spectrally corrected data several complete seasonal cycles (typically 3-5 years) are required to obtain reasonably accurate degradation rates. In a rapidly evolving industry such a time span is often unacceptable and the need exists to determine degradation rates accurately in a shorter period of time. Occurrence of outliers and data shifts are two examples of analytical problems leading to greater uncertainty and therefore to longer observation times. In this paper we compare three methodologies of data analysis for robustness in the presence of outliers, data shifts and shorter measurement time periods.

  17. Aqueous Corrosion Rates for Waste Package Materials

    SciTech Connect (OSTI)

    S. Arthur

    2004-10-08

    The purpose of this analysis, as directed by ''Technical Work Plan for: Regulatory Integration Modeling and Analysis of the Waste Form and Waste Package'' (BSC 2004 [DIRS 171583]), is to compile applicable corrosion data from the literature (journal articles, engineering documents, materials handbooks, or standards, and national laboratory reports), evaluate the quality of these data, and use these to perform statistical analyses and distributions for aqueous corrosion rates of waste package materials. The purpose of this report is not to describe the performance of engineered barriers for the TSPA-LA. Instead, the analysis provides simple statistics on aqueous corrosion rates of steels and alloys. These rates are limited by various aqueous parameters such as temperature (up to 100 C), water type (i.e., fresh versus saline), and pH. Corrosion data of materials at pH extremes (below 4 and above 9) are not included in this analysis, as materials commonly display different corrosion behaviors under these conditions. The exception is highly corrosion-resistant materials (Inconel Alloys) for which rate data from corrosion tests at a pH of approximately 3 were included. The waste package materials investigated are those from the long and short 5-DHLW waste packages, 2-MCO/2-DHLW waste package, and the 21-PWR commercial waste package. This analysis also contains rate data for some of the materials present inside the fuel canisters for the following fuel types: U-Mo (Fermi U-10%Mo), MOX (FFTF), Thorium Carbide and Th/U Carbide (Fort Saint Vrain [FSVR]), Th/U Oxide (Shippingport LWBR), U-metal (N Reactor), Intact U-Oxide (Shippingport PWR, Commercial), aluminum-based, and U-Zr-H (TRIGA). Analysis of corrosion rates for Alloy 22, spent nuclear fuel, defense high level waste (DHLW) glass, and Titanium Grade 7 can be found in other analysis or model reports.

  18. Calculation of Ambient (H*(10)) and Personal (Hp(10)) Dose Equivalent from a 252Cf Neutron Source

    SciTech Connect (OSTI)

    Traub, Richard J.

    2010-03-26

    The purpose of this calculation is to calculate the neutron dose factors for the Sr-Cf-3000 neutron source that is located in the 318 low scatter room (LSR). The dose factors were based on the dose conversion factors published in ICRP-21 Appendix 6, and the Ambient dose equivalent (H*(10)) and Personal dose equivalent (Hp(10)) dose factors published in ICRP Publication 74.

  19. DOE - NNSA/NFO -- Rate our Site

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

    Rate our Site U.S. DOE/NNSA - Nevada Field Office Rate our website The Nevada Field Office is committed to providing high-quality products and services that meet your needs. Your participation in our customer satisfaction survey will help us achieve this goal. NFO would appreciate your taking the time to complete this survey. Responses are confidential. The survey should take approximately 15 minutes or 1 minute per question. You do not have to answers all the questions. How did you feel working

  20. Implications of Intercellular Signaling for Radiation Therapy: A Theoretical Dose-Planning Study

    SciTech Connect (OSTI)

    McMahon, Stephen J.; McGarry, Conor K.; Butterworth, Karl T.; O'Sullivan, Joe M.; Hounsell, Alan R.; Prise, Kevin M.

    2013-12-01

    Purpose: Recent in vitro results have shown significant contributions to cell killing from signaling effects at doses that are typically used in radiation therapy. This study investigates whether these in vitro observations can be reconciled with in vivo knowledge and how signaling may have an impact on future developments in radiation therapy. Methods and Materials: Prostate cancer treatment plans were generated for a series of 10 patients using 3-dimensional conformal therapy, intensity modulated radiation therapy (IMRT), and volumetric modulated arc therapy techniques. These plans were evaluated using mathematical models of survival following modulated radiation exposures that were developed from in vitro observations and incorporate the effects of intercellular signaling. The impact on dosevolume histograms and mean doses were evaluated by converting these survival levels into signaling-adjusted doses for comparison. Results: Inclusion of intercellular communication leads to significant differences between the signalling-adjusted and physical doses across a large volume. Organs in low-dose regions near target volumes see the largest increases, with mean signaling-adjusted bladder doses increasing from 23 to 33 Gy in IMRT plans. By contrast, in high-dose regions, there is a small decrease in signaling-adjusted dose due to reduced contributions from neighboring cells, with planning target volume mean doses falling from 74 to 71 Gy in IMRT. Overall, however, the dose distributions remain broadly similar, and comparisons between the treatment modalities are largely unchanged whether physical or signaling-adjusted dose is compared. Conclusions: Although incorporating cellular signaling significantly affects cell killing in low-dose regions and suggests a different interpretation for many phenomena, their effect in high-dose regions for typical planning techniques is comparatively small. This indicates that the significant signaling effects observed in vitro are not contradicted by comparison with clinical observations. Future investigations are needed to validate these effects in vivo and to quantify their ranges and potential impact on more advanced radiation therapy techniques.

  1. DOE-HDBK-1122-99; Radiological Control Technician Training

    Office of Environmental Management (EM)

    Instructor's Guide 2.17-1 Course Title: Radiological Control Technician Module Title: Contamination Monitoring Instrumentation Module Number: 2.17 Objectives: 2.17.01 List the factors which affects an RCT's selection of a portable contamination monitoring instrument. L 2.17.02 Describe the following features and specifications for commonly used count rate meter probes used at your site for beta/gamma and/or alpha surveys: a. Detector type b. Detector shielding and window c. Types of radiation

  2. DOE-HDBK-1122-99; Radiological Control Technician Training

    Office of Environmental Management (EM)

    Study Guide 2.17-1 Course Title: Radiological Control Technician Module Title: Contamination Monitoring Instrumentation Module Number: 2.17 Objectives: 2.17.01 List the factors which affects an RCT's selection of a portable contamination monitoring instrument. i 2.17.02 Describe the following features and specifications for commonly used count rate meter probes used at your site for beta/gamma and/or alpha surveys: a. Detector type b. Detector shielding and window c. Types of radiation

  3. Radiation doses in cone-beam breast computed tomography: A Monte Carlo simulation study

    SciTech Connect (OSTI)

    Yi Ying; Lai, Chao-Jen; Han Tao; Zhong Yuncheng; Shen Youtao; Liu Xinming; Ge Shuaiping; You Zhicheng; Wang Tianpeng; Shaw, Chris C.

    2011-02-15

    Purpose: In this article, we describe a method to estimate the spatial dose variation, average dose and mean glandular dose (MGD) for a real breast using Monte Carlo simulation based on cone beam breast computed tomography (CBBCT) images. We present and discuss the dose estimation results for 19 mastectomy breast specimens, 4 homogeneous breast models, 6 ellipsoidal phantoms, and 6 cylindrical phantoms. Methods: To validate the Monte Carlo method for dose estimation in CBBCT, we compared the Monte Carlo dose estimates with the thermoluminescent dosimeter measurements at various radial positions in two polycarbonate cylinders (11- and 15-cm in diameter). Cone-beam computed tomography (CBCT) images of 19 mastectomy breast specimens, obtained with a bench-top experimental scanner, were segmented and used to construct 19 structured breast models. Monte Carlo simulation of CBBCT with these models was performed and used to estimate the point doses, average doses, and mean glandular doses for unit open air exposure at the iso-center. Mass based glandularity values were computed and used to investigate their effects on the average doses as well as the mean glandular doses. Average doses for 4 homogeneous breast models were estimated and compared to those of the corresponding structured breast models to investigate the effect of tissue structures. Average doses for ellipsoidal and cylindrical digital phantoms of identical diameter and height were also estimated for various glandularity values and compared with those for the structured breast models. Results: The absorbed dose maps for structured breast models show that doses in the glandular tissue were higher than those in the nearby adipose tissue. Estimated average doses for the homogeneous breast models were almost identical to those for the structured breast models (p=1). Normalized average doses estimated for the ellipsoidal phantoms were similar to those for the structured breast models (root mean square (rms) percentage difference=1.7%; p=0.01), whereas those for the cylindrical phantoms were significantly lower (rms percentage difference=7.7%; p<0.01). Normalized MGDs were found to decrease with increasing glandularity. Conclusions: Our results indicate that it is sufficient to use homogeneous breast models derived from CBCT generated structured breast models to estimate the average dose. This investigation also shows that ellipsoidal digital phantoms of similar dimensions (diameter and height) and glandularity to actual breasts may be used to represent a real breast to estimate the average breast dose with Monte Carlo simulation. We have also successfully demonstrated the use of structured breast models to estimate the true MGDs and shown that the normalized MGDs decreased with the glandularity as previously reported by other researchers for CBBCT or mammography.

  4. Iterative methods for dose reduction and image enhancement in tomography

    DOE Patents [OSTI]

    Miao, Jianwei; Fahimian, Benjamin Pooya

    2012-09-18

    A system and method for creating a three dimensional cross sectional image of an object by the reconstruction of its projections that have been iteratively refined through modification in object space and Fourier space is disclosed. The invention provides systems and methods for use with any tomographic imaging system that reconstructs an object from its projections. In one embodiment, the invention presents a method to eliminate interpolations present in conventional tomography. The method has been experimentally shown to provide higher resolution and improved image quality parameters over existing approaches. A primary benefit of the method is radiation dose reduction since the invention can produce an image of a desired quality with a fewer number projections than seen with conventional methods.

  5. SU-E-T-403: Measurement of the Neutron Ambient Dose Equivalent From the TrueBeam Linac Head and Varian 2100 Clinac

    SciTech Connect (OSTI)

    Harvey, M; Pollard, J; Wen, Z; Gao, S

    2014-06-01

    Purpose: High-energy x-ray therapy produces an undesirable source of stray neutron dose to healthy tissues, and thus, poses a risk for second cancer induction years after the primary treatment. Hence, the purpose of this study was to measure the neutron ambient dose equivalent, H*(10), produced from the TrueBeam and Varian 2100 linac heads, respectively. Of particular note is that there is no measured data available in the literature on H*(10) production from the TrueBeam treatment head. Methods: Both linacs were operated in flattening filter mode using a 15 MV x-ray beam on TrueBeam and an 18 MV x-ray beam for the Varian 2100 Clinac with the jaws and multileaf collimators in the fully closed position. A dose delivery rate of 600 MU/min was delivered on the TrueBeam and the Varian 2100 Clinac, respectively and the H*(10) rate was measured in triplicate using the WENDI-2 detector located at multiple positions including isocenter and longitudinal (gun-target) to the isocenter. Results: For each measurement, the H*(10) rate was relatively constant with increasing distance away from the isocenter with standard deviations on the order of a tenth of a mSv/h or less for the given beam energy. In general, fluctuations in the longitudinal H*(10) rate between the anterior-posterior couch directions were approximately a percent for both beam energies. Conclusion: Our preliminary results suggest an H*(10) rate of about 30 mSv/h (40 mSv/h) or less for TrueBeam (Varian Clinac 2100) for all measurements considered in this study indicating a relatively low contribution of produced secondary neutrons to the primary therapeutic beam.

  6. Front-end utility rate updates | OpenEI Community

    Open Energy Info (EERE)

    Front-end utility rate updates Home > Groups > Utility Rate Rmckeel's picture Submitted by Rmckeel(297) Contributor 13 February, 2013 - 14:28 Utility Rates A few utility rate...

  7. Overview of Field Experience - Degradation Rates & Lifetimes

    SciTech Connect (OSTI)

    Jordan, Dirk; Kurtz, Sarah

    2015-09-14

    The way a PV module fails may depend not only on its design and the materials used in its construction, but also on the weather it experiences, the way it is mounted, and the quality control during its manufacture. This presentation gives an overview of Field Experience - what degradation rates and what lifetimes are being observed in various regions.

  8. The Distant Type Ia Supernova Rate

    DOE R&D Accomplishments [OSTI]

    Pain, R.; Fabbro, S.; Sullivan, M.; Ellis, R. S.; Aldering, G.; Astier, P.; Deustua, S. E.; Fruchter, A. S.; Goldhaber, G.; Goobar, A.; Groom, D. E.; Hardin, D.; Hook, I. M.; Howell, D. A.; Irwin, M. J.; Kim, A. G.; Kim, M. Y.; Knop, R. A.; Lee, J. C.; Perlmutter, S.; Ruiz-Lapuente, P.; Schahmaneche, K.; Schaefer, B.; Walton, N. A.

    2002-05-28

    We present a measurement of the rate of distant Type Ia supernovae derived using 4 large subsets of data from the Supernova Cosmology Project. Within this fiducial sample, which surveyed about 12 square degrees, thirty-eight supernovae were detected at redshifts 0.25--0.85. In a spatially flat cosmological model consistent with the results obtained by the Supernova Cosmology Project, we derive a rest-frame Type Ia supernova rate at a mean red shift z {approx_equal} 0.55 of 1.53 {sub -0.25}{sub -0.31}{sup 0.28}{sup 0.32} x 10{sup -4} h{sup 3} Mpc{sup -3} yr{sup -1} or 0.58{sub -0.09}{sub -0.09}{sup +0.10}{sup +0.10} h{sup 2} SNu(1 SNu = 1 supernova per century per 10{sup 10} L{sub B}sun), where the first uncertainty is statistical and the second includes systematic effects. The dependence of the rate on the assumed cosmological parameters is studied and the redshift dependence of the rate per unit comoving volume is contrasted with local estimates in the context of possible cosmic star formation histories and progenitor models.

  9. WP-96/TR-96 & TC-96 Power and Transmission Rate Case (rates/ratecases...

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

    Of Decision (WP-96 ROD) Final Studies And Documentation (WP-96-FS) Loads and Resources Revenue Requirement Segmentation Marginal Cost Analysis Wholesale Power Rate Development...

  10. U.S. Utility Rate Database - U.S. Utility Rate Database

    Open Energy Info (EERE)

    As Of Today ApprovedUnapproved All Approved Only Unapproved Only Order By Latest Update Utility Name Rate Name Sector Approval Staus Effective Date End Date Display Results...

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

    SciTech Connect (OSTI)

    Yu, Victoria; Kishan, Amar U.; Cao, Minsong; Low, Daniel; Lee, Percy; Ruan, Dan

    2014-03-15

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

  12. EMP Attachment 3 DOE-SC PNNL Site Dose Assessment Guidance

    SciTech Connect (OSTI)

    Snyder, Sandra F.

    2011-12-21

    This Dose Assessment Guidance (DAG) describes methods to use to determine the Maximally-Exposed Individual (MEI) location and to estimate dose impact to that individual under the U.S. Department of Energy Office of Science (DOE-SC) Pacific Northwest National Laboratory (PNNL) Site Environmental Monitoring Plan (EMP). This guidance applies to public dose from radioactive material releases to the air from PNNL Site operations. This document is an attachment to the Pacific Northwest National Laboratory (PNNL) Environmental Monitoring Plan (EMP) and describes dose assessment guidance for radiological air emissions. The impact of radiological air emissions from the U.S. Department of Energy Office of Science (DOE-SC) PNNL Site is indicated by dose estimates to a maximally exposed member of the public, referred to as the maximally exposed individual (MEI). Reporting requirements associated with dose to members of the public from radiological air emissions are in 40 CFR Part 61.94, WAC 246-247-080, and DOE Order 458.1. The DOE Order and state standards for dose from radioactive air emissions are consistent with U.S. Environmental Protection Agency (EPA) dose standards in 40 CFR 61.92 (i.e., 10 mrem/yr to a MEI). Despite the fact that the current Contract Requirements Document (CRD) for the DOE-SC PNNL Site operations does not include the requirement to meet DOE CRD 458.1, paragraph 2.b, public dose limits, the DOE dose limits would be met when EPA limits are met.

  13. Impact of x-ray dose on the response of CR-39 to 1–5.5 MeV alphas

    SciTech Connect (OSTI)

    Rojas-Herrera, J.; Rinderknecht, H. G.; Zylstra, A. B.; Gatu Johnson, M.; Orozco, D.; Rosenberg, M. J.; Sio, H.; Seguin, F. H.; Frenje, J. A.; Li, C. K.; Petrasso, R. D.

    2015-03-01

    The CR-39 nuclear track detector is used in many nuclear diagnostics fielded at inertial confinement fusion (ICF) facilities. Large x-ray uences generated by ICF experiments may impact the CR-39 response to incident charged particles. To determine the impact of x-ray exposure on the CR-39 response to alpha particles, a thick-target bremsstrahlung x-ray generator was used to expose CR-39 to various doses of 8 keV Cu-Kα and Kβ x-rays. The CR-39 detectors were then exposed to 1-5.5 MeV alphas from an Am-241 source. The regions of the CR-39 exposed to x-rays showed a smaller track diameter than those not exposed to x-rays: for example, a dose of 3.0 ± 0.1 Gy causes a decrease of (19 ± 2)% in the track diameter of a 5.5 MeV alpha particle, while a dose of 60.0 ± 1.3 Gy results in a decrease of (45 ± 5)% in the track diameter. The reduced track diameters were found to be predominantly caused by a comparable reduction in the bulk etch rate of the CR-39 with x-ray dose. A residual effect depending on alpha particle energy is characterized using an empirical formula.

  14. Human dose assessment for the radionuclides {sup 90}Sr and {sup 90}Y at TA-35 SWMU 35-003 (r) and Ten Site Canyon

    SciTech Connect (OSTI)

    Jarmer, D.; Lyman, J.

    1997-07-01

    This report gives an estimate of the radiological dose to an individual living on or working at a site contaminated with strontium-90 ({sup 90}Sr) and yttrium-90 ({sup 90}Y). The site consists of a small receiving canyon that drains into Ten-Site Canyon at the eastern end of Los Alamos National Laboratory`s technical area 35 (TA-35). Between 1951 and 1963 a wastewater treatment facility located at TA-35 discharged water containing {sup 90}Sr and {sup 90}Y to this receiving canyon. The authors used the RESRAD computer code to calculate the dose to an on-site individual, based on two exposure scenarios: (1) a person working at the site for eight hours a day, five days a week, for twenty-five years and (2) a farmer living at the site twenty four hours a day, seven days a week, for thirty years. The exposure pathways considered were direct exposure to external radiation; inhalation of contaminated dusts; and ingestion of plants, water, and soil. The authors found that the maximum estimated dose rates were 1 and 21 mrem y{sup {minus}1} for the worker and farmer scenarios respectively. The authors have concluded that the value for the worker scenario is well below the DOE dose limit of 100 mrem y{sup {minus}1} but the farmer is overexposed.

  15. Impact of x-ray dose on the response of CR-39 to 1–5.5 MeV alphas

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

    Rojas-Herrera, J.; Rinderknecht, H. G.; Zylstra, A. B.; Gatu Johnson, M.; Orozco, D.; Rosenberg, M. J.; Sio, H.; Seguin, F. H.; Frenje, J. A.; Li, C. K.; et al

    2015-03-01

    The CR-39 nuclear track detector is used in many nuclear diagnostics fielded at inertial confinement fusion (ICF) facilities. Large x-ray uences generated by ICF experiments may impact the CR-39 response to incident charged particles. To determine the impact of x-ray exposure on the CR-39 response to alpha particles, a thick-target bremsstrahlung x-ray generator was used to expose CR-39 to various doses of 8 keV Cu-Kα and Kβ x-rays. The CR-39 detectors were then exposed to 1-5.5 MeV alphas from an Am-241 source. The regions of the CR-39 exposed to x-rays showed a smaller track diameter than those not exposed tomore » x-rays: for example, a dose of 3.0 ± 0.1 Gy causes a decrease of (19 ± 2)% in the track diameter of a 5.5 MeV alpha particle, while a dose of 60.0 ± 1.3 Gy results in a decrease of (45 ± 5)% in the track diameter. The reduced track diameters were found to be predominantly caused by a comparable reduction in the bulk etch rate of the CR-39 with x-ray dose. A residual effect depending on alpha particle energy is characterized using an empirical formula.« less

  16. Impact of x-ray dose on the response of CR-39 to 15.5 MeV alphas

    SciTech Connect (OSTI)

    Rojas-Herrera, J.; Rinderknecht, H. G.; Zylstra, A. B.; Gatu Johnson, M.; Orozco, D.; Rosenberg, M. J.; Sio, H.; Seguin, F. H.; Frenje, J. A.; Li, C. K.; Petrasso, R. D.

    2015-03-01

    The CR-39 nuclear track detector is used in many nuclear diagnostics #12;fielded at inertial con#12;nement fusion (ICF) facilities. Large x-ray uences generated by ICF experiments may impact the CR-39 response to incident charged particles. To determine the impact of x-ray exposure on the CR-39 response to alpha particles, a thick-target bremsstrahlung x-ray generator was used to expose CR-39 to various doses of 8 keV Cu-K?#11; and K#12;? x-rays. The CR-39 detectors were then exposed to 1-5.5 MeV alphas from an Am-241 source. The regions of the CR-39 exposed to x-rays showed a smaller track diameter than those not exposed to x-rays: for example, a dose of 3.0#6; 0.1 Gy causes a decrease of (19 #6;2)% in the track diameter of a 5.5 MeV alpha particle, while a dose of 60.0 #6;1.3 Gy results in a decrease of (45 #6;5)% in the track diameter. The reduced track diameters were found to be predominantly caused by a comparable reduction in the bulk etch rate of the CR-39 with x-ray dose. A residual eff#11;ect depending on alpha particle energy is characterized using an empirical formula.

  17. A Reanalysis of Curvature in the Dose Response for Cancer and Modifications by Age at Exposure Following Radiation Therapy for Benign Disease

    SciTech Connect (OSTI)

    Little, Mark P.; Stovall, Marilyn; Smith, Susan A.; Kleinerman, Ruth A.

    2013-02-01

    Purpose: To assess the shape of the dose response for various cancer endpoints and modifiers by age and time. Methods and Materials: Reanalysis of the US peptic ulcer data testing for heterogeneity of radiogenic risk by cancer endpoint (stomach, pancreas, lung, leukemia, all other). Results: There are statistically significant (P<.05) excess risks for all cancer and for lung cancer and borderline statistically significant risks for stomach cancer (P=.07), and leukemia (P=.06), with excess relative risks Gy{sup -1} of 0.024 (95% confidence interval [CI] 0.011, 0.039), 0.559 (95% CI 0.221, 1.021), 0.042 (95% CI -0.002, 0.119), and 1.087 (95% CI -0.018, 4.925), respectively. There is statistically significant (P=.007) excess risk of pancreatic cancer when adjusted for dose-response curvature. General downward curvature is apparent in the dose response, statistically significant (P<.05) for all cancers, pancreatic cancer, and all other cancers (ie, other than stomach, pancreas, lung, leukemia). There are indications of reduction in relative risk with increasing age at exposure (for all cancers, pancreatic cancer), but no evidence for quadratic variations in relative risk with age at exposure. If a linear-exponential dose response is used, there is no significant heterogeneity in the dose response among the 5 endpoints considered or in the speed of variation of relative risk with age at exposure. The risks are generally consistent with those observed in the Japanese atomic bomb survivors and in groups of nuclear workers. Conclusions: There are excess risks for various malignancies in this data set. Generally there is a marked downward curvature in the dose response and significant reduction in relative risk with increasing age at exposure. The consistency of risks with those observed in the Japanese atomic bomb survivors and in groups of nuclear workers implies that there may be little sparing effect of fractionation of dose or low-dose-rate exposure.

  18. The effects of repeated low-dose sarin exposure

    SciTech Connect (OSTI)

    Shih, T.-M. . E-mail: tsungming.a.shih@us.army.mil; Hulet, S.W.; McDonough, J.H.

    2006-09-01

    This project assessed the effects of repeated low-dose exposure of guinea pigs to the organophosphorus nerve agent sarin. Animals were injected once a day, 5 days per week (Monday-Friday), for 2 weeks with fractions (0.3x, 0.4x, 0.5x, or 0.6x) of the established LD{sub 5} dose of sarin (42 {mu}g/kg, s.c.). The animals were assessed for changes in body weight, red blood cell (RBC) acetylcholinesterase (AChE) levels, neurobehavioral reactions to a functional observational battery (FOB), cortical electroencephalographic (EEG) power spectrum, and intrinsic acetylcholine (ACh) neurotransmitter (NT) regulation over the 2 weeks of sarin exposure and for up to 12 days postinjection. No guinea pig receiving 0.3, 0.4 or 0.5 x LD{sub 5} of sarin showed signs of cortical EEG seizures despite decreases in RBC AChE levels to as low as 10% of baseline, while seizures were evident in animals receiving 0.6 x LD{sub 5} of sarin as early as the second day; subsequent injections led to incapacitation and death. Animals receiving 0.5 x LD{sub 5} sarin showed obvious signs of cholinergic toxicity; overall, 2 of 13 animals receiving 0.5 x LD{sub 5} sarin died before all 10 injections were given, and there was a significant increase in the angle of gait in the animals that lived. By the 10th day of injection, the animals receiving saline were significantly easier to remove from their cages and handle and significantly less responsive to an approaching pencil and touch on the rump in comparison with the first day of testing. In contrast, the animals receiving 0.4 x LD{sub 5} sarin failed to show any significant reductions in their responses to an approaching pencil and a touch on the rump as compared with the first day. The 0.5 x LD{sub 5} sarin animals also failed to show any significant changes to the approach and touch responses and did not adjust to handling or removal from the cage from the first day of injections to the last day of handling. Thus, the guinea pigs receiving the 0.4 and 0.5 x LD{sub 5} doses of sarin failed to habituate to some aspects of neurobehavioral testing. Spectral analysis of EEG data suggested that repeated sarin exposure may disrupt normal sleeping patterns (i.e., lower frequency bandwidths). While these EEG changes returned to relative normalcy 6 days after the last injection in animals receiving 0.4 x LD{sub 5} sarin, these changes were still observed in the animals that received 0.5 x LD{sub 5} sarin. Ten to twelve days after the last sarin injection (in 0.4 x LD{sub 5} group only), neurochemical data showed that striatal choline levels were reduced in comparison to the saline group. At this time, atropine sulfate (5 mg/kg, i.p.) challenge resulted in a transient elevation in striatal ACh levels in animals exposed to repeated 0.4 x LD{sub 5} sarin as well as in control animals. No evidence of brain or heart pathology was found in any guinea pig that survived all 10 sarin injections.

  19. The impact of low-Z and high-Z metal implants in IMRT: A Monte Carlo study of dose inaccuracies in commercial dose algorithms

    SciTech Connect (OSTI)

    Spadea, Maria Francesca; Verburg, Joost Mathias; Seco, Joao; Baroni, Guido

    2014-01-15

    Purpose: The aim of the study was to evaluate the dosimetric impact of low-Z and high-Z metallic implants on IMRT plans. Methods: Computed tomography (CT) scans of three patients were analyzed to study effects due to the presence of Titanium (low-Z), Platinum and Gold (high-Z) inserts. To eliminate artifacts in CT images, a sinogram-based metal artifact reduction algorithm was applied. IMRT dose calculations were performed on both the uncorrected and corrected images using a commercial planning system (convolution/superposition algorithm) and an in-house Monte Carlo platform. Dose differences between uncorrected and corrected datasets were computed and analyzed using gamma index (P?{sub <1}) and setting 2 mm and 2% as distance to agreement and dose difference criteria, respectively. Beam specific depth dose profiles across the metal were also examined. Results: Dose discrepancies between corrected and uncorrected datasets were not significant for low-Z material. High-Z materials caused under-dosage of 20%25% in the region surrounding the metal and over dosage of 10%15% downstream of the hardware. Gamma index test yielded P?{sub <1}>99% for all low-Z cases; while for high-Z cases it returned 91% < P?{sub <1}< 99%. Analysis of the depth dose curve of a single beam for low-Z cases revealed that, although the dose attenuation is altered inside the metal, it does not differ downstream of the insert. However, for high-Z metal implants the dose is increased up to 10%12% around the insert. In addition, Monte Carlo method was more sensitive to the presence of metal inserts than superposition/convolution algorithm. Conclusions: The reduction in terms of dose of metal artifacts in CT images is relevant for high-Z implants. In this case, dose distribution should be calculated using Monte Carlo algorithms, given their superior accuracy in dose modeling in and around the metal. In addition, the knowledge of the composition of metal inserts improves the accuracy of the Monte Carlo dose calculation significantly.

  20. EDC-37 Deflagration Rates at Elevated Pressures

    SciTech Connect (OSTI)

    Maienschein, J L; Koerner, J G

    2008-01-31

    We report deflagration rates on EDC-37 at high pressures. Experiments are conducted using the Lawrence Livermore National Laboratory High Pressure Strand Burner (HPSB) apparatus. The HPSB contains a deflagrating sample in a small volume, high pressure chamber. The sample consists of nine, 6.35 mm diameter, 6.35 mm length cylinders stacked on end, with burn wires placed between cylinders. Sample deflagration is limited to the cross-sectional surface of the cylinder by coating the cylindrical surface of the tower with Halthane 88-2 epoxy. Sample deflagration is initiated on one end of the tower by a B/KNO{sub 3} and HNS igniter train. Simultaneous temporal pressure history and burn front time of arrival measurements yield the laminar deflagration rate for a range of pressures and provide insight into deflagration uniformity. These measurements are one indicator of overall thermal explosion violence. Specific details of the experiment and the apparatus can be found in the literature.

  1. Feed rate measuring method and system

    DOE Patents [OSTI]

    Novak, James L. (Albuquerque, NM); Wiczer, James J. (Albuquerque, NM)

    1995-01-01

    A system and method are provided for establishing the feed rate of a workpiece along a feed path with respect to a machine device. First and second sensors each having first and second sensing electrodes which are electrically isolated from the workpiece are positioned above, and in proximity to the desired surfaces of the workpiece along a feed path. An electric field is developed between the first and second sensing electrodes of each sensor and capacitance signals are developed which are indicative of the contour of the workpiece. First and second image signals representative of the contour of the workpiece along the feed path are developed by an image processor. The time delay between corresponding portions of the first and second image signals are then used to determine the feed rate based upon the separation of the first and second sensors and the amount of time between corresponding portions of the first and second image signals.

  2. Predict carbonation rate on iron catalyst

    SciTech Connect (OSTI)

    Dry, M.E.

    1980-02-01

    On solely thermodynamic grounds, the main hydrocarbon product of the Fischer-Tropsch reaction should be methane; in practice, however, carbon is frequently produced as well and deposited on the iron catalyst, fouling the active surface sites. South African Coal, Oil and Gas Corp., Ltd.'s experiments with a fluidized Fischer-Tropsch catalyst bed demonstrate that the rate of carbon deposition is strongly dependent on the hydrogen partial pressure in the reactor, much less dependent on the CO pressure, and not affected at all by the pressure of CO/sub 2/. A suggested reaction scheme for the Fischer-Tropsch synthesis explains these observations and provides a basis for a correlation useful in predicting carbon-deposition rates.

  3. Consumers face $5. 9 million rate increase

    SciTech Connect (OSTI)

    Not Available

    1984-11-01

    Testimony at hearings before the Garrison Diversion Compromise Commission claimed that rural consumers in the Upper Midwest could face $5.9 million in electric rate increases if the commission deauthorizes the project and hydroelectric rates go up to pay the costs of the 1944 Pick-Sloan project originally assigned to irrigation. If there is no irrigation development, the revenue that irrigation must raise to repay the $67 million debt assigned to irrigation must be reassigned to hydroelectric power. The commission represents a compromise between supporters and opponents of the Garrison Diversion project. Spokesmen for regional utilities spoke in support of the project as an investment whose costs have escalated because of delays at the expense of economic development in North Dakota.

  4. Feed rate measuring method and system

    DOE Patents [OSTI]

    Novak, J.L.; Wiczer, J.J.

    1995-12-05

    A system and method are provided for establishing the feed rate of a workpiece along a feed path with respect to a machine device. First and second sensors each having first and second sensing electrodes which are electrically isolated from the workpiece are positioned above, and in proximity to the desired surfaces of the workpiece along a feed path. An electric field is developed between the first and second sensing electrodes of each sensor and capacitance signals are developed which are indicative of the contour of the workpiece. First and second image signals representative of the contour of the workpiece along the feed path are developed by an image processor. The time delay between corresponding portions of the first and second image signals are then used to determine the feed rate based upon the separation of the first and second sensors and the amount of time between corresponding portions of the first and second image signals. 18 figs.

  5. Subsurface heaters with low sulfidation rates

    DOE Patents [OSTI]

    John, Randy Carl; Vinegar, Harold J

    2013-12-10

    A system for heating a hydrocarbon containing formation includes a heater having an elongated ferromagnetic metal heater section. The heater is located in an opening in a formation. The heater section is configured to heat the hydrocarbon containing formation. The exposed ferromagnetic metal has a sulfidation rate that goes down with increasing temperature of the heater, when the heater is in a selected temperature range.

  6. Magnetic fields and galactic star formation rates

    SciTech Connect (OSTI)

    Loo, Sven Van; Tan, Jonathan C.; Falle, Sam A. E. G.

    2015-02-10

    The regulation of galactic-scale star formation rates (SFRs) is a basic problem for theories of galaxy formation and evolution: which processes are responsible for making observed star formation rates so inefficient compared to maximal rates of gas content divided by dynamical timescale? Here we study the effect of magnetic fields of different strengths on the evolution of giant molecular clouds (GMCs) within a kiloparsec patch of a disk galaxy and resolving scales down to ?0.5 pc. Including an empirically motivated prescription for star formation from dense gas (n{sub H}>10{sup 5} cm{sup ?3}) at an efficiency of 2% per local free-fall time, we derive the amount of suppression of star formation by magnetic fields compared to the nonmagnetized case. We find GMC fragmentation, dense clump formation, and SFR can be significantly affected by the inclusion of magnetic fields, especially in our strongest investigated B-field case of 80 ?G. However, our chosen kiloparsec-scale region, extracted from a global galaxy simulation, happens to contain a starbursting cloud complex that is only modestly affected by these magnetic fields and likely requires internal star formation feedback to regulate its SFR.

  7. SU-C-16A-01: In Vivo Source Position Verification in High Dose Rate (HDR) Prostate Brachytherapy Using a Flat Panel Imager: Initial Clinical Experience

    SciTech Connect (OSTI)

    Franich, R; Smith, R; Millar, J; Haworth, A; Taylor, M; McDermott, L

    2014-06-15

    Purpose: We report our initial clinical experience with a novel position-sensitive source-tracking system based on a flat panel imager. The system has been trialled with 4 prostate HDR brachytherapy patients (8 treatment fractions) in this initial study. Methods: The flat panel imaging system was mounted under a customised carbon fibre couch top assembly (Figure 1). Three gold fiducial markers were implanted into the prostate of each patient at the time of catheter placement. X-ray dwell position markers were inserted into three catheters and a radiograph acquired to locate the implant relative to the imaging device. During treatment, as the HDR source dwells were delivered, images were acquired and processed to determine the position of the source in the patient. Source positions measured by the imaging device were compared to the treatment plan for verification of treatment delivery. Results: Measured dwell positions provided verification of relative dwell spacing within and between catheters, in the coronal plane. Measurements were typically within 2.0mm (0.2mm 3.3mm, s.d. 0.8mm) of the planned positions over 60 dwells (Figure 2). Discrimination between larger dwell intervals and catheter differentiation were clear. This confirms important delivery attributes such as correct transfer tube connection, source step size, relative catheter positions and therefore overall correct plan selection and delivery. The fiducial markers, visible on the radiograph, provided verification of treatment delivery to the correct anatomical location. The absolute position of the dwells was determined by comparing the measured dwell positions with the x-ray markers from the radiograph, validating the programmed treatment indexer length. The total impact on procedure time was less than 5 minutes. Conclusion: The novel, noninvasive HDR brachytherapy treatment verification system was used clinically with minor impact on workflow. The system allows verification of correct treatment delivery, free of most potential human related errors identified in ICRP 97. This research is supported by funding from the Australian Government Department of Health through Cancer Australia grant no. 616614.

  8. SU-E-T-371: Validation of Organ Doses Delivered During Craniospinal Irradiation with Helical Tomotherapy

    SciTech Connect (OSTI)

    Perez-Andujar, A; Chen, J; Garcia, A; Haas-Kogan, D

    2014-06-01

    Purpose: New techniques have been developed to deliver more conformal treatments to the craniospinal axis. One concern, however, is the widespread low dose delivered and implications for possible late effects. The purpose of this work is for the first time to validate the organ doses calculated by the treatment planning system (TPS), including out-of-field doses for a pediatric craniospinal treatment (CSI). Methods: A CSI plan prescribed to 23.4 Gy and a posterior fossa boost plan to 30.6 Gy (total dose 54.0 Gy) was developed for a pediatric anthropomorphic phantom representing a 13 yearold- child. For the CSI plan, the planning target volumes (PTV) consisted of the brain and spinal cord with 2 mm and 5 mm expansions, respectively. Organs at risk (OAR) were contoured and included in the plan optimization. The plans were delivered on a helical tomotherapy unit. Thermoluminescent dosimeters (TLDs) were used to measure the dose at 54 positions within the PTV and OARs. Results: For the CSI treatment, the mean percent difference between TPS dose calculations and measurements was 5% for the PTV and 10% for the OARs. For the boost, the average was 3% for the PTV. The percent difference for the OARs, which lie outside the field and received a small fraction of the prescription dose, varied from 15% to 200%. However in terms of absolute dose, the average difference between measurement and TPS per treatment Gy was 2 cGy/Gy and 3 mGy/Gy for the CSI and boost plans, respectively. Conclusion: There was good agreement between doses calculated by the TPS and measurements for the CSI treatment. Higher percent differences were observed for out-of-field doses in the boost plan, but absolute dose differences were very small compared to the prescription dose. These findings can help in the estimation of late effects after radiotherapy for pediatric patients.

  9. Ultralow dose computed tomography attenuation correction for pediatric PET CT using adaptive statistical iterative reconstruction

    SciTech Connect (OSTI)

    Brady, Samuel L.; Shulkin, Barry L.

    2015-02-15

    Purpose: To develop ultralow dose computed tomography (CT) attenuation correction (CTAC) acquisition protocols for pediatric positron emission tomography CT (PET CT). Methods: A GE Discovery 690 PET CT hybrid scanner was used to investigate the change to quantitative PET and CT measurements when operated at ultralow doses (1035 mA s). CT quantitation: noise, low-contrast resolution, and CT numbers for 11 tissue substitutes were analyzed in-phantom. CT quantitation was analyzed to a reduction of 90% volume computed tomography dose index (0.39/3.64; mGy) from baseline. To minimize noise infiltration, 100% adaptive statistical iterative reconstruction (ASiR) was used for CT reconstruction. PET images were reconstructed with the lower-dose CTAC iterations and analyzed for: maximum body weight standardized uptake value (SUV{sub bw}) of various diameter targets (range 837 mm), background uniformity, and spatial resolution. Radiation dose and CTAC noise magnitude were compared for 140 patient examinations (76 post-ASiR implementation) to determine relative dose reduction and noise control. Results: CT numbers were constant to within 10% from the nondose reduced CTAC image for 90% dose reduction. No change in SUV{sub bw}, background percent uniformity, or spatial resolution for PET images reconstructed with CTAC protocols was found down to 90% dose reduction. Patient population effective dose analysis demonstrated relative CTAC dose reductions between 62% and 86% (3.2/8.30.9/6.2). Noise magnitude in dose-reduced patient images increased but was not statistically different from predose-reduced patient images. Conclusions: Using ASiR allowed for aggressive reduction in CT dose with no change in PET reconstructed images while maintaining sufficient image quality for colocalization of hybrid CT anatomy and PET radioisotope uptake.

  10. 3rd Generation SCR System Using Solid Ammonia Storage and Direct Gas Dosing

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

    | Department of Energy rd Generation SCR System Using Solid Ammonia Storage and Direct Gas Dosing 3rd Generation SCR System Using Solid Ammonia Storage and Direct Gas Dosing SCR system provides direct ammonia gas dosing for optimal SCR performance with simplified and flexible exhaust layout. PDF icon deer12_johannessen.pdf More Documents & Publications Ammonia storage and delivery systems for NOx aftertreatment Safe and compact ammonia storage/delivery systems for SCR-DeNOX in automotive

  11. MCNP6 Dose Calculations for the Carousel in the LDRGIF (Technical...

    Office of Scientific and Technical Information (OSTI)

    Sponsoring Org: DOELANL Country of Publication: United States Language: English Subject: Nuclear Physics & Radiation Physics(73) mcnp, radiation transport, dose, polymers Word...

  12. Adjusting External Doses from the ORNL and Y-12 Facilities for...

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

    zero have monitoring data that demonstrate missing dose. A variable span smoother (Friedman, 1984) was applied to the data using the S-PLUS function, supersmu (Statistical...

  13. Columbia River Pathway Dosimetry Report, 1944-1992. Hanford Environmental Dose Reconstruction Project

    SciTech Connect (OSTI)

    Farris, W.T.; Napier, B.A.; Simpson, J.C.; Snyder, S.F.; Shipler, D.B.

    1994-04-01

    The purpose of the Hanford Environmental Dose Reconstruction (HEDR) Project is to estimate the radiation dose that individuals could have received as a result of radionuclide emissions since 1944 from the Hanford Site. One objective of the HEDR Project is to estimate doses to individuals who were exposed to the radionuclides released to the Columbia River (the river pathway). This report documents the last in a series of dose calculations conducted on the Columbia River pathway. The report summarizes the technical approach used to estimate radiation doses to three classes of representative individuals who may have used the Columbia River as a source of drinking water, food, or for recreational or occupational purposes. In addition, the report briefly explains the approaches used to estimate the radioactivity released to the river, the development of the parameters used to model the uptake and movement of radioactive materials in aquatic systems such as the Columbia River, and the method of calculating the Columbia River`s transport of radioactive materials. Potential Columbia River doses have been determined for representative individuals since the initiation of site activities in 1944. For this report, dose calculations were performed using conceptual models and computer codes developed for the purpose of estimating doses. All doses were estimated for representative individuals who share similar characteristics with segments of the general population.

  14. SU-E-T-279: Realization of Three-Dimensional Conformal Dose Planning in Prostate Brachytherapy

    SciTech Connect (OSTI)

    Li, Z; Jiang, S; Yang, Z; Bai, H; Zhang, X

    2014-06-01

    Purpose: Successful clinical treatment in prostate brachytherapy is largely dependent on the effectiveness of pre-surgery dose planning. Conventional dose planning method could hardly arrive at a satisfy result. In this abstract, a three-dimensional conformal localized dose planning method is put forward to ensure the accuracy and effectiveness of pre-implantation dose planning. Methods: Using Monte Carlo method, the pre-calculated 3-D dose map for single source is obtained. As for multiple seeds dose distribution, the maps are combined linearly to acquire the 3-D distribution. The 3-D dose distribution is exhibited in the form of isodose surface together with reconstructed 3-D organs group real-timely. Then it is possible to observe the dose exposure to target volume and normal tissues intuitively, thus achieving maximum dose irradiation to treatment target and minimum healthy tissues damage. In addition, the exfoliation display of different isodose surfaces can be realized applying multi-values contour extraction algorithm based on voxels. The needles could be displayed in the system by tracking the position of the implanted seeds in real time to conduct block research in optimizing insertion trajectory. Results: This study extends dose planning from two-dimensional to three-dimensional, realizing the three-dimensional conformal irradiation, which could eliminate the limitations of 2-D images and two-dimensional dose planning. A software platform is developed using VC++ and Visualization Toolkit (VTK) to perform dose planning. The 3-D model reconstruction time is within three seconds (on a Intel Core i5 PC). Block research could be conducted to avoid inaccurate insertion into sensitive organs or internal obstructions. Experiments on eight prostate cancer cases prove that this study could make the dose planning results more reasonable. Conclusion: The three-dimensional conformal dose planning method could improve the rationality of dose planning by safely reducing the large target margin and avoiding dose dead zones for prostate cancer treatment. 1) National Natural Science Foundation of People's Republic of China (No. 51175373); 2) New Century Educational Talents Plan of Chinese Education Ministry (NCET-10-0625); 3) Scientific and Technological Major Project, Tianjin (No. 12ZCDZSY10600)

  15. ACRO: Calculation of Organ Dose from Acute or Chronic Inhalation and Ingestion of

    Energy Science and Technology Software Center (OSTI)

    1982-02-01

    ACRO estimates the burden and dose to the organs or tissues as a result of inhalation or ingestion of radioactive materials.

  16. Radiological Control Technical Position, Regarding Use of Newer Dose Terms in the Occurrence Reporting and Processing System

    Broader source: Energy.gov [DOE]

    Technical Position Clarifying Dose Reporting in the Occurrence Reporting and Processing System - RCTP-09-03

  17. 2007 Wholesale Power Rate Case Initial Proposal : Wholesale Power Rate Development Study.

    SciTech Connect (OSTI)

    United States. Bonneville Power Administration.

    2007-11-01

    The Wholesale Power Rate Development Study (WPRDS) calculates BPA proposed rates based on information either developed in the WPRDS or supplied by the other studies that comprise the BPA rate proposal. All of these studies, and accompanying documentation, provide the details of computations and assumptions. In general, information about loads and resources is provided by the Load Resource Study (LRS), WP-07-E-BPA-01, and the LRS Documentation, WP-07-E-BPA-01A. Revenue requirements information, as well as the Planned Net Revenues for Risk (PNNR), is provided in the Revenue Requirement Study, WP-07-E-BPA-02, and its accompanying Revenue Requirement Study Documentation, WP-07-E-BPA-02A and WP-07-E-BPA-02B. The Market Price Forecast Study (MPFS), WP-07-E-BPA-03, and the MPFS Documentation, WP-07-E-BPA-03A, provide the WPRDS with information regarding seasonal and diurnal differentiation of energy rates, as well information regarding monthly market prices for Demand Rates. In addition, this study provides information for the pricing of unbundled power products. The Risk Analysis Study, WP-07-E-BPA-04, and the Risk Analysis Study Documentation, WP-07-E-BPA-04A, provide short-term balancing purchases as well as secondary energy sales and revenue. The Section 7(b)(2) Rate Test Study, WP-07-E-BPA-06, and the Section 7(b)(2) Rate Test Study Documentation, WP-07-E-BPA-06A, implement Section 7(b)(2) of the Northwest Power Act to ensure that BPA preference customers firm power rates applied to their general requirements are no higher than rates calculated using specific assumptions in the Northwest Power Act.

  18. Commercial production and distribution of fresh fruits and vegetables: A scoping study on the importance of produce pathways to dose. Hanford Environmental Dose Reconstruction Project

    SciTech Connect (OSTI)

    Marsh, T.L.; Anderson, D.M.; Farris, W.T.; Ikenberry, T.A.; Napier, B.A.; Wilfert, G.L.

    1992-09-01

    This letter report summarizes a scoping study that examined the potential importance of fresh fruit and vegetable pathways to dose. A simple production index was constructed with data collected from the Washington State Department of Agriculture (WSDA), the United States Bureau of the Census, and the United States Department of Agriculture (USDA). Hanford Environmental Dose Reconstruction (HEDR) Project staff from Battelle, Pacific Northwest Laboratories, in cooperation with members of the Technical Steering Panel (TSP), selected lettuce and spinach as the produce pathways most likely to impact dose. County agricultural reports published in 1956 provided historical descriptions of the predominant distribution patterns of fresh lettuce and spinach from production regions to local population centers. Pathway rankings and screening dose estimates were calculated for specific populations living in selected locations within the HEDR study area.

  19. Critical dose and toxicity index of organs at risk in radiotherapy: Analyzing the calculated effects of modified dose fractionation in nonsmall cell lung cancer

    SciTech Connect (OSTI)

    Pedicini, Piernicola; Strigari, Lidia; Benassi, Marcello; Caivano, Rocchina; Fiorentino, Alba; Nappi, Antonio; Salvatore, Marco; Storto, Giovanni

    2014-04-01

    To increase the efficacy of radiotherapy for nonsmall cell lung cancer (NSCLC), many schemes of dose fractionation were assessed by a new toxicity index (I), which allows one to choose the fractionation schedules that produce less toxic treatments. Thirty-two patients affected by non resectable NSCLC were treated by standard 3-dimensional conformal radiotherapy (3DCRT) with a strategy of limited treated volume. Computed tomography datasets were employed to re plan by simultaneous integrated boost intensity-modulated radiotherapy (IMRT). The dose distributions from plans were used to test various schemes of dose fractionation, in 3DCRT as well as in IMRT, by transforming the dose-volume histogram (DVH) into a biological equivalent DVH (BDVH) and by varying the overall treatment time. The BDVHs were obtained through the toxicity index, which was defined for each of the organs at risk (OAR) by a linear quadratic model keeping an equivalent radiobiological effect on the target volume. The less toxic fractionation consisted in a severe/moderate hyper fractionation for the volume including the primary tumor and lymph nodes, followed by a hypofractionation for the reduced volume of the primary tumor. The 3DCRT and IMRT resulted, respectively, in 4.7% and 4.3% of dose sparing for the spinal cord, without significant changes for the combined-lungs toxicity (p < 0.001). Schedules with reduced overall treatment time (accelerated fractionations) led to a 12.5% dose sparing for the spinal cord (7.5% in IMRT), 8.3% dose sparing for V{sub 20} in the combined lungs (5.5% in IMRT), and also significant dose sparing for all the other OARs (p < 0.001). The toxicity index allows to choose fractionation schedules with reduced toxicity for all the OARs and equivalent radiobiological effect for the tumor in 3DCRT, as well as in IMRT, treatments of NSCLC.

  20. Liability aspects of home energy-rating systems

    SciTech Connect (OSTI)

    Hendrickson, P.L.

    1983-10-01

    Liability aspects of home energy rating systems are discussed. An introduction to the rating system concept, including types of rating systems, implementation efforts to date, and possible groups to conduct ratings, is also included. The home energy rating system concept involves the periodic rating of the energy efficiency of residential buildings. The rating can provide a relative indication of a home's energy efficiency and also a quantitative estimate of consumption, fuel cost, or both. Primary attention is given to liability issues associated with developing and performing ratings. Secondary attention is given to possible liability associated with misuse of a rating once it has been performed.

  1. Commercial Building Asset Rating Program | Department of Energy

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

    Asset Rating Program Commercial Building Asset Rating Program Slides from a Commercial Building Initiative webinar outlining the Commercial Building Asset Rating Program on August 23, 2011. PDF icon asset_rating.pdf More Documents & Publications Commercial Building Energy Asset Score: 2013 Pilot Overview Commercial Building Energy Asset Rating Workshop Commercial Building Energy Asset Score: Pilot Findings and Program Update

  2. Commercial Building Energy Asset Rating Workshop | Department of Energy

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

    Rating Workshop Commercial Building Energy Asset Rating Workshop DOE commercial building energy asset rating program information presented to stakeholders at the workshop held in Washington, DC, December 2011 PDF icon asset_rating_dc_workshop_handout_20111214.pdf More Documents & Publications Commercial Building Asset Rating Program Commercial Building Energy Asset Score: Pilot Findings and Program Update

  3. 1, THIS CONIRACT IS A RATED ORDER

    Office of Environmental Management (EM)

    ,/OTHER 1, THIS CONIRACT IS A RATED ORDER UNDER DPAS 115 CFR 350} 3, EFFECTIVE DATE 12/22/2009 10, SUBMIT INVOICES ffî',1:ïïiï:3'1".ïäfuî"ñ'*" I ntinued AWARD/CONTRACT 2. CONTRACT (Proc. lnst. /denf.) NO DE-Cr0000004 - ISSUED BY -|{CBC * Springdale U. S. Department of Energy EM Consolidated Business Center 175 Tri-County Park\^Iay Springdale OH 45246-3222 7. NAME AND ADDRESS OF CONTRACTOR (No., Street, C¡ty, Country, State and ZIP Çode) V,IASTREN - ENERGX MISSION

  4. Systematic muon capture rates in PQRPA

    SciTech Connect (OSTI)

    Samana, A. R.; Sande, D.; Krmpoti?, F.

    2015-05-15

    In this work we performed a systematic study of the inclusive muon capture rates for several nuclei with A < 60 using the Projected Random Quasi-particle Phase Approximation (PQRPA) as nuclear model, because it is the only RPA model that treats the Pauli Principle correctly. We reckon that the comparison between theory and data for the inclusive muon capture is not a fully satisfactory test on the nuclear model that is used. The exclusive muon transitions are more robust for such a purpose.

  5. Estimated recharge rates at the Hanford Site

    SciTech Connect (OSTI)

    Fayer, M.J.; Walters, T.B.

    1995-02-01

    The Ground-Water Surveillance Project monitors the distribution of contaminants in ground water at the Hanford Site for the U.S. Department of Energy. A subtask called {open_quotes}Water Budget at Hanford{close_quotes} was initiated in FY 1994. The objective of this subtask was to produce a defensible map of estimated recharge rates across the Hanford Site. Methods that have been used to estimate recharge rates at the Hanford Site include measurements (of drainage, water contents, and tracers) and computer modeling. For the simulations of 12 soil-vegetation combinations, the annual rates varied from 0.05 mm/yr for the Ephrata sandy loam with bunchgrass to 85.2 mm/yr for the same soil without vegetation. Water content data from the Grass Site in the 300 Area indicated that annual rates varied from 3.0 to 143.5 mm/yr during an 8-year period. The annual volume of estimated recharge was calculated to be 8.47 {times} 10{sup 9} L for the potential future Hanford Site (i.e., the portion of the current Site bounded by Highway 240 and the Columbia River). This total volume is similar to earlier estimates of natural recharge and is 2 to 10x higher than estimates of runoff and ground-water flow from higher elevations. Not only is the volume of natural recharge significant in comparison to other ground-water inputs, the distribution of estimated recharge is highly skewed to the disturbed sandy soils (i.e., the 200 Areas, where most contaminants originate). The lack of good estimates of the means and variances of the supporting data (i.e., the soil map, the vegetation/land use map, the model parameters) translates into large uncertainties in the recharge estimates. When combined, the significant quantity of estimated recharge, its high sensitivity to disturbance, and the unquantified uncertainty of the data and model parameters suggest that the defensibility of the recharge estimates should be improved.

  6. SU-E-T-183: Feasibility of Extreme Dose Escalation for Glioblastoma Multiforme Using 4? Radiotherapy

    SciTech Connect (OSTI)

    Nguyen, D; Rwigema, J; Yu, V; Kaprealian, T; Kupelian, P; Selch, M; Low, D; Sheng, K

    2014-06-01

    Purpose: GBM recurrence primarily occurs inside or near the high-dose radiation field of original tumor site requiring greater than 100 Gy to significantly improve local control. We utilize 4? non-coplanar radiotherapy to test the feasibility of planning target volume (PTV) margin expansions or extreme dose escalations without incurring additional radiation toxicities. Methods: 11 GBM patients treated with VMAT to a prescription dose of 59.4 Gy or 60 Gy were replanned with 4?. Original VMAT plans were created with 2 to 4 coplanar or non-coplanar arcs using 3 mm hi-res MLC. The 4? optimization, using 5 mm MLC, selected and inverse optimized 30 beams from a candidate pool of 1162 beams evenly distributed through 4? steradians. 4? plans were first compared to clinical plans using the same prescription dose. Two more studies were then performed to respectively escalate the GTV and PTV doses to 100 Gy, followed by a fourth plan expanding the PTV by 5 mm and maintaining the prescription dose. Results: The standard 4? plan significantly reduced (p<0.01) max and mean doses to critical structures by a range of 47.098.4% and 61.099.2%, respectively. The high dose PTV/high dose GTV/expanded PTV studies showed a reduction (p<0.05) or unchanged* (p>0.05) maximum dose of 72.1%/86.7%/77.1% (chiasm), 7.2%*/27.7%*/30.7% (brainstem), 39.8%*/84.2%/51.9%* (spinal cord), 69.0%/87.0%/66.9% (L eye), 76.2%/88.1%/84.1% (R eye), 95.0%/98.6%/97.5% (L lens), 93.9%/98.8%/97.6% (R lens), 74.3%/88.5%/72.4% (L optical nerve), 80.4%/91.3%/75.7% (R optical nerve), 64.8%/84.2%/44.9%* (L cochlea), and 85.2%/93.0%/78.0% (R cochlea), respectively. V30 and V36 for both brain and (brain - PTV) were reduced for all cases except the high dose PTV plan. PTV dose coverage increased for all 4? plans. Conclusion: Extreme dose escalation or further margin expansion is achievable using 4?, maintaining or reducing OAR doses. This study indicates that clinical trials employing 4? delivery using prescription doses up to 100 Gy are feasible. Funding support partially contributed by Varian.

  7. Influence of polarization and a source model for dose calculation in MRT

    SciTech Connect (OSTI)

    Bartzsch, Stefan Oelfke, Uwe; Lerch, Michael; Petasecca, Marco; Bruer-Krisch, Elke

    2014-04-15

    Purpose: Microbeam Radiation Therapy (MRT), an alternative preclinical treatment strategy using spatially modulated synchrotron radiation on a micrometer scale, has the great potential to cure malignant tumors (e.g., brain tumors) while having low side effects on normal tissue. Dose measurement and calculation in MRT is challenging because of the spatial accuracy required and the arising high dose differences. Dose calculation with Monte Carlo simulations is time consuming and their accuracy is still a matter of debate. In particular, the influence of photon polarization has been discussed in the literature. Moreover, it is controversial whether a complete knowledge of phase space trajectories, i.e., the simulation of the machine from the wiggler to the collimator, is necessary in order to accurately calculate the dose. Methods: With Monte Carlo simulations in the Geant4 toolkit, the authors investigate the influence of polarization on the dose distribution and the therapeutically important peak to valley dose ratios (PVDRs). Furthermore, the authors analyze in detail phase space information provided byMartnez-Rovira et al. [Development and commissioning of a Monte Carlo photon model for the forthcoming clinical trials in microbeam radiation therapy, Med. Phys. 39(1), 119131 (2012)] and examine its influence on peak and valley doses. A simple source model is developed using parallel beams and its applicability is shown in a semiadjoint Monte Carlo simulation. Results are compared to measurements and previously published data. Results: Polarization has a significant influence on the scattered dose outside the microbeam field. In the radiation field, however, dose and PVDRs deduced from calculations without polarization and with polarization differ by less than 3%. The authors show that the key consequences from the phase space information for dose calculations are inhomogeneous primary photon flux, partial absorption due to inclined beam incidence outside the field center, increased beam width and center to center distance due to the beam propagation from the collimator to the phantom surface and imperfect absorption in the absorber material of the Multislit Collimator. These corrections have an effect of approximately 10% on the valley dose and suffice to describe doses in MRT within the measurement uncertainties of currently available dosimetry techniques. Conclusions: The source for the first clinical pet trials in MRT is characterized with respect to its phase space and the photon polarization. The results suggest the use of a presented simplified phase space model in dose calculations and hence pave the way for alternative and fast dose calculation algorithms. They also show that the polarization is of minor importance for the clinical important peak and valley doses inside the microbeam field.

  8. Static jaw collimation settings to minimize radiation dose to normal brain tissue during stereotactic radiosurgery

    SciTech Connect (OSTI)

    Han, Eun Young; Zhang Xin; Yan Yulong; Sharma, Sunil; Penagaricano, Jose; Moros, Eduardo; Corry, Peter

    2012-01-01

    At University of Arkansas for Medical Sciences (UAMS) intracranial stereotactic radiosurgery (SRS) is performed by using a linear accelerator with an add-on micromultileaf collimator (mMLC). In our clinical setting, static jaws are automatically adapted to the furthest edge of the mMLC-defined segments with 2-mm (X jaw) and 5-mm (Y jaw) margin and the same jaw values are applied for all beam angles in the treatment planning system. This additional field gap between the static jaws and the mMLC allows additional radiation dose to normal brain tissue. Because a radiosurgery procedure consists of a single high dose to the planning target volume (PTV), reduction of unnecessary dose to normal brain tissue near the PTV is important, particularly for pediatric patients whose brains are still developing or when a critical organ, such as the optic chiasm, is near the PTV. The purpose of this study was to minimize dose to normal brain tissue by allowing minimal static jaw margin around the mMLC-defined fields and different static jaw values for each beam angle or arc. Dose output factors were measured with various static jaw margins and the results were compared with calculated doses in the treatment planning system. Ten patient plans were randomly selected and recalculated with zero static jaw margins without changing other parameters. Changes of PTV coverage, mean dose to predefined normal brain tissue volume adjacent to PTV, and monitor units were compared. It was found that the dose output percentage difference varied from 4.9-1.3% for the maximum static jaw opening vs. static jaw with zero margins. The mean dose to normal brain tissue at risk adjacent to the PTV was reduced by an average of 1.9%, with negligible PTV coverage loss. This dose reduction strategy may be meaningful in terms of late effects of radiation, particularly in pediatric patients. This study generated clinical knowledge and tools to consistently minimize dose to normal brain tissue.

  9. Randomized Noninferiority Trial of Reduced High-Dose Volume Versus Standard Volume Radiation Therapy for Muscle-Invasive Bladder Cancer: Results of the BC2001 Trial (CRUK/01/004)

    SciTech Connect (OSTI)

    Huddart, Robert A.; Hall, Emma; Hussain, Syed A.; Jenkins, Peter; Rawlings, Christine; Tremlett, Jean; Crundwell, Malcolm; Adab, Fawzi A.; Sheehan, Denise; Syndikus, Isabel; Hendron, Carey; Lewis, Rebecca; Waters, Rachel; James, Nicholas D.

    2013-10-01

    Purpose: To test whether reducing radiation dose to uninvolved bladder while maintaining dose to the tumor would reduce side effects without impairing local control in the treatment of muscle-invasive bladder cancer. Methods and Materials: In this phase III multicenter trial, 219 patients were randomized to standard whole-bladder radiation therapy (sRT) or reduced high-dose volume radiation therapy (RHDVRT) that aimed to deliver full radiation dose to the tumor and 80% of maximum dose to the uninvolved bladder. Participants were also randomly assigned to receive radiation therapy alone or radiation therapy plus chemotherapy in a partial 2 2 factorial design. The primary endpoints for the radiation therapy volume comparison were late toxicity and time to locoregional recurrence (with a noninferiority margin of 10% at 2 years). Results: Overall incidence of late toxicity was less than predicted, with a cumulative 2-year Radiation Therapy Oncology Group grade 3/4 toxicity rate of 13% (95% confidence interval 8%, 20%) and no statistically significant differences between groups. The difference in 2-year locoregional recurrence free rate (RHDVRT ? sRT) was 6.4% (95% confidence interval ?7.3%, 16.8%) under an intention to treat analysis and 2.6% (?12.8%, 14.6%) in the per-protocol population. Conclusions: In this study RHDVRT did not result in a statistically significant reduction in late side effects compared with sRT, and noninferiority of locoregional control could not be concluded formally. However, overall low rates of clinically significant toxicity combined with low rates of invasive bladder cancer relapse confirm that (chemo)radiation therapy is a valid option for the treatment of muscle-invasive bladder cancer.

  10. Directional recoil rates for WIMP direct detection

    SciTech Connect (OSTI)

    Alenazi, Moqbil S.; Gondolo, Paolo [Department of Physics, University of Utah, 115 S 1400 E Rm 201, Salt Lake City, Utah 84112-0830 (United States)

    2008-02-15

    New techniques for the laboratory direct detection of dark matter weakly interacting massive particles (WIMPs) are sensitive to the recoil direction of the struck nuclei. We compute and compare the directional recoil rates dR/dcos{theta} (where {theta} is the angle measured from a reference direction in the sky) for several WIMP velocity distributions including the standard dark halo and anisotropic models such as Sikivie's late-infall halo model and logarithmic-ellipsoidal models. Since some detectors may be unable to distinguish the beginning of the recoil track from its end (lack of head-tail discrimination), we introduce a folded directional recoil rate dR/d|cos{theta}|, where |cos{theta}| does not distinguish the head from the tail of the track. We compute the CS{sub 2} and CF{sub 4} exposures required to distinguish a signal from an isotropic background noise, and find that dR/d|cos{theta}| is effective for the standard dark halo and some but not all anisotropic models.

  11. TIME-VARYING DYNAMICAL STAR FORMATION RATE

    SciTech Connect (OSTI)

    Lee, Eve J.; Chang, Philip; Murray, Norman

    2015-02-10

    We present numerical evidence of dynamic star formation in which the accreted stellar mass grows superlinearly with time, roughly as t {sup 2}. We perform simulations of star formation in self-gravitating hydrodynamic and magnetohydrodynamic turbulence that is continuously driven. By turning the self-gravity of the gas in the simulations on or off, we demonstrate that self-gravity is the dominant physical effect setting the mass accretion rate at early times before feedback effects take over, contrary to theories of turbulence-regulated star formation. We find that gravitational collapse steepens the density profile around stars, generating the power-law tail on what is otherwise a lognormal density probability distribution function. Furthermore, we find turbulent velocity profiles to flatten inside collapsing regions, altering the size-line width relation. This local flattening reflects enhancements of turbulent velocity on small scales, as verified by changes to the velocity power spectra. Our results indicate that gas self-gravity dynamically alters both density and velocity structures in clouds, giving rise to a time-varying star formation rate. We find that a substantial fraction of the gas that forms stars arrives via low-density flows, as opposed to accreting through high-density filaments.

  12. Create New fictional Rate | OpenEI Community

    Open Energy Info (EERE)

    Create New fictional Rate Home > Groups > Utility Rate Hi - if it possible to create a custom rate format for a fictional utility? I am working on some modeling and I think this...

  13. electricity rates for military bases | OpenEI Community

    Open Energy Info (EERE)

    electricity rates for military bases Home > Groups > Utility Rate Hi, I was hoping to find rates for military bases, but have been unable to find anything. Are they just charged as...

  14. NC-1-B Wholesale Power Rate Schedule | Department of Energy

    Energy Savers [EERE]

    NC-1-B Wholesale Power Rate Schedule NC-1-B Wholesale Power Rate Schedule Area: Virginia PowerCP&L System: Kerr-Philpott This rate schedule shall be available to public bodies and...

  15. CTV-1-H Wholesale Power Rate Schedule | Department of Energy

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

    TVA. Document Available for Download PDF icon CTV-1-H Rate Schedule More Documents & Publications CTVI-1-A Wholesale Power Rate Schedule CEK-1-H Wholesale Power Rate Schedule CM

  16. CBR-1-H Wholesale Power Rate Schedule | Department of Energy

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

    CBR-1-H Wholesale Power Rate Schedule CBR-1-H Wholesale Power Rate Schedule Area: Big Rivers and Henderson, KY System: CU This rate schedule shall be available to Big Rivers ...

  17. Credit-Based Interest Rate Spread for Title XVII

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

    to unhedged market-based pricing risk; and * Are able to provide a rating from a nationally recognized third party credit rating agency that falls within the range of ratings ...

  18. Utility Rate - Q & A | OpenEI Community

    Open Energy Info (EERE)

    Utility Rate - Q & A Home > Utility Rate Content Group Activity By term Q & A Feeds Question Post date Answers Why don't the rates match my price to compare 21 Dec 2015 - 15:24 2...

  19. CSI-1-H Wholesale Power Rate Schedule | Department of Energy

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

    CSI-1-H Wholesale Power Rate Schedule CSI-1-H Wholesale Power Rate Schedule Area: Southern Illinois System: CU This rate schedule shall be available to Southern Illinois Power...

  20. Regional Dialogue Guidebook: Background on Products, Rates, and...

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

    Block Product 4. Renewable Energy Certificates (REC Program) Part 2: Tiered Rate Methodology (TRM) A. Tier 1 Rate Design B. Tier 2 Rate Alternatives 1. Load-Growth Service 2....

  1. Microsoft Word - News Release -- Rating Agencies affirms BPA...

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

    bond sale will save BPA rate payers millions of dollars Portland, Ore. - The three major credit rating agencies affirmed the ratings on BPA- backed debt last week, paving the way...

  2. Widget:UtilityRateEntryHelper | Open Energy Information

    Open Energy Info (EERE)

    UtilityRateEntryHelper Jump to: navigation, search This widget displays the utility rate database form. For example: Widget:UtilityRateEntryHelper|urdbContextview|urdbPageTitle...

  3. Widget:UtilityRateEntryHelperVideo | Open Energy Information

    Open Energy Info (EERE)

    UtilityRateEntryHelperVideo Jump to: navigation, search This widget displays the utility rate database form helper video. For example: Widget:UtilityRateEntryHelperVideo...

  4. Widget:UtilityRateEntryHelperTable | Open Energy Information

    Open Energy Info (EERE)

    UtilityRateEntryHelperTable Jump to: navigation, search This widget displays the utility rate database form. For example: Widget:UtilityRateEntryHelperTable Retrieved from...

  5. JW-2-F Wholesale Power Rate Schedule | Department of Energy

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

    2-F Wholesale Power Rate Schedule JW-2-F Wholesale Power Rate Schedule Area: Florida Power Corporation System: Jim Woodruff This rate schedule shall be available to the Florida ...

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

    SciTech Connect (OSTI)

    Baker, D.A. )

    1990-08-01

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

  7. Evaluation of a new commercial Monte Carlo dose calculation algorithm for electron beams

    SciTech Connect (OSTI)

    Vandervoort, Eric J. Cygler, Joanna E.; The Faculty of Medicine, The University of Ottawa, Ottawa, Ontario K1H 8M5; Department of Physics, Carleton University, Ottawa, Ontario K1S 5B6 ; Tchistiakova, Ekaterina; Department of Medical Biophysics, University of Toronto, Ontario M5G 2M9; Heart and Stroke Foundation Centre for Stroke Recovery, Sunnybrook Research Institute, University of Toronto, Ontario M4N 3M5 ; La Russa, Daniel J.; The Faculty of Medicine, The University of Ottawa, Ottawa, Ontario K1H 8M5

    2014-02-15

    Purpose: In this report the authors present the validation of a Monte Carlo dose calculation algorithm (XiO EMC from Elekta Software) for electron beams. Methods: Calculated and measured dose distributions were compared for homogeneous water phantoms and for a 3D heterogeneous phantom meant to approximate the geometry of a trachea and spine. Comparisons of measurements and calculated data were performed using 2D and 3D gamma index dose comparison metrics. Results: Measured outputs agree with calculated values within estimated uncertainties for standard and extended SSDs for open applicators, and for cutouts, with the exception of the 17 MeV electron beam at extended SSD for cutout sizes smaller than 5 5 cm{sup 2}. Good agreement was obtained between calculated and experimental depth dose curves and dose profiles (minimum number of measurements that pass a 2%/2 mm agreement 2D gamma index criteria for any applicator or energy was 97%). Dose calculations in a heterogeneous phantom agree with radiochromic film measurements (>98% of pixels pass a 3 dimensional 3%/2 mm ?-criteria) provided that the steep dose gradient in the depth direction is considered. Conclusions: Clinically acceptable agreement (at the 2%/2 mm level) between the measurements and calculated data for measurements in water are obtained for this dose calculation algorithm. Radiochromic film is a useful tool to evaluate the accuracy of electron MC treatment planning systems in heterogeneous media.

  8. Automated treatment planning for a dedicated multi-source intra-cranial radiosurgery treatment unit accounting for overlapping structures and dose homogeneity

    SciTech Connect (OSTI)

    Ghobadi, Kimia; Ghaffari, Hamid R.; Aleman, Dionne M.; Institute of Health Policy, Management and Evaluation, University of Toronto, Ontario M5T 3M6; Techna Institute, University Health Network, Ontario M5G 1P5 ; Jaffray, David A.; Department of Radiation Oncology, University of Toronto, Ontario M5S 3E2; Department of Medical Biophysics, University of Toronto, Ontario M5G 2M9; Institute of Biomaterial and Biomedical Engineering, University of Toronto, Ontario M5S 2J7; Techna Institute, University Health Network, Ontario M5G 1P5; Ontario Cancer Institute, Ontario M5G 0A3 ; Ruschin, Mark; Department of Radiation Oncology, University of Toronto, Toronto, Ontario M5S 3E2

    2013-09-15

    Purpose: The purpose of this work is to advance the two-step approach for Gamma Knife{sup } Perfexion (PFX) optimization to account for dose homogeneity and overlap between the planning target volume (PTV) and organs-at-risk (OARs).Methods: In the first step, a geometry-based algorithm is used to quickly select isocentre locations while explicitly accounting for PTV-OARs overlaps. In this approach, the PTV is divided into subvolumes based on the PTV-OARs overlaps and the distance of voxels to the overlaps. Only a few isocentres are selected in the overlap volume, and a higher number of isocentres are carefully selected among voxels that are immediately close to the overlap volume. In the second step, a convex optimization is solved to find the optimal combination of collimator sizes and their radiation duration for each isocentre location.Results: This two-step approach is tested on seven clinical cases (comprising 11 targets) for which the authors assess coverage, OARs dose, and homogeneity index and relate these parameters to the overlap fraction for each case. In terms of coverage, the mean V{sub 99} for the gross target volume (GTV) was 99.8% while the V{sub 95} for the PTV averaged at 94.6%, thus satisfying the clinical objectives of 99% for GTV and 95% for PTV, respectively. The mean relative dose to the brainstem was 87.7% of the prescription dose (with maximum 108%), while on average, 11.3% of the PTV overlapped with the brainstem. The mean beam-on time per fraction per dose was 8.6 min with calibration dose rate of 3.5 Gy/min, and the computational time averaged at 205 min. Compared with previous work involving single-fraction radiosurgery, the resulting plans were more homogeneous with average homogeneity index of 1.18 compared to 1.47.Conclusions: PFX treatment plans with homogeneous dose distribution can be achieved by inverse planning using geometric isocentre selection and mathematical modeling and optimization techniques. The quality of the obtained treatment plans are clinically satisfactory while the homogeneity index is improved compared to conventional PFX plans.

  9. SU-E-I-28: Evaluating the Organ Dose From Computed Tomography Using Monte Carlo Calculations

    SciTech Connect (OSTI)

    Ono, T; Araki, F

    2014-06-01

    Purpose: To evaluate organ doses from computed tomography (CT) using Monte Carlo (MC) calculations. Methods: A Philips Brilliance CT scanner (64 slice) was simulated using the GMctdospp (IMPS, Germany) based on the EGSnrc user code. The X-ray spectra and a bowtie filter for MC simulations were determined to coincide with measurements of half-value layer (HVL) and off-center ratio (OCR) profile in air. The MC dose was calibrated from absorbed dose measurements using a Farmer chamber and a cylindrical water phantom. The dose distribution from CT was calculated using patient CT images and organ doses were evaluated from dose volume histograms. Results: The HVLs of Al at 80, 100, and 120 kV were 6.3, 7.7, and 8.7 mm, respectively. The calculated HVLs agreed with measurements within 0.3%. The calculated and measured OCR profiles agreed within 3%. For adult head scans (CTDIvol) =51.4 mGy), mean doses for brain stem, eye, and eye lens were 23.2, 34.2, and 37.6 mGy, respectively. For pediatric head scans (CTDIvol =35.6 mGy), mean doses for brain stem, eye, and eye lens were 19.3, 24.5, and 26.8 mGy, respectively. For adult chest scans (CTDIvol=19.0 mGy), mean doses for lung, heart, and spinal cord were 21.1, 22.0, and 15.5 mGy, respectively. For adult abdominal scans (CTDIvol=14.4 mGy), the mean doses for kidney, liver, pancreas, spleen, and spinal cord were 17.4, 16.5, 16.8, 16.8, and 13.1 mGy, respectively. For pediatric abdominal scans (CTDIvol=6.76 mGy), mean doses for kidney, liver, pancreas, spleen, and spinal cord were 8.24, 8.90, 8.17, 8.31, and 6.73 mGy, respectively. In head scan, organ doses were considerably different from CTDIvol values. Conclusion: MC dose distributions calculated by using patient CT images are useful to evaluate organ doses absorbed to individual patients.

  10. California Federal Facilities: Rate-Responsive Buidling Operating...

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

    Facilities: Rate-Responsive Buidling Operating for Deeper Cost and Energy Savings California Federal Facilities: Rate-Responsive Buidling Operating for Deeper Cost and Energy...

  11. Auto/Steel Partnership: Fatigue of AHSS Strain Rate Characterization...

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

    Fatigue of AHSS Strain Rate Characterization AutoSteel Partnership: Fatigue of AHSS ... More Documents & Publications AutoSteel Partnership: AHSS Stamping, Strain Rate ...

  12. Auto/Steel Partnership: AHSS Stamping, Strain Rate Characterization...

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

    AHSS Stamping, Strain Rate Characterization, Sheet Steel Fatigue, AHSS Joining AutoSteel ... More Documents & Publications AutoSteel Partnership: Fatigue of AHSS Strain Rate ...

  13. Control Strategies for Centrifugal Pumps with Variable Flow Rate...

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

    Control Strategies for Centrifugal Pumps with Variable Flow Rate Requirements Control Strategies for Centrifugal Pumps with Variable Flow Rate Requirements This tip sheet discusses...

  14. DOE Commercial Building Energy Asset Rating Program Focus Groups...

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

    More Documents & Publications Commercial Building Energy Asset Rating Workshop A Common Definition for Zero Energy Buildings Building Energy Rating and Disclosure Policies

  15. Flow rate--pressure drop relation for deformable shallow microfluidic...

    Office of Scientific and Technical Information (OSTI)

    Flow rate--pressure drop relation for deformable shallow microfluidic channels Citation Details In-Document Search Title: Flow rate--pressure drop relation for deformable shallow...

  16. Neutrino Coherent Scattering Rates at Direct Dark Matter Detectors...

    Office of Scientific and Technical Information (OSTI)

    Neutrino Coherent Scattering Rates at Direct Dark Matter Detectors Citation Details In-Document Search Title: Neutrino Coherent Scattering Rates at Direct Dark Matter Detectors ...

  17. Does Water Content or Flow Rate Control Colloid Transport in...

    Office of Scientific and Technical Information (OSTI)

    Does Water Content or Flow Rate Control Colloid Transport in Unsaturated Porous Media? Citation Details In-Document Search Title: Does Water Content or Flow Rate Control Colloid ...

  18. AP-3-B Wholesale Power Rate Schedule | Department of Energy

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

    3-B Wholesale Power Rate Schedule AP-3-B Wholesale Power Rate Schedule Area: American ... American Electric Power Service Corporation (hereinafter called the Company), PJM ...

  19. AP-1-B Wholesale Power Rate Schedule | Department of Energy

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

    1-B Wholesale Power Rate Schedule AP-1-B Wholesale Power Rate Schedule Area: American ... American Electric Power Service Corporation (hereinafter called the Company), the ...

  20. AP-2-B Wholesale Power Rate Schedule | Department of Energy

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

    2-B Wholesale Power Rate Schedule AP-2-B Wholesale Power Rate Schedule Area: American ... American Electric Power Service Corporation (hereinafter called the Company), the ...

  1. AP-4-B Wholesale Power Rate Schedule | Department of Energy

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

    4-B Wholesale Power Rate Schedule AP-4-B Wholesale Power Rate Schedule Area: American ... of American Electric Power Service Corporation (hereinafter called the Company) and ...

  2. Reaction Rates and Catalysts in Ethanol Production (1 Activity...

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

    Reaction Rates and Catalysts in Ethanol Production (1 Activity) Reaction Rates and Catalysts in Ethanol Production (1 Activity) Below is information about the student activity...

  3. FITCH RATES ENERGY NORTHWEST, WA'S ELECTRIC REV RFDG BONDS 'AA...

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

    debt (4.1 billion). KEY RATING DRIVERS BONNEVILLE'S OBLIGATION SECURES BONDS: The rating on the Energy Northwest bonds reflects the credit quality of Bonneville and its...

  4. Guidance on Utility Rate Estimations and Weather Normalization...

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

    Utility Rate Estimations and Weather Normalization in an ESPC Guidance on Utility Rate Estimations and Weather Normalization in an ESPC Document explains how to use estimated...

  5. Estimation of 1945 to 1957 food consumption. Hanford Environmental Dose Reconstruction Project

    SciTech Connect (OSTI)

    Anderson, D.M.; Bates, D.J.; Marsh, T.L.

    1993-07-01

    This report details the methods used and the results of the study on the estimated historic levels of food consumption by individuals in the Hanford Environmental Dose Reconstruction (HEDR) study area from 1945--1957. This period includes the time of highest releases from Hanford and is the period for which data are being collected in the Hanford Thyroid Disease Study. These estimates provide the food-consumption inputs for the HEDR database of individual diets. This database will be an input file in the Hanford Environmental Dose Reconstruction Integrated Code (HEDRIC) computer model that will be used to calculate the radiation dose. The report focuses on fresh milk, eggs, lettuce, and spinach. These foods were chosen because they have been found to be significant contributors to radiation dose based on the Technical Steering Panel dose decision level.

  6. Extremum seeking with bounded update rates

    SciTech Connect (OSTI)

    Scheinker, Alexander; Krsti?, Miroslav

    2013-11-16

    In this work, we present a form of extremum seeking (ES) in which the unknown function being minimized enters the systems dynamics as the argument of a cosine or sine term, thereby guaranteeing known bounds on update rates and control efforts. We present general n-dimensional optimization and stabilization results as well as 2D vehicle control, with bounded velocity and control efforts. For application to autonomous vehicles, tracking a source in a GPS denied environment with unknown orientation, this ES approach allows for smooth heading angle actuation, with constant velocity, and in application to a unicycle-type vehicle results in control ability as if the vehicle is fully actuated. Our stability analysis is made possible by the classic results of Kurzweil, Jarnik, Sussmann, and Liu, regarding systems with highly oscillatory terms. In our stability analysis, we combine the averaging results with a semi-global practical stability result under small parametric perturbations developed by Moreau and Aeyels.

  7. Adjustable flow rate controller for polymer solutions

    DOE Patents [OSTI]

    Jackson, Kenneth M. (Bartlesville, OK)

    1981-01-01

    An adjustable device for controlling the flow rate of polymer solutions which results in only little shearing of the polymer molecules, said device comprising an inlet manifold, an outlet manifold, a plurality of tubes capable of providing communication between said inlet and outlet manifolds, said tubes each having an internal diameter that is smaller than that of the inlet manifold and large enough to insure that viscosity of the polymer solution passing through each said tube will not be reduced more than about 25 percent, and a valve associated with each tube, said valve being capable of opening or closing communication in that tube between the inlet and outlet manifolds, each said valve when fully open having a diameter that is substantially at least as great as that of the tube with which it is associated.

  8. Fast radiographic film calibration procedure for helical tomotherapy intensity modulated radiation therapy dose verification

    SciTech Connect (OSTI)

    Yan Yulong; Papanikolaou, Nikos; Weng Xuejun; Penagaricano, Jose; Ratanatharathorn, Vaneerat

    2005-06-15

    Film dosimetry offers an advantageous in-phantom planar dose verification tool in terms of spatial resolution and ease of handling for quality assurance (QA) of intensity modulated radiation therapy (IMRT) plans. A critical step in the success of such a technique is that the film calibration be appropriately conducted. This paper presents a fast and efficient film calibration method for a helical tomotherapy unit using a single sheet of film. Considering the unique un-flattened cone shaped profile from a helical tomotherapy beam, a custom leaf control file (sinogram) was created, to produce a valley shaped intensity pattern. There are eleven intensity steps in the valley pattern, representing varying dose values from 38 to 265 cGy. This dose range covers the most commonly prescribed doses in fractionated IMRT treatments. An ion chamber in a solid water phantom was used to measure the dose in each of the eleven steps. For daily film calibration the whole procedure, including film exposure, processing, digitization and analysis, can be completed within 15 min, making it practical to use this technique routinely. This method is applicable to film calibration on a helical tomotherapy unit and is particularly useful in IMRT planar dose verification due to its efficiency and reproducibility. In this work, we characterized the dose response of the KODAK EDR2 ready-pack film which was used to develop the step valley dose maps and the IMRT QA planar doses. A comparison between the step valley technique and multifilm based calibration showed that both calibration methods agreed with less than 0.4% deviation in the clinically useful dose ranges.

  9. Patient dose estimation from CT scans at the Mexican National Neurology and Neurosurgery Institute

    SciTech Connect (OSTI)

    Alva-Sánchez, Héctor

    2014-11-07

    In the radiology department of the Mexican National Institute of Neurology and Neurosurgery, a dedicated institute in Mexico City, on average 19.3 computed tomography (CT) examinations are performed daily on hospitalized patients for neurological disease diagnosis, control scans and follow-up imaging. The purpose of this work was to estimate the effective dose received by hospitalized patients who underwent a diagnostic CT scan using typical effective dose values for all CT types and to obtain the estimated effective dose distributions received by surgical and non-surgical patients. Effective patient doses were estimated from values per study type reported in the applications guide provided by the scanner manufacturer. This retrospective study included all hospitalized patients who underwent a diagnostic CT scan between 1 January 2011 and 31 December 2012. A total of 8777 CT scans were performed in this two-year period. Simple brain scan was the CT type performed the most (74.3%) followed by contrasted brain scan (6.1%) and head angiotomography (5.7%). The average number of CT scans per patient was 2.83; the average effective dose per patient was 7.9 mSv; the mean estimated radiation dose was significantly higher for surgical (9.1 mSv) than non-surgical patients (6.0 mSv). Three percent of the patients had 10 or more brain CT scans and exceeded the organ radiation dose threshold set by the International Commission on Radiological Protection for deterministic effects of the eye-lens. Although radiation patient doses from CT scans were in general relatively low, 187 patients received a high effective dose (>20 mSv) and 3% might develop cataract from cumulative doses to the eye lens.

  10. Evaluating IMRT and VMAT dose accuracy: Practical examples of failure to detect systematic errors when applying a commonly used metric and action levels

    SciTech Connect (OSTI)

    Nelms, Benjamin E.; Chan, Maria F.; Jarry, Genevive; Lemire, Matthieu; Lowden, John; Hampton, Carnell

    2013-11-15

    Purpose: This study (1) examines a variety of real-world cases where systematic errors were not detected by widely accepted methods for IMRT/VMAT dosimetric accuracy evaluation, and (2) drills-down to identify failure modes and their corresponding means for detection, diagnosis, and mitigation. The primary goal of detailing these case studies is to explore different, more sensitive methods and metrics that could be used more effectively for evaluating accuracy of dose algorithms, delivery systems, and QA devices.Methods: The authors present seven real-world case studies representing a variety of combinations of the treatment planning system (TPS), linac, delivery modality, and systematic error type. These case studies are typical to what might be used as part of an IMRT or VMAT commissioning test suite, varying in complexity. Each case study is analyzed according to TG-119 instructions for gamma passing rates and action levels for per-beam and/or composite plan dosimetric QA. Then, each case study is analyzed in-depth with advanced diagnostic methods (dose profile examination, EPID-based measurements, dose difference pattern analysis, 3D measurement-guided dose reconstruction, and dose grid inspection) and more sensitive metrics (2% local normalization/2 mm DTA and estimated DVH comparisons).Results: For these case studies, the conventional 3%/3 mm gamma passing rates exceeded 99% for IMRT per-beam analyses and ranged from 93.9% to 100% for composite plan dose analysis, well above the TG-119 action levels of 90% and 88%, respectively. However, all cases had systematic errors that were detected only by using advanced diagnostic techniques and more sensitive metrics. The systematic errors caused variable but noteworthy impact, including estimated target dose coverage loss of up to 5.5% and local dose deviations up to 31.5%. Types of errors included TPS model settings, algorithm limitations, and modeling and alignment of QA phantoms in the TPS. Most of the errors were correctable after detection and diagnosis, and the uncorrectable errors provided useful information about system limitations, which is another key element of system commissioning.Conclusions: Many forms of relevant systematic errors can go undetected when the currently prevalent metrics for IMRT/VMAT commissioning are used. If alternative methods and metrics are used instead of (or in addition to) the conventional metrics, these errors are more likely to be detected, and only once they are detected can they be properly diagnosed and rooted out of the system. Removing systematic errors should be a goal not only of commissioning by the end users but also product validation by the manufacturers. For any systematic errors that cannot be removed, detecting and quantifying them is important as it will help the physicist understand the limits of the system and work with the manufacturer on improvements. In summary, IMRT and VMAT commissioning, along with product validation, would benefit from the retirement of the 3%/3 mm passing rates as a primary metric of performance, and the adoption instead of tighter tolerances, more diligent diagnostics, and more thorough analysis.

  11. Assessment of potential doses to workers during postulated accident conditions at the Waste Isolation Pilot Plant

    SciTech Connect (OSTI)

    Hoover, M.D.; Newton, G.J.; Farrell, R.F.

    1996-06-01

    This qualitative hazard evaluation systematically assessed potential doses to workers during postulated accident conditions at the U.S. Department of Energy`s Waste Isolation Pilot Plant (WIPP). Postulated accidents included the spontaneous ignition of a waste drum, puncture of a waste drum by a forklift, dropping of a waste drum from a forklift, and simultaneous dropping of seven drums during a crane failure. The descriptions and estimated frequencies of occurrence for these accidents were developed by the Hazard and Operability Study for CH TRU Waste Handling System (WCAP 14312). The estimated materials at risk, damage ratios, airborne release fractions and respirable fractions for these accidents were taken from the 1995 Safety Analysis Report (SAR) update and from the DOE handbook Airborne Release Fractions/Rates and Respirable Fractions for Nonreactor Nuclear Facilities (DOE-HDBK-3010-94). A Monte Carlo simulation was used to estimate the range of worker exposures that could result from each accident. Guidelines for evaluating the adequacy of defense-in-depth for worker protection at WIPP were adopted from a scheme presented by the International Commission on Radiological Protection in its publication on Protection from Potential Exposure: A Conceptual Framework (ICRP Publication 64). Probabilities of exposures greater than 5, 50, and 300 rem were less than 10{sup -2}, 10{sup -4}, and 10{sup -6} per year, respectively. In conformance with the guidance of DOE standard 3009-94, Appendix A (draft), we emphasize that use of these evaluation guidelines is not intended to imply that these numbers constitute acceptable limits for worker exposure under accident conditions. However, in conjunction with the extensive safety assessment in the 1995 SAR update, these results indicate that the Carlsbad Area Office strategy for the assessment of hazards and accidents assures the protection of workers, as well as members of the public and the environment.

  12. SU-E-J-63: Estimating the Effects of Respiratory Motion On Dose Heterogeneity for ITV-Based Treatments

    SciTech Connect (OSTI)

    Williams, C; Lewis, J

    2014-06-01

    Purpose: To quantify the relationship between the amount of dose heterogeneity in a treatment plan that uses an internal target volume (ITV) to account for respiratory motion and the true amount of heterogeneity in the dose delivered to the tumor contained within that ITV. Methods: We develop a convolution-based framework for calculating dose delivered to a tumor moving inside an ITV according to a common sinusoid-based breathing model including asymmetry. We model the planned ITV dose distribution as a centrally peaked analytic function approximating the profile of clinical stereotactic body radiotherapy treatments. Expressions for the minimum and maximum dose received by the tumor are derived and evaluated for a range of clinically relevant parameters. Results of the model are validated with phantom measurements using an ion chamber array. Results: An analytic expression is presented for the maximum and minimum doses received by the tumor relative to the planned ITV dose. The tumor dose heterogeneity depends solely on the ratio of tumor size to ITV size, the peak dose in the planned ITV dose distribution, and the respiratory asymmetry parameter. Under the assumptions of this model, using a typical breathing asymmetry parameter and a dose distribution with a fixed size ITV covered by the 100% line and with a 130% hotspot, the maximum dose to the tumor varies between 113%130%, and the minimum dose varies between 100%116% depending on the amount of tumor motion. Conclusion: This modeling exercise demonstrates the interplay between motion and dose heterogeneity. Tumors that exhibit large amounts of respiratory motion relative to their size will receive a more homogeneous dose and a larger minimum dose than would be inferred from the ITV dose distribution. This effect is not captured in current clinical treatment planning methods unless 4D dose calculation techniques are used. This work was partially supported by a Varian Medical Systems research grant.

  13. The effects of gantry tilt on breast dose and image noise in cardiac CT

    SciTech Connect (OSTI)

    Hoppe, Michael E.; Gandhi, Diksha; Schmidt, Taly Gilat; Stevens, Grant M.; Foley, W. Dennis

    2013-12-15

    Purpose: This study investigated the effects of tilted-gantry acquisition on image noise and glandular breast dose in females during cardiac computed tomography (CT) scans. Reducing the dose to glandular breast tissue is important due to its high radiosensitivity and limited diagnostic significance in cardiac CT scans.Methods: Tilted-gantry acquisition was investigated through computer simulations and experimental measurements. Upon IRB approval, eight voxelized phantoms were constructed from previously acquired cardiac CT datasets. Monte Carlo simulations quantified the dose deposited in glandular breast tissue over a range of tilt angles. The effects of tilted-gantry acquisition on breast dose were measured on a clinical CT scanner (CT750HD, GE Healthcare) using an anthropomorphic phantom with MOSFET dosimeters in the breast regions. In both simulations and experiments, scans were performed at gantry tilt angles of 0°–30°, in 5° increments. The percent change in breast dose was calculated relative to the nontilted scan for all tilt angles. The percent change in noise standard deviation due to gantry tilt was calculated in all reconstructed simulated and experimental images.Results: Tilting the gantry reduced the breast dose in all simulated and experimental phantoms, with generally greater dose reduction at increased gantry tilts. For example, at 30° gantry tilt, the dosimeters located in the superior, middle, and inferior breast regions measured dose reductions of 74%, 61%, and 9%, respectively. The simulations estimated 0%–30% total breast dose reduction across the eight phantoms and range of tilt angles. However, tilted-gantry acquisition also increased the noise standard deviation in the simulated phantoms by 2%–50% due to increased pathlength through the iodine-filled heart. The experimental phantom, which did not contain iodine in the blood, demonstrated decreased breast dose and decreased noise at all gantry tilt angles.Conclusions: Tilting the gantry reduced the dose to the breast, while also increasing noise standard deviation. Overall, the noise increase outweighed the dose reduction for the eight voxelized phantoms, suggesting that tilted gantry acquisition may not be beneficial for reducing breast dose while maintaining image quality.

  14. Commercial Buildings Asset Rating Program RFI | Department of Energy

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

    Buildings Asset Rating Program RFI Commercial Buildings Asset Rating Program RFI DEPARTMENT OF ENERGY Office of Energy Efficiency and Renewable Energy [Docket Number EERE…2011…BT…NOA…0049] PDF icon asset_rating_rfi.pdf More Documents & Publications Commercial Building Asset Rating Program Building Energy Asset Score: Architects EIS-0459: Amended Notice of Intent for a Programmatic Environmental Impact Statement

  15. 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.

  16. Fast dose kernel interpolation using Fourier transform with application to permanent prostate brachytherapy dosimetry

    SciTech Connect (OSTI)

    Liu, Derek Sloboda, Ron S.

    2014-05-15

    Purpose: Boyer and Mok proposed a fast calculation method employing the Fourier transform (FT), for which calculation time is independent of the number of seeds but seed placement is restricted to calculation grid points. Here an interpolation method is described enabling unrestricted seed placement while preserving the computational efficiency of the original method. Methods: The Iodine-125 seed dose kernel was sampled and selected values were modified to optimize interpolation accuracy for clinically relevant doses. For each seed, the kernel was shifted to the nearest grid point via convolution with a unit impulse, implemented in the Fourier domain. The remaining fractional shift was performed using a piecewise third-order Lagrange filter. Results: Implementation of the interpolation method greatly improved FT-based dose calculation accuracy. The dose distribution was accurate to within 2% beyond 3 mm from each seed. Isodose contours were indistinguishable from explicit TG-43 calculation. Dose-volume metric errors were negligible. Computation time for the FT interpolation method was essentially the same as Boyer's method. Conclusions: A FT interpolation method for permanent prostate brachytherapy TG-43 dose calculation was developed which expands upon Boyer's original method and enables unrestricted seed placement. The proposed method substantially improves the clinically relevant dose accuracy with negligible additional computation cost, preserving the efficiency of the original method.

  17. Evaluation of GafChromic EBT prototype B for external beam dose verification

    SciTech Connect (OSTI)

    Todorovic, M.; Fischer, M.; Cremers, F.; Thom, E.; Schmidt, R.

    2006-05-15

    The capability of the new GafChromic EBT prototype B for external beam dose verification is investigated in this paper. First the general characteristics of this film (dose response, postirradiation coloration, influence of calibration field size) were derived using a flat-bed scanner. In the dose range from 0.1 to 8 Gy, the sensitivity of the EBT prototype B film is ten times higher than the response of the GafChromic HS, which so far was the GafChromic film with the highest sensitivity. Compared with the Kodak EDR2 film, the response of the EBT is higher by a factor of 3 in the dose range from 0.1 to 8 Gy. The GafChromic EBT almost does not show a temporal growth of the optical density and there is no influence of the chosen calibration field size on the dose response curve obtained from this data. A MatLab program was written to evaluate the two-dimensional dose distributions from treatment planning systems and GafChromic EBT film measurements. Verification of external beam therapy (SRT, IMRT) using the above-mentioned approach resulted in very small differences between the planned and the applied dose. The GafChromic EBT prototype B together with the flat-bed scanner and MatLab is a successful approach for making the advantages of the GafChromic films applicable for verification of external beam therapy.

  18. Modelling and mitigating dose to firefighters from inhalation of radionuclides in wildland fire smoke

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

    Viner, Brian J.; Jannik, Tim; Stone, Daniel; Hepworth, Allan; Naeher, Luke; Adetona, Olorunfemi; Blake, John; Eddy, Teresa

    2015-06-12

    Firefighters responding to wildland fires where surface litter and vegetation contain radiological contamination will receive a radiological dose by inhaling resuspended radioactive material in the smoke. This may increase their lifetime risk of contracting certain types of cancer. Using published data, we modelled hypothetical radionuclide emissions, dispersion and dose for 70th and 97th percentile environmental conditions and for average and high fuel loads at the Savannah River Site. We predicted downwind concentration and potential dose to firefighters for radionuclides of interest (137Cs, 238Pu, 90Sr and 210Po). Predicted concentrations exceeded dose guidelines in the base case scenario emissions of 1.0 ×more » 107 Bq ha–1 for 238Pu at 70th percentile environmental conditions and average fuel load levels for both 4- and 14-h shifts. Under 97th percentile environmental conditions and high fuel loads, dose guidelines were exceeded for several reported cases for 90Sr, 238Pu and 210Po. Potential for exceeding dose guidelines was mitigated by including plume rise (>2 m s–1) or moving a small distance from the fire owing to large concentration gradients near the edge of the fire. As a result, our approach can quickly estimate potential dose from airborne radionuclides in wildland fire and assist decision-making to reduce firefighter exposure.« less

  19. Modelling and mitigating dose to firefighters from inhalation of radionuclides in wildland fire smoke.

    SciTech Connect (OSTI)

    Viner, Brian J.

    2015-06-12

    Firefighters responding to wildland fires where surface litter and vegetation contain radiological contamination will receive a radiological dose by inhaling resuspended radioactive material in the smoke. This may increase their lifetime risk of contracting certain types of cancer. Using published data, we modelled hypothetical radionuclide emissions, dispersion and dose for 70th and 97th percentile environmental conditions and for average and high fuel loads at the Savannah River Site. We predicted downwind concentration and potential dose to firefighters for radionuclides of interest (137Cs, 238Pu, 90Sr and 210Po). Predicted concentrations exceeded dose guidelines in the base case scenario emissions of 1.0 x 107Bq ha-1 for 238Pu at 70th percentile environmental conditions and average fuel load levels for both 4- and 14-h shifts. Under 97th percentile environmental conditions and high fuel loads, dose guidelines were exceeded for several reported cases for 90Sr, 238Pu and 210Po. The potential for exceeding dose guidelines was mitigated by including plume rise (>2ms-1) or moving a small distance from the fire owing to large concentration gradients near the edge of the fire. This approach can quickly estimate potential dose from airborne radionuclides in wildland fire and assist decision-making to reduce firefighter exposure.

  20. Modelling and mitigating dose to firefighters from inhalation of radionuclides in wildland fire smoke

    SciTech Connect (OSTI)

    Viner, Brian J.; Jannik, Tim; Stone, Daniel; Hepworth, Allan; Naeher, Luke; Adetona, Olorunfemi; Blake, John; Eddy, Teresa

    2015-06-12

    Firefighters responding to wildland fires where surface litter and vegetation contain radiological contamination will receive a radiological dose by inhaling resuspended radioactive material in the smoke. This may increase their lifetime risk of contracting certain types of cancer. Using published data, we modelled hypothetical radionuclide emissions, dispersion and dose for 70th and 97th percentile environmental conditions and for average and high fuel loads at the Savannah River Site. We predicted downwind concentration and potential dose to firefighters for radionuclides of interest (137Cs, 238Pu, 90Sr and 210Po). Predicted concentrations exceeded dose guidelines in the base case scenario emissions of 1.0 107 Bq ha1 for 238Pu at 70th percentile environmental conditions and average fuel load levels for both 4- and 14-h shifts. Under 97th percentile environmental conditions and high fuel loads, dose guidelines were exceeded for several reported cases for 90Sr, 238Pu and 210Po. Potential for exceeding dose guidelines was mitigated by including plume rise (>2 m s1) or moving a small distance from the fire owing to large concentration gradients near the edge of the fire. As a result, our approach can quickly estimate potential dose from airborne radionuclides in wildland fire and assist decision-making to reduce firefighter exposure.

  1. Extremum seeking with bounded update rates

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

    Scheinker, Alexander; Krstić, Miroslav

    2013-11-16

    In this work, we present a form of extremum seeking (ES) in which the unknown function being minimized enters the system’s dynamics as the argument of a cosine or sine term, thereby guaranteeing known bounds on update rates and control efforts. We present general n-dimensional optimization and stabilization results as well as 2D vehicle control, with bounded velocity and control efforts. For application to autonomous vehicles, tracking a source in a GPS denied environment with unknown orientation, this ES approach allows for smooth heading angle actuation, with constant velocity, and in application to a unicycle-type vehicle results in control abilitymore » as if the vehicle is fully actuated. Our stability analysis is made possible by the classic results of Kurzweil, Jarnik, Sussmann, and Liu, regarding systems with highly oscillatory terms. In our stability analysis, we combine the averaging results with a semi-global practical stability result under small parametric perturbations developed by Moreau and Aeyels.« less

  2. Solids flow rate measurement in dense slurries

    SciTech Connect (OSTI)

    Porges, K.G.; Doss, E.D.

    1993-09-01

    Accurate and rapid flow rate measurement of solids in dense slurries remains an unsolved technical problem, with important industrial applications in chemical processing plants and long-distance solids conveyance. In a hostile two-phase medium, such a measurement calls for two independent parameter determinations, both by non-intrusive means. Typically, dense slurries tend to flow in laminar, non-Newtonian mode, eliminating most conventional means that usually rely on calibration (which becomes more difficult and costly for high pressure and temperature media). These issues are reviewed, and specific solutions are recommended in this report. Detailed calculations that lead to improved measuring device designs are presented for both bulk density and average velocity measurements. Cross-correlation, chosen here for the latter task, has long been too inaccurate for practical applications. The cause and the cure of this deficiency are discussed using theory-supported modeling. Fluid Mechanics are used to develop the velocity profiles of laminar non-Newtonian flow in a rectangular duct. This geometry uniquely allows the design of highly accurate `capacitive` devices and also lends itself to gamma transmission densitometry on an absolute basis. An absolute readout, though of less accuracy, is also available from a capacitive densitometer and a pair of capacitive sensors yields signals suitable for cross-correlation velocity measurement.

  3. PBXN-9 Ignition Kinetics and Deflagration Rates

    SciTech Connect (OSTI)

    Glascoe, E; Maienschein, J; Burnham, A; Koerner, J; Hsu, P; Wemhoff, A

    2008-04-24

    The ignition kinetics and deflagration rates of PBXN-9 were measured using specially designed instruments at LLNL and compared with previous work on similar HMX based materials. Ignition kinetics were measured based on the One Dimensional Time-to-Explosion combined with ALE3D modeling. Results of these experiments indicate that PBXN-9 behaves much like other HMX based materials (i.e. LX-04, LX-07, LX-10 and PBX-9501) and the dominant factor in these experiments is the type of explosive, not the type of binder/plasticizer. In contrast, the deflagration behavior of PBXN-9 is quite different from similar high weight percent HMX based materials (i.e LX-10, LX-07 and PBX-9501). PBXN-9 burns in a laminar manner over the full pressure range studied (0-310 MPa) unlike LX-10, LX-07, and PBX-9501. The difference in deflagration behavior is attributed to the nature of the binder/plasticizer alone or in conjunction with the volume of binder present in PBXN-9.

  4. What Is the Right Rate? Loan Rates and Demand | Department of Energy

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

    Neighborhood Program Financing Peer Exchange Call: "What is the Right Rate?" call slides and discussion summary, December 1, 2011. PDF icon Call Slides and Discussion Summary More Documents & Publications Structuring Rebate and Incentive Programs for Sustainable Demand Peer Exchange Call on Financing and Revenue: Bond Funding Financing Small Business Upgrades

  5. SU-E-P-03: Implementing a Low Dose Lung Screening CT Program Meeting Regulatory Requirements

    SciTech Connect (OSTI)

    LaFrance, M; Marsh, S; O'Donnell, G

    2014-06-01

    Purpose: To provide information pertaining to IROC Houston QA Center's (RPC) credentialing process for institutions participating in NCI-sponsored clinical trials. Purpose: Provide guidance to the Radiology Departments with the intent of implementing a Low Dose CT Screening Program using different CT Scanners with multiple techniques within the framework of the required state regulations. Method: State Requirements for the purpose of implementing a Low Dose CT Lung Protocol required working with the Radiology and Pulmonary Department in setting up a Low Dose Screening Protocol designed to reduce the radiation burden to the patients enrolled. Radiation dose measurements (CTDIvol) for various CT manufacturers (Siemens16, Siemens 64, Philips 64, and Neusoft128) for three different weight based protocols. All scans were reviewed by the Radiologist. Prior to starting a low dose lung screening protocol, information had to be submitted to the state for approval. Performing a Healing Arts protocol requires extensive information. This not only includes name and address of the applicant but a detailed description of the disease, the x-ray examination and the population to be examined. The unit had to be tested by a qualified expert using the technique charts. The credentials of all the operators, the supervisors and the Radiologists had to be submitted to the state. Results: All the appropriate documentation was sent to the state for review. The measured results between the Low Dose Protocol versus the default Adult Chest Protocol showed that there was a dose reduction of 65% for small (100-150 lb.) patient, 75% for the Medium patient (151-250 lbs.), and a 55% reduction for the Large patient ( over 250 lbs.). Conclusion: Measured results indicated that the Low Dose Protocol indeed lowered the screening patient's radiation dose and the institution was able to submit the protocol to the State's regulators.

  6. A low dose simulation tool for CT systems with energy integrating detectors

    SciTech Connect (OSTI)

    Zabic, Stanislav; Morton, Thomas; Brown, Kevin M.; Wang Qiu

    2013-03-15

    Purpose: This paper introduces a new strategy for simulating low-dose computed tomography (CT) scans using real scans of a higher dose as an input. The tool is verified against simulations and real scans and compared to other approaches found in the literature. Methods: The conditional variance identity is used to properly account for the variance of the input high-dose data, and a formula is derived for generating a new Poisson noise realization which has the same mean and variance as the true low-dose data. The authors also derive a formula for the inclusion of real samples of detector noise, properly scaled according to the level of the simulated x-ray signals. Results: The proposed method is shown to match real scans in number of experiments. Noise standard deviation measurements in simulated low-dose reconstructions of a 35 cm water phantom match real scans in a range from 500 to 10 mA with less than 5% error. Mean and variance of individual detector channels are shown to match closely across the detector array. Finally, the visual appearance of noise and streak artifacts is shown to match in real scans even under conditions of photon-starvation (with tube currents as low as 10 and 80 mA). Additionally, the proposed method is shown to be more accurate than previous approaches (1) in achieving the correct mean and variance in reconstructed images from pure-Poisson noise simulations (with no detector noise) under photon-starvation conditions, and (2) in simulating the correct noise level and detector noise artifacts in real low-dose scans. Conclusions: The proposed method can accurately simulate low-dose CT data starting from high-dose data, including effects from photon starvation and detector noise. This is potentially a very useful tool in helping to determine minimum dose requirements for a wide range of clinical protocols and advanced reconstruction algorithms.

  7. Estimation of organ and effective dose due to Compton backscatter security scans

    SciTech Connect (OSTI)

    Hoppe, Michael E.; Schmidt, Taly Gilat

    2012-06-15

    Purpose: To estimate organ and effective radiation doses due to backscatter security scanners using Monte Carlo simulations and a voxelized phantom set. Methods: Voxelized phantoms of male and female adults and children were used with the GEANT4 toolkit to simulate a backscatter security scan. The backscatter system was modeled based on specifications available in the literature. The simulations modeled a 50 kVp spectrum with 1.0 mm-aluminum-equivalent filtration and a previously measured exposure of approximately 4.6 {mu}R at 30 cm from the source. Photons and secondary interactions were tracked from the source until they reached zero kinetic energy or exited from the simulation's boundaries. The energy deposited in the phantoms' respective organs was tallied and used to calculate total organ dose and total effective dose for frontal, rear, and full scans with subjects located 30 and 75 cm from the source. Results: For a full screen, all phantoms' total effective doses were below the established 0.25 {mu}Sv standard, with an estimated maximum total effective dose of 0.07 {mu}Sv for full screen of a male child. The estimated maximum organ dose due to a full screen was 1.03 {mu}Gy, deposited in the adipose tissue of the male child phantom when located 30 cm from the source. All organ dose estimates had a coefficient of variation of less than 3% for a frontal scan and less than 11% for a rear scan. Conclusions: Backscatter security scanners deposit dose in organs beyond the skin. The effective dose is below recommended standards set by the Health Physics Society (HPS) and the American National Standards Institute (ANSI) assuming the system provides a maximum exposure of approximately 4.6 {mu}R at 30 cm.

  8. Energy Escalation Rate Calculator Download | Department of Energy

    Office of Environmental Management (EM)

    Escalation Rate Calculator Download Energy Escalation Rate Calculator Download The Energy Escalation Rate Calculator (EERC) computes an average annual escalation rate for a specified time period, which can be used as an escalation rate for contract payments in energy savings performance contracts and utility energy services contracts. You can download EERC 2.0-15 by clicking on the link for your operating system below. Windows: After downloading, double-click eerc_install.exe. Mac OS X: After

  9. Energy Performance Ratings for Windows, Doors, and Skylights | Department

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

    of Energy Energy Performance Ratings for Windows, Doors, and Skylights Energy Performance Ratings for Windows, Doors, and Skylights Before you shop for energy-efficient windows, doors, and skylights, learn about energy performance ratings. | Photo courtesy of iStockphoto.com/JamesBrey. Before you shop for energy-efficient windows, doors, and skylights, learn about energy performance ratings. | Photo courtesy of iStockphoto.com/JamesBrey. You can use the energy performance ratings of windows,

  10. SU-E-J-204: Radiation Dose to Patients Resulting From Image Guidance Procedures and AAPM TG-180 Update

    SciTech Connect (OSTI)

    Ding, G; Alaei, P

    2014-06-01

    Purpose: Image-guided radiation therapy (IGRT) is the new paradigm for patient positioning and target localization in radiotherapy. Daily imaging procedures add additional dose to the patient's treatment volume and normal tissues and may expose the organs at risk to unaccounted doses. This presentation is to update the progress of AAPM TG-180 which aims to provide strategies to quantify and account the dose from both MV and kV imaging in patient treatment planning. Methods: Our current knowledge on image guidance dose is presented. A summary of doses from image guidance procedures delivered to patients in relationship with therapeutic doses is given. Different techniques in reducing the image guidance dose are summarized. Typical organ doses resulting from different image acquisition procedures used in IGRT are tabulated. Results: Many techniques to reduce the imaging doses are available in clinical applications. There are large variations between dose to bone and dose to soft tissues for x-rays at kilovoltage energy range. Methods for clinical implementation of accounting for the imaging dose from an imaging procedure are available. Beam data from imaging systems can be generated by combining Monte Carlo simulations and experimental measurements for commissioning imaging beams in the treatment planning. Conclusion: The current treatment planning systems are not yet equipped to perform patient specific dose calculations resulting from kV imaging procedures. The imaging dose from current kV image devices has been significantly reduced and is generally much less than that resulting from MV. Because the magnitude of kV imaging dose is significantly low and the variation between patients is modest, it is feasible to estimate dose based on imaging producers or protocols using tabulated values which provides an alternative to accomplish the task of accounting and reporting imaging doses.

  11. WE-E-BRE-04: Dual Focal Spot Dose Painting for Precision Preclinical Radiobiological Investigations

    SciTech Connect (OSTI)

    Stewart, J; Lindsay, P; Jaffray, D

    2014-06-15

    Purpose: Recent progress in small animal radiotherapy systems has provided the foundation for delivering the heterogeneous, millimeter scale dose distributions demanded by preclinical radiobiology investigations. Despite advances in preclinical dose planning, delivery of highly heterogeneous dose distributions is constrained by the fixed collimation systems and large x-ray focal spot common in small animal radiotherapy systems. This work proposes a dual focal spot dose optimization and delivery method with a large x-ray focal spot used to deliver homogeneous dose regions and a small focal spot to paint spatially heterogeneous dose regions. Methods: Two-dimensional dose kernels were measured for a 1 mm circular collimator with radiochromic film at 10 mm depth in a solid water phantom for the small and large x-ray focal spots on a recently developed small animal microirradiator. These kernels were used in an optimization framework which segmented a desired dose distribution into low- and high-spatial frequency regions for delivery by the large and small focal spot, respectively. For each region, the method determined an optimal set of stage positions and beam-on times. The method was demonstrated by optimizing a bullseye pattern consisting of 0.75 mm radius circular target and 0.5 and 1.0 mm wide rings alternating between 0 and 2 Gy. Results: Compared to a large focal spot technique, the dual focal spot technique improved the optimized dose distribution: 69.2% of the optimized dose was within 0.5 Gy of the intended dose for the large focal spot, compared to 80.6% for the dual focal spot method. The dual focal spot design required 14.0 minutes of optimization, and will require 178.3 minutes for automated delivery. Conclusion: The dual focal spot optimization and delivery framework is a novel option for delivering conformal and heterogeneous dose distributions at the preclinical level and provides a new experimental option for unique radiobiological investigations. Funding Support: this work is supported by funding the National Sciences and Engineering Research Council of Canada, and a Mitacs-accelerate fellowship. Conflict of Interest: Dr. Lindsay and Dr. Jaffray are listed as inventors of the small animal microirradiator described herein. This system has been licensed for commercial development.

  12. A New Approach in Urea Dosing to Improve Performance and Durability of SCR

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

    Systems for the Use in Off-Road Applications to Fulfill Tier 4 Final | Department of Energy Approach in Urea Dosing to Improve Performance and Durability of SCR Systems for the Use in Off-Road Applications to Fulfill Tier 4 Final A New Approach in Urea Dosing to Improve Performance and Durability of SCR Systems for the Use in Off-Road Applications to Fulfill Tier 4 Final Evaluation of influence of spray quality on urea decomposition and catalyst performance leads to new approach in dosing,

  13. Dose distribution from x-ray microbeam arrays applied to radiation therapy:

    Office of Scientific and Technical Information (OSTI)

    An EGS4 Monte Carlo study (Journal Article) | SciTech Connect Dose distribution from x-ray microbeam arrays applied to radiation therapy: An EGS4 Monte Carlo study Citation Details In-Document Search Title: Dose distribution from x-ray microbeam arrays applied to radiation therapy: An EGS4 Monte Carlo study We present EGS4 Monte Carlo calculations of the spatial distribution of the dose deposited by a single x-ray pencil beam, a planar microbeam, and an array of parallel planar microbeams as

  14. Determination of In-Vitro Lung Solubility and Intake-To-Dose Conversion

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

    Factors for Tritiated LaNi4.25Al0.75 Hydride | Department of Energy Determination of In-Vitro Lung Solubility and Intake-To-Dose Conversion Factors for Tritiated LaNi4.25Al0.75 Hydride Determination of In-Vitro Lung Solubility and Intake-To-Dose Conversion Factors for Tritiated LaNi4.25Al0.75 Hydride Presentation from the 34th Tritium Focus Group Meeting held in Idaho Falls, Idaho on September 23-25, 2014. PDF icon Determination of In-Vitro Lung Solubility and Intake-To-Dose Conversion

  15. SU-E-T-426: Dose Delivery Accuracy in Breast Field Junction for Free Breath

    Office of Scientific and Technical Information (OSTI)

    and Deep Inspiration Breath Hold Techniques (Journal Article) | SciTech Connect SU-E-T-426: Dose Delivery Accuracy in Breast Field Junction for Free Breath and Deep Inspiration Breath Hold Techniques Citation Details In-Document Search Title: SU-E-T-426: Dose Delivery Accuracy in Breast Field Junction for Free Breath and Deep Inspiration Breath Hold Techniques Purpose: The purpose of this work was to verify the accuracy of the dose distribution along the field junction in a half beam

  16. SU-E-T-157: Evaluation and Comparison of Doses to Pelvic Lymph Nodes and to Point B with 3D Image Guided Treatment Planning for High Dose Brachytherapy for Treatment of Cervical Cancer

    SciTech Connect (OSTI)

    Bhandare, N.

    2014-06-01

    Purpose: To estimate and compare the doses received by the obturator, external and internal iliac lymph nodes and point Methods: CT-MR fused image sets of 15 patients obtained for each of 5 fractions of HDR brachytherapy using tandem and ring applicator, were used to generate treatment plans optimized to deliver a prescription dose to HRCTV-D90 and to minimize the doses to organs at risk (OARs). For each set of image, target volume (GTV, HRCTV) OARs (Bladder, Rectum, Sigmoid), and both left and right pelvic lymph nodes (obturator, external and internal iliac lymph nodes) were delineated. Dose-volume histograms (DVH) were generated for pelvic nodal groups (left and right obturator group, internal and external iliac chains) Per fraction DVH parameters used for dose comparison included dose to 100% volume (D100), and dose received by 2cc (D2cc), 1cc (D1cc) and 0.1 cc (D0.1cc) of nodal volume. Dose to point B was compared with each DVH parameter using 2 sided t-test. Pearson correlation were determined to examine relationship of point B dose with nodal DVH parameters. Results: FIGO clinical stage varied from 1B1 to IIIB. The median pretreatment tumor diameter measured on MRI was 4.5 cm (2.7 6.4cm).The median dose to bilateral point B was 1.20 Gy 0.12 or 20% of the prescription dose. The correlation coefficients were all <0.60 for all nodal DVH parameters indicating low degree of correlation. Only 2 cc of obturator nodes was not significantly different from point B dose on t-test. Conclusion: Dose to point B does not adequately represent the dose to any specific pelvic nodal group. When using image guided 3D dose-volume optimized treatment nodal groups should be individually identified and delineated to obtain the doses received by pelvic nodes.

  17. Low-Dose Spiral CT Scans for Early Lung Cancer Detection

    Broader source: Energy.gov [DOE]

    Low-dose spiral computed tomography (CT) scanning is a noninvasive medical imaging test that has been used for the early detection of lung cancer for over 16 years (Sone et al. 1998; Henschke et.al. 1999).

  18. Calculation of radiation therapy dose using all particle Monte Carlo transport

    DOE Patents [OSTI]

    Chandler, William P. (Tracy, CA); Hartmann-Siantar, Christine L. (San Ramon, CA); Rathkopf, James A. (Livermore, CA)

    1999-01-01

    The actual radiation dose absorbed in the body is calculated using three-dimensional Monte Carlo transport. Neutrons, protons, deuterons, tritons, helium-3, alpha particles, photons, electrons, and positrons are transported in a completely coupled manner, using this Monte Carlo All-Particle Method (MCAPM). The major elements of the invention include: computer hardware, user description of the patient, description of the radiation source, physical databases, Monte Carlo transport, and output of dose distributions. This facilitated the estimation of dose distributions on a Cartesian grid for neutrons, photons, electrons, positrons, and heavy charged-particles incident on any biological target, with resolutions ranging from microns to centimeters. Calculations can be extended to estimate dose distributions on general-geometry (non-Cartesian) grids for biological and/or non-biological media.

  19. Engine-External HC-Dosing for Regeneration of Diesel Particulate...

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

    Filters for Heavy Duty and NRMM According to Annex XXVII StVZO Engine-External HC-Dosing for Regeneration of Diesel Particulate Filters for Heavy Duty and NRMM According to ...

  20. Determination of In-Vitro Lung Solubility and Intake-To-Dose...

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

    Presentation from the 34th Tritium Focus Group Meeting held in Idaho Falls, Idaho on September 23-25, 2014. PDF icon Determination of In-Vitro Lung Solubility and Intake-To-Dose ...

  1. Calculation of radiation therapy dose using all particle Monte Carlo transport

    DOE Patents [OSTI]

    Chandler, W.P.; Hartmann-Siantar, C.L.; Rathkopf, J.A.

    1999-02-09

    The actual radiation dose absorbed in the body is calculated using three-dimensional Monte Carlo transport. Neutrons, protons, deuterons, tritons, helium-3, alpha particles, photons, electrons, and positrons are transported in a completely coupled manner, using this Monte Carlo All-Particle Method (MCAPM). The major elements of the invention include: computer hardware, user description of the patient, description of the radiation source, physical databases, Monte Carlo transport, and output of dose distributions. This facilitated the estimation of dose distributions on a Cartesian grid for neutrons, photons, electrons, positrons, and heavy charged-particles incident on any biological target, with resolutions ranging from microns to centimeters. Calculations can be extended to estimate dose distributions on general-geometry (non-Cartesian) grids for biological and/or non-biological media. 57 figs.

  2. MO-G-BRF-09: Investigating Magnetic Field Dose Effects in Mice: A Monte Carlo Study

    SciTech Connect (OSTI)

    Rubinstein, A; Guindani, M; Followill, D; Melancon, A; Hazle, J; Court, L

    2014-06-15

    Purpose: In MRI-linac treatments, radiation dose distributions are affected by magnetic fields, especially at high-density/low-density interfaces. Radiobiological consequences of magnetic field dose effects are presently unknown; therefore, preclinical studies are needed to ensure the safe clinical use of MRI-linacs. This study investigates the optimal combination of beam energy and magnetic field strength needed for preclinical murine studies. Methods: The Monte Carlo code MCNP6 was used to simulate the effects of a magnetic field when irradiating a mouse-sized lung phantom with a 1.0cmx1.0cm photon beam. Magnetic field effects were examined using various beam energies (225kVp, 662keV[Cs-137], and 1.25MeV[Co-60]) and magnetic field strengths (0.75T, 1.5T, and 3T). The resulting dose distributions were compared to Monte Carlo results for humans with various field sizes and patient geometries using a 6MV/1.5T MRI-linac. Results: In human simulations, the addition of a 1.5T magnetic field caused an average dose increase of 49% (range:36%60%) to lung at the soft tissue-to-lung interface and an average dose decrease of 30% (range:25%36%) at the lung-to-soft tissue interface. In mouse simulations, the magnetic fields had no effect on the 225kVp dose distribution. The dose increases for the Cs-137 beam were 12%, 33%, and 49% for 0.75T, 1.5T, and 3.0T magnetic fields, respectively while the dose decreases were 7%, 23%, and 33%. For the Co-60 beam, the dose increases were 14%, 45%, and 41%, and the dose decreases were 18%, 35%, and 35%. Conclusion: The magnetic field dose effects observed in mouse phantoms using a Co-60 beam with 1.5T or 3T fields and a Cs-137 beam with a 3T field compare well with those seen in simulated human treatments with an MRI-linac. These irradiator/magnet combinations are suitable for preclinical studies investigating potential biological effects of delivering radiation therapy in the presence of a magnetic field. Partially funded by Elekta.

  3. Dose response of selected solid state detectors in applied homogeneous transverse and longitudinal magnetic fields

    SciTech Connect (OSTI)

    Reynolds, M.; Fallone, B. G.; Rathee, S.

    2014-09-15

    Purpose: MR-Linac devices under development worldwide will require standard calibration, commissioning, and quality assurance. Solid state radiation detectors are often used for dose profiles and percent depth dose measurements. The dose response of selected solid state detectors is therefore evaluated in varying transverse and longitudinal magnetic fields for this purpose. Methods: The Monte Carlo code PENELOPE was used to model irradiation of a PTW 60003 diamond detector and IBA PFD diode detector in the presence of a magnetic field. The field itself was varied in strength, and oriented both transversely and longitudinally with respect to the incident photon beam. The long axis of the detectors was oriented either parallel or perpendicular to the photon beam. The dose to the active volume of each detector in air was scored, and its ratio to dose with zero magnetic field strength was determined as the dose response in magnetic field. Measurements at low fields for both detectors in transverse magnetic fields were taken to evaluate the accuracy of the simulations. Additional simulations were performed in a water phantom to obtain few representative points for beam profile and percent depth dose measurements. Results: Simulations show significant dose response as a function of magnetic field in transverse field geometries. This response can be near 20% at 1.5 T, and it is highly dependent on the detectors relative orientation to the magnetic field, the energy of the photon beam, and detector composition. Measurements at low transverse magnetic fields verify the simulations for both detectors in their relative orientations to radiation beam. Longitudinal magnetic fields, in contrast, show little dose response, rising slowly with magnetic field, and reaching 0.5%1% at 1.5 T regardless of detector orientation. Water tank and in air simulation results were the same within simulation uncertainty where lateral electronic equilibrium is present and expectedly differed at the beam edge in transverse field orientations only. Due to the difference in design, the two detectors behaved differently. Conclusions: When transverse magnetic fields are present, great care must be taken when using diamond or diode detectors. Dose response varies with relative detector orientation, magnetic field strength, and between detectors. This response can be considerable (?20% for both detectors). Both detectors in longitudinal fields exhibit little to no dose response as a function of magnetic field. Water tank simulations seem to suggest that the diode detector is better suited to general beam commissioning, and each detector must be investigated separately.

  4. SU-E-T-215: Interactive Dose Shaping: Proof of Concept Study for Six Prostate Patients

    SciTech Connect (OSTI)

    Kamerling, CP [The Institute of Cancer Research and The Royal Marsden NHS Foundation Trust, London (United Kingdom); German Cancer Research Center (DKFZ), Heidelberg (Germany); Ziegenhein, P; Oelfke, U [The Institute of Cancer Research and The Royal Marsden NHS Foundation Trust, London (United Kingdom); Sterzing, F [German Cancer Research Center (DKFZ), Heidelberg (Germany)

    2014-06-01

    Purpose: To provide a proof of concept study for IMRT treatment planning through interactive dose shaping (IDS) by utilising the respective tools to create IMRT treatment plans for six prostate patients. Methods: The IDS planning paradigm aims to perform interactive local dose adaptations of an IMRT plan without compromising already established valuable dose features in real-time. Various IDS tools are available in our in-house treatment planning software Dynaplan and were utilised to create IMRT treatment plans for six patients with an adeno-carcinoma of the prostate. The sequenced IDS treatment plans were compared to conventionally optimised clinically approved plans (9 beams, co-planar). The starting point consisted of open fields. The IDS tools were utilised to sculpt dose out of the rectum and bladder. For each patient, several IDS plans were created, with different trade-offs between organ sparing and target coverage. The reference dose distributions were imported into Dynaplan. For each patient, the IDS treatment plan with a similar or better trade-off between target coverage and OAR sparing was selected for plan evaluation, guided by a physician. Pencil beam dose calculation was performed on a grid with a voxel size of 1.951.952.0 mm{sup 3}. D98%, D2%, mean dose and dose-volume indicators as specified by Quantec were calculated for plan evaluation. Results: It was possible to utilise the software prototype to generate treatment plans for prostate patient geometries in 1545 minutes. Individual local dose adaptations could be performed in less than one second. The average differences compared to the reference plans were for the mean dose: 0.0 Gy (boost) and 1.2 Gy (CTV), for D98%: ?1.1 Gy and for D2%: 1.1 Gy (both target volumes). The dose-volume quality indicators were well below the Quantec constraints. Conclusion: Real-time treatment planning utilising IDS is feasible and has the potential to be implemented clinically. Research at The Institute of Cancer Research is supported by Cancer Research UK under Programme C46/A10588.

  5. SU-E-T-584: Commissioning of the MC2 Monte Carlo Dose Computation Engine

    SciTech Connect (OSTI)

    Titt, U; Mirkovic, D; Liu, A; Ciangaru, G; Mohan, R; Anand, A; Perles, L

    2014-06-01

    Purpose: An automated system, MC2, was developed to convert DICOM proton therapy treatment plans into a sequence MCNPX input files, and submit these to a computing cluster. MC2 converts the results into DICOM format, and any treatment planning system can import the data for comparison vs. conventional dose predictions. This work describes the data and the efforts made to validate the MC2 system against measured dose profiles and how the system was calibrated to predict the correct number of monitor units (MUs) to deliver the prescribed dose. Methods: A set of simulated lateral and longitudinal profiles was compared to data measured for commissioning purposes and during annual quality assurance efforts. Acceptance criteria were relative dose differences smaller than 3% and differences in range (in water) of less than 2 mm. For two out of three double scattering beam lines validation results were already published. Spot checks were performed to assure proper performance. For the small snout, all available measurements were used for validation vs. simulated data. To calibrate the dose per MU, the energy deposition per source proton at the center of the spread out Bragg peaks (SOBPs) was recorded for a set of SOBPs from each option. Subsequently these were then scaled to the results of dose per MU determination based on published methods. The simulations of the doses in the magnetically scanned beam line were also validated vs. measured longitudinal and lateral profiles. The source parameters were fine tuned to achieve maximum agreement with measured data. The dosimetric calibration was performed by scoring energy deposition per proton, and scaling the results to a standard dose measurement of a 10 x 10 x 10 cm3 volume irradiation using 100 MU. Results: All simulated data passed the acceptance criteria. Conclusion: MC2 is fully validated and ready for clinical application.

  6. SU-E-T-27: A Tool for Routine Quality Assurance of Radiotherapy Dose Calculation Software

    SciTech Connect (OSTI)

    Popple, R; Cardan, R; Duan, J; Wu, X; Shen, S; Brezovich, I

    2014-06-01

    Purpose: Dose calculation software is thoroughly evaluated when it is commissioned; however, evaluation of periodic software updates is typically limited in scope due to staffing constraints and the need to quickly return the treatment planning system to clinical service. We developed a tool for quickly and comprehensively testing and documenting dose calculation software against measured data. Methods: A tool was developed using MatLab (The MathWorks, Natick, MA) for evaluation of dose calculation algorithms against measured data. Inputs to the tool are measured data, reference DICOM RT PLAN files describing the measurements, and dose calculations in DICOM format. The tool consists of a collection of extensible modules that can perform analysis of point dose, depth dose curves, and profiles using dose difference, distance-to-agreement, and the gamma-index. Each module generates a report subsection that is incorporated into a master template, which is converted to final form in portable document format (PDF). Results: After each change to the treatment planning system, a report can be generated in approximately 90 minutes. The tool has been in use for more than 5 years, spanning 5 versions of the eMC and 4 versions of the AAA. We have detected changes to the algorithms that affected clinical practice once during this period. Conclusion: Our tool provides an efficient method for quality assurance of dose calculation software, providing a complete set of tests for an update. Future work includes the addition of plan level tests, allowing incorporation of, for example, the TG-119 test suite for IMRT, and integration with the treatment planning system via an application programming interface. Integration with the planning system will permit fully-automated testing and reporting at scheduled intervals.

  7. 131I-Tositumomab Myeloablative Radioimmunotherapy for Non-Hodgkin's Lymphoma: Radiation Dose to the Testes

    SciTech Connect (OSTI)

    Hattori, Naoya; Gopal, Ajay K.; Shields, Andrew T.; Fisher, Darrell R.; Gooley, Ted; Pagel, John M.; Press, Oliver W.; Rajendran, Joseph G.

    2012-12-01

    To investigate radiation dose to testes delivered by radiolabeled anti-CD20 antibody and its effects on male sex hormone levels. METHODS: We evaluated dosimetry results for 67 male patients (54 11 years old) with non-Hodgkin lymphoma who underwent myeloablative radioimmunotherapy (RIT) using 131I-tositumomab. In a subset of patients, male sex hormones were measured before and one year after the therapy. RESULTS: Absorbed dose to testes showed greater variability (range = 4.4 to 70.2 Gy) than did dose to lungs (9.5 to 28.4 Gy, p < 0.0001) or liver (6.5 to 27.2 Gy, p < 0.0001). Absorbed dose to the testes per 131I administered (1.18 0.59 mGy/MBq) was not significantly different from that to the liver (1.03 0.29 mGy/MBq, p = 0.08), or to the lungs (1.19 0.50 mGy/MBq, p = 0.889). Pre-therapy levels of total testosterone were below the lower limit of the reference range, and post-therapy evaluation demonstrated further reduction (4.6 1.8 nmol/L (pre-RIT) vs. 3.8 2.9 nmol/L (post-RIT), p < 0.05). Patients receiving higher radiation doses to the testes (? 25 Gy) showed a greater reduction (4.7 1.6 nmol/L (pre RIT) vs. 3.3 2.7 nmol/L (post-RIT), p < 0.05) than did patients receiving lower doses (< 25 Gy), who showed no significant change in total testosterone levels. CONCLUSION: The testicular radiation absorbed dose varied highly among individual patients. Patients receiving higher doses to testes were more likely to show post-RIT suppression of testosterone levels. Key Words: 131I-tositumomab, follicular lymphoma, radioimmunotherapy, radiation dosimetry, male sex hormones. ?

  8. Effect of particle size and doses of olivine addition on carbon dioxide

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

    sequestration during anaerobic digestion of sewage sludge at ambient and mesophilic temperatures | Argonne National Laboratory Effect of particle size and doses of olivine addition on carbon dioxide sequestration during anaerobic digestion of sewage sludge at ambient and mesophilic temperatures Title Effect of particle size and doses of olivine addition on carbon dioxide sequestration during anaerobic digestion of sewage sludge at ambient and mesophilic temperatures Publication Type Journal

  9. Microsoft Word - Potential Offsite Dose from Divine Strake Rev0 Final.doc

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

    25946--092 POTENTIAL OFFSITE RADIOLOGICAL DOSES ESTIMATED FOR THE PROPOSED DIVINE STRAKE EXPERIMENT, NEVADA TEST SITE December 2006 Revision 0 Prepared for: U.S. Department of Energy National Nuclear Security Administration Nevada Site Office Under Contract No. DE-AC52-06NA25946 Prepared by: National Security Technologies, LLC Las Vegas, NV Potential Offsite Radiological Doses Estimated for the Divine Strake Experiment DOE/NV/25946--092 THIS PAGE INTENTIONALLY LEFT BLANK DOE/NV/25946--092

  10. Individualized 3D Reconstruction of Normal Tissue Dose for Patients With Long-term Follow-up: A Step Toward Understanding Dose Risk for Late Toxicity

    SciTech Connect (OSTI)

    Ng, Angela; Brock, Kristy K.; Sharpe, Michael B.; Department of Radiation Oncology, University of Toronto, Toronto, Ontario ; Moseley, Joanne L.; Craig, Tim; Department of Radiation Oncology, University of Toronto, Toronto, Ontario ; Hodgson, David C.

    2012-11-15

    Purpose: Understanding the relationship between normal tissue dose and delayed radiation toxicity is an important component of developing more effective radiation therapy. Late outcome data are generally available only for patients who have undergone 2-dimensional (2D) treatment plans. The purpose of this study was to evaluate the accuracy of 3D normal tissue dosimetry derived from reconstructed 2D treatment plans in Hodgkin's lymphoma (HL) patients. Methods and Materials: Three-dimensional lung, heart, and breast volumes were reconstructed from 2D planning radiographs for HL patients who received mediastinal radiation therapy. For each organ, a reference 3D organ was modified with patient-specific structural information, using deformable image processing software. Radiation therapy plans were reconstructed by applying treatment parameters obtained from patient records to the reconstructed 3D volumes. For each reconstructed organ mean dose (D{sub mean}) and volumes covered by at least 5 Gy (V{sub 5}) and 20Gy (V{sub 20}) were calculated. This process was performed for 15 patients who had both 2D and 3D planning data available to compare the reconstructed normal tissue doses with those derived from the primary CT planning data and also for 10 historically treated patients with only 2D imaging available. Results: For patients with 3D planning data, the normal tissue doses could be reconstructed accurately using 2D planning data. Median differences in D{sub mean} between reconstructed and actual plans were 0.18 Gy (lungs), -0.15 Gy (heart), and 0.30 Gy (breasts). Median difference in V{sub 5} and V{sub 20} were less than 2% for each organ. Reconstructed 3D dosimetry was substantially higher in historical mantle-field treatments than contemporary involved-field mediastinal treatments: average D{sub mean} values were 15.2 Gy vs 10.6 Gy (lungs), 27.0 Gy vs 14.3 Gy (heart), and 8.0 Gy vs 3.2 Gy (breasts). Conclusions: Three-dimensional reconstruction of absorbed dose to organs at risk can be estimated accurately many years after exposure by using limited 2D data. Compared to contemporary involved-field treatments, normal tissue doses were significantly higher in historical mantle-field treatments. These methods build capacity to quantify the relationship between 3D normal tissue dose and observed late effects.

  11. SIZE DISTRIBUTION AND RATE OF PRODUCTION OF AIRBORNE PARTICULATE MATTER GENERATED DURING METAL CUTTING

    SciTech Connect (OSTI)

    M.A. Ebadian, Ph.D.; S.K. Dua, Ph.D., C.H.P.; Hillol Guha, Ph.D.

    2001-01-01

    During deactivation and decommissioning activities, thermal cutting tools, such as plasma torch, laser, and gasoline torch, are used to cut metals. These activities generate fumes, smoke and particulates. These airborne species of matter, called aerosols, may be inhaled if suitable respiratory protection is not used. Inhalation of the airborne metallic aerosols has been reported to cause ill health effects, such as acute respiratory syndrome and chromosome damage in lymphocytes. In the nuclear industry, metals may be contaminated with radioactive materials. Cutting these metals, as in size reduction of gloveboxes and tanks, produces high concentrations of airborne transuranic particles. Particles of the respirable size range (size < 10 {micro}m) deposit in various compartments of the respiratory tract, the fraction and the site in the respiratory tract depending on the size of the particles. The dose delivered to the respiratory tract depends on the size distribution of the airborne particulates (aerosols) and their concentration and radioactivity/toxicity. The concentration of airborne particulate matter in an environment is dependent upon the rate of their production and the ventilation rate. Thus, measuring aerosol size distribution and generation rate is important for (1) the assessment of inhalation exposures of workers, (2) the selection of respiratory protection equipment, and (3) the design of appropriate filtration systems. Size distribution of the aerosols generated during cutting of different metals by plasma torch was measured. Cutting rates of different metals, rate of generation of respirable mass, as well as the fraction of the released kerf that become respirable were determined. This report presents results of these studies. Measurements of the particles generated during cutting of metal plates with a plasma arc torch revealed the presence of particles with mass median aerodynamic diameters of particles close to 0.2 {micro}m, arising from condensation of vaporized material and subsequent rapid formation of aggregates. Particles of larger size, resulting from ejection of melted material or fragments from the cutting zone, were also observed. This study presents data regarding the metal cutting rate, particle size distribution, and their generation rate, while using different cutting tools and metals. The study shows that respirable particles constitute only a small fraction of the released kerf.

  12. Current Dosing Paradigm for Stereotactic Radiosurgery Alone After Surgical Resection of Brain Metastases Needs to Be Optimized for Improved Local Control

    SciTech Connect (OSTI)

    Prabhu, Roshan; Shu, Hui-Kuo; Hadjipanayis, Constantinos; Dhabaan, Anees; Hall, William; Raore, Bethwel; Olson, Jeffrey; Curran, Walter; Oyesiku, Nelson; Crocker, Ian

    2012-05-01

    Purpose: To describe the use of radiosurgery (RS) alone to the resection cavity after resection of brain metastases as an alternative to adjuvant whole-brain radiotherapy (WBRT). Methods and Materials: Sixty-two patients with 64 cavities were treated with linear accelerator-based RS alone to the resection cavity after surgical removal of brain metastases between March 2007 and August 2010. Fifty-two patients (81%) had a gross total resection. Median cavity volume was 8.5 cm{sup 3}. Forty-four patients (71%) had a single metastasis. Median marginal and maximum doses were 18 Gy and 20.4 Gy, respectively. Sixty-one cavities (95%) had gross tumor volume to planning target volume expansion of {>=}1 mm. Results: Six-month and 1-year actuarial local recurrence rates were 14% and 22%, respectively, with a median follow-up period of 9.7 months. Six-month and 1-year actuarial distant brain recurrence, total intracranial recurrence, and freedom from WBRT rates were 31% and 51%, 41% and 63%, and 91% and 74%, respectively. The symptomatic cavity radiation necrosis rate was 8%, with 2 patients (3%) undergoing surgery. Of the 11 local failures, 8 were in-field, 1 was marginal, and 2 were both (defined as in-field if {>=}90% of recurrence within the prescription isodose and marginal if {>=}90% outside of the prescription isodose). Conclusions: The high rate of in-field cavity failure suggests that geographic misses with highly conformal RS are not a major contributor to local recurrence. The current dosing regimen derived from Radiation Therapy Oncology Group protocol 90-05 should be optimized in this patient population before any direct comparison with WBRT.

  13. ASSESSMENT OF UNCERTAINTY IN THE RADIATION DOSES FOR THE TECHA RIVER DOSIMETRY SYSTEM

    SciTech Connect (OSTI)

    Napier, Bruce A.; Degteva, M. O.; Anspaugh, L. R.; Shagina, N. B.

    2009-10-23

    In order to provide more accurate and precise estimates of individual dose (and thus more precise estimates of radiation risk) for the members of the ETRC, a new dosimetric calculation system, the Techa River Dosimetry System-2009 (TRDS-2009) has been prepared. The deterministic version of the improved dosimetry system TRDS-2009D was basically completed in April 2009. Recent developments in evaluation of dose-response models in light of uncertain dose have highlighted the importance of different types of uncertainties in the development of individual dose estimates. These include uncertain parameters that may be either shared or unshared within the dosimetric cohort, and also the nature of the type of uncertainty as aleatory or epistemic and either classical or Berkson. This report identifies the nature of the various input parameters and calculational methods incorporated in the Techa River Dosimetry System (based on the TRDS-2009D implementation), with the intention of preparing a stochastic version to estimate the uncertainties in the dose estimates. This report reviews the equations, databases, and input parameters, and then identifies the authors interpretations of their general nature. It presents the approach selected so that the stochastic, Monte-Carlo, implementation of the dosimetry System - TRDS-2009MC - will provide useful information regarding the uncertainties of the doses.

  14. HIgh Rate X-ray Fluorescence Detector

    SciTech Connect (OSTI)

    Grudberg, Peter Matthew

    2013-04-30

    The purpose of this project was to develop a compact, modular multi-channel x-ray detector with integrated electronics. This detector, based upon emerging silicon drift detector (SDD) technology, will be capable of high data rate operation superior to the current state of the art offered by high purity germanium (HPGe) detectors, without the need for liquid nitrogen. In addition, by integrating the processing electronics inside the detector housing, the detector performance will be much less affected by the typically noisy electrical environment of a synchrotron hutch, and will also be much more compact than current systems, which can include a detector involving a large LN2 dewar and multiple racks of electronics. The combined detector/processor system is designed to match or exceed the performance and features of currently available detector systems, at a lower cost and with more ease of use due to the small size of the detector. In addition, the detector system is designed to be modular, so a small system might just have one detector module, while a larger system can have many ?? you can start with one detector module, and add more as needs grow and budget allows. The modular nature also serves to simplify repair. In large part, we were successful in achieving our goals. We did develop a very high performance, large area multi-channel SDD detector, packaged with all associated electronics, which is easy to use and requires minimal external support (a simple power supply module and a closed-loop water cooling system). However, we did fall short of some of our stated goals. We had intended to base the detector on modular, large-area detectors from Ketek GmbH in Munich, Germany; however, these were not available in a suitable time frame for this project, so we worked instead with pnDetector GmbH (also located in Munich). They were able to provide a front-end detector module with six 100 m^2 SDD detectors (two monolithic arrays of three elements each) along with associated preamplifiers; these detectors surpassed the performance we expected to get from the Ketek detectors, however they are housed in a sealed module, which does not offer the ease of repair and expandability we??d hoped to achieve with the Ketek SDD??s. Our packaging efforts were quite successful, as we came up with a very compact way to mount the detector and to house the associated electronics, as well as a very effective way to reliably take out the heat (from the electronics as well as the detector??s Peltier coolers) without risk of condensation and without external airflow or vibration, which could create problems for the target applications. While we were able to design compact processing electronics that fit into the detector assembly, they are still at the prototype stage, and would require a significant redesign to achieve product status. We have not yet tested this detector at a synchrotron facility; we do still plan on working with some close contacts at the nearby Stanford Synchrotron Radiation Laboratory (SSRL) to get some testing with the beam (using existing commercial electronics for readout, as the integrated processor is not ready for use).

  15. Applicable Interest Rates for Slice Product (contracts/slice...

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

    is the Prime Rate for Large Banks (the base rate on corporate loans posted by at least 75% of the nation's 30 largest Banks) as reported in the Wall Street Journal on the first...

  16. ENERGY STAR Webinar: ENERGY STAR and Green Building Rating Systems...

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

    ENERGY STAR and Green Building Rating Systems ENERGY STAR Webinar: ENERGY STAR and Green Building Rating Systems October 13, 2015 2:00PM to 3:00PM EDT Online Hosted by the U.S....

  17. Flag rates for deletion? | OpenEI Community

    Open Energy Info (EERE)

    some "rates" that don't belong; they are one-time connection fees instead of rates (e.g. with a 2,500 connection fee as a "fixed monthly charge"). Is there some way to flag...

  18. Construction, Qualification, and Low Rate Production Start-up...

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

    Construction, Qualification, and Low Rate Production Start-up of a DC Bus Capacitor High ... Construction, Qualification, and Low Rate Production Start-up of a DC Bus Capacitor High ...

  19. Tiered time-of-use rates | OpenEI Community

    Open Energy Info (EERE)

    Tiered time-of-use rates Home > Groups > Utility Rate Hello Last year, I found OpenEI via NREL's System Advisor Model, when I was considering a PV system for my home in PG&E's...

  20. Access Rate Control System | Y-12 National Security Complex

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

    Access Rate Control System Access Rate Control System The mp4 video format is not supported by this browser. Download video Captions: On Time: 4:03 min Developed to support...