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1

High rate 4. pi. beta. -. gamma. coincidence counting system  

SciTech Connect

A high count rate 4..pi.. ..beta..-..gamma.. coincidence counting system for the determination of absolute disintegration rates of short half-life radionuclides is described. With this system the dead time per pulse is minimized by not stretching any pulses beyond the width necessary to satisfy overlap coincidence requirements. The equations used to correct for the ..beta.., ..gamma.., and coincidence channel dead times and for accidental coincidences are presented but not rigorously developed. Experimental results are presented for a decaying source of /sup 56/Mn initially at 2 x 10/sup 6/ d/s and a set of /sup 60/Co sources of accurately known source strengths varying from 10/sup 3/ to 2 x 10/sup 6/ d/s. A check of the accidental coincidence equation for the case of two independent sources with varying source strengths is presented.

Johnson, L.O.; Gehrke, R.J.

1978-01-01T23:59:59.000Z

2

Sub-millimeter nuclear medical imaging with reduced dose application in positron emission tomography using beta-gamma coincidences  

E-Print Network (OSTI)

Positron emission tomography (PET) permits a functional understanding of the underlying causes of many diseases. Modern whole-body PET systems reach a spatial resolution of 2-6 mm (FWHM). A limitation of this technique occurs from the thermalization and diffusion of the positron before its annihilation, typically within the mm range. We present a nuclear medical imaging technique, able to reach sub-millimeter spatial resolution in 3 dimensions with a reduced effective dose application compared to conventional PET. This 'gamma-PET' technique draws on specific medical isotopes, simultaneously emitting an additional photon accompanying the beta^+ decay. Exploiting the triple coincidence between the positron annihilation and the third photon, it is possible to separate the reconstructed 'true' events from background. In order to characterize the potential of this technique, MC simulations and image reconstructions have been performed. The achievable spatial resolution has been found to reach ca. 0.4 mm (FWHM) in each direction for the visualization of a 22Na point source. Starting with a source activity of only 1.48 MBq for 89Zr, corresponding to ca. 130 - 270 times less compared to a conventional PET examination using 18F-FDG, about 40 intersections (sufficient for a reliable image reconstruction of a point source) can be identified after a typical examination time of 900 seconds. This results in a strongly reduced effective dose of, e.g., 0.785 mSv for 89Zr-cmAb-U36, compared to the applied effective dose in a typical human PET examination with 18F-FDG of about 7.5 mSv. Increasing the applied effective dose to 7.5 mSv, the examination time will be reduced to 94 s for only 14.2 MBq of 89Zr-cmAb-U36. The reduced effective dose, or, the reduced examination time, surpass the performance of a conventional PET device by more than one order of magnitude.

C. Lang; D. Habs; K. Parodi; P. G. Thirolf

2013-05-18T23:59:59.000Z

3

Sub-millimeter nuclear medical imaging with reduced dose application in positron emission tomography using beta-gamma coincidences  

E-Print Network (OSTI)

Positron emission tomography (PET) permits a functional understanding of the underlying causes of many diseases. Modern whole-body PET systems reach a spatial resolution of 2-6 mm (FWHM). A limitation of this technique occurs from the thermalization and diffusion of the positron before its annihilation, typically within the mm range. We present a nuclear medical imaging technique, able to reach sub-millimeter spatial resolution in 3 dimensions with a reduced effective dose application compared to conventional PET. This 'gamma-PET' technique draws on specific medical isotopes, simultaneously emitting an additional photon accompanying the beta^+ decay. Exploiting the triple coincidence between the positron annihilation and the third photon, it is possible to separate the reconstructed 'true' events from background. In order to characterize the potential of this technique, MC simulations and image reconstructions have been performed. The achievable spatial resolution has been found to reach ca. 0.4 mm (FWHM) in ...

Lang, C; Parodi, K; Thirolf, P G

2013-01-01T23:59:59.000Z

4

Operational dose rate visualization techniques  

SciTech Connect

The analysis of the gamma ray dose rate in the vicinity of a radiation source can be greatly aided by the use of recent state-of-the-art visualization techniques. The method involves calculating dose rates at thousands of locations within a complex geometry system. This information is then processed to create contour plots of the dose rate. Additionally, when these contour plots are created, animations can be created that dynamically display the dose rate as the shields or sources are moved.

Schwarz, R.A.; Morford, R.J.; Carter, L.L.; Jones, G.B.; Greenborg, J.

1994-01-01T23:59:59.000Z

5

Emerging Robust Beta Gamma TiAl Alloys  

Science Conference Proceedings (OSTI)

Recently a new class of TiAl based alloy system, called beta gamma, that ... Phase-Field Simulation on Phase Transformation during Creep Deformation in Type ...

6

Dose rate visualization of radioisotope thermoelectric generators  

DOE Green Energy (OSTI)

Advanced visualization techniques can be used to investigate gamma ray and neutron dose rates around complex dose rate intensive operations. A method has been developed where thousands of dose points are calculated using the MCNP(Monte Carlo N-Particle) computer code and then displayed to create color contour plots of the dose rate for complex geometries. Once these contour plots are created, they are sequenced together creating an animation to dynamically show how the dose rate changes with changes in the geometry or source over time.

Schwarz, R.A.; Kessler, S.F.; Tomaszewski, T.A.

1995-09-01T23:59:59.000Z

7

Radiation Leukemogenesis at Low Dose Rates  

SciTech Connect

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.

Weil, Michael; Ullrich, Robert

2013-09-25T23:59:59.000Z

8

Historical river flow rates for dose calculations  

Science Conference Proceedings (OSTI)

Annual average river flow rates are required input to the LADTAP Computer Code for calculating offsite doses from liquid releases of radioactive materials to the Savannah River. The source of information on annual river flow rates used in dose calculations varies, depending on whether calculations are for retrospective releases or prospective releases. Examples of these types of releases are: Retrospective - releases from routine operations (annual environmental reports) and short term release incidents that have occurred. Prospective - releases that might be expected in the future from routine or abnormal operation of existing or new facilities (EIS`s, EID`S, SAR`S, etc.). This memorandum provides historical flow rates at the downstream gauging station at Highway 301 for use in retrospective dose calculations and derives flow rate data for the Beaufort-Jasper and Port Wentworth water treatment plants.

Carlton, W.H.

1991-06-10T23:59:59.000Z

9

An alpha/beta/gamma health physics instrument with pulse-shape discrimination  

SciTech Connect

A recent breakthrough in alpha scintillation detector design supports the feasibility of extending this new technology to the development of a monolithic alpha/beta/gamma ({alpha}/{beta}/{gamma}) scintillation detector. The new scintillator is physically robust and chemically resistant to environmental conditions encountered in radiation monitoring, and yet inexpensive to manufacture. The use of pulse-shape discrimination electronics allows pulses from each scintillator to be separated for particle identification. An {alpha}/{beta}/{gamma} detector has a wide variety of possible applications including laundry monitoring, wastewater monitoring, air sampling, and health physics instrumentation. 2 refs., 1 fig.

McElhaney, S.A.; Chiles, M.M.; Ramsey, J.A.

1990-01-01T23:59:59.000Z

10

Development of a Low Dose Rate Irradiation Facility for Long...  

NLE Websites -- All DOE Office Websites (Extended Search)

Low Dose Rate Irradiation Facility for Long Term Animal Exposures at Colorado State University Michael Weil Colorado State University Abstract A low dose rate irradiation facility...

11

Estimating Dose Rates from Activated Groundwater at Accelerator Sites  

Science Conference Proceedings (OSTI)

Dose/Dose Rate / Special Issue on the 11th International Conference on Radiation Shielding and the 15th Topical Meeting of the Radiation Protection and Shielding Division (PART 3) / Radiation Protection

N. Prolingheuer; M. Herbst; B. Heuel-Fabianek; R. Moormann; R. Nabbi; B. Schlögl; J. Vanderborght

12

High Dose-Rate Versus Low Dose-Rate Brachytherapy for Lip Cancer  

Science Conference Proceedings (OSTI)

Purpose: To analyze the outcome after low-dose-rate (LDR) or high-dose-rate (HDR) brachytherapy for lip cancer. Methods and Materials: One hundred and three patients with newly diagnosed squamous cell carcinoma of the lip were treated between March 1985 and June 2009 either by HDR (n = 33) or LDR brachytherapy (n = 70). Sixty-eight patients received brachytherapy alone, and 35 received tumor excision followed by brachytherapy because of positive resection margins. Acute and late toxicity was assessed according to the Common Terminology Criteria for Adverse Events 3.0. Results: Median follow-up was 3.1 years (range, 0.3-23 years). Clinical and pathological variables did not differ significantly between groups. At 5 years, local recurrence-free survival, regional recurrence-free survival, and overall survival rates were 93%, 90%, and 77%. There was no significant difference for these endpoints when HDR was compared with LDR brachytherapy. Forty-two of 103 patients (41%) experienced acute Grade 2 and 57 of 103 patients (55%) experienced acute Grade 3 toxicity. Late Grade 1 toxicity was experienced by 34 of 103 patients (33%), and 5 of 103 patients (5%) experienced late Grade 2 toxicity; no Grade 3 late toxicity was observed. Acute and late toxicity rates were not significantly different between HDR and LDR brachytherapy. Conclusions: As treatment for lip cancer, HDR and LDR brachytherapy have comparable locoregional control and acute and late toxicity rates. HDR brachytherapy for lip cancer seems to be an effective treatment with acceptable toxicity.

Ghadjar, Pirus, E-mail: pirus.ghadjar@insel.ch [Department of Radiation Oncology, Inselspital, Bern University Hospital, and University of Bern (Switzerland); Bojaxhiu, Beat [Department of Radiation Oncology, Inselspital, Bern University Hospital, and University of Bern (Switzerland); Simcock, Mathew [Swiss Group for Clinical Cancer Research Coordinating Center, Bern (Switzerland); Terribilini, Dario; Isaak, Bernhard [Division of Medical Radiation Physics, Inselspital, Bern University Hospital, and University of Bern, Bern (Switzerland); Gut, Philipp; Wolfensberger, Patrick; Broemme, Jens O.; Geretschlaeger, Andreas; Behrensmeier, Frank; Pica, Alessia; Aebersold, Daniel M. [Department of Radiation Oncology, Inselspital, Bern University Hospital, and University of Bern (Switzerland)

2012-07-15T23:59:59.000Z

13

Forecasting the Dose and Dose Rate from a Solar Particle Event Using Localized Weighted Regression  

Science Conference Proceedings (OSTI)

Dose/Dose Rate / Special Issue on the 11th International Conference on Radiation Shielding and the 15th Topical Meeting of the Radiation Protection and Shielding Division (Part 1) / Radiation Protection

T. F. Nichols; L. W. Townsend; J. W. Hines

14

The status of low dose rate and future of high dose rate Cf-252 brachytherapy  

Science Conference Proceedings (OSTI)

This work describes the current status of the US low dose rate (LDR) Cf-252 brachytherapy program. The efforts undertaken towards development of a high dose rate (HDR) remotely after loaded Cf-252 source, which can accommodate 1 mg or greater Cf-252, are also described. This HDR effort is a collaboration between Oak Ridge National Laboratory (ORNL), commercial remote after loader manufactures, the Gershenson Radiation Oncology Center (ROC), and Wayne State University. To achieve this goal, several advances in isotope chemistry and source preparation at ORNL must be achieved to yield a specific material source loading of greater than or equal 1 mg Cf-252 per mm3. Development work with both radioactive and non-radioactive stand-ins for Cf-252 have indicated the feasibility of fabricating such sources. As a result, the decreased catheter diameter and computer controlled source placement will permit additional sites (e.g. brain, breast, prostate, lung, parotid, etc.) to be treated effectively with Cf-252 sources. Additional work at the Radiochemical Engineering and Development Center (REDC) remains in source fabrication, after loader modification, and safe design. The current LDR Cf-252 Treatment Suite at the ROC is shielded and licensed to hold up to 1 mg of Cf-252. This was designed to maintain cumulative personnel exposure, both external to the room and in direct isotope handling, at less than 20 microSv/hr. However, cumulative exposure may be greatly decreased if a Cf-252 HDR unit is employed which would eliminate direct isotope handling and decrease treatment times from tilde 3 hours to an expected range of 3 to 15 minutes. Such a Cf-252 HDR source will also demonstrate improved dose distributions over current LDR treatments due to the ability to step the point-like source throughout the target volume and weight the dwell time accordingly.

Rivard, M.J.; Wierzbicki, J.G.; Van den Heuvel, F.; Chuba, P.J.; Fontanesi, J. [Wayne State Univ., Detroit, MI (United States). Dept. of Radiation Oncology; Martin, R.C.; McMahon, R.R.; Haire, R.G. [Oak Ridge National Lab., TN (United States)

1997-12-01T23:59:59.000Z

15

External dose-rate conversion factors for calculation of dose to the public  

SciTech Connect

This report presents a tabulation of dose-rate conversion factors for external exposure to photons and electrons emitted by radionuclides in the environment. This report was prepared in conjunction with criteria for limiting dose equivalents to members of the public from operations of the US Department of Energy (DOE). The dose-rate conversion factors are provided for use by the DOE and its contractors in performing calculations of external dose equivalents to members of the public. The dose-rate conversion factors for external exposure to photons and electrons presented in this report are based on a methodology developed at Oak Ridge National Laboratory. However, some adjustments of the previously documented methodology have been made in obtaining the dose-rate conversion factors in this report. 42 refs., 1 fig., 4 tabs.

Not Available

1988-07-01T23:59:59.000Z

16

Low-Dose/Dose-Rate Low-LET Radiation Protects Us from Cancer  

NLE Websites -- All DOE Office Websites (Extended Search)

Dose/Dose-Rate Low-LET Radiation Protects Us from Cancer Dose/Dose-Rate Low-LET Radiation Protects Us from Cancer Bobby R. Scott, Ph.D. and Jennifer D. Di Palma Lovelace Respiratory Research Institute, 2425 Ridgecrest Drive SE Albuquerque, NM 87108 USA Life on earth evolved in a low-level ionizing radiation environment comprised of terrestrial radiation and cosmic rays. Today we all reside in an ionizing radiation environment comprised of both natural background radiation and radiation from human activities (e.g., Chernobyl accident). An evolutionary benefit of the interaction of low-level, low linear-energy-transfer (LET) ionizing radiation with mammalian life forms on earth is adapted protection. Adapted protection involves low-dose/dose-rate, low-LET radiation induced high-fidelity DNA repair in cooperation with normal apoptosis (presumed p53

17

PRECEDENTS FOR AUTHORIZATION OF CONTENTS USING DOSE RATE MEASUREMENTS  

SciTech Connect

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.

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

2012-06-05T23:59:59.000Z

18

Advanced Computational Approaches for Characterizing Stochastic Cellular Responses to Low Dose, Low Dose Rate Exposures  

SciTech Connect

OAK - B135 This project final report summarizes modeling research conducted in the U.S. Department of Energy (DOE), Low Dose Radiation Research Program at the Lovelace Respiratory Research Institute from October 1998 through June 2003. The modeling research described involves critically evaluating the validity of the linear nonthreshold (LNT) risk model as it relates to stochastic effects induced in cells by low doses of ionizing radiation and genotoxic chemicals. The LNT model plays a central role in low-dose risk assessment for humans. With the LNT model, any radiation (or genotoxic chemical) exposure is assumed to increase one¡¯s risk of cancer. Based on the LNT model, others have predicted tens of thousands of cancer deaths related to environmental exposure to radioactive material from nuclear accidents (e.g., Chernobyl) and fallout from nuclear weapons testing. Our research has focused on developing biologically based models that explain the shape of dose-response curves for low-dose radiation and genotoxic chemical-induced stochastic effects in cells. Understanding the shape of the dose-response curve for radiation and genotoxic chemical-induced stochastic effects in cells helps to better understand the shape of the dose-response curve for cancer induction in humans. We have used a modeling approach that facilitated model revisions over time, allowing for timely incorporation of new knowledge gained related to the biological basis for low-dose-induced stochastic effects in cells. Both deleterious (e.g., genomic instability, mutations, and neoplastic transformation) and protective (e.g., DNA repair and apoptosis) effects have been included in our modeling. Our most advanced model, NEOTRANS2, involves differing levels of genomic instability. Persistent genomic instability is presumed to be associated with nonspecific, nonlethal mutations and to increase both the risk for neoplastic transformation and for cancer occurrence. Our research results, based on applications of NEOTRANS2, indicate that nonlinear threshold-type, dose-response relationships for excess stochastic effects (problematic nonlethal mutations, neoplastic transformation) should be expected after exposure to low linear energy transfer (LET) gamma rays or gamma rays in combination with high-LET alpha radiation. Similar thresholds are expected for low-dose-rate low-LET beta irradiation. We attribute the thresholds to low-dose, low-LET radiation induced protection against spontaneous mutations and neoplastic transformations. The protection is presumed mainly to involve selective elimination of problematic cells via apoptosis. Low-dose, low-LET radiation is presumed to trigger wide-area cell signaling, which in turn leads to problematic bystander cells (e.g., mutants, neoplastically transformed cells) selectively undergoing apoptosis. Thus, this protective bystander effect leads to selective elimination of problematic cells (a tissue cleansing process in vivo). However, this protective bystander effects is a different process from low-dose stimulation of the immune system. Low-dose, low-LET radiation stimulation of the immune system may explain why thresholds for inducing excess cancer appear much larger (possibly more than 100-fold larger) than thresholds for inducing excess mutations and neoplastic transformations, when the dose rate is low. For ionizing radiation, the current risk assessment paradigm is such that the relative risk (RR) is always ¡Ý 1, no matter how small the dose. Our research results indicate that for low-dose or low-dose-rate, low-LET irradiation, RR < 1 may be more the rule than the exception. Directly tied to the current RR paradigm are the billion-dollar cleanup costs for radionuclide-contaminated DOE sites. Our research results suggest that continued use of the current RR paradigm for which RR ¡Ý 1 could cause more harm than benefit to society (e.g., by spreading unwarranted fear about phantom excess risks associated with low-dose low-LET radiation). Such phantom risks also may arise from risk assessments conducted for com

Scott, Bobby, R., Ph.D.

2003-06-27T23:59:59.000Z

19

Advanced Computational Approaches for Characterizing Stochastic Cellular Responses to Low Dose, Low Dose Rate Exposures  

Science Conference Proceedings (OSTI)

OAK - B135 This project final report summarizes modeling research conducted in the U.S. Department of Energy (DOE), Low Dose Radiation Research Program at the Lovelace Respiratory Research Institute from October 1998 through June 2003. The modeling research described involves critically evaluating the validity of the linear nonthreshold (LNT) risk model as it relates to stochastic effects induced in cells by low doses of ionizing radiation and genotoxic chemicals. The LNT model plays a central role in low-dose risk assessment for humans. With the LNT model, any radiation (or genotoxic chemical) exposure is assumed to increase one¡¯s risk of cancer. Based on the LNT model, others have predicted tens of thousands of cancer deaths related to environmental exposure to radioactive material from nuclear accidents (e.g., Chernobyl) and fallout from nuclear weapons testing. Our research has focused on developing biologically based models that explain the shape of dose-response curves for low-dose radiation and genotoxic chemical-induced stochastic effects in cells. Understanding the shape of the dose-response curve for radiation and genotoxic chemical-induced stochastic effects in cells helps to better understand the shape of the dose-response curve for cancer induction in humans. We have used a modeling approach that facilitated model revisions over time, allowing for timely incorporation of new knowledge gained related to the biological basis for low-dose-induced stochastic effects in cells. Both deleterious (e.g., genomic instability, mutations, and neoplastic transformation) and protective (e.g., DNA repair and apoptosis) effects have been included in our modeling. Our most advanced model, NEOTRANS2, involves differing levels of genomic instability. Persistent genomic instability is presumed to be associated with nonspecific, nonlethal mutations and to increase both the risk for neoplastic transformation and for cancer occurrence. Our research results, based on applications of NEOTRANS2, indicate that nonlinear threshold-type, dose-response relationships for excess stochastic effects (problematic nonlethal mutations, neoplastic transformation) should be expected after exposure to low linear energy transfer (LET) gamma rays or gamma rays in combination with high-LET alpha radiation. Similar thresholds are expected for low-dose-rate low-LET beta irradiation. We attribute the thresholds to low-dose, low-LET radiation induced protection against spontaneous mutations and neoplastic transformations. The protection is presumed mainly to involve selective elimination of problematic cells via apoptosis. Low-dose, low-LET radiation is presumed to trigger wide-area cell signaling, which in turn leads to problematic bystander cells (e.g., mutants, neoplastically transformed cells) selectively undergoing apoptosis. Thus, this protective bystander effect leads to selective elimination of problematic cells (a tissue cleansing process in vivo). However, this protective bystander effects is a different process from low-dose stimulation of the immune system. Low-dose, low-LET radiation stimulation of the immune system may explain why thresholds for inducing excess cancer appear much larger (possibly more than 100-fold larger) than thresholds for inducing excess mutations and neoplastic transformations, when the dose rate is low. For ionizing radiation, the current risk assessment paradigm is such that the relative risk (RR) is always ¡Ý 1, no matter how small the dose. Our research results indicate that for low-dose or low-dose-rate, low-LET irradiation, RR fear about phantom excess risks associated with low-dose low-LET radiation). Such phantom risks also may arise from risk assessments conducted for com

Scott, Bobby, R., Ph.D.

2003-06-27T23:59:59.000Z

20

Beta-Gamma Coincidence Counting Using an Yttrium Aluminum Perovskit and Bismuth Germanate Phoswich Scintillator  

SciTech Connect

Abstract– Phoswich detectors (two scintillators attached to the same photomultiplier-tube) have been used in the past to measure either betas or gammas separately but were not used to measure beta-gamma coincidence signatures. These coincidence signatures are very important for the detection of many fission products and are exploited to detect four radioxenon isotopes using the Automated Radioxenon Sampler/Analyzer (ARSA) [1]. Previous PNNL work with a phoswich detector used a commercially available, thin disk of scintillating CaF2(Eu) and a 2” thick NaI(Tl) crystal in a phoswich arrangement. Studies with this detector measured the beta-gamma coincidence signatures from 133Xe, 214Pb and 214Bi [2]. This scintillator combination worked but was not a good match in scintillation light decay times, 940-ns for CaF2(Eu) and 230 ns for NaI(Tl). Additionally, a 6 mm thick quartz window was placed between the NaI(Tl) and the CaF2 to ensure a hermetic seal for the NaI(Tl) crystal . This dead layer significantly reduced the detection probability of the low energy x-rays and gammas that are part of the coincidence signatures for 214Pb, 214Bi and the radioxenons. Further research showed that Yttrium aluminum perovskit (YAP) and bismuth germanate (BGO) have very good scintillation light characteristics and no hermetic seal requirements. The 27-ns scintillation light decay time of YAP and the 300-ns decay time for BGO are a good match between fast and slow light output. The scintillation light output was measured using XIATM digital signal processing readout electronics, and the fast (YAP) and slow (BGO) light components allowed discrimination between the beta and gamma contributions of the radioactive decays. In this paper we discuss the experimental setup and results obtained with this new phoswich detector and the applications beyond radioxenon gas measurements.

McIntyre, Justin I.; Schrom, Brian T.; Aalseth, Craig E.; Cooper, Matthew W.; Hayes, James C.; Heimbigner, Tom R.; Hossbach, Todd W.; Hubbard, Charles W.; Litke, Kevin E.; Ripplinger, Mike D.; Seifert, Carolyn E.; Suarez, Reynold

2006-02-27T23:59:59.000Z

Note: This page contains sample records for the topic "beta-gamma dose rates" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

The Dose Rate Conversion Factors for Nuclear Fallout  

SciTech Connect

In a previous paper, the composite exposure rate conversion factor (ECF) for nuclear fallout was calculated using a simple theoretical photon-transport model. The theoretical model was used to fill in the gaps in the FGR-12 table generated by ORNL. The FGR-12 table contains the individual conversion factors for approximate 1000 radionuclides. However, in order to calculate the exposure rate during the first 30 minutes following a nuclear detonation, the conversion factors for approximately 2000 radionuclides are needed. From a human-effects standpoint, it is also necessary to have the dose rate conversion factors (DCFs) for all 2000 radionuclides. The DCFs are used to predict the whole-body dose rates that would occur if a human were standing in a radiation field of known exposure rate. As calculated by ORNL, the whole-body dose rate (rem/hr) is approximately 70% of the exposure rate (R/hr) at one meter above the surface. Hence, the individual DCFs could be estimated by multiplying the individual ECFs by 0.7. Although this is a handy rule-of-thumb, a more consistent (and perhaps, more accurate) method of estimating the individual DCFs for the missing radionuclides in the FGR-12 table is to use the linear relationship between DCF and total gamma energy released per decay. This relationship is shown in Figure 1. The DCFs for individual organs in the body can also be estimated from the estimated whole-body DCF. Using the DCFs given FGR-12, the ratio of the organ-specific DCFs to the whole-body DCF were plotted as a function of the whole-body DCF. From these plots, the asymptotic ratios were obtained (see Table 1). Using these asymptotic ratios, the organ-specific DCFs can be estimated using the estimated whole-body DCF for each of the missing radionuclides in the FGR-12 table. Although this procedure for estimating the organ-specific DCFs may over-estimate the value for some low gamma-energy emitters, having a finite value for the organ-specific DCFs in the table is probably better than having no value at all. A summary of the complete ECF and DCF values are given in Table 2.

Spriggs, G D

2009-02-13T23:59:59.000Z

22

Radiation dose-rate meter using an energy-sensitive counter  

DOE Patents (OSTI)

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. 3 figs.

Kopp, M.K.

1986-12-17T23:59:59.000Z

23

Radiation dose-rate meter using an energy-sensitive counter  

DOE Patents (OSTI)

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.

Kopp, Manfred K. (Oak Ridge, TN)

1988-01-01T23:59:59.000Z

24

DEVELOPMENT AND CHARACTERIZATION OF A NOVEL VARIABLE LOW DOSE-RATE IRRADIATOR FOR IN VIVO  

E-Print Network (OSTI)

the atomic bomb Life Span Study (LSS) cohort. However, the total doses and dose rates in the LSS cohort (1973) report that for Chinese hamster ovary cells, toxicity is reduced by several orders of magnitude dose rate is lowered further and further, some investigators report an inverse dose-rate effect

Engelward, Bevin

25

The proceedings of a symposium on dose rate in mammalian radiation biology, April 29 - May 1, 1968  

SciTech Connect

MAMMALIA. Radiation effects on, effects of dose rate on; RADIOBIOLOGY. Conference on effects of dose rate on radiosensitivity of mammals.

Brown, D.G.; Cragle, R.G.; Noonan, T.R. (eds.)

1968-01-01T23:59:59.000Z

26

Adaptive Responses to Low Dose/Low Dose-Rate γ-Rays in Normal Human Fibroblasts:  

NLE Websites -- All DOE Office Websites (Extended Search)

Responses to Low Dose/Low Dose-Rate γ-Rays in Normal Human Fibroblasts: Responses to Low Dose/Low Dose-Rate γ-Rays in Normal Human Fibroblasts: The Role of Oxidative Metabolism Edouard I. Azzam 1 , Sonia M. de Toledo 1 , Badri N. Pandey 1 , Perumal Venkatachalam 1 , Manuela Buoannano 1 , Zhi Yang 1 , Ling Li 3 , Donna M. Gordon 2 , Roger W. Howell 1 , Debkumar Pain 2 and Douglas R. Spitz 3 1 Department of Radiology, 2 Department of Pharmacology and Physiology, UMDNJ-New Jersey Medical School, Newark, NJ 3 Free Radical and Radiation Biology Program, University of Iowa, Iowa City, IA To investigate low dose/low dose-rate effects of low linear energy transfer ionizing radiation, we used γ-irradiated cells adapted to grow in three-dimensional architecture that mimics cell growth in vivo. We determined cellular, molecular and biochemical changes in these

27

Irradiators for measuring the biological effects of low dose-rate ionizing radiation fields  

E-Print Network (OSTI)

Biological response to ionizing radiation differs with radiation field. Particle type, energy spectrum, and dose-rate all affect biological response per unit dose. This thesis describes methods of spectral analysis, ...

Davidson, Matthew Allen

2011-01-01T23:59:59.000Z

28

Dose-rate conversion factors for external exposure to photons and electrons  

SciTech Connect

Dose-rate conversion factors for external exposure to photons and electrons have been calculated for approximately 500 radionuclides of potential importance in environmental radiological assessments. The dose-rate factors were obtained using the DOSFACTER computer code. The results given in this report incorporate calculation of electron dose-rate factors for radiosensitive tissues of the skin, improved estimates of organ dose-rate factors for photons, based on organ doses for monoenergetic sources at the body surface of an exposed individual, and the spectra of scattered photons in air from monoenergetic sources in an infinite, uniformly contaminated atmospheric cloud, calculation of dose-rate factors for other radionuclides in addition to those of interest in the nuclear fuel cycle, and incorporation of updated radioactive decay data for all radionuclides. Dose-rate factors are calculated for three exposure modes - immersion in contaminated air, immersion in contaminated water, and exposure at a height of 1 m above a contaminated ground surface. The report presents the equations used to calculate the external dose-rate factors for photons and electrons, documentation of the revised DOSFACTER computer code, and a complete tabulation of the calculated dose-rate factors. 30 refs., 12 figs.

Kocher, D.C.

1981-08-01T23:59:59.000Z

29

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

SciTech Connect

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.

Reynoso Mejia, C. A.; Buenfil Burgos, A. E.; Ruiz Trejo, C. [Instituto de Fisica, Universidad Nacional Autonoma de Mexico, A.P. 20-364, 01000, Mexico D.F. (Mexico); Mota Garcia, A.; Trejo Duran, E.; Rodriguez Ponce, M. [Instituto Nacional de Cancerologia, Av. San Fernando 22, Tlalpan, 4080, Mexico D.F. (Mexico); Gamboa de Buen, I. [Instituto de Ciencias Nucleares, Universidad Nacional Autonoma de Mexico, A.P. 70-543, 04510, Mexico D.F. (Mexico)

2010-12-07T23:59:59.000Z

30

Impact of the Revised 10 CFR 835 on the Neutron Dose Rates at LLNL  

SciTech Connect

In June 2007, 10 CFR 835 [1] was revised to include new radiation weighting factors for neutrons, updated dosimetric models, and dose terms consistent with the newer ICRP recommendations. A significant aspect of the revised 10 CFR 835 is the adoption of the recommendations outlined in ICRP-60 [2]. The recommended new quantities demand a review of much of the basic data used in protection against exposure to sources of ionizing radiation. The International Commission on Radiation Units and Measurements has defined a number of quantities for use in personnel and area monitoring [3,4,5] including the ambient dose equivalent H*(d) to be used for area monitoring and instrument calibrations. These quantities are used in ICRP-60 and ICRP-74. This report deals only with the changes in the ambient dose equivalent and ambient dose rate equivalent for neutrons as a result of the implementation of the revised 10 CFR 835. In the report, the terms neutron dose and neutron dose rate will be used for convenience for ambient neutron dose and ambient neutron dose rate unless otherwise stated. This report provides a qualitative and quantitative estimate of how much the neutron dose rates at LLNL will change with the implementation of the revised 10 CFR 835. Neutron spectra and dose rates from selected locations at the LLNL were measured with a high resolution spectroscopic neutron dose rate system (ROSPEC) as well as with a standard neutron rem meter (a.k.a., a remball). The spectra obtained at these locations compare well with the spectra from the Radiation Calibration Laboratory's (RCL) bare californium source that is currently used to calibrate neutron dose rate instruments. The measurements obtained from the high resolution neutron spectrometer and dose meter ROSPEC and the NRD dose meter compare within the range of {+-}25%. When the new radiation weighting factors are adopted with the implementation of the revised 10 CFR 835, the measured dose rates will increase by up to 22%. The health physicists should consider this increase for any areas that have dose rates near a posting limit, such as near the 100 mrem/hr for a high radiation area, as this increase in measured dose rate may result in some changes to postings and consequent radiological controls.

Radev, R

2009-01-13T23:59:59.000Z

31

Dose rate dependence for different dosimeters and detectors: TLD, OSL, EBT films, and diamond detectors  

Science Conference Proceedings (OSTI)

Purpose: The use of laser accelerators in radiation therapy can perhaps increase the low number of proton and ion therapy facilities in some years due to the low investment costs and small size. The laser-based acceleration technology leads to a very high peak dose rate of about 10{sup 11} Gy/s. A first dosimetric task is the evaluation of dose rate dependence of clinical dosimeters and other detectors. Methods: The measurements were done at ELBE, a superconductive linear electron accelerator which generates electron pulses with 5 ps length at 20 MeV. The different dose rates are reached by adjusting the number of electrons in one beam pulse. Three clinical dosimeters (TLD, OSL, and EBT radiochromic films) were irradiated with four different dose rates and nearly the same dose. A faraday cup, an integrating current transformer, and an ionization chamber were used to control the particle flux on the dosimeters. Furthermore two diamond detectors were tested. Results: The dosimeters are dose rate independent up to 410{sup 9} Gy/s within 2% (OSL and TLD) and up to 1510{sup 9} Gy/s within 5% (EBT films). The diamond detectors show strong dose rate dependence. Conclusions: TLD, OSL dosimeters, and EBT films are suitable for pulsed beams with a very high pulse dose rate like laser accelerated particle beams.

Karsch, L.; Beyreuther, E.; Burris-Mog, T.; Kraft, S.; Richter, C.; Zeil, K.; Pawelke, J. [OncoRay-National Center for Radiation Research in Oncology, Technische Universitaet Dresden, Fetscherstr, 74, 01307 Dresden (Germany); Helmholtz-Zentrum Dresden-Rossendorf, Institute of Radiation Physics, P.O. Box 510119, 01314 Dresden (Germany); OncoRay-National Center for Radiation Research in Oncology, Technische Universitaet Dresden, Fetscherstr, 74, 01307 Dresden (Germany) and Helmholtz-Zentrum Dresden-Rossendorf, Institute of Radiation Physics, P.O. Box 510119, 01314 Dresden (Germany)

2012-05-15T23:59:59.000Z

32

Treatment Outcome of Medium-Dose-Rate Intracavitary Brachytherapy for Carcinoma of the Uterine Cervix: Comparison With Low-Dose-Rate Intracavitary Brachytherapy  

SciTech Connect

Purpose: To evaluate and compare the efficacy of medium-dose-rate (MDR) and low-dose-rate (LDR) intracavitary brachytherapy (ICBT) for uterine cervical cancer. Methods and Materials: We evaluated 419 patients with squamous cell carcinoma of the cervix who were treated by radical radiotherapy with curative intent at Tokyo Women's Medical University from 1969 to 1999. LDR was used from 1969 to 1986, and MDR has been used since July 1987. When compared with LDR, fraction dose was decreased and fraction size was increased (1 or 2 fractions) for MDR to make the total dose of MDR equal to that of LDR. In general, the patients received a total dose of 60 to 70 Gy at Point A with external beam radiotherapy combined with brachytherapy according to the International Federation of Gynecology and Obstetrics stage. In the LDR group, 32 patients had Stage I disease, 81 had Stage II, 182 had Stage III, and 29 had Stage IVA; in the MDR group, 9 patients had Stage I disease, 19 had Stage II, 55 had Stage III, and 12 had Stage IVA. Results: The 5-year overall survival rates for Stages I, II, III, and IVA in the LDR group were 78%, 72%, 55%, and 34%, respectively. In the MDR group, the 5-year overall survival rates were 100%, 68%, 52%, and 42%, respectively. No significant statistical differences were seen between the two groups. The actuarial rates of late complications Grade 2 or greater at 5 years for the rectum, bladder, and small intestine in the LDR group were 11.1%, 5.8%, and 2.0%, respectively. The rates for the MDR group were 11.7%, 4.2%, and 2.6%, respectively, all of which were without statistical differences. Conclusion: These data suggest that MDR ICBT is effective, useful, and equally as good as LDR ICBT in daytime (about 5 hours) treatments of patients with cervical cancer.

Kaneyasu, Yuko, E-mail: kaneyasu@hiroshima-u.ac.jp [Department of Radiation Oncology, Graduate School of Biomedical Sciences, Hiroshima University, Hiroshima (Japan) [Department of Radiation Oncology, Graduate School of Biomedical Sciences, Hiroshima University, Hiroshima (Japan); Department of Radiation Oncology, Tokyo Women's Medical University, Tokyo (Japan); Kita, Midori [Department of Radiation Oncology, Tokyo Women's Medical University, Tokyo (Japan) [Department of Radiation Oncology, Tokyo Women's Medical University, Tokyo (Japan); Department of Clinical Radiology, Tokyo Metropolitan Tama Medical Center, Tokyo (Japan); Okawa, Tomohiko [Evaluation and Promotion Center, Utsunomiya Memorial Hospital, Tochigi (Japan)] [Evaluation and Promotion Center, Utsunomiya Memorial Hospital, Tochigi (Japan); Maebayashi, Katsuya [Department of Radiation Oncology, Tokyo Women's Medical University, Tokyo (Japan)] [Department of Radiation Oncology, Tokyo Women's Medical University, Tokyo (Japan); Kohno, Mari [Department of Diagnostic Imaging and Nuclear Medicine, Tokyo Women's Medical University Hospital, Tokyo (Japan)] [Department of Diagnostic Imaging and Nuclear Medicine, Tokyo Women's Medical University Hospital, Tokyo (Japan); Sonoda, Tatsuo; Hirabayashi, Hisae [Department of Radiology, Tokyo Women's Medical University Hospital, Tokyo (Japan)] [Department of Radiology, Tokyo Women's Medical University Hospital, Tokyo (Japan); Nagata, Yasushi [Department of Radiation Oncology, Graduate School of Biomedical Sciences, Hiroshima University, Hiroshima (Japan)] [Department of Radiation Oncology, Graduate School of Biomedical Sciences, Hiroshima University, Hiroshima (Japan); Mitsuhashi, Norio [Department of Radiation Oncology, Tokyo Women's Medical University, Tokyo (Japan)] [Department of Radiation Oncology, Tokyo Women's Medical University, Tokyo (Japan)

2012-09-01T23:59:59.000Z

33

Development and characterization of a novel variable low-dose rate irradiator for in vivo mouse studies  

E-Print Network (OSTI)

Radiation exposure of humans generally results in low doses delivered at low dose rate. Our limited knowledge of the biological effects of low dose radiation is mainly based on data from the atomic bomb Life Span Study ...

Davidson, Matthew Allen

34

Dose rates from induced activity in the ELMO Bumpy Torus proof-of-principle device  

DOE Green Energy (OSTI)

Calculated results of the dose rates from induced activity in the enclosure of the ELMO Bumpy Torus proof-of-principle device (EBT-P) are presented. A cylindrical model of EBT-P is used. EBT-P will have a hydrogen plasma and thus the plasma will not produce neutrons, but substantial numbers of photoneutrons will be produced and it is the induced activity from these photoneutrons that is considered. The activation dose rates are presented for a variety of operating times and times after shutdown. Dose rates about 5 to 10 mrem/h at 1 h after shutdown are obtained and the major contributor to the dose rate at 1 h after shutdown is found to be /sup 24/Na (half-life=15.0 h).

Alsmiller, R.G.; Barish, J.; Barnes, J.M.; Santoro, R.T.

1983-11-01T23:59:59.000Z

35

Impact of Chemical Injections on Boiling Water Reactor Dose Rates: Interim Report  

Science Conference Proceedings (OSTI)

This report investigates the effects of Boiling Water Reactor (BWR) chemistry parameters on radiation field generation, with a focus on the higher reactor water Co-60 activity levels observed at plants using On-line NobleChem™ (OLNC) injections. Correlation and response curves were developed to relate reactor water and feedwater chemistry to dose rates, with the goal of improving reactor recirculation system (RRS) piping shutdown dose rate ...

2012-12-21T23:59:59.000Z

36

Calculation of the dose rate and air ionisation from radioactive fallout deposited at Chilton, Oxon (1951 to 1977)  

E-Print Network (OSTI)

Calculation of the dose rate and air ionisation from radioactive fallout deposited at Chilton, Oxon (1951 to 1977)

Gibson, J A B

1978-01-01T23:59:59.000Z

37

Nuclear mass inventory, photon dose rate and thermal decay heat of spent research reactor fuel assemblies  

SciTech Connect

As part of the Department of Energy`s spent nuclear fuel acceptance criteria, the mass of uranium and transuranic elements in spent research reactor fuel must be specified. These data are, however, not always known or readily determined. It is the purpose of this report to provide estimates of these data for some of the more common research reactor fuel assembly types. The specific types considered here are MTR, TRIGA and DIDO fuel assemblies. The degree of physical protection given to spent fuel assemblies is largely dependent upon the photon dose rate of the spent fuel material. These data also, are not always known or readily determined. Because of a self-protecting dose rate level of radiation (dose rate greater than 100 ren-x/h at I m in air), it is important to know the dose rate of spent fuel assemblies at all time. Estimates of the photon dose rate for spent MTR, TRIGA and DIDO-type fuel assemblies are given in this report.

Pond, R.B.; Matos, J.E.

1996-05-01T23:59:59.000Z

38

Statistical variability and confidence intervals for planar dose QA pass rates  

Science Conference Proceedings (OSTI)

Purpose: The most common metric for comparing measured to calculated dose, such as for pretreatment quality assurance of intensity-modulated photon fields, is a pass rate (%) generated using percent difference (%Diff), distance-to-agreement (DTA), or some combination of the two (e.g., gamma evaluation). For many dosimeters, the grid of analyzed points corresponds to an array with a low areal density of point detectors. In these cases, the pass rates for any given comparison criteria are not absolute but exhibit statistical variability that is a function, in part, on the detector sampling geometry. In this work, the authors analyze the statistics of various methods commonly used to calculate pass rates and propose methods for establishing confidence intervals for pass rates obtained with low-density arrays. Methods: Dose planes were acquired for 25 prostate and 79 head and neck intensity-modulated fields via diode array and electronic portal imaging device (EPID), and matching calculated dose planes were created via a commercial treatment planning system. Pass rates for each dose plane pair (both centered to the beam central axis) were calculated with several common comparison methods: %Diff/DTA composite analysis and gamma evaluation, using absolute dose comparison with both local and global normalization. Specialized software was designed to selectively sample the measured EPID response (very high data density) down to discrete points to simulate low-density measurements. The software was used to realign the simulated detector grid at many simulated positions with respect to the beam central axis, thereby altering the low-density sampled grid. Simulations were repeated with 100 positional iterations using a 1 detector/cm{sup 2} uniform grid, a 2 detector/cm{sup 2} uniform grid, and similar random detector grids. For each simulation, %/DTA composite pass rates were calculated with various %Diff/DTA criteria and for both local and global %Diff normalization techniques. Results: For the prostate and head/neck cases studied, the pass rates obtained with gamma analysis of high density dose planes were 2%-5% higher than respective %/DTA composite analysis on average (ranging as high as 11%), depending on tolerances and normalization. Meanwhile, the pass rates obtained via local normalization were 2%-12% lower than with global maximum normalization on average (ranging as high as 27%), depending on tolerances and calculation method. Repositioning of simulated low-density sampled grids leads to a distribution of possible pass rates for each measured/calculated dose plane pair. These distributions can be predicted using a binomial distribution in order to establish confidence intervals that depend largely on the sampling density and the observed pass rate (i.e., the degree of difference between measured and calculated dose). These results can be extended to apply to 3D arrays of detectors, as well. Conclusions: Dose plane QA analysis can be greatly affected by choice of calculation metric and user-defined parameters, and so all pass rates should be reported with a complete description of calculation method. Pass rates for low-density arrays are subject to statistical uncertainty (vs. the high-density pass rate), but these sampling errors can be modeled using statistical confidence intervals derived from the sampled pass rate and detector density. Thus, pass rates for low-density array measurements should be accompanied by a confidence interval indicating the uncertainty of each pass rate.

Bailey, Daniel W.; Nelms, Benjamin E.; Attwood, Kristopher; Kumaraswamy, Lalith; Podgorsak, Matthew B. [Department of Physics, State University of New York at Buffalo, Buffalo, New York 14260 (United States) and Department of Radiation Medicine, Roswell Park Cancer Institute, Buffalo, New York 14263 (United States); Canis Lupus LLC, Merrimac, Wisconsin 53561 (United States); Department of Biostatistics, Roswell Park Cancer Institute, Buffalo, New York 14263 (United States); Department of Radiation Medicine, Roswell Park Cancer Institute, Buffalo, New York 14263 (United States); Department of Radiation Medicine, Roswell Park Cancer Institute, Buffalo, New York 14263 (United States); Department of Molecular and Cellular Biophysics and Biochemistry, Roswell Park Cancer Institute, Buffalo, New York 14263 (United States) and Department of Physiology and Biophysics, State University of New York at Buffalo, Buffalo, New York 14214 (United States)

2011-11-15T23:59:59.000Z

39

Dosimetry in steep dose-rate gradient radiation fields: A challenge in clinical applications  

Science Conference Proceedings (OSTI)

The fundamental goal of radiotherapy is to reduce the damage to normal tissue and optimize the dose to the tumor with an associated high probability of cure. Because of this, an accurate and precise knowledge of the radiation dose distribution delivered around the tumor volume during radiotherapy treatments such as stereotactic radiosurgery, intensity modulated radiotherapy or brachytherapy with low-energy X-ray and beta particle sources is of great importance. However, in each of these radiation fields, there exists a steep dose-rate gradient which makes it very difficult to perform accurate dose measurements. In this work, the physics phenomena involved in the energy absorption for each of these situations are discussed, and a brief revision of what the Medical Physics community is doing is presented.

Massillon-JL, G. [Instituto de Fisica, Universidad Nacional Autonoma de Mexico, A.P. 20-364, 01000 DF (Mexico)

2010-12-07T23:59:59.000Z

40

A PORTABLE DOSE RATE INSTRUMENT FOR MEASUREMENT OF NATURAL BACK-GROUND RADIATION LEVELS  

SciTech Connect

An instrument of the ionization chamber type which is capable of measuring radiation dose rates down to and below those encountered in natural background was designed and constructed. It consists of a 40-liter ionization chamber coupled to a portable battery-powered electrometer. The chamber polarizing battery is a part of the chamber center electrode assembly and is located inside the chamber. (auth)

Rising, F.L.

1960-12-19T23:59:59.000Z

Note: This page contains sample records for the topic "beta-gamma dose rates" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

Four-dimensional dose distributions of step-and-shoot IMRT delivered with real-time tumor tracking for patients with irregular breathing: Constant dose rate vs dose rate regulation  

SciTech Connect

Purpose: Dose-rate-regulated tracking (DRRT) is a tumor tracking strategy that programs the MLC to track the tumor under regular breathing and adapts to breathing irregularities during delivery using dose rate regulation. Constant-dose-rate tracking (CDRT) is a strategy that dynamically repositions the beam to account for intrafractional 3D target motion according to real-time information of target location obtained from an independent position monitoring system. The purpose of this study is to illustrate the differences in the effectiveness and delivery accuracy between these two tracking methods in the presence of breathing irregularities. Methods: Step-and-shoot IMRT plans optimized at a reference phase were extended to remaining phases to generate 10-phased 4D-IMRT plans using segment aperture morphing (SAM) algorithm, where both tumor displacement and deformation were considered. A SAM-based 4D plan has been demonstrated to provide better plan quality than plans not considering target deformation. However, delivering such a plan requires preprogramming of the MLC aperture sequence. Deliveries of the 4D plans using DRRT and CDRT tracking approaches were simulated assuming the breathing period is either shorter or longer than the planning day, for 4 IMRT cases: two lung and two pancreatic cases with maximum GTV centroid motion greater than 1 cm were selected. In DRRT, dose rate was regulated to speed up or slow down delivery as needed such that each planned segment is delivered at the planned breathing phase. In CDRT, MLC is separately controlled to follow the tumor motion, but dose rate was kept constant. In addition to breathing period change, effect of breathing amplitude variation on target and critical tissue dose distribution is also evaluated. Results: Delivery of preprogrammed 4D plans by the CDRT method resulted in an average of 5% increase in target dose and noticeable increase in organs at risk (OAR) dose when patient breathing is either 10% faster or slower than the planning day. In contrast, DRRT method showed less than 1% reduction in target dose and no noticeable change in OAR dose under the same breathing period irregularities. When {+-}20% variation of target motion amplitude was present as breathing irregularity, the two delivery methods show compatible plan quality if the dose distribution of CDRT delivery is renormalized. Conclusions: Delivery of 4D-IMRT treatment plans, stemmed from 3D step-and-shoot IMRT and preprogrammed using SAM algorithm, is simulated for two dynamic MLC-based real-time tumor tracking strategies: with and without dose-rate regulation. Comparison of cumulative dose distribution indicates that the preprogrammed 4D plan is more accurately and efficiently conformed using the DRRT strategy, as it compensates the interplay between patient breathing irregularity and tracking delivery without compromising the segment-weight modulation.

Yang Xiaocheng; Han-Oh, Sarah; Gui Minzhi; Niu Ying; Yu, Cedric X.; Yi Byongyong [Department of Radiation Oncology, University of Maryland School of Medicine, Baltimore, Maryland 21201 (United States); Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland 21231 (United States); Medical Physics Division, Saint Agnes Cancer Center, Baltimore, Maryland 21229 (United States); Department of Physics, George Washington University, Washington, DC 20052 (United States); Department of Radiation Oncology, University of Maryland School of Medicine, Baltimore, Maryland 21201 (United States)

2012-09-15T23:59:59.000Z

42

Correlation of External Exposure and Dose Equivalent Rates with Uranium Surface Contamination  

SciTech Connect

This report provides both calculated estimates and measured values of exposure in air and tissue dose from external penetrating radiation at a distance of 1 m from uranium contamination on surfaces at the Oak Ridge Y-12 Plant, in support of the Y-12 Site Radiological Characterization Study. Calculated values are based on the total energy from gamma rays and X rays emitted by uranium and its shordaughters at secular equilibrium. Results of a small number of measurements are provided for comparison. Dose rate values derived here are limited to those of external penetrating radiation from distributed sources with limited surface area and from point sources.

Ashley, J.C.; Bogard, J.S.; Brown, K.S.; England, C.A.; Hamm, R.N.; Turner, J.E.

1999-06-01T23:59:59.000Z

43

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

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.

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

2013-05-14T23:59:59.000Z

44

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

SciTech Connect

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.

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

2012-05-24T23:59:59.000Z

45

Dose Rate Calucaltion for the DHL W/DOE SNF Codisposal Waste Package  

SciTech Connect

The purpose of this calculation is to determine the surface dose rates of the short codisposal waste package (WP) of defense high-level waste (DHLW) and TRIGA (Training, Research, Isotopes, General Atomics) spent nuclear fuel (SNF). The WP contains the TRIGA SNF, in a standardized 18-in. DOE (U.S. Department of Energy) SNF canister, and five 3-m-long Savannah River Site (SRS) DHLW pour glass canisters, which surround the DOE SNF canister.

G. Radulescu

2000-02-12T23:59:59.000Z

46

Dose Rates from Plutonium Metal and Beryllium Metal in a 9975 Shipping Container  

SciTech Connect

A parametric study was performed of the radiation dose rates that might be produced if plutonium metal and beryllium metal were shipped in the 9975 shipping package. These materials consist of heterogeneous combinations plutonium metal and beryllium. The plutonium metal content varies up to 4.4 kilograms while the beryllium metal varies up to 4 kilograms. This paper presents the results of that study.

Nathan, S.J.

2002-02-04T23:59:59.000Z

47

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

Science Conference Proceedings (OSTI)

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.

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

2012-05-09T23:59:59.000Z

48

Radiation Leukemogenesis: Applying Basic Science of Epidemiological Estimates of Low Dose Risks and Dose-Rate Effects  

SciTech Connect

The next stage of work has been to examine more closely the A-bomb leukemia data which provides the underpinnings of the risk estimation of CML in the above mentioned manuscript. The paper by Hoel and Li (Health Physics 75:241-50) shows how the linear-quadratic model has basic non-linearities at the low dose region for the leukemias including CML. Pierce et. al., (Radiation Research 123:275-84) have developed distributions for the uncertainty in the estimated exposures of the A-bomb cohort. Kellerer, et. al., (Radiation and Environmental Biophysics 36:73-83) has further considered possible errors in the estimated neutron values and with changing RBE values with dose and has hypothesized that the tumor response due to gamma may not be linear. We have incorporated his neutron model and have constricted new A-bomb doses based on his model adjustments. The Hoel and Li dose response analysis has also been applied using the Kellerer neutron dose adjustments for the leukemias. Finally, both Pierce's dose uncertainties and Kellerer neutron adjustments are combined as well as the varying RBE with dose as suggested by Rossi and Zaider and used for leukemia dose-response analysis. First the results of Hoel and Li showing a significantly improved fit of the linear-quadratic dose response by the inclusion of a threshold (i.e. low-dose nonlinearity) persisted. This work has been complete for both solid tumor as well as leukemia for both mortality as well as incidence data. The results are given in the manuscript described below which has been submitted to Health Physics.

Hoel, D. G.

1998-11-01T23:59:59.000Z

49

Objective method to report planner-independent skin/rib maximal dose in balloon-based high dose rate (HDR) brachytherapy for breast cancer  

Science Conference Proceedings (OSTI)

Purpose: An objective method was proposed and compared with a manual selection method to determine planner-independent skin and rib maximal dose in balloon-based high dose rate (HDR) brachytherapy planning. Methods: The maximal dose to skin and rib was objectively extracted from a dose volume histogram (DVH) of skin and rib volumes. A virtual skin volume was produced by expanding the skin surface in three dimensions (3D) external to the breast with a certain thickness in the planning computed tomography (CT) images. Therefore, the maximal dose to this volume occurs on the skin surface the same with a conventional manual selection method. The rib was also delineated in the planning CT images and its maximal dose was extracted from its DVH. The absolute (Abdiff=|D{sub max}{sup Man}-D{sub max}{sup DVH}|) and relative (Rediff[%]=100x(|D{sub max}{sup Man}-D{sub max}{sup DVH}|)/D{sub max}{sup DVH}) maximal skin and rib dose differences between the manual selection method (D{sub max}{sup Man}) and the objective method (D{sub max}{sup DVH}) were measured for 50 balloon-based HDR (25 MammoSite and 25 Contura) patients. Results: The average{+-}standard deviation of maximal dose difference was 1.67%{+-}1.69% of the prescribed dose (PD). No statistical difference was observed between MammoSite and Contura patients for both Abdiff and Rediff[%] values. However, a statistically significant difference (p value dose difference compared with maximal skin dose difference for both Abdiff (2.30%{+-}1.71% vs 1.05%{+-}1.43%) and Rediff[%] (2.32%{+-}1.79% vs 1.21%{+-}1.41%). In general, rib has a more irregular contour and it is more proximally located to the balloon for 50 HDR patients. Due to the inverse square law factor, more dose difference was observed in higher dose range (D{sub max}>90%) compared with lower dose range (D{sub max}low dose ranges. Conclusions: The objective method using volumetric information of skin and rib can determine the planner-independent maximal dose compared with the manual selection method. However, the difference was dose point in 3D planning CT images.

Kim, Yongbok; Trombetta, Mark G. [Department of Radiation Oncology, Allegheny General Hospital, Pittsburgh, Pennsylvania 15212 (United States) and Drexel University College of Medicine, Allegheny Campus, Pittsburgh, Pennsylvania 15212 (United States)

2011-04-15T23:59:59.000Z

50

Radiosensitization of Human Cervical Cancer Cells by Inhibiting Ribonucleotide Reductase: Enhanced Radiation Response at Low-Dose Rates  

Science Conference Proceedings (OSTI)

Purpose: To test whether pharmacologic inhibition of ribonucleotide reductase (RNR) by 3-aminopyridine-2-carboxaldehyde thiosemicarbazone (3-AP, NSC no. 663249) enhances radiation sensitivity during low-dose-rate ionizing radiation provided by a novel purpose-built iridium-192 cell irradiator. Methods and Materials: The cells were exposed to low-dose-rate radiation (11, 23, 37, 67 cGy/h) using a custom-fabricated cell irradiator or to high-dose-rate radiation (330 cGy/min) using a conventional cell irradiator. The radiation sensitivity of human cervical (CaSki, C33-a) cancer cells with or without RNR inhibition by 3-AP was evaluated using a clonogenic survival and an RNR activity assay. Alteration in the cell cycle distribution was monitored using flow cytometry. Results: Increasing radiation sensitivity of both CaSki and C33-a cells was observed with the incremental increase in radiation dose rates. 3-AP treatment led to enhanced radiation sensitivity in both cell lines, eliminating differences in cell cytotoxicity from the radiation dose rate. RNR blockade by 3-AP during low-dose-rate irradiation was associated with low RNR activity and extended G{sub 1}-phase cell cycle arrest. Conclusions: We conclude that RNR inhibition by 3-AP impedes DNA damage repair mechanisms that rely on deoxyribonucleotide production and thereby increases radiation sensitivity of human cervical cancers to low-dose-rate radiation.

Kunos, Charles A., E-mail: charles.kunos@UHhospitals.org [Department of Radiation Oncology, University Hospitals Case Medical Center and Case Western Reserve School of Medicine, Cleveland, OH (United States); Colussi, Valdir C. [Department of Radiation Oncology, University Hospitals Case Medical Center and Case Western Reserve School of Medicine, Cleveland, OH (United States); Pink, John [Department of General Medical Sciences, University Hospitals Case Medical Center and Case Western Reserve School of Medicine, Cleveland, OH (United States); Radivoyevitch, Tomas [Department of Epidemiology and Biostatistics, Case Comprehensive Cancer Center, University Hospitals Case Medical Center and Case Western Reserve School of Medicine, Cleveland, OH (United States); Oleinick, Nancy L. [Department of Radiation Oncology, University Hospitals Case Medical Center and Case Western Reserve School of Medicine, Cleveland, OH (United States)

2011-07-15T23:59:59.000Z

51

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

Science Conference Proceedings (OSTI)

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.

Nathan, S.

2011-08-23T23:59:59.000Z

52

Nuclear mass inventory, photon dose rate and thermal decay heat of spent research reactor fuel assemblies  

SciTech Connect

This document has been prepared to assist research reactor operators possessing spent fuel containing enriched uranium of United States origin to prepare part of the documentation necessary to ship this fuel to the United States. Data are included on the nuclear mass inventory, photon dose rate, and thermal decay heat of spent research reactor fuel assemblies. Isotopic masses of U, Np, Pu and Am that are present in spent research reactor fuel are estimated for MTR, TRIGA and DIDO-type fuel assembly types. The isotopic masses of each fuel assembly type are given as functions of U-235 burnup in the spent fuel, and of initial U-235 enrichment and U-235 mass in the fuel assembly. Photon dose rates of spent MTR, TRIGA and DIDO-type fuel assemblies are estimated for fuel assemblies with up to 80% U-235 burnup and specific power densities between 0.089 and 2.857 MW/kg[sup 235]U, and for fission product decay times of up to 20 years. Thermal decay heat loads are estimated for spent fuel based upon the fuel assembly irradiation history (average assembly power vs. elapsed time) and the spent fuel cooling time.

Pond, R.B.; Matos, J.E.

1996-12-31T23:59:59.000Z

53

A Comprehensive Analysis of Cardiac Dose in Balloon-Based High-Dose-Rate Brachytherapy for Left-Sided Breast Cancer  

SciTech Connect

Purpose: To investigate radiation dose to the heart in 60 patients with left-sided breast cancer who were treated with balloon-based high-dose-rate brachytherapy using MammoSite or Contura applicators. Methods and Materials: We studied 60 consecutive women with breast cancer who were treated with 34 Gy in 10 twice-daily fractions using MammoSite (n = 37) or Contura (n = 23) applicators. The whole heart and the left and right ventricles were retrospectively delineated, and dose-volume histograms were analyzed. Multiple dosimetrics were reported, such as mean dose (D{sub mean}); relative volume receiving 1.7, 5, 10, and 20 Gy (V1.7, V5, V10, and V20, respectively); dose to 1 cc (D{sub 1cc}); and maximum point dose (D{sub max}). Biologic metrics, biologically effective dose and generalized equivalent uniform dose were computed. The impact of lumpectomy cavity location on cardiac dose was investigated. Results: The average {+-} standard deviation of D{sub mean} was 2.45 {+-} 0.94 Gy (range, 0.56-4.68) and 3.29 {+-} 1.28 Gy (range, 0.77-6.35) for the heart and the ventricles, respectively. The average whole heart V5 and V10 values were 10.2% and 1.3%, respectively, and the heart D{sub max} was >20 Gy in 7 of 60 (11.7%) patients and >25 Gy in 3 of 60 (5%) patients. No cardiac tissue received {>=}30 Gy. The V1.7, V5, V10, V20, and D{sub mean} values were all higher for the ventricles than for the whole heart. For balloons located in the upper inner quadrant of the breast, the average whole heart D{sub mean} was highest. The D{sub mean}, biologically effective dose, and generalized equivalent uniform dose values for heart and ventricles decreased with increasing minimal distance from the surface of the balloon. Conclusions: On the basis of these comprehensive cardiac dosimetric data, we recommend that cardiac dose be routinely reported and kept as low as possible in balloon-based high-dose-rate brachytherapy treatment planning for patients with left-sided breast cancer so the correlation with future cardiac toxicity data can be investigated.

Valakh, Vladimir, E-mail: vladimir@valakh.com [Department of Radiation Oncology, Allegheny General Hospital, Pittsburgh, PA (United States); Kim, Yongbok; Werts, E. Day; Trombetta, Mark G. [Department of Radiation Oncology, Allegheny General Hospital, Pittsburgh, PA (United States); Drexel University College of Medicine, Allegheny Campus, Pittsburgh, PA (United States)

2012-04-01T23:59:59.000Z

54

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

DOE Patents (OSTI)

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.

Horn, Kevin M. (Albuquerque, NM)

2008-05-20T23:59:59.000Z

55

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

Science Conference Proceedings (OSTI)

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.

Nathan, S.

2012-06-14T23:59:59.000Z

56

Estimated effective dose rates from radon exposure in workplaces and residences within Los Alamos county in New Mexico  

SciTech Connect

Many millions of office workers are exposed to radon while at work and at home. Though there has been a multitude of studies reporting the measurements of radon concentrations and potential lung and effective doses associated with radon and progeny exposure in homes, similar studies on the concentrations and subsequent effective dose rates in the workplace are lacking. The purposes of this study were to measure radon concentrations in office and residential spaces in the same county and explore the radiation dose implications. Sixty-five track-etch detectors were deployed in office spaces and 47 were deployed in residences, all within Los Alamos County, New Mexico, USA. The sampling periods for these measurements were generally about three months. The measured concentrations were then used to calculate and compare effective dose rates resulting from exposure while at work and at home. Results showed that full-time office workers receive on average about nine times greater exposure at home than while in the office (691 mrem yr{sup -1} versus 78 mrem yr{sup -1}). The estimated effective dose rate for a more homebound person was 896 mrem yr{sup -1}. These effective dose rates are contrasted against the 100 mrem yr{sup -1} threshold for regulation of a 'radiological worker' defined in the Department of Energy regulations occupational exposure and the 10 mrem yr{sup -1} air pathway effective public dose limit regulated by the Environmental Protection Agency.

Whicker, Jeffrey J [Los Alamos National Laboratory; Mcnaughton, Michael [Los Alamos National Laboratory

2009-01-01T23:59:59.000Z

57

Commissioning of the Electron Line of the Linac Coherent Light Source. Dose Rate Measurements and Simulations  

Science Conference Proceedings (OSTI)

The Linac Coherent Light Source at the SLAC National Accelerator Laboratory (operated by Stanford University for the US Department of Energy) is the world's first hard X-ray Free Electron Laser machine. It uses high energy electrons delivered by a linac to create ultrafast and brilliant X-ray pulses that can be used as a 'high-speed' camera to obtain images of atoms and molecules. LCLS is a pioneer machine and, as such, its design has encountered unprecedented challenges, the solutions to which will benefit future facilities of its kind across the globe. This article describes the radiation protection aspects of LCLS electron beamlines. Special emphasis is put on the successful commissioning of the LCLS electron line, where, for all examined loss sources, the measured prompt and residual dose rates are in agreement with or below the values predicted through detailed Monte Carlo simulations, used earlier to design the shielding.

Santana Leitner, M; Bauer, J.M.; Fasso, A.; Liu, J.C.; Mao, X.S.; Prinz, A.; Rokni, H.; /SLAC; Sanami, T.; /SLAC /KEK, Tsukuba; Vollaire, J.; /SLAC

2009-05-20T23:59:59.000Z

58

Online Monitoring And Determination Of Environmental Dose Rate, Using Radiological Network In Albania  

Science Conference Proceedings (OSTI)

From May 2004, in the Institute of Nuclear Physics is installed Albanian Radiological Monitoring Network, in the framework of emergency monitoring in the territory of Albania. In this network, this is unique monitoring on-line system in our country. are included 5(five) monitoring stations, respectively in Tirane, Shkoder, Kukes, Korce and Vlore. The last four stations are near Albanian borders The network performs measures of ambient dose rate in a range from 5 nSv/h up to 10 Sv/h. For measurements are used detector of type VACUTEC 70045 A, which are calibrated in the Centre of Applied Nuclear Physics, University of Tirana, using standard radiation source Cs-137. This monitoring help to warn in real time the relative authorities, in case of radiological accidents of 5th degree (for example accidents in nuclear power plants, near Albanian territory).

Telhaj, Ervis [Centre of Applied Nuclear Physics, Faculty of Natural Sciences, University of Tirana (Albania); Deda, Antoneta [Department of Physics, Faculty of Natural Sciences, University of Tirana (Albania)

2010-01-21T23:59:59.000Z

59

Work to save dose: contrasting effective dose rates from radon exposure in workplaces and residences against the backdrop of public and occupational limits  

Science Conference Proceedings (OSTI)

Office workers are exposed to radon while at work and at home. Though there has been a multitude of studies reporting the measurements of radon concentrations and potential lung and effective doses associated with radon and progeny exposure in homes, similar studies on the concentrations and subsequent effective dose rates in the non-mine workplaces are lacking. Additionally, there are few, if any, comparative analyses of radon exposures at more 'typical' workplace with residential exposures within the same county. The purposes of this study were to measure radon concentrations in office and residential spaces in the same county and explore the radiation dose implications. Sixty-five track-etch detectors were deployed in office spaces and 47 were deployed in residences, all within Los Alamos County, New Mexico, USA. The sampling periods for these measurements were generally about three months. The measured concentrations were used to calculate and compare effective dose rates resulting from exposure while at work and at home. Results showed that full-time office workers receive on average about 8 times greater exposure at home than while in the office (2.3 mSv yr-! versus 0.3 mSv yr-!). The estimated effective dose rate for a more homebound person was about 3 mSv yr-!. Estimating effective doses from background radon exposure in the same county as Los Alamos National Laboratory, with thousands of'radiological workers,' highlights interesting contrasts in radiation protection standards that span public and occupational settings. For example, the effective dose rate from background radon exposure in unregulated office spaces ranged up to 1.1 mSv yr-!, which is similar to the 1 mSv yr-! threshold for regulation ofa 'radiological worker,' as defined in the Department of Energy regulations for occupational exposure. Additionally, the estimated average effective dose total of> 3 mSv yf! from radon background exposure in homes stands in contrast to the 0.1 mSv yr-! air pathway effective public dose limit regulated by the Environmental Protection Agency for radioactive air emissions.

Whicker, Jeffrey J [Los Alamos National Laboratory; Mcnaughton, Michael W [Los Alamos National Laboratory

2009-01-01T23:59:59.000Z

60

A Preliminary Analysis of Dose Rates Associated with ITER CVCS Equipment/Area Location  

DOE Green Energy (OSTI)

A preliminary analysis of the ITER Chemical and Volume Control System (CVCS) Area was performed to assess dose rates outside the walls and ceiling of the facility after 1.5 years of operation at shutdown, 2 days, and 10 days after shutdown. For this purpose a simplified Monte Carlo computer model was developed using the MCNP (MCNP5 Ver. 1.51) code. Two components are included: the smaller filter tank and the larger ion exchanger. These pieces of equipment are associated with the Integrated Blanket ELM Divertor Primary Heat Transfer System, which will have the largest dose rates associated with activated corrosion products during operation in comparison with other systems. The ion exchanger contained two source regions, a 1.2-m-thick resin bed above a 0.55 m-thick skirt, and a 0.8-m-thick water region. The filter constituted an additional source. Thus the model consisted of three sources (filter, resin, water), homogeneously distributed within the appropriate source regions. However, much of the results (that address individual isotopes) are presented with the two sources in the ion exchanger combined. In these cases the sources are referred to as the 'ion exchanger source' and the 'filter source.' Dimensions for the facility and components, as well as source isotopes and strengths, and material densities, were supplied by US ITER. Because of its simplification, the model does not contain pipes. Consequently, radiation streaming through pipe penetrations, radiation emanating from the pipes, and shielding from the pipes were not considered in this analysis. Dose rates on the outside of two walls and the ceiling were calculated. The two walls are labeled as the 'long' wall (aligned with the X-axis) and the 'short' wall (aligned with the Y-axis). These walls and ceiling were nominally set to 30-cm-thick concrete. In the original analysis, standard concrete (2.3 g/cc density) was used. In addition to the shielding walls/ceiling, a floor and an additional wall opposite the long wall were added for photon scattering contributions. These were both 10-cm-thick, standard concrete structures. Other components (tanks, pipes, etc.), that were not included in the model, would potentially add additional scattering and shielding. Possibly these additional effects will be addressed in a later, more detailed analysis. The room was 29.6 m in length (X-axis), but was limited to 15 m in the model. The inside width (Y axis) and height (Z axis) were 4 m and 3.4 m, respectively. The origin for the model was located inside the room at the corner opposite the long wall and adjacent to the short wall at the floor level. The room was filled with air at standard temperature and pressure. The stainless steel (SS304) wall thicknesses for the ion exchanger and filter were 2.2 cm and 0.8 cm, respectively. The axial center of the filter was located 140 cm from the short wall and 100 cm from the long wall (outer surface). The axial center of the ion exchanger was located 440 cm from the short wall and 250 cm from the long wall (inner surface). The resin was assumed to be a homogeneous mixture of equal atom density fractions of hydrogen and carbon* at a specified density of 1.136 g/cc. The filter material was assumed to be homogeneous carbon at a specified density of 1.8 g/cc. If the filter media were stainless steel and the accumulated activity were the same, the dose rate outside the filter would be lower, provided the density of the stainless steel sintered filter material is significantly higher than 1.8g/cc. The densities of the water and air were assumed to be 1.0 g/cc and 1.096E-3 g/cc, respectively. The model included 10 small volumes placed outside the model adjacent to the wall at locations where the dose rates were expected to be highest and which showed to a degree the fall-off of the dose rate with distance along a particular wall or ceiling. These 'tally cells' are shown in Fig. 2 and are described in Table 1. Each cell had dimensions of 50 cm x 50 cm x 1 cm and was oriented so that the 1-cm-thick dimension was perpendicular to the wall again

Blakeman, Edward D [ORNL; Ilas, Dan [ORNL; Petrov, Andrei Y [ORNL

2012-03-01T23:59:59.000Z

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61

Implementation of High-Dose-Rate Brachytherapy and Androgen Deprivation in Patients With Prostate Cancer  

SciTech Connect

Purpose: To evaluate outcome (overall survival [OS], the actuarial 5-year cancer-specific survival [CSS], disease-free survival [DFS], biochemical failure-free survival [BFS]), complications and morbidity in patients treated with high-dose-rate brachytherapy (HDR-BT) boost and hormonal treatment with curative aims. Methods: Between 2004 and 2009, 275 prospectively followed pN0/N0M0 patients were included: 19 patients (7%) with T2, Gleason score 7 and prostate-specific antigen (PSA) <10 and 256 patients (93%) with T3 or Gleason score 8-10 or PSA >20 received multimodal treatment with conformal four-field radiotherapy (prostate/vesiculae 2 Gy Multiplication-Sign 25) combined with HDR-BT (iridium 192; prostate 10 Gy Multiplication-Sign 2) with long-term androgen deprivation therapy (ADT). Results: After a median observation time of 44.2 months (range, 10.4-90.5 months) 12 patients had relapsed clinically and/or biochemically and 10 patients were dead, of which 2 patients died from prostate cancer. Five-year estimates of BFS, CSS, DFS, and OS rates were 98.5%, 99.3%, 95.6%, and 96.3%, respectively. None of the patients with either Gleason score <8 or with intermediate risk profile had relapsed. The number of HDR-BT treatments was not related to outcome. Despite of age (median, 65.7 years; range, 45.7-77 years) and considerable pretreatment comorbidity in 39 of 275 patients, Genitourinary treatment-related morbidity was moderate with long-lasting Radiation Therapy Oncology Group Grade 2 voiding problems in 26 patients (9.5%) and occasionally mucous discharge in 20 patients (7%), none with Grade >2 for gastrointestinal at follow-up. Complications during implantations were related to pubic arch interference (4 patients) and lithotomy time, causing 2 patients to develop compartment syndrome. Conclusion: Despite still preliminary observations, our 5-year outcome estimates favor the implementation of high-dose-rate brachytherapy in high-risk patients combined with conformal external radiotherapy and long-term ADT. High-quality implants can be achieved by a trained specialized team at a high-turnover center using transrectal ultrasound-based treatment plans with acceptable morbidity and complication rates.

Lilleby, Wolfgang, E-mail: wolfgang.lilleby@ous-hf.no [Cancer Clinic, Oslo University Hospital, Norwegian Radiumhospital, Department of Radiotherapy and Oncology, Oslo (Norway); Tafjord, Gunnar; Raabe, Nils K. [Cancer Clinic, Oslo University Hospital, Norwegian Radiumhospital, Department of Radiotherapy and Oncology, Oslo (Norway)

2012-07-01T23:59:59.000Z

62

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

Science Conference Proceedings (OSTI)

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.

Cheryl G. Burrell, Ph.D.

2012-05-14T23:59:59.000Z

63

Exclusive low-dose-rate brachytherapy in 279 patients with T2N0 mobile tongue carcinoma  

SciTech Connect

Purpose: To evaluate the therapeutic results obtained with {sup 192}Ir low-dose-rate interstitial brachytherapy in T2N0 mobile tongue carcinoma. Patients and Methods: Between December 1979 and January 1998, 279 patients with T2N0 mobile tongue carcinoma were treated by exclusive low-dose-rate brachytherapy, with or without neck dissection. {sup 192}Ir brachytherapy was performed according to the 'Paris system' with a median total dose of 60 Gy (median dose rate, 0.5 Gy/h). Results: Overall survival was 74.3% and 46.6% at 2 and 5 years. Local control was 79.1% at 2 years and regional control, respectively, 75.9% and 69.5% at 2 and 5 years (Kaplan-Meier method). Systematic dissection revealed 44.6% occult node metastases, and histologic lymph node involvement was identified as the main significant factor for survival. Complication rate was 16.5% (Grade 3, 2.9%). Half of the patients presented previous and/or successive malignant tumor (ear-nose-throat, esophagus, or bronchus). Conclusion: Exclusive low-dose-rate brachytherapy is an effective treatment for T2 tongue carcinoma. Regional control and survival are excellent in patients undergoing systematic neck dissection, which is mandatory in our experience because of a high rate of occult lymph node metastases.

Bourgier, Celine [Department of Radiotherapy, Centre Oscar Lambret, Lille (France); Coche-Dequeant, Bernard [Department of Radiotherapy, Centre Oscar Lambret, Lille (France); Fournier, Charles [Department of Biostatistics, Centre Oscar Lambret, Lille (France); Castelain, Bernard [Department of Radiotherapy, Centre Oscar Lambret, Lille (France); Prevost, Bernard [Department of Radiotherapy, Centre Oscar Lambret, Lille (France); Lefebvre, Jean-Louis [Department of Head and Neck Surgery, Centre Oscar Lambret, Lille (France); Lartigau, Eric [Department of Radiotherapy, Centre Oscar Lambret, Lille (France)]. E-mail: e-lartigau@o-lambret.fr

2005-10-01T23:59:59.000Z

64

Chloroquine Improves Survival and Hematopoietic Recovery After Lethal Low-Dose-Rate Radiation  

SciTech Connect

Purpose: We have previously shown that the antimalarial agent chloroquine can abrogate the lethal cellular effects of low-dose-rate (LDR) radiation in vitro, most likely by activating the ataxia-telangiectasia mutated (ATM) protein. Here, we demonstrate that chloroquine treatment also protects against lethal doses of LDR radiation in vivo. Methods and Materials: C57BL/6 mice were irradiated with a total of 12.8 Gy delivered at 9.4 cGy/hour. ATM null mice from the same background were used to determine the influence of ATM. Chloroquine was administered by two intraperitoneal injections of 59.4 {mu}g per 17 g of body weight, 24 hours and 4 hours before irradiation. Bone marrow cells isolated from tibia, fibula, and vertebral bones were transplanted into lethally irradiated CD45 congenic recipient mice by retroorbital injection. Chimerism was assessed by flow cytometry. In vitro methylcellulose colony-forming assay of whole bone marrow cells and fluorescence activated cell sorting analysis of lineage depleted cells were used to assess the effect of chloroquine on progenitor cells. Results: Mice pretreated with chloroquine before radiation exhibited a significantly higher survival rate than did mice treated with radiation alone (80% vs. 31%, p = 0.0026). Chloroquine administration before radiation did not affect the survival of ATM null mice (p = 0.86). Chloroquine also had a significant effect on the early engraftment of bone marrow cells from the irradiated donor mice 6 weeks after transplantation (4.2% vs. 0.4%, p = 0.015). Conclusion: Chloroquine administration before radiation had a significant effect on the survival of normal but not ATM null mice, strongly suggesting that the in vivo effect, like the in vitro effect, is also ATM dependent. Chloroquine improved the early engraftment of bone marrow cells from LDR-irradiated mice, presumably by protecting the progenitor cells from radiation injury. Chloroquine thus could serve as a very useful drug for protection against the harmful effects of LDR radiation.

Lim Yiting [Department of Oncology, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, Maryland (United States)] [Department of Oncology, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, Maryland (United States); Hedayati, Mohammad; Merchant, Akil A.; Zhang Yonggang; Yu, Hsiang-Hsuan M. [Department of Radiation Oncology and Molecular Radiation Sciences, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, Maryland (United States)] [Department of Radiation Oncology and Molecular Radiation Sciences, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, Maryland (United States); Kastan, Michael B. [Department of Oncology, St. Jude Children's Research Hospital, Memphis, Tennessee (United States) [Department of Oncology, St. Jude Children's Research Hospital, Memphis, Tennessee (United States); Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, North Carolina (United States); Matsui, William, E-mail: matsuwi@jhmi.edu [Department of Oncology, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, Maryland (United States)] [Department of Oncology, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, Maryland (United States); DeWeese, Theodore L., E-mail: deweete@jhmi.edu [Department of Radiation Oncology and Molecular Radiation Sciences, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, Maryland (United States)

2012-11-01T23:59:59.000Z

65

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

DOE Patents (OSTI)

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.

Horn, Kevin M. (Albuquerque, NM)

2006-03-28T23:59:59.000Z

66

Novel Hybrid Monte Carlo/Deterministic Technique for Shutdown Dose Rate Analyses of Fusion Energy Systems  

SciTech Connect

The rigorous 2-step (R2S) method uses three-dimensional Monte Carlo transport simulations to calculate the shutdown dose rate (SDDR) in fusion reactors. Accurate full-scale R2S calculations are impractical in fusion reactors because they require calculating space- and energy-dependent neutron fluxes everywhere inside the reactor. The use of global Monte Carlo variance reduction techniques was suggested for accelerating the neutron transport calculation of the R2S method. The prohibitive computational costs of these approaches, which increase with the problem size and amount of shielding materials, inhibit their use in the accurate full-scale neutronics analyses of fusion reactors. This paper describes a novel hybrid Monte Carlo/deterministic technique that uses the Consistent Adjoint Driven Importance Sampling (CADIS) methodology but focuses on multi-step shielding calculations. The Multi-Step CADIS (MS-CADIS) method speeds up the Monte Carlo neutron calculation of the R2S method using an importance function that represents the importance of the neutrons to the final SDDR. Using a simplified example, preliminarily results showed that the use of MS-CADIS enhanced the efficiency of the neutron Monte Carlo simulation of an SDDR calculation by a factor of 550 compared to standard global variance reduction techniques, and that the increase over analog Monte Carlo is higher than 10,000.

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

2013-01-01T23:59:59.000Z

67

Nonlinear model predictive control for dosing daily anticancer agents using a novel saturating-rate cell-cycle model  

Science Conference Proceedings (OSTI)

A nonlinear model predictive control (NMPC) algorithm was developed to dose the chemotherapeutic agent tamoxifen based on a novel saturating-rate, cell-cycle model (SCM). Using daily tumor measurements, the algorithm decreased tumor volume along a specified ... Keywords: Biomedical systems, Cancer, Nonlinear model, Nonlinear model predictive control, Pharmacodynamics, Pharmacokinetics

Jeffry A. Florian, Jr.; Julie L. Eiseman; Robert S. Parker

2008-03-01T23:59:59.000Z

68

Dose-rate-effects in XRCC1 wild-type and mutant CHO cell lines using An ²?¹AM source  

E-Print Network (OSTI)

This work explores the effects of low-dose-rate radiation on both the AA8 (wild-type CHO cells) and EM9 (XRCC1 null CHO mutants) cell lines. In particular, this study performed clonogenic survival and growth assays to ...

Chambers, Dwight McCoy

2008-01-01T23:59:59.000Z

69

MEASURED AND CALCULATED HEATING AND DOSE RATES FOR THE HFIR HB4 BEAM TUBE AND COLD SOURCE  

SciTech Connect

The High Flux Isotope Reactor at the Oak Ridge National Laboratory was upgraded to install a cold source in horizontal beam tube number 4. Calculations were performed and measurements were made to determine heating within the cold source and dose rates within and outside a shield tunnel surrounding the beam tube. This report briefly describes the calculations and presents comparisons of the measured and calculated results. Some calculated dose rates are in fair to good agreement with the measured results while others, particularly those at the shield interfaces, differ greatly from the measured results. Calculated neutron exposure to the Teflon seals in the hydrogen transfer line is about one fourth of the measured value, underpredicting the lifetime by a factor of four. The calculated cold source heating is in good agreement with the measured heating.

Slater, Charles O [ORNL; Primm, Trent [ORNL; Pinkston, Daniel [ORNL; Cook, David Howard [ORNL; Selby, Douglas L [ORNL; Ferguson, Phillip D [ORNL; Bucholz, James A [ORNL; Popov, Emilian L [ORNL

2009-03-01T23:59:59.000Z

70

Low-Dose-Rate Californium-252 Neutron Intracavitary Afterloading Radiotherapy Combined With Conformal Radiotherapy for Treatment of Cervical Cancer  

Science Conference Proceedings (OSTI)

Purpose: To study the efficacy of low-dose-rate californium-252 ({sup 252}Cf) neutron intracavitary afterloading radiotherapy (RT) combined with external pelvic RT for treatment of cervical cancer. Methods and Materials: The records of 96 patients treated for cervical cancer from 2006 to 2010 were retrospectively reviewed. For patients with tumors {radiation was performed (1.8 Gy/day, five times/week) until the dose reached 20 Gy, and then {sup 252}Cf neutron intracavitary afterloading RT (once/week) was begun, and the frequency of external beam radiation was changed to four times/week. For patients with tumors >4 cm, {sup 252}Cf RT was performed one to two times before whole-pelvis external beam radiation. The tumor-eliminating dose was determined by using the depth limit of 5 mm below the mucosa as the reference point. In all patients, the total dose of the external beam radiation ranged from 46.8 to 50 Gy. For {sup 252}Cf RT, the dose delivered to point A was 6 Gy/fraction, once per week, for a total of seven times, and the total dose was 42 Gy. Results: The mean {+-} SD patient age was 54.7 {+-} 13.7 years. Six patients had disease assessed at stage IB, 13 patients had stage IIA, 49 patients had stage IIB, 3 patients had stage IIIA, 24 patients had stage IIIB, and 1 patient had stage IVA. All patients obtained complete tumor regression (CR). The mean {+-} SD time to CR was 23.5 {+-} 3.4 days. Vaginal bleeding was fully controlled in 80 patients within 1 to 8 days. The mean {+-} SD follow-up period was 27.6 {+-} 12.7 months (range, 6-48 months). Five patients died due to recurrence or metastasis. The 3-year survival and disease-free recurrence rates were 89.6% and 87.5 %, respectively. Nine patients experienced mild radiation proctitis, and 4 patients developed radiocystitis. Conclusions: Low-dose-rate {sup 252}Cf neutron RT combined with external pelvic RT is effective for treating cervical cancer, with a low incidence of complications.

Zhang Min [Department of Oncology, Armed Police Hospital of Hangzhou, Hangzhou, Zhejiang Province (China); Xu Hongde [Cancer Center, Armed Police Hospital of Hangzhou, Hangzhou, Zhejiang Province (China); Pan Songdan; Lin Shan; Yue Jianhua [Department of Oncology, Armed Police Hospital of Hangzhou, Hangzhou, Zhejiang Province (China); Liu Jianren, E-mail: liujianren0571@hotmail.com [Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang Province (China)

2012-07-01T23:59:59.000Z

71

High-Dose-Rate Brachytherapy as a Monotherapy for Favorable-Risk Prostate Cancer: A Phase II Trial  

Science Conference Proceedings (OSTI)

Purpose: There are multiple treatment options for favorable-risk prostate cancer. High-dose-rate (HDR) brachytherapy as a monotherapy is appealing, but its use is still investigational. A Phase II trial was undertaken to explore the value of such treatment in low-to-intermediate risk prostate cancer. Methods and Materials: This was a single-institution, prospective study. Eligible patients had low-risk prostate cancer features but also Gleason scores of 7 (51% of patients) and stage T2b to T2c cancer. Treatment with HDR brachytherapy with a single implant was administered over 2 days. One of four fractionation schedules was used in a dose escalation study design: 3 fractions of 10, 10.5, 11, or 11.5 Gy. Patients were assessed with the Common Terminology Criteria for Adverse Events version 2.0 for urinary toxicity, the Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer scoring schema for rectal toxicity, and the Expanded Prostate Cancer Index Composite (EPIC) questionnaire to measure patient-reported health-related quality of life. Biochemical failure was defined as a prostate-specific antigen (PSA) nadir plus 2 ng/ml. Results: Between 2003 and 2008, 79 patients were enrolled. With a median follow-up of 39.5 months, biochemical relapse occurred in 7 patients. Three- and 5-year actuarial biochemical control rates were 88.4% (95% confidence interval [CI], 78.0-96.2%) and 85.1% (95% CI, 72.5-94.5%), respectively. Acute grade 3 urinary toxicity was seen in only 1 patient. There was no instance of acute grade 3 rectal toxicity. Rates of late grade 3 rectal toxicity, dysuria, hematuria, urinary retention, and urinary incontinence were 0%, 10.3%, 1.3%, 9.0%, and 0%, respectively. No grade 4 or greater toxicity was recorded. Among the four (urinary, bowel, sexual, and hormonal) domains assessed with the EPIC questionnaire, only the sexual domain did not recover with time. Conclusions: HDR brachytherapy as a monotherapy for favorable-risk prostate cancer, administered using a single implant over 2 days, is feasible and has acceptable acute and late toxicities. Further follow-up is still required to better evaluate the efficacy of such treatment.

Barkati, Maroie [Division of Radiation Oncology, Peter MacCallum Cancer Centre, East Melbourne (Australia); Williams, Scott G., E-mail: scott.williams@petermac.org [Division of Radiation Oncology, Peter MacCallum Cancer Centre, East Melbourne (Australia); Department of Pathology, University of Melbourne, Melbourne (Australia); Foroudi, Farshad; Tai, Keen Hun; Chander, Sarat [Division of Radiation Oncology, Peter MacCallum Cancer Centre, East Melbourne (Australia); Department of Pathology, University of Melbourne, Melbourne (Australia); Dyk, Sylvia van [Division of Radiation Oncology, Peter MacCallum Cancer Centre, East Melbourne (Australia); See, Andrew [Ballarat Austin Radiation Oncology Centre, Ballarat (Australia); Duchesne, Gillian M. [Division of Radiation Oncology, Peter MacCallum Cancer Centre, East Melbourne (Australia); Department of Pathology, University of Melbourne, Melbourne (Australia)

2012-04-01T23:59:59.000Z

72

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

Science Conference Proceedings (OSTI)

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.

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

2009-11-12T23:59:59.000Z

73

The Effect of Dose Rate on the Frequency of Specific-Locus Mutations Induced in Mouse Spermatogonia is Restricted to Larger Lesions; a Retrospective Analysis of Historical Data  

Science Conference Proceedings (OSTI)

A series of 19 large-scale germ-cell mutagenesis experiments conducted several decades ago led to the conclusion that low-LET radiation delivered to mouse spermatogonia at dose rates of 0.8 R/min and below induced only about one-third as many specific-locus mutations as did single, acute exposures at 24 R/min and above. A two-hit origin of the mutations was deemed unlikely in view of the then prevailing evidence for the small size of genetic lesions in spermatogonia. Instead, the dose-rate effect was hypothesized to be the result of a repair system that exists in spermatogonia, but not in more mature male reproductive cells. More recent genetic and molecular studies on the marker genes have identified the phenotypes associated with specific states of the mutant chromosomes, and it is now possible retrospectively to classify individual past mutations as "large lesions" or "other lesions". The mutation-frequency difference between high and low dose rates is restricted to the large lesion mutations, for which the dose-curve slopes differ by a factor exceeding 3.4. For other lesion mutations, there is essentially no difference between the slopes for protracted and acute irradiations; induced other lesions frequencies per unit dose remain similar for dose rates ranging over more than 7 orders of magnitude. For large lesions, these values rise sharply at dose rates >0.8 R/min, though they remain similar within the whole range of protracted doses, failing to provide evidence for a threshold dose rate. The downward bend at high doses that had been noted for X-ray-induced specific-locus mutations as a whole and ascribed to a positive correlation between spermatogonial death and mutation load is now found to be restricted to large lesion mutations. There is a marked difference between the mutation spectra (distributions among the seven loci) for large lesions and other lesions. Within each class, however, the spectra are similar for acute and protracted irradiation.

Russell, Liane B [ORNL; Hunsicker, Patricia R [ORNL

2012-01-01T23:59:59.000Z

74

ACDOS1: a computer code to calculate dose rates from neutron activation of neutral beamlines and other fusion-reactor components  

Science Conference Proceedings (OSTI)

A computer code has been written to calculate neutron induced activation of neutral-beam injector components and the corresponding dose rates as a function of geometry, component composition, and time after shutdown. The code, ACDOS1, was written in FORTRAN IV to calculate both activity and dose rates for up to 30 target nuclides and 50 neutron groups. Sufficient versatility has also been incorporated into the code to make it applicable to a variety of general activation problems due to neutrons of energy less than 20 MeV.

Keney, G.S.

1981-08-01T23:59:59.000Z

75

Accelerated Partial Breast Irradiation With Low-Dose-Rate Interstitial Implant Brachytherapy After Wide Local Excision: 12-Year Outcomes From a Prospective Trial  

Science Conference Proceedings (OSTI)

Purpose: To evaluate the long-term toxicity, cosmesis, and local control of accelerated partial breast irradiation with implant brachytherapy after wide local excision for Stage T1N0 breast cancer (BCa). Materials and Methods: Between 1997 and 2001, 50 patients with Stage T1N0M0 BCa were treated in a Phase I-II protocol using low-dose-rate accelerated partial breast irradiation with implant brachytherapy after wide local excision and lymph node surgery. The total dose was escalated in three groups: 50 Gy (n = 20), 55 Gy (n = 17), and 60 Gy (n = 13). Patient- and physician-assessed breast cosmesis, patient satisfaction, toxicity, mammographic abnormalities, repeat biopsies, and disease status were prospectively evaluated at each visit. Kendall's tau ({tau}{sub {beta}}) and logistic regression analyses were used to correlate outcomes with dose, implant volume, patient age, and systemic therapy. Results: The median follow-up period was 11.2 years (range, 4-14). The patient satisfaction rate was 67%, 67% reported good-excellent cosmesis, and 54% had moderate-severe fibrosis. Higher dose was correlated with worse cosmetic outcome ({tau}{sub {beta}} 0.6, p =}1 cm{sup 2}. Grade 3-4 late skin and subcutaneous toxicities were seen in 4 patients (9%) and 6 patients (13%), respectively, and both correlated with higher dose ({tau}{sub {beta}} 0.3-0.5, p {Low-dose-rate accelerated partial breast irradiation with implant brachytherapy provides acceptable local control in select early-stage BCa patients. However, treatment-related toxicity and cosmetic complications were significant with longer follow-up and at higher doses.

Hattangadi, Jona A. [Harvard Radiation Oncology Program, Boston, MA (United States); Powell, Simon N. [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, NY (United States); MacDonald, Shannon M.; Mauceri, Thomas; Ancukiewicz, Marek [Department of Radiation Oncology, Massachusetts General Hospital, Boston, MA (United States); Freer, Phoebe [Department of Radiology, Massachusetts General Hospital, Boston, MA (United States); Lawenda, Brian [21st Century Oncology, Las Vegas, NV (United States); Alm El-Din, Mohamed A. [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, NY (United States); Department of Clinical Oncology, Tanta University Hospital, Tanta (Egypt); Gadd, Michele A.; Smith, Barbara L. [Department of Surgical Oncology, Massachusetts General Hospital, Boston, MA (United States); Taghian, Alphonse G., E-mail: ataghian@partners.org [Department of Radiation Oncology, Massachusetts General Hospital, Boston, MA (United States)

2012-07-01T23:59:59.000Z

76

Factors Associated With Chest Wall Toxicity After Accelerated Partial Breast Irradiation Using High-Dose-Rate Brachytherapy  

Science Conference Proceedings (OSTI)

Purpose: The purpose of this analysis was to evaluate dose-volume relationships associated with a higher probability for developing chest wall toxicity (pain) after accelerated partial breast irradiation (APBI) by using both single-lumen and multilumen brachytherapy. Methods and Materials: Rib dose data were available for 89 patients treated with APBI and were correlated with the development of chest wall/rib pain at any point after treatment. Ribs were contoured on computed tomography planning scans, and rib dose-volume histograms (DVH) along with histograms for other structures were constructed. Rib DVH data for all patients were sampled at all volumes {>=}0.008 cubic centimeter (cc) (for maximum dose related to pain) and at volumes of 0.5, 1, 2, and 3 cc for analysis. Rib pain was evaluated at each follow-up visit. Patient responses were marked as yes or no. No attempt was made to grade responses. Eighty-nine responses were available for this analysis. Results: Nineteen patients (21.3%) complained of transient chest wall/rib pain at any point in follow-up. Analysis showed a direct correlation between total dose received and volume of rib irradiated with the probability of developing rib/chest wall pain at any point after follow-up. The median maximum dose at volumes {>=}0.008 cc of rib in patients who experienced chest wall pain was 132% of the prescribed dose versus 95% of the prescribed dose in those patients who did not experience pain (p = 0.0035). Conclusions: Although the incidence of chest wall/rib pain is quite low with APBI brachytherapy, attempts should be made to keep the volume of rib irradiated at a minimum and the maximum dose received by the chest wall as low as reasonably achievable.

Brown, Sheree, E-mail: shereedst32@hotmail.com [Department of Radiation Oncology, WellStar Kennestone Hospital, Marietta, Georgia (United States); Vicini, Frank [Department of Radiation Oncology, William Beaumont Hospital, Royal Oak, Michigan (United States); Vanapalli, Jyotsna R.; Whitaker, Thomas J.; Pope, D. Keith [Department of Radiation Oncology, WellStar Kennestone Hospital, Marietta, Georgia (United States); Lyden, Maureen [BioStat International, Inc., Tampa, Florida (United States); Bruggeman, Lisa; Haile, Kenneth L.; McLaughlin, Mark P. [Department of Radiation Oncology, WellStar Kennestone Hospital, Marietta, Georgia (United States)

2012-07-01T23:59:59.000Z

77

RATES  

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Planning & Projects Planning & Projects Power Marketing Rates You are here: SN Home page > Power Marketing > RATES Rates and Repayment Services Rates Current Rates Power Revenue Requirement Worksheet (FY 2014) (Oct 2013 - Sep 2014) (PDF - 30K) PRR Notification Letter (Sep 27, 2013) (PDF - 959K) FY 2012 FP% True-Up Calculations(PDF - 387K) Variable Resource Scheduling Charge FY12-FY16 (October 1, 2012) PRR Forecast FY14-FY17 (May 23, 2013) (PDF - 100K) Forecasted Transmission Rates (May 2013) (PDF - 164K) Past Rates 2013 2012 2011 2010 2009 Historical CVP Transmission Rates (April 2013) (PDF - 287K) Rate Schedules Power - CV-F13 - CPP-2 Transmission - CV-T3 - CV-NWT5 - PACI-T3 - COTP-T3 - CV-TPT7 - CV-UUP1 Ancillary - CV-RFS4 - CV-SPR4 - CV-SUR4 - CV-EID4 - CV-GID1 Federal Register Notices - CVP, COTP and PACI

78

RATES  

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Marketing > RATES Marketing > RATES RATES Current Rates Past Rates 2006 2007 2008 2009 2010 2011 2012 Rates Schedules Power CV-F13 CPP-2 Transmissions CV-T3 CV-NWT5 PACI-T3 COTP-T3 CV-TPT7 CV-UUP1 Ancillary CV-RFS4 CV-SPR4 CV-SUR4 CV-EID4 CV-GID1 Future and Other Rates SNR Variable Resource Scheduling Charge FY12-FY16 (October 1, 2012) SNR Rates Process Calendar (PDF - 171K) Procedures Informal Process Transmission Action Items List (PDF - 144K) Power Action Item List updated on 4-27-10 (PDF - 155K) Power Action Item List (Quick links to relevant documents) Formal Process Rates Brochure (01/11/2011) (PDF - 900K) Appendix A - Federal Register Notice (01/03/2011) (PDF - 8000K) Appendix B - Central Valley Project Power Repayment Study (PDF - 22,322K) Appendix C - Development of the CVP Cost of Service Study (PDF - 2038K)

79

RATES  

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RATES RATES Rates Document Library SNR Rates Process Calendar (PDF - 171K) Procedures Informal Process Transmission Action Items List (PDF - 144K) Power Action Item List updated on 4-27-10 (PDF - 155K) Power Action Item List (Quick links to relevant documents) Formal Process Rates Brochure (01/11/2011) (PDF - 900K) Appendix A - Federal Register Notice (01/03/2011) (PDF - 8000K) Appendix B - Central Valley Project Power Repayment Study (PDF - 22,322K) Appendix C - Development of the CVP Cost of Service Study (PDF - 2038K) Appendix D - Western Transmission System Facilities Map (PDF - 274K) Appendix E - Estimated FY12 FP and BR Customer (PDF - 1144K) Appendix F - Forecasted Replacements and Additions FY11 - FY16 (PDF - 491K) Appendix G - Definitions (PDF - 1758K) Appendix H - Acronyms (PDF - 720K)

80

Semicontinuous Low-Dose-Rate Teletherapy for the Treatment of Recurrent Glial Brain Tumors: Final Report of a Phase I/II Study  

Science Conference Proceedings (OSTI)

Purpose: Semicontinuous low-dose-rate teletherapy (SLDR) is a novel irradiation strategy that exploits the increased radiosensitivity of glial cells in a narrow range of reduced dose rate. We present the final report of a prospective Phase I/II study testing the feasibility of SLDR for the treatment of recurrent gliomas. Methods and Materials: Patients with previously irradiated recurrent gliomas were enrolled from November 1993 to March 1998. Patients received SLDR, delivered 6 to 8 hours/day at a dose rate of 40 to 50 cGy/hour for a total dose of 30 to 35 Gy given over 12 days using a modified cobalt-60 treatment unit. Acute central nervous system toxicity after SLDR treatment was the primary endpoint. Overall survival was a secondary endpoint. Results: Twenty patients were enrolled (14 World Health Organization Grade 4 glioma, 5 Grade 2 glioma, 1 ependymoma). No patients developed {>=}Grade 3 central nervous system toxicity at 3 months without radiographic evidence of tumor progression. Overall survival after SLDR was 56% at 6 months, 28% at 12 months, and 17% at 24 months. One patient survived >48 months, and 1 patient survived >60 months after SLDR treatment. Re-resection before SLDR treatment significantly improved 1-year overall survival for all patients and patients with Grade 4 glioma. Conclusion: The delivery of SLDR is feasible in patients with recurrent gliomas and resulted in improved outcomes for patients who underwent re-resection. There were 2 long-term survivors (>48 months). This pilot study supports the notion that reduced dose rate influences the efficacy and tolerance of reirradiation in the treatment of recurrent gliomas.

Siker, Malika L.; Firat, Selim Y. [Department of Radiation Oncology, Medical College of Wisconsin, Milwaukee, WI (United States); Mueller, Wade [Department of Neurosurgery, Medical College of Wisconsin, Milwaukee, WI (United States); Krouwer, Hendrikus [Department of Neurosurgery, Medical College of Wisconsin, Milwaukee, WI (United States); Department of Neurology, Medical College of Wisconsin, Milwaukee, WI (United States); Schultz, Christopher J., E-mail: cschultz@mcw.edu [Department of Radiation Oncology, Medical College of Wisconsin, Milwaukee, WI (United States); Department of Neurosurgery, Medical College of Wisconsin, Milwaukee, WI (United States)

2012-02-01T23:59:59.000Z

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81

Gamma Radiation Dose Rate in Air due to Terrestrial Radionuclides in Southern Brazil: Synthesis by Geological Units and Lithotypes Covered by the Serra do Mar Sul Aero?Geophysical Project  

Science Conference Proceedings (OSTI)

The absorbed dose rates in air due to terrestrial radionuclides were estimated from aerial gamma spectrometric data for an area of 48

Rodrigo O. Bastos; Carlos R. Appoloni; José P. P. Pinese

2008-01-01T23:59:59.000Z

82

Image  

NLE Websites -- All DOE Office Websites (Extended Search)

waste-Any of the various forms of high beta-gamma defense TRU waste 15 requiring remote-handling and with a surface dose rate exceeding 200 millirem per hour. 16 Standard...

83

Dose Coverage Beyond the Gross Tumor Volume for Various Stereotactic Body Radiotherapy Planning Techniques Reporting Similar Control Rates for Stage I Non-Small-Cell Lung Cancer  

SciTech Connect

Purpose: To investigate the dose falloff region for various stereotactic body radiotherapy (SBRT) planning techniques used in the treatment of Stage I non-small-cell lung cancer reporting similar control rates. Methods and Materials: The SBRT plans were constructed on five patient data sets using seven different planning regimens. These regimens varied in the number of beams, number of fractions, prescription target, and prescribed dose used. For each case all regimens were planned using a common gross tumor volume (GTV). To compare dose falloff for the various regimens, resulting physical dose grids were converted into normalized total dose (NTD) grids. Furthermore, to determine the potential coverage of microscopic extension of the various regimens minimal peripheral NTD (NTD-MP{sub 100}) were calculated and plotted as a function of incremental volume expansions of the GTV. Results: Average values for NTD-MP{sub 100} varied over a range of 174 Gy at the GTV periphery, but this range fell to 10 Gy at a distance of 14 mm from the GTV. Of 35 plans, 23 resulted in potential microscopic extension coverage of 78% to 95%. Averages for five of seven regimens fell within the range of 80% to 85%. Results were negligibly affected when intrafraction motion effects were accounted for. Conclusions: Although average NTD-MP{sub 100} varied dramatically at the GTV, periphery values became similar at a distance of 14 mm from the GTV. With the exception of two, potential coverage of microscopic extension was similar for all planning techniques, with averages falling within a 5% range.

Arvidson, Noah B. [Department of Medical Physics, University of Wisconsin, Madison, WI (United States); Mehta, Minesh P. [Department of Human Oncology, University of Wisconsin, Madison, WI (United States); Tome, Wolfgang A. [Department of Medical Physics, University of Wisconsin, Madison, WI (United States); Department of Human Oncology, University of Wisconsin, Madison, WI (United States)], E-mail: tome@humonc.wisc.edu

2008-12-01T23:59:59.000Z

84

Retrospective Analysis of Local Control and Cosmetic Outcome of 147 Periorificial Carcinomas of the Face Treated With Low-Dose Rate Interstitial Brachytherapy  

SciTech Connect

Purpose: Skin cancer is the most common malignancy in white populations. We evaluated the local cure rate and cosmetic outcome of patients with basal cell carcinoma (BCC) or squamous cell carcinoma (SCC) of the face treated with low-dose rate brachytherapy. Methods and Materials: Between February 1990 and May 2000, 147 facial carcinomas in 132 patients were treated by {sup 192}Ir wire implantation. Side effects of brachytherapy were noted. Follow-up was 2 years or more. Locoregional recurrence-free survival (LRFS) and overall survival were recorded. Group A included patients treated by primary brachytherapy, and Group B included those treated after recurrence. Results: A total of 121 carcinomas were BCCs (82.3%) and 26 were SCCs (17.7%); the median tumor size was 10 mm. Of the tumors, 86 (58.5%) were in men and 61 (41.5%) were in women; the median age was 71 years. Group A comprised 116 lesions (78.9%), and Group B, 31 (21.1%). There were 17 relapses (11.6%) after a median follow-up of 72 months: 12 local, 4 nodal, and 1 local and nodal. Locoregional-free survival was 96.6% at 2 years and 87.3% at 5 years. Five-year LRFS was 82.6% in men and 93.3% in women (p = 0.027). After adjustment for gender, LRFS was better after primary treatment than after recurrence (hasard ratio HR, 2.91; 95% confidence interval, 1.06-8.03; p = 0.039). Five-year LRFS was 90.4% for BCC and 70.8% for SCC (p = 0.03). There were no Grade 3 complications. Conclusions: Low-dose rate brachytherapy offers good local control and cosmetic outcome in patients with periorificial skin carcinomas, with no Grade 3 complications. Brchytherapy is more efficient when used as primary treatment.

Ducassou, Anne, E-mail: anned40@hotmail.com [Department of Radiation Oncology, Institut Claudius Regaud, Toulouse (France); David, Isabelle [Department of Radiation Oncology, Institut Claudius Regaud, Toulouse (France); Filleron, Thomas [Department of Biostatistics, Institut Claudius Regaud, Toulouse (France); Rives, Michel; Bonnet, Jacques; Delannes, Martine [Department of Radiation Oncology, Institut Claudius Regaud, Toulouse (France)

2011-11-01T23:59:59.000Z

85

Lung cancer mortality between 1950 and 1987 after exposure to fractionated moderate-dose-rate ionizing radiation in the Canadian fluoroscopy cohort study and a comparison with lung cancer mortality in the atomic bomb survivors study  

Science Conference Proceedings (OSTI)

Current lung cancer risk estimates after exposure to low-linear energy transfer radiation such as X rays are based on studies of people exposed to such radiation at high dose rates, for example the atomic bomb survivors. Radiobiology and animal experiments suggest that risks from exposure at low to moderate dose rates, for example medical diagnostic procedures, may be overestimated by such risk models, but data for humans to examine this issue are limited. In this paper we report on lung cancer mortality between 1950 and 1987 in a cohort of 64,172 Canadian tuberculosis patients, of whom 39% were exposed to highly fractionated multiple chest fluoroscopies leading to a mean lung radiation dose of 1.02 Sv received at moderate dose rates. These data have been used to estimate the excess relative risk per sievert of lung cancer mortality, and this is compared directly to estimates derived from 75,991 atomic bomb survivors. Based on 1,178 lung cancer deaths in the fluoroscopy study, there was no evidence of any positive association between risk and dose, with the relative risk at 1 Sv being 1.00 (95% confidence interval 0.94, 1.07), which contrasts with that based on the atomic bomb survivors, 1.60 (1.27, 1.99). The difference in effect between the two studies almost certainly did not arise by chance (P = 0.0001). This study provides strong support from data for humans for a substantial fractionation/dose-rate effect for low-linear energy transfer radiation and lung cancer risk. This implies that lung cancer risk from exposures to such radiation at present-day dose rates is likely to be lower than would be predicted by current radiation risk models based on studies of high-dose-rate exposures. 25 refs., 8 tabs.

Howe, G.R. [Univ. of Toronto, Ontario (Canada)

1995-06-01T23:59:59.000Z

86

Gamma Radiation Dose Rate in Air due to Terrestrial Radionuclides in Southern Brazil: Synthesis by Geological Units and Lithotypes Covered by the Serra do Mar Sul Aero-Geophysical Project  

SciTech Connect

The absorbed dose rates in air due to terrestrial radionuclides were estimated from aerial gamma spectrometric data for an area of 48,600 km{sup 2} in Southern Brazil. The source data was the Serra do Mar Sul Aero-Geophysical Project back-calibrated in a cooperative work among the Geological Survey of Brazil, the Geological Survey of Canada, and Paterson, Grant and Watson Ltd. The concentrations of eU (ppm), eTh (ppm) and K (%) were converted to dose rates in air (nGy{center_dot}h{sup -1}) by accounting for the contribution of each element's concentration. Regional variation was interpreted according to lithotypes and a synthesis was performed according to the basic geological units present in the area. Higher values of total dose were estimated for felsic igneous and metamorphic rocks, with average values varying up to 119{+-}24 nGy{center_dot}h{sup -1}, obtained by Anitapolis syenite body. Sedimentary, metasedimentary and metamafic rocks presented the lower dose levels, and some beach deposits reached the lowest average total dose, 18.5{+-}8.2 nGy{center_dot}h{sup -1}. Thorium gives the main average contribution in all geological units, the highest value being reached by the nebulitic gneisses of Atuba Complex, 71{+-}23 nGy{center_dot}h{sup -1}. Potassium presents the lowest average contribution to dose rate in 53 of the 72 units analyzed, the highest contribution being obtained by intrusive alkaline bodies (28{+-}12 nGy{center_dot}h{sup -1}). The general pattern of geographic dose distribution respects well the hypotheses on geo-physicochemical behavior of radioactive elements.

Bastos, Rodrigo O.; Appoloni, Carlos R. [Applied Nuclear Physics Laboratory-Department of Physics-CCE State University of Londrina Campus Universitario-Rodovia Celso Garcia Cid s/n, Cx. Postal 6001, CEP 86051-990, Londrina, PR (Brazil); Pinese, Jose P. P. [Department of Geosciences-CCE State University of Londrina Campus Universitario-Rodovia Celso Garcia Cid s/n, Cx. Postal 6001, CEP 86051-990, Londrina, PR (Brazil)

2008-08-07T23:59:59.000Z

87

NIST: Comparison of Co60 Absorbed Dose for High-Dose ...  

Science Conference Proceedings (OSTI)

... at the dose levels used in radiation processing were ... 1 to 2 parts in 10 2 . The dose-rate effect ... doses for the laboratories that used low-rate gamma ...

2013-03-13T23:59:59.000Z

88

SCIENTIFIC CORRESPONDENCE Radiation doses  

E-Print Network (OSTI)

-- ation doses and cancer rates to the workers m the first Soviet atom-bomb facility, near 2 Chelyabinsk-dose groups. Unfortunately, they did not report the number in the workforce. Pending release of the full data' Forschungsergebmsse All (1972). 2.Hunter J. R.. Unesco Reports m Marine Soence 28, (1984). 3. Hassan. E. M. & Hassan

Shlyakhter, Ilya

89

Low Dose Radiation Research Program: Aloke Chatterjee  

NLE Websites -- All DOE Office Websites (Extended Search)

Chatterjee, A. and Holley, W.R. 1999 Workshop: Biological Effects of Low-Dose and Low-Dose-Rate Radiation Exposures: An Integrated Theoretical and Experimental Approach....

90

Prospective Multi-Institutional Study of Definitive Radiotherapy With High-Dose-Rate Intracavitary Brachytherapy in Patients With Nonbulky (<4-cm) Stage I and II Uterine Cervical Cancer (JAROG0401/JROSG04-2)  

SciTech Connect

Purpose: To determine the efficacy of a definitive radiotherapy protocol using high-dose-rate intracavitary brachytherapy (HDR-ICBT) with a low cumulative dose schedule in nonbulky early-stage cervical cancer patients, we conducted a prospective multi-institutional study. Methods and Materials: Eligible patients had squamous cell carcinoma of the intact uterine cervix, Federation of Gynecologic Oncology and Obstetrics (FIGO) stages Ib1, IIa, and IIb, tumor size <40 mm in diameter (assessed by T2-weighted magnetic resonance imaging), and no pelvic/para-aortic lymphadenopathy. The treatment protocol consisted of whole-pelvis external beam radiotherapy (EBRT) of 20 Gy/10 fractions, pelvic EBRT with midline block of 30 Gy/15 fractions, and HDR-ICBT of 24 Gy/4 fractions (at point A). The cumulative biologically effective dose (BED) was 62 Gy{sub 10} ({alpha}/{beta} = 10) at point A. The primary endpoint was the 2-year pelvic disease progression-free (PDPF) rate. All patients received a radiotherapy quality assurance review. Results: Between September 2004 and July 2007, 60 eligible patients were enrolled. Thirty-six patients were assessed with FIGO stage Ib1; 12 patients with stage IIa; and 12 patients with stage IIb. Median tumor diameter was 28 mm (range, 6-39 mm). Median overall treatment time was 43 days. Median follow-up was 49 months (range, 7-72 months). Seven patients developed recurrences: 3 patients had pelvic recurrences (2 central, 1 nodal), and 4 patients had distant metastases. The 2-year PDPF was 96% (95% confidence interval [CI], 92%-100%). The 2-year disease-free and overall survival rates were 90% (95% CI, 82%-98%) and 95% (95% CI, 89%-100%), respectively. The 2-year late complication rates (according to Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer of Grade {>=}1) were 18% (95% CI, 8%-28%) for large intestine/rectum, 4% (95% CI, 0%-8%) for small intestine, and 0% for bladder. No Grade {>=}3 cases were observed for genitourinary/gastrointestinal late complications. Conclusions: These results suggest that definitive radiotherapy using HDR-ICBT with a low cumulative dose schedule (BED, 62 Gy{sub 10} at point A) can provide excellent local control without severe toxicity in nonbulky (<4-cm) early-stage cervical cancer.

Toita, Takafumi, E-mail: b983255@med.u-ryukyu.ac.jp [Department of Radiology, Graduate School of Medical Science, University of Ryukyus, Okinawa (Japan); Kato, Shingo [Research Center for Charged Particle Therapy, National Institute of Radiological Sciences, Chiba (Japan); Niibe, Yuzuru [Department of Radiology, School of Medicine, Kitasato University, Sagamihara (Japan); Ohno, Tatsuya [Gunma University Heavy Ion Medical Center, Maebashi (Japan); Kazumoto, Tomoko [Department of Radiology, Saitama Cancer Center, Saitama (Japan); Kodaira, Takeshi [Department of Radiation Oncology, Aichi Cancer Center, Nagoya (Japan); Kataoka, Masaaki [Department of Radiology, National Shikoku Cancer Center, Ehime (Japan); Shikama, Naoto [Department of Radiation Oncology, Saku Central Hospital, Saku (Japan); Kenjo, Masahiro [Department of Radiation Oncology, Graduate School of Medical Science, Hiroshima University, Hiroshima (Japan); Tokumaru, Sunao [Department of Radiology, Saga University, Saga (Japan); Yamauchi, Chikako [Department of Radiation Oncology, Shiga Medical Center for Adults, Moriyama (Japan); Suzuki, Osamu [Department of Radiation Oncology, Osaka Medical Center for Cancer, Osaka (Japan); Sakurai, Hideyuki [Proton Medical Research Center and Tsukuba University, Tsukuba (Japan); Numasaki, Hodaka; Teshima, Teruki [Department of Medical Physics and Engineering, Graduate School of Medicine, Osaka University, Suita, Osaka (Japan); Oguchi, Masahiko [Department of Radiation Oncology, Cancer Institute Hospital, Tokyo (Japan); Kagami, Yoshikazu [Radiation Oncology Division, National Cancer Center Hospital, Tokyo (Japan); Nakano, Takashi [Department of Radiation Oncology, Gunma University, Graduate School of Medicine, Maebashi (Japan); Hiraoka, Masahiro [Department of Radiation Oncology and Image-applied Therapy, Kyoto University, Graduate School of Medicine, Kyoto (Japan); Mitsuhashi, Norio [Department of Radiation Oncology, Tokyo Women's Medical University, Tokyo (Japan)

2012-01-01T23:59:59.000Z

91

Low Dose Radiation Research Program: Glossary  

NLE Websites -- All DOE Office Websites (Extended Search)

Glossary Glossary A B C D E F G H I J K L M N O P Q R S T U V W X Y Z We welcome updates to the glossary. Please send them to Low Dose. A α=β Ratio: A measure of the curvature of the cell survival curve and a measure of the sensitivity of a tissue or tumor to dose fractionation. The dose at which the linear and quadratic components of cell killing are equal. Abscopal Effect: The radiation response in tissue at a distance from the irradiated site invoked by local irradiation. Absorbed Dose Rate: Absorbed dose divided by the time it takes to deliver that dose. High dose rates are usually more damaging to humans and animals than low-dose rates. This is because repair of damage is more efficient when the dose rate is low. Absorbed Dose: The amount of energy deposited in any substance by ionizing

92

An Absorbed-Dose/Dose-Rate Dependence for the Alanine ...  

Science Conference Proceedings (OSTI)

... Natl. Inst. Stand. Technol. 99, 121-141 (1994). [3] JC Humphreys, JM Puhl, SM Seltzer, WL McLaughlin, MF Desrosiers, DL Bensen, and ML Walker ...

2008-05-06T23:59:59.000Z

93

Dose algorithm for EXTRAD 4100S extremity dosimeter for use at Sandia National Laboratories.  

SciTech Connect

An updated algorithm for the EXTRAD 4100S extremity dosimeter has been derived. This algorithm optimizes the binning of dosimeter element ratios and uses a quadratic function to determine the response factors for low response ratios. This results in lower systematic bias across all test categories and eliminates the need for the 'red strap' algorithm that was used for high energy beta/gamma emitting radionuclides. The Radiation Protection Dosimetry Program (RPDP) at Sandia National Laboratories uses the Thermo Fisher EXTRAD 4100S extremity dosimeter, shown in Fig 1.1 to determine shallow dose to the extremities of potentially exposed individuals. This dosimeter consists of two LiF TLD elements or 'chipstrates', one of TLD-700 ({sup 7}Li) and one of TLD-100 (natural Li) separated by a tin filter. Following readout and background subtraction, the ratio of the responses of the two elements is determined defining the penetrability of the incident radiation. While this penetrability approximates the incident energy of the radiation, X-rays and beta particles exist in energy distributions that make determination of dose conversion factors less straightforward in their determination.

Potter, Charles Augustus

2011-05-01T23:59:59.000Z

94

Low Dose Radiation Research Program: Genomic Instability and...  

NLE Websites -- All DOE Office Websites (Extended Search)

Genomic Instability and Low Dose Low Dose Rate Radiation. Authors: Lei Huang, Suzanne Grim, William F. Morgan Institutions: University of Maryland. Humans will always receive...

95

Beta Gamma Fine Fully Lamellar Materials: Breaking Ductility and ...  

Science Conference Proceedings (OSTI)

Composition Design of Multi-Component ?-Ti Alloys Based on a Cluster Model ... Product Forms Using Blended-Elemental Powder-Based Ti-6AL-4V Alloy ... Rheological Properties of Feedstock Composed of Titanium Alloy Powder and ...

96

Low Dose Radiation Research Program: Kenneth T. Bogen  

NLE Websites -- All DOE Office Websites (Extended Search)

T. Bogen Lawrence Livermore National Laboratory Technical Abstracts 2002 Workshop: Low-dose dose-response of proliferating human cells exposed to low dose rate g-radiation. Enns,...

97

Internal Dose Estimates from  

E-Print Network (OSTI)

Appendix F Internal Dose Estimates from NTS Fallout F-1 #12;Radiation Dose to the Population...........................................................................................40 Comparison to dose estimates from global fallout

98

Low Dose Radiation Research Program: Low-Dose Dose-Response of  

NLE Websites -- All DOE Office Websites (Extended Search)

Low-Dose Dose-Response of Proliferating Human Cells Exposed to Low Low-Dose Dose-Response of Proliferating Human Cells Exposed to Low Dose Rate g-Radiation. Authors: Louise Enns,1 Michael Weinfeld,1 Albert Murtha,1 and Kenneth Bogen2 Institutions: 1Cross Cancer Institute and 2Lawrence Livermore National Laboratory. Clinical and environmental exposure to ionizing radiation rarely exceeds 200 cGy. To examine cell proliferation at early times (up to 5 days) post-irradiation, we are utilizing an assay in which single cells encapsulated within ~30- to 70-µm-diameter agarose gel microdrops (GMDs) are exposed and cultured for 4 days at 37°C, then analyzed by flow cytometry (FC). Clonogenic proliferation is measured as the fraction of occupied GMDs containing multicellular microcolonies after 4 days in culture. This assay was applied to human A549 lung cells exposed to gamma

99

Low Dose Suppression of Neoplastic Transformation in Vitro  

SciTech Connect

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.

John Leslie Redpath

2012-05-01T23:59:59.000Z

100

Secondary Doses in Anthropomorphic Phantoms Irradiated with Light Ion Beams  

Science Conference Proceedings (OSTI)

Dose/Dose Rate / Special Issue on the 11th International Conference on Radiation Shielding and the 15th Topical Meeting of the Radiation Protection and Shielding Division (Part 1) / Radiation Protection

Martha Hultqvist; Irena Gudowska

Note: This page contains sample records for the topic "beta-gamma dose rates" from the National Library of EnergyBeta (NLEBeta).
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101

Low Dose Radiation  

NLE Websites -- All DOE Office Websites (Extended Search)

Ancient Salt Beds 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 thrive if they grew up without their constant exposure to background radiation? That's what a consortium of scientists conducting an experiment at the Waste Isolation Pilot Plant aim to find out. Despite being an underground repository for transuranic radioactive waste,

102

Low Dose Radiation Research Program: Michael Weil  

NLE Websites -- All DOE Office Websites (Extended Search)

Dubrova, Y., Weil, M., and Brenner, D. H2AX Foci after Low Dose-Rate Irradiation Reveal a Defect in DNA DSB Processing in Cells from Unaffected Parents of...

103

Low Dose Radiation Research Program: Proteomic and Biochemical...  

NLE Websites -- All DOE Office Websites (Extended Search)

proteomic changes including protein expression levels and post-translational modification due to low dose-rate ionizing radiation Expected Outcomes Increased differentiation...

104

Mouse Strain-Dependent Variations in Sensitivity to Induction of Gamma-H2AX Foci after Continuous Low Dose-Rate Irradiation: The Atm-/- vs Atm +/+ genotypes on Balb/c, 129S6, C57BL/6J, and A/J inbred strains  

NLE Websites -- All DOE Office Websites (Extended Search)

Mouse Strain-Dependent Variations in Sensitivity to Induction of Gamma-H2AX Foci Mouse Strain-Dependent Variations in Sensitivity to Induction of Gamma-H2AX Foci after Continuous Low Dose-Rate Irradiation: The Atm-/- vs Atm +/+ genotypes on Balb/c, 129S6, C57BL/6J, and A/J inbred strains. J.R.Brogan 1 , H. Nagasawa 1 , T.A Kato 1 , C.Fallgren 1 , T.Wade 1 . P.Genik 1 , J.B.Little 2 , J.S.Bedford 1 , and M.M.Weil 1 1 Department of Environmental and Radiological Health Sciences, Colorado State University, Fort Collins, CO 80523; 2 Department of Genetics and Complex Diseases, Harvard School of Public Health, Boston MA 02115 We have recently developed a 'low dose rate' gamma-H2AX assay that is sufficiently sensitive to distinguish differences in response for cells from normal Atm +/+ (mouse) or ATM+/+ (human) and the phenotypes associated with the corresponding

105

Low Dose Radiation Research Program: National Laboratories  

NLE Websites -- All DOE Office Websites (Extended Search)

National Laboratories National Laboratories The Low Dose Radiation Program funding encompasses several Scientific Focus Areas (SFAs). The SFAs fund merit-reviewed research at DOE national laboratories. This management approach was created in 2008 by the Office of Biological and Environmental Research (BER) within the U.S. Department of Energy's (DOE's) Office of Science. PNNL's Low Dose Radiation Research Program Scientific Focus Area Linear and Nonlinear Tissue-Signaling Mechanisms in Response to Low Dose and Low Dose-Rate Radiation This program is funded as a U.S. Department of Energy Scientific Focus Area (SFA), and is an integrated cooperative program to understand low dose radiation effects in a complex model system. Coordinating Multidisciplinary Expertise The SFAs are designed to take advantage of the multidisciplinary,

106

Low Dose Radiation Research Program: Universities  

NLE Websites -- All DOE Office Websites (Extended Search)

Universities Universities | Duke University | Loma Linda University | Northwestern University | University of Chicago | University of California Davis | Northwestern University University of Chicago University of California Davis Effects of Low Dose Irradiation on NF-κB Signaling Networks and Mitochondria Principal Investigator: Dr. Gayle Woloschak DOE Low Dose Research Program Projects Low dose-low dose rate irradiation leads to long term changes in numbers of mitochondria and mitochondrial genomes - Principal Investigator: Gayle Woloschak, Professor, Department of Radiation Oncology, Northwestern University, Chicago, IL, USA NF-κB-mediated pro-survival network in low dose radiation-induced adaptive protection - Principal Investigator: Jian Jian Li, Professor, Department of Radiation Oncology, University of California Davis, Davis,

107

Low Dose Radiation Program: Workshop VI Abstracts  

NLE Websites -- All DOE Office Websites (Extended Search)

Workshop VI Principal Investigator and Abstracts Workshop VI Principal Investigator and Abstracts Anderson, Carl Whole Genome Analysis of Functional Protein Binding Sites and DNA Methylation: Application to p53 and Low Dose Ionizing Radiation. Averbeck, Dietrich Cellular Responses at Low Doses of Ionizing Radiation. Azzam, Edouard Adaptive Responses to Low Dose/Low Dose-Rate ?-Rays in Normal Human Fibroblasts: The Role of Oxidative Metabolism. Bailey, Susan The Role of Telomere Dysfunction in Driving Genomic Instability. Balajee, Adayabalam Low Dose Radiation Induced DNA Damage Signaling and Repair Responses in Human 3-Dimensional Skin Model System. Barcellos-Hoff, Mary Helen Imaging Bioinformatics for Mapping Multidimensional Responses. Barcellos-Hoff, Mary Helen Biological Response to Radiation Mediated through the Microenvironment and

108

High-Dose Dosimetry  

Science Conference Proceedings (OSTI)

... web page below. Service descriptions and price schedule for NIST high-dose services are found in this link. The intention ...

2013-03-01T23:59:59.000Z

109

Rate Schedules  

Energy.gov (U.S. Department of Energy (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...

110

Boiling Water Reactor Shutdown Chemistry and Dose Summary: September 2010  

Science Conference Proceedings (OSTI)

This 2010 update provides an annual report of shutdown radiation dose rates at 46 boiling water reactors (BWRs) that participate in the Electric Power Research Institute's (EPRI's) BWR Chemistry Monitoring and Assessment program and supersedes the BWR Radiation Assessment and Control (BRAC) Summary that was issued twice a year. In addition to BRAC dose rates, the report also includes information on operating and shutdown water chemistry and worker outage dose and contamination.

2010-09-23T23:59:59.000Z

111

Rates - WAPA-137 Rate Order  

NLE Websites -- All DOE Office Websites (Extended Search)

WAPA-137 Rate Order WAPA-137 Rate Order 2009 CRSP Management Center Customer Rates Second Step Presentation from the June 25, 2009, Customer Meeting Handout Materials from the June 25, 2009, Customer Meeting Customer Comment Letters ATEA CREDA Farmington ITCA AMPUA Rate Adjustment Information The second step of WAPA-137 SLCA/IP Firm Power, CRSP Transmission and Ancillary Services rate adjustment. FERC Approval of Rate Order No. WAPA-137 Notice Of Filing for Rate Order No. WAPA-137 Published Final FRN for Rate Order No. WAPA-137 Letter to Customers regarding the published Notice of Extension of Public Process for Rate Order No. WAPA-137 Published Extension of Public Process for Rate Order No. WAPA-137 FRN Follow-up Public Information and Comment Forum Flier WAPA-137 Customer Meetings and Rate Adjustment Schedule

112

Energy Rating  

E-Print Network (OSTI)

Consistent, accurate, and uniform ratings based on a single statewide rating scale Reasonable estimates of potential utility bill savings and reliable recommendations on cost-effective measures to improve energy efficiency Training and certification procedures for home raters and quality assurance procedures to promote accurate ratings and to protect consumers Labeling procedures that will meet the needs of home buyers, homeowners, renters, the real estate industry, and mortgage lenders with an interest in home energy ratings

Cabec Conference; Rashid Mir P. E

2009-01-01T23:59:59.000Z

113

Insertion Rates  

Science Conference Proceedings (OSTI)

HOME > Insertion Rates. TECH HEADLINES. Research Explores a New Layer in Additive Manufacturin... Grand Opening Slated for Electron Microscopy Facility.

114

Low Dose Radiation Research Program: Original Research Program Plan  

NLE Websites -- All DOE Office Websites (Extended Search)

Original Research Program Plan Original Research Program Plan Biological Effects of Low Dose and Dose Rate Radiation Prepared for the Office of Biological and Environmental Research by The Low Dose Radiation Research Program Plan Subcommittee of the Biological and Environmental Research Advisory Committee. II. Table of Contents Face Page Table of Contents Executive Summary Introduction Program Outline Low Dose Radiation vs. Endogenous Oxidative Damage - The Same or Different? Key Question Description Decision Making Value Recommendations and Costs Understanding Biological Responses to Radiation And Endogenous Damage Key Question Description Decision Making Value Recommendations and Costs Thresholds for Low Dose Radiation - Fact or Fiction? Key Question Description Decision Making Value Recommendations and Costs

115

Rate schedule  

NLE Websites -- All DOE Office Websites (Extended Search)

Firm Power Service Provided by Rate/Charges Firm Power Service Provided by Rate/Charges Rate/Charges Effective Through (or until superceded) Firm Sales (SLIP-F9) Composite Rate SLIP 29.62 mills/kWh 9/30/2015 Demand Charge SLIP $5.18/kW-month 9/30/2015 Energy Charge SLIP 12.19 mills/kWh 9/30/2015 Cost Recovery Charge (CRC) SLIP 0 mills/kWh 9/30/2015 Transmission Service Provided by Current Rates effective10/12 - 9/15 (or until superceded) Rate Schedule Effective Through Firm Point-to-Point Transmission (SP-PTP7) CRSP $1.14 per kW-month $13.69/kW-year $0.00156/kW-hour $0.04/kW-day $0.26/kW-week 10/1/2008-9/30/2015 Network Integration Transmission (SP-NW3) CRSP see rate schedule 10/1/2008-9/30/2015 Non-Firm Point-to-Point Transmission (SP-NFT6) CRSP see rate schedule 10/1/2008-9/30/2015 Ancillary Services Provided by Rate Rate Schedule

116

Imaging method for monitoring delivery of high dose rate brachytherapy  

Science Conference Proceedings (OSTI)

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.

Weisenberger, Andrew G; Majewski, Stanislaw

2012-10-23T23:59:59.000Z

117

Gamma Dose Rate Near a New 252Cf Brachytherapy Source  

Science Conference Proceedings (OSTI)

Technical Paper / Special Issue on the 16th Biennial Topical Meeting of the Radiation Protection and Shielding Division / Radiation Transport and Protection

Eugene C. Fortune IV; Ian C. Gauld; C.-K. Chris Wang

118

Internal Dose Assessment (IDA) Spreadsheet  

Science Conference Proceedings (OSTI)

The purpose of the Internal Dose Assessment (IDA) Spreadsheet is to calculate internal occupational dose following the methodology described in the EPRI Alpha Monitoring Guidelines.

2007-04-12T23:59:59.000Z

119

Low Dose Radiation Research Program: Bruce E. Lehnert  

NLE Websites -- All DOE Office Websites (Extended Search)

E. Lehnert E. Lehnert Los Alamos National Laboratory Past Project Low Dose Ionizing Radiation-Induced Effects in Irradiated and Unirradiated Cells: Pathways Analysis in Support of Risk Assessment. Technical Abstracts 2002 Workshop: Low Dose Ionizing Radiation-Induced Effects in Irradiated and Unirradiated cells: Pathways Analysis in Support of Risk Assessment. Lehnert, B.E., Cary, R., Gadbois, D. and Gupta G. 2001 Workshop: Low Dose, Low Dose Rate Effects of Ionizing Radiation in Irradiated and Unirradiated Cells. Lehnert, B.E. 1999 Workshop: Low Dose, Low Dose Rate Effects of Ionizing Radiation in Irradiated and Unirradiated Cells. Lehnert, B.E. Publications Lehnert, B.E., Radiation bystander effects. U.S.Department of Energy Research News (March 6 issue) Goldberg, Z. and Lehnert, B.E. (2002). Radiation-induced effects in

120

Dose Reduction Techniques  

SciTech Connect

As radiation safety specialists, one of the things we are required to do is evaluate tools, equipment, materials and work practices and decide whether the use of these products or work practices will reduce radiation dose or risk to the environment. There is a tendency for many workers that work with radioactive material to accomplish radiological work the same way they have always done it rather than look for new technology or change their work practices. New technology is being developed all the time that can make radiological work easier and result in less radiation dose to the worker or reduce the possibility that contamination will be spread to the environment. As we discuss the various tools and techniques that reduce radiation dose, keep in mind that the radiological controls should be reasonable. We can not always get the dose to zero, so we must try to accomplish the work efficiently and cost-effectively. There are times we may have to accept there is only so much you can do. The goal is to do the smart things that protect the worker but do not hinder him while the task is being accomplished. In addition, we should not demand that large amounts of money be spent for equipment that has marginal value in order to save a few millirem. We have broken the handout into sections that should simplify the presentation. Time, distance, shielding, and source reduction are methods used to reduce dose and are covered in Part I on work execution. We then look at operational considerations, radiological design parameters, and discuss the characteristics of personnel who deal with ALARA. This handout should give you an overview of what it takes to have an effective dose reduction program.

WAGGONER, L.O.

2000-05-16T23:59:59.000Z

Note: This page contains sample records for the topic "beta-gamma dose rates" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


121

Low Dose Radiation Research Program: William F. Morgan  

NLE Websites -- All DOE Office Websites (Extended Search)

William F. Morgan William F. Morgan Pacific Northwest National Laboratory PO Box 999 Richland, Washington About this Project Projects Using a Low LET Electron Microbeam to Investigate Non-Targeted Effects of Low Dose Radiation. Optimizing the Scientific, Regulatory, and Societal Impact of the DOE Low Dose Radiation Research Program A Mechanistic Study of the Radiation Quality Dependence of Bystander Effects in Human Cells. Genetic Factors Affecting Susceptibility to Low-Dose Radiation Mechanisms of Adaptive Responses and Genomic Instability Induced by Low Dose/ Low Dose Rate Radiation Technical Abstracts 2006 Workshop: Using a Low-LET Electron Microbeam to Investigate Non-Targeted Effects of Low Dose Radiation Sowa, M.B., Goetz, W., Baulch, J., and Morgan, W.F. Genetic Factors Affecting Susceptibility to Low-Dose Radiation

122

Low Dose Radiation Research Program: Linking Molecular Events to Cellular  

NLE Websites -- All DOE Office Websites (Extended Search)

Linking Molecular Events to Cellular Responses at Low Dose Exposures Linking Molecular Events to Cellular Responses at Low Dose Exposures Thomas Weber Pacific Northwest National Laboratory Why This Project It currently costs billions of dollars to protect workers and the public from exposure to man-made radiation, despite exposure levels lower than the natural background levels of radiation. If it could be demonstrated that there is no increased cancer risk associated with these low dose exposures, these resources could be directed toward more critical societal issues. Defining low dose radiation cancer risks is limited by our ability to measure and directly correlate relevant cellular and molecular responses occurring at the low radiation dose and dose rate with tumor formation. This deficiency has led to conservative risk assessments based on low dose

123

External Dose Estimates from  

E-Print Network (OSTI)

Appendix E External Dose Estimates from NTS Fallout E-1 #12;External Radiation Exposure as the dependence on fallout time of arrival. The most exposed individuals were outdoor workers; the least exposed was about a factor of 20 less than that from "global fallout" from high- yield weapons tests carried out

124

External Dose Estimates from  

E-Print Network (OSTI)

Appendix G External Dose Estimates from Global Fallout G-1 #12;External Radiation Exposure from the fallout from all of these tests was about 0.7 mSv, about equivalent to 2-3 years of external radiation exposure from natural background. In contrast to the fallout from tests at the Nevada Test site

125

Rates and Repayment Services  

NLE Websites -- All DOE Office Websites (Extended Search)

Tariff Rates FY 2014 Rates and Rate Schedules FY 2013 Rates and Rate Schedules FY 2012 Rates and Rate Schedules FY 2011 Rates and Rate Schedules FY 2010 Rates and Rate Schedules FY...

126

When is a dose not a dose  

Science Conference Proceedings (OSTI)

Although an enormous amount of progress has been made in the fields of radiation protection and risk assessment, a number of significant problems remain. The one problem which transcends all the rest, and which has been subject to considerable misunderstanding, involves what has come to be known as the 'linear non-threshold hypothesis', or 'linear hypothesis'. Particularly troublesome has been the interpretation that any amount of radiation can cause an increase in the excess incidence of cancer. The linear hypothesis has dominated radiation protection philosophy for more than three decades, with enormous financial, societal and political impacts and has engendered an almost morbid fear of low-level exposure to ionizing radiation in large segments of the population. This document presents a different interpretation of the linear hypothesis. The basis for this view lies in the evolution of dose-response functions, particularly with respect to their use initially in the context of early acute effects, and then for the late effects, carcinogenesis and mutagenesis. 11 refs., 4 figs. (MHB)

Bond, V.P.

1991-01-01T23:59:59.000Z

127

Interspecies Scaling of Self-Organ Doses from a Voxel Mouse to Voxel Humans  

Science Conference Proceedings (OSTI)

Dose/Dose Rate / Special Issue on the 11th International Conference on Radiation Shielding and the 15th Topical Meeting of the Radiation Protection and Shielding Division (Part 1) / Radiation Protection

Sakae Kinase; Shinpei Matsuhashi; Kimiaki Saito

128

Integrated beta and gamma radiation dose calculations for the ferrocyanide waste tanks  

SciTech Connect

This report contains the total integrated beta and gamma radiation doses in all the ferrocyanide waste tanks. It also contains estimated gamma radiation dose rates for all single-shell waste tanks containing a liquid observation well.

Parra, S.A.

1994-11-30T23:59:59.000Z

129

Electron Dose Kernels to Account for Secondary Particle Transport in Deterministic Simulations  

Science Conference Proceedings (OSTI)

Dose/Dose Rate / Special Issue on the 11th International Conference on Radiation Shielding and the 15th Topical Meeting of the Radiation Protection and Shielding Division (PART 3) / Radiation Protection

Ahmad K. Al-Basheer; Glenn E. Sjoden; Monica Ghita

130

Reducing Stray Radiation Dose for a Pediatric Patient Receiving Proton Craniospinal Irradiation  

Science Conference Proceedings (OSTI)

Dose/Dose Rate / Special Issue on the 11th International Conference on Radiation Shielding and the 15th Topical Meeting of the Radiation Protection and Shielding Division (Part 1) / Radiation Protection

Phillip J. Taddei; Dragan Mirkovic; Jonas D. Fontenot; Annelise Giebeler; Yuanshui Zheng; Uwe Titt; Shiao Woo; Wayne D. Newhauser

131

Necrosis and Apoptosis in Hepatocellular Carcinoma Following Low-Dose Versus High-Dose Preoperative Chemoembolization  

Science Conference Proceedings (OSTI)

Our purpose was to study necrosis and apoptosis of hepatocellular carcinoma (HCC) cells after preoperative transcatheter arterial chemoembolization (TACE) with use of low-dose and high-dose anticancer drugs in HCCs. Fifty-four patients with advanced but surgically resectable HCC were studied. Thirty-four patients who elected to undergo preoperative superselective TACE were randomized to low- and high-dose TACE. Patients in group A (n = 16) received low-dose anticancer drugs: 2 mg mitomycin C (MMC), 10 mg epirubicin (EPI), and 100 mg carboplatin (CBP). Patients in group B (n = 18) were given high doses of anticancer drugs (10 mg MMC, 40 mg EPI, and 300 mg CBP). Hepatic resection was subsequently performed. Group C comprised 20 patients who underwent resection without TACE. In all patients the necrosis rates and apoptosis index of tumor cells were evaluated by pathologic examinations and terminal deoxynucleotidyl transferase-mediated nick-end labeling assay. There was no significant difference between group A and group B in tumor response (p > 0.05) after TACE. Necrosis rates in groups A, B, and C were 88.4 {+-} 11.1%, 87.1 {+-} 12.5%, and 7.3 {+-} 3.5%, respectively. There was no significant difference between group A and group B (p > 0.05), while statistical difference was found between group A and group C (p 0.05). In conclusion, superselective TACE with low- and high-dose chemotherapeutic agents induced similar degrees of cellular apoptosis and necrosis.

Lu Wei, E-mail: dr-lw@163.com; Li Yanhao, E-mail: liyanhao@fimmu.com; He Xiaofeng; Zhao Jianbo; Chen Yong; Mei Quelin [Southern Medical University, Department of Interventional Radiology, Nanfang Hospital (China)

2008-11-15T23:59:59.000Z

132

Occupational dose estimates for a monitored retrievable storage facility  

SciTech Connect

Occupational doses were estimated for radiation workers at the monitored retrievable storage (MRS) facility. This study provides an estimate of the occupational dose based on the current MRS facility design, examines the extent that various design parameters and assumptions affect the dose estimates, and identifies the areas and activities where exposures can be reduced most effectively. Occupational doses were estimated for both the primary storage concept and the alternate storage concept. The dose estimates indicate the annual dose to all radiation workers will be below the 5 rem/yr federal dose equivalent limit. However, the estimated dose to most of the receiving and storage crew (the workers responsible for the receipt, storage, and surveillance of the spent fuel and its subsequent retrieval), to the crane maintenance technicians, and to the cold and remote maintenance technicians is above the design objective of 1 rem/yr. The highest annual dose is received by the riggers (4.7 rem) in the receiving and storage crew. An indication of the extent to which various design parameters and assumptions affect the dose estimates was obtained by changing various design-based assumptions such as work procedures, background dose rates in radiation zones, and the amount of fuel received and stored annually. The study indicated that a combination of remote operations, increased shielding, and additional personnel (for specific jobs) or changes in operating procedures will be necessary to reduce worker doses below 1.0 rem/yr. Operations that could be made at least partially remote include the removal and replacement of the tiedowns, impact limiters, and personnel barriers from the shipping casks and the removal or installation of the inner closure bolts. Reductions of the background dose rates in the receiving/shipping and the transfer/discharge areas may be accomplished with additional shielding.

Harty, R.; Stoetzel, G.A.

1986-06-01T23:59:59.000Z

133

Agriculture-related radiation dose calculations  

SciTech Connect

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.

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

1987-10-01T23:59:59.000Z

134

Development Pathways to Low-Cost Engineering Beta Gamma TiAl ...  

Science Conference Proceedings (OSTI)

About this Abstract. Meeting, 2010 TMS Annual Meeting & Exhibition. Symposium , Cost-Affordable Titanium III. Presentation Title, Development Pathways to ...

135

The DOE Automated Radioxenon Sampler-Analyzer (ARSA) Beta-Gamma Coincidence Spectrometer Data Analyzer  

Science Conference Proceedings (OSTI)

The ARSA developed at PNNL for the CTBT measures four radioxenon isotopes. This paper will describe the software program along with data formats, various software controllable parameters and calculations.

Heimbigner, Tom R.; Bowyer, Ted W.; McIntyre, Justin I.; Abel, Keith H.; Hayes, James C.; Panisko, Mark E.; Pitts, W. K.

2000-09-01T23:59:59.000Z

136

World Sheet Commuting beta-gamma CFT and Non-Relativistic String Theories  

E-Print Network (OSTI)

Cosmolog- ical uni?cation of string theories,” arXiv:hep-landscape of supercritical string theory,” arXiv:0705.0980 [invariance, supersymmetry and string theory,” Nucl. Phys.

Kim, Bom Soo

2008-01-01T23:59:59.000Z

137

Hanford Environmental Dose Reconstruction Project  

SciTech Connect

The objective of the Hanford Environmental Dose Reconstruction 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; demographics, agriculture, food habits; environmental pathways and dose estimates.

Finch, S.M.; McMakin, A.H. (comps.)

1991-01-01T23:59:59.000Z

138

Rates and Repayment Services  

NLE Websites -- All DOE Office Websites (Extended Search)

Customer Letter - Preliminary Review of Drought Adder Component for 2011 Firm Power Rates 2010 Rates and Rate Schedule - Current * 2009 Rates and Rate Schedule 2008 Rates and...

139

Standardized radiological dose evaluations  

SciTech Connect

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.

Peterson, V.L.; Stahlnecker, E.

1996-05-01T23:59:59.000Z

140

Radiochromic film based transit dosimetry for verification of dose delivery with intensity modulated radiotherapy  

Science Conference Proceedings (OSTI)

Purpose: To evaluate the transit dose based patient specific quality assurance (QA) of intensity modulated radiation therapy (IMRT) for verification of the accuracy of dose delivered to the patient. Methods: Five IMRT plans were selected and utilized to irradiate a homogeneous plastic water phantom and an inhomogeneous anthropomorphic phantom. The transit dose distribution was measured with radiochromic film and was compared with the computed dose map on the same plane using a gamma index with a 3% dose and a 3 mm distance-to-dose agreement tolerance limit. Results: While the average gamma index for comparisons of dose distributions was less than one for 98.9% of all pixels from the transit dose with the homogeneous phantom, the passing rate was reduced to 95.0% for the transit dose with the inhomogeneous phantom. Transit doses due to a 5 mm setup error may cause up to a 50% failure rate of the gamma index. Conclusions: Transit dose based IMRT QA may be superior to the traditional QA method since the former can show whether the inhomogeneity correction algorithm from TPS is accurate. In addition, transit dose based IMRT QA can be used to verify the accuracy of the dose delivered to the patient during treatment by revealing significant increases in the failure rate of the gamma index resulting from errors in patient positioning during treatment.

Chung, Kwangzoo; Lee, Kiho; Shin, Dongho; Kyung Lim, Young; Byeong Lee, Se [Proton Therapy Center, National Cancer Center, Goyang 410-769 (Korea, Republic of); Yoon, Myonggeun; Son, Jaeman [Department of Radiological Science, College of Health Science, Korea University, Seoul 136-703 (Korea, Republic of); Yong Park, Sung [Proton Therapy Center, McLaren Cancer Institute, Flint, Michigan 48532 (United States)

2013-02-15T23:59:59.000Z

Note: This page contains sample records for the topic "beta-gamma dose rates" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


141

Low Dose Radiation Program: Links - Low Dose Research in Japan...  

NLE Websites -- All DOE Office Websites (Extended Search)

Low Dose Research in Japan-Institutes and Facilities Atomic Bomb Disease Institute, Nagasaki University Institute for Environmental Sciences (IES) National Institute of...

142

Low Dose Radiation Research Program: Low Dose Radiation Research...  

NLE Websites -- All DOE Office Websites (Extended Search)

Low Dose Radiation Research: Outreach and Resources Authors: Antone L. Brooks and Lezlie A. Couch Institution: Washington State University Tri-Cities, Richland, Washington The...

143

Estimation of radiation-induced cancer from three-dimensional dose distributions: Concept of organ equivalent dose  

SciTech Connect

Purpose: Estimates of secondary cancer risk after radiotherapy are becoming more important for comparative treatment planning. Modern treatment planning systems provide accurate three-dimensional dose distributions for each individual patient. These data open up new possibilities for more precise estimates of secondary cancer incidence rates in the irradiated organs. We report a new method to estimate organ-specific radiation-induced cancer incidence rates. The concept of an organ equivalent dose (OED) for radiation-induced cancer assumes that any two dose distributions in an organ are equivalent if they cause the same radiation-induced cancer incidence. Methods and Materials: The two operational parameters of the OED concept are the organ-specific cancer incidence rate at low doses, which is taken from the data of the atomic bomb survivors, and cell sterilization at higher doses. The effect of cell sterilization in various organs was estimated by analyzing the secondary cancer incidence data of patients with Hodgkin's disease who were treated with radiotherapy in between 1962 and 1993. The radiotherapy plans used at the time the patients had been treated were reconstructed on a fully segmented whole body CT scan. The dose distributions were calculated in individual organs for which cancer incidence data were available. The model parameter that described cell sterilization was obtained by analyzing the dose and cancer incidence rates for the individual organs. Results: We found organ-specific cell radiosensitivities that varied from 0.017 for the mouth and pharynx up to 1.592 for the bladder. Using the two model parameters (organ-specific cancer incidence rate and the parameter characterizing cell sterilization), the OED concept can be applied to any three-dimensional dose distribution to analyze cancer incidence. Conclusion: We believe that the concept of OED presented in this investigation represents a first step in assessing the potential risk of secondary cancer induction after the clinical application of radiotherapy.

Schneider, Uwe [Division of Medical Physics, Department of Radiation Oncology and Nuclear Medicine, City Hospital Triemli, Zurich (Switzerland)]. E-mail: uwe.schneider@psi.ch; Zwahlen, Daniel [Division of Medical Physics, Department of Radiation Oncology and Nuclear Medicine, City Hospital Triemli, Zurich (Switzerland); Ross, Dieter [Division of Medical Physics, Department of Radiation Oncology and Nuclear Medicine, City Hospital Triemli, Zurich (Switzerland); Kaser-Hotz, Barbara [Division of Diagnostic Imaging and Radio-Oncology, Vetsuisse Faculty, University of Zuerich, Zurich (Switzerland)

2005-04-01T23:59:59.000Z

144

Low Dose Radiation Research Program: Low Dose Ionizing Radiation-Induced  

NLE Websites -- All DOE Office Websites (Extended Search)

Low Dose Ionizing Radiation-Induced Effects in Irradiated and Low Dose Ionizing Radiation-Induced Effects in Irradiated and Unirradiated cells: Pathways Analysis in Support of Risk Assessment. Authors: B.E. Lehnert, R. Cary, D. Gadbois, and G. Gupta. Institutions: Bioscience Division, Los Alamos National Laboratory. The scientific literature presents a confusing picture concerning health risks due to low dose ionizing radiation (LDIR), e.g., <1-10 cGy. Some effects of LDIR such as enhanced rates of cell proliferation and the induction of radioadaptation may be benign under some circumstances. Other evidence suggests LDIR can be hazardous and that a threshold for potentially detrimental responses, e.g., increases in intracellular reactive oxygen species (ROS), increases in sister chromatid exchanges (SCE), alterations in gene or protein expression profiles, and increased

145

Rates and Repayment Services  

NLE Websites -- All DOE Office Websites (Extended Search)

Rates Loveland Area Project Firm Power Rates Transmission and Ancillary Services Rates 2012 Rate Adjustment-Transmission and Ancillary Services 2010 Rate Adjustment-Firm Power 2009...

146

Rates and Repayment Services  

NLE Websites -- All DOE Office Websites (Extended Search)

Rates and Repayment Services Consolidated Rate Schedules FY 2014 Rates BCP Annual Rate Process Central Arizona Project Transmission Rate Process DSW Multiple System Transmission...

147

Low Dose Radiation Research Program: Genetic Factors Affecting  

NLE Websites -- All DOE Office Websites (Extended Search)

Affecting Susceptibility to Low-Dose Radiation Affecting Susceptibility to Low-Dose Radiation William F. Morgan Pacific Northwest National Laboratory Why This Project The short-term effects of high doses of ionizing radiation on cellular responses are relatively well understood. Less clear are the long-term consequences of exposure to low dose/low dose-rate radiation and the effects of radiation exposure on the progeny of surviving cells. If a cell survives radiation, it is generally thought to have repaired all the radiation-induced insults and be capable of a "normal healthy life". At a certain frequency, however, we have found that some cells surviving radiation grow normally, but will rearrange their genetic material during time in culture. We call this radiation-induced genomic instability. Many

148

Radioadaptation in Neural Stem Cells Exposed to Low Dose Irradiation  

NLE Websites -- All DOE Office Websites (Extended Search)

Radioadaptation in Neural Stem Cells Exposed to Low Dose Irradiation Radioadaptation in Neural Stem Cells Exposed to Low Dose Irradiation Charles Limoli University of California, Irvine Abstract In the CNS, irradiation of multipotent neural stem and precursor cells has been shown to cause a persistent oxidative stress that impacts radiosensitivity, mitochondrial function, and cell fate. The nature, magnitude and duration of reactive species dictates whether these radiation-induced changes are harmful or beneficial to a variety of in vitro and in vivo endpoints of viability and function. We have shown that acute low dose irradiation (2-10 cGy) can elicit significant increases in reactive oxygen (ROS) and nitrogen (RNS) species over several days post-exposure. These changes can be attenuated when the dose is protracted over several weeks using a 57Co flood source having a surface dose rate of

149

RADIOLOGICAL SURVEY OF A PORTION OF PROPERTY OWNED BY MODERN LANDFILL, INC. -  

Office of Legacy Management (LM)

A" 917 A" 917 RADIOLOGICAL SURVEY OF A PORTION OF PROPERTY OWNED BY MODERN LANDFILL, INC. - FORMER LOOW SITE Summary Report Work performed by the Health and Safety Research Division Oak Ridge National Laboratory Oak Ridge, Tennessee 37830 March 1981 OAK RIDGE NATIONAL LABORATORY operated by UNION. CARBIDE CORPORATION for the DEPARTMENT OF ENERGY as part of the Formerly Utilized Sites-- Remedial Action Program CONTENTS Page LIST OF FIGURES .. .. . .. . . . . . . . ......... iii LIST OF TABLES ......... .. iv INTRODUCTION .. ......... 1 OBJECTIVE .................... 1 SURVEY TECHNIQUES . . ............. ...... 1 RESULTS ..... 2 Gamma-Ray Exposure Rates . . . . . . 2 Beta-Gamma Dose Rate ............. 2 226Ra in Soil ............ 3 CONCLUSIONS .. . . . . . . . . . . . .. .. . .. .. 3 REFERENCES . . . . . . . . .

150

Dose Ranges Chart - May 2010  

NLE Websites -- All DOE Office Websites (Extended Search)

Charged particle event (Solar flare) dose on moon, no shielding Total Body Irradiation (TBI) Therapy Cancer Epidemiology 3 2 6 1 5 4 Natural background, USA average ...

151

ORISE: Dose modeling and assessments  

NLE Websites -- All DOE Office Websites (Extended Search)

or state regulatory compliance requirements are being met during the decontamination and decommissioning of nuclear facilities. Dose modeling is an important step in the...

152

Hanford Environmental Dose Reconstruction Project  

SciTech Connect

The objective of the Hanford Environmental Dose Reconstruction Project is to estimate the radiation doses that individuals and populations could have received from nuclear operations at Hanford since 1944. The project is being managed and conducted by the Battelle Pacific Northwest Laboratories under contract with the Centers for Disease Control. 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; environmental pathways and dose estimates.

Finch, S.M.; McMakin, A.H. (comps.)

1992-06-01T23:59:59.000Z

153

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

Science Conference Proceedings (OSTI)

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.

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

2011-05-02T23:59:59.000Z

154

Evaluation of Skyshine Dose for the Proton Accelerator Facility of the Proton Engineering Frontier Project in Korea  

Science Conference Proceedings (OSTI)

Dose/Dose Rate / Special Issue on the 11th International Conference on Radiation Shielding and the 15th Topical Meeting of the Radiation Protection and Shielding Division (Part 1) / Dosimetry

Cheol Woo Lee; Young-Ouk Lee; Young-Sik Cho

155

Low Dose Radiation Program: 2010 Low Dose Radiation Research Program  

NLE Websites -- All DOE Office Websites (Extended Search)

Low Dose Radiation Research Program Investigators' Workshop Low Dose Radiation Research Program Investigators' Workshop »» Event Slide Show More than 150 people attended this year's workshop, held April 12-14 at the Renaissance M Street Hotel in Washington, D.C. In addition to 34 plenary talks and more than 70 poster presentations made by the program investigators, participants heard guest speakers from the National Cancer Institute and from sister low-dose programs in Europe and Japan. Remarks from DOE Dr. Anna Palmisano, Associate Director, Office of Science, Director for Biological and Environmental Research (BER), welcomed the meeting participants, thanked Low Dose Radiation Research Program Manager Dr. Noelle Metting for her leadership, and acknowledged the importance of the Low Dose Program to DOE because of its unique focus and important role. She

156

What can be learned from epidemiologic studies of persons exposed to low doses of radiation?  

SciTech Connect

The main objective of radiation risk assessment is to determine the risk of various adverse health effects associated with exposure to low doses and low dose rates. Extrapolation of risks from studies of persons exposed at high doses (generally exceeding 1 Sv) and dose rates has been the primary approach used to achieve this objective. The study of Japanese atomic bomb survivors in Hiroshima and Nagasaki has played an especially important role in risk assessment efforts. A direct assessment of the dose-response function based on studies of persons exposed at low doses and dose rates is obviously desirable. This paper focuses on the potential of both current and future nuclear workers studies for investigating the dose-response functions at low doses, and also discusses analyses making use of the low dose portion of the atomic bomb survivor data. Difficulties in using these data are the statistical imprecision of estimated dose-response parameters, and potential bias resulting from confounding factors and from uncertainties in dose estimates.

Gilbert, E.S.

1993-04-01T23:59:59.000Z

157

Rates & Repayment  

NLE Websites -- All DOE Office Websites (Extended Search)

Environmental Review-NEPA Financial Data Operations Planning & Projects Power Marketing Rates Rate Adjustments Transmission Ancillary Services Rates WAPA-137 Rate Order Environmental Review-NEPA Financial Data Operations Planning & Projects Power Marketing Rates Rate Adjustments Transmission Ancillary Services Rates WAPA-137 Rate Order Rates and Repayment Services Rates Current and Historical Rate Information Collbran Power Rates CRSP Power Rates CRSP Transmission System Rates CRSP Management Center interest rates Falcon-Amistad Power Rates Provo River Power Rates Rio Grande Power Rates Seedskadee Power Rates SLCA/IP Power Rates Rate Schedules & Supplemental Rate Information Current Rates for Firm Power, Firm & Non-firm Transmission Service, & Ancillary Services Current Transmission & Ancillary Services Rates Tariffs Components of the SLCA/IP Existing Firm Power Rate Cost Recovery Charge (CRC) Page MOA Concerning the Upper Colorado River Basin

158

Radiation dose estimates for radiopharmaceuticals  

SciTech Connect

Tables of radiation dose estimates based on the Cristy-Eckerman adult male phantom are provided for a number of radiopharmaceuticals commonly used in nuclear medicine. Radiation dose estimates are listed for all major source organs, and several other organs of interest. The dose estimates were calculated using the MIRD Technique as implemented in the MIRDOSE3 computer code, developed by the Oak Ridge Institute for Science and Education, Radiation Internal Dose Information Center. In this code, residence times for source organs are used with decay data from the MIRD Radionuclide Data and Decay Schemes to produce estimates of radiation dose to organs of standardized phantoms representing individuals of different ages. The adult male phantom of the Cristy-Eckerman phantom series is different from the MIRD 5, or Reference Man phantom in several aspects, the most important of which is the difference in the masses and absorbed fractions for the active (red) marrow. The absorbed fractions for flow energy photons striking the marrow are also different. Other minor differences exist, but are not likely to significantly affect dose estimates calculated with the two phantoms. Assumptions which support each of the dose estimates appears at the bottom of the table of estimates for a given radiopharmaceutical. In most cases, the model kinetics or organ residence times are explicitly given. The results presented here can easily be extended to include other radiopharmaceuticals or phantoms.

Stabin, M.G.; Stubbs, J.B.; Toohey, R.E. [Oak Ridge Inst. of Science and Education, TN (United States). Radiation Internal Dose Information Center

1996-04-01T23:59:59.000Z

159

Hanford Environmental Dose Reconstruction Project  

Science Conference Proceedings (OSTI)

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.

McMakin, A.H.; Cannon, S.D.; Finch, S.M. (comps.)

1992-07-01T23:59:59.000Z

160

Radiation Leukaemogenesis at Low Doses  

NLE Websites -- All DOE Office Websites (Extended Search)

myeloid leukaemia development at high and low doses. References 1. Cook WD, McCaw BJ, Herring C, John DL, Foote SJ, Nutt SL and Adams JM (2004). PU.1 is a suppressor of myeloid...

Note: This page contains sample records for the topic "beta-gamma dose rates" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


161

Low doses of neutrons induce changes in gene expression  

SciTech Connect

Studies were designed to identify genes induced following low-dose neutron but not following {gamma}-ray exposure in fibroblasts. Our past work had shown differences in the expression of {beta}-protein kinase C and c-fos genes, both being induced following {gamma}-ray but not neutron exposure. We have identified two genes that are induced following neutron, but not {gamma}-ray, exposure: Rp-8 (a gene induced by apoptosis) and the long terminal repeat (LTR) of the human immunodeficiency (HIV). Rp-8 mRNA induction was demonstrated in Syrian hamster embryo fibroblasts and was found to be induced in cells exposed to neutrons administered at low (0.5 cGy/min) and at high dose rate (12 cGy/min). The induction of transcription from the LTR of HIV was demonstrated in HeLa cells bearing a transfected construct of the chloramphenicol acetyl transferase (CAT) gene driven by the HIV-LTR promoter. Measures of CAT activity and CAT transcripts following irradiation demonstrated an unresponsiveness to {gamma} rays over a broad range of doses. Twofold induction of the HIV-LTR was detected following neutron exposure (48 cGy) administered at low (0.5 cGy/min) but not high (12 cGy/min) dose rates. Ultraviolet-mediated HIV-LTR induction was inhibited by low-dose-rate neutron exposure.

Woloschak, G.E.; Chang-Liu, C.M. [Argonne National Lab., IL (United States); Panozzo, J.; Libertin, C.R. [Loyola Univ., Maywood, IL (United States)

1993-06-01T23:59:59.000Z

162

Low doses of neutrons induce changes in gene expression  

SciTech Connect

Studies were designed to identify genes induced following low-dose neutron but not following [gamma]-ray exposure in fibroblasts. Our past work had shown differences in the expression of [beta]-protein kinase C and c-fos genes, both being induced following [gamma]-ray but not neutron exposure. We have identified two genes that are induced following neutron, but not [gamma]-ray, exposure: Rp-8 (a gene induced by apoptosis) and the long terminal repeat (LTR) of the human immunodeficiency (HIV). Rp-8 mRNA induction was demonstrated in Syrian hamster embryo fibroblasts and was found to be induced in cells exposed to neutrons administered at low (0.5 cGy/min) and at high dose rate (12 cGy/min). The induction of transcription from the LTR of HIV was demonstrated in HeLa cells bearing a transfected construct of the chloramphenicol acetyl transferase (CAT) gene driven by the HIV-LTR promoter. Measures of CAT activity and CAT transcripts following irradiation demonstrated an unresponsiveness to [gamma] rays over a broad range of doses. Twofold induction of the HIV-LTR was detected following neutron exposure (48 cGy) administered at low (0.5 cGy/min) but not high (12 cGy/min) dose rates. Ultraviolet-mediated HIV-LTR induction was inhibited by low-dose-rate neutron exposure.

Woloschak, G.E.; Chang-Liu, C.M. (Argonne National Lab., IL (United States)); Panozzo, J.; Libertin, C.R. (Loyola Univ., Maywood, IL (United States))

1993-01-01T23:59:59.000Z

163

PROTRACTED LOW DOSE PHOTON AND SIMULATED SOLAR FLARE  

NLE Websites -- All DOE Office Websites (Extended Search)

PROTRACTED LOW DOSE PHOTON AND SIMULATED SOLAR FLARE PROTRACTED LOW DOSE PHOTON AND SIMULATED SOLAR FLARE PROTON EFFECTS ON CYTOKINE/CHEMOKINE EXPRESSION AFTER WHOLE-BODY IRRADIATION Asma Rizvi 2 , George Coutrakon 1 , James M. Slater 1 , Michael J. Pecaut 1,2 and Daila S. Gridley 1,2 Departments. of 1 Radiation Medicine and 2 Biochemistry & Microbiology Loma Linda University & Medical Center, Loma Linda, CA 92354 Astronauts are exposed to low dose/low dose rate radiation (LDR) and may also be acutely irradiated during a solar particle event (SPE). The biological effects of LDR alone and when combined with a solar particle event, are not yet clearly understood. Previous studies have shown that irradiation can have adverse effects on T cells. The reactive oxygen species (ROS) that are produced as a result of radiation can alter or damage the

164

Low Dose Radiation Research Program: Slide Shows  

NLE Websites -- All DOE Office Websites (Extended Search)

Dose Health Effects of Radiation Health Effects of Radiation Adaptive Response to Low Dose Radiation PDF Background Radiation PDF Bystander Effects PDF Dirty Bombs PDF DNA Damage...

165

The Use of Collective Dose for Optimization of a Low-Level Waste Site Closure Cover  

Science Conference Proceedings (OSTI)

Low-level radioactive waste management regulations require that releases to the environment be as low as reasonably achievable. Collective dose’s use in quantitative cost benefit analysis is well accepted for optimization of operational radiation safety, but seldom applied to routine environmental releases. One concern is that collective dose for large areas and long time periods may obscure the spatial and temporal distribution of risk and the magnitude of individual doses. Use of collective dose for optimization also requires that the decision maker justify subjective inputs including truncation limits for the summation of collective dose in space and time, a monetary value for collective dose, and a discount rate for future health detriment. In this study, a probabilistic collective dose model is developed and used to optimize the closure of the Area 5 Radioactive Waste Management Site (RWMS) on the Nevada Test Site. Collective dose’s shortcomings are addressed by preparing a dose matrix that disaggregates the collective dose in space and time and by reporting individual doses for exposed subgroups. Important subjective inputs are assigned discrete values reflecting differing opinions, and the consequence of the differences on the final decision is described. The resulting optimization process remains subjective, but clearly identifies subjective inputs, the values selected, and their impact on the decision. For the Area 5 RWMS, the value of the collective dose is small compared to closure cover cost options over a broad range of subjective values for the spatial and temporal limits for truncation of collective dose, monetary value of collective dose, and discount rates for future dose. The collective dose matrix and individual doses indicate that the societal and individual risks are greatest for future residents within the disposal site boundary, suggesting that options deterring intrusion have the greatest potential for cost-effectiveness. The cost of various closure options far exceeds the value of the collective dose averted, indicating that there are few opportunities for cost-effective improvements when closures meet the low dose constraints in waste management regulations.

Greg Shott, Vefa Yucel

2010-03-07T23:59:59.000Z

166

Data Center Rating Infrastructure Rating Development  

NLE Websites -- All DOE Office Websites (Extended Search)

in Portfolio Manager on June 7, 2010. The questions below are designed to help data center owners and operators better understand the rating and benchmark their buildings in...

167

Radiation Leukaemongenesis at Low Doses  

NLE Websites -- All DOE Office Websites (Extended Search)

Leukaemongenesis at Low Doses Leukaemongenesis at Low Doses Simon Bouffler Health Protection Agency Abstract Myeloid leukaemias feature prominently among the cancers associated with human exposures to ionising radiation. The CBA mouse model of radiation-induced acute myeloid leukaemia (AML) has been used extensively for both quantitative and mechanistic studies. Loss of genetic material from chromosome 2 (chr2) is known to be associated with most radiation-induced AMLs. AML develops in CBA mice exposed to X- or γ-radiation, after a mean latency period of 18 months, with a maximal incidence of approximately 25% at 3Gy. A strong candidate AML-suppressor gene located within the commonly deleted region of chr2 has been identified, Sƒpil/PU.1. This gene suffers hemizygous loss and specific

168

Radiation dose from cigarette tobacco  

SciTech Connect

The radioactivity in tobacco leaves collected from 15 different regions of Greece before cigarette production was studied in order to estimate the effective dose from cigarette tobacco due to the naturally occurring primordial radionuclides, such as {sup 226}Ra and {sup 210}Pb of the uranium series and {sup 228}Ra of the thorium series and/or man-made produced radionuclides, such as {sup 137}Cs of Chernobyl origin. Gamma-ray spectrometry was applied using Ge planar and coaxial type detectors of high resolution and high efficiency. It was concluded that the annual effective dose due to inhalation for adults (smokers) for {sup 226}Ra varied from 42.5 to 178.6 {mu}Sv y{sup -1} (average 79.7 {mu}Sv y{sup -1}), while for {sup 228}Ra from 19.3 to 116.0 {mu}Sv y{sup -1} (average 67.1 {mu}Sv y{sup -1}) and for {sup 210}Pb from 47.0 to 134.9 {mu}Sv y{sup -1} (average 104.7 {mu}Sv y{sup -1}), that is the same order of magnitude for each radionuclide. The sum of the effective dose of the three natural radionuclides varied from 151.9 to 401.3 {mu}Sv y{sup -1} (average 251.5 {mu}Sv y{sup -1}). The annual effective dose from {sup 137}Cs of Chernobyl origin was three orders of magnitude lower as it varied from 70.4 to 410.4 nSv y{sup -1} (average 199.3 nSv y{sup -1})

Papastefanou, C. [Aristotle University of Thessaloniki, Atomic and Nuclear Physics Laboratory, Thessaloniki 54124 (Greece)

2008-08-07T23:59:59.000Z

169

Tracking the Libor Rate  

E-Print Network (OSTI)

Investigating the Libor Rate,” mimeo. Abrantes-Metz, R. ,Libor data: Historial 1 month Libor rates, British Bankers1108R) Tracking the Libor Rate Rosa M. Abrantes-Metz , Sofia

Abrantes-Metz, Rosa; Villas-Boas, Sofia B.; Judge, George G.

2013-01-01T23:59:59.000Z

170

Rail Coal Transportation Rates  

U.S. Energy Information Administration (EIA)

figure data Figure 7 shows the percent change in average real rates for those state-to-state ... Estimated transportation rates for coal delivered to electric ...

171

2012 Rate Adjustments  

NLE Websites -- All DOE Office Websites (Extended Search)

Register Notices Meetings Brochure Brochure Addendum Customer Comment Letter Approved Rate Order FERC Confirmation If you have questions, call Rates and Repayment, 800-472-2306...

172

Effective Rate Period  

NLE Websites -- All DOE Office Websites (Extended Search)

10012012 - 09302013 Mid-Year Changes (if applicable) 10012012 - 09302013 Power Rates Annual Revenue Requirement Rate Schedule Power Revenue Requirement 73,381,487...

173

Low doses of neutrons induce changes in gene expression  

SciTech Connect

Studies were designed to identify genes induced in fibroblasts after exposure to low-dose neutron radiation but not after {gamma} rays. Our past work had shown similar modulation of transcripts for {alpha}-tubulin, {beta}- and {gamma}-actins, ornithine decarboxylase and interleukin 1 after exposure to either neutrons or {gamma} rays. However, differences in the expression of {beta}-protein kinase C and c-fos genes were observed, with both being induced after exposure to {gamma} rays but not neutrons. Recently, we have identified two genes that are induced after exposure to neutrons but not {gamma} rays: Rp-8 (a gene associated with apoptosis) and the long terminal repeat (LTR) of the human immunodeficiency virus (HIV). Induction of Rp-8 mRNA was demonstrated in Syrian hamster embryo (SHE) fibroblasts and was found to be induced in cells exposed to neutrons administered at low (0.005 Gy/min) and high dose rate (0.12 Gy/min). No induction of other genes associated with apoptosis such as Rp-2, bcl-2 and Tcl-30 was observed. The induction of transcription from the LTR of HIV was demonstrated in HeLa cells bearing a transfected construct of the chloramphenicol acetyl transferase (CAT) gene driven by the HIV-LTR promoter. Measurements of CAT activity and CAT transcripts after irradiation demonstrated an unresponsiveness to {gamma} rays over a broad range of doses (0.1-3 Gy). Twofold induction of the HIV-LTR was detected after exposure to neutrons (0.48 Gy) administered at low (0.05 Gy/min) but not high (0.12 Gy/min) dose rates. Ultraviolet-mediated HIV-LTR induction, however, was inhibited by exposure to low-dose-rate neutron irradiation. These results are interesting in light of reports that Rp-8 is induced during apoptosis and that HIV causes apoptosis. 17 refs., 3 figs., 1 tab.

Woloschak, G.E.; Chang-Liu, C.M. [Argonne National Lab., IL (United States); Panozzo, J.; Libertin, C.R. [Loyola Univ. of Chicago, Maywood, IL (United States)

1994-04-01T23:59:59.000Z

174

Low Dose Radiation Research Program: Image Gallery  

NLE Websites -- All DOE Office Websites (Extended Search)

Image Gallery Image Gallery These are images, photographs, and charts presented or developed for Low Dose Radiation Research Investigators’ Meetings. They may be used for presentations or reports. To save, right click on the picture, then choose "Save picture as." U.S. annual per-capita effective radiation dose from various sources for 1980. various sources 1980 Enlarge Image. U.S. annual per-capita effective radiation dose from various sources for 2006. various sources 2006 Enlarge Image. U.S. annual per-capita effective radiation dose from man-made sources in the United States for 2006. man-made 2006 Enlarge Image. Ionizing Radiation Dose Ranges showing the wide range of radiation doses that humans experience (Rem) Enlarge Image. Ionizing Radiation Dose Ranges showing the wide range of radiation doses that humans experience

175

Measurements of cosmic radiation dose in subsonic commercial aircraft compared to the city-pair dose calculation  

SciTech Connect

The radiation dose received by passengers during flight on conventional jet aircraft was determined as a function of exposure to cosmic radiation, solar radiation, flight time, and flight path. The dosimetric measurements were made with thermoluminescent dosimeters (TLD's) and with emulsions of three types sealed in plastic packets. These packets were sent by air mail back and forth from Berkeley, California to five cities and a dose sufficiently above background for a satisfactory measurement was accumulated by the TLD's on one round trip and by the emulsions on three round trips. It was concluded that both experiments and theory show that the total doses received at present day conventional jet aircraft altitudes are considerably higher than those encountered in supersonic flights at much higher altitudes, even though the dose rate is lower at these lower altitudes, when the longer time of exposure at the lower altitudes is taken into consideration. Computer programs used in the dose calculations are included. (CH)

Wallace, R.

1973-07-16T23:59:59.000Z

176

Hanford Environmental Dose Reconstruction Project. Monthly report  

Science Conference Proceedings (OSTI)

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.

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

1992-10-01T23:59:59.000Z

177

Hanford Environmental Dose Reconstruction Project. Monthly report  

SciTech Connect

The objective of the Hanford Environmental Dose Reconstruction 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.

Finch, S.M.; McMakin, A.H. [comps.

1992-04-01T23:59:59.000Z

178

rates | OpenEI  

Open Energy Info (EERE)

rates rates Dataset Summary Description This dataset, compiled by NREL and Ventyx, provides average residential, commercial and industrial electricity rates by zip code for both investor owned utilities (IOU) and non-investor owned utilities. Note: the file includes average rates for each utility, but not the detailed rate structure data found in the database available via the zip-code look-up feature on the OpenEI Utilities page (http://en.openei.org/wiki/Gateway:Utilities). The data was released by NREL/Ventyx in February 2011. Source NREL and Ventyx Date Released February 24th, 2012 (2 years ago) Date Updated Unknown Keywords electric rates rates US utilities Data text/csv icon IOU rates by zipcode (csv, 1.7 MiB) text/csv icon Non-IOU rates by zipcode (csv, 2.1 MiB)

179

Historical Interest Rates  

NLE Websites -- All DOE Office Websites (Extended Search)

Current and Historical Interest Rates Current and Historical Interest Rates The table lists interest rates, from the project's inception through the present, for all projects with repayment supervised by the CRSP MC. The latest available interest rate is used for all future interest rate calculations. The Amistad-Falcon, Collbran, Provo River, and Rio Grande Projects are all assigned the average daily "Yield Rate" calculated by the U.S. Treasury, on an annual basis, for Treasury bonds having terms of 15 years or more remaining to maturity. The calculated yield rate is rounded to the nearest one-eighth of one percent. The yield rate is based upon the bond's interest rate, as well as its market value. The Colorado River Storage Project and its participating projects, Dolores and Seedskadee, are assigned the average daily "Coupon Rate," annualized for the same U.S. Treasury bonds used in "Yield Rate" calculations. The coupon rate is the interest rate that the bond carries upon its face.

180

Tracking the Libor Rate  

E-Print Network (OSTI)

Paper 1108R2 Paper 1108R) Tracking the Libor Rate Rosa M.revision 2013 by author(s). Tracking the Libor Rate Rosa M.providing a methodology for tracking the dynamic integrity

Abrantes-Metz, Rosa; Villas-Boas, Sofia B.; Judge, George G.

2013-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "beta-gamma dose rates" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


181

2009 Rate Adjustments  

NLE Websites -- All DOE Office Websites (Extended Search)

provisional rates will be in effect until the Federal Energy Regulatory Commission (FERC) confirms and approves them on a final basis or until they are replaced by other rates....

182

Mouse heart rate  

NLE Websites -- All DOE Office Websites (Extended Search)

Mouse heart rate Name: amj Status: NA Age: NA Location: NA Country: NA Date: Around 1993 Question: Is it possible to get the heart rate of a mouse without special equipment?...

183

Dynamics of heart rate  

Science Conference Proceedings (OSTI)

Heart rate oscillates on several different time scales and has long?term variability in the form of 1/fnoise. The physiological control of heart rate is briefly reviewed

Daniel T. Kaplan; Mario Talajic

1991-01-01T23:59:59.000Z

184

Dose assessment for radioactive contamination of a child  

E-Print Network (OSTI)

Dose assessments produced using the computer code MCNP are important to simulate events that are difficult to recreate experimentally. An emergency scenario involving whole-body skin contamination is one example of such an event. For these scenarios, an anthropomorphic phantom of a 10-year-old male with uniform skin contamination was created and combined with MCNP for dose calculations. Activity on the skin was modeled with gamma-ray sources at energies of 50 keV, 100 keV, 250 keV, 500 keV, 750 keV, 1 MeV, 1.25 MeV, 1.5 MeV, and 2 MeV. The radionuclides 60Co, 137Cs, and 131I were also modeled. The effective dose to the body and major organs was calculated for each scenario. Exposure rate contour lines were also produced around the body. The activity required to result in a dose equal to the legal limit of 0.1 mSv for minors was calculated for each scenario. The highest activity required to produce this limit was from the 50 keV gamma-ray source. This activity was increased by an arbitrary value, approximately tenfold the current value, to represent an emergency scenario. This new activity concentration of 1 mCi per 100 cm2 was used to produce doses for each of the scenarios. The lowest effective dose for the body was 0.82 mSv, produced from the 50 keV source. The highest effective dose was 19.59 mSv, produced from the 2 MeV source. The exposure rates nearest the body were approximately 1.25 R/h, decreasing to100 mR/h approximately 60 cm from the body. The data points were found to be dependent on the energy of the gamma ray. These data can also be improved by deriving solutions previously assumed in this scenario. For example, the skin may be broken down into multiple regions to allow for independent calculations for regional contamination. The activity on the skin can also be derived from air concentration models, allowing for the use of other models to be used in conjunction with this research.

Kowalczik, Jeffrey Aaron

2008-05-01T23:59:59.000Z

185

INDOS: conversational computer codes to implement ICRP-10-10A models for estimation of internal radiation dose to man  

SciTech Connect

INDOS1, INDOS2, and INDOS3 (the INDOS codes) are conversational FORTRAN IV programs, implemented for use in time-sharing mode on the ORNL PDP-10 System. These codes use ICRP10-10A models to estimate the radiation dose to an organ of the body of Reference Man resulting from the ingestion or inhalation of any one of various radionuclides. Two patterns of intake are simulated: intakes at discrete times and continuous intake at a constant rate. The IND0S codes provide tabular output of dose rate and dose vs time, graphical output of dose vs time, and punched-card output of organ burden and dose vs time. The models of internal dose calculation are discussed and instructions for the use of the INDOS codes are provided. The INDOS codes are available from the Radiation Shielding Information Center, Oak Ridge National Laboratory, P. O. Box X, Oak Ridge, Tennessee 37830. (auth)

Killough, G.G.; Rohwer, P.S.

1974-03-01T23:59:59.000Z

186

Simulation of dose reduction in tomosynthesis  

Science Conference Proceedings (OSTI)

Purpose: Methods for simulating dose reduction are valuable tools in the work of optimizing radiographic examinations. Using such methods, clinical images can be simulated to have been collected at other, lower, dose levels without the need of additional patient exposure. A recent technology introduced to healthcare that needs optimization is tomosynthesis, where a number of low-dose projection images collected at different angles is used to reconstruct section images of an imaged object. The aim of the present work was to develop a method of simulating dose reduction for digital radiographic systems, suitable for tomosynthesis. Methods: The developed method uses information about the noise power spectrum (NPS) at the original dose level and the simulated dose level to create a noise image that is added to the original image to produce an image that has the same noise properties as an image actually collected at the simulated dose level. As the detective quantum efficiency (DQE) of digital detectors operating at the low dose levels used for tomosynthesis may show a strong dependency on the dose level, it is important that a method for simulating dose reduction for tomosynthesis takes this dependency into account. By applying an experimentally determined relationship between pixel mean and pixel variance, variations in both dose and DQE in relevant dose ranges are taken into account. Results: The developed method was tested on a chest tomosynthesis system and was shown to produce NPS of simulated dose-reduced projection images that agreed well with the NPS of images actually collected at the simulated dose level. The simulated dose reduction method was also applied to tomosynthesis examinations of an anthropomorphic chest phantom, and the obtained noise in the reconstructed section images was very similar to that of an examination actually performed at the simulated dose level. Conclusions: In conclusion, the present article describes a method for simulating dose reduction suitable for tomosynthesis. However, the method applies equally well to any digital radiographic system, although the benefits of correcting for DQE variations may be smaller.

Svalkvist, Angelica; Baath, Magnus [Department of Radiation Physics, University of Gothenburg, SE-413 45 Gothenburg (Sweden) and Department of Medical Physics and Biomedical Engineering, Sahlgrenska University Hospital, SE-413 45 Gothenburg (Sweden)

2010-01-15T23:59:59.000Z

187

Toward IMRT 2D dose modeling using artificial neural networks: A feasibility study  

Science Conference Proceedings (OSTI)

Purpose: To investigate the feasibility of artificial neural networks (ANN) to reconstruct dose maps for intensity modulated radiation treatment (IMRT) fields compared with those of the treatment planning system (TPS). Methods: An artificial feed forward neural network and the back-propagation learning algorithm have been used to replicate dose calculations of IMRT fields obtained from PINNACLE{sup 3} v9.0. The ANN was trained with fluence and dose maps of IMRT fields for 6 MV x-rays, which were obtained from the amorphous silicon (a-Si) electronic portal imaging device of Novalis TX. Those fluence distributions were imported to the TPS and the dose maps were calculated on the horizontal midpoint plane of a water equivalent homogeneous cylindrical virtual phantom. Each exported 2D dose distribution from the TPS was classified into two clusters of high and low dose regions, respectively, based on the K-means algorithm and the Euclidian metric in the fluence-dose domain. The data of each cluster were divided into two sets for the training and validation phase of the ANN, respectively. After the completion of the ANN training phase, 2D dose maps were reconstructed by the ANN and isodose distributions were created. The dose maps reconstructed by ANN were evaluated and compared with the TPS, where the mean absolute deviation of the dose and the {gamma}-index were used. Results: A good agreement between the doses calculated from the TPS and the trained ANN was achieved. In particular, an average relative dosimetric difference of 4.6% and an average {gamma}-index passing rate of 93% were obtained for low dose regions, and a dosimetric difference of 2.3% and an average {gamma}-index passing rate of 97% for high dose region. Conclusions: An artificial neural network has been developed to convert fluence maps to corresponding dose maps. The feasibility and potential of an artificial neural network to replicate complex convolution kernels in the TPS for IMRT dose calculations have been demonstrated.

Kalantzis, Georgios; Vasquez-Quino, Luis A.; Zalman, Travis; Pratx, Guillem; Lei, Yu [Radiation Oncology Department, University of Texas, Health Science Center San Antonio, Texas 78229 and Radiation Oncology Department, Stanford University School of Medicine, Stanford, California 94305 (United States); Radiation Oncology Department, University of Texas, Health Science Center San Antonio, Texas 78229 (United States); Radiation Oncology Department, Stanford University School of Medicine, Stanford, California 94305 (United States); Radiation Oncology Department, University of Texas, Health Science Center San Antonio, Texas 78229 (United States)

2011-10-15T23:59:59.000Z

188

Dose estimates of alternative plutonium pyrochemical processes.  

Science Conference Proceedings (OSTI)

We have coupled our dose calculation tool Pandemonium with a discrete-event, object-oriented, process-modeling system ProMosO to analyze a set of alternatives for plutonium purification operations. The results follow expected trends and indicate, from a dose perspective, that an experimental flowsheet may warrant further research to see if it can be scaled to industrial levels. Flowsheets that include fluoride processes resulted in the largest doses.

Kornreich, D. E. (Drew E.); Jackson, J. W. (Joseph W.); Boerigter, S. T. (Stephen T.); Averill, W. A. (William A.); Fasel, J. H. (Joseph H.)

2002-01-01T23:59:59.000Z

189

Low dose diagnostic radiation exposure and cancer risk in Trp53+/- mice  

NLE Websites -- All DOE Office Websites (Extended Search)

diagnostic radiation exposure and cancer risk in Trp53+/- mice diagnostic radiation exposure and cancer risk in Trp53+/- mice K Taylor, N Phan, ME Cybulski, L Laframboise, DR Boreham Department of Medical Physics and Applied Radiation Sciences, McMaster University, 1280 Main Street West, Hamilton ON L8S 4K1 The cancer risk associated with exposure to low doses of ionizing radiation has traditionally been extrapolated from effects observed at high doses and high dose rates using a linear no threshold model. Based on this approach, it has been postulated that human exposure to medical imaging involving low doses of x-rays and gamma rays increase an individual's risk of developing cancer throughout their lifetime. Conversely, there is evidence that low doses of gamma radiation increase the latency period of cancer depending upon genotype, cancer type, and the magnitude of

190

Plastic packaging and burn-in effects on ionizing dose response in CMOS microcircuits  

Science Conference Proceedings (OSTI)

Results are reported from an investigation of the effects of packaging and burn-in on the post-irradiation performance of National Semiconductor 54AC02 Quad 2-input NOR gates. The test population was drawn from a single wafer fabricated in the National process qualified under Mil-Prf-38535 to an ionizing radiation hardness of 100 krads(Si). The test sample was divided between plastic and ceramic packages. Additionally, half of the plastic samples and half of the two ceramic samples received a 168 hour/125 C burn-in. Two irradiation schemes were used. The first followed Mil-Std-883 Method 1019.4 (dose rate = 50 rads(Si)/s). The second used a low dose rate (0.1 rads(Si)/s). AC, DC, transfer function and functional behavior were monitored throughout the tests. Significant differences among the package types and burn-in variations were noted with the plastic, burned-in components demonstrating enhanced degradation. They show the worst post-irradiation parameter values as well as very broad post-irradiation parameter distributions. Degradation is highly dependent upon dose rate and anneal conditions. Two different radiation induced leakage paths have been identified, and their characteristics have been correlated to variations in high dose rate and low dose rate circuit performance. Caution is recommended for system developers to ensure that radiation hardness characterization is performed for the same package/burn-in configuration to be used in the system.

Clark, S.D.; Bings, J.P. [Naval Surface Warfare Center, Crane, IN (United States). Crane Div.; Maher, M.C.; Williams, M.K.; Alexander, D.R.; Pease, R.L.

1995-12-01T23:59:59.000Z

191

Low Dose Radiation Research Program: Research Highlights  

NLE Websites -- All DOE Office Websites (Extended Search)

energy, are the surrounding unirradiated cells also at an increased risk of cancer? Latest Research, Response to Fukushima, Integrating Low Dose into Policy-All Featured at...

192

Low Dose Radiation Research Program: Transgenerational Effects...  

NLE Websites -- All DOE Office Websites (Extended Search)

Transgenerational Effects of Chronic Low-Dose Irradiation in a Medaka Fish Model System Colorado State University Why this Project? There are major gaps in our knowledge about...

193

Low Dose Radiation Program: Selected Websites  

NLE Websites -- All DOE Office Websites (Extended Search)

The views expressed in these links do not necessarily reflect the view of the Low Dose Radiation Research Program. Scientific Links Agencies with Radiation Regulatory...

194

Low Dose Radiation Research Program: Katherine Vallis  

NLE Websites -- All DOE Office Websites (Extended Search)

Margaret Hospital Newly Funded Project The Characterization of Genetic Responses to Low Dose Radiation Using a Genome-Wide Insertional Mutagensis Approach Technical Abstracts 2005...

195

'Slow-Blooming Phases' in High Dose  

Science Conference Proceedings (OSTI)

Ab Initio Study of Radiation-Induced Amorphization Mechanisms in SiC and ZrC ... and Irradiation Hardening of Zircaloy during Low Dose Neutron Irradiation at ...

196

Low Dose Radiation Research Program: Mohan Natarajan  

NLE Websites -- All DOE Office Websites (Extended Search)

of Survival Advantage, Bystander Effect, and Genomic Instability after Low-LET Low Dose Radiation Exposure Funded Project Real-Time Molecular Study of Bystander Effect Using...

197

Low Dose Radiation Research Program: Multidimensional Analysis...  

NLE Websites -- All DOE Office Websites (Extended Search)

Multidimensional Analysis of Human Epithelial Cell Response to Low Dose Radiation Mary Helen Barcellos-Hoff Lawrence Berkeley National Laboratory Berkeley, CA. (Jointly funded by...

198

ORISE: Radiation Dose Estimates and Other Compendia  

NLE Websites -- All DOE Office Websites (Extended Search)

article addresses methods that can be used to rapidly estimate internal and external radiation dose magnitudes that can be used to help guide early medical management. Included...

199

About the Ratings  

NLE Websites -- All DOE Office Websites (Extended Search)

2008 Ratings Changes 2008 Ratings Changes EPA's "New" Fuel Economy Ratings Video about EPA's New Fuel Economy Ratings Windows Media Video (6.8 MB) Quicktime Video (7.8 MB) Text Version EPA changed the way it estimates fuel economy starting with the 2008 model year. This "new" way of estimating fuel economy supplements the previous method by incorporating the effects of Faster speeds and acceleration Air conditioner use Colder outside temperatures What else do I need to know about the "new" ratings? The tests lower MPG estimates for most vehicles. View old/new MPG ratings for a specific vehicle The actual mileage you get will still vary based on your driving habits, traffic conditions, and other factors. All MPG estimates in Find-a-Car have been converted to the new

200

Effective Rate Period  

NLE Websites -- All DOE Office Websites (Extended Search)

Fiscal Year 2014 Fiscal Year 2014 Effective Rate Period As of Beginning of the FY 10/01/2013 - 09/30/2014 Mid-Year Changes (if applicable) 10/01/2013 - 09/30/2014 Power Rates Annual Revenue Requirement Rate Schedule Power Revenue Requirement $73,441,557 CV-F13 Base Resource Revenue Requirement $69,585,875 First Preference Revenue Requirement $3,855,682

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201

High Redshift Supernova Rates  

E-Print Network (OSTI)

We use a sample of 42 supernovae detected with the Advanced Camera for Surveys on-board the Hubble Space Telescope as part of the Great Observatories Origins Deep Survey to measure the rate of core collapse supernovae to z~0.7 and type Ia supernovae to z~1.6. This significantly increases the redshift range where supernova rates have been estimated from observations. The rate of core collapse supernovae can be used as an independent probe of the cosmic star formation rate. Based on the observations of 17 core collapse supernovae, we measure an increase in the core collapse supernova rate by a factor of 1.6 in the range 0.3rate. The increase in the rate in this redshift range in consistent with recent measurements of the star formation rate derived from UV-luminosity densities and IR datasets. Based on 25 type Ia supernovae, we find a SN Ia rate that is a factor 3-5 higher at z~1 compared to earlier estimates at lower redshifts (zrate traces a higher star formation rate at redshifts z>1 compared to low redshift. At higher redshift (z>1), we find a suggested decrease in the type Ia rate with redshift. This evolution of the Ia rate with redshift is consistent with a type Ia progenitor model where there is a substantial delay between the formation of the progenitor star and the explosion of the supernova. Assuming that the type Ia progenitor stars have initial main sequence masses 3-8 M_Sun, we find that 5-7% of the available progenitors explode as type Ia supernovae.

Tomas Dahlen; Louis-Gregory Strolger; Adam G. Riess; Bahram Mobasher; Ranga-Ram Chary; Christopher J. Conselice; Henry C. Ferguson; Andrew S. Fruchter; Mauro Giavalisco; Mario Livio; Piero Madau; Nino Panagia; John L. Tonry

2004-06-24T23:59:59.000Z

202

VMAT QA: Measurement-guided 4D dose reconstruction on a patient  

Science Conference Proceedings (OSTI)

Purpose: To develop and validate a volume-modulated arc therapy (VMAT) quality assurance (QA) tool that takes as input a time-resolved, low-density ({approx}10 mm) cylindrical surface dose map from a commercial helical diode array, and outputs a high density, volumetric, time-resolved dose matrix on an arbitrary patient dataset. This first validation study is limited to a homogeneous 'patient.'Methods: A VMAT treatment is delivered to a diode array phantom (ARCCHECK, Sun Nuclear Corp., Melbourne, FL). 3DVH software (Sun Nuclear) derives the high-density volumetric dose using measurement-guided dose reconstruction (MGDR). MGDR cylindrical phantom results are then used to perturb the three-dimensional (3D) treatment planning dose on the patient dataset, producing a semiempirical volumetric dose grid. Four-dimensional (4D) dose reconstruction on the patient is also possible by morphing individual sub-beam doses instead of the composite. For conventional (3D) dose comparison two methods were developed, using the four plans (Multi-Target, C-shape, Mock Prostate, and Head and Neck), including their structures and objectives, from the AAPM TG-119 report. First, 3DVH and treatment planning system (TPS) cumulative point doses were compared to ion chamber in a cube water-equivalent phantom ('patient'). The shape of the phantom is different from the ARCCHECK and furthermore the targets were placed asymmetrically. Second, coronal and sagittal absolute film dose distributions in the cube were compared with 3DVH and TPS. For time-resolved (4D) comparisons, three tests were performed. First, volumetric dose differences were calculated between the 3D MGDR and cumulative time-resolved patient (4D MGDR) dose at the end of delivery, where they ideally should be identical. Second, time-resolved (10 Hz sampling rate) ion chamber doses were compared to cumulative point dose vs time curves from 4D MGDR. Finally, accelerator output was varied to assess the linearity of the 4D MGDR with global fluence change. Results: Across four TG-119 plans, the average PTV point dose difference in the cube between 3DVH and ion chamber is 0.1 {+-} 1.0%. Average film vs TPS {gamma}-analysis passing rates are 83.0%, 91.1%, and 98.4% for 1%/2 mm, 2%/2 mm, and 3%/3 mm threshold combinations, respectively, while average film vs 3DVH {gamma}-analysis passing rates are 88.6%, 96.1%, and 99.5% for the same respective criteria. 4D MGDR was also sufficiently accurate. First, for 99.5% voxels in each case, the doses from 3D and 4D MGDR at the end of delivery agree within 0.5%local dose-error/1 mm distance. Moreover, all failing voxels are confined to the edge of the cylindrical reconstruction volume. Second, dose vs time curves track between the ion chamber and 4D MGDR within 1%. Finally, 4D MGDR dose changes linearly with the accelerator output: the difference between cumulative ion chamber and MGDR dose changed by no more than 1% (randomly) with the output variation range of 10%. Conclusions: Even for a well-commissioned TPS, comparison metrics show better agreement on average to MGDR than to TPS on the arbitrary-shaped measurable 'patient.' The method requires no more accelerator time than standard QA, while producing more clinically relevant information. Validation in a heterogeneous thoracic phantom is under way, as is the ultimate application of 4D MGDR to virtual motion studies.

Nelms, Benjamin E.; Opp, Daniel; Robinson, Joshua; Wolf, Theresa K.; Zhang, Geoffrey; Moros, Eduardo; Feygelman, Vladimir [Canis Lupus LLC, Merrimac, Wisconsin 53561 (United States); Department of Radiation Oncology, Moffitt Cancer Center, Tampa, Florida 33612 (United States); Department of Physics, University of South Florida, Tampa, Florida 33612 (United States); Live Oak Technologies LLC, Kirkwood, Missouri 63122 (United States); Department of Radiation Oncology, Moffitt Cancer Center, Tampa, Florida 33612 (United States)

2012-07-15T23:59:59.000Z

203

Low dose ionizing radiation induces tumor growth promoting factors in  

NLE Websites -- All DOE Office Websites (Extended Search)

ionizing radiation induces tumor growth promoting factors in ionizing radiation induces tumor growth promoting factors in stress-induced premature senescent fibroblasts David Boothman University of Texas Southwestern Medical Center at Dallas Abstract Recent evidence suggest that the causes of cancer development are not limited to mutations within cancer cells, but also involve in alterations of cancer microenvironment. Senescent cells are irreversibly growth arrested, but remain metabolically active. Senescent cells, especially senescent fibroblasts in the stroma may provide a beneficial environment for tumor growth through secretion of certain factors. Accumulation of senescent cells in the stroma of patients repeatedly exposed to low doses of IR or low dose rates of IR, could be an important factor, causing alteration of the microenvironment that ultimately benefits tumor

204

Rate Schedule CPP-2  

NLE Websites -- All DOE Office Websites (Extended Search)

or rate schedule accepted or approved by the Federal Energy Regulatory Commission (FERC) or other regulatory bodies will be passed on to each relevant customer. The FERC's or...

205

Demonstration of Advanced 3D ALARA Planning Prototypes for Dose Reduction  

Science Conference Proceedings (OSTI)

Three-dimensional (3D) imaging technology, radiation surveys, and real-time dose rate technology—all have benefits for their use when considered separately. Unique advantages can be realized if the technologies are used together. These advantages are primarily related to the presentation of the data in a more understandable way that may assist with identifying opportunities for dose reduction and control.BackgroundA typical radiation survey is ...

2012-12-21T23:59:59.000Z

206

Human Collagen Injections to Reduce Rectal Dose During Radiotherapy  

Science Conference Proceedings (OSTI)

Objectives: The continuing search for interventions, which address the incidence and grade of rectal toxicities associated with radiation treatment of prostate cancer, is a major concern. We are reporting an investigational trial using human collagen to increase the distance between the prostate and anterior rectal wall, thereby decreasing the radiation dose to the rectum. Methods: This is a pilot study evaluating the use of human collagen as a displacing agent for the rectal wall injected before starting a course of intensity-modulated radiotherapy (IMRT) for prostate cancer. Using a transperineal approach, 20 mL of human collagen was injected into the perirectal space in an outpatient setting. Computerized IMRT plans were performed pre- and postcollagen injection, and after a patient completed their radiotherapy, to determine radiation dose reduction to the rectum associated with the collagen injection. Computed tomography scans were performed 6 months and 12 months after completing their radiotherapy to evaluate absorption rate of the collagen. All patients were treated with IMRT to a dose of 75.6 Gy to the prostate. Results: Eleven patients were enrolled into the study. The injection of human collagen in the outpatient setting was well tolerated. The mean separation between the prostate and anterior rectum was 12.7 mm. The mean reduction in dose to the anterior rectal wall was 50%. All men denied any rectal symptoms during the study. Conclusions: The transperineal injection of human collagen for the purpose of tissue displacement is well tolerated in the outpatient setting. The increased separation between the prostate and rectum resulted in a significant decrease in radiation dose to the rectum while receiving IMRT and was associated with no rectal toxicities.

Noyes, William R., E-mail: noyes@cancercenternd.com [Department of Radiation Oncology, Cancer Center of North Dakota, Grand Forks, ND (United States); Hosford, Charles C. [Department of Medical Statistics, University of North Dakota School of Medicine, Grand Forks, ND (United States); Schultz, Steven E. [Department of Urology, RiverView Health, Grand Forks, ND (United States)

2012-04-01T23:59:59.000Z

207

Compensated count-rate circuit for radiation survey meter  

DOE Patents (OSTI)

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.

Todd, R.A.

1980-05-12T23:59:59.000Z

208

Improvements in dose accuracy delivered with static-MLC IMRT on an integrated linear accelerator control system  

Science Conference Proceedings (OSTI)

Purpose: Dose accuracy has been shown to vary with dose per segment and dose rate when delivered with static multileaf collimator (SMLC) intensity modulated radiation therapy (IMRT) by Varian C-series MLC controllers. The authors investigated the impact of monitor units (MUs) per segment and dose rate on the dose delivery accuracy of SMLC-IMRT fields on a Varian TrueBeam linear accelerator (LINAC), which delivers dose and manages motion of all components using a single integrated controller. Methods: An SMLC sequence was created consisting of ten identical 10 x 10 cm{sup 2} segments with identical MUs. Beam holding between segments was achieved by moving one out-of-field MLC leaf pair. Measurements were repeated for various combinations of MU/segment ranging from 1 to 40 and dose rates of 100-600 MU/min for a 6 MV photon beam (6X) and dose rates of 800-2400 MU/min for a 10 MV flattening-filter free photon (10XFFF) beam. All measurements were made with a Farmer (0.6 cm{sup 3}) ionization chamber placed at the isocenter in a solid-water phantom at 10 cm depth. The measurements were performed on two Varian LINACs: C-series Trilogy and TrueBeam. Each sequence was delivered three times and the dose readings for the corresponding segments were averaged. The effects of MU/segment, dose rate, and LINAC type on the relative dose variation ({Delta}{sub i}) were compared using F-tests ({alpha} = 0.05). Results: On the Trilogy, large {Delta}{sub i} was observed in small MU segments: at 1 MU/segment, the maximum {Delta}{sub i} was 10.1% and 57.9% at 100 MU/min and 600 MU/min, respectively. Also, the first segment of each sequence consistently overshot ({Delta}{sub i} > 0), while the last segment consistently undershot ({Delta}{sub i} dose rates greater than 100 MU/min. The linear trend of decreasing dose accuracy as a function of increasing dose rate on the Trilogy is no longer apparent on TrueBeam, even for dose rates as high as 2400 MU/min. Dose inaccuracy averaged over all ten segments in each beam delivery sequence was larger for Trilogy than TrueBeam, with the largest discrepancy (0.2% vs 3%) occurring for 1 MU/segment beams at both 300 and 600 MU/min. Conclusions: Earlier generations of Varian LINACs exhibited large dose variations for small MU segments in SMLC-IMRT delivery. Our results confirmed these findings. The dose delivery accuracy for SMLC-IMRT is significantly improved on TrueBeam compared to Trilogy for every combination of low MU/segment (1-10) and high dose rate (200-600 MU/min), in part due to the faster sampling rate (100 vs 20 Hz) and enhanced electronic integration of the MLC controller with the LINAC. SMLC-IMRT can be implemented on TrueBeam with higher dose accuracy per beam ({+-}0.2% vs {+-}3%) than previous generations of Varian C-series LINACs for 1 MU/segment delivered at 600 MU/min).

Li Ji; Wiersma, Rodney D.; Stepaniak, Christopher J.; Farrey, Karl J.; Al-Hallaq, Hania A. [Department of Radiation and Cellular Oncology, University of Chicago, 5758 South Maryland Avenue, MC9006, Chicago, Illinois 60637 (United States)

2012-05-15T23:59:59.000Z

209

Exchange Rates and Fundamentals  

E-Print Network (OSTI)

We show analytically that in a rational expectations present-value model, an asset price manifests near–random walk behavior if fundamentals are I(1) and the factor for discounting future fundamentals is near one. We argue that this result helps explain the well-known puzzle that fundamental variables such as relative money supplies, outputs, inflation, and interest rates provide little help in predicting changes in floating exchange rates. As well, we show that the data do exhibit a related link suggested by standard models—that the exchange rate helps predict these fundamentals. The implication is that exchange rates and fundamentals are linked in a way that is broadly consistent with asset-pricing models of the exchange rate. I.

Charles Engel; Kenneth D. West

2005-01-01T23:59:59.000Z

210

Kinetic Mechanism and Rate-Limiting Steps of Focal Adhesion Kinase-1  

SciTech Connect

Steady-state kinetic analysis of focal adhesion kinase-1 (FAK1) was performed using radiometric measurement of phosphorylation of a synthetic peptide substrate (Ac-RRRRRRSETDDYAEIID-NH{sub 2}, FAK-tide) which corresponds to the sequence of an autophosphorylation site in FAK1. Initial velocity studies were consistent with a sequential kinetic mechanism, for which apparent kinetic values k{sub cat} (0.052 {+-} 0.001 s{sup -1}), K{sub MgATP} (1.2 {+-} 0.1 {micro}M), K{sub iMgATP} (1.3 {+-} 0.2 {micro}M), K{sub FAK-tide} (5.6 {+-} 0.4 {micro}M), and K{sub iFAK-tide} (6.1 {+-} 1.1 {micro}M) were obtained. Product and dead-end inhibition data indicated that enzymatic phosphorylation of FAK-tide by FAK1 was best described by a random bi bi kinetic mechanism, for which both E-MgADP-FAK-tide and E-MgATP-P-FAK-tide dead-end complexes form. FAK1 catalyzed the {beta}{gamma}-bridge:{beta}-nonbridge positional oxygen exchange of [{gamma}-{sup 18}O{sub 4}]ATP in the presence of 1 mM [{gamma}-{sup 18}O{sub 4}]ATP and 1.5 mM FAK-tide with a progressive time course which was commensurate with catalysis, resulting in a rate of exchange to catalysis of k{sub x}/k{sub cat} = 0.14 {+-} 0.01. These results indicate that phosphoryl transfer is reversible and that a slow kinetic step follows formation of the E-MgADP-P-FAK-tide complex. Further kinetic studies performed in the presence of the microscopic viscosogen sucrose revealed that solvent viscosity had no effect on k{sub cat}/K{sub FAK-tide}, while k{sub cat} and k{sub cat}/K{sub MgATP} were both decreased linearly at increasing solvent viscosity. Crystallographic characterization of inactive versus AMP-PNP-liganded structures of FAK1 showed that a large conformational motion of the activation loop upon ATP binding may be an essential step during catalysis and would explain the viscosity effect observed on k{sub cat}/K{sub m} for MgATP but not on k{sub cat}/K{sub m} for FAK-tide. From the positional isotope exchange, viscosity, and structural data it may be concluded that enzyme turnover (k{sub cat}) is rate-limited by both reversible phosphoryl group transfer (k{sub forward} {approx} 0.2 s{sup -1} and k{sub reverse} {approx} 0.04 s{sup -1}) and a slow step (k{sub conf} {approx} 0.1 s{sup -1}) which is probably the opening of the activation loop after phosphoryl group transfer but preceding product release.

Schneck, Jessica L.; Briand, Jacques; Chen, Stephanie; Lehr, Ruth; McDevitt, Patrick; Zhao, Baoguang; Smallwood, Angela; Concha, Nestor; Oza, Khyati; Kirkpatrick, Robert; Yan, Kang; Villa, James P.; Meek, Thomas D.; Thrall, Sara H. (Chemizon); (GSKPA)

2010-12-07T23:59:59.000Z

211

An updated dose assessment for Rongelap Island  

Science Conference Proceedings (OSTI)

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).

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

1994-07-01T23:59:59.000Z

212

Low Dose Radiation Research Program: About  

NLE Websites -- All DOE Office Websites (Extended Search)

About About Background. Extensive research on the health effects of radiation using standard epidemiological and toxicological approaches has been done for decades to characterize responses of populations and individuals to high radiation doses, and to set exposure standards to protect both the public and the workforce. These standards were set using models that extrapolated from the cancers observed following exposure to high doses of radiation to predicted, but not measurable, changes in cancer frequency at low radiation doses. The use of models was necessary because of our inability to detect changes in cancer incidence following low doses of radiation. Historically, the predominant approach has been the Linear-no-Threshold model (see Wikipedia entry) and collective dose concept that assumes each unit of radiation, no

213

Estimating the risk associated with computerized tomography doses  

SciTech Connect

The largest annual whole- body dose to the US population from man-made radiation is from medical sources. According to the BEIR report, the use of diagnostic x-rays by the medical profession has increased in recent years at an annual rate of 1 to 4%. Risk factors developed by the BEIR committee can be used to estimate the risk to the population due to the exposure incurred through medical radiography. In this paper, these risk factors are employed to obtain an estimate of risk due to radiation exposure from computerized tomography (CT).

Yalcintas, M.G.; Leggett, R.W.; Dunning, D.E.; Nalcioglu, O.

1979-01-01T23:59:59.000Z

214

OpenEI - rates  

Open Energy Info (EERE)

U.S. Electric Utility U.S. Electric Utility Companies and Rates: Look-up by Zipcode (Feb 2011) http://en.openei.org/datasets/node/899 This dataset, compiled by NREL and Ventyx, provides average residential, commercial and industrial electricity rates by zip code for both investor owned utilities (IOU) and non-investor owned utilities. Note: the file includes average rates for each utility, but not the detailed rate structure data found in the database available via the zip-code look-up feature on the OpenEI Utilities page (http://en.openei.org/wiki/Gateway:Utilities). The data was released by NREL/Ventyx in February 2011.

215

<RatesMiscInfo>  

NLE Websites -- All DOE Office Websites (Extended Search)

Rates MISCELLANEOUS INFORMATION Power Supply Report June 2013 (53kb pdf) May 2013 (53kb pdf) April 2013 (52kb pdf) March 2013 (54kb pdf) February 2013 (54kb pdf) January 2013 (54kb...

216

Heat Rate Program Guidelines  

Science Conference Proceedings (OSTI)

Power plant facilities with performance or heat rate improvement programs perform better than those that do not have those programs. A heat rate improvement program typically provides sufficient information for decision making with respect to timely maintenance actions and/or operational adjustments. Monitoring the performance of any power plant component includes the trending of parameters that also describe the performance of other plant components, providing insight and information on improving ...

2012-12-31T23:59:59.000Z

217

Cat Heart Rate Monitoring  

NLE Websites -- All DOE Office Websites (Extended Search)

Cat Heart Rate Monitoring Cat Heart Rate Monitoring Name: Shakti Status: student Grade: 9-12 Location: TX Country: USA Date: Summer 2010 Question: What is the best way to find a cat's heart rate using a stethoscope? Because I have tried to hear their heart beat but their purring is all I can hear. If I shouldn't use a stethoscope, then what should I use? Replies: Hi Shakti! If you want to use a stethoscope, the trick is to get your cat to stop purring. Two good ways that I have found to help stop the purring 1. Cover their nose (generally cats don't like this and will stop purring) or 2. Put on the tap to drip or lightly stream water (also, they generally don't like this and will stop purring). Alternatively, you can get their heart rate from feeling their pulse. A good place to try to feel a pulse is right where the leg attaches to the abdomen - in an area called the inguinal region. Now granted there are some heart conditions that will cause an animals pulse and their heart rates don't match up, and it's hard to feel if you have a fat cat, but it's a good place to try if you are really trying to get a heart rate in a healthy kitty!

218

Real-time automatic interpolation of ambient gamma dose rates from the Dutch radioactivity monitoring network  

Science Conference Proceedings (OSTI)

Detection of radiological accidents and monitoring the spread of the contamination is of great importance. Following the Chernobyl accident many European countries have installed monitoring networks to perform this task. Real-time availability of automatically ... Keywords: Automatic interpolation, Interoperability, Kriging, Monitoring networks, Web services

Paul H. Hiemstra; Edzer J. Pebesma; Chris J. W. Twenhöfel; Gerard B. M. Heuvelink

2009-08-01T23:59:59.000Z

219

Dose Rate Analyses for the High Energy Beam Transport Section of IFMIF  

Science Conference Proceedings (OSTI)

IFMIF / Proceedings of the Fifteenth International Conference on Fusion Reactor Materials, Part A: Fusion Technology

Keitaro Kondo; Ulrich Fischer; Volker Heinzel; Axel Klix; Arkady Serikov

220

Inverse planning for low-dose-rate prostate brachytherapy by simulated annealing under fuzzy expert control  

Science Conference Proceedings (OSTI)

Simulated annealing (SA) is a multivariate combinatorial optimization process that searches the configuration space of possible solutions by a random walk

Alberto de la Zerda Lerner

2004-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "beta-gamma dose rates" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


221

Neutron Dose Rate Effect on Radiation Hardening of Type 316L ...  

Science Conference Proceedings (OSTI)

NRC/EPRI Welding Residual Stress Validation Program (Phase III) · On the Microstructure of Alloy 600 SCC Cracks Observed by TEM on PWR SG Pulled Tubes ...

222

Fusion Engineering and Design 42 (1998) 155172 Assessment of dose rate profiles and accessibility inside the  

E-Print Network (OSTI)

· Tritium Processing · Magnet Technology · High-Heat-Flux Component Development · Remote Handling Technology for cut and re-welding in the Hot Cell ­ Analysis of erosion of the ITER first wall due to plasma-facing components ­ Tritium inventory control ­ Remote maintenance ­ Fueling, heating, and current drive control

Abdou, Mohamed

223

Radiological Dose Calculations for Fusion Facilities  

Science Conference Proceedings (OSTI)

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.

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

2003-04-01T23:59:59.000Z

224

Trade, Interdependence and Exchange Rates  

E-Print Network (OSTI)

period is 1971-2000. All inflation rates and predictions areof Goods and Real Exchange Rate Fluc- tuations,” mimeo [5]Between Trade and Exchange Rate Volatility,” mimeo [6

Fitzgerald, Doireann

2004-01-01T23:59:59.000Z

225

Exchange Rates, Information, and Crises  

E-Print Network (OSTI)

3 Intervention and Exchange Rate Misalignment 4 Conclusion 5explain the exchange rate determination puzzle? Americanrisk to defend the exchange rate. Universit¨at Trier Working

Fernholz, Ricardo Turrin

2011-01-01T23:59:59.000Z

226

A standard dose of radiation for microscopic disease is not appropriate  

SciTech Connect

Elective irradiation of sites of potential occult tumor spread is often part of a patient's radiation therapy program. The required radiation dose (D) depends on the probability that occult disease exists (P(occ)), the number of sites at risk (A), the number of tumor clonogens present (Ni), their radiation sensitivity, and the desired control rate. An exponential model of cell survival is used to quantify the importance of these factors. Control Probability = (1 - Pocc x (1 - e-Ni x (SF2)D/2))A; SF2 = surviving fraction after 2 Gy. Implications for clinical radiation therapy include: 1. Since the number of clonogens in an occult site may vary from 10 degrees to 10(8), Ni is the major determinant of the required dose. The intrinsic radiation sensitivity of the clonogens (SF2) is also extremely important in determining the dose. Other factors are less influential since they vary less. 2. The variability of Ni (8 logs) is larger than the variation in cell number seen with gross disease (1 cm3 versus 1000 cm3, 3 logs). When Ni approximately 10(8), the required dose approaches that needed for small volume gross disease (10(9) cells, 1 cm3). 3. The dose prescribed to elective sites should reflect the risk of occult disease based on the primary tumor site, stage, and grade. 4. Regions where clinicoradiologic evaluation is difficult (e.g., pelvis and obese neck) require higher doses because macroscopic tumor deposits may exist. 5. Relatively low doses (10 to 30 Gy) are often thought to be inadequate for microscopic tumor. However, similar doses have been reported to sterilize microscopic tumor in ovarian, rectal, bladder, breast, and head and neck carcinomas. Relatively low doses should not be discounted since they may be useful in select cases when normal tissue tolerances and/or previous irradiation treatment limit the radiation dose.

Marks, L.B. (Duke Univ. Medical Center, Durham, NC (USA))

1990-12-15T23:59:59.000Z

227

Dose reduction in LDR brachytherapy by implanted prostate gold fiducial markers  

Science Conference Proceedings (OSTI)

Purpose: The dosimetric impact of gold fiducial markers (FM) implanted prior to external beam radiotherapy of prostate cancer on low dose rate (LDR) brachytherapy seed implants performed in the context of combined therapy was investigated. Methods: A virtual water phantom was designed containing a single FM. Single and multi source scenarios were investigated by performing Monte Carlo dose calculations, along with the influence of varying orientation and distance of the FM with respect to the sources. Three prostate cancer patients treated with LDR brachytherapy for a recurrence following external beam radiotherapy with implanted FM were studied as surrogate cases to combined therapy. FM and brachytherapy seeds were identified on post implant CT scans and Monte Carlo dose calculations were performed with and without FM. The dosimetric impact of the FM was evaluated by quantifying the amplitude of dose shadows and the volume of cold spots. D{sub 90} was reported based on the post implant CT prostate contour. Results: Large shadows are observed in the single source-FM scenarios. As expected from geometric considerations, the shadows are dependent on source-FM distance and orientation. Large dose reductions are observed at the distal side of FM, while at the proximal side a dose enhancement is observed. In multisource scenarios, the importance of shadows appears mitigated, although FM at the periphery of the seed distribution caused underdosage (dose). In clinical cases, the FM reduced the dose to some voxels by up to 50% and generated shadows with extents of the order of 4 mm. Within the prostate contour, cold spots (dose) of the order of 20 mm{sup 3} were observed. D{sub 90} proved insensitive to the presence of FM for the cases selected. Conclusions: There is a major local impact of FM present in LDR brachytherapy seed implant dose distributions. Therefore, reduced tumor control could be expected from FM implanted in tumors, although our results are too limited to draw conclusions regarding clinical significance.

Landry, Guillaume; Reniers, Brigitte; Lutgens, Ludy; Murrer, Lars; Afsharpour, Hossein; Haas-Kock, Danielle de; Visser, Peter; Gils, Francis van; Verhaegen, Frank [Department of Radiation Oncology (MAASTRO), GROW-School for Oncology and Developmental Biology, Maastricht University Medical Center, Maastricht (Netherlands); Departement de Physique, de Genie Physique et d'Optique, Universite Laval, Quebec (Canada) and Departement de Radio-Oncologie et Centre de Recherche en Cancerologie, Universite Laval, CHUQ Pavillon L'Hotel-Dieu de Quebec, Quebec (Canada); Department of Radiation Oncology (MAASTRO), GROW-School for Oncology and Developmental Biology, Maastricht University Medical Center, Maastricht (Netherlands); Department of Radiation Oncology (MAASTRO), GROW-School for Oncology and Developmental Biology, Maastricht University Medical Center, Maastricht (Netherlands) and Department of Oncology, McGill University, Montreal (Canada)

2012-03-15T23:59:59.000Z

228

Mythology of rate design  

SciTech Connect

If power rates are determined by marginal costs with clear signals to the consumer, then the load curve will regulate itself without burdening the public with ethical and patriotic issues. Manipulation of the load factor will only cause hardship and inconvenience, but a choice of rates will allow consumers to determine their own balance between rates and convenience. It makes sense to charge consumers the true cost rather than having the same rate apply during a 24-hour period when costs are not uniform. Discussions of how to determine equitable rate structures flounder because we cannot define equity. Economists, who base their recommendations on the assumption that income distribution is reasonable, believe marginal-cost pricing allows the customer to save whatever the utility is saving. Such a system is economically efficient in that the utility charges 100 percent-load-factor consumers according to a base load plant, while charging peak and offpeak consumers what it costs to add them to the system. Adjustment of prices to cause a minimal distortion of the market is the economists' general rule for handling the balancing of cost increases and regulated profits. (DCK)

Streiter, S.H.

1977-01-01T23:59:59.000Z

229

Capstone Depleted Uranium Aerosol Biokinetics, Concentrations, and Doses  

SciTech Connect

One of the principal goals of the Capstone Depleted Uranium (DU) Aerosol Study was to quantify and characterize DU aerosols generated inside armored vehicles by perforation with a DU penetrator. This study consequently produced a database in which the DU aerosol source terms were specified both physically and chemically for a variety of penetrator-impact geometries and conditions. These source terms were used to calculate radiation doses and uranium concentrations for various scenarios as part of the Capstone DU Human Health Risk Assessment (HHRA). This paper describes the scenario-related biokinetics of uranium, and summarizes intakes, chemical concentrations to the organs, and E(50) and HT(50) for organs and tissues based on exposure scenarios for personnel in vehicles at the time of perforation as well as for first responders. For a given exposure scenario (duration time and breathing rates), the range of DU intakes among the target vehicles and shots was not large, about a factor of 10, with the lowest being from a ventilated operational Abrams tank and the highest being for an unventilated Abrams with DU penetrator perforating DU armor. The ranges of committed effective doses were more scenario-dependent than were intakes. For example, the largest range, a factor of 20, was shown for scenario A, a 1-min exposure, whereas, the range was only a factor of two for the first-responder scenario (E). In general, the committed effective doses were found to be in the tens of mSv. The risks ascribed to these doses are discussed separately.

Guilmette, Raymond A.; Miller, Guthrie; Parkhurst, MaryAnn

2009-02-26T23:59:59.000Z

230

Hanford Environmental Dose Reconstruction Project monthly report  

Science Conference Proceedings (OSTI)

The objective of the Hanford Environmental Dose Reconstruction MDR) 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 envirorunental pathways. epidemiology, surface-water transport, ground-water transport, statistics, demography, agriculture, meteorology, nuclear engineering. radiation dosimetry. and cultural anthropology. Included are appointed 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.

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

1992-09-01T23:59:59.000Z

231

Hanford Environmental Dose Reconstruction Project. Monthly report  

Science Conference Proceedings (OSTI)

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.

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

1992-07-01T23:59:59.000Z

232

Low Dose Radiation Research Program: Mina Bissell  

NLE Websites -- All DOE Office Websites (Extended Search)

Abstracts 2006 Workshop: 3D Tissue Models for the Study of the Effects of Low-Dose Irradiation Nelson, C.M., Fata, J E., Kenny, P.A., and Bissell, M.J. Publications Kumari, I.,...

233

Low Dose Radiation Research Program: David Nelson  

NLE Websites -- All DOE Office Websites (Extended Search)

L.E., Nelson, D., Sorensen, K., Tucker, J.D., and Wyrobek, A.J. (2005). Low-dose irradiation alters the transcript profiles of human lymphoblasoid cells, including genes...

234

Low Dose Radiation Research Program: Thomas Weber  

NLE Websites -- All DOE Office Websites (Extended Search)

2005 Workshop: A Paracrine Signal Mediates The Cell Transformation Response To Low Dose Gamma Radiation in JB6 Cells. Weber, T.J., Siegel, R.W., Markillie, L.M., Chrisler,...

235

Low Dose Radiation Research Program: Molecular Characterization...  

NLE Websites -- All DOE Office Websites (Extended Search)

the Role of SOD Genes in Mammalian Cellular Response to Low Dose Ionizing Radiation Chaun-Yuan Li Duke University Medical Center Durham, NC Why this Project? To evaluate the roles...

236

Low Dose Radiation Research Program: Micronutrient Deficiency...  

NLE Websites -- All DOE Office Websites (Extended Search)

DNA damage is appreciable and increases with age,3;4 Our aim is to compare low dose radiation with micronutrient deficiency, and endogenous damage by a variety of measures...

237

BCP Annual Rate Process  

NLE Websites -- All DOE Office Websites (Extended Search)

2013 BCP Annual Rate Process 2013 BCP Annual Rate Process Informal Process Rate Activity Schedule (doc) Informal Customer Meeting Thursday March 6, 2013 at 10:30 A.M. Conf Rms 3&4 Informal Customer Meeting Presentation (Pdf) PRS Executive Summary (Mar 07, 2013) (Pdf) FY2014 Final Ten Year Operating Plan PRS Executive Summary (PDF) FORM for Foreign Visits (doc) Formal Process Initial Federal Register Notice (pdf) Public Information Forum March 27,2013 at 10:30 A.M. Conf Rms3&4 Customer Meeting Presentation PIF Presentation (PPT) Presentation Details (pdf) Reclamation Fund Status Report PIF PRS Executive Summary (pdf) PIF Transcripts (PDF) Visitor Center Cost Analysis Questions - Responses Public Comment Forum April 10, 2013 at 10:30 A.M. Conf Rms3&4 PCF Transcripts Customer Letters

238

Multiple System Rate Process  

NLE Websites -- All DOE Office Websites (Extended Search)

DSW Multiple System Transmission Rate Process DSW Multiple System Transmission Rate Process Federal Register Notice Withdrawing Rate Proposal (PDF) Formal Process Extension Federal Register Notice (PDF) Customer Savings Under Various MSTR (XLS) Public Information Forum March 29, 2005 Customer Meeting Overview (Power Point) Customer Meeting Overview (PDF) Customer Meeting Transcript (PDF) Public Comment Forum April 6, 2005 Customer Meeting Transcript (PDF) Response Letter 5-17-05 (PDF) Customer Letters Tonopah ID-5/25/05 (PDF) APS-5/26/05 (PDF) SRP-5/27/05 (PDF) RSLynch-6/1/05 (PDF) KRSaline-6/1/05 (PDF) Formal Process Federal Register Notice (Word) Federal Register Notice (PDF) Brochure (Word) Appendices to Brochure: A B C D E1 E2 F1 F2 GH Public Information Forum July 14, 2004 Customer Meeting Overview (Power Point)

239

Upper Great Plains Rates information  

NLE Websites -- All DOE Office Websites (Extended Search)

Rates and Repayment Services Rates and Repayment Services Rates 2010 Firm Power Rate (effective January 1, 2010) Rate Adjustments 2010 Firm Power Rate Adjustment 2009 Firm Power Rate Adjustment IS Rate Adjustments Rate Adjustment Process Rate Orders Signed, December 23, 2009 (16kb pdf) Announcements Firm Electric Service Customer Letter - Preliminary Review of Drought Adder Component, June 27, 2013 (74kb pdf) Customer Letter - Final Notice of Drought Adder Component, October 2, 2013 (68kb pdf) Integrated System (IS) Rates 2014 IS Rates Customer Information Meeting Presentation, October 15, 2013 (611kb pdf) Customer Letter - Notification of 2014 Rates, September 13, 2013 (160kb pdf) 2014 Transmission and Ancillary Services Rate Calculation and 2012 Rate True-up Calculation (4.9mb pdf) 2013 IS Rates

240

DOSE TO CURIE DETERMINATION FOR CONTAINERS WITH MEASURABLE CS-137  

Science Conference Proceedings (OSTI)

The Next Generation Retrieval (NGR) project will retrieve suspect transuranic (TRU) waste containers from Trenches 17 and 27 in the 218-E-12B (12B) burial ground. The trenches were in operation from May 1970 through October 1972. A portion of the retrieved containers that will require shipment to and acceptance at a treatment, storage, and disposal (TSD) facility and the containers will be either remote-handled (RH) and/or contact-handled (CH). The method discussed in this document will be used for the RH and some of the CH containers to determine the radionuclide inventory. Waste disposition (shipment and TSD acceptance) requires that the radioactive content be characterized for each container. Source-term estimates using high resolution, shielded, gamma-ray scan assay techniques cannot be performed on a number of RH and other containers with high dose rates from {sup 137}Cs-{sup 137m}Ba. This document provides the method to quantify the radioactive inventory of fission product gamma emitters within the containers based on the surface dose rate measurements taken in the field with hand-held survey instruments.

RATHBUN LA; ANDERSON JD; SWAN RJ

2010-12-03T23:59:59.000Z

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241

Low Dose Responses in Human Cells and Molecular Mechanisms of Adaptation  

NLE Websites -- All DOE Office Websites (Extended Search)

Responses in Human Cells and Molecular Mechanisms of Adaptation Responses in Human Cells and Molecular Mechanisms of Adaptation Joe Gray Priscilla Cooper Lawrence Berkeley National Laboratory Abstract The radiation Adaptive Response (adaptation, or AR) is a well documented, although evidently highly variable, protective phenomenon in which exposures to low-dose or low-dose-rate ionizing radiation result in reduced deleterious effects of subsequent higher exposures. Protection has been reported against a variety of biologically important endpoints, but its variability as a function of cell and tissue type and its genetic control are not well understood. The adaptive response is predicted to result in a non-linear dose response for cancer risk in the low dose range. However, the molecular mechanism(s) remain unknown, and such information is

242

A method of dose reconstruction for moving targets compatible with dynamic treatments  

SciTech Connect

Purpose: To develop a method that allows a commercial treatment planning system (TPS) to perform accurate dose reconstruction for rigidly moving targets and to validate the method in phantom measurements for a range of treatments including intensity modulated radiation therapy (IMRT), volumetric arc therapy (VMAT), and dynamic multileaf collimator (DMLC) tracking. Methods: An in-house computer program was developed to manipulate Dicom treatment plans exported from a TPS (Eclipse, Varian Medical Systems) such that target motion during treatment delivery was incorporated into the plans. For each treatment, a motion including plan was generated by dividing the intratreatment target motion into 1 mm position bins and construct sub-beams that represented the parts of the treatment that were delivered, while the target was located within each position bin. For each sub-beam, the target shift was modeled by a corresponding isocenter shift. The motion incorporating Dicom plans were reimported into the TPS, where dose calculation resulted in motion including target dose distributions. For experimental validation of the dose reconstruction a thorax phantom with a moveable lung equivalent rod with a tumor insert of solid water was first CT scanned. The tumor insert was delineated as a gross tumor volume (GTV), and a planning target volume (PTV) was formed by adding margins. A conformal plan, two IMRT plans (step-and-shoot and sliding windows), and a VMAT plan were generated giving minimum target doses of 95% (GTV) and 67% (PTV) of the prescription dose (3 Gy). Two conformal fields with MLC leaves perpendicular and parallel to the tumor motion, respectively, were generated for DMLC tracking. All treatment plans were delivered to the thorax phantom without tumor motion and with a sinusoidal tumor motion. The two conformal fields were delivered with and without portal image guided DMLC tracking based on an embedded gold marker. The target dose distribution was measured with a radiochromic film in the moving rod and compared with the reconstructed doses using gamma tests. Results: Considerable interplay effects between machine motion and target motion were observed for the treatments without tracking. For nontracking experiments, the mean 2 mm/2% gamma pass rate over all investigated scenarios was 99.6% between calculated and measured doses. For tracking experiments, the mean gamma pass rate was 99.4%. Conclusions: A method for accurate dose reconstruction for moving targets with dynamic treatments was developed and experimentally validated in a variety of delivery scenarios. The method is suitable for integration into TPSs, e.g., for reconstruction of the dose delivered to moving tumors or calculation of target doses delivered with DMLC tracking.

Rugaard Poulsen, Per; Lykkegaard Schmidt, Mai; Keall, Paul; Schjodt Worm, Esben; Fledelius, Walther; Hoffmann, Lone [Department of Oncology, Aarhus University Hospital, Norrebrogade 44, 8000 Aarhus C, Institute of Clinical Medicine, Aarhus University, Brendstrupgaardsvej 100, 8200 Aarhus N (Denmark); Department of Physics and Astronomy, Aarhus University, Ny Munkegade 120, 8000 Aarhus C (Denmark); Radiation Physics Laboratory, Sydney Medical School, University of Sydney, NSW 2006 (Australia); Department of Oncology, Aarhus University Hospital, Norrebrogade 44, 8000 Aarhus C, Department of Medical Physics, Aarhus University Hospital, Norrebrogade 44, 8000 Aarhus C (Denmark); Department of Oncology, Aarhus University Hospital, Norrebrogade 44, 8000 Aarhus C (Denmark); Department of Medical Physics, Aarhus University Hospital, Norrebrogade 44, 8000 Aarhus C (Denmark)

2012-10-15T23:59:59.000Z

243

High-dose MVCT image guidance for stereotactic body radiation therapy  

Science Conference Proceedings (OSTI)

Purpose: Stereotactic body radiation therapy (SBRT) is a potent treatment for early stage primary and limited metastatic disease. Accurate tumor localization is essential to administer SBRT safely and effectively. Tomotherapy combines helical IMRT with onboard megavoltage CT (MVCT) imaging and is well suited for SBRT; however, MVCT results in reduced soft tissue contrast and increased image noise compared with kilovoltage CT. The goal of this work was to investigate the use of increased imaging doses on a clinical tomotherapy machine to improve image quality for SBRT image guidance. Methods: Two nonstandard, high-dose imaging modes were created on a tomotherapy machine by increasing the linear accelerator (LINAC) pulse rate from the nominal setting of 80 Hz, to 160 Hz and 300 Hz, respectively. Weighted CT dose indexes (wCTDIs) were measured for the standard, medium, and high-dose modes in a 30 cm solid water phantom using a calibrated A1SL ion chamber. Image quality was assessed from scans of a customized image quality phantom. Metrics evaluated include: contrast-to-noise ratios (CNRs), high-contrast spatial resolution, image uniformity, and percent image noise. In addition, two patients receiving SBRT were localized using high-dose MVCT scans. Raw detector data collected after each scan were used to reconstruct standard-dose images for comparison. Results: MVCT scans acquired using a pitch of 1.0 resulted in wCTDI values of 2.2, 4.7, and 8.5 cGy for the standard, medium, and high-dose modes respectively. CNR values for both low and high-contrast materials were found to increase with the square root of dose. Axial high-contrast spatial resolution was comparable for all imaging modes at 0.5 lp/mm. Image uniformity was improved and percent noise decreased as the imaging dose increased. Similar improvements in image quality were observed in patient images, with decreases in image noise being the most notable. Conclusions: High-dose imaging modes are made possible on a clinical tomotherapy machine by increasing the LINAC pulse rate. Increasing the imaging dose results in increased CNRs; making it easier to distinguish the boundaries of low contrast objects. The imaging dose levels observed in this work are considered acceptable at our institution for SBRT treatments delivered in 3-5 fractions.

Westerly, David C.; Schefter, Tracey E.; Kavanagh, Brian D.; Chao, Edward; Lucas, Dan; Flynn, Ryan T.; Miften, Moyed [Department of Radiation Oncology, University of Colorado School of Medicine, Aurora, Colorado 80045 (United States); Accuray Inc., Madison, Wisconsin 53717 (United States); Department of Radiation Oncology, University of Iowa Hospitals and Clinics, Iowa City, Iowa 52242 (United States); Department of Radiation Oncology, University of Colorado School of Medicine, Aurora, Colorado 80045 (United States)

2012-08-15T23:59:59.000Z

244

Natural Gas Conveyance and Rates  

Reports and Publications (EIA)

Natural gas transportation market; Competition vs. market power; Rate structures Cost-of-service Performance based rates

Information Center

2001-02-01T23:59:59.000Z

245

LAP Transmission Rate  

NLE Websites -- All DOE Office Websites (Extended Search)

LAP Transmission Rate 4.50 4.00 3.82 3.50 3.00 of 2.50 c 0 2.I2 2.68 I 3: 2.00 1.50 1.00 0.50 0.00 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012...

246

Low or High Fractionation Dose {beta}-Radiotherapy for Pterygium? A Randomized Clinical Trial  

Science Conference Proceedings (OSTI)

Purpose: Postoperative adjuvant treatment using {beta}-radiotherapy (RT) is a proven technique for reducing the recurrence of pterygium. A randomized trial was conducted to determine whether a low fractionation dose of 2 Gy within 10 fractions would provide local control similar to that after a high fractionation dose of 5 Gy within 7 fractions for surgically resected pterygium. Methods: A randomized trial was conducted in 200 patients (216 pterygia) between February 2006 and July 2007. Only patients with fresh pterygium resected using a bare sclera method and given RT within 3 days were included. Postoperative RT was delivered using a strontium-90 eye applicator. The pterygia were randomly treated using either 5 Gy within 7 fractions (Group 1) or 2 Gy within 10 fractions (Group 2). The local control rate was calculated from the date of surgery. Results: Of the 216 pterygia included, 112 were allocated to Group 1 and 104 to Group 2. The 3-year local control rate for Groups 1 and 2 was 93.8% and 92.3%, respectively (p = .616). A statistically significant difference for cosmetic effect (p = .034), photophobia (p = .02), irritation (p = .001), and scleromalacia (p = .017) was noted in favor of Group 2. Conclusions: No better local control rate for postoperative pterygium was obtained using high-dose fractionation vs. low-dose fractionation. However, a low-dose fractionation schedule produced better cosmetic effects and resulted in fewer symptoms than high-dose fractionation. Moreover, pterygia can be safely treated in terms of local recurrence using RT schedules with a biologic effective dose of 24-52.5 Gy{sub 10.}.

Viani, Gustavo Arruda, E-mail: gusviani@gmail.com [Department of Radiation Oncology, Marilia Medicine School, Sao Paulo, SP (Brazil); De Fendi, Ligia Issa; Fonseca, Ellen Carrara [Department of Ophthalmology, Marilia Medicine School, Sao Paulo, SP (Brazil); Stefano, Eduardo Jose [Department of Radiation Oncology, Marilia Medicine School, Sao Paulo, SP (Brazil)

2012-02-01T23:59:59.000Z

247

Slide Rule for Rapid Response Estimation of Radiological Dose from Criticality Accidents  

SciTech Connect

This paper describes a functional slide rule that provides a readily usable ?in-hand? method for estimating nuclear criticality accident information from sliding graphs, thereby permitting (1) the rapid estimation of pertinent criticality accident information without laborious or sophisticated calculations in a nuclear criticality emergency situation, (2) the appraisal of potential fission yields and external personnel radiation exposures for facility safety analyses, and (3) a technical basis for emergency preparedness and training programs at nonreactor nuclear facilities. The slide rule permits the estimation of neutron and gamma dose rates and integrated doses based upon estimated fission yields, distance from the fission source, and time-after criticality accidents for five different critical systems. Another sliding graph permits the estimation of critical solution fission yields based upon fissile material concentration, critical vessel geometry, and solution addition rate. Another graph provides neutron and gamma dose-reduction factors for water, steel, and concrete shields.

Broadhead, B.L.; Childs, R.L.; Hopper, C.M.; Parks, C.V.

1999-09-20T23:59:59.000Z

248

Automated size-specific CT dose monitoring program: Assessing variability in CT dose  

SciTech Connect

Purpose: The potential health risks associated with low levels of ionizing radiation have created a movement in the radiology community to optimize computed tomography (CT) imaging protocols to use the lowest radiation dose possible without compromising the diagnostic usefulness of the images. Despite efforts to use appropriate and consistent radiation doses, studies suggest that a great deal of variability in radiation dose exists both within and between institutions for CT imaging. In this context, the authors have developed an automated size-specific radiation dose monitoring program for CT and used this program to assess variability in size-adjusted effective dose from CT imaging. Methods: The authors radiation dose monitoring program operates on an independent health insurance portability and accountability act compliant dosimetry server. Digital imaging and communication in medicine routing software is used to isolate dose report screen captures and scout images for all incoming CT studies. Effective dose conversion factors (k-factors) are determined based on the protocol and optical character recognition is used to extract the CT dose index and dose-length product. The patient's thickness is obtained by applying an adaptive thresholding algorithm to the scout images and is used to calculate the size-adjusted effective dose (ED{sub adj}). The radiation dose monitoring program was used to collect data on 6351 CT studies from three scanner models (GE Lightspeed Pro 16, GE Lightspeed VCT, and GE Definition CT750 HD) and two institutions over a one-month period and to analyze the variability in ED{sub adj} between scanner models and across institutions. Results: No significant difference was found between computer measurements of patient thickness and observer measurements (p= 0.17), and the average difference between the two methods was less than 4%. Applying the size correction resulted in ED{sub adj} that differed by up to 44% from effective dose estimates that were not adjusted by patient size. Additionally, considerable differences were noted in ED{sub adj} distributions between scanners, with scanners employing iterative reconstruction exhibiting significantly lower ED{sub adj} (range: 9%-64%). Finally, a significant difference (up to 59%) in ED{sub adj} distributions was observed between institutions, indicating the potential for dose reduction. Conclusions: The authors developed a robust automated size-specific radiation dose monitoring program for CT. Using this program, significant differences in ED{sub adj} were observed between scanner models and across institutions. This new dose monitoring program offers a unique tool for improving quality assurance and standardization both within and across institutions.

Christianson, Olav; Li Xiang; Frush, Donald; Samei, Ehsan [Clinical Imaging Physics Group, Department of Radiology, Duke University Medical Center, Durham, North Carolina 27705 and Department of Radiology, Duke University Medical Center, Durham, North Carolina 27705 (United States); Clinical Imaging Physics Group, Department of Radiology, Duke University Medical Center, Durham, North Carolina 27705 (United States); Department of Radiology, Duke University Medical Center, Durham, North Carolina 27705 (United States) and Carl E. Ravin Advanced Imaging Laboratories, Department of Radiology, Duke University Medical Center, Durham, North Carolina 27705 (United States); Department of Radiology, Duke University Medical Center, Durham, North Carolina 27705 (United States); Clinical Imaging Physics Group, Department of Radiology, Duke University Medical Center, Durham, North Carolina 27705 (United States); Department of Radiology, Duke University Medical Center, Durham, North Carolina 27705 (United States); Carl E. Ravin Advanced Imaging Laboratories, Department of Radiology, Duke University Medical Center, Durham, North Carolina 27705 (United States); Medical Physics Graduate Program, Duke University, Durham, North Carolina 27705 (United States); Department of Physics, Duke University, Durham, North Carolina 27710 (United States); and Department of Biomedical Engineering, Duke University, Durham, North Carolina 27708 (United States)

2012-11-15T23:59:59.000Z

249

Gamma-ray spectra and doses from the Little Boy replica  

SciTech Connect

Most radiation safety guidelines in the nuclear industry are based on the data concerning the survivors of the nuclear explosions at Hiroshima and Nagasaki. Crucial to determining these guidelines is the radiation from the explosions. We have measured gamma-ray pulse-height distributions from an accurate replica of the Little Boy device used at Hiroshima, operated at low power levels near critical. The device was placed outdoors on a stand 4 m from the ground to minimize environmental effects. The power levels were based on a monitor detector calibrated very carefully in independent experiments. High-resolution pulse-height distributions were acquired with a germanium detector to identify the lines and to obtain line intensities. The 7631 to 7645 keV doublet from neutron capture in the heavy steel case was dominant. Low-resolution pulse-height distributions were acquired with bismuth-germanate detectors. We calculated flux spectra from these distributions using accurately measured detector response functions and efficiency curves. We then calculated dose-rate spectra from the flux spectra using a flux-to-dose-rate conversion procedure. The integral of each dose-rate spectrum gave an integral dose rate. The integral doses at 2 m ranged from 0.46 to 1.03 mrem per 10/sup 13/ fissions. The output of the Little Boy replica can be calculated with Monte Carlo codes. Comparison of our experimental spectra, line intensities, and integral doses can be used to verify these calculations at low power levels and give increased confidence to the calculated values from the explosion at Hiroshima. These calculations then can be used to establish better radiation safety guidelines. 7 references, 7 figures, 2 tables.

Moss, C.E.; Lucas, M.C.; Tisinger, E.W.; Hamm, M.E.

1984-01-01T23:59:59.000Z

250

Rail Coal Transportation Rates  

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

reports reports Coal Transportation Rates to the Electric Power Sector With Data through 2010 | Release Date: November 16, 2012 | Next Release Date: December 2013 | Correction Previous editions Year: 2011 2004 Go Figure 1. Deliveries from major coal basins to electric power plants by rail, 2010 Background In this latest release of Coal Transportation Rates to the Electric Power Sector, the U.S. Energy Information Administration (EIA) significantly expands upon prior versions of this report with the incorporation of new EIA survey data. Figure 1. Percent of total U.S. rail shipments represented in data figure data Previously, EIA relied solely on data from the U.S. Surface Transportation Board (STB), specifically their confidential Carload Waybill Sample. While valuable, due to the statistical nature of the Waybill data,

251

Plant Tumor Growth Rates  

NLE Websites -- All DOE Office Websites (Extended Search)

Plant Tumor Growth Rates Plant Tumor Growth Rates Name: Gina and Maria Location: N/A Country: N/A Date: N/A Question: We are doing a science fair project on if B. Carotene, Green tea, and Grape Seed Extract helps plants against the crown gall disease. We injected sunflowers with agrobacterium tum. one week ago (Sun. Feb. 27, 2000). Our questions is how long will it take for the tumors to grow? We scratched the surface of the stems and injected the agrobacterium in the wound. Also which do you think, in your opinion, will do the best, if any? Our science fair is April 13, do you think we'll have growth before then, atleast enough time to do our conclusion and results? Thank you, any information you forward will be very helpful. Replies: Sunflowers form galls relatively quickly. I usually get them in two weeks at least. Good luck.

252

Adjusted Growth Rates*  

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

Jan. '99 to Feb. '99: -1.7% Feb. '98 to Feb. '99: +19.8% YTD '98 to YTD '99: +15.0% 4,100 4,400 4,700 5,000 5,300 5,600 5,900 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Millions of Gallons U.S. Distillate Fuel Sales 2011 2012 2013 Adjusted Growth Rates* Jul '13 to Aug '13: 2.5% Aug '12 to Aug '13: -1.3% YTD '12 to YTD '13: 1.5% 300 400 500 600 700 800 900 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Millions of Gallons U.S. Residual Fuel Sales 2011 2012 2013 Adjusted Growth Rates* Jul '13 to Aug '13: -0.8%

253

Low Dose Radiation Research Program: David J. Chen  

NLE Websites -- All DOE Office Websites (Extended Search)

2003 Workshop: Gene Expression Profile of Normal Human Fibroblast After Ionizing Irradiation, a comparison study between low dose and high dose. Chen, D.J. 2002 Workshop:...

254

Low Dose Radiation Research Program: Depletion of the Vertebrate...  

NLE Websites -- All DOE Office Websites (Extended Search)

Laboratory, Berkeley, California To better understand the responses to low dose ionizing radiation, we proposed in Aim 1 of our Low Dose grant to use dominant-negative...

255

Low Dose Radiation Research Program Website â?? Highlighting...  

NLE Websites -- All DOE Office Websites (Extended Search)

Website Highlighting Low Dose Research Bill Morgan Pacific Northwest National Laboratory Abstract The Low Dose Radiation Research Programs website is found at http:...

256

Low Dose Radiation Program: Links - General Radiation Information  

NLE Websites -- All DOE Office Websites (Extended Search)

General Radiation Information Answers to Questions about Radiation Dose Ranges Charts - tables showing radiation dose ranges from radio diagnostics to cancer radiotherapy....

257

Low Dose Radiation Research Program Website ? Highlighting Low...  

NLE Websites -- All DOE Office Websites (Extended Search)

Research Program Website - Highlighting Low Dose Research Bill Morgan, Principal Investigator; Julie Wiley, Website Content Manager; Christine Novak, Webmaster The Low Dose...

258

RADIATION DOSE ESTIMATES TO ADULTS AND CHILDREN FROM VARIOUS  

NLE Websites -- All DOE Office Websites (Extended Search)

RADIATION DOSE ESTIMATES TO ADULTS AND CHILDREN FROM VARIOUS RADIOPHARMACEUTICALS Latest Revision Date: 43096 Radiation Internal Dose Information Center Oak Ridge Institute for...

259

Latest Research, Response to Fukushima, Integrating Low Dose...  

NLE Websites -- All DOE Office Websites (Extended Search)

Latest Research, Response to Fukushima, Integrating Low Dose into Policy-All Featured at Annual Investigators' Workshop The 10th DOE Low Dose Radiation Research Program...

260

Low Dose Investigator one of Canada's Top 40  

NLE Websites -- All DOE Office Websites (Extended Search)

Low Dose Investigator one of Canada's Top 40 Olga Kovalchuk Congratulations to Low Dose Radiation Research Program investigator Olga Kovalchuk on being named one of "Canada's Top...

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261

Adjusted Growth Rates* Jan.  

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

Adjusted Adjusted Growth Rates* Jan. '99 to Feb. '99: -1.7% Feb. '98 to Feb. '99: +19.8% YTD '98 to YTD '99: +15.0% U.S. Distillate Fuel Sales 3,000 3,500 4,000 4,500 5,000 5,500 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Millions of Gallons 1998 1999 2000 Adjusted Growth Rates* Dec '99 to Jan '00: -7.4% Jan '99 to Jan '00: -0.1% YTD '99 to YTD '00: -0.1% U.S. Motor Gasoline Sales 8,000 9,000 10,000 11,000 12,000 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Millions of Gallons 1998 1999 2000 Adjusted Growth Rates* Dec '99 to Jan '00: -16.8% Jan '99 to Jan '00: -3.2% YTD '99 to YTD '00: -3.2% U.S. Kerosene-Type Jet Fuel Sales 1,500 1,600 1,700 1,800 1,900 2,000 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Millions of Gallons 1998 1999 2000 Adjusted Growth Rates* Dec '99 to Jan '00: -9.3% Jan '99 to Jan '00: +3.5% YTD '99 to YTD '00: +3.5% U.S. Propane Sales 600 800 1,000 1,200 1,400 1,600 1,800 Jan Feb Mar Apr May Jun Jul

262

Adjusted Growth Rates*  

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

Nov '99 to Dec '99: +5.3% Nov '99 to Dec '99: +5.3% Dec '98 to Dec '99: +8.7% YTD '98 to YTD '99: +5.0% U.S. Motor Gasoline Sales 8,000 9,000 10,000 11,000 12,000 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Millions of Gallons 1997 1998 1999 Adjusted Growth Rates* Nov '99 to Dec '99: +6.0% Dec '98 to Dec '99: +4.5% YTD '98 to YTD '99: +1.3% U.S. Kerosene-Type Jet Fuel Sales 1,500 1,600 1,700 1,800 1,900 2,000 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Millions of Gallons 1997 1998 1999 Adjusted Growth Rates* Nov '99 to Dec '99: +2.4% Dec '98 to Dec '99: +3.0% YTD '98 to YTD '99: +0.9% U.S. Propane Sales 600 800 1,000 1,200 1,400 1,600 1,800 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Millions of Gallons 1997 1998 1999 Adjusted Growth Rates* Nov '99 to Dec '99: +32.3% Dec '98 to Dec '99: +2.0% YTD '98 to YTD '99: +5.5%

263

Adjusted Growth Rates*  

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

July '99 to Aug. '99: +4.7% July '99 to Aug. '99: +4.7% Aug. '98 to Aug. '99: +1.3% YTD '98 to YTD '99: +4.7% U.S. Motor Gasoline Sales 8,000 9,000 10,000 11,000 12,000 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Millions of Gallons 1997 1998 1999 Adjusted Growth Rates* July '99 to Aug. '99: -1.9% Aug. '98 to Aug. '99: -0.4% YTD '98 to YTD '99: +0.9% U.S. Kerosene-Type Jet Fuel Sales 1,500 1,600 1,700 1,800 1,900 2,000 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Millions of Gallons 1997 1998 1999 Adjusted Growth Rates* July '99 to Aug. '99: -0.1% Aug. '98 to Aug. '99: -1.4% YTD '98 to YTD '99: -0.7% U.S. Propane Sales 600 800 1,000 1,200 1,400 1,600 1,800 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Millions of Gallons 1997 1998 1999 Adjusted Growth Rates* July '99 to Aug. '99: +22.3% Aug. '98 to Aug. '99: +21.1%

264

Adjusted Growth Rates*  

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

Aug '99 to Sep '99: +4.9% Aug '99 to Sep '99: +4.9% Sep '98 to Sep '99: +4.7% YTD '98 to YTD '99: +4.7% U.S. Motor Gasoline Sales 8,000 9,000 10,000 11,000 12,000 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Millions of Gallons 1997 1998 1999 Adjusted Growth Rates* Aug '99 to Sep '99: -2.4% Sep '98 to Sep '99: +0.4% YTD '98 to YTD '99: +1.3% U.S. Kerosene-Type Jet Fuel Sales 1,500 1,600 1,700 1,800 1,900 2,000 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Millions of Gallons 1997 1998 1999 Adjusted Growth Rates* Aug '99 to Sep '99: -2.1% Sep '98 to Sep '99: +4.6% YTD '98 to YTD '99: 0.0% U.S. Propane Sales 600 800 1,000 1,200 1,400 1,600 1,800 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Millions of Gallons 1997 1998 1999 Adjusted Growth Rates* Aug '99 to Sep '99: +7.3% Sep '98 to Sep '99: +8.4% YTD '98 to YTD '99: +8.3%

265

Adjusted Growth Rates*  

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

Oct '99 to Nov '99: +0.1% Oct '99 to Nov '99: +0.1% Nov '98 to Nov '99: +5.5% YTD '98 to YTD '99: +4.5% U.S. Motor Gasoline Sales 8,000 9,000 10,000 11,000 12,000 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Millions of Gallons 1997 1998 1999 Adjusted Growth Rates* Oct '99 to Nov '99: -0.7% Nov '98 to Nov '99: +1.7% YTD '98 to YTD '99: +1.1% U.S. Kerosene-Type Jet Fuel Sales 1,500 1,600 1,700 1,800 1,900 2,000 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Millions of Gallons 1997 1998 1999 Adjusted Growth Rates* Oct '99 to Nov '99: +2.5% Nov '98 to Nov '99: +6.0% YTD '98 to YTD '99: +0.8% U.S. Propane Sales 600 800 1,000 1,200 1,400 1,600 1,800 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Millions of Gallons 1997 1998 1999 Adjusted Growth Rates* Oct '99 to Nov '99: +9.7% Nov '98 to Nov '99: +2.2% YTD '98 to YTD '99: +6.2%

266

Adjusted Growth Rates*  

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

June '99 to July '99: -5.4% June '99 to July '99: -5.4% July '98 to July '99: +3.3% YTD '98 to YTD '99: +6.3% U.S. Motor Gasoline Sales 8,000 9,000 10,000 11,000 12,000 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Millions of Gallons 1997 1998 1999 Adjusted Growth Rates* June '99 to July '99: -0.5% July '98 to July '99: -0.4% YTD '98 to YTD '99: +1.1% U.S. Kerosene-Type Jet Fuel Sales 1,500 1,600 1,700 1,800 1,900 2,000 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Millions of Gallons 1997 1998 1999 Adjusted Growth Rates* June '99 to July '99: +0.5% July '98 to July '99: +1.0% YTD '98 to YTD '99: -0.3% U.S. Propane Sales 600 800 1,000 1,200 1,400 1,600 1,800 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Millions of Gallons 1997 1998 1999 Adjusted Growth Rates* June '99 to July '99: +1.5% July '98 to July '99: +10.2% YTD '98 to YTD '99: +7.2%

267

Adjusted Growth Rates*  

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

Sep '99 to Oct '99: +3.9% Sep '99 to Oct '99: +3.9% Oct '98 to Oct '99: +2.3% YTD '98 to YTD '99: +4.4% U.S. Motor Gasoline Sales 8,000 9,000 10,000 11,000 12,000 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Millions of Gallons 1997 1998 1999 Adjusted Growth Rates* Sep '99 to Oct '99: -0.2% Oct '98 to Oct '99: -0.9% YTD '98 to YTD '99: +1.0% U.S. Kerosene-Type Jet Fuel Sales 1,500 1,600 1,700 1,800 1,900 2,000 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Millions of Gallons 1997 1998 1999 Adjusted Growth Rates* Sep '99 to Oct '99: -1.9% Oct '98 to Oct '99: -0.7% YTD '98 to YTD '99: +0.4% U.S. Propane Sales 600 800 1,000 1,200 1,400 1,600 1,800 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Millions of Gallons 1997 1998 1999 Adjusted Growth Rates* Sep '99 to Oct '99: -2.1% Oct '98 to Oct '99: -6.4% YTD '98 to YTD '99: +6.6%

268

Low Dose Radiation Research Program: Research Institutions  

NLE Websites -- All DOE Office Websites (Extended Search)

Institutions Institutions Lovelace Respiratory Research Institute Biological Bases for Radiation Adaptive Responses in the Lung-Lovelace Respiratory Research Institute, Albuquerque, NM USA Contact: Dr. Bobby R. Scott Program Objective Our research focuses on elucidating the biological bases for radiation adaptive responses in the lung and for suppressing lung cancer, and to use the knowledge gained to produce an improved systems-biology-based, risk model for lung cancer induction by low-dose, low linear-energy-transfer (LET) radiation. Research was initiated in October 2009. This research should help foster a new era of low-dose radiation risk/benefit assessment. It will have important implications for possible use of low-dose diagnostic radiation (e.g., X-rays) in cancer therapy. It

269

Radiotherapy Dose Fractionation under Parameter Uncertainty  

SciTech Connect

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.

Davison, Matt [Department of Applied Mathematics, University of Western Ontario, London, Ontario (Canada); Department of Statistical and Actuarial Science, University of Western Ontario, London, Ontario (Canada); Ivey School of Business, University of Western Ontario, London, Ontario (Canada); Kim, Daero [Department of Applied Mathematics, University of Western Ontario, London, Ontario (Canada); Keller, Harald [Department Radiation Oncology, University of Toronto, Toronto, Ontario (Canada); Radiation Medicine Program, Princess Margaret Hospital, Toronto, Ontario (Canada)

2011-11-30T23:59:59.000Z

270

Rate Adjustments and Public Involvement  

NLE Websites -- All DOE Office Websites (Extended Search)

Rate Adjustments and Public Involvement Documents Rate Adjustments and Public Involvement Documents CRSP Transmission 9/16/2013 WAPA-161 FRN, CRSP transmission and ancillary services rates extension Letter announcing two-year extension to CRSP transmission and ancillary services rates Letter announcing revised CRSP transmission rates for FY 2014 Accompanying calculation table for FY 2014 CRSP transmission rate letter Letter announcing revised CRSP transmission rates for FY 2013 Letter announcing revised CRSP transmission rates for FY 2012 Letter announcing revised CRSP transmission rates for FY 2011 Letter announcing revised CRSP transmission rates for FY 2010 SLCA/IP 9/16/2013 WAPA-161 FRN, SLCA/IP firm power rate extension Letter announcing two-year extension to SLCA/IP firm power rate SLCA/IP Tentative Rate Adjustment Schedule

271

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

Science Conference Proceedings (OSTI)

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 (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.

Galloway, Thomas J. [Department of Radiation Oncology, University of Florida College of Medicine, Gainesville, FL (United States); University of Florida Proton Therapy Institute, Jacksonville, FL (United States); Indelicato, Daniel J., E-mail: dindelicato@floridaproton.org [University of Florida Proton Therapy Institute, Jacksonville, FL (United States); Amdur, Robert J.; Morris, Christopher G.; Swanson, Erika L. [Department of Radiation Oncology, University of Florida College of Medicine, Gainesville, FL (United States); Marcus, Robert B. [University of Florida Proton Therapy Institute, Jacksonville, FL (United States)

2012-01-01T23:59:59.000Z

272

Low-dose computed tomography image restoration using previous normal-dose scan  

Science Conference Proceedings (OSTI)

Purpose: In current computed tomography (CT) examinations, the associated x-ray radiation dose is of a significant concern to patients and operators. A simple and cost-effective means to perform the examinations is to lower the milliampere-seconds (mAs) or kVp parameter (or delivering less x-ray energy to the body) as low as reasonably achievable in data acquisition. However, lowering the mAs parameter will unavoidably increase data noise and the noise would propagate into the CT image if no adequate noise control is applied during image reconstruction. Since a normal-dose high diagnostic CT image scanned previously may be available in some clinical applications, such as CT perfusion imaging and CT angiography (CTA), this paper presents an innovative way to utilize the normal-dose scan as a priori information to induce signal restoration of the current low-dose CT image series. Methods: Unlike conventional local operations on neighboring image voxels, nonlocal means (NLM) algorithm utilizes the redundancy of information across the whole image. This paper adapts the NLM to utilize the redundancy of information in the previous normal-dose scan and further exploits ways to optimize the nonlocal weights for low-dose image restoration in the NLM framework. The resulting algorithm is called the previous normal-dose scan induced nonlocal means (ndiNLM). Because of the optimized nature of nonlocal weights calculation, the ndiNLM algorithm does not depend heavily on image registration between the current low-dose and the previous normal-dose CT scans. Furthermore, the smoothing parameter involved in the ndiNLM algorithm can be adaptively estimated based on the image noise relationship between the current low-dose and the previous normal-dose scanning protocols. Results: Qualitative and quantitative evaluations were carried out on a physical phantom as well as clinical abdominal and brain perfusion CT scans in terms of accuracy and resolution properties. The gain by the use of the previous normal-dose scan via the presented ndiNLM algorithm is noticeable as compared to a similar approach without using the previous normal-dose scan. Conclusions: For low-dose CT image restoration, the presented ndiNLM method is robust in preserving the spatial resolution and identifying the low-contrast structure. The authors can draw the conclusion that the presented ndiNLM algorithm may be useful for some clinical applications such as in perfusion imaging, radiotherapy, tumor surveillance, etc.

Ma, Jianhua; Huang, Jing; Feng, Qianjin; Zhang, Hua; Lu, Hongbing; Liang, Zhengrong; Chen, Wufan [Department of Biomedical Engineering, Southern Medical University, Guangzhou, Guangdong 510515, China and Department of Radiology, State University of New York, Stony Brook, New York 11794 (United States); Department of Biomedical Engineering, Southern Medical University, Guangzhou, Guangdong 510515 (China); Department of Biomedical Engineering, Fourth Military Medical University, Xi'An, Shanxi 710032 (China); Department of Radiology, State University of New York, Stony Brook, New York 11794 (United States); Department of Biomedical Engineering, Southern Medical University, Guangzhou, Guangdong 510515 (China)

2011-10-15T23:59:59.000Z

273

Efficient and reliable 3D dose quality assurance for IMRT by combining independent dose calculations with measurements  

SciTech Connect

Purpose: Advanced radiotherapy treatments require appropriate quality assurance (QA) to verify 3D dose distributions. Moreover, increase in patient numbers demand efficient QA-methods. In this study, a time efficient method that combines model-based QA and measurement-based QA was developed; i.e., the hybrid-QA. The purpose of this study was to determine the reliability of the model-based QA and to evaluate time efficiency of the hybrid-QA method. Methods: Accuracy of the model-based QA was determined by comparison of COMPASS calculated dose with Monte Carlo calculations for heterogeneous media. In total, 330 intensity modulated radiation therapy (IMRT) treatment plans were evaluated based on the mean gamma index (GI) with criteria of 3%/3mm and classification of PASS (GI {<=} 0.4), EVAL (0.4 < GI > 0.6), and FAIL (GI {>=} 0.6). Agreement between model-based QA and measurement-based QA was determined for 48 treatment plans, and linac stability was verified for 15 months. Finally, time efficiency improvement of the hybrid-QA was quantified for four representative treatment plans. Results: COMPASS calculated dose was in agreement with Monte Carlo dose, with a maximum error of 3.2% in heterogeneous media with high density (2.4 g/cm{sup 3}). Hybrid-QA results for IMRT treatment plans showed an excellent PASS rate of 98% for all cases. Model-based QA was in agreement with measurement-based QA, as shown by a minimal difference in GI of 0.03 {+-} 0.08. Linac stability was high with an average GI of 0.28 {+-} 0.04. The hybrid-QA method resulted in a time efficiency improvement of 15 min per treatment plan QA compared to measurement-based QA. Conclusions: The hybrid-QA method is adequate for efficient and accurate 3D dose verification. It combines time efficiency of model-based QA with reliability of measurement-based QA and is suitable for implementation within any radiotherapy department.

Visser, R. [Department of Radiation Oncology, University of Groningen, University Medical Center Groningen, Groningen 9700 RB (Netherlands); Hanze University of Applied Sciences, Groningen 9714 CE (Netherlands); Wauben, D. J. L.; Godart, J.; Langendijk, J. A.; Veld, A. A. van't; Korevaar, E. W. [Department of Radiation Oncology, University of Groningen, University Medical Center Groningen, Groningen 9700 RB (Netherlands); Groot, M. de [Hanze University of Applied Sciences, Groningen 9714 CE (Netherlands)

2013-02-15T23:59:59.000Z

274

Inhalation and Ingestion Intakes with Associated Dose Estimates for Level II and Level III Personnel Using Capstone Study Data  

SciTech Connect

Depleted uranium (DU) intake rates and subsequent dose rates were estimated for personnel entering armored combat vehicles perforated with DU penetrators (level II and level III personnel) using data generated during the Capstone Depleted Uranium (DU) Aerosol Study. Inhalation intake rates and associated dose rates were estimated from cascade impactors worn by sample recovery personnel and from cascade impactors that served as area monitors. Ingestion intake rates and associated dose rates were estimated from cotton gloves worn by sample recovery personnel and from wipe test samples from the interior of vehicles perforated with large caliber DU munitions. The mean DU inhalation intake rate for level II personnel ranged from 0.447 mg h-1 based on breathing zone monitor data (in and around a perforated vehicle) to 14.5 mg h-1 based on area monitor data (in a perforated vehicle). The mean DU ingestion intake rate for level II ranged from 4.8 mg h-1 to 38.9 mg h-1 based on the wipe test data including surface to glove transfer factors derived from the Capstone data. Based on glove contamination data, the mean DU ingestion intake rates for level II and level III personnel were 10.6 mg h-1 was and 1.78 mg h-1, respectively. Effective dose rates and peak kidney uranium concentration rates were calculated based on the intake rates. The peak kidney uranium concentration rate cannot be multiplied by the total exposure duration when multiple intakes occur because uranium will clear from the kidney between the exposures.

Szrom, Fran; Falo, Gerald A.; Lodde, Gordon M.; Parkhurst, MaryAnn; Daxon, Eric G.

2009-03-01T23:59:59.000Z

275

PULSE RATE DIVIDER  

DOE Patents (OSTI)

A compact pulse-rate divider circuit affording low impedance output and high input pulse repetition rates is described. The circuit features a single secondary emission tube having a capacitor interposed between its dynode and its control grid. An output pulse is produced at the anode of the tube each time an incoming pulse at the control grid drives the tube above cutoff and the duration of each output pulse corresponds to the charging time of the capacitor. Pulses incoming during the time the grid bias established by the discharging capacitor is sufficiently negative that the pulses are unable to drive the tube above cutoff do not produce output pulses at the anode; these pulses are lost and a dividing action is thus produced by the circuit. The time constant of the discharge path may be vanied to vary in turn the division ratio of the circuit; the time constant of the charging circuit may be varied to vary the width of the output pulses. (AEC)

McDonald, H.C. Jr.

1962-12-18T23:59:59.000Z

276

Low Dose Radiation Cancer Risks: Epidemiological and Toxicological Models  

Science Conference Proceedings (OSTI)

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.

David G. Hoel, PhD

2012-04-19T23:59:59.000Z

277

Survey of innovative rates, 1991  

SciTech Connect

Current innovative rate data from 135 major utilities throughout the United States were gathered and analyzed. Over 1000 innovative rates that were in use by the utilities in 1990 and 1991 were identified, abstracted and entered into a database. Survey results indicate that over 616 million MWh were sold to the nearly five million customers using the innovative rates offered. From an annual sales perspective, the most widely used rates are demand-side management rates -- rates intended to change customer energy use -- and rates that are market-driven.'' The survey identified 525 demand-side management rates serving our four million customers with reported sales of approximately 520 million MWh. These rates serve over 80% of the total innovative rate customers and account for 84% of the total MWh sales. Also important in terms of MWh sales they represent are market-driven rates, which accounted for sales of 48 million MWh in 1990. Both demand-side management and market-driven rates show a 20% customer growth rate between 1988 and 1990. Other innovative rates examined in the survey included: prepaid service; load retention incentive rates; technology specific rates; and those rates related expressly to non-utility generators -- namely buy-back and standby rates.

White, L.J.; Wakefield, R.A.; McVicker, C.M.

1992-04-01T23:59:59.000Z

278

Survey of innovative rates, 1991  

Science Conference Proceedings (OSTI)

Current innovative rate data from 135 major utilities throughout the United States were gathered and analyzed. Over 1000 innovative rates that were in use by the utilities in 1990 and 1991 were identified, abstracted and entered into a database. Survey results indicate that over 616 million MWh were sold to the nearly five million customers using the innovative rates offered. From an annual sales perspective, the most widely used rates are demand-side management rates -- rates intended to change customer energy use -- and rates that are market-driven.'' The survey identified 525 demand-side management rates serving our four million customers with reported sales of approximately 520 million MWh. These rates serve over 80% of the total innovative rate customers and account for 84% of the total MWh sales. Also important in terms of the MWh sales they represent are market-driven rates, which accounted for sales of 48 million MWh in 1990. Both demand-side management and market-driven rates show a 20% customer growth rate between 1988 and 1990. Other innovative rates examined in the survey included: prepaid service; load retention incentive rates; technology specific rates; and those rates related expressly to non-utility generators -- namely buy-back and standby rates.

White, L.J.; Wakefield, R.A.; McVicker, C.M.

1992-04-01T23:59:59.000Z

279

Analytical models for total dose ionization effects in MOS devices.  

DOE Green Energy (OSTI)

MOS devices are susceptible to damage by ionizing radiation due to charge buildup in gate, field and SOI buried oxides. Under positive bias holes created in the gate oxide will transport to the Si / SiO{sub 2} interface creating oxide-trapped charge. As a result of hole transport and trapping, hydrogen is liberated in the oxide which can create interface-trapped charge. The trapped charge will affect the threshold voltage and degrade the channel mobility. Neutralization of oxidetrapped charge by electron tunneling from the silicon and by thermal emission can take place over long periods of time. Neutralization of interface-trapped charge is not observed at room temperature. Analytical models are developed that account for the principal effects of total dose in MOS devices under different gate bias. The intent is to obtain closed-form solutions that can be used in circuit simulation. Expressions are derived for the aging effects of very low dose rate radiation over long time periods.

Campbell, Phillip Montgomery; Bogdan, Carolyn W.

2008-08-01T23:59:59.000Z

280

Analysis of Dose Response for Circulatory Disease After Radiotherapy for Benign Disease  

SciTech Connect

Purpose: To assess the shape of the dose-response for various circulatory disease endpoints, and modifiers by age and time since exposure. Methods and Materials: This was an analysis of the US peptic ulcer data testing for heterogeneity of radiogenic risk by circulatory disease endpoint (ischemic heart, cerebrovascular, other circulatory disease). Results: There were significant excess risks for all circulatory disease, with an excess relative risk Gy{sup -1} of 0.082 (95% CI 0.031-0.140), and ischemic heart disease, with an excess relative risk Gy{sup -1} of 0.102 (95% CI 0.039-0.174) (both p = 0.01), and indications of excess risk for stroke. There were no statistically significant (p > 0.2) differences between risks by endpoint, and few indications of curvature in the dose-response. There were significant (p < 0.001) modifications of relative risk by time since exposure, the magnitude of which did not vary between endpoints (p > 0.2). Risk modifications were similar if analysis was restricted to patients receiving radiation, although the relative risks were slightly larger and the risk of stroke failed to be significant. The slopes of the dose-response were generally consistent with those observed in the Japanese atomic bomb survivors and in occupationally and medically exposed groups. Conclusions: There were excess risks for a variety of circulatory diseases in this dataset, with significant modification of risk by time since exposure. The consistency of the dose-response slopes with those observed in radiotherapeutically treated groups at much higher dose, as well as in lower dose-exposed cohorts such as the Japanese atomic bomb survivors and nuclear workers, implies that there may be little sparing effect of fractionation of dose or low-dose-rate exposure.

Little, Mark P., E-mail: mark.little@nih.gov [Radiation Epidemiology Branch, National Cancer Institute, Executive Plaza South, Rockville, Maryland (United States); Kleinerman, Ruth A. [Radiation Epidemiology Branch, National Cancer Institute, Executive Plaza South, Rockville, Maryland (United States)] [Radiation Epidemiology Branch, National Cancer Institute, Executive Plaza South, Rockville, Maryland (United States); Stovall, Marilyn; Smith, Susan A. [Department of Radiation Physics, University of Texas MD Anderson Cancer Center, Houston, Texas (United States)] [Department of Radiation Physics, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Mabuchi, Kiyohiko [Radiation Epidemiology Branch, National Cancer Institute, Executive Plaza South, Rockville, Maryland (United States)] [Radiation Epidemiology Branch, National Cancer Institute, Executive Plaza South, Rockville, Maryland (United States)

2012-12-01T23:59:59.000Z

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We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


281

Low Dose Radiation Research Program: Robert L. Ullrich  

NLE Websites -- All DOE Office Websites (Extended Search)

Robert L. Ullrich Robert L. Ullrich Colorado State University Currently Funded Projects Radiation Leukemogenesis at Low Dose Rates (NSCOR) Genetic Mechanisms of Induced Chromosomal Instability and their Relationships with Radiation Tumorigenesis Technical Abstracts 2006 Workshop: The Role of Telomere Dysfunction in Driving Genomic Instability Bailey, S.M., Williams, E.S., and Ullrich, R.L. 2005 Workshop: Dsyfunctional Mammalian Telomeres in DNA-PKcs Deficient Backgrounds Bailey, S.M., Williams, E., Hagelstrom, T., and Ullrich, R.L. 2003 Workshop: Dysfunctional Mammalian Telomeres Join to Double-Strand Breaks Bailey, S.M., Goodwin, E.H., Williams, E., and Ullrich, R.L. 2002 Workshop: Dysfunctional Telomeres, Radiation-Induced Instability and Tumorigenesis Bailey, S.M., Goodwin, E.H., Cornforth, M.N., and Ullrich, R.L.

282

Medical x-ray exposure doses as contaminants of atomic bomb doses  

SciTech Connect

Since 1967 at the times of their biennial ABCC/RERF radiological examinations, all Adult Health Study (AHS) subjects have been interviewed to determine the exposures to medical x-rays they experienced in institutions other than RERF in order to estimate the numbers of examinations and corresponding doses which they received. These data have been stored on computer tapes together with the doses these subjects received during their radiological examinations in the ABCC/RERF Department of Radiology. Thus, their medical x-ray doses are available along with their atomic bomb doses (tentative 1965 doses revised, T65DR) for assessment of the role of ionizing radiation in the development of diseases. The medical x-ray doses incurred at RERF were assessed by means of phantom dosimetry. Those at other institutions were determined using phantom dosimetry data and results of surveys for trends in radiological examinations in Hiroshima and Nagasaki. By the end of 1982, the average medical x-ray doses to the active bone marrow were 12.04 mGy for A-bomb exposed groups and 8.92 mGy for control groups (not-in-cities); to the male gonads, 2.26 mGy and 1.89 mGy, respectively; and to the female gonads, 17.45 mGy and 12.58 mGy, respectively. Results for Hiroshima and Nagasaki were similar. The main impact of medical x-ray doses was in the lowest T65DR group. Medical x-ray active bone marrow doses ranged from 0.05-500% (mean, 35%) of A-bomb doses in the 10-99 mGy T65DR group. In the 100-999 mGy T65DR group, medical x-ray active bone marrow doses ranged from 0.005-50% (mean, 5%) of their T65DR. In the greater than 1000-mGy T65DR group, medical x-ray exposures were proportionally less. Medical x-ray exposures produced smaller doses to the gonads of males than to those of the females.

Yamamoto, O.; Antoku, S.; Russell, W.J.; Fujita, S.; Sawada, S.

1988-03-01T23:59:59.000Z

283

Fluence-to-dose confusion regarding external stochastic dose determination within the DOE complex.  

SciTech Connect

The Department of Energy's (DOE) occupational radiation protection dose limits are specified in 10 CFR 835 (hereafter referred to as 'regulation'). Ambiguity in the regulation regarding designation of dose and fluence-to-dose conversion factors leads to confusion and disagreement regarding the appropriate choice of conversion factors. Three primary dose quantities of relevance are absorbed dose, D, quality factor, Q, and the product of those, called dose equivalent, H. The modifier Q is intended to express the long-term fatal cancer causing potential of different radiation types and generally increases with energy for neutrons. For photons, Q is close to unity regardless of energy. In principle, H could be estimated by incorporating a phantom and relevant Q values in a radiation-transport model. In practice, this would entail too much model complexity and computer time. The evaluator of H instead relies on pre-calculated energy-dependent fluence-to-dose conversion factors. Three primary sets of fluence-to-dose conversion factors are commonly used to determine stochastic dose for neutrons and photons: (1) ANSI/ANS-6.1.1-1977 that incorporates the NCRP-38 data for neutrons and sets based on Claiborne and Wells for photons, (2) ANSI/ANS -6.1.1-1991 that are based on and nearly identical to the neutron and photon sets in ICRP -51, and (3) neutron and photon sets in ICRP-74. The first set is maximum H values in a 30-cm diameter cylinder phantom for neutrons and in a 30-cm thick slab phantom for photons. The second set is effective dose equivalent, HE, derived from an anthropomorphic phantom by summing the products of tissue dose equivalents, HT, and tissue weighting factors, w{sub T}. The third set is effective dose, E, also derived from an anthropomorphic phantom by summing the products of H{sub T} and w{sub T}. E is functionally identical to H{sub E} except H{sub T} is the product of D and the radiation weighting factor, w{sub R}, which is similar in meaning to Q.

Shores, E. F. (Erik F.); Brown, T. H. (Thomas H.)

2002-01-01T23:59:59.000Z

284

Individual Dose Calculations with Use of the Revised Techa River Dosimetry System TRDS-2009D  

SciTech Connect

An updated deterministic version of the Techa River Dosimetry System (TRDS-2009D) has been developed to estimate individual doses from external exposure and intake of radionuclides for residents living on the Techa River contaminated as a result of radioactive releases from the Mayak plutonium facility in 1949–1956. The TRDS-2009D is designed as a flexible system that uses, depending on the input data for an individual, various elements of system databases to provide the dosimetric variables requested by the user. Several phases are included in the computation schedule. The first phase includes calculations with use of a common protocol for all cohort members based on village-average-intake functions and external dose rates; individual data on age, gender and history of residence are included in the first phase. This phase results in dose estimates similar to those obtained with system TRDS-2000 used previously to derive risks of health effects in the Techa River Cohort. The second phase includes refinement of individual internal doses for those persons who have had body-burden measurements or exposure parameters specific to the household where he/she lived on the Techa River. The third phase includes summation of individual doses from environmental exposure and from radiological examinations. The results of TRDS-2009D dose calculations have demonstrated for the ETRC members on average a moderate increase in RBM dose estimates (34%) and a minor increase (5%) in estimates of stomach dose. The calculations for the members of the ETROC indicated similar small changes for stomach, but significant increase in RBM doses (400%). Individual-dose assessments performed with use of TRDS-2009D have been provided to epidemiologists for exploratory risk analysis in the ETRC and ETROC. These data provide an opportunity to evaluate the possible impact on radiogenic risk of such factors as confounding exposure (environmental and medical), changes in the Techa River source-term data and the change of the approach to individual internal dose estimation (90Sr-body burden measurements and family correlations vs. village averages). Our further plan is to upgrade the TRDS-2009D and to complete a stochastic version of the dosimetry system.

Degteva, M. O.; Shagina, N. B.; Tolstykh, E. I.; Vorobiova, M. I.; Anspaugh, L. R.; Napier, Bruce A.

2009-10-23T23:59:59.000Z

285

Low Dose Radiation Research Program: Effects of Low Doses of Radiation on  

NLE Websites -- All DOE Office Websites (Extended Search)

Low Doses of Radiation on DNA Repair Low Doses of Radiation on DNA Repair Eric Ackerman Pacific Northwest National Laboratory Why this Project? Even low doses (0.1 Gy) exert measurable effects on DNA repair. The first-known oxidative lesion repaired only by nucleotide excision repair found in normal cells is cyclo-dA. This lesion is found in normal cells and thought to be a byproduct of oxidative metabolism. When this lesion occurs, it stimulates repair. If repair is stimulated by low dose radiation, there are some implications for human health. For example, do some individuals exhibit a greater, lower, or no stimulation to certain DNA lesions? If there are population polymorphism that influence DNA repair, then it would be possible to use our assay for screening individuals for repair sensitivity.

286

Low Dose Radiation Research Program: Effects of Low Doses of Radiation on  

NLE Websites -- All DOE Office Websites (Extended Search)

Abstract Abstract Title: Effects of Low Doses of Radiation on DNA Repair (PNNL Project # 42699) Authors: Eric J. Ackerman, Ph.D. Institutions: Pacific Northwest National Laboratory Richland, WA We developed a functional assay to measure the effects of LDR on repair of many different lesions representative of those found in cells as consequences of normal oxidative metabolism, as well as those caused by radiation. Currently only 1/10th attomole =105 damaged molecules/cell and 3000 cells/measurement are required. We have found that even low doses (10 rad) exert measurable effects on DNA repair. Interestingly, the amount of DNA repair increases at 10-50 rads, plateaus, and then increases even further at higher doses well below doses where radiation-induced lethality

287

Low Dose Radiation Research Program: Low Dose Response of Respiratory Cells  

NLE Websites -- All DOE Office Websites (Extended Search)

Low Dose Radiation Research Program: Low Dose Response of Respiratory Low Dose Radiation Research Program: Low Dose Response of Respiratory Cells in Intact Tissues and Reconstituted Tissue Constructs Authors: John Ford, Amy Maslowski, Alex Redd and Les Braby Institutions: Texas A&M University, College Station, TX We are developing a model of respiratory tissue using a perfusion culture system. We are using this system to quantify the effects of normal tissue architecture, and the interaction of epithelial cells with other cell types, on radiation-induced bystander effects. Tracheal tissue taken from young adult Fischer 344 rats is imbedded in a growth factor enriched agarose matrix. The chamber is designed to allow growth medium to periodically wash the epithelial surface of the tracheal lumen while maintaining the air-interface that is necessary for the normal

288

Low Dose Radiation Research Program: Studies of Low-Dose Bystander...  

NLE Websites -- All DOE Office Websites (Extended Search)

Low-Dose Bystander Effects Using a Focused Soft X-ray Microprobe Kevin M. Prise1, Melvyn Folkard1, Giuseppe Schettino1, Elena Rusyn2, Heidi C. Newman1, Kathryn D. Held2 and Barry...

289

Scoping calculation for components of the cow-milk dose pathway for evaluating the dose contribution from iodine-131. Hanford Environmental Dose Reconstruction Project: Dose code recovery activities  

Science Conference Proceedings (OSTI)

A series of scoping calculations have been undertaken to evaluate The absolute and relative contribution of different exposure pathways to doses that may have been received by individuals living in the vicinity of the Hanford site. This scoping calculation (Calculation 001) examined the contributions of the various exposure pathways associated with environmental transport and accumulation of iodine-131 in the pasture-cow-milk pathway. Addressed in this calculation were the contributions to thyroid dose of infants and adult from (1) the ingestion by dairy cattle of various feedstuffs (pasturage, silage, alfalfa hay, and grass hay) in four different feeding regimes; (2) ingestion of soil by dairy cattle; (3) ingestion of stared feed on which airborne iodine-131 had been deposited; and (4) inhalation of airborne iodine-131 by dairy cows.

Ikenberry, T.A.; Napier, B.A.

1992-12-01T23:59:59.000Z

290

Reconstruction of chronic dose equivalents for Rongelap and Utirik residents: 1954 to 1980  

Science Conference Proceedings (OSTI)

From June 1946 to August 1958, the US Department of Defense and Atomic Energy Commission conducted nuclear weapons tests in the Northern Marshall Islands. BRAVO, an aboveground test in the Castle series, resulted in radioactive fallout contaminating Rongelap and Utirik Atolls. On March 3, 1954, the inhabitants of these atolls were relocated until radiation exposure rates declined to acceptable levels. Environmental and personnel radiological monitoring programs were begun in the mid 1950's by Brookhaven National Laboratory to ensure that dose equivalents received or committed remained within US Federal Radiation Council Guidelines for members of the general public. Body burden and dose equivalent histories along with activity ingestion patterns post return are presented. Dosimetric methods, results, and internal dose equivalent distributions for subgroups of the population are also described.

Lessard, E.T.; Greenhouse, N.A.; Miltenberger, R.P.

1980-10-01T23:59:59.000Z

291

Scaffolding Program Management for Dose Reduction  

Science Conference Proceedings (OSTI)

The nuclear industry has reduced collective radiation exposure annually since 1990, with the exception of 2003. (Large component replacement in several plants caused most of the increase in 2003.) In order for the industry to meet and maintain their continuous improvement goals, it is necessary to carefully review the activities in which workers acquire dose. Research has shown that one of the primary contributors is the erection and disassembly of scaffolding.

2004-11-17T23:59:59.000Z

292

Dose Reduction Options for Refueling Tasks  

Science Conference Proceedings (OSTI)

Improved operational practices and successful deployment of several exposure reduction technologies have assisted the industry in meeting current regulatory limits. However, based on an analysis of industry collective and individual exposures, activities directly related to refueling continue to account for a significant, repetitive portion of the total fuel cycle exposure, and to individual exposure for many of the industry’s highest dose workers. This severely challenges the industry’s ...

2012-12-12T23:59:59.000Z

293

EPRI Integrated Dose Reduction Program Pilot Study  

Science Conference Proceedings (OSTI)

The Integrated Dose Reduction (IDR) project is an integral part of EPRI's support to nuclear plant radiation protection programs. The broad objective of the IDR program is to review existing and recent industry developments and provide utilities with an integrated plan for EPRI's assistance based on a plant's specific needs. This document describes a pilot test of this product at a host site, and identifies areas where EPRI's RP assessments and technical assistance can support key plant programs.

2003-11-21T23:59:59.000Z

294

electric rates | OpenEI  

Open Energy Info (EERE)

electric rates electric rates Dataset Summary Description This dataset, compiled by NREL and Ventyx, provides average residential, commercial and industrial electricity rates by zip code for both investor owned utilities (IOU) and non-investor owned utilities. Note: the file includes average rates for each utility, but not the detailed rate structure data found in the database available via the zip-code look-up feature on the OpenEI Utilities page (http://en.openei.org/wiki/Gateway:Utilities). The data was released by NREL/Ventyx in February 2011. Source NREL and Ventyx Date Released February 24th, 2012 (2 years ago) Date Updated Unknown Keywords electric rates rates US utilities Data text/csv icon IOU rates by zipcode (csv, 1.7 MiB) text/csv icon Non-IOU rates by zipcode (csv, 2.1 MiB)

295

Rate Schedules | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Rate Schedules 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 production and transmission costs, which include the amortization of the Federal investment allocated to power. Latest Rate Schedules October 1, 2012 ALA-1-N Wholesale Power Rate Schedule Area: PowerSouth Energy Cooperative System: Georgia-Alabama-South Carolina October 1, 2012

296

Failure rate data for fusion safety and risk assessment  

SciTech Connect

The Fusion Safety Program (FSP) at the Idaho National Engineering Laboratory (INEL) conducts safety research in materials, chemical reactions, safety analysis, risk assessment, and in component research and development to support existing magnetic fusion experiments and also to promote safety in the design of future experiments. One of the areas of safety research is applying probabilistic risk assessment (PRA) methods to fusion experiments. To apply PRA, we need a fusion-relevant radiological dose code and a component failure rate data base. This paper describes the FSP effort to develop a failure rate data base for fusion-specific components.

Cadwallader, L.C.

1993-01-01T23:59:59.000Z

297

Failure rate data for fusion safety and risk assessment  

SciTech Connect

The Fusion Safety Program (FSP) at the Idaho National Engineering Laboratory (INEL) conducts safety research in materials, chemical reactions, safety analysis, risk assessment, and in component research and development to support existing magnetic fusion experiments and also to promote safety in the design of future experiments. One of the areas of safety research is applying probabilistic risk assessment (PRA) methods to fusion experiments. To apply PRA, we need a fusion-relevant radiological dose code and a component failure rate data base. This paper describes the FSP effort to develop a failure rate data base for fusion-specific components.

Cadwallader, L.C.

1993-04-01T23:59:59.000Z

298

National Utility Rate Database: Preprint  

DOE Green Energy (OSTI)

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.

Ong, S.; McKeel, R.

2012-08-01T23:59:59.000Z

299

Low Dose Radiation Program: Links - Organizations Conducting Radiation  

NLE Websites -- All DOE Office Websites (Extended Search)

Conducting Low Dose Radiation Research Conducting Low Dose Radiation Research DOE Low Dose Radiation Research Program DoReMi Integrating Low Dose Research High Level Expert Group (HLEG) on European Low Dose Risk Research Multidisciplinary European Low Dose Initiative (MELODI) RISC-RAD Radiosensitivity of Individuals and Susceptibility to Cancer induced by Ionizing Radiation United States Transuranium & Uranium Registries Organizations Conducting other Radiation Research Argonne National Laboratory (ANL) Armed Forces Radiology Research Institute (AFRRI) Atmospheric Radiation Measurement (ARM) Program Brookhaven National Laboratory (BNL) Center for Devices and Radiological Health (CDRH) Central Research Institute of Electric Power Industry (CRIEPI) Colorado State University Columbia University

300

Development of animation and simulation module for evaluation of Worker's dose  

SciTech Connect

A study to visualize the radioactivity distribution in a dismantling facility that was contaminated by the radiation from the exposure room at KRR 2(Korean Research Reactor TRIGA MARK III) was carried out to improve worker safety and decommissioning productivity. As a basic study to minimize a radiation exposure, the worker exposure dose was calculated using the MCNP-4C (Monte Carlo N-Particle-4C). Secondly, an animation and simulation module was implemented to simulate a worker's real-time dose. The results show that various kinds of dismantling activities can be simulated while simultaneously viewing the exposure dose in a real-time according to the selected scenario for the animation. Current work is focus on exploring the evaluation of a worker's dose in a virtual dismantling area by using computer graphics. Future work will seek an optimization of the major parameters that directly affect a personnel exposure dose rate. This will enable a worker who is engaged in a hazardous area to attain an improve safety by decreasing exposure when applied as a useful tool to dismantle nuclear facilities. (authors)

Park, H.S.; Kim, G.H.; Lee, K.W.; Jung, C.H. [Korea Atomic Energy Research Institute, Yuseong-gu, Daejeon (Korea, Republic of); Jin, S.I. [Chungnam National Univ., Dept. of Computer Science, Yuseong-gu, Daejeon (Korea, Republic of)

2007-07-01T23:59:59.000Z

Note: This page contains sample records for the topic "beta-gamma dose rates" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


301

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

SciTech Connect

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.

Azzam, Edouard I

2013-01-16T23:59:59.000Z

302

Custom Device for Low-Dose Gamma Irradiation of Biological Samples  

E-Print Network (OSTI)

When astronauts travel in space, their primary health hazards are high-energy cosmic radiations from galactic cosmic rays (GCR). Most galactic cosmic rays have energies between 100 MeV and 10 GeV. For occupants inside of a space shuttle, the structural material is efficient to absorb most of the cosmic-ray energy and reduce the interior dose rate to below 1.2 mGy per day. However, the biological effects of prolonged exposure to low-dose radiation are not well understood. The purpose of this research was to examine the feasibility of constructing a low-dose irradiation facility to simulate the uniform radiation field that exists in space. In this research, we used a pre-manufactured incubator, specifically the Thermo Scientific Forma Series II Water Jacketed CO2 Incubator, to act as shielding and simulate the exterior of the space shuttle. To achieve the desired dose rate (< 1 mGy/h) inside the incubator volume, the computer code MCNPX was used to determine required source activity and distance between the shielding and source. Once the activity and distance were calculated, an experiment was carried out to confirm the simulation results. The confirmation used survey meters and thermoluminescence dosimeters (TLDs) to map the radiation field within the incubator.

Bi, Ruoming

2011-12-01T23:59:59.000Z

303

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

Science Conference Proceedings (OSTI)

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.

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

1981-04-01T23:59:59.000Z

304

DOE Guidance-Category Rating  

Energy.gov (U.S. Department of Energy (DOE))

This memorandum is to establish the Department of Energy's (DOE's) policy for the use of Category Rating.

305

ARCS – Access Rate Control System  

protected steel housing. ... Access Rate Control System This rugged, maintenance- ... Y-12 is seeking an industry partner to fully com-

306

Patient radiation dose in prospectively gated axial CT coronary angiography and retrospectively gated helical technique with a 320-detector row CT scanner  

Science Conference Proceedings (OSTI)

Purpose: The aim of this study was to evaluate radiation dose to patients undergoing computed tomography coronary angiography (CTCA) for prospectively gated axial (PGA) technique and retrospectively gated helical (RGH) technique. Methods: Radiation doses were measured for a 320-detector row CT scanner (Toshiba Aquilion ONE) using small sized silicon-photodiode dosimeters, which were implanted at various tissue and organ positions within an anthropomorphic phantom for a standard Japanese adult male. Output signals from photodiode dosimeters were read out on a personal computer, from which organ and effective doses were computed according to guidelines published in the International Commission on Radiological Protection Publication 103. Results: Organs that received high doses were breast, followed by lung, esophagus, and liver. Breast doses obtained with PGA technique and a phase window width of 16% at a simulated heart rate of 60 beats per minute were 13 mGy compared to 53 mGy with RGH technique using electrocardiographically dependent dose modulation at the same phase window width as that in PGA technique. Effective doses obtained in this case were 4.7 and 20 mSv for the PGA and RGH techniques, respectively. Conversion factors of dose length product to the effective dose in PGA and RGH were 0.022 and 0.025 mSv mGy{sup -1} cm{sup -1} with a scan length of 140 mm. Conclusions: CTCA performed with PGA technique provided a substantial effective dose reduction, i.e., 70%-76%, compared to RGH technique using the dose modulation at the same phase windows as those in PGA technique. Though radiation doses in CTCA with RGH technique were the same level as, or some higher than, those in conventional coronary angiography (CCA), the use of PGA technique reduced organ and effective doses to levels less than CCA except for breast dose.

Seguchi, Shigenobu; Aoyama, Takahiko; Koyama, Shuji; Fujii, Keisuke; Yamauchi-Kawaura, Chiyo [Graduate School of Medicine, Nagoya University, Daikominami, Higashi-ku, Nagoya 461-8673 (Japan) and Department of Medical Technology, Nagoya Daini Red Cross Hospital, Myouken-chou, Showa-ku, Nagoya 466-8650 (Japan); Graduate School of Medicine, Nagoya University, Daikominami, Higashi-ku, Nagoya 461-8673 (Japan); Section of Radiological Protection, National Institute of Radiological Sciences, Anagawa, Inage-ku, Chiba 263-8555 (Japan); Graduate School of Medicine, Nagoya University, Daikominami, Higashi-ku, Nagoya 461-8673 (Japan)

2010-11-15T23:59:59.000Z

307

Investigation of tilted dose kernels for portal dose prediction in a-Si electronic portal imagers  

SciTech Connect

The effect of beam divergence on dose calculation via Monte Carlo generated dose kernels was investigated in an amorphous silicon electronic portal imaging device (EPID). The flat-panel detector was simulated in EGSnrc with an additional 3.0 cm water buildup. The model included details of the detector's imaging cassette and the front cover upstream of it. To approximate the effect of the EPID's rear housing, a 2.1 cm air gap and 1.0 cm water slab were introduced into the simulation as equivalent backscatter material. Dose kernels were generated with an incident pencil beam of monoenergetic photons of energy 0.1, 2, 6, and 18 MeV. The orientation of the incident pencil beam was varied from 0 deg. to 14 deg. in 2 deg. increments. Dose was scored in the phosphor layer of the detector in both cylindrical (at 0 deg. ) and Cartesian (at 0 deg. -14 deg.) geometries. To reduce statistical fluctuations in the Cartesian geometry simulations at large radial distances from the incident pencil beam, the voxels were first averaged bilaterally about the pencil beam and then combined into concentric square rings of voxels. Profiles of the EPID dose kernels displayed increasing asymmetry with increasing angle and energy. A comparison of the superposition (tilted kernels) and convolution (parallel kernels) dose calculation methods via the {chi}-comparison test (a derivative of the {gamma}-evaluation) in worst-case-scenario geometries demonstrated an agreement between the two methods within 0.0784 cm (one pixel width) distance-to-agreement and up to a 1.8% dose difference. More clinically typical field sizes and source-to-detector distances were also tested, yielding at most a 1.0% dose difference and the same distance-to-agreement. Therefore, the assumption of parallel dose kernels has less than a 1.8% dosimetric effect in extreme cases and less than a 1.0% dosimetric effect in most clinically relevant situations and should be suitable for most clinical dosimetric applications. The resulting time difference for the parallel kernel assumption versus the tilted kernels was 10.5 s vs 18 h (a factor of approximately 6000), dependent on existing hardware and software details.

Chytyk, K.; McCurdy, B. M. C. [Division of Medical Physics, CancerCare Manitoba, 675 McDermot Avenue, Winnipeg, Manitoba R3E 0V9, Canada and Department of Physics and Astronomy, University of Manitoba, Winnipeg, Manitoba R3T 2N2 (Canada); Division of Medical Physics, CancerCare Manitoba, 675 McDermot Avenue, Winnipeg, Manitoba R3E 0V9 (Canada); Department of Physics and Astronomy, University of Manitoba, Winnipeg, Manitoba R3T 2N2 (Canada) and Department of Radiology, University of Manitoba, Winnipeg, Manitoba R3A 1R9 (Canada)

2006-09-15T23:59:59.000Z

308

Analysis of low dose radiation induced epigenetic modifications...  

NLE Websites -- All DOE Office Websites (Extended Search)

levels ofbiological organization when organisms are exposed to low doses (<0.1Gy) of irradiation.Recent work in determining the exact effects of low dose radiation have shown that...

309

Latest Research, Effects from Low Dose Exposure, Response to...  

NLE Websites -- All DOE Office Websites (Extended Search)

Program Draft of Low Dose Program History 1998-2008 Available for Review and Comment The history of the first decade of DOE Low Dose Radiation Research Program has been written by...

310

Low Dose Radiation Research Program: Cytogenetic tests of Radiobiologi...  

NLE Websites -- All DOE Office Websites (Extended Search)

relevant low-dose range (less than 0.1 Gy). Relate chromosome damage to radiation-induced cancer. Research Approach By studying molecular mechanisms relevant to low doses and low...

311

Annual report shows potential INL radiation dose well below safe...  

NLE Websites -- All DOE Office Websites (Extended Search)

estimates that the dose from a chest X-ray is about 10 mrem and the dose from cosmic radiation during a 3 hour domestic airline flight is about 1 mrem. Operations at the...

312

Radiological Dose Assessment 8 2007 Site environmental report8-  

E-Print Network (OSTI)

to the absorbed radiation dose. The environmental TLDs used at the Lab- oratory are composed of calcium fluoride Approach for Evaluating Radiation Doses to Aquatic and Terrestrial Biota, provides the guidelines

Homes, Christopher C.

313

Preliminary dose assessment of the Chernobyl accident  

Science Conference Proceedings (OSTI)

From the major accident at Unit 4 of the Chernobyl nuclear power station, a plume of airborne radioactive fission products was initially carried northwesterly toward Poland, thence toward Scandinavia and into Central Europe. Reports of the levels of radioactivity in a variety of media and of external radiation levels were collected in the Department of Energy's Emergency Operations Center and compiled into a data bank. Portions of these and other data which were obtained directly from published and official reports were utilized to make a preliminary assessment of the extent and magnitude of the external dose to individuals downwind from Chernobyl. Radioactive /sup 131/I was the predominant fission product. The time of arrival of the plume and the maximum concentrations of /sup 131/I in air, vegetation and milk and the maximum reported depositions and external radiation levels have been tabulated country by country. A large amount of the total activity in the release was apparently carried to a significant elevation. The data suggest that in areas where rainfall occurred, deposition levels were from ten to one-hundred times those observed in nearby ''dry'' locations. Sufficient spectral data were obtained to establish average release fractions and to establish a reference spectra of the other nuclides in the release. Preliminary calculations indicated that the collective dose equivalent to the population in Scandinavia and Central Europe during the first year after the Chernobyl accident would be about 8 x 10/sup 6/ person-rem. From the Soviet report, it appears that a first year population dose of about 2 x 10/sup 7/ person-rem (2 x 10/sup 5/ Sv) will be received by the population who were downwind of Chernobyl within the U.S.S.R. during the accident and its subsequent releases over the following week. 32 refs., 14 figs., 20 tabs.

Hull, A.P.

1987-01-01T23:59:59.000Z

314

Remote Sensing Methods for Imaging Dose to Water  

Science Conference Proceedings (OSTI)

Remote Sensing Methods for Imaging Dose to Water. Summary: Calorimetry based upon remote sensing of the temperature ...

2013-02-26T23:59:59.000Z

315

Hanford Environmental Dose Reconstruction Project. Monthly report, November 1991  

SciTech Connect

The objective of the Hanford Environmental Dose Reconstruction 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; demographics, agriculture, food habits; environmental pathways and dose estimates.

Finch, S.M.; McMakin, A.H. [comps.

1991-12-31T23:59:59.000Z

316

Dose measurements and calculations in the epithermal neutron beam at the Brookhaven Medical Research Reactor (BMRR)  

SciTech Connect

The characteristics of the epithermal neutron beam at BMRR were measured, calculated, and reported. This beam has already been used for animal irradiations. We anticipate that it will be used for clinical trials. Thermal and epithermal neutron flux densities distributions, and dose rate distributions, as a function of depth were measured in a lucite dog-head phantom. Monte Carlo calculations were performed and compared with the measured values. 2 refs., 4 figs., 1 tab.

Fairchild, R.G.; Greenberg, D.; Kamen, Y.; Fiarman, S. (Brookhaven National Lab., Upton, NY (USA). Medical Dept.); Benary, V. (Brookhaven National Lab., Upton, NY (USA). Medical Dept. Tel Aviv Univ. (Israel)); Kalef-Ezra, J. (Brookhaven National Lab., Upton, NY (USA). Medical Dept. Ioannina Univ. (Greece)); Wielopolski, L. (Brookhaven National Lab., Upton, NY (USA). Medical Dept. State Univ. of New

1990-01-01T23:59:59.000Z

317

Functional Proteomic Pattern Identification under Low Dose Ionizing Radiation  

Science Conference Proceedings (OSTI)

The goal of this study is to explore and to understand the dynamic responses of signaling pathways to low dose ionizing radiation (IR). Low dose radiation (10 cGy or lower) affects several signaling pathways including DNA repair, survival, cell cycle, ... Keywords: low dose radiation, functional proteomics

Young Bun Kim; Jean Gao; Ying Dong; Chin-Rang Yang

2008-11-01T23:59:59.000Z

318

Asymptotic Cellular Growth Rate as the Effective Information Utilization Rate  

E-Print Network (OSTI)

We study the average asymptotic growth rate of cells in randomly fluctuating environments. Using a game-theoretic perspective, we show that any response strategy has an asymptotic growth rate, which is the sum of: (i) the maximal growth rate at the worst possible distribution of environments, (ii) relative information between the actual distribution of environments to the worst one, and (iii) information utilization rate which is the information rate of the sensory devices minus the "information dissipation rate", the amount of information not utilized by the cell for growth. In non-stationary environments, the optimal strategy is the time average of the instantaneous optimal strategy and the optimal switching times are evenly spaced in the statistical (Fisher) metric.

Pugatch, Rami; Tlusty, Tsvi

2013-01-01T23:59:59.000Z

319

Dose to man from a hypothetical loss-of-coolant accident at the Rancho Seco Nuclear Power Plant  

Science Conference Proceedings (OSTI)

At the request of the Sacramento Municipal Utilities District, we used our computer codes, MATHEW and ADPIC, to assess the environmental impact of a loss-of-coolant accident at the Rancho Seco Nuclear Power Plant, about 40 kilometres southeast of Sacramento, California. Meteorological input was selected so that the effluent released by the accident would be transported over the Sacramento metropolitan area. With the release rates provided by the Sacramento Municipal Utilities District, we calculated the largest total dose for a 24-hour release as 70 rem about one kilometre northwest of the reactor. The largest total dose in the Sacramento metropolitan area is 780 millirem. Both doses are from iodine-131, via the forage-cow-milk pathway to an infant's thyroid. The largest dose near the nuclear plant can be minimized by replacing contaminated milk and by giving the cows dry feed. To our knowledge, there are no milk cows within the Sacramento metropolitan area.

Peterson, K.R.; Greenly, G.D.

1981-02-01T23:59:59.000Z

320

2011 Heat Rate Improvement Conference  

Science Conference Proceedings (OSTI)

With the rising cost of fuel and the strong possibility of CO2 emissions regulations and limitations in the near future, utilities and power generation companies are focusing on power plant heat rate and performance. The Electric Power Research Institute (EPRI) 17th Heat Rate Improvement Conference is the latest in a series of meetings designed to assist attendees in addressing problems with power plant performance and in identifying cost-effective solutions for achieving and sustaining heat rate improve...

2011-03-28T23:59:59.000Z

Note: This page contains sample records for the topic "beta-gamma dose rates" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


321

Oxidative Stress and Skeletal Health with Low Dose, Ionizing Radiation  

NLE Websites -- All DOE Office Websites (Extended Search)

Oxidative Stress and Skeletal Health with Low Dose, Ionizing Radiation Oxidative Stress and Skeletal Health with Low Dose, Ionizing Radiation Globus Ruth NASA Ames Research Center Abstract Osteoporosis profoundly affects the aging U.S. population and exposure to high doses of radiation causes bone loss similar to age-related osteoporosis, although the influence of low dose radiation exposures is not known. The central hypothesis of our DOE project (NASA supplement) is that low doses of radiation modulate subsequent skeletal degeneration via oxidative pathways. Our working hypothesis is that a prior exposure to low dose radiation regulates oxidative metabolism within bone and contributes to bone loss caused either by subsequent high, challenge doses of radiation or by aging. HZE source: Because astronauts are exposed to radiation from GCR and solar

322

Sustainable Building Rating Systems Summary  

SciTech Connect

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

Fowler, Kimberly M.; Rauch, Emily M.

2006-07-01T23:59:59.000Z

323

Search Results for 'Credit Rating'  

U.S. Energy Information Administration (EIA)

The rating agency says it expects the bank’s asset quality to remain weak over the next 12-18 months

324

June 1 Government Rate $137  

NLE Websites -- All DOE Office Websites (Extended Search)

& Fitness Center The Jewelry Box & Gift Shoppe 24 Hour Front Desk Service, Sundry Shop, ATM Wireless Internet Always Complimentary 112 per night room rate effective thru April...

325

Exchange rate determination in Indonesia.  

E-Print Network (OSTI)

??This thesis examines the options for adopting normative and prescriptive models of exchange rate determination suitable for developed and developing countries. It also develops a… (more)

Rusydi, Mohammad

2006-01-01T23:59:59.000Z

326

Definition: Rating | Open Energy Information  

Open Energy Info (EERE)

power, such as transformers, or transport it from one location to another, such as transmission lines, the power rating almost always refers to the maximum power flow...

327

Comparative Study of Different {beta}-Radiation Doses for Preventing Pterygium Recurrence  

SciTech Connect

Purpose: To compare the pterygium recurrence rates after treatment with two different {beta}-radiation doses. Methods and Materials: A total of 84 patients with a mean age of 63.0 {+-} 10.3 years (men, 48 eyes, and women, 47 eyes) and initially treated with {beta}-radiation after pterygium excision were recruited. The mean follow-up period was 49.9 {+-} 51.3 months. The patients were assigned to two dose groups: a high-dose (40 Gy) or a low-dose (20 Gy) group. The statistical significance of differences in patient age, pterygium size, and interval between surgery and radiotherapy were analyzed in the 20-Gy group using the Cox proportional hazard model at p < .05. Results: The high- and low-dose groups included 28 and 67 eyes, respectively. Pterygia recurred in 11 eyes, all in the low-dose group. The interval between surgery and radiotherapy was not a significant predictor of recurrence. Smaller pterygia had a lower risk of recurrence than pterygia that had encroached the pupillary area (pterygium located within one-third of the corneal radius from the limbus, corrected hazard ratio [HR], 0.069; 95% confidence interval [CI], 0.006-0.766; p = .030; pterygium extending beyond one-third of the corneal radius, corrected HR, 0.188; 95% CI, 0.018-0.696; p = 0.019; and pterygium reaching the pupillary area, corrected HR, 0.184; 95% CI, 0.036-0.929; p = .040). Older age was marginally significant as a negative predictor of recurrence (HR, 0.943; 95% CI, 0.887-1.003; p = .061). No scleromalacia developed during the follow-up period. Conclusions: {beta}-Radiation at 40 Gy was more efficacious than at 20 Gy in preventing pterygium recurrence without scleromalacia development, particularly for large-size pterygia and those in young patients.

Yamada, Takayuki, E-mail: tyamada-oph@umin.ac.jp [Department of Ophthalmology and Visual Science, Hiroshima University Graduate School of Biomedical Sciences, Hiroshima (Japan); Mochizuki, Hideki [Department of Ophthalmology and Visual Science, Hiroshima University Graduate School of Biomedical Sciences, Hiroshima (Japan); Ue, Takahiro [Department of Ophthalmology, Hiroshima Red Cross and Atomic Bomb Survivors Hospital, Hiroshima (Japan); Kiuchi, Yoshiaki [Department of Ophthalmology and Visual Science, Hiroshima University Graduate School of Biomedical Sciences, Hiroshima (Japan); Takahashi, Yasuhiro [Department of Ophthalmology and Visual Science, Aichi Medical University School of Medicine, Aichi (Japan); Oinaka, Matsuyoshi [Department of Ophthalmology, Hiroshima Red Cross and Atomic Bomb Survivors Hospital, Hiroshima (Japan)

2011-12-01T23:59:59.000Z

328

Patient-Specific Monte Carlo-Based Dose-Kernel Approach for Inverse Planning in Afterloading Brachytherapy  

SciTech Connect

Purpose: Brachytherapy planning software relies on the Task Group report 43 dosimetry formalism. This formalism, based on a water approximation, neglects various heterogeneous materials present during treatment. Various studies have suggested that these heterogeneities should be taken into account to improve the treatment quality. The present study sought to demonstrate the feasibility of incorporating Monte Carlo (MC) dosimetry within an inverse planning algorithm to improve the dose conformity and increase the treatment quality. Methods and Materials: The method was based on precalculated dose kernels in full patient geometries, representing the dose distribution of a brachytherapy source at a single dwell position using MC simulations and the Geant4 toolkit. These dose kernels are used by the inverse planning by simulated annealing tool to produce a fast MC-based plan. A test was performed for an interstitial brachytherapy breast treatment using two different high-dose-rate brachytherapy sources: the microSelectron iridium-192 source and the electronic brachytherapy source Axxent operating at 50 kVp. Results: A research version of the inverse planning by simulated annealing algorithm was combined with MC to provide a method to fully account for the heterogeneities in dose optimization, using the MC method. The effect of the water approximation was found to depend on photon energy, with greater dose attenuation for the lower energies of the Axxent source compared with iridium-192. For the latter, an underdosage of 5.1% for the dose received by 90% of the clinical target volume was found. Conclusion: A new method to optimize afterloading brachytherapy plans that uses MC dosimetric information was developed. Including computed tomography-based information in MC dosimetry in the inverse planning process was shown to take into account the full range of scatter and heterogeneity conditions. This led to significant dose differences compared with the Task Group report 43 approach for the Axxent source.

D'Amours, Michel [Departement de Radio-Oncologie et Centre de Recherche en Cancerologie de l'Universite Laval, Hotel-Dieu de Quebec, Quebec, QC (Canada); Department of Physics, Physics Engineering, and Optics, Universite Laval, Quebec, QC (Canada); Pouliot, Jean [Department of Radiation Oncology, University of California, San Francisco, School of Medicine, San Francisco, CA (United States); Dagnault, Anne [Departement de Radio-Oncologie et Centre de Recherche en Cancerologie de l'Universite Laval, Hotel-Dieu de Quebec, Quebec, QC (Canada); Verhaegen, Frank [Department of Radiation Oncology, Maastro Clinic, GROW Research Institute, Maastricht University Medical Centre, Maastricht (Netherlands); Department of Oncology, McGill University, Montreal, QC (Canada); Beaulieu, Luc, E-mail: beaulieu@phy.ulaval.ca [Departement de Radio-Oncologie et Centre de Recherche en Cancerologie de l'Universite Laval, Hotel-Dieu de Quebec, Quebec, QC (Canada); Department of Physics, Physics Engineering, and Optics, Universite Laval, Quebec, QC (Canada)

2011-12-01T23:59:59.000Z

329

Validation of Dose Calculation Codes for Clearance  

SciTech Connect

Various international and national bodies such as the International Atomic Energy Agency, the European Commission, the US Nuclear Regulatory Commission have put forward proposals or guidance documents to regulate the ''clearance'' from regulatory control of very low level radioactive material, in order to allow its recycling as a material management practice. All these proposals are based on predicted scenarios for subsequent utilization of the released materials. The calculation models used in these scenarios tend to utilize conservative data regarding exposure times and dose uptake as well as other assumptions as a safeguard against uncertainties. None of these models has ever been validated by comparison with the actual real life practice of recycling. An international project was organized in order to validate some of the assumptions made in these calculation models, and, thereby, better assess the radiological consequences of recycling on a practical large scale.

Menon, S.; Wirendal, B.; Bjerler, J.; Studsvik; Teunckens, L.

2003-02-27T23:59:59.000Z

330

Low Dose Radiation Program: Links - Online Literature  

NLE Websites -- All DOE Office Websites (Extended Search)

Online Literature Online Literature Journals, Books and other Publications Armed Forces Radiobiology Research Institute Chornobyl Center for Nuclear Safety Radioactive Waste and Radioecology "Insight" Magazine Central Research Institute of the Electric Power Industry (CRIEPI) News: Aiming at an information center on low dose radiation research Health Physics International Journal of Radiation Biology Iranian Journal of Radiation Research Journal of Radiological Protection National Council on Radiation Protection and Measurements Radiation Research U.S. Department of Energy (DOE) Information Bridge Reports Animal Cancer Tests and Human Cancer Risk Assessment: A Broad Perspective Effects of Ionizing Radiation: Atomic Bomb Survivors and Their Children (1945-1995) Health Effects of Exposure to Low Levels of Ionizing Radiation: BEIR

331

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

SciTech Connect

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.

Daila S. Gridley, PhD

2012-03-30T23:59:59.000Z

332

Server efficiency rating tool (SERT)  

Science Conference Proceedings (OSTI)

The Server Efficiency Rating Tool (SERT) [1] has been developed by Standard Performance Evaluation Corporation (SPEC) [2] at the request of the US Environmental Protection Agency (EPA) [3], prompted by concerns that US datacenters consumed almost 3% ... Keywords: benchmark, datacenter, energy efficiency, energy star, environmental protection agency, epa, power, rating tool, sert, server, spec

Klaus-Dieter Lange; Mike G. Tricker; Jeremy A. Arnold; Hansfried Block; Sanjay Sharma

2012-04-01T23:59:59.000Z

333

Commercial Building Asset Rating Program  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

1 eere.energy.gov 1 eere.energy.gov Commercial Building Asset Rating Program August 23, 2011 12 p.m. ET, 9 a.m. PT Presenter: Cody Taylor PRE-DECISIONAL Information included in this document is for discussion purposes and does not constitute the final program design. FOR INFORMATION ONLY 2 eere.energy.gov Outline * Goals * Scope & schedule * Guiding principles * Program design issues - Metrics - Rating method - Rating scale - Opportunities for efficiency improvement - Quality assurance Please submit clarifying questions during today's webinar via the Q&A function of Live Meeting. 3 eere.energy.gov National Building Rating Program Goals * Facilitate cost-effective investment in energy efficiency and reduce energy use in the commercial building sector * Establish a national standard for voluntary commercial building asset rating

334

Errors and Uncertainties in Dose Reconstruction for Radiation Effects Research  

SciTech Connect

Dose reconstruction for studies of the health effects of ionizing radiation have been carried out for many decades. Major studies have included Japanese bomb survivors, atomic veterans, downwinders of the Nevada Test Site and Hanford, underground uranium miners, and populations of nuclear workers. For such studies to be credible, significant effort must be put into applying the best science to reconstructing unbiased absorbed doses to tissues and organs as a function of time. In many cases, more and more sophisticated dose reconstruction methods have been developed as studies progressed. For the example of the Japanese bomb survivors, the dose surrogate “distance from the hypocenter” was replaced by slant range, and then by TD65 doses, DS86 doses, and more recently DS02 doses. Over the years, it has become increasingly clear that an equal level of effort must be expended on the quantitative assessment of uncertainty in such doses, and to reducing and managing uncertainty. In this context, this paper reviews difficulties in terminology, explores the nature of Berkson and classical uncertainties in dose reconstruction through examples, and proposes a path forward for Joint Coordinating Committee for Radiation Effects Research (JCCRER) Project 2.4 that requires a reasonably small level of effort for DOSES-2008.

Strom, Daniel J.

2008-04-14T23:59:59.000Z

335

Veterans ’ Advisory Board on Dose Reconstruction Board member  

E-Print Network (OSTI)

Q: What is the single most important question in radiation health concerns? A: The level of risk when radiation is received gradually over time! The studies of the Japanese atomic-bomb survivors and patients who received radiological procedures and treatments have provided a wealth of knowledge on the late effects, mainly cancer, associated with moderate radiation doses received briefly at a high rate. But the issues faced today concern exposures delivered over years and not seconds, such as during occupation, medical imaging with computed tomography (CT) and nuclear medicine procedures, environmental releases such as occurred at the Fukushima accident, and the aftermath of a dirty-bomb terrorist detonation (O’Brien 2012). The existing epidemiologic data on human health effects (ICRP 2007; NCRP 2012) have been transformed and transported, modulated and manipulated, and there may be a procrustean problem (Mettler 2012). Procrustes was the mythological highwayman who cut off (or stretched on a rack) the legs of travelers so they would fit his iron bed (i.e., he forced conformity to an arbitrary set of conditions). For the Million Worker Study, there is little concern on generalizing the results to U.S. populations

John D. Boice; Ncrp President; A Study; One Million; U. S. Radiation Workers

2012-01-01T23:59:59.000Z

336

Supernova rates and stellar populations  

E-Print Network (OSTI)

We discuss the results about the nature of type Ia Supernovae that can be derived by studying their rates in different stellar populations. While the evolution of SN photometry and spectra can constrain the explosion mechanism, the SN rate depends on the progenitor system. We review the current available data on rates as a function of parent galaxy color, morphology, star formation rate, radio luminosity and environment. By studying the variation of the rates with the color of the parent galaxy, a strong evidence was established that type Ia SNe come from both young and old stars. The dependence of the rates with the radio power of the parent galaxy is best reproduced by a bimodal distribution of delay time between the formation of the progenitor and its explosion as a SN. Cluster early-type galaxies show higher type Ia SN rate with respect to field galaxies, and this effect can be due either to traces of young stars or to differences in the delay time distribution.

F. Mannucci

2007-08-03T23:59:59.000Z

337

Low Dose Radiation Research Program: Low Dose Response of Respiratory Cells  

NLE Websites -- All DOE Office Websites (Extended Search)

Response of Respiratory Cells in Intact Tissues and Reconstituted Response of Respiratory Cells in Intact Tissues and Reconstituted Tissue John Ford Department of Nuclear Engineering Texas A & M University Why this Project? Using the well-established rat trachea model to test the hypothesis that normal respiratory epithelial cells transmit signals to neighboring cells in response to very low dose radiation exposure. Project Goals By comparing the responses shown by cells in these normal rodent respiratory tissues to those seen for human respiratory epithelial cells in reconstituted tissue constructs, it will be possible to better understand the responds in human respiratory cells in vivo. These studies will characterize responses after exposure to a variety of radiation types and dose distributions. Experimental Approach

338

Low Dose Radiation Research Program: Research Program Workshop I Abstracts  

NLE Websites -- All DOE Office Websites (Extended Search)

Genetic Factors Affecting Susceptibility to Low-Dose Radiation Genetic Factors Affecting Susceptibility to Low-Dose Radiation William F. Morgan and John H.J. Petrini Radiation Oncology Research Laboratory, University of Maryland at Baltimore, Baltimore, MD Summary: The goal of our application is to improve the scientific basis for understanding potential risks to the population from low dose radiation exposure based on potential genetic differences that may modulate an individual's sensitivity to low doses of radiation. Abstract: The goal of this application is to improve the scientific basis for understanding potential risks to the population from low dose radiation exposure. We propose to address specific genetic factors that affect individual susceptibility to low dose radiation and ask the question do genetic differences exist that make some individuals more sensitive to

339

Microsoft PowerPoint - Dose Ranges 24Jan 05.ppt  

NLE Websites -- All DOE Office Websites (Extended Search)

20 40 60 20 40 60 80 100 rem NRC Dose Limit for Public 100 mrem/yr = 1 mSv/yr (DOE, ICRP, NCRP) ANSI standard N43.17 Personnel scanner, max = 25 mrem/yr Cleanup criteria for site decommissioning/ license termination 25 mrem/yr NCRP "Negligible Dose" Medical Diagnostics (A-J) A C D E G B Temporary "Special Case" annual Public Limit (NRC, DOE) NRC Dose Limit for Workers = 5 rem/yr = 50 mSv/yr Cancer Epidemiology Life Span Study (A-bomb survivors) ( Chart compiled by NF Metting, Office of Science DOE/BER; 24Jan2005,"Orders of Magnitude") Absorbed dose: 100 rad = 1 Gray Dose equivalent: 100 rem = 1 Sievert 100 mrem = 1 mSv (1 rem = 1 rad for x- and gamma- rays) Estimated dose for

340

Global methylation responses to low dose radiation exposure  

NLE Websites -- All DOE Office Websites (Extended Search)

methylation responses to low dose radiation exposure methylation responses to low dose radiation exposure Pamela J Sykes, Michelle R Newman, Benjamin J Blyth and Rebecca J Ormsby Haematology and Genetic Pathology, Flinders University and Medical Centre, Flinders Centre for Cancer Prevention and Control, Bedford Park, Adelaide, South Australia 5042 Australia. (pam.sykes@flinders.edu.au). Our goal is to study the mechanisms involved in biological responses to low doses of radiation in vivo in the dose range that is relevant to population and occupational exposures. At high radiation doses, DNA double-strand breaks are considered the critical lesion underlying the initiation of radiation-induced carcinogenesis. However, at the very low radiation doses relevant for the general public, the induction of DNA double-strand breaks

Note: This page contains sample records for the topic "beta-gamma dose rates" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


341

Technical Review of SRS Dose Reconstrruction Methods Used By CDC  

SciTech Connect

At the request of the Centers for Disease Control and Prevention (CDC), a subcontractor Advanced Technologies and Laboratories International, Inc.(ATL) issued a draft report estimating offsite dose as a result of Savannah River Site operations for the period 1954-1992 in support of Phase III of the SRS Dose Reconstruction Project. The doses reported by ATL differed than those previously estimated by Savannah River Site SRS dose modelers for a variety of reasons, but primarily because (1) ATL used different source terms, (2) ATL considered trespasser/poacher scenarios and (3) ATL did not consistently use site-specific parameters or correct usage parameters. The receptors with the highest dose from atmospheric and liquid pathways were within about a factor of four greater than dose values previously reported by SRS. A complete set of technical comments have also been included.

Simpkins, Ali, A

2005-07-20T23:59:59.000Z

342

Radiotherapy Dose-Volume Effects on Salivary Gland Function  

Science Conference Proceedings (OSTI)

Publications relating parotid dose-volume characteristics to radiotherapy-induced salivary toxicity were reviewed. Late salivary dysfunction has been correlated to the mean parotid gland dose, with recovery occurring with time. Severe xerostomia (defined as long-term salivary function of gland is spared to a mean dose of less than {approx}20 Gy or if both glands are spared to less than {approx}25 Gy (mean dose). For complex, partial-volume RT patterns (e.g., intensity-modulated radiotherapy), each parotid mean dose should be kept as low as possible, consistent with the desired clinical target volume coverage. A lower parotid mean dose usually results in better function. Submandibular gland sparing also significantly decreases the risk of xerostomia. The currently available predictive models are imprecise, and additional study is required to identify more accurate models of xerostomia risk.

Deasy, Joseph O., E-mail: jdeasy@radonc.wustl.ed [Department of Radiation Oncology, Washington University School of Medicine and Alvin J. Siteman Cancer Center, St. Louis, MO (United States); Moiseenko, Vitali [Department of Medical Physics, British Columbia Cancer Agency-Vancouver Cancer Center, Vancouver, BC (Canada); Marks, Lawrence [Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, NC (United States); Chao, K.S. Clifford [Department of Radiation Oncology, Columbia School of Medicine, New York, NY (United States); Nam, Jiho [Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, NC (United States); Eisbruch, Avraham [Department of Radiation Oncology, University of Michigan School of Medicine, Ann Arbor, MI (United States)

2010-03-01T23:59:59.000Z

343

DOE Guidance-Category Rating  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

2010 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 alternative rating proced.ures in assessing applicants for employment using category rating and selection procedures, and to ensure consistency in complying with federal regulations contained in the Code of Federal Regulations (CFR), Office of Personnel Management (OPM) and the Department of

344

ARM - Measurement - Radiative heating rate  

NLE Websites -- All DOE Office Websites (Extended Search)

govMeasurementsRadiative heating rate 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 Radiometric, Atmospheric State Instruments The above measurement is considered scientifically relevant for the following instruments. Refer to the datastream (netcdf) file headers of each instrument for a list of all available measurements, including those recorded for diagnostic or quality assurance purposes. External Instruments MOLTS : Model Output Location Time Series Datastreams MOLTS : Model Output Location Time Series Datastreams MOLTSEDASSNDCLASS1 : Model Output Loc. Time Ser. (MOLTS): EDAS

345

OpenEI - electric rates  

Open Energy Info (EERE)

U.S. Electric Utility U.S. Electric Utility Companies and Rates: Look-up by Zipcode (Feb 2011) http://en.openei.org/datasets/node/899 This dataset, compiled by NREL and Ventyx, provides average residential, commercial and industrial electricity rates by zip code for both investor owned utilities (IOU) and non-investor owned utilities. Note: the file includes average rates for each utility, but not the detailed rate structure data found in the database available via the zip-code look-up feature on the OpenEI Utilities page (http://en.openei.org/wiki/Gateway:Utilities). The data was released by NREL/Ventyx in February 2011.

346

Project Definition Rating Index (PDRI)  

Energy.gov (U.S. Department of Energy (DOE))

The Office of Environmental Management (EM) Project Definition Rating Index (EM-PDRI) is a modification of a commercially developed planning tool that has been tested by an EM team specifically for...

347

Heat Rate Improvement Reference Manual  

Science Conference Proceedings (OSTI)

Performance optimization of fossil power plants is a high priority within the electric utilities in the new competitive environment. This manual can help utility engineers establish a heat rate improvement program.

1998-07-27T23:59:59.000Z

348

Exchange Rates, Information, and Crises  

E-Print Network (OSTI)

equation (5.4). Standard Bayesian inference implies that theAs before, standard Bayesian inference implies that Var 1 [f˜ so that standard Bayesian inference both exchange rate is

Fernholz, Ricardo Turrin

2011-01-01T23:59:59.000Z

349

High compression rate text summarization  

E-Print Network (OSTI)

This thesis focuses on methods for condensing large documents into highly concise summaries, achieving compression rates on par with human writers. While the need for such summaries in the current age of information overload ...

Branavan, Satchuthananthavale Rasiah Kuhan

2008-01-01T23:59:59.000Z

350

Low Dose Radiation Research Program: X-ray Microbeam Bystander...  

NLE Websites -- All DOE Office Websites (Extended Search)

experiments, cultures grown in microwell slide chambers were irradiated with precise stripes of dose up to 100m wide. Samples were processed for the expression of...

351

Consequences of low dose irradiation in the CNS  

NLE Websites -- All DOE Office Websites (Extended Search)

Consequences of low dose irradiation in the CNS Bertrand Tseng, Munjal M. Acharya, Neal Patel, Katherine Tran, Mary Lan, Erich Giedzinski, Vipan Kumar and Charles Limoli Department...

352

Impact of Low-Dose Ionizing Irradiation on Histone Modification...  

NLE Websites -- All DOE Office Websites (Extended Search)

Impact of Low-Dose Ionizing Irradiation on Histone Modification and Chromatin Organization Hunter W. Richards Lawrence Berkeley National Laboratory Abstract Goal Our goal is to...

353

Impact of Low-Dose Ionizing Irradiation on Histone Modification...  

NLE Websites -- All DOE Office Websites (Extended Search)

Low-Dose Ionizing Irradiation on Histone Modification and Chromatin Organization Hunter W. Richards, Steven D. Ayers, Shutao Cai, Yoshinori Kohwi, Gary Karpen, Sylvain Costes and...

354

Low Dose Radiation Research Program: Past Funded Projects-Archive  

NLE Websites -- All DOE Office Websites (Extended Search)

Berkeley, CA A Quantitative Assessment of Bystander Mutagenesis in the Mouse Mammary Gland In Vivo Bruce E. Lehnert Los Alamos National Laboratory, Los Alamos, NM Low Dose...

355

Low Dose Radiation Research Program: 2011 Current Projects  

NLE Websites -- All DOE Office Websites (Extended Search)

Investigation of non-targeted effects of low dose ionizing radiation on the mammary gland utilizing three-dimensional culture models of mammary cells derived from mouse strains...

356

Hanford Environmental Dose Reconstruction Project. Monthly report, June 1992  

Science Conference Proceedings (OSTI)

The objective of the Hanford Environmental Dose Reconstruction Project is to estimate the radiation doses that individuals and populations could have received from nuclear operations at Hanford since 1944. The project is being managed and conducted by the Battelle Pacific Northwest Laboratories under contract with the Centers for Disease Control. 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; environmental pathways and dose estimates.

Finch, S.M.; McMakin, A.H. [comps.

1992-06-01T23:59:59.000Z

357

Low Dose Radiation Research Program: Research Highlights - Ionizing...  

NLE Websites -- All DOE Office Websites (Extended Search)

of Energy Low Dose Radiation Research Program, and the Department of Defense Breast Cancer Research program and Prostate Cancer Research program. Researchers include Eva...

358

Low Dose Radiation Research Program: Quantification of Repair...  

NLE Websites -- All DOE Office Websites (Extended Search)

Quantification of Repair of Low-Dose-Induced DNA Double-Strand Breaks in Diploid Human Cells David Schild Lawrence Berkeley National Laboratory Berkeley, California Why this...

359

Low Dose Radiation Research Program: Assessing Biological Function...  

NLE Websites -- All DOE Office Websites (Extended Search)

Livermore National Laboratory under contract No. W-7405-ENG-48 and funded by the Low Dose Radiation Research Program, Biological and Environmental Research (BER), U.S....

360

Low Dose Radiation Research Program: Genetic Variation in Tissue...  

NLE Websites -- All DOE Office Websites (Extended Search)

Variation in Tissue Responses to Low-dose Radiation Eugene Rinchik Oak Ridge National Laboratory Why this Project? To address how individual genetic background affects tissue...

Note: This page contains sample records for the topic "beta-gamma dose rates" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

Low Dose Program Highlight: Do Heritable Differences in an Individual...  

NLE Websites -- All DOE Office Websites (Extended Search)

Differences in an Individual's Immune System Predict Differential Sensitivity to Low Dose Radiation Exposure? Brynn Voy, University of Tennessee Knoxville, and Oak Ridge...

362

Low dose radiation combines with the Src oncoproteinto transform...  

NLE Websites -- All DOE Office Websites (Extended Search)

Lawrence Berkeley National Laboratory, Berkeley CA 94720 Goal: Determine whether low dose radiation exerts persistent epigenetic effects that promote malignancy. Background and...

363

Low Dose Radiation Research Program: Radiation Response in Normal...  

NLE Websites -- All DOE Office Websites (Extended Search)

genes. Using rigorous computational methods, we characterized the dose-dependent, radiation-induced gene expression of HSF-42, a primary cell culture. Our preliminary results...

364

Low-Dose Radiation Cataract and Genetic Determinants of Radiosensitivi...  

NLE Websites -- All DOE Office Websites (Extended Search)

Our research utilizes radiation cataract as a model system to study the effects of low-dose ionizing radiation exposure in a complex, highly differentiated tissue. We believe...

365

Low Dose Radiation Research Program: Bruce N. Ames  

NLE Websites -- All DOE Office Websites (Extended Search)

University of California, Berkeley Technical Abstracts 2002 Workshop: Comparison of Low-Dose Radiation, Endogenous Oxidants, and Micronutrient Deficiencies through Analyses of DNA...

366

Low Dose Radiation Research Program: Gene Expression Profiles...  

NLE Websites -- All DOE Office Websites (Extended Search)

of Energy by the University of California, Lawrence Livermore National Laboratory under Contract No. W-7405-Eng-48 with funding from the DOE Low Dose Radiation Research Program...

367

Low Dose Radiation Research Program: Susan S. Wallace  

NLE Websites -- All DOE Office Websites (Extended Search)

Susan S. Wallace University of Vermont Past Funded Project Free Radical DNA Damage Produced Endogenously and by Low Dose Radiation in Human Cells: Quantitation, Consequences, and...

368

Risk equivalent of exposure versus dose of radiation  

SciTech Connect

This report describes a risk analysis study of low-dose irradiation and the resulting biological effects on a cell. The author describes fundamental differences between the effects of high-level exposure (HLE) and low-level exposure (LLE). He stresses that the concept of absorbed dose to an organ is not a dose but a level of effect produced by a particular number of particles. He discusses the confusion between a linear-proportional representation of dose limits and a threshold-curvilinear representation, suggesting that a LLE is a composite of both systems. (TEM)

Bond, V.P.

1986-01-01T23:59:59.000Z

369

Photon Absorbed-Dose-to-Water Primary Standards  

Science Conference Proceedings (OSTI)

Photon Absorbed-Dose-to-Water Primary Standards. ... and scattering/perturbation for the water calorimeter in both Co-60 and high-energy x-ray ...

2013-03-08T23:59:59.000Z

370

A Successful Cool Storage Rate  

E-Print Network (OSTI)

Houston Lighting & Power (HL&P) initiated design and development of its commercial cool storage program as part of an integrated resource planning process with a targeted 225 MW of demand reduction through DSM. Houston's extensive commercial air conditioning load, which is highly coincident with HL&P's system peak, provided a large market for cool storage technologies. Initial market research made it very clear that a special cool storage rate was required to successfully market the technology. Development of the rate required an integrated, multidepartment effort and extensive use of DSManager, an integrated resource planning model. An experimental version of the rate was initially implemented as part of the initial phase of the cool storage program. A permanent rate, incorporating lessons learned from the experimental rate, was then developed for the long term implementation of the program. The permanent rate went through a lengthy regulatory approval process which included intervention by a local natural gas distribution company. The end result is a very successful cool storage program with 52 projects and 31 megawatts of demand reduction in the first three and one-half years of program implementation.

Ahrens, A. C.; Sobey, T. M.

1994-01-01T23:59:59.000Z

371

Low-dose Photon and Simulated Solar Particle Event Proton Effects on Foxp3+  

NLE Websites -- All DOE Office Websites (Extended Search)

Photon and Simulated Solar Particle Event Proton Effects on Foxp3+ Photon and Simulated Solar Particle Event Proton Effects on Foxp3+ Treg Cells and Other Leukocytes Daila Gridley Loma Linda University and Medical Center Abstract Purpose: Radiation is a major factor in the spaceflight environment that can compromise immune defense mechanisms. Astronauts on missions are continuously exposed to lowdose/ low-dose-rate (LDR) radiation and may receive relatively high doses during a solar particle event (SPE) that consists primarily of protons. However, there are very few reports in which LDR photons were combined with protons. The goal of this study was to determine whether exposure to LDR γ-rays would modulate the effect of proton radiation mimicking an SPE. Materials and Methods: C57BL/6 mice were exposed to 1.7 Gy simulated SPE

372

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

DOE Green Energy (OSTI)

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.

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

2003-07-01T23:59:59.000Z

373

Mechanisms Underlying Cellular Responses to Low Doses/Low LET Ionizing Radiation in Primary Haemopoietic Cells.  

NLE Websites -- All DOE Office Websites (Extended Search)

Mechanisms Underlying Cellular Responses to Low Doses/Low LET Ionizing Radiation Mechanisms Underlying Cellular Responses to Low Doses/Low LET Ionizing Radiation in Primary Haemopoietic Cells. Munira Kadhim 1 , Stefania Militi 1 , Debbie Bowler 1 , Denise Macdonald 1 and Kevin Prise 2 1 Radiation and Genome Stability Unit, MRC, Harwell, Didcot, Oxon, OX11 0RD, UK 2 Gray Cancer Institute ,PO Box 100, Mount Vernon Hospital, Northwood, HA6 2JR, UK Because the human population is genetically heterogeneous, it is important to understand the role that heterogeneity may play in radiation response. Exposure to ionizing radiation can lead to a suite of changes, including increased mutation rate, delayed reproductive cell death, and delayed chromosomal aberrations, all of which are manifestations of the complex genomic instability (GI) phenotype. Following exposure to either high LET

374

A Comparison of Dose-Response Models for the Parotid Gland in a Large Group of Head-and-Neck Cancer Patients  

Science Conference Proceedings (OSTI)

Purpose: The dose-response relationship of the parotid gland has been described most frequently using the Lyman-Kutcher-Burman model. However, various other normal tissue complication probability (NTCP) models exist. We evaluated in a large group of patients the value of six NTCP models that describe the parotid gland dose response 1 year after radiotherapy. Methods and Materials: A total of 347 patients with head-and-neck tumors were included in this prospective parotid gland dose-response study. The patients were treated with either conventional radiotherapy or intensity-modulated radiotherapy. Dose-volume histograms for the parotid glands were derived from three-dimensional dose calculations using computed tomography scans. Stimulated salivary flow rates were measured before and 1 year after radiotherapy. A threshold of 25% of the pretreatment flow rate was used to define a complication. The evaluated models included the Lyman-Kutcher-Burman model, the mean dose model, the relative seriality model, the critical volume model, the parallel functional subunit model, and the dose-threshold model. The goodness of fit (GOF) was determined by the deviance and a Monte Carlo hypothesis test. Ranking of the models was based on Akaike's information criterion (AIC). Results: None of the models was rejected based on the evaluation of the GOF. The mean dose model was ranked as the best model based on the AIC. The TD{sub 50} in these models was approximately 39 Gy. Conclusions: The mean dose model was preferred for describing the dose-response relationship of the parotid gland.

Houweling, Antonetta C., E-mail: A.Houweling@umcutrecht.n [Department of Radiotherapy, University Medical Center Utrecht, Utrecht (Netherlands); Philippens, Marielle E.P.; Dijkema, Tim; Roesink, Judith M. [Department of Radiotherapy, University Medical Center Utrecht, Utrecht (Netherlands); Terhaard, Chris H.J. [Department of Radiation Oncology, University Medical Center Groningen, Croningen (Netherlands); Schilstra, Cornelis; Ten Haken, Randall K.; Eisbruch, Avraham [Department of Radiation Oncology, University of Michigan, Ann Arbor, MI (United States); Raaijmakers, Cornelis P.J. [Department of Radiotherapy, University Medical Center Utrecht, Utrecht (Netherlands)

2010-03-15T23:59:59.000Z

375

Large Cohort Dose-Volume Response Analysis of Parotid Gland Function After Radiotherapy: Intensity-Modulated Versus Conventional Radiotherapy  

Science Conference Proceedings (OSTI)

Purpose: To compare parotid gland dose-volume response relationships in a large cohort of patients treated with intensity-modulated (IMRT) and conventional radiotherapy (CRT). Methods and materials: A total of 221 patients (64 treated with IMRT, 157 with CRT) with various head-and-neck malignancies were prospectively evaluated. The distribution of tumor subsites in both groups was unbalanced. Stimulated parotid flow rates were measured before and 6 weeks, 6 months, and 1 year after radiotherapy. Parotid gland dose-volume histograms were derived from computed tomography-based treatment planning. The normal tissue complication probability (NTCP) model proposed by Lyman was fit to the data. A complication was defined as stimulated parotid flow ratio gland dose using Poisson regression modeling. Results: One year after radiotherapy, NTCP curves for IMRT and CRT were comparable with a TD{sub 50} (uniform dose leading to a 50% complication probability) of 38 and 40 Gy, respectively. Until 6 months after RT, corrected for mean dose, different complication probabilities existed for IMRT vs. CRT. The relative risk of a complication for IMRT vs. CRT after 6 weeks was 1.42 (95% CI 1.21-1.67), after 6 months 1.41 (95% CI; 1.12-1.77), and at 1 year 1.21 (95% CI 0.87-1.68), after correcting for mean dose. Conclusions: One year after radiotherapy, no difference existed in the mean dose-based NTCP curves for IMRT and CRT. Early after radiotherapy (up to 6 months) mean dose based (Lyman) models failed to fully describe the effects of radiotherapy on the parotid glands.

Dijkema, Tim [Department of Radiation Oncology, University Medical Center Utrecht, Utrecht (Netherlands)], E-mail: T.Dijkema@umcutrecht.nl; Terhaard, Chris H.J.; Roesink, Judith M.; Braam, Petra M. [Department of Radiation Oncology, University Medical Center Utrecht, Utrecht (Netherlands); Gils, Carla H. van [Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, Utrecht (Netherlands); Moerland, Marinus A.; Raaijmakers, Cornelis P.J. [Department of Radiation Oncology, University Medical Center Utrecht, Utrecht (Netherlands)

2008-11-15T23:59:59.000Z

376

Program on Technology Innovation: Evaluation of Updated Research on the Health Effects and Risks Associated with Low-Dose Ionizing Radiation  

Science Conference Proceedings (OSTI)

The Electric Power Research Institute (EPRI) has performed a systematic review of recently published, peer-reviewed scientific studies in the fields of epidemiology and radiobiology that discuss health risks associated with exposure to low levels of ionizing radiation. As a result of this study, the EPRI team concludes that there is a need to re-evaluate the magnitude of dose and dose-rate effectiveness factors (DDREF), including the significant body of radiobiology data that suggests non-linear risks at...

2009-11-18T23:59:59.000Z

377

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

Science Conference Proceedings (OSTI)

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.

Hardcastle, Nicholas; Bayliss, Adam; Wong, Jeannie Hsiu Ding; Rosenfeld, Anatoly B.; Tome, Wolfgang A. [Department of Human Oncology, University of Wisconsin-Madison, WI, 53792 (United States); Department of Physical Sciences, Peter MacCallum Cancer Centre, Melbourne, VIC 3002 (Australia) and Centre for Medical Radiation Physics, University of Wollongong, Wollongong, NSW 2522 (Australia); Department of Human Oncology, University of Wisconsin-Madison, WI 53792 (United States); Centre for Medical Radiation Physics, University of Wollongong, Wollongong, NSW 2522 (Australia) and Department of Biomedical Imaging, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur (Malaysia); Centre for Medical Radiation Physics, University of Wollongong, Wollongong, NSW 2522 (Australia); Department of Medical Physics, University of Wisconsin-Madison, Madison, Wisconsin 53792 (United States); Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53792 (United States); Einstein Institute of Oncophysics, Albert Einstein College of Medicine of Yeshiva University, Bronx, New York 10461 (United States) and Centre for Medical Radiation Physics, University of Wollongong, Wollongong, NSW 2522 (Australia)

2012-08-15T23:59:59.000Z

378

Dose Escalation for Metastatic Spinal Cord Compression in Patients With Relatively Radioresistant Tumors  

SciTech Connect

Purpose: Radiotherapy alone is the most common treatment for metastatic spinal cord compression (MSCC) from relatively radioresistant tumors such as renal cell carcinoma, colorectal cancer, and malignant melanoma. However, the results of the 'standard' regimen 30 Gy/10 fractions need to be improved with respect to functional outcome. This study investigated whether a dose escalation beyond 30 Gy can improve treatment outcomes. Methods and Materials: A total of 91 patients receiving 30 Gy/10 fractions were retrospectively compared to 115 patients receiving higher doses (37.5 Gy/15 fractions, 40 Gy/20 fractions) for motor function and local control of MSCC. Ten further potential prognostic factors were evaluated: age, gender, tumor type, performance status, number of involved vertebrae, visceral or other bone metastases, interval from tumor diagnosis to radiotherapy, pretreatment ambulatory status, and time developing motor deficits before radiotherapy. Results: Motor function improved in 18% of patients after 30 Gy and in 22% after higher doses (p = 0.81). On multivariate analysis, functional outcome was associated with visceral metastases (p = 0.030), interval from tumor diagnosis to radiotherapy (p = 0.010), and time developing motor deficits (p < 0.001). The 1-year local control rates were 76% after 30 Gy and 80% after higher doses, respectively (p = 0.64). On multivariate analysis, local control was significantly associated with visceral metastases (p = 0.029) and number of involved vertebrae (p = 0.043). Conclusions: Given the limitations of a retrospective study, escalation of the radiation dose beyond 30 Gy/10 fractions did not significantly improve motor function and local control of MSCC in patients with relatively radioresistant tumors.

Rades, Dirk, E-mail: Rades.Dirk@gmx.net [Department of Radiation Oncology, University of Lubeck (Germany); Freundt, Katja; Meyners, Thekla [Department of Radiation Oncology, University of Lubeck (Germany); Bajrovic, Amira [Department of Radiation Oncology, University of Hamburg (Germany); Basic, Hiba [Department of Radiation Oncology, University of Sarajevo (Bosnia and Herzegowina); Karstens, Johann H. [Department of Radiation Oncology, Medical School Hannover (Germany); Adamietz, Irenaeus A. [Department of Radiation Oncology, Ruhr University Bochum (Germany); Wildfang, Ingeborg [Department of Radiation Oncology, Siloah Hospital Hannover (Germany); Rudat, Volker [Department of Radiation Oncology, Saad Specialist Hospital Al-Khobar (Saudi Arabia); Schild, Steven E. [Department of Radiation Oncology, Mayo Clinic Scottsdale, Scottsdale, AZ (United States); Dunst, Juergen [Department of Radiation Oncology, University of Lubeck (Germany)

2011-08-01T23:59:59.000Z

379

Standard Rates, Budget Office, Brookhaven National Laboratory...  

NLE Websites -- All DOE Office Websites (Extended Search)

Standard Rates Standard Rates for Brookhaven National Laboratory is available in PDF file formats. This file contains rates for Distributed Technical Services, Scientific Devices...

380

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

Science Conference Proceedings (OSTI)

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

Dooling, J.; Accelerator Systems Division (APS)

2010-11-01T23:59:59.000Z

Note: This page contains sample records for the topic "beta-gamma dose rates" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


381

Low Dose Radiation Research Program: Gene Expression Profile...  

NLE Websites -- All DOE Office Websites (Extended Search)

human cDNA clones, we focused on differential gene expression for a low-dose x-ray irradiation at 2cGy and its comparison with high-dose at 4Gy. Four time points were studied at...

382

An internal dose monitoring program at an academic research institution  

E-Print Network (OSTI)

This thesis describes the development of an internal dose monitoring program for radioactive material based on the recommendations of the International Commission on Radiological Protection (ICRP) in Publication 26, "Recommendations of the International Commission on Radiological Protection" and the regulatory requirements contained in Title 10, Part 20 of the Code of Federal Regulations, "Standards for Protection Against Radiation". The elements of an internal dose monitoring program were reviewed as a prelude to evaluating the internal dose monitoring program at Texas A&M University. A revised internal dose monitoring program was proposed. Identification of individuals required to participate in the internal dose monitoring program was based on methodology adapted from NUREG 1400, "Air Sampling in the Workplace". A review of radioactive material use for 1996 and the bioassay records from 1980 through 1996 was used to determine radionuclide use levels to identify participants eligible for routine and confirmatory bioassays and to develop a schedule for monitoring personnel who are eligible for bioassays. Methods to calculate intake and assess dose using bioassay data were chosen. Action levels were established as percentages of the applicable regulatory dose limits. Bioassay report forms were developed and the requirements for recording results and reporting the dose assessment to regulatory agencies were established.

Carsten, Keith Eric

1997-01-01T23:59:59.000Z

383

LINEAR COUNT-RATE METER  

DOE Patents (OSTI)

A linear count-rate meter is designed to provide a highly linear output while receiving counting rates from one cycle per second to 100,000 cycles per second. Input pulses enter a linear discriminator and then are fed to a trigger circuit which produces positive pulses of uniform width and amplitude. The trigger circuit is connected to a one-shot multivibrator. The multivibrator output pulses have a selected width. Feedback means are provided for preventing transistor saturation in the multivibrator which improves the rise and decay times of the output pulses. The multivibrator is connected to a diode-switched, constant current metering circuit. A selected constant current is switched to an averaging circuit for each pulse received, and for a time determined by the received pulse width. The average output meter current is proportional to the product of the counting rate, the constant current, and the multivibrator output pulse width.

Henry, J.J.

1961-09-01T23:59:59.000Z

384

Coal Transportation Rate Sensitivity Analysis  

Reports and Publications (EIA)

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 coalconsumption 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.

John Conti

2005-04-01T23:59:59.000Z

385

Billiards with polynomial mixing rates  

E-Print Network (OSTI)

While many dynamical systems of mechanical origin, in particular billiards, are strongly chaotic -- enjoy exponential mixing, the rates of mixing in many other models are slow (algebraic, or polynomial). The dynamics in the latter are intermittent between regular and chaotic, which makes them particularly interesting in physical studies. However, mathematical methods for the analysis of systems with slow mixing rates were developed just recently and are still difficult to apply to realistic models. Here we reduce those methods to a practical scheme that allows us to obtain a nearly optimal bound on mixing rates. We demonstrate how the method works by applying it to several classes of chaotic billiards with slow mixing as well as discuss a few examples where the method, in its present form, fails.

Nikolai Chernov; Hong-Kun Zhang

2004-09-12T23:59:59.000Z

386

Testicular Doses in Image-Guided Radiotherapy of Prostate Cancer  

Science Conference Proceedings (OSTI)

Purpose: To investigate testicular doses contributed by kilovoltage cone-beam computed tomography (kVCBCT) during image-guided radiotherapy (IGRT) of prostate cancer. Methods and Materials: An EGS4 Monte Carlo code was used to calculate three-dimensional dose distributions from kVCBCT on 3 prostate cancer patients. Absorbed doses to various organs were compared between intensity-modulated radiotherapy (IMRT) treatments and kVCBCT scans. The impact of CBCT scanning mode, kilovoltage peak energy (kVp), and CBCT field span on dose deposition to testes and other organs was investigated. Results: In comparison with one 10-MV IMRT treatment, a 125-kV half-fan CBCT scan delivered 3.4, 3.8, 4.1, and 5.7 cGy to the prostate, rectum, bladder, and femoral heads, respectively, accounting for 1.7%, 3.2%, 3.2%, and 8.4% of megavoltage photon dose contributions. However, the testes received 2.9 cGy from the same CBCT scan, a threefold increase as compared with 0.7 cGy received during IMRT. With the same kVp, full-fan mode deposited much less dose to organs than half-fan mode, ranging from 9% less for prostate to 69% less for testes, except for rectum, where full-fan mode delivered 34% more dose. As photon beam energy increased from 60 to 125 kV, kVCBCT-contributed doses increased exponentially for all organs, irrespective of scanning mode. Reducing CBCT field span from 30 to 10 cm in the superior-inferior direction cut testicular doses from 5.7 to 0.2 cGy in half-fan mode and from 1.5 to 0.1 cGy in full-fan mode. Conclusions: Compared with IMRT, kVCBCT-contributed doses to the prostate, rectum, bladder, and femoral heads are clinically insignificant, whereas dose to the testes is threefold more. Full-fan CBCT usually deposits much less dose to organs (except for rectum) than half-fan mode in prostate patients. Kilovoltage CBCT-contributed doses increase exponentially with photon beam energy. Reducing CBCT field significantly cuts doses to testes and other organs.

Deng Jun, E-mail: jun.deng@yale.edu [Department of Therapeutic Radiology, Yale University, New Haven, CT (United States); Chen Zhe; Yu, James B.; Roberts, Kenneth B.; Peschel, Richard E.; Nath, Ravinder [Department of Therapeutic Radiology, Yale University, New Haven, CT (United States)

2012-01-01T23:59:59.000Z

387

Low Dose Radiation Research Program: Induction of Genomic Instability in  

NLE Websites -- All DOE Office Websites (Extended Search)

Induction of Genomic Instability in vivo by Low Doses of 137Cs y Induction of Genomic Instability in vivo by Low Doses of 137Cs y rays, Authors: K. Rithidech1, E.B. Whorton2, M. Tungjai1, E. Ar-Bab1, S.R. Simon1, M. Tawde3 and C.W. Anderson3. Institutions: 1Pathology Department, Stony Brook University, NY 11794-8691, USA, 2University of Texas Medical Branch at Galveston, TX 77550-1047,3Biology Department, Brookhaven National Laboratory, Upton, NY 11973-5000. Information on potential health hazards of radiation at doses below or equal to the level traditionally requiring human radiation protection (less than or equal to 10 cGy) is currently lacking. It is therefore important to characterize early and subsequent in vivo biological response induced by low doses of ionizing radiation because such data should provide information that can help determine whether radiation at this dose level

388

ORISE: Dose Coefficients for Intakes of Radionuclides via Contaminated  

NLE Websites -- All DOE Office Websites (Extended Search)

Dose Coefficients for Intakes of Radionuclides via Contaminated Wounds Dose Coefficients for Intakes of Radionuclides via Contaminated Wounds Dose coefficients for 38 radionuclides based on NCRP Wound Model and ICRP biokinetic models This report is intended to assist health physics and medical staff in more rapidly assessing the potential dosimetric consequences of a contaminated wound. The National Council on Radiation Protection and Measurements Wound Model describing the retention of selected radionuclides at the site of a contaminated wound and their uptake into the transfer compartment has been combined with the International Commission on Radiological Protection element-specific systemic models for those radionuclides to derive dose coefficients for intakes via contaminated wounds. Examples are also provided on using the dose coefficients to generate derived reference

389

Chronic Low Dose Radiation Effects on Radiation Sensitivity  

NLE Websites -- All DOE Office Websites (Extended Search)

Chronic Low Dose Radiation Effects on Radiation Sensitivity Chronic Low Dose Radiation Effects on Radiation Sensitivity and Chromosome Instability Induction in TK6 Cells Schwartz J.L. 1 , Jordan R. 1 , Slovic J. 1 , Moruzzi A. 1 , Kimmel R. 2 , and Liber, H.L. 3 1 University of Washington, Seattle, WA; 2 Fred Hutchinson Cancer Research Center, Seattle, WA; 3 Colorado State University, Fort Collins, Colorado There are a number of cell responses that can be detected after low dose radiation exposures including the adaptive response, low dose hypersensitivity, and induced genomic instability. The relationship between these different phenomena is unknown. In this study, we measured adaptive responses, low dose hypersensitivity, and induced genomic instability in a human B-lymphoblastoid cell model, TK6, where we could genetically modify radiation responses by either over-expression of BCL-2 or deletion of TP53. TK6

390

IMPRINTED GENES & TRANSPOSITIONS: EPIGENOMIC TARGETS FOR LOW DOSE RADIATION EFFECTS  

Science Conference Proceedings (OSTI)

The overall hypothesis of this grant application is that low dose ionizing radiation (LDIR) elicits adaptive responses in part by causing heritable DNA methylation changes in the epigenome. This novel postulate was tested by determining if the level of DNA methylation at the Agouti viable yellow (A{sup vy}) metastable locus is altered, in a dose-dependent manner, by low dose radiation exposure (radiation hormesis, bringing into question the assumption that every dose of radiation is harmful. Our findings not only have significant implications concerning the mechanism of hormesis, but they also emphasize the potential importance of this phenomenon in determining human risk at low radiation doses. Since the epigenetic regulation of genes varies markedly between species, the effect of LDIR on other epigenetically labile genes (e.g. imprinted genes) in animals and humans needs to be defined.

Randy Jirtle

2012-10-11T23:59:59.000Z

391

ACDOS1: A COMPUTER CODE TO CALCULATE DOSE RATES FROM NEUTRON ACTIVATION OF NEUTRAL BEAMLINES AND OTHER FUSION REACTOR COMPONENTS  

E-Print Network (OSTI)

TD THE LAST 1/E GROUP 1TFR.1 NGPl-NCEGPS+l Z^MER>GUESSI* XSUBI-ZM.MER/ IEXP1(GP(NGPl i-GPINOEGPS »1/GUESS 11-11-

Keney, G.S.

2010-01-01T23:59:59.000Z

392

ACDOS1: A COMPUTER CODE TO CALCULATE DOSE RATES FROM NEUTRON ACTIVATION OF NEUTRAL BEAMLINES AND OTHER FUSION REACTOR COMPONENTS  

E-Print Network (OSTI)

the Tokamak Fusion Test Reactor Test Cell", Nucl. Technol.BEAMLINES AND OTHER FUSION--REACTOR COMPONENTS Gregory S.Beamlines and Other Fusion-Reactor Compon­ ents By Gregory

Keney, G.S.

2010-01-01T23:59:59.000Z

393

ACDOS1: A COMPUTER CODE TO CALCULATE DOSE RATES FROM NEUTRON ACTIVATION OF NEUTRAL BEAMLINES AND OTHER FUSION REACTOR COMPONENTS  

E-Print Network (OSTI)

BEAMLINES AND OTHER FUSION--REACTOR COMPONENTS Gregory S.Beamlines and Other Fusion-Reactor Compon­ ents By Gregoryin the Tokamak Fusion Test Reactor Test Cell", Nucl.

Keney, G.S.

2010-01-01T23:59:59.000Z

394

The impact of ventilation rate on the emission rates of volatile...  

NLE Websites -- All DOE Office Websites (Extended Search)

impact of ventilation rate on the emission rates of volatile organic compounds in residences Title The impact of ventilation rate on the emission rates of volatile organic...

395

Hardware implementation of wireless bit rate adaptation  

E-Print Network (OSTI)

This thesis presents a hardware implementation of the SoftRate bit-rate adaptation protocol. SoftRate is a new bit-rate adaptation protocol, which uses per-bit confidence hints generated by the convolutional decoder to ...

Gross, Samuel A

2010-01-01T23:59:59.000Z

396

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

SciTech Connect

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.

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

2011-11-11T23:59:59.000Z

397

Energy Efficiency Interest Rate Reduction Program | Department...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Interest Rate Reduction Program Energy Efficiency Interest Rate Reduction Program Eligibility Residential Savings For Heating & Cooling Home Weatherization Construction Commercial...

398

Building Energy Performance Certificate. Asset Rating.  

U.S. Energy Information Administration (EIA)

Non-Domestic Building Energy Performance Asset Rating ... Asset Rating. Author: BRE Subject: LCEA029636 Keywords: Energy Performance Certificate ...

399

Property:OpenEI/UtilityRate/DemandRateStructure/Tier4Rate | Open Energy  

Open Energy Info (EERE)

Rate" Rate" Showing 13 pages using this property. 4 4b524791-bef2-49b1-850b-458730755203 + 5 +, 6 +, 3 +, ... 4b524791-bef2-49b1-850b-458730755203 + 6 + 4b524791-bef2-49b1-850b-458730755203 + 3 + 4b524791-bef2-49b1-850b-458730755203 + 7 + 4b524791-bef2-49b1-850b-458730755203 + 5 + 4b524791-bef2-49b1-850b-458730755203 + 8 + 4b524791-bef2-49b1-850b-458730755203 + 5 + 4b524791-bef2-49b1-850b-458730755203 + 5 + 4b524791-bef2-49b1-850b-458730755203 + 6 + 4b524791-bef2-49b1-850b-458730755203 + 6 + E E40880ac-c27b-4cbf-a011-b0d7d6e10fe9 + 1 + E40880ac-c27b-4cbf-a011-b0d7d6e10fe9 + 1 + E40880ac-c27b-4cbf-a011-b0d7d6e10fe9 + 1 + Retrieved from "http://en.openei.org/w/index.php?title=Property:OpenEI/UtilityRate/DemandRateStructure/Tier4Rate&oldid=53975

400

SIL rating fire protection equipment  

Science Conference Proceedings (OSTI)

SIL's (Safety Integrity Levels) are used by IEC 61508:1998 [1] to characterise the required functional safety of computer control systems. For example, SIL 4, the highest rating is for fly by wire aircraft and weapons systems and track circuited train ... Keywords: SIL, fire control panels, fire systems

Richard M. Robinson; Kevin J. Anderson

2003-10-01T23:59:59.000Z

Note: This page contains sample records for the topic "beta-gamma dose rates" from the National Library of EnergyBeta (NLEBeta).
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We encourage you to perform a real-time search of NLEBeta
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401

Fast repetition rate (FRR) flasher  

DOE Patents (OSTI)

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.

Kolber, Z.; Falkowski, P.

1997-02-11T23:59:59.000Z

402

Electric Rate Alternatives to Cogeneration  

E-Print Network (OSTI)

This paper discusses electric rate alternatives to cogeneration for the industrial customer and attempts to identify the effects on the utility company, the industrial customer as well as remaining customers. It is written from the perspective of one company and its exposure to cogenerstion within its service territory.

Sandberg, K. R. Jr.

1988-09-01T23:59:59.000Z

403

Instability statistics and mixing rates  

E-Print Network (OSTI)

We claim that looking at probability distributions of \\emph{finite time} largest Lyapunov exponents, and more precisely studying their large deviation properties, yields an extremely powerful technique to get quantitative estimates of polynomial decay rates of time correlations and Poincar\\'e recurrences in the -quite delicate- case of dynamical systems with weak chaotic properties.

Roberto Artuso; Cesar Manchein

2009-06-03T23:59:59.000Z

404

2010FirmRateAdj  

NLE Websites -- All DOE Office Websites (Extended Search)

Firm Peaking Revenue Requirement 320.2 million P-SMPB--ED Composite Rate 33.25 millskWh Firm Demand 7.65kWmo Firm Energy 19.05 millskWh Firm Peaking Demand 6.90kWmo Firm...

405

Energy Management Through Innovative Rates  

E-Print Network (OSTI)

Increased costs and a continuing dependence on uncertain supplies of domestic and foreign energy resources have prompted many companies to focus their attention on energy management. The author explores the potential for achieving a greater measure of energy efficiency in the industrial sector and specific rate design alternatives for doing so.

Williams, M. L.

1982-01-01T23:59:59.000Z

406

Patient-specific dose estimation for pediatric chest CT  

SciTech Connect

Current methods for organ and effective dose estimations in pediatric CT are largely patient generic. Physical phantoms and computer models have only been developed for standard/limited patient sizes at discrete ages (e.g., 0, 1, 5, 10, 15 years old) and do not reflect the variability of patient anatomy and body habitus within the same size/age group. In this investigation, full-body computer models of seven pediatric patients in the same size/protocol group (weight: 11.9-18.2 kg) were created based on the patients' actual multi-detector array CT (MDCT) data. Organs and structures in the scan coverage were individually segmented. Other organs and structures were created by morphing existing adult models (developed from visible human data) to match the framework defined by the segmented organs, referencing the organ volume and anthropometry data in ICRP Publication 89. Organ and effective dose of these patients from a chest MDCT scan protocol (64 slice LightSpeed VCT scanner, 120 kVp, 70 or 75 mA, 0.4 s gantry rotation period, pitch of 1.375, 20 mm beam collimation, and small body scan field-of-view) was calculated using a Monte Carlo program previously developed and validated to simulate radiation transport in the same CT system. The seven patients had normalized effective dose of 3.7-5.3 mSv/100 mAs (coefficient of variation: 10.8%). Normalized lung dose and heart dose were 10.4-12.6 mGy/100 mAs and 11.2-13.3 mGy/100 mAs, respectively. Organ dose variations across the patients were generally small for large organs in the scan coverage (<7%), but large for small organs in the scan coverage (9%-18%) and for partially or indirectly exposed organs (11%-77%). Normalized effective dose correlated weakly with body weight (correlation coefficient: r=-0.80). Normalized lung dose and heart dose correlated strongly with mid-chest equivalent diameter (lung: r=-0.99, heart: r=-0.93); these strong correlation relationships can be used to estimate patient-specific organ dose for any other patient in the same size/protocol group who undergoes the chest scan. In summary, this work reported the first assessment of dose variations across pediatric CT patients in the same size/protocol group due to the variability of patient anatomy and body habitus and provided a previously unavailable method for patient-specific organ dose estimation, which will help in assessing patient risk and optimizing dose reduction strategies, including the development of scan protocols.

Li Xiang; Samei, Ehsan; Segars, W. Paul; Sturgeon, Gregory M.; Colsher, James G.; Frush, Donald P. [Medical Physics Graduate Program, Duke University, Durham, North Carolina 27705 and Department of Radiology, Duke Advanced Imaging Laboratories, Duke University Medical Center, Durham, North Carolina 27705 (United States); Medical Physics Graduate Program, Duke University, Durham, North Carolina 27705 (United States); Department of Radiology, Duke Advanced Imaging Laboratories, Duke University Medical Center, Durham, North Carolina 27705 (United States); Department of Physics, Duke University, Durham, North Carolina 27710 (United States); and Department of Biomedical Engineering, Duke University, Durham, North Carolina 27708 (United States); Medical Physics Graduate Program, Duke University, Durham, North Carolina 27705 and Department of Radiology, Duke Advanced Imaging Laboratories, Duke University Medical Center, Durham, North Carolina 27705 (United States); Department of Radiology, Duke Advanced Imaging Laboratories, Duke University Medical Center, Durham, North Carolina 27705 (United States); Medical Physics Graduate Program, Duke University, Durham, North Carolina 27705 and Global Applied Science Laboratory, GE Healthcare, Waukesha, Wisconsin 53188 (United States); Medical Physics Graduate Program, Duke University, Durham, North Carolina 27705 and Department of Radiology, Division of Pediatric Radiology, Duke University Medical Center, Durham North Carolina 27710 (United States)

2008-12-15T23:59:59.000Z

407

Absorbed dose measurements during routine equine radiographic procedures  

E-Print Network (OSTI)

This study was performed in order to determine absorbed doses from scattered radiation to personnel during routine equine radiographic procedures and to determine if the protective apparel adequately reduced exposure from scattered radiation. Absorbed doses were measured for one month at the Texas A&M University Veterinary Teaching Hospital using Li:Mg,Cu,P thermoluminescent dosimeters (TLDs). All personnel present in the x-ray examination room during eqine radiography were monitored using TLDs placed at: (1) the finger level; (2) the waist level; (3) the eye level; and (4) the forearm level. Absorbed doses ranged from 0.693 ligy to 31.3 tigy per study. The greatest doses were associated with the individual handling the cassette holder, although the individual making the exposures received similar doses due to improper techniques. The individual holding the horse's halter consistently received the lowest dose. Although all doses observed were within acceptable limits for occupational workers, results demonstrated the need for protective apparel to effectively reduce exposures.

Salinas, Leticia Lamar

1996-01-01T23:59:59.000Z

408

Dose Calculation Evolution for Internal Organ Irradiation in Humans  

Science Conference Proceedings (OSTI)

The International Commission of Radiation Units (ICRU) has established through the years, a discrimination system regarding the security levels on the prescription and administration of doses in radiation treatments (Radiotherapy, Brach therapy, Nuclear Medicine). The first level is concerned with the prescription and posterior assurance of dose administration to a point of interest (POI), commonly located at the geometrical center of the region to be treated. In this, the effects of radiation around that POI, is not a priority. The second level refers to the dose specifications in a particular plane inside the patient, mostly the middle plane of the lesion. The dose is calculated to all the structures in that plane regardless if they are tumor or healthy tissue. In this case, the dose is not represented by a point value, but by level curves called 'isodoses' as in a topographic map, so you can assure the level of doses to this particular plane, but it also leave with no information about how this values go thru adjacent planes. This is why the third level is referred to the volumetrical description of doses so these isodoses construct now a volume (named 'cloud') that give us better assurance about tissue irradiation around the volume of the lesion and its margin (sub clinical spread or microscopic illness). This work shows how this evolution has resulted, not only in healthy tissue protection improvement but in a rise of tumor control, quality of life, better treatment tolerance and minimum permanent secuelae.

Jimenez V, Reina A. [Universidad Central de Venezuela, Hospital Domingo Luciani, IVSS, Caracas, 1070 (Venezuela)

2007-10-26T23:59:59.000Z

409

Low Dose Radiation Research Program: 12.5 keV Xray Microbeam Bystander  

NLE Websites -- All DOE Office Websites (Extended Search)

12.5 keV Xray Microbeam Bystander Studies With Human Mammary 12.5 keV Xray Microbeam Bystander Studies With Human Mammary Epithelial Cells and Fibroblasts Authors: E. A. Blakely1, R. I. Schwarz1, A. C. Thompson2, K. A. Bjornstad1, P. Y. Chang1,3 C.J. Rosen1, and D. Sudar1 Institutions: Divisions of 1Life Sciences and 2Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, CA. and 3SRI International, Menlo Park, CA. We are using a novel x-ray Microprobe Beamline at the Advanced Light Source (ALS) at LBNL to investigate bystander effects of low doses in well characterized human mammary epithelial cells (HMEC) and human skin fibroblasts (HSF). The ALS facility is capable of producing a beam of 12.5 keV x-rays with a focussed spot size of __m_ and a wide range of doses and dose-rates. Unlike normal x-ray sources, this beam has a very small background of either low-

410

Detector Photon Response and Absorbed Dose and Their Applications to Rapid Triage Techniques  

E-Print Network (OSTI)

As radiation specialists, one of our primary objectives in the Navy is protecting people and the environment from the effects of ionizing and non-ionizing radiation. Focusing on radiological dispersal devices (RDD) will provide increased personnel protection as well as optimize emergency response assets for the general public. An attack involving an RDD has been of particular concern because it is intended to spread contamination over a wide area and cause massive panic within the general population. A rapid method of triage will be necessary to segregate the unexposed and slightly exposed from those needing immediate medical treatment. Because of the aerosol dispersal of the radioactive material, inhalation of the radioactive material may be the primary exposure route. The primary radionuclides likely to be used in a RDD attack are Co-60, Cs-137, Ir-192, Sr-90 and Am-241. Through the use of a MAX phantom along with a few Simulink MATLAB programs, a good anthropomorphic phantom was created for use in MCNPX simulations that would provide organ doses from internally deposited radionuclides. Ludlum model 44-9 and 44-2 detectors were used to verify the simulated dose from the MCNPX code. Based on the results, acute dose rate limits were developed for emergency response personnel that would assist in patient triage.

Voss, Shannon Prentice

2008-08-01T23:59:59.000Z

411

Peak Dose Assessment for Proposed DOE-PPPO Authorized Limits  

Science Conference Proceedings (OSTI)

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.

DELIS MALDONADO

2012-06-01T23:59:59.000Z

412

Hydrogen Generation Rate Scoping Study of DOW Corning Antifoam Agent  

DOE Green Energy (OSTI)

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.

Crawford, Charles

2005-09-27T23:59:59.000Z

413

Federal Energy Management Program: Water Rate Escalations  

NLE Websites -- All DOE Office Websites (Extended Search)

Rate Rate Escalations to someone by E-mail Share Federal Energy Management Program: Water Rate Escalations on Facebook Tweet about Federal Energy Management Program: Water Rate Escalations on Twitter Bookmark Federal Energy Management Program: Water Rate Escalations on Google Bookmark Federal Energy Management Program: Water Rate Escalations on Delicious Rank Federal Energy Management Program: Water Rate Escalations on Digg Find More places to share Federal Energy Management Program: Water Rate Escalations on AddThis.com... Sustainable Buildings & Campuses Operations & Maintenance Greenhouse Gases Water Efficiency Basics Federal Requirements Best Management Practices Analysis and Evaluation Water Rate Escalations Evaluation Service Contracts Case Studies Resources

414

Molecular Mechanism Underlying Cellular Adaptive Response to Low Dose Radiation  

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Mechanism Underlying Cellular Adaptive Response to Low Dose Radiation Mechanism Underlying Cellular Adaptive Response to Low Dose Radiation Colette A. Sacksteder § , DJ Black ‡ , Heather Smallwood § , David G. Camp II † , and Thomas C. Squier § § Cell Biology and Biochemistry; † Biological Sciences Division Pacific Northwest National Laboratory, Richland WA 99352 ‡ School of Biological Sciences, University of Missouri, Kansas City MO 64110 The goal of this research is to identify the molecular mechanisms by which cells adapt to low dose radiation exposure. Previously we have shown a radiation dependent increase of Calmodulin (CaM) in RAW 264.7 macrophages (RAW). Therefore we hypothesize that CaM and associated signaling complexes are sensors of low-dose radiation, resulting in alterations in energy metabolism and gene expression. The ultimate experimental goal

415

Low Dose Radiation Research Program: Biologically Based Analysis of Lung  

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Biologically Based Analysis of Lung Cancer Incidence in a Large Biologically Based Analysis of Lung Cancer Incidence in a Large Canadian Occupational Cohort with Low-LET Low-dose Radiation Exposure, and Comparison with Japanese Atomic Bomb Survivors. Authors: W.D. Hazelton, D. Krewski, S.H. Moolgavkar Lung cancer incidence is analyzed in a large Canadian National Dose Registry (CNDR) cohort with individual annual dosimetry for low-dose occupational exposure to gamma and tritium radiation using several types of multistage models. The primary analysis utilizes the two-stage clonal expansion model (TSCE), with sensitivity analyses using extensions of this model incorporating additional stages. Characteristic and distinct temporal patterns of risk are found for dose-response affecting early, middle, or late stages of carcinogenesis, e.g., initiation with one or more stages,

416

Low Dose Radiation Research Program: Research Highlights - Health Physics  

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Health Physics Special Issue Features Contributions by Low Dose Health Physics Special Issue Features Contributions by Low Dose Investigators Health Physics The March 2011 special issue of Health Physics highlights the Victor Bond Workshop held May 2-5, 2010, in Richland, Wash. The workshop honored the late Dr. Victor (Vic) Bond for his lifetime achievement in the radiation sciences. Dr. Bond's research resulted in numerous influential scientific papers that contributed greatly to the understanding of radiation effects in biological systems. The workshop attracted internationally recognized experts in biophysics, experimental radiation biology, epidemiology, and risk assessment to discuss issues of low-dose risk. Participants included current and previously funded U.S. Department of Energy Low Dose Radiation Research

417

Genetic profiling of lymphoblastoid cell lines sensitive to low dose  

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profiling of lymphoblastoid cell lines sensitive to low dose profiling of lymphoblastoid cell lines sensitive to low dose radiation David Rocke University of California Davis Abstract Previous study from our laboratory has identified pathways associated with low dose ionizing radiation (LDIR) in vivo that is consistent across individuals. Furthermore, gene expression patterns have revealed genetic variation between individuals, which may play a role in individual sensitivity to LDIR. The aim is to evaluate mi