Powered by Deep Web Technologies
Note: This page contains sample records for the topic "radiation dose equivalent" 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.


1

Biological equivalent dose studies for dose escalation in the stereotactic synchrotron radiation therapy clinical trials  

E-Print Network (OSTI)

at the European Synchrotron Radiation Facility ESRF . To estimate the possible risks, the doses receivedBiological equivalent dose studies for dose escalation in the stereotactic synchrotron radiation technique a radiation dose enhancement specific to the tumor is obtained. The tumor is loaded with a high

Boyer, Edmond

2

Estimating Radiation Risk from Total Effective Dose Equivalent...  

National Nuclear Security Administration (NNSA)

and UNSCEAR 1988 in Radiation Risk Assessment - Lifetime Total Cancer Mortality Risk Estimates at Low Doses and Low Dose Rates for Low-LET Radiation, Committee on Interagency...

3

Modeling proton intensity gradients and radiation dose equivalents in the inner  

E-Print Network (OSTI)

Modeling proton intensity gradients and radiation dose equivalents in the inner heliosphere using a significant radiation hazard for manned and unmanned interplanetary (IP) space missions. In order to estimate intensities, event fluences, and radiation dose equivalents of 27­31 May 2003 SEP events at eight different

Pringle, James "Jamie"

4

Influence of organs in the ICRP's remainder on effective dose equivalent computed for diagnostic radiation exposures  

SciTech Connect

The ICRP effective dose equivalent has been compared with a weighted dose equivalent, computed by treating the entire remainder instead of the sample of five remainder organs in the ICRP method as uniformly radiosensitive, for dose distributions from three common diagnostic exposures: chest, dental full-mouth and dental panoramic. Complete dose distributions were computed by a Monte Carlo model. In all three cases the effective dose equivalent was greater than the weighted dose equivalent. The difference was only 20% for the chest exam but was more than fivefold for both dental exposures. Dose distributions for the dental exposures were less homogeneous than for the chest examination. Selection of organs to be included in the remainder markedly affects the effective dose equivalent. In the case of highly inhomogeneous dose distributions, the effective dose equivalent probably significantly over-estimates radiation detriment.

Gibbs, S.J.

1989-04-01T23:59:59.000Z

5

Improvement of the equivalent sphere model for better estimates of skin or eye dose in space radiation environments  

E-Print Network (OSTI)

sphere Radiation transport a b s t r a c t It is often useful to get a quick estimate of the dose or dose drastically improves the accuracy of the estimates of dose and dose equivalent in space radiation environmentsImprovement of the equivalent sphere model for better estimates of skin or eye dose in space

Lin, Zi-wei

6

Neutron dose equivalent meter  

DOE Patents (OSTI)

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

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

1996-01-01T23:59:59.000Z

7

RADIATION PROTECTION KEYWORDS: equivalent sphere  

E-Print Network (OSTI)

RADIATION PROTECTION KEYWORDS: equivalent sphere model, space radiation, organ dose IMPROVEMENT- alent sphere is used to represent the organ for a fast estimate of the organ dose. It has been found ~ESM! with an organ- specific constant radius parameter is used for fast estimates of the organ dose

Lin, Zi-wei

8

Using Generalized Equivalent Uniform Dose Atlases to Combine and Analyze Prospective Dosimetric and Radiation Pneumonitis Data From 2 Non-Small Cell Lung Cancer Dose Escalation Protocols  

SciTech Connect

Purpose: To demonstrate the use of generalized equivalent uniform dose (gEUD) atlas for data pooling in radiation pneumonitis (RP) modeling, to determine the dependence of RP on gEUD, to study the consistency between data sets, and to verify the increased statistical power of the combination. Methods and Materials: Patients enrolled in prospective phase I/II dose escalation studies of radiation therapy of non-small cell lung cancer at Memorial Sloan-Kettering Cancer Center (MSKCC) (78 pts) and the Netherlands Cancer Institute (NKI) (86 pts) were included; 10 (13%) and 14 (17%) experienced RP requiring steroids (RPS) within 6 months after treatment. gEUD was calculated from dose-volume histograms. Atlases for each data set were created using 1-Gy steps from exact gEUDs and RPS data. The Lyman-Kutcher-Burman model was fit to the atlas and exact gEUD data. Heterogeneity and inconsistency statistics for the fitted parameters were computed. gEUD maps of the probability of RPS rate {>=}20% were plotted. Results: The 2 data sets were homogeneous and consistent. The best fit values of the volume effect parameter a were small, with upper 95% confidence limit around 1.0 in the joint data. The likelihood profiles around the best fit a values were flat in all cases, making determination of the best fit a weak. All confidence intervals (CIs) were narrower in the joint than in the individual data sets. The minimum P value for correlations of gEUD with RPS in the joint data was .002, compared with P=.01 and .05 for MSKCC and NKI data sets, respectively. gEUD maps showed that at small a, RPS risk increases with gEUD. Conclusions: The atlas can be used to combine gEUD and RPS information from different institutions and model gEUD dependence of RPS. RPS has a large volume effect with the mean dose model barely included in the 95% CI. Data pooling increased statistical power.

Liu Fan; Yorke, Ellen D. [Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, New York (United States)] [Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Belderbos, Jose S.A.; Borst, Gerben R. [The Netherlands Cancer Institute, Antoni Van Leeuwenhoek Hospital, Amsterdam (Netherlands)] [The Netherlands Cancer Institute, Antoni Van Leeuwenhoek Hospital, Amsterdam (Netherlands); Rosenzweig, Kenneth E. [Mount Sinai School of Medicine, New York, New York (United States)] [Mount Sinai School of Medicine, New York, New York (United States); Lebesque, Joos V. [The Netherlands Cancer Institute, Antoni Van Leeuwenhoek Hospital, Amsterdam (Netherlands)] [The Netherlands Cancer Institute, Antoni Van Leeuwenhoek Hospital, Amsterdam (Netherlands); Jackson, Andrew, E-mail: jacksona@mskcc.org [Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, New York (United States)] [Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, New York (United States)

2013-01-01T23:59:59.000Z

9

Radiation Dose Estimates from  

E-Print Network (OSTI)

Summary: Radiation Dose Estimates from Hanford Radioactive Material Releases to the Air- tantly, what radiation dose people may have received. An independent Technical Steering Panel (TSP, additionalProjectworkcouldresultin revisions of these dose estimates. April 21, 1994 Companion

10

Dose-equivalent neutron dosimeter  

DOE Patents (OSTI)

A neutron dosimeter is disclosed which provides a single measurement indicating the amount of potential biological damage resulting from the neutron exposure of the wearer, for a wide range of neutron energies. The dosimeter includes a detecting sheet of track etch detecting material such as a carbonate plastic, for detecting higher energy neutrons, and a radiator layer contaning conversion material such as /sup 6/Li and /sup 10/B lying adjacent to the detecting sheet for converting moderate energy neutrons to alpha particles that produce tracks in the adjacent detecting sheet.

Griffith, R.V.; Hankins, D.E.; Tomasino, L.; Gomaa, M.A.M.

1981-01-07T23:59:59.000Z

11

An assessment of current and proposed methodologies for estimating effective dose equivalent from non-uniform external photon radiation  

E-Print Network (OSTI)

voluntarily from various nuclear power plants throughout the United States were used. The data were analyzed with respect to the current practice of assigning the highest whole body multibadging dosimeter reading as the dose of record pursuant to 10 CFR (Code...

Hay, Michael Charles

2012-06-07T23:59:59.000Z

12

Personal Dose Equivalent Conversion Coefficients For Photons To 1 GEV  

SciTech Connect

The personal dose equivalent, H{sub p}(d), is the quantity recommended by the International Commission on Radiation Units and Measurements (ICRU) to be used as an approximation of the protection quantity Effective Dose when performing personal dosemeter calibrations. The personal dose equivalent can be defined for any location and depth within the body. Typically, the location of interest is the trunk where personal dosemeters are usually worn and in this instance a suitable approximation is a 30 cm X 30 cm X 15 cm slab-type phantom. For this condition the personal dose equivalent is denoted as H{sub p,slab}(d) and the depths, d, are taken to be 0.007 cm for non-penetrating and 1 cm for penetrating radiation. In operational radiation protection a third depth, 0.3 cm, is used to approximate the dose to the lens of the eye. A number of conversion coefficients for photons are available for incident energies up to several MeV, however, data to higher energies are limited. In this work conversion coefficients up to 1 GeV have been calculated for H{sub p,slab}(10) and H{sub p,slab}(3) using both the kerma approximation and by tracking secondary charged particles. For H{sub p}(0.07) the conversion coefficients were calculated, but only to 10 MeV due to computational limitations. Additionally, conversions from air kerma to H{sub p,slab}(d) have been determined and are reported. The conversion coefficients were determined for discrete incident energies, but analytical fits of the coefficients over the energy range are provided. Since the inclusion of air can influence the production of secondary charged particles incident on the face of the phantom conversion coefficients have been determined both in vacuo and with the source and slab immersed within a sphere in air. The conversion coefficients for the personal dose equivalent are compared to the appropriate protection quantity, calculated according to the recommendations of the latest International Commission on Radiological Protection (ICRP) guidance.

Veinot, K. G.; Hertel, N. E.

2010-09-27T23:59:59.000Z

13

Development of an optimal anisotropic responding (OAR) dosimeter for two-dosimeter dosimetry for better estimation of effective dose equivalent (He) and the impact of dosimeter misposition on estimating effective dose equivalent using isotropic dosimeters  

E-Print Network (OSTI)

A single dosimeter is commonly worn on a radiation worker's chest to monitor radiation exposure. However, when a radiation worker is exposed to a posterior photon beam, effective dose equivalent (HE) can be severely underestimated using a single...

Han, Hsiang-Jung

2012-06-07T23:59:59.000Z

14

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,

15

E-Print Network 3.0 - accumulated radiation dose Sample Search...  

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

. At the end, this seminar concentrates on the dose contributions of naturally occurring ionizing radiation... particles. - The equivalent dose, HT, which takes into account...

16

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

17

7 - Estimation of Radiation Doses  

Science Journals Connector (OSTI)

Abstract Radiation doses to the Japanese population from inhalation of contaminated air, external irradiation, terrestrial and marine food contamination are estimated and compared with other sources of anthropogenic (global fallout, Chernobyl accident), natural (radionuclides in food, cosmic radiation) and medical applications (X-ray tests, CT-tests, etc.) of ionizing radiation. The estimated doses from inhalation, ingestion of terrestrial and marine food, and radiation exposure from radioactive clouds and deposited radionuclides were generally below the levels which could cause health damage of the Japanese population, as well as of the world population. The estimated total radiation doses to fish and shellfish in coastal waters during the largest radionuclide releases were by a factor of 10 lower than the baseline safe level postulated for the marine organisms, therefore no harmful effects are expected for the marine ecosystem as well.

Pavel P. Povinec; Katsumi Hirose; Michio Aoyama

2013-01-01T23:59:59.000Z

18

Effective dose equivalent to the operator in intra-oral dental radiography  

SciTech Connect

The effective dose equivalent to the operator in intra-oral dental radiography has been determined. The exposure from a bitewing radiograph and periapical views of the left maxillary incisors and first molar was measured at nine heights and 16 positions, all 1 m from the patient. The effective dose equivalent was determined using data from ICRP 51 (International Commission on Radiological Protection: Data for Use in Protection Against External Radiation). The values presented are related to an exposure of 1 C kg-1 (3876 R) measured free in air at the tube-end. They thus constitute ratios which are not influenced by the sensitivity of the film or other detector used and form standard tables which permit the calculation of the effective dose equivalent in clinical situations.

de Haan, R.A.; van Aken, J. (Utrecht Univ., (The Netherlands))

1990-08-01T23:59:59.000Z

19

Measurement of neutron dose equivalent outside and inside of the treatment vault of GRID therapy  

SciTech Connect

Purpose: To evaluate the neutron and photon dose equivalent rates at the treatment vault entrance (H{sub n,D} and H{sub G}), and to study the secondary radiation to the patient in GRID therapy. The radiation activation on the grid was studied.Methods: A Varian Clinac 23EX accelerator was working at 18 MV mode with a grid manufactured by .decimal, Inc. The H{sub n,D} and H{sub G} were measured using an AnderssonBraun neutron REM meter, and a Geiger Mller counter. The radiation activation on the grid was measured after the irradiation with an ion chamber ?-ray survey meter. The secondary radiation dose equivalent to patient was evaluated by etched track detectors and OSL detectors on a RANDO{sup } phantom.Results: Within the measurement uncertainty, there is no significant difference between the H{sub n,D} and H{sub G} with and without a grid. However, the neutron dose equivalent to the patient with the grid is, on average, 35.3% lower than that without the grid when using the same field size and the same amount of monitor unit. The photon dose equivalent to the patient with the grid is, on average, 44.9% lower. The measured average half-life of the radiation activation in the grid is 12.0 (0.9) min. The activation can be categorized into a fast decay component and a slow decay component with half-lives of 3.4 (1.6) min and 15.3 (4.0) min, respectively. There was no detectable radioactive contamination found on the surface of the grid through a wipe test.Conclusions: This work indicates that there is no significant change of the H{sub n,D} and H{sub G} in GRID therapy, compared with a conventional external beam therapy. However, the neutron and scattered photon dose equivalent to the patient decrease dramatically with the grid and can be clinical irrelevant. Meanwhile, the users of a grid should be aware of the possible high dose to the radiation worker from the radiation activation on the surface of the grid. A delay in handling the grid after the beam delivery is suggested.

Wang, Xudong; Charlton, Michael A.; Esquivel, Carlos; Eng, Tony Y.; Li, Ying; Papanikolaou, Nikos [University of Texas Health Science Center, San Antonio, Texas 78229 (United States)] [University of Texas Health Science Center, San Antonio, Texas 78229 (United States)

2013-09-15T23:59:59.000Z

20

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

Note: This page contains sample records for the topic "radiation dose equivalent" 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

Estimates of internal-dose equivalent from inhalation and ingestion of selected radionuclides  

SciTech Connect

This report presents internal radiation dose conversion factors for radionuclides of interest in environmental assessments of nuclear fuel cycles. This volume provides an updated summary of estimates of committed dose equivalent for radionuclides considered in three previous Oak Ridge National Laboratory (ORNL) reports. Intakes by inhalation and ingestion are considered. The International Commission on Radiological Protection (ICRP) Task Group Lung Model has been used to simulate the deposition and retention of particulate matter in the respiratory tract. Results corresponding to activity median aerodynamic diameters (AMAD) of 0.3, 1.0, and 5.0 ..mu..m are given. The gastorintestinal (GI) tract has been represented by a four-segment catenary model with exponential transfer of radioactivity from one segment to the next. Retention of radionuclides in systemic organs is characterized by linear combinations of decaying exponential functions, recommended in ICRP Publication 30. The first-year annual dose rate, maximum annual dose rate, and fifty-year dose commitment per microcurie intake of each radionuclide is given for selected target organs and the effective dose equivalent. These estimates include contributions from specified source organs plus the systemic activity residing in the rest of the body; cross irradiation due to penetrating radiations has been incorporated into these estimates. 15 references.

Dunning, D.E.

1982-01-01T23:59:59.000Z

22

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

23

Total effective dose equivalent associated with fixed uranium surface contamination  

SciTech Connect

This report provides the technical basis for establishing a uranium fixed-contamination action level, a fixed uranium surface contamination level exceeding the total radioactivity values of Appendix D of Title 10, Code of Federal Regulations, part 835 (10CFR835), but below which the monitoring, posting, and control requirements for Radiological Areas are not required for the area of the contamination. An area of fixed uranium contamination between 1,000 dpm/100 cm{sup 2} and that level corresponding to an annual total effective dose equivalent (TEDE) of 100 mrem requires only routine monitoring, posting to alert personnel of the contamination, and administrative control. The more extensive requirements for monitoring, posting, and control designated by 10CFR835 for Radiological Areas do not have to be applied for these intermediate fixed-contamination levels.

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

1997-04-01T23:59:59.000Z

24

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

25

Low Dose Radiation Program: Radiation Biology and the Radiation Research  

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

Biology and the Radiation Research Program Biology and the Radiation Research Program The Department of Energy (DOE) and its predecessor organizations, Energy Research and Development Agency (ERDA) and Atomic Energy Commission (AEC), always have been concerned about the health effects of ionizing radiation. Extensive research has been conducted under their sponsorship at all levels of biological organization from molecules to man. Over the past 60 years, studies using every type of radiation source have included exposure to both external radiation sources and to internally deposited radioactive materials. These exposures used different dose patterns and distributions delivered over a wide range of experimental times. This extensive research provided the basis for the new Low Dose Radiation Research Program, linking

26

Estimated Ultraviolet Radiation Doses in Wetlands in  

E-Print Network (OSTI)

Estimated Ultraviolet Radiation Doses in Wetlands in Six National Parks Stephen A. Diamond,1 ABSTRACT Ultraviolet-B radiation (UV-B, 280­320-nm wave- lengths) doses were estimated for 1024 wetlands of vegetative features, and quantification of DOC concentration and spectral absorbance. UV-B dose estimates

Knapp, Roland

27

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

28

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

29

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

30

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,

31

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

32

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,

33

Low Dose Radiation Research Program: Low Dose Radiation Effects in  

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

Radiation Effects in Differentiating Human Lens Cells Radiation Effects in Differentiating Human Lens Cells E.A. Blakely1, M.P. McNamara1, P.Y. Chang1, K.A. Bjornstad1, D. Sudar1, and A.C. Thompson2 1Life Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California; 2Advanced Light Source Division, Lawrence Berkeley National Laboratory, Berkeley, California. Introduction The human lens is one of the most radiosensitive organs of the body. Cataract, the opacification of the lens, is a late-appearing response to radiation damage. There are few data available on the late radiation effects of exposure in space flight to charged particle beams, the most prevalent of which are protons. Basic research in this area is needed to integrate the responses of both critical and other representative tissues

34

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

35

Radiation dose in dental radiology  

Science Journals Connector (OSTI)

...The aim of this study was to compare radiation exposure in panoramic radiography (PR), dental CT, and digital volume tomography (DVT) ... at appropriate locations were exposed as in a dental examination. In PR...

M. Cohnen; J. Kemper; O. Mbes; J. Pawelzik; U. Mdder

2002-03-01T23:59:59.000Z

36

RADIATION DOSE FROM CIGARETTE TOBACCO  

Science Journals Connector (OSTI)

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 226 Ra and 210 Pb of the uranium series and 228 Ra of the thorium series and/or man?made produced radionuclides such as 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 226 Ra varied from 42.5 to 178.6?? Sv ? y ?1 (average 79.7?? Sv ? y ?1 ) while for 228 Ra from 19.3 to 116.0?? Sv ? y ?1 (average 67.1?? Sv ? y ?1 ) and for 210 Pb from 47.0 to 134.9?? Sv ? y ?1 (average 104.7?? Sv ? y ?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?? Sv ? y ?1 (average 251.5?? Sv ? y ?1 ). The annual effective dose from 137 Cs of Chernobyl origin was three orders of magnitude lower as it varied from 70.4 to 410.4? nSv ? y ?1 (average 199.3? nSv ? y ?1 ).

C. Papastefanou

2008-01-01T23:59:59.000Z

37

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

38

Functional proteomic pattern identification under low dose ionizing radiation  

Science Journals Connector (OSTI)

Objective: High dose radiation has been well known for increasing the risk of carcinogenesis. However, the understanding of biological effects of low dose radiation is limited. Low dose radiation is reported to affect several signaling pathways including ... Keywords: Feature selection, Jumping emerging identification, Low dose radiation, Proteomic signaling patterns

Young Bun Kim; Chin-Rang Yang; Jean Gao

2010-07-01T23:59:59.000Z

39

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

40

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

E-Print Network (OSTI)

. Brenner* Abstract--There is strong evidence that ionizing radiation increases cancer risks at high doses. There exists a range of high radiation doses which demonstra- bly increase cancer risks, and a lower dose rangePaper EXTRAPOLATING RADIATION-INDUCED CANCER RISKS FROM LOW DOSES TO VERY LOW DOSES David J

Brenner, David Jonathan

Note: This page contains sample records for the topic "radiation dose equivalent" 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

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

SciTech Connect

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

Traub, Richard J.

2010-03-26T23:59:59.000Z

42

76Radiation Dose and Dose Rate Radiation is measured in two  

E-Print Network (OSTI)

Seiverts per year. Hasty reports about the devastating Japan 2011 nuclear power plant radiation leakages have by Concorde, what are the total radiation doses for a passenger in each case? Problem 3 - The Japan 2011 earthquake damaged several nuclear reactors, causing radiation leakage across northern Japan. On March 22

43

PET/CT-guided Interventions: Personnel Radiation Dose  

SciTech Connect

PurposeTo quantify radiation exposure to the primary operator and staff during PET/CT-guided interventional procedures.MethodsIn this prospective study, 12 patients underwent PET/CT-guided interventions over a 6 month period. Radiation exposure was measured for the primary operator, the radiology technologist, and the nurse anesthetist by means of optically stimulated luminescence dosimeters. Radiation exposure was correlated with the procedure time and the use of in-room image guidance (CT fluoroscopy or ultrasound).ResultsThe median effective dose was 0.02 (range 0-0.13) mSv for the primary operator, 0.01 (range 0-0.05) mSv for the nurse anesthetist, and 0.02 (range 0-0.05) mSv for the radiology technologist. The median extremity dose equivalent for the operator was 0.05 (range 0-0.62) mSv. Radiation exposure correlated with procedure duration and with the use of in-room image guidance. The median operator effective dose for the procedure was 0.015 mSv when conventional biopsy mode CT was used, compared to 0.06 mSv for in-room image guidance, although this did not achieve statistical significance as a result of the small sample size (p = 0.06).ConclusionThe operator dose from PET/CT-guided procedures is not significantly different than typical doses from fluoroscopically guided procedures. The major determinant of radiation exposure to the operator from PET/CT-guided interventional procedures is time spent in close proximity to the patient.

Ryan, E. Ronan, E-mail: ronan@ronanryan.com; Thornton, Raymond; Sofocleous, Constantinos T.; Erinjeri, Joseph P. [Memorial Sloan-Kettering Cancer Center, Department of Radiology (United States); Hsu, Meier [Memorial Sloan-Kettering Cancer Center, Department of Epidemiology and Biostatistics (United States); Quinn, Brian; Dauer, Lawrence T. [Memorial Sloan-Kettering Cancer Center, Department of Medical Physics (United States); Solomon, Stephen B. [Memorial Sloan-Kettering Cancer Center, Department of Radiology (United States)

2013-08-01T23:59:59.000Z

44

Low Dose Radiation Research Program: DOE Lowdose Radiation Program Workshop  

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

Using a Low LET Electron Microbeam to Investigate Non-Targeted Using a Low LET Electron Microbeam to Investigate Non-Targeted Effects of Low Dose Radiation. Authors: William F. Morgan1 and Marianne B. Sowa2 Institutions: 1Radiation Oncology Research Laboratory, University of Maryland, Baltimore MD 21201 2 Chemical Structure and Dynamics, Pacific Northwest National Laboratory, Richland WA 99352 We have recently installed a low LET electron microbeam that generates energetic electrons to mimic radiation damage from gamma and x-ray sources. It has been designed such that high-energy electrons deposit energy in a pre-selected subset of cells leaving neighboring cells unirradiated (Figure 1). In this way it is possible to examine non-targeted effects associated with low dose radiation exposure including induced genomic instability and

45

The leaded apron revisited: does it reduce gonadal radiation dose in dental radiology  

SciTech Connect

A tissue-equivalent anthropomorphic human phantom was used with a lithium fluoride thermoluminescent dosimetry system to evaluate the radiation absorbed dose to the ovarian and testicular region during dental radiologic procedures. Measurements were made with and without personal lead shielding devices consisting of thyroid collar and apron of 0.25 mm lead thickness equivalence. The radiation absorbed dose with or without lead shielding did not differ significantly from control dosimeters in vertex occlusal and periapical views (p greater than 0.05). Personal lead shielding devices did reduce gonadal dose in the case of accidental exposure (p less than 0.05). A leaded apron of 0.25 mm lead thickness equivalent was permeable to radiation in direct exposure testing.

Wood, R.E.; Harris, A.M.; van der Merwe, E.J.; Nortje, C.J. (Ontario Cancer Institute, Princess Margaret Hospital, Toronto (Canada))

1991-05-01T23:59:59.000Z

46

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

47

Extended range radiation dose-rate monitor  

DOE Patents (OSTI)

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

Valentine, Kenneth H. (Knoxville, TN)

1988-01-01T23:59:59.000Z

48

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.

49

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

50

Oligonucleotide microarray analysis of low-dose ionizing radiation exposure  

Science Journals Connector (OSTI)

...health risk due to low-dose ionizing radiation is still debated. Functional...pathways that are induced by ionizing irradiation (IR...transcriptionally regulated by low-dose IR in occupationally...and showed different ranges of accumulated doses...

Paola Silingardi; Elena Morandi; Cinzia Severini; Daniele Quercioli; Monica Vaccari; Wolfango Horn; Maria Concetta Nucci; Vittorio Lodi; Francesco Violante; Sandro Grilli; and Annmaria Colacci

2007-05-01T23:59:59.000Z

51

Cell cycle responses to low-dose ionizing radiation.  

Science Journals Connector (OSTI)

...47, 2006] 5178 Low-dose hyper-radiosensitivity...radiosensitivity of cells to doses of ionizing radiation less than 0.5 Gy...connection between low-dose HRS survival, Ataxia...the low dose radiation range (0-1 Gy). MR4 cells...

Sarah A. Krueger; George D. Wilson; Michael C. Joiner; and Brian Marples

2006-04-15T23:59:59.000Z

52

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

53

Reduction of radiation dose to radiosensitive organs and its tradeoff with image quality in Computed Tomography  

E-Print Network (OSTI)

Trimester Fetal Radiation Dose Estimation in 16-MDCT Withoutsimulations for radiation dose estimations discussed in thisspecific radiation dose and cancer risk estimation in CT:

Zhang, Di

2012-01-01T23:59:59.000Z

54

Estimating Radiation Risk from Total Effective Dose Equivalent...  

National Nuclear Security Administration (NNSA)

0CTc itt 0 Tw (an) Tj 10.3 0 Tw (an) Tj 10.3 0 Tw (an) Tj 10.3 a ( )75 Tw5ndj 5.25 0 TD F1 10.5 Tf -0.3 33twithsj 24 0 .75059 0 TD(FactorsTw ( 32 ) Tj 5.25 0 TD F1 10.5 Tf...

55

We can do better than effective dose for estimating or comparing low-dose radiation risks  

E-Print Network (OSTI)

We can do better than effective dose for estimating or comparing low-dose radiation risks D of exposure to different radiation fields. More commonly these days, it is used to estimate or compare radi. Keywords: Low dose risk estimation; Effective dose; Flawed definition; Effective risk 1. INTRODUCTION

Brenner, David Jonathan

56

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

57

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

58

Measurements of neutron dose equivalent for a proton therapy center using uniform scanning proton beams  

SciTech Connect

Purpose: Neutron exposure is of concern in proton therapy, and varies with beam delivery technique, nozzle design, and treatment conditions. Uniform scanning is an emerging treatment technique in proton therapy, but neutron exposure for this technique has not been fully studied. The purpose of this study is to investigate the neutron dose equivalent per therapeutic dose, H/D, under various treatment conditions for uniform scanning beams employed at our proton therapy center. Methods: Using a wide energy neutron dose equivalent detector (SWENDI-II, ThermoScientific, MA), the authors measured H/D at 50 cm lateral to the isocenter as a function of proton range, modulation width, beam scanning area, collimated field size, and snout position. They also studied the influence of other factors on neutron dose equivalent, such as aperture material, the presence of a compensator, and measurement locations. They measured H/D for various treatment sites using patient-specific treatment parameters. Finally, they compared H/D values for various beam delivery techniques at various facilities under similar conditions. Results: H/D increased rapidly with proton range and modulation width, varying from about 0.2 mSv/Gy for a 5 cm range and 2 cm modulation width beam to 2.7 mSv/Gy for a 30 cm range and 30 cm modulation width beam when 18 Multiplication-Sign 18 cm{sup 2} uniform scanning beams were used. H/D increased linearly with the beam scanning area, and decreased slowly with aperture size and snout retraction. The presence of a compensator reduced the H/D slightly compared with that without a compensator present. Aperture material and compensator material also have an influence on neutron dose equivalent, but the influence is relatively small. H/D varied from about 0.5 mSv/Gy for a brain tumor treatment to about 3.5 mSv/Gy for a pelvic case. Conclusions: This study presents H/D as a function of various treatment parameters for uniform scanning proton beams. For similar treatment conditions, the H/D value per uncollimated beam size for uniform scanning beams was slightly lower than that from a passive scattering beam and higher than that from a pencil beam scanning beam, within a factor of 2. Minimizing beam scanning area could effectively reduce neutron dose equivalent for uniform scanning beams, down to the level close to pencil beam scanning.

Zheng Yuanshui; Liu Yaxi; Zeidan, Omar; Schreuder, Andries Niek; Keole, Sameer [ProCure Proton Therapy Center, 5901 West Memorial Road, Oklahoma City, Oklahoma 73142 (United States); INTEGRIS Cancer Insititute, 5911 West Memorial Road, Oklahoma City, Oklahoma 73142 (United States); ProCure Proton Therapy Center, 5901 West Memorial Road, Oklahoma City, Oklahoma 73142 (United States); ProCure Treatment Centers, 420 North Walnut Street, Bloomington, Indiana 47404 (United States); ProCure Proton Therapy Center, 5901 West Memorial Road, Oklahoma City, Oklahoma 73142 (United States)

2012-06-15T23:59:59.000Z

59

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

60

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

Note: This page contains sample records for the topic "radiation dose equivalent" 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.


61

RADIATION EXPOSURE DURING PAEDIATRIC CT IN SUDAN: CT DOSE, ORGAN AND EFFECTIVE DOSES  

Science Journals Connector (OSTI)

......research-article Paper RADIATION EXPOSURE DURING PAEDIATRIC...Energy Commission, Radiation Safety Institute, PO Box 3001...assess the magnitude of radiation exposure during paediatric...CT-Expo 2.1 dosimetry software. Doses were evaluated......

I. I. Suliman; H. M. Khamis; T. H. Ombada; K. Alzimami; M. Alkhorayef; A. Sulieman

2014-11-01T23:59:59.000Z

62

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

63

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

64

Molecular signatures of low dose radiation exposure in human subjects  

Science Journals Connector (OSTI)

...Molecular signatures of low dose radiation exposure in human subjects...Volume 46, 2005] 3096 Low dose ionizing radiation (LDIR) in the 1-10 cGy range has largely unknown biological...the effect and risk at low dose by extrapolation from measured...

Zelanna Goldberg; Chad W. Schwietert; Maggie Isbell; Joerg Lehmann; Robin Stern; Christine Hartmann Siantar; and David M. Rocke

2005-05-01T23:59:59.000Z

65

Superiority of Equivalent Uniform Dose (EUD)-Based Optimization for Breast and Chest Wall  

SciTech Connect

We investigate whether IMRT optimization based on generalized equivalent uniform dose (gEUD) objectives for organs at risk (OAR) results in superior dosimetric outcomes when compared with multiple dose-volume (DV)-based objectives plans for patients with intact breast and postmastectomy chest wall (CW) cancer. Four separate IMRT plans were prepared for each of the breast and CW cases (10 patients). The first three plans used our standard in-house, physician-selected, DV objectives (phys-plan); gEUD-based objectives for the OARs (gEUD-plan); and multiple, 'very stringent,' DV objectives for each OAR and PTV (DV-plan), respectively. The fourth plan was only beam-fluence optimized (FO-plan), without segmentation, which used the same objectives as in the DV-plan. The latter plan was to be used as an 'optimum' benchmark without the effects of the segmentation for deliverability. Dosimetric quantities, such as V{sub 20Gy} for the ipsilateral lung and mean dose (D{sub mean}) for heart, contralateral breast, and contralateral lung were used to evaluate the results. For all patients in this study, we have seen that the gEUD-based plans allow greater sparing of the OARs while maintaining equivalent target coverage. The average ipsilateral lung V{sub 20Gy} reduced from 22 {+-} 4.4% for the FO-plan to 18 {+-} 3% for the gEUD-plan. All other dosimetric quantities shifted towards lower doses for the gEUD-plan. gEUD-based optimization can be used to search for plans of different DVHs with the same gEUDs. The use of gEUD allows selective optimization and reduction of the dose for each OAR and results in a truly individualized treatment plan.

Mihailidis, Dimitris N. [Charleston Radiation Therapy Consultants, Charleston, WV (United States)], E-mail: Dimitris@charlestonradiation.com; Plants, Brian; Farinash, Lloyd; Harmon, Michael; Whaley, Lewis; Raja, Prem; Tomara, Pelagia [Charleston Radiation Therapy Consultants, Charleston, WV (United States)

2010-04-01T23:59:59.000Z

66

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

67

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

68

Calculation of extremity neutron fluence-to-dose equivalent conversion factors  

E-Print Network (OSTI)

) Figure 4. Comparison of NCRP 38 and Siebert and Schuhmacher quality factors. Table 2. PNNL dose equivalent averaged quality factors (Q). * Phantom Finger Wrist 30 cm ICRU sphere Composition PMMA PMMA Tissue-and-bone Tissue-and-bone PMMA PMMA... Tissue-and-bone Tissue-and-bone PM MA PMMA (???) 'Adapted from reference 53. Source Bare Cf Moderated Cf Bare Cf Moderated Cf Bare Cf Moderated Cf Bare Cf Moderated Cf Bare Cf Moderated Cf 9. 2 9. 7 9. 2 9. 7 9. 4 9. 7 9. 4 9. 7 10...

Wood-Zika, Annmarie Ruth

1997-01-01T23:59:59.000Z

69

Equivalent isotropic scattering formulation for transient short-pulse radiative transfer in anisotropic  

E-Print Network (OSTI)

of the transient short-pulse radiation transport through forward and backward anisotropic scattering planar media time-resolved transmittance.13­15 The complete transient radiative transfer equation has been conEquivalent isotropic scattering formulation for transient short-pulse radiative transfer

Guo, Zhixiong "James"

70

Estimation of neutron-equivalent dose in organs of patients undergoing radiotherapy by the use of a novel online digital detector  

Science Journals Connector (OSTI)

Neutron peripheral contamination in patients undergoing high-energy photon radiotherapy is considered as a risk factor for secondary cancer induction. Organ-specific neutron-equivalent dose estimation is therefore essential for a reasonable assessment of these associated risks. This work aimed to develop a method to estimate neutron-equivalent doses in multiple organs of radiotherapy patients. The method involved the convolution, at 16 reference points in an anthropomorphic phantom, of the normalized Monte Carlo neutron fluence energy spectra with the kerma and energy-dependent radiation weighting factor. This was then scaled with the total neutron fluence measured with passive detectors, at the same reference points, in order to obtain the equivalent doses in organs. The latter were correlated with the readings of a neutron digital detector located inside the treatment room during phantom irradiation. This digital detector, designed and developed by our group, integrates the thermal neutron fluence. The correlation model, applied to the digital detector readings during patient irradiation, enables the online estimation of neutron-equivalent doses in organs. The model takes into account the specific irradiation site, the field parameters (energy, field size, angle incidence, etc) and the installation (linac and bunker geometry). This method, which is suitable for routine clinical use, will help to systematically generate the dosimetric data essential for the improvement of current risk-estimation models.

F Snchez-Doblado; C Domingo; F Gmez; B Snchez-Nieto; J L Muiz; M J Garca-Fust; M R Expsito; R Barquero; G Hartmann; J A Terrn; J Pena; R Mndez; F Gutirrez; F X Guerre; J Rosell; L Nez; L Brualla-Gonzlez; F Manchado; A Lorente; E Gallego; R Capote; D Planes; J I Lagares; X Gonzlez-Soto; F Sansaloni; R Colmenares; K Amgarou; E Morales; R Bedogni; J P Cano; F Fernndez

2012-01-01T23:59:59.000Z

71

The estimation of radiation doses in human organs due to natural and artificial radioactivity in surface waters of the Ebro river basin (Northeast Spain)  

Science Journals Connector (OSTI)

This paper reports the estimation of the radiation doses in the human body in the Ebro river basin (Northeast Spain), following drinking water ingestion by measuring 40K, 226Ra, 90Sr and 3H. The equivalent dose in ten different organs was estimated. Dose calculations were performed by means of the GENII computer program. The lowest equivalent dose calculated through ingesting drinking water was in the small intestine whereas the highest was in the bone surface.

Feda Oner; Nazmi T. Okumusoglu

2006-01-01T23:59:59.000Z

72

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

73

Estimation of low-level neutron dose-equivalent rate by using extrapolation method for a curie level AmBe neutron source  

Science Journals Connector (OSTI)

Abstract Neutron radiation protection is an important research area because of the strong radiation biological effect of neutron field. The radiation dose of neutron is closely related to the neutron energy, and the connected relationship is a complex function of energy. For the low-level neutron radiation field (e.g. the AmBe source), the commonly used commercial neutron dosimeter cannot always reflect the low-level dose rate, which is restricted by its own sensitivity limit and measuring range. In this paper, the intensity distribution of neutron field caused by a curie level AmBe neutron source was investigated by measuring the count rates obtained through a 3He proportional counter at different locations around the source. The results indicate that the count rates outside of the source room are negligible compared with the count rates measured in the source room. In the source room, 3He proportional counter and neutron dosimeter were used to measure the count rates and dose rates respectively at different distances to the source. The results indicate that both the count rates and dose rates decrease exponentially with the increasing distance, and the dose rates measured by a commercial dosimeter are in good agreement with the results calculated by the Geant4 simulation within the inherent errors recommended by ICRP and IEC. Further studies presented in this paper indicate that the low-level neutron dose equivalent rates in the source room increase exponentially with the increasing low-energy neutron count rates when the source is lifted from the shield with different radiation intensities. Based on this relationship as well as the count rates measured at larger distance to the source, the dose rates can be calculated approximately by the extrapolation method. This principle can be used to estimate the low level neutron dose values in the source room which cannot be measured directly by a commercial dosimeter.

Gang Li; Jiayun Xu; Jie Zhang

2015-01-01T23:59:59.000Z

74

Radiation dose rates from UF{sub 6} cylinders  

SciTech Connect

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

Friend, P.J. [Urenco, Capenhurst (United Kingdom)

1991-12-31T23:59:59.000Z

75

The effect of different adaptation strengths on image quality and radiation dose using Siemens Care Dose 4D  

Science Journals Connector (OSTI)

......undertaking strategies for CT radiation dose optimisation...supported by the Swedish Radiation Safety Authority (SSI P 1579...4D new technique for radiation dose reduction. SOMATOM...Application Guide. Software Version syngo CT 2005A......

Marcus Sderberg; Mikael Gunnarsson

2010-01-01T23:59:59.000Z

76

Estimation of the contribution of photon radiation for measurement of the exposure dose rate of neutron sources based on 252Cf  

Science Journals Connector (OSTI)

A method for the estimation of the contribution of photon radiation to the detector readings for measurement of the exposure dose rate and the equivalent activity of neutron ... screens and filters is considered....

N. F. Demchenko; R. N. Minvaliev; V. I. Shipilov

2012-06-01T23:59:59.000Z

77

74Exploring Nuclear Decay and Radiation Dose The devastating earthquake  

E-Print Network (OSTI)

74Exploring Nuclear Decay and Radiation Dose The devastating earthquake that struck northern Japan vent radioactive gas and dust clouds into the environment. Although the initial radiation levels were extremely high, the natural decay of the radioactive compounds will cause the radiation levels at any given

78

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

79

Molecular Mechanism Underlying Cellular Adaptive Response to Low Dose Radiation  

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

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

80

E-Print Network 3.0 - assessing radiation dose Sample Search...  

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

of radiation; radiation measurement; and dose information. ATOMS... Assessments, DOETIC-11026. RADIATION Radiation, or radiant energy, is energy in the form of waves... )...

Note: This page contains sample records for the topic "radiation dose equivalent" 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.


81

ORISE: Radiation Dose Estimates and Other Compendia  

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

downloaded free from the Adobe website. Early Internal and External Dose Magnitude Estimation (PDF) This article addresses methods that can be used to rapidly estimate internal...

82

Low Dose Radiation Research Program: 2003 Molecular Characterization of the  

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

Characterization of the Roles of SOD Genes in Mammalian Characterization of the Roles of SOD Genes in Mammalian Cellular Response to Low Dose Radiation Authors: Chuan-Yuan Li,1 Eric Chuang2 Institutions: 1Dept of Radiation Oncology, Duke University Medical Center, Durham, NC, 2Advanced Technology Center, Center for Cancer Research, National Cancer Institute, Bethesda, Maryland The potential risks of exposure to low dose radiation are of major concerns to the DOE/OBER Low Dose Radiation Research Program. It has been long recognized that much of the radiation-induced genetic damage to cells are caused by secondary oxidative species. Therefore, internal cellular defense systems against oxidative stress play significant roles in countering genetic damage induced by ionizing radiation. The role of the detoxifying

83

Low Dose Radiation Research Program: Molecular Characterization of the  

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

Molecular Characterization of the Roles of SOD Genes in Mammalian Molecular Characterization of the Roles of SOD Genes in Mammalian Cellular Response to Low Dose Radiation Authors: Chuan-Yuan Li, Zhanjun Guo, Zhonghui Yang, and Eric Chuang Institutions: Dept of Radiation Oncology, Duke University Medical Center, Durham, NC Advanced Technology Center, Center for Cancer Research, National Cancer Institute, Bethesda, Maryland Background The potential risks of exposure to low dose radiation are of major concerns to the DOE/OBER Low Dose Radiation Research Program. It has been long recognized that much of the radiation-induced genetic damage to cells are caused by secondary oxidative species. Therefore internal cellular defense systems against oxidative stress play significant roles in countering genetic damage induced by ionizing radiation. The role of the detoxifying

84

Measurement of radiation dose in dental radiology  

Science Journals Connector (OSTI)

......product to effective dose and energy imparted to the patient. Phys...C. A. and Persliden, J. Energy imparted to the patient in diagnostic...factors for determining the energy imparted from measurements of...dental radiology. | Patient dose audit is an important tool for quality......

Ebba Helmrot; Gudrun Alm Carlsson

2005-05-01T23:59:59.000Z

85

Low Dose Radiation Research Program: Chaun-Yuan Li  

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

Chaun-Yuan Li Chaun-Yuan Li Radiation Biology Research, Duke University Medical Center Funded Projects Molecular Characterization of the Role of SOD Genes in Mammalian Cellular Response to Low Dose Ionizing, abstract, description. Technical Abstracts 2006 Workshop: The Roles of Superoxide Dismutage (SOD) in Low Dose Radiation Induced Adaptive Response Yang, Z., Chuang, E., Batinic-Haberle, I., and Li, C.-Y. 2005 Workshop: Molecular Characterization of the Roles of SOD Genes in Mammalian Cellular Response to Low Dose Radiation Li, C.-Y., Guo, Z., Yang, Z., and Chuang, E. 2003 Workshop: Molecular Characterization of the Roles of SOD Genes in Mammalian Cellular Response to Low Dose Radiation Li, C.-Y. and Chuang, E. Publications Li, F., Sonveaux, P., Rabbani, Z.N., Liu, S., Yan, B., Huang, Q.,

86

Low Dose Radiation Research Program: Research Highlights - Health Physics  

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

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

87

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

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

Annual report shows potential INL radiation doses well below safe regulatory limits July 21, 2010 Media contact: Tim Jackson (208) 526-8484 Idaho Falls, ID The U.S. Department...

88

Low Dose Radiation Program: Links - Agencies with Radiation Regulatory  

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

Agencies with Radiation Regulatory Concerns and Involvement Agencies with Radiation Regulatory Concerns and Involvement Biological Effects of Low Level Exposures (BELLE) Canadian Nuclear Safety Commission Center for Risk Excellence Health Protection Agency The Health Risks of Extraterrestrial Environments International Commission on Radiation Units and Measurements, Inc. International Commission on Radiological Protection (ICRP) International Radiation Protection Association (IRPA) NASA Space Radiation Program National Academy of Sciences (NAS) Nuclear and Radiation Studies Board National Aeronautics and Space Administration (NASA) NASA OBRR Task Book Publication National Council on Radiation Protection (NCRP) National Institute of Environmental Health Sciences (NIEHS) National Toxicology Program (NTP) Occupational Safety and Health Administration (OSHA)

89

Low Dose Radiation Research Program: Genetic Factors Affecting  

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

Genetic Factors Affecting Susceptibility to Low-Doses of Ionizing Genetic Factors Affecting Susceptibility to Low-Doses of Ionizing Radiation. Authors: William F. Morgan, Pat Concannon & John H.J. Petrini The goal of this program is to test the hypothesis that mice heterozygous for the NBS1 gene are genetically susceptible to low doses of ionizing radiation. Patients with Nijmegen Breakage Syndrome (NBS) are radiation sensitive, because of defects in cellular responses to radiation induced genetic damage. It is unclear whether humans heterozygous for the mutations associated with NBS are radiation sensitive and results from cell culture experiments give conflicting results. In collaboration with John Petrini at the Memorial Sloan Kettering Cancer Center in New York City we developed a mouse model of this disorder and are directly testing the hypothesis

90

Low Dose Radiation Research Program: Earlier Events  

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

Earlier Events Earlier Events 2000 | 2001 | 2002 | 2003 | 2004 April 2000 Ionizing Radiation Science and Protection in the 21st Century, NCRP, April 5-6, Arlington, VA. RADIATION RESEARCH 2000, Association for Radiation Research, April 10-12, Bristol, UK. Florida Chapter of the Health Physics Society Spring 2000 Meeting, Gainesville, FL, April 13-14. 47th Annual Meeting of the Radiation Research Society, April 29-May 3, Albuquerque, NM. May 2000 IRPA-10 International Congress 2000, May 14-19, Hiroshima, Japan. IRPA-10 Secretariat, c/o Japan Convention Services, Inc., Nippon Press Center Building, 2-2-1, Uchisaiwai-cho, Chiyoda-ku, Tokyo 100, Japan. Phone: 81-3-3508-1214. Fax: 81-3-3508-0820. irpa10@convention.jp. 4th International Non-Ionizing Radiation Workshop, May 22-25, Kyoto,

91

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

DOE Patents (OSTI)

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

Horn, Kevin M.

2013-07-09T23:59:59.000Z

92

Radiation dose modeling using IGRIP and Deneb/ERGO  

SciTech Connect

The Radiological Environment Modeling System (REMS) quantifies dose to humans in radiation environments using the IGRIP (Interactive Graphical Robot Instruction Program) and Deneb/ERGO (Ergonomics) simulation software products. These commercially available products are augmented with custom C code to provide the radiation exposure information to and collect the radiation dose information from the workcell simulations. The emphasis of this paper is on the IGRIP and Deneb/ERGO parts of REMS, since that represents the extension to existing capabilities developed by the authors. Through the use of any radiation transport code or measured data, a radiation exposure input database may be formulated. User-specified IGRIP simulations utilize these database files to compute and accumulate dose to human devices (Deneb`s ERGO human) during simulated operations around radiation sources. Timing, distances, shielding, and human activity may be modeled accurately in the simulations. The accumulated dose is recorded in output files, and the user is able to process and view this output. REMS was developed because the proposed reduction in the yearly radiation exposure limit will preclude or require changes in many of the manual operations currently being utilized in the Weapons Complex. This is particularly relevant in the area of dismantlement activities at the Pantex Plant in Amarillo, TX. Therefore, a capability was needed to be able to quantify the dose associated with certain manual processes so that the benefits of automation could be identified and understood.

Vickers, D.S.; Davis, K.R.; Breazeal, N.L.; Watson, R.A. [Sandia National Labs., Albuquerque, NM (United States); Ford, M.S. [Battelle Pantex, Amarillo, TX (United States). Dept. of Radiation Safety

1995-12-31T23:59:59.000Z

93

Radiation Dose-Volume Effects in the Heart  

SciTech Connect

The literature is reviewed to identify the main clinical and dose-volume predictors for acute and late radiation-induced heart disease. A clear quantitative dose and/or volume dependence for most cardiac toxicity has not yet been shown, primarily because of the scarcity of the data. Several clinical factors, such as age, comorbidities and doxorubicin use, appear to increase the risk of injury. The existing dose-volume data is presented, as well as suggestions for future investigations to better define radiation-induced cardiac injury.

Gagliardi, Giovanna, E-mail: giovanna.gagliardi@karolinska.s [Department of Medical Physics, Karolinska University Hospital and Karolinska Institute, Stockholm (Sweden); Constine, Louis S. [Department of Radiation Oncology, University of Rochester Cancer Center, Rochester, NY (United States); Moiseenko, Vitali [Vancouver Cancer Centre, British Columbia Cancer Agency, Vancouver, BC (Canada); Correa, Candace; Pierce, Lori J. [Department of Radiation Oncology, University of Michigan, Ann Arbor, MI (United States); Allen, Aaron M. [Department of Radiation Oncology, Dana- Farber Cancer Institute, Boston, MA (United States); Rabin Medical Center Petach Tikvah (Israel); Marks, Lawrence B. [Department of Radiation Oncology, University of North Carolina, Chapel Hill, NC (United States)

2010-03-01T23:59:59.000Z

94

Low Dose Radiation Research Program: Melvyn Folkard  

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

Melvyn Folkard Melvyn Folkard Gray Cancer Institute About this Project Currently Funded Projects A Variable Energy Soft X-ray Microprobe to Investigate Mechanisms of the Radiation-Induced Bystander Effect Technical Abstracts 2005 Workshop: A Variable-Energy Soft X-Ray Microprobe to Investiage Mechanisms of the Radiation-Induced Bystander Effect Folkard, M., Vojnovic, B., Schettiono, G., Atkinson, K., Prise, K.M., Michael, B.D. 2003 Workshop: A Variable-Energy Soft X-Ray Microprobe to Investigate Mechanisms of the Radiation -Induced Bystander Effect. Folkard, M., Vojnovic, B., Schettino, G., Atkinson, K., Prise, K.M., Michael, B.D. 2002 Workshop: A Variable-Energy Soft X-ray Microprobe to Investigate Mechanisms of the Radiation-Induced Bystander Effect. Folkard, M., Vojnovic, B., Schettino,

95

Radiation Dose Metrics in CT: Assessing Dose Using the National Quality Forum CT Patient Safety Measure  

Science Journals Connector (OSTI)

Purpose The National Quality Forum (NQF) is a nonprofit consensus organization that recently endorsed a measure focused on CT radiation doses. To comply, facilities must summarize the doses from consecutive scans within age and anatomic area strata and report the data in the medical record. Our purpose was to assess the time needed to assemble the data and to demonstrate how review of such data permits a facility to understand doses. Methods and Materials To assemble the data we used for analysis, we used the dose monitoring softwareeXposure to automatically export dose metrics from consecutive scans in 2010 and 2012. For a subset of 50exams, we also collected dose metrics manually, copying data directly from the PACS into an excel spreadsheet. Results Manual data collection for 50 scans required 2 hours and 15 minutes. eXposure compiled the data in under an hour. All dose metrics demonstrated a 30% to 50% reduction between 2010 and 2012. There was also a significant decline and a reduction in the variability of the doses over time. Conclusion The NQF measure facilitates an institution's capacity to assess the doses they are using for CT as part of routine practice. The necessary data can be collected within a reasonable amount of time either with automatic software or manually. The collection and review of these data will allow facilities to compare their radiation dose distributions with national distributions and allow assessment of temporal trends in the doses they are using.

Jillian Keegan; Diana L. Miglioretti; Robert Gould; Lane F. Donnelly; Nicole D. Wilson; Rebecca Smith-Bindman

2014-01-01T23:59:59.000Z

96

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

97

Low Dose Radiation Research Program: DOE / NASA Joint Funded Projects  

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

DOE/NASA Joint Funded Projects DOE/NASA Joint Funded Projects NASA Source Photo Space explorers are subject to exposure to low dose ionizing radiation. Research that helps determine health risks from this exposure is funded by NASA and DOE. Source: NASA DOE's Low Dose Program and the National Aeronautics and Space Administration (NASA) jointly fund new research to develop a better scientific basis for understanding risks to humans from exposures to low doses or low fluences of ionizing radiation. Research must focus on elucidating molecular mechanisms and pathways involved in normal radiobiological responses to low dose exposure, and must have the potential to ultimately increase understanding of health outcomes from radiation exposures that are at or near current workplace exposure

98

Low Dose Radiation Exposure: Exploring Bystander Effects In Vivo.  

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

Exposure: Exploring Bystander Effects Exposure: Exploring Bystander Effects In Vivo. 1 Blyth, B.J., 1 Sykes, P.J. 1 Department of Haematology and Genetic Pathology, Flinders University and Medical Centre, Bedford Park, South Australia, 5042, The general population is daily exposed to chronic, low doses of ionizing radiation from both natural and artificial sources. The shape of the radiation dose-response curve at these low doses is currently linearly extrapolated from data obtained after high dose exposure due to the low sensitivity of traditional biological assays after near-background exposures. At odds with this Linear No-Threshold model, are the phenomena collectively referred to as the radiation-induced bystander effect. The bystander effect describes a collection of in vitro

99

Low Dose Radiation Program: Workshops, Proceedings, Abstracts and Programs  

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

Workshops, Proceedings, Abstracts and Programs Workshops, Proceedings, Abstracts and Programs UPDATE: Investigators' Workshop Postponed The annual Low Dose Radiation Research Program Investigators' Workshop typically held in April or May has been postponed until next year. Please keep checking the website for updates. 2010 The 2010 DOE Low Dose Radiation Research Investigators' Workshop was held April 12-14, 2010, 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. See link for investigators' abstracts. 2009 The DOE Low Dose Radiation Research Investigators' Workshop VIII was held

100

Low Dose Radiation Research Program: Current Funded Project Descriptions  

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

Funded Project Descriptions Funded Project Descriptions Effects Of Low Doses of Radiation on DNA Repair Jointly funded by NASA and DOE Eric J Ackerman Pacific Northwest National Laboratory Richland, WA 99352 Dr. Ackerman will study the effect of low doses of ionizing radiation on the repair of different types of damage to DNA, including damage from ionizing radiation and that produced by the normal internal operation of the cell. Using a very sensitive technique called host cell reactivation assay (HCR), he will quantitatively measure the repair of each type of DNA damage and thereby measure if the cellular repair system itself has been damaged. He will also determine if unique forms of DNA repair system damage are induced by low doses of cosmic radiation exposure present during space

Note: This page contains sample records for the topic "radiation dose equivalent" 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.


101

Low Dose Radiation Research Program: Marianne B. Sowa  

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

Marianne B. Sowa Marianne B. Sowa PNNL - Pacific Northwest National Laboratory Funded Projects A Mechanistic Study of the Radiation Quality Dependence of Bystander Effects in Human Cells 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. Morphological Changes in a 3D Mammary Model Following Exposure to Low Dose, Low-LET Radiation Opresko, L.K., Chrisler, W., Emory, K., Arthurs, B., and Sowa, M.B. 2005 Workshops: Using a Low LET Electron Microbeam to Investigate Non-Targeted Effects of Low Dose Radiation Morgan, W.F. and Sowa, M.B. Publications Perrine, K.A., Lamarche, B.L., Hopkins, D.F., Budge, S.E., Opresko, L.K., Wiley, H.S., and Sowa, M.B. (2007). High speed method for in situ

102

Low Dose Radiation Research Program: Project Descriptions-Archive  

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

Project Descriptions-Archive Project Descriptions-Archive Effects Of Low Doses of Radiation on DNA Repair Eric J Ackerman (former PNNL) (Jointly funded by NASA and DOE) Pacific Northwest National Laboratory Richland, WA Dr. Ackerman will study the effect of low doses of ionizing radiation on the repair of different types of damage to DNA, including damage from ionizing radiation and that produced by the normal internal operation of the cell. Using a very sensitive technique called host cell reactivation assay (HCR), he will quantitatively measure the repair of each type of DNA damage and thereby measure if the cellular repair system itself has been damaged. He will also determine if unique forms of DNA repair system damage are induced by low doses of cosmic radiation exposure present during space

103

Quantitative estimation of UV light dose concomitant to irradiation with ionizing radiation  

Science Journals Connector (OSTI)

A simple mathematical model for biological estimation of UV light dose concomitant to ionizing radiation was suggested. This approach was applied to determine the dependency of equivalent UV light dose accompanied by 100Gy of ionizing radiation on energy of sparsely ionizing radiation and on volume of the exposed cell suspension. It was revealed that the relative excitation contribution to the total lethal effect and the value of UV dose was greatly increased with an increase in energy of ionizing radiation and volume of irradiated suspensions. It is concluded that these observations are in agreement with the supposition that ?erenkov emission is responsible for the production of UV light damage and the phenomenon of photoreactivation observed after ionizing exposure of bacterial and yeast cells hypersensitive to UV light. A possible synergistic interaction of the damages produced by ionizations and excitations as well as a probable participation of UV component of ionizing radiation in the mechanism of hormesis and adaptive response observed after ionizing radiation exposure is discussed.

Vladislav G. Petin; Ivan I. Morozov; Jin Kyu Kim; Maria A. Semkina

2011-01-01T23:59:59.000Z

104

Low-Dose Radiation Cataract and Genetic Determinants of Radiosensitivity  

SciTech Connect

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

Kleiman, Norman Jay [Columbia University] [Columbia University

2013-11-30T23:59:59.000Z

105

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

106

Low Dose Radiation Research Program: What's New Archive  

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

What's New What's New Tony Brooks Chosen As Lauriston S. Taylor Lecturer Congratulations to radiation biologist Dr. Antone "Tony" Brooks, a consultant to the Pacific Northwest National Laboratory's Low Dose Radiation Research Program, on his selection to give the 36th Lauriston S. Taylor Lecture at the Annual Meeting of the National Council on Radiation Protection and Measurements (NCRP). Brooks is former chief scientist for the U.S. Department of Energy's Low Dose Radiation Research Program. His lecture, titled "From the Field to the Laboratory and Back: The What Ifs, Wows, and Who Cares of Radiation Biology," will be a featured presentation at the meeting, which will be held March 12 and 13, 2012, at the Hyatt Regency Bethesda, Bethesda, Maryland.

107

Low dose radiation combines with the Src oncoprotein to transform  

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

radiation combines with the Src oncoprotein to transform radiation combines with the Src oncoprotein to transform pre-malignant human breast cells Paul Yaswen Lawrence Berkeley National Laboratory Abstract Goal: Determine whether low dose radiation exerts persistent epigenetic effects that promote malignancy. Background and Significance: Some persistent carcinogenic effects of radiation may not be traceable to specific DNA sequence alterations and may not be linearly related to dose. Through the biochemical initiation of positive feedback loops, ionization-induced events may have heritable non-linear effects on cellular behavior. Inflammatory responses involving the transcription factor NFκB may be subject to such effects. Increased NFκB activity has been strongly linked to carcinogenesis in a number of published in vitro and in vivo studies (reviewed in [1]). Since radiation

108

Radiation Pneumonitis After Hypofractionated Radiotherapy: Evaluation of the LQ(L) Model and Different Dose Parameters  

SciTech Connect

Purpose: To evaluate the linear quadratic (LQ) model for hypofractionated radiotherapy within the context of predicting radiation pneumonitis (RP) and to investigate the effect if a linear (L) model in the high region (LQL model) is used. Methods and Materials: The radiation doses used for 128 patients treated with hypofractionated radiotherapy were converted to the equivalent doses given in fractions of 2 Gy for a range of {alpha}/{beta} ratios (1 Gy to infinity) according to the LQ(L) model. For the LQL model, different cut-off values between the LQ model and the linear component were used. The Lyman model parameters were fitted to the events of RP grade 2 or higher to derive the normal tissue complication probability (NTCP). The lung dose was calculated as the mean lung dose and the percentage of lung volume (V) receiving doses higher than a threshold dose of xGy (V{sub x}). Results: The best NTCP fit was found if the mean lung dose, or V{sub x}, was calculated with an {alpha}/{beta} ratio of 3 Gy. The NTCP fit of other {alpha}/{beta} ratios and the LQL model were worse but within the 95% confidence interval of the NTCP fit of the LQ model with an {alpha}/{beta} ratio of 3 Gy. The V{sub 50} NTCP fit was better than the NTCP fit of lower threshold doses. Conclusions: For high fraction doses, the LQ model with an {alpha}/{beta} ratio of 3 Gy was the best method for converting the physical lung dose to predict RP.

Borst, Gerben R. [Department of Radiation Oncology, Netherlands Cancer Institute-Antoni van Leeuwenhoek Hospital, Amsterdam (Netherlands); Ishikawa, Masayori [Department of Radiology, Hokkaido University School of Medicine, Sapporo (Japan); Nijkamp, Jasper [Department of Radiation Oncology, Netherlands Cancer Institute-Antoni van Leeuwenhoek Hospital, Amsterdam (Netherlands)

2010-08-01T23:59:59.000Z

109

Low Dose Radiation Research Program: Do Heritable Differences in an  

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

Do Heritable Differences in an Individual's Immune System Predict Do Heritable Differences in an Individual's Immune System Predict Differential Sensitivity to Low Dose Radiation Exposure? Quantitative trait loci (QTL) mapping Enlarge Image Quantitative trait loci (QTL) mapping identifies two strong candidate genes, Ptprk (Chr 10) and Acp1 (Chr 12) that are linked to genetic variation in the relative abundance of peripheral Th and Tc cells, two cell populations that are sensitive to radiation exposure at low doses. Expression of each gene is significantly altered by exposure to low dose radiation in vivo. Genome-wide scans for the ratio of %CD4+ (Th) to %CD8+ (Tc) lymphocytes were performed using genenetwork.org. The solid horizontal line represents genome-wide significance at P < 0.05, based on 1,000 permutations. LOD indicates logarithm of odds scores.

110

Persistent DNA damage foci, cellular senescence and low dose radiation  

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

Persistent DNA damage foci, cellular senescence and low dose radiation Persistent DNA damage foci, cellular senescence and low dose radiation Denise Munoz 1 , Albert Davalos 1 , Francis Rodier 1 , Misako Kawahara 1 , Judith Campisi 1,2 and Steven Yannone 1,3 1 Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Mailstop 84-171, Berkeley CA 94720; 2 Buck Institute for Age Research, 8001 Redwood Boulevard, Novato CA 94945; 3 Corresponding author Ionizing radiation (IR) induced DNA double-strand breaks (DSBs) are cytologically detectable as large nuclear foci that contain phosphorylated histone H2AX (γH2AX), the adaptor protein 53BP1, and several other proteins that participate in the sensing and processing of DNA damage (DNA damage foci). In normal human cells, moderately high IR (0.5-1 Gy) doses cause the rapid appearance of these foci (acute DNA damage foci), which gradually disappear

111

Low Dose Radiation Research Program: Biologically Based Analysis of Lung  

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

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,

112

Concurrent Temozolomide and Dose-Escalated Intensity-Modulated Radiation Therapy in Newly Diagnosed Glioblastoma  

Science Journals Connector (OSTI)

...dose (MTD) of radiation (RT) with concurrent...We show the safety and tolerability...delivering higher radiation (RT) doses with...tools (FIAT), a software package developed...Development of image software tools for radiation therapy assessment...

Christina I. Tsien; Doris Brown; Daniel Normolle; Matthew Schipper; Morand Piert; Larry Junck; Jason Heth; Diana Gomez-Hassan; Randall K. Ten Haken; Thomas Chenevert; Yue Cao; and Theodore Lawrence

2012-01-01T23:59:59.000Z

113

Radiation dose distribution for workers in South Korean nuclear power plants  

Science Journals Connector (OSTI)

......KHNP has implemented a radiation safety management system...dose registry of NPPs radiation workers, in order to...existing plants. From the software point of view, training...annual average individual radiation exposure dose is expected......

Byoung-il Lee; So-i Kim; Dong-hee Suh; Young-woo Jin; Jeong-in Kim; Hoon Choi; Young-khi Lim

2010-07-01T23:59:59.000Z

114

Radiation doses from some common paediatric X-ray examinations in Sudan  

Science Journals Connector (OSTI)

......and Technical Papers Radiation doses from some common...suliman@gmail.com Radiation Safety Institute, Sudan Atomic...3001, Khartoum, Sudan Radiation doses to patients from...settings using DosCal software. Totally, 459 patients......

I. I. Suliman; E. H. A. Elshiekh

2008-12-01T23:59:59.000Z

115

Radiation dose management in CT, SPECT/CT and PET/CT techniques  

Science Journals Connector (OSTI)

......report from the Swedish Radiation Safety Authority showed that...of the collective radiation dose in Sweden in 2005...more and more wasted radiation dose is delivered to...overscanning(37). Both a software solution(38) and......

Sren Mattsson; Marcus Sderberg

2011-09-01T23:59:59.000Z

116

Extremely Low Dose Ionizing Radiation Up-regulates CXC Chemokines in Normal Human Fibroblasts  

Science Journals Connector (OSTI)

...with radiation exposure (1). Ionizing radiation at moderate and higher doses (0.1-10 Gy) can produce DNA strand...death. Studies of mutants sensitive to ionizing radiation at this range of doses have revealed that the responsible genes...

Akira Fujimori; Ryuichi Okayasu; Hiroshi Ishihara; Satoshi Yoshida; Kiyomi Eguchi-Kasai; Kumie Nojima; Satoru Ebisawa; and Sentaro Takahashi

2005-11-15T23:59:59.000Z

117

Low Dose Radiation Research Program: Adaptive Response of Mouse Skin  

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

Adaptive Response of Mouse Skin Epithelial Cells to Low Dose Adaptive Response of Mouse Skin Epithelial Cells to Low Dose Ionizing Radiation: Induction of NF-κB, MnSOD, 14-3-3ζ and Cyclin B1 Authors: Jian Jian Li, Kazi M. Ahmed, Ming Fan, Shaozhong Dong, Douglas R. Spitz, and Cheng-Rong Yu Institutions: Division of Molecular Radiobiology, Purdue University School of Health Sciences, West Lafayette, Indiana; Free Radical and Radiation Biology Program, Department of Radiation Oncology, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, Iowa; Molecular Immunology Section, Laboratory of Immunology, National Eye Institute, National Institutes of Health, Bethesda, Maryland Gene expression profiles demonstrate that a group of key stress-responsive genes are associated with radiation exposure and may contribute to cellular

118

Low Dose Radiation Research Program: Molecular Mechanisms of  

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

Molecular Mechanisms of Radiation-Induced Genomic Instability in Molecular Mechanisms of Radiation-Induced Genomic Instability in Human Cells. Authors: Howard L. Liber1 and Jeffrey L. Schwartz2. Institutions: 1Colorado State University and 2University of Washington. Knowledge of the signal and target through which radiation induces genomic instability, which we propose to investigate herein, will allow us to model effects at low doses. Such knowledge will aid in understanding variations in the induction of this genomic instability, both among cells and among individuals. This information could also lead to more sensitive measures of instability that could yield accurate measures of instability induction at low doses. We have developed an in-vitro cell model, in which radiation-induced chromosome instability develops in a two-stage process.

119

Low Dose Radiation Research Program: Molecular Characterization of Survival  

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

Survival Advantage, Bystander Effect, and Survival Advantage, Bystander Effect, and Genomic Instability after Low-LET Low Dose Radiation Exposure Mohan Natarajan University of Texas Health Science Center Why this Project? To understand the molecular link between the activation of NF-kB and cellular outcomes such as better cell survival after low-LET radiation and to determine whether low dose radiation-induced NF-kB signaling can mediate telomerase activation and thus confer enhanced cell survival of normal aortic endothelial cells. Project Goals To determine whether low-linear energy transfer (LET) radiation can cause a positive feedback signal initiated by the activation of the NF-kB. To examine one of the mechanisms involving TNF-a as a signaling mediator, which could mediate the bystander effect through the generation

120

Low Dose Radiation Research Program: Janet E. Baulch  

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

Janet E. Baulch Janet E. Baulch University of California, Davis Currently Funded Projects Impact of Genetic Factors on the Heritable Effects of Paternal Exposure to Low-Dose Radiation Technical Abstracts 2003 Workshop: DNA damage in acutely irradiated F2 mice with a history of paternal F0 germline irradiation Baulch, J.E. and Raabe, O G. 2002 Workshop Impact of Genetic Factors on the Heritable Effects of Paternal Exposure to Low-Dose Radiation, Baulch, J.E., Ph.D. and Raabe, O.G., Ph.D. Publications Kovalchuk, O. and Baulch, J.E. (2008). Epigenetic changes and nontargeted radiation effects - Is there a link? Environmental and Molecular Mutagenesis 49(1):16-25 Laiakis, E.C., Baulch, J.E., and Morgan, W.F. (2008). Interleukin 8 exhibits a pro-mitogenic and pro-survival role in radiation induced

Note: This page contains sample records for the topic "radiation dose equivalent" 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: Frequencies of Radiation-Induced  

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

Frequencies of Radiation-Induced Chromosome Interchanges and Frequencies of Radiation-Induced Chromosome Interchanges and Randomness of Chromosome Territory Locations Relative to One Another. Authors: RK Sachs,§ MN Cornforth,‡ KM Greulich-Bode,* L Hlatky, and DJ Brenner|| Institutions: §Department of Mathematics, University of California, ‡University of Texas Medical Branch, *Department of Skin Carcinogenesis, German Cancer Research Center DFCI, Harvard Medical School, ||Center for Radiological Research, Columbia University. Leukemogenesis, and perhaps carcinogenesis in general, often involves specific chromosome translocations. Radiation-induced chromosome translocation frequencies are strongly influenced by how close participating chromosomes are to one another in an interphase cell nucleus. We sought to determine whether chromosomes in human peripheral blood

122

United States Department of Energy Low Dose Radiation Research Program  

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

History of the History of the United States Department of Energy (DOE) Low Dose Radiation Research Program: 1998-2008 Dr. Antone L. Brooks tbrooks@tricity.wsu.edu September 2012 Review Draft i Contents Preface............................................................................................................................................. v Summary ........................................................................................................................................ vi Acronyms and Initialisms ............................................................................................................. vii Chapter 1 Introduction ................................................................................................................... 1

123

Human In vivo Dose-Response to Controlled, Low-Dose Low Linear Energy Transfer Ionizing Radiation Exposure  

Science Journals Connector (OSTI)

...biotinylated nucleotide analogue/ribonucleotide mix. The biotinylated cRNA targets were then...dose-response to controlled, low-dose low linear energy transfer ionizing radiation exposure. | The effect of low doses of low-linear energy transfer (photon) ionizing radiation...

Zelanna Goldberg; David M. Rocke; Chad Schwietert; Susanne R. Berglund; Alison Santana; Angela Jones; Jrg Lehmann; Robin Stern; Ruixiao Lu; and Christine Hartmann Siantar

2006-06-15T23:59:59.000Z

124

Low Dose Radiation Research Program: Optimizing the Scientific, Regulatory,  

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

Optimizing the Scientific, Regulatory, and Societal Impact of the DOE Low Optimizing the Scientific, Regulatory, and Societal Impact of the DOE Low Dose Radiation Research Program Antone L. Brooks Why This Project? For maximum benefit, state-of-the-art research and new data from the Low Dose Radiation Research Program must be available to other scientists, regulatory agencies, and the public. This project stays abreast of scientific advances in the field, gathers, integrates, and summarizes the research within the program, and disseminates this information to appropriate scientific, regulatory, and public venues. Project Goals Provides a focal point for distribution of information generated in the program, to scientific committees, other governmental and regulatory agencies, and to the public Provides scientific support for the Low Dose Program website

125

Human In vivo Dose-Response to Controlled, Low-Dose Low Linear Energy Transfer Ionizing Radiation Exposure  

Science Journals Connector (OSTI)

...effects of low-dose low-linear energy transfer ionizing radiation (LDIR) in humans...direct evidence that doses in the range of 1 to 10 cGy...the intentional radiation of healthy tissue...the response to ionizing radiation. Attempts...

Zelanna Goldberg; David M. Rocke; Chad Schwietert; Susanne R. Berglund; Alison Santana; Angela Jones; Jrg Lehmann; Robin Stern; Ruixiao Lu; and Christine Hartmann Siantar

2006-06-15T23:59:59.000Z

126

E-Print Network 3.0 - absorbed radiation dose Sample Search Results  

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

know Summary: . Absorbed dose is the physical quantity describing energy deposited per unit mass. For radiation protection... Cancer risks attributable to low doses of ionizing...

127

Radiation exposure for 'caregivers' during high-dose outpatient radioiodine therapy  

Science Journals Connector (OSTI)

......designed to evaluate radiation safety issues and predict...to comply with radiation safety instructions...list of radiation safety instructions...record cumulative radiation dose for each...using EasyEPD2 software (version 1......

Christopher J. Marriott; Colin E. Webber; Karen Y. Gulenchyn

2007-01-01T23:59:59.000Z

128

Method to Improve Total Dose Radiation Hardness in a CMOS dc-dc Boost  

E-Print Network (OSTI)

in a wide range of radiation environment, with increasing total dose radiation, The efticieney also greatlyMethod to Improve Total Dose Radiation Hardness in a CMOS dc-dc Boost Converter Huadian Pan to natural radiation in space. Among the effects of ionizing radiation are shiftsin threshold voltageand

Wilamowski, Bogdan Maciej

129

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

130

Low Dose Radiation Research Program: Optimizing the Scientific, Regulatory  

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

Optimizing the Scientific, Regulatory and Social Impact of the DOE Optimizing the Scientific, Regulatory and Social Impact of the DOE Low Dose Radiation Research Program. Authors: Antone L.Brooks, Richard J. Bull, Lezlie A. Couch. Institutions: Washington State University Tri-Cities The purpose of this project is to provide scientific, technical, and organizational support to optimize the impact of the DOE Low Dose Radiation Research Program. This project will serve as a focal point for collection and dissemination of scientific information from the scientists funded in the Program to the U.S. Department of Energy (DOE), the regulatory agencies, and the public. The project will be responsible for analysis of the scientific information in the broader context of biomedical research and will provide this information to the Office of Biological Research

131

DOE Low Dose Radiation Research Workshop I November 1999  

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

Low Dose Radiation Research Program Low Dose Radiation Research Program U.S. Department of Energy Office of Biological and Environmental Research David G. Thomassen, Ph.D. Program Coordinator Office of Biological and Environmental Research U.S. Department of Energy, SC-72 19901 Germantown Road Germantown, MD 20874-1290 Phone: 301-903-9817 Fax: 301-903-8521 Email: david.thomassen@science.doe.gov Arthur Katz, Ph.D. Life Sciences Division Office of Biological and Environmental Research U.S. Department of Energy, SC-72 19901 Germantown Road Germantown, MD 20874-1290 Phone: 301-903-4932 Fax: 301-903-8521 Email: arthur.katz@science.doe.gov Marvin E. Frazier, Ph.D. Director, Life Sciences Division Office of Biological and Environmental Research U.S. Department of Energy, SC-72 19901 Germantown Road

132

Patient radiation dose audits for fluoroscopically guided interventional procedures  

SciTech Connect

Purpose: Quality management for any use of medical x-ray imaging should include monitoring of radiation dose. Fluoroscopically guided interventional (FGI) procedures are inherently clinically variable and have the potential for inducing deterministic injuries in patients. The use of a conventional diagnostic reference level is not appropriate for FGI procedures. A similar but more detailed quality process for management of radiation dose in FGI procedures is described. Methods: A method that takes into account both the inherent variability of FGI procedures and the risk of deterministic injuries from these procedures is suggested. The substantial radiation dose level (SRDL) is an absolute action level (with regard to patient follow-up) below which skin injury is highly unlikely and above which skin injury is possible. The quality process for FGI procedures collects data from all instances of a given procedure from a number of facilities into an advisory data set (ADS). An individual facility collects a facility data set (FDS) comprised of all instances of the same procedure at that facility. The individual FDS is then compared to the multifacility ADS with regard to the overall shape of the dose distributions and the percent of instances in both the ADS and the FDS that exceed the SRDL. Results: Samples of an ADS and FDS for percutaneous coronary intervention, using the dose metric of reference air kerma (K{sub a,r}) (i.e., the cumulative air kerma at the reference point), are used to illustrate the proposed quality process for FGI procedures. Investigation is warranted whenever the FDS is noticeably different from the ADS for the specific FGI procedure and particularly in two circumstances: (1) When the facility's local median K{sub a,r} exceeds the 75th percentile of the ADS and (2) when the percent of instances where K{sub a,r} exceeds the facility-selected SRDL is greater for the FDS than for the ADS. Conclusions: Analysis of the two data sets (ADS and FDS) and of the percent of instances that exceed the SRDL provides a means for the facility to better manage radiation dose (and therefore both deterministic and stochastic radiation risk) to the patient during FGI procedures.

Balter, Stephen; Rosenstein, Marvin; Miller, Donald L.; Schueler, Beth; Spelic, David [Department of Radiology and Department of Medicine, Columbia University, New York, New York 10032 (United States); Clarksburg, Maryland 20871 (United States); Department of Radiology, F. Edward Hebert School of Medicine, Uniformed Services University, Bethesda, Maryland 20814 (United States); Department of Radiology, Mayo Clinic and Foundation, Rochester, Minnesota 55905 (United States); Division of Mammography Quality and Radiation Programs, Food and Drug Administration, 10903 New Hampshire Avenue, Silver Spring, Maryland 20903 (United States)

2011-03-15T23:59:59.000Z

133

extremely low-dose ionizing radiation upregulates CXC chemokines in normal human fibroblasts  

Science Journals Connector (OSTI)

...2006 Abstract Tumor Biology 32: Radiation Biology 2 Proc Amer Assoc Cancer...Volume 47, 2006 extremely low-dose ionizing radiation upregulates CXC chemokines in...biological effects of this low dose range have not been established. We...

Akira Fujimori; Katsutoshi Suetomi; Keiji Kinoshita; Ayako Kojima; Yaqun Fang; Ayako Egusa; and Ryuichi Okayasu

2006-04-15T23:59:59.000Z

134

Radiation Dose Estimation from the Analysis of Radionuclides in Marine Fish of the Bay of Bengal  

Science Journals Connector (OSTI)

...Radiation Protection Dosimetry Article Radiation Dose Estimation from the Analysis of Radionuclides in Marine Fish of the Bay of Bengal S. Ghose M.N. Alam M.N...respectively. The annual effective doses due to ingestion of radionuclides......

S. Ghose; M.N. Alam; M.N. Islam

2000-02-01T23:59:59.000Z

135

Low Dose Radiation Research Program: Jian Jian Li  

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

Jian Jian Li Jian Jian Li School of Health Sciences, Purdue University Newly Funded Projects Regulation of NF-kB and Mn SOD in Low Dose Radiation-Induced Adaptive Responses in Mouse and Human Skin Cells, abstract, description. Technical Abstracts 2006 Workshops: NF-kB Mediated Signaling Network in Low Dose X-Ray Induced Adaptive Protection on Mouse and Human Skin Epithelial Cells Ahmed, K.M., Fan, M., Spitz, and Li, J.J. 2005 Workshops: Adaptive Response of Mouse Skin Epithelial Cells to Low Dose Ionizing Radiation: Induction of NF-κB, MnSOD, 14-3-3ζ and Cyclin B1. Li, J.J., Ahmed, K.M., Fan, M., Dong, S., Spitz, D.R., and Yu, C.-R. 2003 Workshops: Gene Expression Profiles of Human Skin Keratinocytes Exposed to Acute and Chronic Ionizing Radiation Li, J.J., Ozeki, M., Wang, T., Tamae, D., Nelson, D., Wyrobek, A., and

136

Radiation Dose-Volume Effects in the Brain  

SciTech Connect

We have reviewed the published data regarding radiotherapy (RT)-induced brain injury. Radiation necrosis appears a median of 1-2 years after RT; however, cognitive decline develops over many years. The incidence and severity is dose and volume dependent and can also be increased by chemotherapy, age, diabetes, and spatial factors. For fractionated RT with a fraction size of <2.5 Gy, an incidence of radiation necrosis of 5% and 10% is predicted to occur at a biologically effective dose of 120 Gy (range, 100-140) and 150 Gy (range, 140-170), respectively. For twice-daily fractionation, a steep increase in toxicity appears to occur when the biologically effective dose is >80 Gy. For large fraction sizes (>=2.5 Gy), the incidence and severity of toxicity is unpredictable. For single fraction radiosurgery, a clear correlation has been demonstrated between the target size and the risk of adverse events. Substantial variation among different centers' reported outcomes have prevented us from making toxicity-risk predictions. Cognitive dysfunction in children is largely seen for whole brain doses of >=18 Gy. No substantial evidence has shown that RT induces irreversible cognitive decline in adults within 4 years of RT.

Lawrence, Yaacov Richard, E-mail: richard.lawrence@jefferson.ed [Department of Radiation Oncology, Thomas Jefferson University, Philadelphia, PA (United States); Li, X. Allen [Department of Radiation Oncology, Medical College of Wisconsin, Milwaukee, WI (United States); El Naqa, Issam [Department of Radiation Oncology, Washington University School of Medicine, St. Louis, MO (United States); Hahn, Carol A. [Department of Radiation Oncology, Duke University Medical Center, Durham, NC (United States); Marks, Lawrence B. [Department of Radiation Oncology, University of North Carolina, Chapel Hill, NC (United States); Merchant, Thomas E. [Department of Radiation Oncology, St. Jude Children's Research Hospital, Memphis, TN (United States); Dicker, Adam P. [Department of Radiation Oncology, Thomas Jefferson University, Philadelphia, PA (United States)

2010-03-01T23:59:59.000Z

137

Low Dose Radiation Research Program: Radiation-Induced Nuclear Factor kB  

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

Radiation-Induced Nuclear Factor kB mediates survival advantage by Radiation-Induced Nuclear Factor kB mediates survival advantage by Telomerase Activation. Authors: Natarajan M.,1 Mohan S.,2 Pandeswara, S.L.,1 and Herman T.S.1 Institutions: Departments of 1Radiation Oncology and 2Pathology, The University of Texas Health Science Center, San Antonio, Texas Activation of NF-kB in response to low doses of ionizing radiation was first shown in our laboratory. Although studies have shown that NF-kB plays an important role in anti-apoptotic function, little has been done to understand the molecular link between the activation of NF-kB and cellular outcome such as enhanced cell survival after low dose low-linear transfer (LET) radiation. Because upregulation of telomerase activity is associated with longevity and allows cells to escape from senescence, we hypothesize

138

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

139

R1S-M-2322 TABLE OF EXPOSURE RATE CONSTANTS AND DOSE EQUIVALENT  

E-Print Network (OSTI)

a point source . 4 5. DOSE BUILD-UP FACTORS 7 6. MASS ENERGY ABSORPTION COEFFICIENTS AND LINEAR in units of MeV/photon , (pen/p)air in cm2 /g gives r in R»m2 /Ci«h if the following conversion factors, the contributions from photon energies below 30 keV and X-rays are omitted. (Continue on next page) December 1982

140

MEASUREMENT OF THE HIGH GAMMA RADIATION DOSE USING THE MEMS BASED DOSIMETER AND RADIOLISYS EFFECT  

E-Print Network (OSTI)

radiation dose. If we consider, that the average time of exploitation is estimated to be 40 years and veryMEASUREMENT OF THE HIGH GAMMA RADIATION DOSE USING THE MEMS BASED DOSIMETER AND RADIOLISYS EFFECT M of high and very high doses of ionizing radiation is crucial for the monitoring of the existing Nuclear

Boyer, Edmond

Note: This page contains sample records for the topic "radiation dose equivalent" 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 Research Program: Research Highlights - Ionizing  

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

Affects Cancer Frequency and Characteristics by Acting Affects Cancer Frequency and Characteristics by Acting on the Microenvironment Background: For more than a quarter century the scientific rationale for extrapolating radiation health effects has been underpinned by biophysical target theory. Fundamental to target theory is that the effect (e.g., DNA damage, mutation, cancer) is proportional to dose based on interaction of energy with biological targets, specifically DNA. However, the biology following ionizing radiation is more than just DNA damage, repair, or misrepair. Cellular responses to ionizing radiation can affect phenotype, cell interactions, lineage commitment, differentiation and genomic stability, all of which have been widely documented in cultured cells and many observed in vivo. This class of non-targeted effects induced

142

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.

143

Low Dose Radiation Research Program: Research Highlights - Collateral  

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

Collateral Damage Collateral Damage Using targeted irradiation to understand radiation-induced effects in bystander cells chromosomal A typical example of chromosomal instability induction measured by chromosome-type aberrations in primary human lymphocytes at delay time post-irradiation of a fraction of the cell population. Similar types of aberrations were observed in whole irradiated population but were not observed in untreated cells. Munira Kadhim Background: It has long been understood that radiation exposure can influence cellular changes. Studies indicate that even very low doses of high linear energy transfer (LET) alpha-particle irradiation, such as that from environmental radon, can affect cells. Radiation-induced genomic instability can be observed in the progeny of irradiated cells and as a

144

Low Dose Radiation Research Program: Rainer K. Sachs  

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

Rainer K. Sachs Rainer K. Sachs University of California, Berkeley Funded Projects BIO-BASED RISK MODELING 03-20: Modeling the Interrelations Among Radiation-Induced Bystander Effects, Genomic Instability and Cancer Cytogenetic Tests of Radiobiological Models Relating Epidemiologically Measurable Risks to Low-Dose Risks Technical Abstracts 2006 Workshop The Bystander Effect in Normal Human 3-D Tissue: Experiments, Models, and Implications Brenner, D., Ponnaiya, B., Shuryak, I., Sachs, R., and Geard, D. Radiation Carcinogenesis Risk as Influenced by Intercellular Interaction Hahnfeldt, P., Hlatky, L., and Sachs, R.K. 2005 Workshop: Modelling Intercellular Interactions During Radiation Carcinogenesis Sachs, R.K., Chan, M., Hlatky, L., and Hahnfeldt, P. 2003 Workshop: Chromosome Spatial Clustering Uncovered Through Radiogenic Aberrations

145

AN INTERNAL RADIATION DOSIMETRY COMPUTER PROGRAM, IDAC 2.0, FOR ESTIMATION OF PATIENT DOSES FROM RADIOPHARMACEUTICALS  

Science Journals Connector (OSTI)

......dose to estimate the radiation risk from a diagnostic...grant from the Swedish Radiation Safety Authority [grant number...second-generation personal computer software for internal dose assessment...Radiological Protection. Radiation dose to patients from......

M. Andersson; L. Johansson; D. Minarik; S. Mattsson; S. Leide-Svegborn

2013-12-01T23:59:59.000Z

146

Radiation doses to patients undergoing barium meal and barium enema examinations  

Science Journals Connector (OSTI)

......organ dose determination in radiation hygiene. STUK-A87 Raport, Finish Centre for Radiation and Nuclear Safety (1989). 14. Carroll, E...methods Greece Humans Middle Aged Radiation Dosage Radiometry methods Software...

M. G. Delichas; K. Hatziioannou; E. Papanastassiou; P. Albanopoulou; E. Chatzi; A. Sioundas; K. Psarrakos

2004-07-01T23:59:59.000Z

147

Patient-size-dependent radiation dose optimisation technique for abdominal CT examinations  

Science Journals Connector (OSTI)

......CT dosimetry and radiation safety. Radiol. Soc...Notification. Reducing radiation risk from computed...gov/cdrh/safety/110201-ct...McCollough C. H. Radiation dose in computed...region of interest software available in both......

J. E. Ngaile; P. Msaki; R. Kazema

2012-01-01T23:59:59.000Z

148

Radiation dose survey in a paediatric cardiac catheterisation laboratory equipped with flat-panel detectors  

Science Journals Connector (OSTI)

......investigate the radiation doses delivered...using the PCXMC software. For diagnostic...the E are the radiation field size at...DAP. The PCXMC software calculates organ...Finnish Centre for Radiation and Nuclear Safety. Report No......

O. Dragusin; M. Gewillig; W. Desmet; K. Smans; L. Struelens; H. Bosmans

2008-01-01T23:59:59.000Z

149

Intensity Modulated Radiation Therapy With Dose Painting to Treat Rhabdomyosarcoma  

SciTech Connect

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

Yang, Joanna C.; Dharmarajan, Kavita V. [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States)] [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Wexler, Leonard H. [Department of Pediatrics, Memorial Sloan-Kettering Cancer Center, New York, New York (United States)] [Department of Pediatrics, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); La Quaglia, Michael P. [Department of Surgery, Memorial Sloan-Kettering Cancer Center, New York, New York (United States)] [Department of Surgery, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Happersett, Laura [Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, New York (United States)] [Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Wolden, Suzanne L., E-mail: woldens@mskcc.org [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States)

2012-11-01T23:59:59.000Z

150

Low Dose Radiation Research Program: Assessing Biological Function of DNA  

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

Assessing Biological Function of DNA Damage Response Genes Assessing Biological Function of DNA Damage Response Genes Larry H. Thompson Lawrence Livermore National Laboratory Why This Project To understand the relative importance of individual DNA repair and DNA-damage response pathways to the recovery of mammalian cells after exposure to low doses of ionizing radiation (IR). This understanding may lead to better ways of setting limits on human exposure to IR. In spite of the discovery of many mammalian DNA repair genes, our current knowledge of how many of these genes contribute to cellular recovery from IR exposure is quite limited. Project Goals Measure cellular responses at doses in the 5-100 cGy range, which generally cause changes too small to detect in normal, repair-proficient cells Focus on DNA double-strand breaks (DSBs) and DNA oxidative base

151

Low Dose Radiation Research Program: Quantification of Repair of  

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

Quantification of Repair of Low-Dose-Induced DNA Double-Strand Quantification of Repair of Low-Dose-Induced DNA Double-Strand Breaks in Diploid Human Cells Authors: David Schild,1 and Larry H. Thompson,2 Institutions: 1Life Sciences Division, Lawrence Berkeley National Laboratory; and 2BBR Program, Lawrence Livermore National Laboratory Double-strand breaks (DSBs) are the biochemical lesions of primary concern in radiation related health effects. Compelling evidence from rodent and chicken model systems indicates that homologous recombinational repair (HRR) plays an essential role for cell viability in the repair of spontaneous DSBs arising during DNA replication and an important role in the repair of IR-induced DSBs. IR-induced DSBs are also repaired by error-prone nonhomologous end joining (NHEJ). Using hTERT-immortalized

152

Low-Dose Radiation Cataract and Genetic Determinants of Radiosensitivity  

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

Cataract and Genetic Determinants of Radiosensitivity Cataract and Genetic Determinants of Radiosensitivity Kleiman, N.J. 1 , Smilenov, L.B. 2 , Brenner, D.J. 2 and Hall, E.J. 2 1 Department of Environmental Health Sciences, Mailman School of Public Health & 2 The Center for Radiological Research, College of Physicians & Surgeons, Columbia University, New York 10032 The lens of the eye is one of the most radiosensitive tissues in the body. Ocular ionizing radiation exposure results in characteristic, dose related, progressive lens changes leading to cataract formation. While initial, early stages of such opacification may not cause visual disability, the severity of such changes progressively increases with dose until vision is impaired and cataract extraction surgery may be required. The

153

Population doses from environmental gamma radiation in Iraq  

SciTech Connect

The exposure rates due to external gamma radiation were measured in 11 Iraqi governerates. Measurements were performed with an Environmental Monitoring System (RSS-111) in open air 1 m above the ground. The average absorbed dose rate in each governerate was as follows (number x 10(-2) microGy h-1): Babylon (6.0), Kerbala (5.3), Al-Najaf (5.4), Al-Kadysia (6.5), Wasit (6.5), Diala (6.5), Al-Anbar (6.5), Al-Muthana (6.6), Maisan (6.8), Thee-Kar (6.6), and Al-Basrah (6.5). The collective doses to the population living in these governerates were 499, 187, 239, 269, 262, 458, 384, 153, 250, 450, and 419 person-Sv, respectively.

Marouf, B.A.; Mohamad, A.S.; Taha, J.S.; al-Haddad, I.K. (Iraq Atomic Energy Commission, Nuclear Research Center, Tuwaitha, Baghdad, (Iraq))

1992-05-01T23:59:59.000Z

154

Low Dose Radiation Research Program: Optimizing the Scientific, Regulatory  

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

Optimizing the Scientific, Regulatory and Societal Impact of the DOE Optimizing the Scientific, Regulatory and Societal Impact of the DOE Low Dose Research Program Authors: Antone L. Brooks Institution: Washington State University Tri-Cities Richland, Washington The purpose of this project is to provide a focal point for communication of the research results from the DOE Low Dose Radiation Research Program. The major communication tool provided by this project is a Website at Washington State University. The website is being maintained to provide communication between the scientific advances generated by the research program and scientists both in and outside the program, policy makers, regulators and the public. The website also contains a number of presentations and illustrations that are written so that they will be easy

155

Low Dose Ionizing Radiation Modulates Immune Function New Project Overview  

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

Modulates Immune Function New Project Overview Modulates Immune Function New Project Overview Gregory Nelson Loma Linda University Abstract The immune system provides the first line of defense for exposures to environmental hazards. Protective immunity mechanisms using innate or adaptive responses are employed to mitigate acute challenges or amplify the readiness of the system to respond to future challenges. Some stimuli lead to amplified inflammatory reactions such as delayed hypersensitivity which is required for immunity to parasites and can also lead to adverse consequences such as contact dermatitis. Radiation exposure has the potential to aggravate hypersensitivity reactions as well as to suppress protective immunity. Ionizing radiation at high doses has long been recognized as highly effective in destroying cells of the immune system,

156

Low Dose Radiation Research Program: Computational Modeling of Biochemical  

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

Computational Modeling of Biochemical Pathways Linking Ionizing Computational Modeling of Biochemical Pathways Linking Ionizing Radiation to Cell Cycle Arrest, Apoptosis, and Tumor Incidence Authors: Yuchao Maggie Zhao and Rory Conolly Institutions: Center for Computational Systems Biology CIIT Centers for Health Research Long-Range Goal: To develop an integrated, computational framework for the prediction of low-dose-response to ionizing radiation (IR) in people. Methodology: To provide a flexible framework to evaluate mechanisms of cellular adaptive responses after exposure to IR, three progressively more complicated descriptions of biochemical pathways linking DNA damage with cell-cycle checkpoint control and apoptosis were developed. These descriptions focus on p53-dependent checkpoint arrest and apoptosis, p73-dependent apoptosis, and Chk2-dependent checkpoint arrest,

157

Low Dose Radiation Research Program: Characterizing Bystander Effects  

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

Irradiation. Irradiation. Authors: L.A. Braby and J.R. Ford. Institutions: Texas A&M University. Bystander effects, which are typically seen as in increase in the cellular concentration of specific repair related molecules or as cytogenetic changes which appear to be the consequence of DNA damage, may be a significant factor in the risk of long-term health effects of low doses of radiation. These effects clearly increase the effective size of the target for radiation response, from the diameter of a single cell or cell nucleus to something significantly larger, by bringing additional cells into the process. It is unclear whether this larger target will result in an increase or a decrease in the probability of inducing a change which would be detrimental to the health of the organism, but it clearly reduces the

158

Low Dose Radiation Research Program: Genetic Mechanisms of Induced  

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

Mechanisms of Induced Chromosomal Instability and their Mechanisms of Induced Chromosomal Instability and their Relationships with Radiation Tumorigenesis Robert Ullrich Colorado State University Why This Project A combination of epidemiological, experimental, animal, and cellular molecular data is used in the estimation of tumor risk after low doses of low-LET radiation. Uncertainties are recognized in the interpretation of all these data sets, and recent findings concerning genomic instability in irradiated cells challenge the conventional view that induced DNA damage is expressed during the immediate post-irradiation cell cycle. These data on genomic instability are based largely upon studies of cell cultures the mechanisms involved and implications for tumor formation in living organisms remain unclear. Nevertheless, if induced genomic instability were

159

Low Dose Radiation Research Program: Cooperation Between Homologous  

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

Cooperation Between Homologous Recombination and the Fanconi Anemia Cooperation Between Homologous Recombination and the Fanconi Anemia Cancer Suppressor Proteins in Minimizing Spontaneous and Radiation-Induced Chromosomal Instability Authors: Larry H. Thompson, John M. Hinz, Robert S. Tebbs, and N. Alice Yamada Institutions: Biosciences Directorate, Lawrence Livermore National Laboratory, Livermore, California Purpose and experimental approach. This study addresses the genetic basis of spontaneous mutagenesis as a means of understanding the DNA damage-response pathways that maintain chromosome stability. It is our view that knowledge of these processes is fundamental to understanding how low dose ionizing radiation (IR) produces chromosomal rearrangements that lead to carcinogenesis. Endogenous oxidative DNA damage is presumed to be a

160

The Concentration Of Tritium In Urine And Internal Radiation Dose Estimation Of PTNBR Radiation Workers  

SciTech Connect

The operation of Triga 2000 reactor in Nuclear Technology Center for Materials and Radiometry (PTNBR BATAN) normally produce tritium radionuclide which is the activation product of deuterium atom in reactor primary cooling water. According to previous monitoring, tritium was detected with the concentration of 8.236{+-}0.677 kBq/L and 1.704{+-}0.046 Bq/L in the primary cooling water and in reactor hall air, respectively. The tritium in reactor hall air chronically can be inhaled by the workers. In this research, tritium content in radiation workers' urine was determined to estimate the internal radiation doses received by the workers. About 50-100 mL of urine samples were collected from 48 PTNBR workers that is classified as 24 radiation workers and 24 administration staffs as a control. Urine samples of 25 mL were then prepared by active charcoal and KMnO{sub 4} addition and followed with complete distillation. The 2 mL of distillate was added with 13 mL scintillator, shaked vigorously and remained in cool and dark condition for about 24 hours. The tritium in the samples was then measured using liquid scintillation counter (LSC) for 1 hour. From the measurement results it was obtained that the tritium concentration in the urine of radiation workers were in the range of not detected and 5.191 Bq/mL, whereas in the administration staffs the concentration were between not detected and 4.607 Bq/mL. Internally radiation doses were calculated using the tritium concentration data, and it was found the averages about 0.602 {mu}Sv/year and 0.532 {mu}Sv/year for radiation workers and administration staffs, respectively. The doses received by the workers were lower than that of the permissible doses from tritium, i.e. 40 {mu}Sv/year.

Tjahaja, Poppy Intan; Sukmabuana, Putu; Aisyah, Neneng Nur [PTNBR BATAN, Jl. Tamansari no. 71, Bandung 40132 (Indonesia)

2010-12-23T23:59:59.000Z

Note: This page contains sample records for the topic "radiation dose equivalent" 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

Molecular mechanisms of radiation carcinogenesis and the linear, non-threshold dose response model of radiation risk estimation  

Science Journals Connector (OSTI)

Recent research in molecular radiation carcinogenesis is reviewed with the specific aim of exploring the implications this research may have on the dose response relationship of radiation-induced cancer at low...

K. R. Trott; M. Rosemann

2000-06-01T23:59:59.000Z

162

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

163

Enhancement of natural background gamma-radiation dose around uranium microparticles in the human body  

Science Journals Connector (OSTI)

...photoelectrons. For most ionizing radiations, a large proportion...the absorbed dose is deposited...having a shorter range and being more strongly ionizing close to the...in high local doses, causing damage...enhancement of the radiation dose in volumes...

2010-01-01T23:59:59.000Z

164

The Effects of High Dose Rates of Ionizing Radiations on Solutions of Iron and Cerium Salts  

Science Journals Connector (OSTI)

...research-article The Effects of High Dose Rates of Ionizing Radiations on Solutions of Iron and Cerium...of 1.3 duration and over a range of dose rates from 0.5 to 20 000 rads/pulse. Radiation yields at constant dose rate...

1960-01-01T23:59:59.000Z

165

Monte Carlo estimation of radiation doses during paediatric barium meal and cystourethrography examinations  

Science Journals Connector (OSTI)

Organ doses are important quantities in assessing the radiation risk. In the case of children, estimation of this risk is of particular concern due to their significant radiosensitivity and the greater health detriment. The purpose of this study is to estimate the organ doses to paediatric patients undergoing barium meal and micturating cystourethrography examinations by clinical measurements and Monte Carlo simulation. In clinical measurements, dosearea products (DAPs) were assessed during examination of 50 patients undergoing barium meal and 90 patients undergoing cystourethrography examinations, separated equally within three age categories: namely newborn, 1 year and 5 years old. Monte Carlo simulation of photon transport in male and female mathematical phantoms was applied using the MCNP5 code in order to estimate the equivalent organ doses. Regarding the micturating cystourethrography examinations, the organs receiving considerable amounts of radiation doses were the urinary bladder (1.87, 2.43 and 4.7 mSv, the first, second and third value in the parentheses corresponds to neonatal, 1 year old and 5 year old patients, respectively), the large intestines (1.54, 1.8, 3.1 mSv), the small intestines (1.34, 1.56, 2.78 mSv), the stomach (1.46, 1.02, 2.01 mSv) and the gall bladder (1.46, 1.66, 2.18 mSv), depending upon the age of the child. Organs receiving considerable amounts of radiation during barium meal examinations were the stomach (9.81, 9.92, 11.5 mSv), the gall bladder (3.05, 5.74, 7.15 mSv), the rib bones (9.82, 10.1, 11.1 mSv) and the pancreas (5.8, 5.93, 6.65 mSv), depending upon the age of the child. DAPs to organ/effective doses conversion factors were derived for each age and examination in order to be compared with other studies.

A Dimitriadis; G Gialousis; T Makri; M Karlatira; P Karaiskos; E Georgiou; S Papaodysseas; E Yakoumakis

2011-01-01T23:59:59.000Z

166

Radiation dose and image quality in K-edge subtraction computed tomography of lung in vivo  

Science Journals Connector (OSTI)

Radiation dose dependency of image quality was showed in in vivo rabbit lung images with and without a contrast agent using the synchrotron-radiation-based K-edge subtraction method. Consistency of the theoretical and measured radiation dose rate values was found.

Strengell, S.

2014-10-01T23:59:59.000Z

167

Current status of patient radiation doses from computed tomography examinations in Tanzania  

Science Journals Connector (OSTI)

......the magnitude of radiation dose imparted to...and the CTDOSE software based on NRPB conversion...CT dosimetry and radiation safety. Radiol. Soc...requirements for the safety of X-ray equipment...Tingey, D. R. C. Radiation doses from computed......

J. E. Ngaile; P. Msaki; R. Kazema

2006-12-01T23:59:59.000Z

168

Whole-Body Biodistribution and Estimation of Radiation-Absorbed Doses of the Dopamine D1  

E-Print Network (OSTI)

Whole-Body Biodistribution and Estimation of Radiation-Absorbed Doses of the Dopamine D1 Receptor-SCH-23390 (6,7), and is highly reliable for PET quantification (7). Radiation-absorbed dose estimates of 11C and Behaviour, Monash University, Clayton, Victoria, Australia The present study estimated radiation

Shen, Jun

169

Estimation of radiation doses from 137Cs to frogs in a wetland ecosystem  

Science Journals Connector (OSTI)

Currently, there is no established methodology to estimate radiation doses to non-human biota. Therefore, in this study, various dose models were used to estimate radiation doses to moor frogs (Rana arvalis) in a wetland ecosystem contaminated with 137Cs. External dose estimations were based on activity concentrations of 137Cs in soil and water, considering changes in habitat over a life-cycle. Internal doses were calculated from the activity concentrations of 137Cs measured in moor frogs. Depending on the dose model used, the results varied substantially. External dose rates ranged from 21 to 160 mGy/y, and internal dose rates varied between 1 and 14 mGy/y. Maximum total dose rates to frogs were below the expected safe level for terrestrial populations, but close to the suggested critical dose rate for amphibians. The results show that realistic assumptions in dose models are particularly important at high levels of contamination.

K. Stark; R. Avila; P. Wallberg

2004-01-01T23:59:59.000Z

170

Low Dose Radiation Research Program: Use of Computational Modeling to  

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

Use of Computational Modeling to Evaluate Hypotheses about the Use of Computational Modeling to Evaluate Hypotheses about the Molecular and Cellular Mechanisms of Bystander Effects Authors: Yuchao “Maggie” Zhao and Rory Conolly Institutions: CIIT Centers for Health Research, 6 Davis Drive, Research Triangle Park, North Carolina A detailed understanding of the biological mechanisms of radiation-induced damage at the molecular and cellular levels is needed for accurate assessment of the shape of the dose-response curve for radiationinduced health effects in the intact organism. Computational models can contribute to the improved understanding of mechanisms through integration of data and quantitative evaluation of hypotheses. We propose to develop a novel computational model of bystander effects elicited by oxidative stress and a

171

Measurement of natural radioactivity and dose rate assessment of terrestrial gamma radiation in the soil of southern Punjab, Pakistan  

Science Journals Connector (OSTI)

......terrestrial background radiation mainly due to these...assess the population radiation doses(4-9). However...data are available on naturally occuring and artificial radionulides...order to assess the radiation doses for the general......

I. Fatima; J. H. Zaidi; M. Arif; M. Daud; S. A. Ahmad; S. N. A. Tahir

2008-01-01T23:59:59.000Z

172

Estimation of risk from medical radiation exposure based on effective and organ dose: how much difference is there?  

Science Journals Connector (OSTI)

......Russian Basic Sanitary Radiation Protection Standards...Basic Sanitary Rules for Radiation Safety of 2010(3). It is...CT)(4). Although radiation dose is the primary...effective dose; this software is addressed to radiologists......

V. K. Ivanov; V. V. Kashcheev; S. Yu. Chekin; A. N. Menyaylo; E. A. Pryakhin; A. F. Tsyb; F. A. Mettler

2013-07-01T23:59:59.000Z

173

Effect of incremental doses of radiation on viability of the microbial population on synthetic operating room gowns.  

Science Journals Connector (OSTI)

...manufacturer and peri- 528 RADIATION DOSE AND MICROBIAL VIABILITY...used to calculate the radiation resistances because...SEM does allow an estimation of the number of cells...ENVIRON. MICROBIOL. RADIATION DOSE AND MICROBIAL VIABILITY...

J L Whitby; D G Storey

1982-03-01T23:59:59.000Z

174

Exposure to Low-Dose Ionizing Radiation from Medical Imaging Procedures  

Science Journals Connector (OSTI)

...did not use measures of radiation dose that are specific to the subjects we studied but instead relied on estimates of effective doses, which are neither precisely measured nor subject-specific. The effective dose is a calculated estimate designed to provide a sex-averaged dose for a reference subject... Experimental and epidemiologic evidence has linked exposure to low-dose, ionizing radiation with the development of solid cancers and leukemia.1 As a result, persons at risk for repeated radiation exposure, such as workers in health care and the nuclear ...

Fazel R.; Krumholz H.M.; Wang Y.

2009-08-27T23:59:59.000Z

175

End group characterization in DNA of thymocytes after low doses of ionizing radiation  

Science Journals Connector (OSTI)

Investigations into the configuration of the radiation induced strand breaks in the low dose range are presented. DNA sections containing the radiation induced strand breaks were separated from the undamaged s...

Th. Coquerelle; C. Sexauer

1977-01-01T23:59:59.000Z

176

Estimation of the Radiation Dose to the Public Due to Atmospheric Emissions from the Rostov NPP  

Science Journals Connector (OSTI)

The radiation dose to the public due to atmospheric emissions from the Rostov NPP is calculated using a point conservative approach and a complex of migration and dosimetric models. The radiation exposure path...

L. A. Sharpan; E. I. Karpenko; S. I. Spiridonov

2014-01-01T23:59:59.000Z

177

SFACTOR: a computer code for calculating dose equivalent to a target organ per microcurie-day residence of a radionuclide in a source organ - supplementary report  

SciTech Connect

The purpose of this report is to describe revisions in the SFACTOR computer code and to provide useful documentation for that program. The SFACTOR computer code has been developed to implement current methodologies for computing the average dose equivalent rate S(X reverse arrow Y) to specified target organs in man due to 1 ..mu..Ci of a given radionuclide uniformly distributed in designated source orrgans. The SFACTOR methodology is largely based upon that of Snyder, however, it has been expanded to include components of S from alpha and spontaneous fission decay, in addition to electron and photon radiations. With this methodology, S-factors can be computed for any radionuclide for which decay data are available. The tabulations in Appendix II provide a reference compilation of S-factors for several dosimetrically important radionuclides which are not available elsewhere in the literature. These S-factors are calculated for an adult with characteristics similar to those of the International Commission on Radiological Protection's Reference Man. Corrections to tabulations from Dunning are presented in Appendix III, based upon the methods described in Section 2.3. 10 refs.

Dunning, Jr, D E; Pleasant, J C; Killough, G G

1980-05-01T23:59:59.000Z

178

Plutonium 239 Equivalency Calculations  

SciTech Connect

This document provides the basis for converting actual weapons grade plutonium mass to a plutonium equivalency (PuE) mass of Plutonium 239. The conversion can be accomplished by performing calculations utilizing either: (1) Isotopic conversions factors (CF{sub isotope}), or (2) 30-year-old weapons grade conversion factor (CF{sub 30 yr}) Both of these methods are provided in this document. Material mass and isotopic data are needed to calculate PuE using the isotopic conversion factors, which will provide the actual PuE value at the time of calculation. PuE is the summation of the isotopic masses times their associated isotopic conversion factors for plutonium 239. Isotopic conversion factors are calculated by a normalized equation, relative to Plutonium 239, of specific activity (SA) and cumulated dose inhalation affects based on 50-yr committed effective dose equivalent (CEDE). The isotopic conversion factors for converting weapons grade plutonium to PuE are provided in Table-1. The unit for specific activity (SA) is curies per gram (Ci/g) and the isotopic SA values come from reference [1]. The cumulated dose inhalation effect values in units of rem/Ci are based on 50-yr committed effective dose equivalent (CEDE). A person irradiated by gamma radiation outside the body will receive a dose only during the period of irradiation. However, following an intake by inhalation, some radionuclides persist in the body and irradiate the various tissues for many years. There are three groups CEDE data representing lengths of time of 0.5 (D), 50 (W) and 500 (Y) days, which are in reference [2]. The CEDE values in the (W) group demonstrates the highest dose equivalent value; therefore they are used for the calculation.

Wen, J

2011-05-31T23:59:59.000Z

179

Dosimetric Comparison of High-Dose-Rate Brachytherapy and Intensity-Modulated Radiation Therapy as a Boost to the Prostate  

SciTech Connect

Purpose: We compared the dose conformity of two radiation modalities: high-dose-rate brachytherapy (HDR BT) and intensity-modulated radiation therapy (IMRT) to deliver a boost to the prostate after external beam radiotherapy (EBRT). Methods and Materials: Ten successive patients with prostate adenocarcinoma treated with a single 10-Gy HDR BT boost after EBRT were investigated. Four theoretical IMRT plans were computed: (a) 32.85 Gy IMRT and (b) 26 Gy IMRT with CTV-PTV expansions, doses corresponding to the equivalent dose in 2-Gy fractions (EQD2) of one 10-Gy fraction calculated with a prostate alpha/beta ratio of respectively 1.5 and 3 Gy; and (c) 32.85 Gy IMRT and (d) 26 Gy IMRT without CTV-PTV expansions. The dose-volume histogram values converted in EQD2 with an alpha/beta ratio of 3 Gy for the organs at risk were compared. Results: The HDR BT plan delivered higher mean doses to the PTV compared with IMRT plans. In all, 33% of the rectal volume received a mean dose of 5.32 +- 0.65 Gy and 20% of bladder volume received 4.61 +- 1.24 Gy with HDR BT. In comparison, doses delivered with IMRT were respectively 13.4 +- 1.49 Gy and 10.81 +- 4 Gy, even if only 26 Gy was prescribed to the PTV with no CTV-PTV expansion (p < 0.0001). The hot spots inside the urethra were greater with HDR BT but acceptable. Conclusions: Use of HDR BT produced a more conformal plan for the boost to the prostate than IMRT even without CTV-PTV expansions.

Hermesse, Johanne, E-mail: jhermesse@chu.ulg.ac.b [Department of Radiation Oncology, Liege University Hospital, Liege (Belgium); Biver, Sylvie; Jansen, Nicolas [Department of Radiation Oncology, Liege University Hospital, Liege (Belgium); Lenaerts, Eric [Department of Medical Physics, Liege University Hospital, Liege (Belgium); Nickers, Philippe [Department of Radiation Oncology, Oscar Lambret Center, Lille (France)

2010-01-15T23:59:59.000Z

180

Typical Radiation Doses to Patients from Some Common X Ray Examinations in Tanzania  

Science Journals Connector (OSTI)

...Radiation Protection Dosimetry Article Typical Radiation Doses to Patients from Some Common X Ray Examinations in Tanzania W.E. Muhogora A.M. Nyanda U.S. Lema J.E. Ngaile The results of entrance surface dose measurements on adult patients......

W.E. Muhogora; A.M. Nyanda; U.S. Lema; J.E. Ngaile

1999-04-01T23:59:59.000Z

Note: This page contains sample records for the topic "radiation dose equivalent" 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

Estimation of internal radiation dose from both immediate releases and continued  

Science Journals Connector (OSTI)

A brief description is provided of the basic concepts related to 'internal dose' and how it differs from doses that result from radioactive materials and direct radiation outside of the body. The principles of radiation dose reconstruction, as applied to both internal and external doses, are discussed on the basis of a recent publication prepared by the US National Council on Radiation Protection and Measurements. Finally, ideas are introduced related to residual radioactive contamination in the environment that has resulted from the releases from damaged reactors and also to the management of wastes that may be generated in both regional cleanup and decommissioning of the Fukushima nuclear power plant.

Bruce Napier

2012-01-01T23:59:59.000Z

182

Low Dose Radiation Research Program: Comparison of DNA Damage Risk from  

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

Comparison of DNA Damage Risk from Low-Dose Radiation and Folate Comparison of DNA Damage Risk from Low-Dose Radiation and Folate Deficiency. Authors: Chantal Courtemanche, Arnold C. Huang, Nicole Kerry, Bernice Ng, and Bruce N. Ames. Institutions: Children’s Hospital Oakland Research Institute, Oakland, California. Our overall goal is to understand and quantify the real effects of low-dose radiation by measuring direct and specific cellular changes. However, since the background dose of radiation to which most individuals are exposed is well below the levels where significant biological effects, such as mutation or tumor induction, are observed, our novel approach is to compare the consequences of radiation to those of specific nutritional deficiencies. By determining which of these two common stresses at physiologically relevant doses leads to a greater amount of DNA damage, we

183

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

184

Low Dose Radiation Research Program: Research Highlights - 2010  

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

DNA Double-Strand Break Repair Capacities Before and After Exposure to Low DNA Double-Strand Break Repair Capacities Before and After Exposure to Low Dose Radiation Immunochemical detection of DSB foci in the nuclei of human fibroblasts. (A) γ-H2AX phospho-serine 139 foci (chromatin marker of DSBs; green). (B) ataxia-telangiectasia mutated phospho-serine 1981 foci (ATM, DNA damage-responsive kinase; red). (C) Merge of images A and B. (White arrows mark large γ-H2AX foci and coincident γ-H2AX/pATM foci that were positively scored; yellow arrows mark small γ-H2AX foci that lack corresponding pATM foci that were not scored.) Enlarge Image Immunochemical detection of DSB foci in the nuclei of human fibroblasts. (A) γ-H2AX phospho-serine 139 foci (chromatin marker of DSBs; green). (B) ataxia-telangiectasia mutated phospho-serine 1981 foci (ATM,

185

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

SciTech Connect

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

Bedford, Joel

2014-04-18T23:59:59.000Z

186

Alteration of cytokine profiles in mice exposed to chronic low-dose ionizing radiation  

Science Journals Connector (OSTI)

While a high-dose of ionizing radiation is generally harmful and causes damage to living organisms, a low-dose of radiation has been shown to be beneficial in a variety of animal models. To understand the basis for the effect of low-dose radiation in vivo, we examined the cellular and immunological changes evoked in mice exposed to low-dose radiation at very low (0.7mGy/h) and low (3.95mGy/h) dose rate for the total dose of 0.2 and 2Gy, respectively. Mice exposed to low-dose radiation, either at very low- or low-dose rate, demonstrated normal range of body weight and complete blood counts. Likewise, the number and percentage of peripheral lymphocyte populations, CD4+ T, CD8+ T, B, or NK cells, stayed unchanged following irradiation. Nonetheless, the sera from these mice exhibited elevated levels of IL-3, IL-4, leptin, MCP-1, MCP-5, MIP-1?, thrombopoietin, and VEGF along with slight reduction of IL-12p70, IL-13, IL-17, and IFN-?. This pattern of cytokine release suggests the stimulation of innate immunity facilitating myeloid differentiation and activation while suppressing pro-inflammatory responses and promoting differentiation of nave T cells into T-helper 2, not T-helper 1, types. Collectively, our data highlight the subtle changes of cytokine milieu by chronic low-dose ?-radiation, which may be associated with the functional benefits observed in various experimental models.

Suk Chul Shin; Kyung-Mi Lee; Yu Mi Kang; Kwanghee Kim; Cha Soon Kim; Kwang Hee Yang; Young-Woo Jin; Chong Soon Kim; Hee Sun Kim

2010-01-01T23:59:59.000Z

187

Apoptosis as a Mechanism for Low Dose Radiation-and Amifostine-Mediated  

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

Apoptosis as a Mechanism for Low Dose Radiation- and Amifostine-Mediated Apoptosis as a Mechanism for Low Dose Radiation- and Amifostine-Mediated Chromosomal Inversion Responses Pam Sykes Flinders University and Medical Centre Abstract Low dose radiation and the chemical radioprotector amifostine have both been shown to protect cells from the immediate and delayed effects of radiation exposure. They display a number of distinct similarities including their ability to protect cells against radiation-induced DNA damage, radiation-induced cell death and metastases formation. Amifostine, which protects cells from the toxic effects of ionizing radiation, has a broad range of activities including free radical scavenging, polyamine-like DNA binding, and induction of hypoxia and redox-regulated genes. Amifostine’s ability to protect cells is often

188

Extremely Low Dose Ionizing Radiation Up-regulates CXC Chemokines in Normal Human Fibroblasts  

Science Journals Connector (OSTI)

...Research Center for Radiation Safety, National...263-8555 Chiba, Japan. Phone: 81-43-206-3159...doses of ionizing radiation (5). A recent...study showed that Japan has the worlds highest...Research Center for Radiation Safety, National...Inage, Chiba, Japan. fujimora@nirs...

Akira Fujimori; Ryuichi Okayasu; Hiroshi Ishihara; Satoshi Yoshida; Kiyomi Eguchi-Kasai; Kumie Nojima; Satoru Ebisawa; and Sentaro Takahashi

2005-11-15T23:59:59.000Z

189

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

SciTech Connect

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

McMahon, Stephen J., E-mail: stephen.mcmahon@qub.ac.uk [Centre for Cancer Research and Cell Biology, Queen's University Belfast, Belfast, Northern Ireland (United Kingdom); McGarry, Conor K. [Centre for Cancer Research and Cell Biology, Queen's University Belfast, Belfast, Northern Ireland (United Kingdom); Radiotherapy Physics, Northern Ireland Cancer Centre, Belfast Health and Social Care Trust, Belfast, Northern Ireland (United Kingdom); Butterworth, Karl T. [Centre for Cancer Research and Cell Biology, Queen's University Belfast, Belfast, Northern Ireland (United Kingdom); O'Sullivan, Joe M. [Centre for Cancer Research and Cell Biology, Queen's University Belfast, Belfast, Northern Ireland (United Kingdom); Clinical Oncology, Northern Ireland Cancer Centre, Belfast Health and Social Care Trust, Belfast, Northern Ireland (United Kingdom); Hounsell, Alan R. [Centre for Cancer Research and Cell Biology, Queen's University Belfast, Belfast, Northern Ireland (United Kingdom); Radiotherapy Physics, Northern Ireland Cancer Centre, Belfast Health and Social Care Trust, Belfast, Northern Ireland (United Kingdom); Prise, Kevin M. [Centre for Cancer Research and Cell Biology, Queen's University Belfast, Belfast, Northern Ireland (United Kingdom)

2013-12-01T23:59:59.000Z

190

The assessment of the absorbed dose of radiation around a nuclear fuel manufacturing plant  

Science Journals Connector (OSTI)

The estimation of the absorbed dose of radiation by the public around a nuclear plant is a substantial issue for nuclear industries and serves as an essential factor in radiation protection. In this study, the absorbed dose of radiation by the individuals living around a nuclear fuel manufacturing plant was calculated. The Atomic Force Microscopy (AFM) code, which is the generalised version of the AIREM program manual a computer code for calculating doses, population doses, and ground depositions due to atmospheric emissions of radionuclides was used to investigate the following pathways: cloud immersion, ground deposition, inhalation and ingestion. The study was carried out in 16 geographical directions over an 80 km radius. The experimental results demonstrate that the maximum dose is absorbed at 800 m distance from the nuclear plant stack in the east southeast (ESE) direction and is equal to 3.7 10 ?Sv, which is negligible in comparison with the background radiation.

Seyed Mahmoud Reza Aghamiri; Neda Bostani; Manuchehr Roshanzamir

2009-01-01T23:59:59.000Z

191

Radiation Doses to Members of the U.S. Population from Ubiquitous Radionuclides in the Body: Part 2, Methods and Dose Calculations  

SciTech Connect

This paper is part two of a three-part series investigating annual effective doses to residents of the United States from intakes of ubiquitous radionuclides, including radionuclides occurring naturally, radionuclides whose concentrations are technologically enhanced, and anthropogenic radionuclides. This series of papers explicitly excludes intakes from inhaling 222Rn, 220Rn, and their short-lived decay products; it also excludes intakes of radionuclides in occupational and medical settings. Part one reviewed, summarized, characterized, and grouped all published and some unpublished data for U.S. residents on ubiquitous radionuclide concentrations in tissues and organs. Assumptions about equilibrium with long-lived parents are made for the 28 other radionuclides in these series lacking data. This paper describes the methods developed to group the collected data into source regions described in the Radiation Dose Assessment Resource (RADAR) dosimetric methodology. Methods for converting the various units of data published over 50 years into a standard form are developed and described. Often, meaningful values of uncertainty of measurements were not published so that variability in data sets is confounded with measurement uncertainty. A description of the methods developed to estimate variability is included in this paper. The data described in part one are grouped by gender and age to match the RADAR dosimetric phantoms. Within these phantoms, concentration values are grouped into source tissue regions by radionuclide, and they are imputed for source regions lacking tissue data. Radionuclide concentrations are then imputed for other phantoms source regions with missing concentration values, and the uncertainties of the imputed values are increased. The content concentrations of hollow organs are calculated, and activities are apportioned to the bone source regions using assumptions about each radionuclides bone-seeking behavior. The data sets are then ready to be used to estimate equivalent doses to target tissues from these source regions. The target tissues are then mapped to lists of tissues with International Commission on Radiation Protection (ICRP) tissue weighting factors, or they are mapped to surrogate tissue regions when there is no direct match. Effective doses, using ICRP tissue weighting factors recommended in 1977, 1990, and 2007, are calculated from tissue and organ equivalent doses.

Watson, David J.; Strom, Daniel J.

2011-02-25T23:59:59.000Z

192

Estimation of background radiation doses for the Peninsular Malaysias population by ESR dosimetry of tooth enamel  

Science Journals Connector (OSTI)

It is worth mentioning that the background dose is required in evaluating a tooths excess dose of radiation workers or individuals accidentally exposed to radiation, by subtracting the background level of a give...

Mohd Rodzi; Kassym Zhumadilov; Megu Ohtaki

2011-08-01T23:59:59.000Z

193

Low Dose Radiation Research Program: Communicating the Science of the Low  

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

Communicating the Science of the Low Dose Radiation Research Program Communicating the Science of the Low Dose Radiation Research Program Authors: John S. Wassom, Elizabeth T. Owens, Sheryl A. Martin, Amy K. Wolfe, Margaret K. Lyday,* and Susan L. Dimmick** Institutions: Oak Ridge National Laboratory, *Keener Communications, and the **University of Tennessee Graduate School of Medicine. Summary The project team developed a communications plan based on an explicit communications strategy. The plan presents a set of strategic goals, identifies categories of stakeholders relevant to the program, and suggests methods that can be used to achieve strategic goals and reach targeted stakeholders. Context is key to the communication plan. Providing contextual information about low dose radiation, radiation biology, and Low Dose Radiation

194

Annual report shows potential INL radiation dose well below safe regulatory  

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

Annual report shows potential INL radiation dose well below safe Annual report shows potential INL radiation dose well below safe regulatory limits Annual report shows potential INL radiation dose well below safe regulatory limits August 9, 2011 - 12:00pm Addthis Media Contact Tim Jackson, DOE-Idaho Operations Office 208-526-8484 The U.S. Department of Energy's Idaho Operations Office reported this month that radiation from the site falls well below limits established by the U.S. Environmental Protection Agency. The annual report's conclusions are supported by direct environmental monitoring data routinely taken during the year, and show that activities at the Idaho National Laboratory (INL) site are protective of human health and the environment. Data shows that the INL site potential radiation dose is less than 1% of

195

Benchmarking and validation of a Geant4-SHADOW Monte Carlo simulation for dose calculations in microbeam radiation therapy  

Science Journals Connector (OSTI)

Benchmarking and validation of a new Monte Carlo code for dose calculations in microbeam radiation therapy are described.

Cornelius, I.

2014-04-03T23:59:59.000Z

196

Low Dose Radiation | U.S. DOE Office of Science (SC)  

Office of Science (SC) Website

Radiobiology: Low Dose Radiation Radiobiology: Low Dose Radiation Research Biological and Environmental Research (BER) BER Home About Research Research Abstracts Searchable Archive of BER Highlights External link Biological Systems Science Division (BSSD) Genomic Science DOE Bioenergy Research Centers Radiochemistry & Imaging Instrumentation Radiobiology: Low Dose Radiation Research DOE Human Subjects Protection Program Structural Biology DOE Joint Genome Institute Climate and Environmental Sciences Division (CESD) Facilities Science Highlights Benefits of BER Funding Opportunities Biological & Environmental Research Advisory Committee (BERAC) News & Resources Contact Information Biological and Environmental Research U.S. Department of Energy SC-23/Germantown Building 1000 Independence Ave., SW Washington, DC 20585 P: (301) 903-3251 F: (301)

197

Low dose ionizing radiation produces too few reactive oxygen species to directly affect antioxidant concentrations in cells  

Science Journals Connector (OSTI)

...Radiolysis products and internal dose distribution - Calculation of...products and internal distribution of doses Low dose ionizing radiation produces too few reactive oxygen...stress is the mechanism for a wide range of negative impacts on biota living...

2012-01-01T23:59:59.000Z

198

Relative age-specific radiation dose commitment factors for major radionuclides released from nuclear fuel facilities  

SciTech Connect

During the licensing process for nuclear fuel facilities, committed dose equivalents must be calculated for potential exposures to people in the area around these facilities. These committed dose equivalents are usually calculated from tabulated dose-conversion factors that convert the quantity of radioactive material potentially taken in by individuals through ingestion or inhalation. For calculating committed dose equivalents to children, the Nuclear Regulatory Commission has in the past appealed to age-specific dose-conversion factors listed in NUREG-0172 (1977), which is based on a computational methodology found in ICRP Publication 2 (1959). Since the publication of NUREG-0172 new models and new concepts of risk have been provided in ICRP Publications 26 and 30 (1977, 1979). These documents provide a detailed methodology for calculating dose-conversion factors for the various radionuclides for an adult reference man. In this report are tabulated age-specific dose-conversion factors, given as multiples of the adult values, for inhalation or ingestion of each of the following isotopes: U-234, U-235, U-238, Th-228, Th-230, Th-232, Ra-226, Ra-228, Pb-210, or Po-210. Our methodology is consistent as far as practical with that of ICRP Publications 26 and 30, but we have modified and extended the ICRP methodology as necessary to include age dependence and to include metabolic and dosimetric information that has been developed since the issuance of these ICRP documents.

Cristy, M.; Leggett, R.W.; Dunning, D.E. Jr.; Eckerman, K.F.

1986-06-01T23:59:59.000Z

199

Total dose radiation response of plasma-damaged NMOS devices  

SciTech Connect

Plasma-damaged NMOS devices were subjected to the X-ray total dose irradiation. Unlike the traditional hot-carrier or Fowler-Nordheim (F-N) stress where the hole trap generation is less pronounced, this study shows enhanced hole trap and interface trap generation on plasma-damaged devices after total dose irradiation.

Yue, J.; Lo, E.; Flanery, M. [Honeywell Solid-State Electronic Center, Plymouth, MN (United States)] [Honeywell Solid-State Electronic Center, Plymouth, MN (United States)

1997-11-01T23:59:59.000Z

200

33. Radioactivity and radiation protection 1 33. RADIOACTIVITY AND RADIATION PROTECTION  

E-Print Network (OSTI)

a conservative estimate for the value of the protection quantity. · Ambient dose equivalent, H(10) (unit: sievert): The dose equivalent at a point in a radiation field that would be produced by the corresponding expanded33. Radioactivity and radiation protection 1 33. RADIOACTIVITY AND RADIATION PROTECTION Revised

Note: This page contains sample records for the topic "radiation dose equivalent" 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.


201

LOW DOSE PHOTON RADIATION-INDUCED CHANGES IN T HELPER LYMPHOCYTES  

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

LOW DOSE PHOTON RADIATION-INDUCED CHANGES IN T HELPER LYMPHOCYTES LOW DOSE PHOTON RADIATION-INDUCED CHANGES IN T HELPER LYMPHOCYTES Daila S. Gridley 1,2 , Asma Rizvi 2 , Xian Luo 1 , Adeola Y. Makinde 2 , Steve Rightnar 1 , Jian Tian 1 , Melba L. Andres 1 , James M. Slater 1 , and Michael J. Pecaut 1,2 Departments of 1 Radiation Medicine and 2 Biochemistry & Microbiology Loma Linda University and Medical Center, Loma Linda, CA 92354 USA Health risks due to protracted low dose irradiation remain unclear. This project investigates T helper (Th) lymphocyte function and the cellular milieu in which they reside under conditions of low dose, low- linear energy transfer (LET) radiation exposure. The Th cells are important because they secrete cytokines essential for generating optimal immune defenses against tumor, virus-infected, and other

202

Radiation dose profile in 125I brachytherapy: an 8-year review  

Science Journals Connector (OSTI)

......KFSHRC is well known in the Kingdom to specialise in cancer treatment using both radiation therapy and brachytherapy...using the IAEA rod phantom and an Eberline DNS-26 depleted uranium standard reference source with a known absorbed dose......

A. N. Al-Haj; A. M. Lobriguito; C. S. Lagarde

2004-08-01T23:59:59.000Z

203

Estimation of the committed radiation dose resulting from gamma radionuclides ingested with food  

Science Journals Connector (OSTI)

The objective of the study was to estimate the value of the radiation dose absorbed in consequence of consumption of popular food products for individual age groups. Potatoes, corn and sugar beet were selected...

Piotr Gody?; Agnieszka Do?ha?czuk-?rdka

2014-03-01T23:59:59.000Z

204

Image Estimation from Marker Locations for Dose Calculation in Prostate Radiation Therapy  

Science Journals Connector (OSTI)

Tracking implanted markers in the prostate during each radiation treatment delivery provides an accurate approximation of prostate location, which enables the use of higher daily doses with tighter margins of ...

Huai-Ping Lee; Mark Foskey; Josh Levy

2010-01-01T23:59:59.000Z

205

Low Dose Radiation Research Program: Identification of Mouse Genetic  

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

Mouse Genetic Susceptibility to Radiation Carcinogenesis Mouse Genetic Susceptibility to Radiation Carcinogenesis Allan Balmain University of California, San Francisco San Francisco, CA. (Jointly funded by NASA and DOE) Why this Project? To identify pathways that control genetic susceptibility to radiation-induced DNA damage and tumor development using novel developments in genomics together with mouse genetics. Project Goals To identify genetic loci that trigger rapid tumor development of mice after radiation. To characterize new genes at these loci that act as tumor suppressor genes or oncogenes. Experimental Approach New candidate-radiation susceptibility genes will be identified using a unique haplotyping approach. Using DNA from radiation-induced lymphoma, changes in the gene copy number can be detected using BAC microarrays. The

206

A new water-equivalent 2D plastic scintillation detectors array for the dosimetry of megavoltage energy photon beams in radiation therapy  

SciTech Connect

Purpose: The objective of this work is to present a new 2D plastic scintillation detectors array (2D-PSDA) designed for the dosimetry of megavoltage (MV) energy photon beams in radiation therapy and to characterize its basic performance. Methods: We developed a 2D detector array consisting of 781 plastic scintillation detectors (PSDs) inserted into a plane of a water-equivalent phantom. The PSDs were distributed on a 26 x 26 cm{sup 2} grid, with an interdetector spacing of 10 mm, except for two perpendicular lines centered on the detection plane, where the spacing was 5 mm. Each PSD was made of a 1 mm diameter by 3 mm long cylindrical polystyrene scintillating fiber coupled to a clear nonscintillating plastic optical fiber. All of the light signals emitted by the PSDs were read simultaneously with an optical system at a rate of one measurement per second. We characterized the performance of the optical system, the angular dependency of the device, and the perturbation of dose distributions caused by the hundreds of PSDs inserted into the phantom. We also evaluated the capacity of the system to monitor complex multileaf collimator (MLC) sequences such as those encountered in step-and-shoot intensity modulated radiation therapy (IMRT) plans. We compared our results with calculations performed by a treatment planning system and with measurements taken with a 2D ionization chamber array and with a radiochromic film. Results: The detector array that we developed allowed us to measure doses with an average precision of better than 1% for cumulated doses equal to or greater than 6.3 cGy. Our results showed that the dose distributions produced by the 6-MV photon beam are not perturbed (within {+-}1.1%) by the presence of the hundreds of PSDs located into the phantom. The results also showed that the variations in the beam incidences have little effect on the dose response of the device. For all incidences tested, the passing rates of the gamma tests between the 2D-PSDA and the treatment planning system were higher than 97.5% when the standard clinical tolerances of 3% or 3 mm were used. Excellent agreement was obtained between the doses measured and calculated when we used the 2D-PSDA for monitoring a MLC sequence from a step-and-shoot IMRT plan. Conclusions: We demonstrated the feasibility of using a large number of PSDs in a new 2D-PSDA for the dosimetry of MV energy photon beams in radiation therapy. The excellent precision, accuracy, and low angular dependence of the device indicate that such a prototype could potentially be used as a high-accuracy quality assurance tool for IMRT and arc therapy patient plan verification. The homogeneity and water-equivalence of the prototype we built suggest that this technology could be extended to multiple detection planes by arranging the fibers into more complex orientations, opening the possibility for 3D dosimetry with PSDs.

Guillot, Mathieu; Beaulieu, Luc; Archambault, Louis; Beddar, Sam; Gingras, Luc [Departement de Physique, de Genie Physique et d'Optique, Universite Laval, Quebec, Quebec G1K 7P4 (Canada) and Departement de Radio-Oncologie, Hotel-Dieu de Quebec, Centre Hospitalier Universitaire de Quebec, Quebec, Quebec G1R 2J6 (Canada); Department of Radiation Physics, Unit 94, University of Texas MD Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, Texas 77030 (United States); Departement de Physique, de Genie Physique et d'Optique, Universite Laval, Quebec, Quebec G1K 7P4 (Canada) and Departement de Radio-Oncologie, Hotel-Dieu de Quebec, Centre Hospitalier Universitaire de Quebec, Quebec, Quebec G1R 2J6 (Canada)

2011-12-15T23:59:59.000Z

207

Genetic susceptibility to low-dose ionizing radiation in the mouse mammary  

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

Genetic susceptibility to low-dose ionizing radiation in the mouse mammary Genetic susceptibility to low-dose ionizing radiation in the mouse mammary gland as a means of understanding human risk for breast cancer Antoine M. Snijders Lawrence Berkeley National Laboratory Abstract Goal: Our goal is to develop an in vivo mechanistic model of genetic variation in the low-dose damage responses of mammary glands using inbred mice known to vary in their sensitivity to low-dose induced mammary gland cancer, and to develop molecular predictors for susceptibility or resistance to low-dose induced breast cancer. Background and Significance: It is increasingly believed that individuals differ in their genetic susceptibilities to environmental insults for diseases such as cancer. This concern is especially important for the large numbers of individuals receiving low-dose exposures in the nuclear energy

208

Low Dose Radiation Research Program: A Variable Energy Soft X-ray  

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

Variable Energy Soft X-ray Microprobe to Investigate Mechanisms of the Variable Energy Soft X-ray Microprobe to Investigate Mechanisms of the Radiation-Induced Bystander Effect Melvyn Folkard Gray Cancer Institute Why This Project The aim of this project is to determine the effects of low radiation doses using a machine that makes it possible to radiate one cell at a time. Our soft X-ray microprobe can irradiate individual cells, or locations within cells with defined doses and with sub-micron precision. We can use low doses approaching that of a single electron track, which is of relevance to environmental level exposures. Much of our work is concentrating on irradiating specified individual cells within cell populations to identify "bystander responses" where non-radiated cells respond to signals from nearby radiated cells. Higher energy x-rays are being generated to extend

209

Low Dose Radiation Research Program: Using a Low LET Electron Microbeam to  

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

a Low LET Electron Microbeam to Investigate Non-Targeted Effects of a Low LET Electron Microbeam to Investigate Non-Targeted Effects of Low Dose Radiation William F. Morgan Radiation Oncology Research Laboratory, Pacific Northwest National Laboratory Why this Project? To examine genomic instability and bystander effects as non-targeted effects associated with low dose radiation exposure. Project Goals To provides a robust, reliable, highly sensitive assay for detecting delayed events occurring in cells exposed to low doses of ionizing radiation. Experimental Approach To mimic radiation damage from gamma and x-ray sources, a low-LET electron microbeam that generates energetic electrons has been designed such that high-energy electrons deposit energy in a pre-selected subset of cells leaving neighboring cells unirradiated. Using a novel green fluorescence gene (GFP) reporter assay, a high through

210

Targeted and Nontargeted Effects of Low-Dose Ionizing Radiation on Delayed Genomic Instability in Human Cells  

Science Journals Connector (OSTI)

...humans receive some radiation exposure, mostly...risks associated with radiation exposure come from populations exposed to ionizing radiation, primarily from epidemiologic...However, those doses, in the range of 0.2 to 2.5...

Lei Huang; Perry M. Kim; Jac A. Nickoloff; and William F. Morgan

2007-02-01T23:59:59.000Z

211

Radiation dose reduction and image enhancement in biological imaging through equally-sloped tomography  

E-Print Network (OSTI)

Iterative reconstruction algorithm Radiation dose reduction Image enhancement Computed tomography a b s t r-dose data acquisi- tion schemes have made it possible to record multiple projections quickly without-energy electrons (Henderson, 1995), which limits the number of projections that can be acquired. Furthermore

Miao, Jianwei "John"

212

Determination of the transuranic dose equivalent to the Rongelapese from urinary output analyzed by the fission track method  

E-Print Network (OSTI)

on metabolic data for plutonium were used to estimate intake, and were generated by INDOS, a computer code used for internal dosimetry calcuiations. The period of intake was assumed to be equal to the time of residence on the island. Effective dose... from exposure to cesium-137. The cesium dose was determined to be higher for older members of the population, but no correlation to plutonium results was found after data analysis. ACKNOWLEDGEMENTS I wish to express my sincere appreciation...

Taylor, George Anthony

1989-01-01T23:59:59.000Z

213

Low Dose Radiation Research Program: Impact of Genetic Factors on the  

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

Genetic Factors on the Heritable Effects of Paternal Exposure to Genetic Factors on the Heritable Effects of Paternal Exposure to Low-Dose Radiation Janet E. Baulch University of California, Davis Why This Project? There is concern about the possible genetic effects of low dose radiation exposure. As a result, much effort has gone towards understanding mutation of cells due to radiation exposure. While recognition of the potential for mutation from exposure to ionizing radiation has led to extensive research, less effort has been given to the possible delayed risk of radiation exposure transmitted to the offspring of the exposed parent. Data from animal models show that parental exposures to DNA-damaging agents, such as ionizing radiation, predispose the offspring to serious health effects, including cancer offspring. Additionally, data from both humans and animal

214

Effects of low-dose radiation on immune cell function using genetic and  

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

low-dose radiation on immune cell function using genetic and low-dose radiation on immune cell function using genetic and metabolomics approaches Henghong Li Georgetown University Abstract The objectives of this study are to investigate acute and persistent effects of ionizing radiation and space radiation on immune cell subsets and function. The role(s) for p38 MAP kinase in such radiation responses is being investigated using a genetic approach where an engineered mouse line has had one wt p38α gene replaced with a dominantnegative mutant (p38α+/DN). T cells are one of the most radiosensitive cell types in vivo, and radiation is known to impact CD4 T cell function long term. T cells are normally activated by antigen, which triggers differentiation to specific subsets involving various cytokines. In addition, T cells have a

215

Low Dose Radiation Research Program: Gregory A. Kimmel  

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

Gregory A. Kimmel Gregory A. Kimmel Pacific Northwest National Laboratory Past Project A Novel Spatially Resolved Cell Irradiator to Study Bystander and Adaptive Responses to Low-LET Radiation. Technical Abstracts 2002 Workshop: Spatially Resolved Single Cell Irradiator to Study Bystander Responses to Low LET Radiation. Resat, M.S., Kimmel, G.A., Miller, J.H., McDonald, J.C., Murphy, M.K., Strom, D.J., Thrall, B.D., and Colson, S.D. 2001 Workshop: Spatially Resolved Single Cell Irradiator to Study Bystander Responses to Low LET Radiation. Resat, M.S., Kimmel, G.A., Miller, J.H., McDonald, J.C., Murphy, M.K., Strom, D.J., Thrall, B.D., Metting, N.F., and Colson, S.D 1999 Workshop: A Novel, Spatially Resolved Cell Irradiator to Study Bystander and Adaptive Responses to Low-LET Radiation.

216

Low Dose Radiation Research Program: Howard L. Liber  

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

Howard L. Liber Howard L. Liber Department of Environmental and Radiological Health Sciences Colorado State University Currently Funded Projects Molecular Mechanisms of Radiation-Induced Genomic Instability in Human Cells Technical Abstracts 2003 Workshop: Delayed genomic instability in human lymphoblasts exposed to 137Cs y-rays radiation Schwartz, J.L., Jordan, R., Lenarczyk, M. and Liber, H.L. 2002 Workshop: Molecular Mechanisms of Radiation-Induced Genomic Instability in Human Cells. Liber, H.L. and Schwartz, J.L. Publications Zhang, Y., Zhou, J., Held, K.D., Redmond, R.W., Prise, K.M., and Liber, H.L. (2008). Deficiencies of double-strand break repair factors and effects on mutagenesis in directly [gamma]-irradiated and medium-mediated bystander human lymphoblastoid cells. Radiation Research 169(2):197-206.

217

Dose-Rate Dependence of High-Dose Health Effects in Humans from Photon Radiation with Application to Radiological Terrorism  

SciTech Connect

In 1981, as part of a symposium entitled ''The Control of Exposure of the Public to Ionizing Radiation in the Event of Accident or Attack,'' Lushbaugh, H?bner, and Fry published a paper examining ''radiation tolerance'' of various human health endpoints as a function of dose rate. This paper may not have received the notice it warrants. The health endpoints examined by Lushbaugh et al. were the lethal dose that will kill 50% of people within 60 days of exposure without medical care (LD50/60); severe bone marrow damage in healthy men; severe bone marrow damage in leukemia patients; temporary sterility (azoospermia); reduced male fertility; and late effects such as cancer. Their analysis was grounded in extensive clinical experience and anchored to a few selected data points, and based on the 1968 dose-rate dependence theory of J.L. Bateman. The Lushbaugh et al. paper did not give predictive equations for the relationships, although they were implied in the text, and the relationships were presented in a non-intuitive way. This work derives the parameters needed in Bateman's equation for each health endpoint, tabulates the results, and plots them in a more conventional manner on logarithmic scales. The results give a quantitative indication of how the human organism can tolerate more radiation dose when it is delivered at lower dose rates. For example, the LD50/60 increases from about 3 grays (300 rads) when given at very high dose rates to over 10 grays (1,000 rads) when given at much lower dose rates over periods of several months. The latter figure is borne out by the case of an individual who survived for at least 19 years after receiving doses in the range of 9 to 17 grays (900-1700 rads) over 106 days. The Lushbaugh et al. work shows the importance of sheltering when confronted with long-term exposure to radiological contamination such as would be expected from a radiological dispersion event, reactor accident, or ground-level nuclear explosion.

Strom, Daniel J.

2005-01-14T23:59:59.000Z

218

Annexin A2 Regulates A Low Dose-Specific Stress Response To Radiation.  

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

Annexin A2 Regulates A Low Dose-Specific Stress Response To Radiation. Thomas J. Annexin A2 Regulates A Low Dose-Specific Stress Response To Radiation. Thomas J. Weber (PI), Greg J. Newton, Ryan D. Quesenberry, Janani I. Shutthanandan, Nikki Bollinger, Heather E. Engelmann and Lee K. Opresko. Cell Biology and Biochemistry Group, Pacific Northwest National Laboratory, Richland, WA 99354. Previous studies have demonstrated that JB6 cells release cell transforming paracrine factors following exposure to a low dose of radiation (10 cGy). Investigation of secreted proteins by SDS-Page and silver stain led to the identification of a 36 kDa band whose levels were increased in medium from irradiated cells, relative to sham controls. The 36 kDa band was identified as annexin A2 by mass spectrometry. Western blot analysis confirmed a dose-dependent increase in annexin A2 levels associated with medium from

219

Cellular response to low dose radiation: Role of phosphatidylinositol-3 kinase like kinases  

SciTech Connect

It is increasingly realized that human exposure either to an acute low dose or multiple chronic low doses of low LET radiation has the potential to cause different types of cancer. Therefore, the central theme of research for DOE and NASA is focused on understanding the molecular mechanisms and pathways responsible for the cellular response to low dose radiation which would not only improve the accuracy of estimating health risks but also help in the development of predictive assays for low dose radiation risks associated with tissue degeneration and cancer. The working hypothesis for this proposal is that the cellular mechanisms in terms of DNA damage signaling, repair and cell cycle checkpoint regulation are different for low and high doses of low LET radiation and that the mode of action of phosphatidylinositol-3 kinase like kinases (PIKK: ATM, ATR and DNA-PK) determines the dose dependent cellular responses. The hypothesis will be tested at two levels: (I) Evaluation of the role of ATM, ATR and DNA-PK in cellular response to low and high doses of low LET radiation in simple in vitro human cell systems and (II) Determination of radiation responses in complex cell microenvironments such as human EpiDerm tissue constructs. Cellular responses to low and high doses of low LET radiation will be assessed from the view points of DNA damage signaling, DNA double strand break repair and cell cycle checkpoint regulation by analyzing the activities (i.e. post-translational modifications and kinetics of protein-protein interactions) of the key target proteins for PI-3 kinase like kinases both at the intra-cellular and molecular levels. The proteins chosen for this proposal are placed under three categories: (I) sensors/initiators include ATM ser1981, ATR, 53BP1, gamma-H2AX, MDC1, MRE11, Rad50 and Nbs1; (II) signal transducers include Chk1, Chk2, FANCD2 and SMC1; and (III) effectors include p53, CDC25A and CDC25C. The primary goal of this proposal is to elucidate the differences in cellular defense mechanisms between low and high doses of low LET radiation and to define the radiation doses where the cellular DNA damage signaling and repair mechanisms tend to shift. This information is critically important to address and advance some of the low dose research program objectives of DOE. The results of this proposed study will lead to a better understanding of the mechanisms for the cellular responses to low and high doses of low LET radiation. Further, systematic analysis of the role of PIKK signaling pathways as a function of radiation dose in tissue microenvironment will provide useful mechanistic information for improving the accuracy of radiation risk assessment for low doses. Knowledge of radiation responses in tissue microenvironment is important for the accurate prediction of ionizing radiation risks associated with cancer and tissue degeneration in humans.

Balajee, A.S.; Meador, J.A.; Su, Y.

2011-03-24T23:59:59.000Z

220

Dose-Effect Relationship in Chemoradiotherapy for Locally Advanced Rectal Cancer: A Randomized Trial Comparing Two Radiation Doses  

SciTech Connect

Purpose: Locally advanced rectal cancer represents a major therapeutic challenge. Preoperative chemoradiation therapy is considered standard, but little is known about the dose-effect relationship. The present study represents a dose-escalation phase III trial comparing 2 doses of radiation. Methods and Materials: The inclusion criteria were resectable T3 and T4 tumors with a circumferential margin of {<=}5 mm on magnetic resonance imaging. The patients were randomized to receive 50.4 Gy in 28 fractions to the tumor and pelvic lymph nodes (arm A) or the same treatment supplemented with an endorectal boost given as high-dose-rate brachytherapy (10 Gy in 2 fractions; arm B). Concomitant chemotherapy, uftoral 300 mg/m{sup 2} and L-leucovorin 22.5 mg/d, was added to both arms on treatment days. The primary endpoint was complete pathologic remission. The secondary endpoints included tumor response and rate of complete resection (R0). Results: The study included 248 patients. No significant difference was found in toxicity or surgical complications between the 2 groups. Based on intention to treat, no significant difference was found in the complete pathologic remission rate between the 2 arms (18% and 18%). The rate of R0 resection was different in T3 tumors (90% and 99%; P=.03). The same applied to the rate of major response (tumor regression grade, 1+2), 29% and 44%, respectively (P=.04). Conclusions: This first randomized trial comparing 2 radiation doses indicated that the higher dose increased the rate of major response by 50% in T3 tumors. The endorectal boost is feasible, with no significant increase in toxicity or surgical complications.

Jakobsen, Anders, E-mail: anders.jakobsen@slb.regionsyddanmark.dk [Danish Colorectal Cancer Group South, Vejle Hospital, Vejle (Denmark) [Danish Colorectal Cancer Group South, Vejle Hospital, Vejle (Denmark); University of Southern Denmark, Odense (Denmark); Ploen, John [University of Southern Denmark, Odense (Denmark)] [University of Southern Denmark, Odense (Denmark); Vuong, Te [Department of Radiation Oncology, Jewish General Hospital, Montreal, Quebec (Canada)] [Department of Radiation Oncology, Jewish General Hospital, Montreal, Quebec (Canada); Appelt, Ane [Danish Colorectal Cancer Group South, Vejle Hospital, Vejle (Denmark) [Danish Colorectal Cancer Group South, Vejle Hospital, Vejle (Denmark); University of Southern Denmark, Odense (Denmark); Lindebjerg, Jan; Rafaelsen, Soren R. [Danish Colorectal Cancer Group South, Vejle Hospital, Vejle (Denmark)] [Danish Colorectal Cancer Group South, Vejle Hospital, Vejle (Denmark)

2012-11-15T23:59:59.000Z

Note: This page contains sample records for the topic "radiation dose equivalent" 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

Low Dose Radiation Research Program: Dual Regulation of JB6 Transformation  

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

Dual Regulation of JB6 Transformation by Low Dose Gamma Radiation. Dual Regulation of JB6 Transformation by Low Dose Gamma Radiation. Authors: Thomas J. Weber,1 Lye M. Markillie,1 William B. Chrisler,1 Xingye C. Lei,1 and Nancy H. Colburn2 Institutions: 1Molecular Biosciences, Pacific Northwest National Laboratory. 2Gene Regulation Section, Basic Research Laboratory, National Cancer Institute JB6 mouse epidermal cells have been instrumental in defining the molecular mechanisms associated with neoplastic transformation in response to known tumor promoters. JB6 cells exhibit a clonal growth response to oxygen free radicals suggesting this model may also be useful for radiation research. Treatment of JB6 cells with 2 and 20 cGy gamma radiation resulted in a weak, but dose-dependent increase in anchorage-independent growth observed

222

Low Dose Radiation Research Program: Mary Helen Barcellos-Hoff - 2003  

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

DOE Low Dose Radiation Program Workshop IV DOE Low Dose Radiation Program Workshop IV Abstract Title: TGF-β Protects Human Mammary Epithelial Cells from Radiation-Induced Centrosome Amplification Authors: Mary Helen Barcellos-Hoff, Bahram Parvin, Anna C. Erickson and Rishi Gupta Institutions: Department of Cell and Molecular Biology, Life Sciences Division, Ernest Orlando Lawrence, Berkeley National Laboratory, Berkeley, California In recent studies we have shown that ionizing radiation (IR), a known carcinogen of human and murine mammary gland, compromises human mammary epithelial cell (HMEC) polarity and multicellular organization in a manner characteristic of neoplastic progression through a heritable, non-mutational mechanism (1). Thus, when all cells are irradiated with a significant dose (2 Gy), the daughters of irradiated cells lose their

223

Earth-Moon-Mars Radiation Environment Model  

E-Print Network (OSTI)

successful at predicting SEP spectra and radiation dose estimates at different distances in the inner-dependent estimates of organ dose and dose equivalent rates for human crews in deep space from the 26 Oct 2003 solar orbit, Spaceweather, 8, 2010 · Dayeh, et al, Modeling proton intensity gradients and radiation dose

Pringle, James "Jamie"

224

Surgeon education decreases radiation dose in complex endovascular procedures and improves patient safety  

Science Journals Connector (OSTI)

Objective Complex endovascular procedures such as fenestrated endovascular aneurysm repair (FEVAR) are associated with higher radiation doses compared with other fluoroscopically guided interventions (FGIs). The purpose of this study was to determine whether surgeon education on radiation dose control can lead to lower reference air kerma (RAK) and peak skin dose (PSD) levels in high-dose procedures. Methods Radiation dose and operating factors were recorded for FGI performed in a hybrid room over a 16-month period. Cases exceeding 6 Gy RAK were investigated according to institutional policy. Information obtained from these investigations led to surgeon education focused on reducing patient dose. Points addressed included increasing table height, utilizing collimation and angulation, decreasing magnification modes, and maintaining minimal patient-to-detector distance. Procedural RAK doses and operating factors were compared 8 months pre- (group A) and 8 months post- (group B) educational intervention using analysis of variance with Tukey pairwise comparisons and t-tests. PSD distributions were calculated using custom software employing input data from fluoroscopic machine logs. Results Of 447 procedures performed, 300 \\{FGIs\\} had sufficient data to be included in the analysis (54% lower extremity, 11% thoracic endovascular aneurysm repair, 10% cerebral, 8% FEVAR, 7% endovascular aneurysm repair, 5% visceral, and 5% embolization). Twenty-one cases were investigated for exceeding 6 Gy RAK. FEVAR comprised 70% of the investigated cases and had a significantly higher median RAK dose compared with all other \\{FGIs\\} (Pradiation dose, and decreased the number of non-FEVAR cases that exceeded 6 Gy. It is essential thatvascular surgeons be educated in best operating practices to lower PSD; nonetheless, FEVAR remains a high-dose procedure.

Melissa L. Kirkwood; Gary M. Arbique; Jeffrey B. Guild; Carlos Timaran; Jayer Chung; Jon A. Anderson; R. James Valentine

2013-01-01T23:59:59.000Z

225

Low Dose Radiation Program: Links - Suggested Books and Literature for  

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

Suggested Books and Literature for Teachers about Radiation Suggested Books and Literature for Teachers about Radiation Popular Press News Articles Newspapers is an excellent portal or gateway to newspapers from all 50 states. To find a newspaper of interest, select a state and click Search. For a more specified search, fill in the Title of the newspaper and click Search. The newspapers available from that state are listed alphabetically. Hall, E., Radiation and Life Hall, E.J.Radiobiology for the Radiologist. 5th ed. Lippincott Williams & Wilkins, Philadelphia, PA. 2000 Nagai, T.Atomic Bomb Rescue and Relief Report. Nagasaki Association for Hibakushas' Medical Care (NASHIM), Nagasaki, Japan. 2000 Nagataki, S.Nagasaki Symposium on Chernobyl: Update and Future, Proceedings of "Chernobyl Update" 3 June 1994 at the 67th Annual Meeting of

226

Low Dose Radiation Research Program: Interaction between Tissue and  

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

between Tissue and Cellular Stress Responses: Effect of between Tissue and Cellular Stress Responses: Effect of TGF-ß Depletion on Radiation-Induced p53 Response M.H. Barcellos-Hoff, S.A. Ravani, R.L. Henshall, K.B. Ewan, R.L. Warters,* B. Parvin Lawrence Berkeley National Laboratory *University of Utah One of the most widely studied cellular responses to radiation is the activation of the transcription factor, p53, whose abundance and action dictates individual cellular fate decisions regarding proliferation, differentiation and death. A cell's response to damage needs to be rapid. Thus, it is not surprising that the activation of the p53 stress response primarily involves post-translational changes in the p53 protein. Whereas intracellular radiation-induced mediators of p53 stability have been the subject of intense study, little is known about the extracellular factors

227

Low Dose Radiation Research Program: Modeling Intercellular Interactions  

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

Modeling Intercellular Interactions During Radiation Carcinogenesis Modeling Intercellular Interactions During Radiation Carcinogenesis Authors: Rainer K Sachs,1 Michael Chan,2 Lynn Hlatky,3 Philip Hahnfeldt3 Institutions: 1Departments of Mathematics and Physics, University of California Berkeley California; 2School of Medicine, University of California at San Diego, La Jolla California; 3Department of Radiation Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston Massachusetts Abstract By modulating the microenvironment of malignant or pre-malignant epithelial cells, inhibitory or stimulatory signals from nearby cells, including those in stromal and vascular tissues, can play a key role in carcinogenesis; cancer is ultimately a disease of a whole-cell community, not just of a single cell, clone, or cell lineage. However, current commonly used

228

Low Dose Radiation Research Program: Interaction of Genome and Cellular  

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

of Genome and Cellular Micronenvioronment of Genome and Cellular Micronenvioronment Mina Bissell Life Sciences Division Lawrence Berkeley National Laboratory Why this Project While normal stoma can delay or prevent tumorigenesis, abnormal stromal components can promote tumor growth. Acquired or inherited mutations that alter stromal cell function can release the context-suppressed malignant cells. Literature spanning more than a century has shown that inflammation associated with tissue wounding can produce tunors. Radiation produces changes in reactive oxygen that are similar to inflammation and may represent a mechanism for radiation-induced damage. Project Goals To determine the underlying role of stromal alterations in controling genomic instability accompanying epithelial-mesenchyumal transformation.

229

Activation of mitogen-activated protein kinase pathway by extremely low-dose ionizing radiation  

Science Journals Connector (OSTI)

X-ray irradiation at very low doses, between 2 and 5 cGy, stimulated activity of a member of the mitogen-activated protein (MAP) kinase, the extracellular signal-regulated kinase (ERK) 1/2 in normal human diploid cells. Higher doses of irradiation at more than 1 Gy induced phosphorylation of ERK1/2 and accumulated p53 protein. Phosphorylation of ERK1/2 decreased with doses down to 50 cGy, however, doses of between 2 and 5 cGy phosphorylated ERK1/2 as efficiently as higher doses of X-rays, while the p53 protein level was no longer changed by doses below 50 cGy. Ataxia telangiectasia-mutated (ATM)-dependent phosphorylation of p53 protein at Ser15 and histone H2AX at Ser139 was only observed at higher doses of more than 10 cGy of X-rays. We found that the MEK1 inhibitor, PD98059, and the specific epidermal growth factor receptor tyrosine kinase inhibitor, AG1478, decreased phosphorylation of the ERK1/2 proteins induced by 2 cGy or 6 Gy of X-rays. These results indicate that a limited range of low-dose ionizing radiation differentially activates ERK1/2 kinases via activation of the epidermal growth factor receptor and MAP kinaseERK kinase, which mediates various effects of cells receiving very low doses of ionizing radiation.

Keiji Suzuki; Seiji Kodama; Masami Watanabe

2003-01-01T23:59:59.000Z

230

A method for estimating occupational radiation dose to individuals, using weekly dosimetry data  

SciTech Connect

Statistical analyses of data from epidemiologic studies of workers exposed to radiation have been based on recorded annual radiation doses. It is usually assumed that the annual dose values are known exactly, although it is generally recognized that the data contain uncertainty due to measurement error and bias. We propose the use of a probability distribution to describe an individual`s dose during a specific period of time. Statistical methods for estimating this dose distribution are developed. The methods take into account the ``measurement error`` that is produced by the dosimetry system, and the bias that was introduced by policies that lead to right censoring of small doses as zero. The method is applied to a sample of dose histories obtained from hard copy dosimetry records at Oak Ridge National Laboratory (ORNL). The result of this evaluation raises serious questions about the validity of the historical personnel dosimetry data that is currently being used in low-dose studies of nuclear industry workers. In particular, it appears that there was a systematic underestimation of doses for ORNL workers. This could result in biased estimates of dose-response coefficients and their standard errors.

Mitchell, T.J.; Ostrouchov, G.; Frome, E.L.; Kerr, G.D.

1993-12-01T23:59:59.000Z

231

Estimates of Radiation Dose from Strontium-90 Due to Fallout  

Science Journals Connector (OSTI)

...2412"` d., 74" h. 2" fiberglas insulation. 1 50() watts, 11 5, 208, or 230...gratings, electro-luminescence, thermal radiation backgrounds, infrared polarizers...chart. Write for complete data and specifications. SMALL ANIMAL BALANCE Model 4203B-TC-SA...

MERRIL EISENBUD

1959-09-18T23:59:59.000Z

232

Low-Dose Ionizing Radiation Alters the Epigenome of the Avy Mouse  

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

Ionizing Radiation Alters the Epigenome of the A Ionizing Radiation Alters the Epigenome of the A vy Mouse Autumn Bernal 1,2,3 , Dale Huang 1 , Yue Li 4 , Dana Dolinoy 5 , and Randy Jirtle 1 Department of Radiation Oncology 1 , University Program in Genetics and Genomic 2 , Integrated Toxicology & Environmental Health Program 3 , Department of Community and Family Medicine 4 , Duke University Medical Center, Durham, NC, USA, Department of Environmental and Health Sciences, University of Michigan, Ann Arbor, MI, USA 4 Background: Humans have evolved and thrived amidst constant low-dose (0-10 cGy) background radiation exposure from natural sources. Currently, however, the frequency of exposures to low doses of radiation is increasing due to man-made sources such as diagnostic imaging and nuclear power. This increased exposure has led to concerns amongst the general public and the government about the

233

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

234

RADIATION CARCINOGENESIS IN MAN: INFLUENCE OF DOSE-RESPONSE MODELS AND RISK PROJECTION MODELS IN THE ESTIMATION OF RISK COEFFICIENTS FOLLOWING EXPOSURE TO LOW-LEVEL RADIATION  

E-Print Network (OSTI)

RADIATION CARCINOGENESIS IN MAN: INFLUENCE OF DOSE-RESPONSE MODELS AND RISK PROJECTION MODELS IN THE ESTIMATIONRADIATION CARCINOGENESIS IN HAN: INFLUENCE OF DOSE-RESPONSE MODELS AND RISK PROJECTION MODELS IN THE ESTIMATION

Fabrikant, J.I.

2010-01-01T23:59:59.000Z

235

Low Dose Radiation Research Program: Molecular Mechanisms of  

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

Molecular Mechanisms of Radiation-Induced Genomic Instability in Human Molecular Mechanisms of Radiation-Induced Genomic Instability in Human Cells Howard L. Liber Department of Environmental and Radiological Health Sciences Colorado State University Why This Project This research will be to investigate the condition known as genomic instability. This can be defined as a state in which genetic alterations, including chromosome aberrations and gene mutations, occur at rates that are much higher than normal. In fact, genomic instability is what allows a normal cell to accumulate the multiple genetic alterations that are required to convert it into a cancer cell. The chromosomes of human cells have structures at their ends called telomeres. Telomeres normally function to prevent chromosomes from fusing together end-to-end. An important

236

Low Dose Radiation Research Program: The Progeny of Irradiated Mammary  

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

Progeny of Irradiated Mammary Epithelial Cells Exhibit a Phenotype Progeny of Irradiated Mammary Epithelial Cells Exhibit a Phenotype Characteristic of Malignancy Mary H. Barcellos-Hoff, R.L. Henshall-Powell, M.J. Bissell, and B. Parvin Lawrence Berkeley National Laboratory, Life Sciences Division We have proposed that the ability of radiation to induce altered microenvironments affects the frequency and features of neoplastic progression. Thus, we have sought to characterize the irradiated microenvironment and determine how these events contribute to mammary carcinogenesis. By using imaging bioinformatics to analyze mouse and human models of breast cancer we have now examined cell adhesion molecules (CAMs) critical for tissue-specific organization and function. We found that 1) radiation-induced microenvironments can contribute to neoplastic potential

237

Mechanisms underlying cellular responses of cells from haemopoietic tissue to low dose/low LET radiation  

SciTech Connect

To accurately define the risks associated with human exposure to relevant environmental doses of low LET ionizing radiation, it is necessary to completely understand the biological effects at very low doses (i.e., less than 0.1 Gy), including the lowest possible dose, that of a single electron track traversal. At such low doses, a range of studies have shown responses in biological systems which are not related to the direct interaction of radiation tracks with DNA. The role of these non-targeted responses in critical tissues is poorly understood and little is known regarding the underlying mechanisms. Although critical for dosimetry and risk assessment, the role of individual genetic susceptibility in radiation risk is not satisfactorily defined at present. The aim of the proposed grant is to critically evaluate radiation-induced genomic instability and bystander responses in key stem cell populations from haemopoietic tissue. Using stem cells from two mouse strains (CBA/H and C57BL/6J) known to differ in their susceptibility to radiation effects, we plan to carefully dissect the role of genetic predisposition on two non-targeted radiation responses in these models; the bystander effect and genomic instability, which we believe are closely related. We will specifically focus on the effects of low doses of low LET radiation, down to doses approaching a single electron traversal. Using conventional X-ray and ?-ray sources, novel dish separation and targeted irradiation approaches, we will be able to assess the role of genetic variation under various bystander conditions at doses down to a few electron tracks. Irradiations will be carried out using facilities in routine operation for bystander targeted studies. Mechanistic studies of instability and the bystander response in different cell lineages will focus initially on the role of cytokines which have been shown to be involved in bystander signaling and the initiation of instability. These studies also aim to uncover protein mediators of the bystander responses using advanced proteomic screening of factors released from irradiated, bystander and unstable cells. Integral to these studies will be an assessment of the role of genetic susceptibility in these responses, using CBA/H and C57BL/6J mice. The relevance of in vivo interactions between stem cells and the stem cell niche will be explored in the future by re-implantation techniques of previously irradiated cells. The above studies will provide fundamental mechanistic information relating genetic predisposition to important low dose phenomena, and will aid in the development of Department of Energy policy, as well as radiation risk policy for the public and the workplace. We believe the proposed studies accurately reflect the goals of the DOE low dose program.

Munira A Kadhim

2010-03-05T23:59:59.000Z

238

Extremely Low-Dose Ionizing Radiation Causes Activation of Mitogen-activated Protein Kinase Pathway and Enhances Proliferation of Normal Human Diploid Cells  

Science Journals Connector (OSTI)

...stimulative effect of low-dose irradiation. These results indicate that a limited range of low-dose ionizing radiation differentially activates...indicate that a limited range of low-dose ionizing radiation differentially activates...

Keiji Suzuki; Seiji Kodama; and Masami Watanabe

2001-07-15T23:59:59.000Z

239

The Mechanism of Low Dose Radiation Risk Associated with Diagnostic X-rays,  

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

Mechanism of Low Dose Radiation Risk Associated with Diagnostic X-rays, Mechanism of Low Dose Radiation Risk Associated with Diagnostic X-rays, PET, and Gamma-rays Douglas Boreham McMaster University Abstract The goal of this project was to investigate low dose ionizing radiation effects associated with exposure to diagnostic computed tomography (CT) or positron emission tomography (PET) scans. Biological effects were evaluated in wild type and Trp53+/- heterozygous females, following in vivo exposure to diagnostic CT (75kVp, 200µ) or PET (18F-FDG) scans. The short term biological effects following CT or PET scans were evaluated in order to understand biological modification of mechanisms, such as DNA repair processes and apoptosis, that might alter long term cancer risk. Corresponding life-time cancer risk studies are in progress. Short-term

240

Low Dose Radiation Research Program: The Role of the Number and Spacing of  

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

Program Workshop I Program Workshop I November 10-12, 1999, Washington, D.C. The Role of the Number and Spacing of Electron Tracks on the Consequences of Low Dose Irradiation Leslie A. Braby and J. R. Ford Nuclear Engineering, Texas A&M University, 129 Zachry, College Station, Texas. Summary: Biological mechanisms, which may influence the health risks resulting from very low dose radiation exposures, will be investigated using a collimated beam of electrons to simulate the irradiation patterns occurring with low dose exposures. Abstract: Ionizing radiation produces a variety of free radicals and chemical products that react to produce the same types of oxidative damage in a mammalian cell as produced by the normal metabolic activity of the cell. However, the damage produced by radiation is distributed differently

Note: This page contains sample records for the topic "radiation dose equivalent" 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.


241

Proteomic and Biochemical Studies of Human Mesenchymal Stem Cells in Response to Low Dose Ionizing Radiation  

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

Proteomic and Biochemical Studies of Human Mesenchymal Stem Cells Proteomic and Biochemical Studies of Human Mesenchymal Stem Cells in Response to Low Dose Ionizing Radiation Deok-Jin Jang 1 , Mingquan Guo 1 , Julia S.F.Chu 2 , Kyle T. Kurpinski 2 , Bjorn Rydberg 1 , Song Li 2 , and Daojing Wang 1 1. Life Sciences Division, Lawrence Berkeley National Lab, Berkeley, CA 94720 2. Department of Bioengineering, University of California, Berkeley, CA 94720 We will present data obtained during the first year of our DOE/NASA Low Dose Radiation Research program. We utilized a comprehensive approach including transcriptomics, proteomics, phosphoproteomics, and biochemistry to characterize human mesenchymal stem cells (MSCs) in response to low dose ionizing radiation. We first determined the cell survival, proliferation, and osteogenic differentiation of

242

Investigation of non-targeted effects of low dose ionizing radiation on the mammary gland  

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

non-targeted effects of low dose ionizing radiation on the mammary gland non-targeted effects of low dose ionizing radiation on the mammary gland utilizing three-dimensional culture models of mammary cells derived from mouse strains that differ in susceptibility to tumorigenesis Joni D. Mott, Antoine M. Snijders, Alvin Lo, Dinah Levy-Groesser, Bahram Parvin, Andrew J. Wyrobek, Jian-Hua Mao, and Mina J. Bissell Life Sciences Division, Lawrence Berkeley National Laboratory, Berkeley CA 94720 Goal: Within the Lawrence Berkeley National Laboratory's SFA, Project 2, our studies focus on utilizing three dimensional (3D) cell culture models as surrogates for in vivo studies to determine how low doses of ionizing radiation influence mammary gland tissue architecture and how this may relate both to tumor progression and/or adaptive response.

243

Hypothesis regarding a membrane-associated mechanism of biological action due to low-dose ionizing radiation  

Science Journals Connector (OSTI)

A novel theory is proposed regarding the action of ionizing radiation in the range of very low doses. The basic premise of the theory presented is that the low-dose effect cannot be explained by direct damage ......

Lazar Kh. Eidus

2000-09-01T23:59:59.000Z

244

Using the Microsoft Kinect for Patient Size Estimation and Radiation Dose Normalization: Proof of Concept and Initial Validation  

Science Journals Connector (OSTI)

Monitoring patients' imaging-related radiation is currently a hot topic, but there ... are many obstacles to accurate, patient-specific dose estimation. While some, such as easier access to dose data and paramete...

Tessa S. Cook; Gregory Couch; Timothy J. Couch; Woojin Kim

2013-08-01T23:59:59.000Z

245

Calculation of radiation therapy dose using all particle Monte Carlo transport  

DOE Patents (OSTI)

The actual radiation dose absorbed in the body is calculated using three-dimensional Monte Carlo transport. Neutrons, protons, deuterons, tritons, helium-3, alpha particles, photons, electrons, and positrons are transported in a completely coupled manner, using this Monte Carlo All-Particle Method (MCAPM). The major elements of the invention include: computer hardware, user description of the patient, description of the radiation source, physical databases, Monte Carlo transport, and output of dose distributions. This facilitated the estimation of dose distributions on a Cartesian grid for neutrons, photons, electrons, positrons, and heavy charged-particles incident on any biological target, with resolutions ranging from microns to centimeters. Calculations can be extended to estimate dose distributions on general-geometry (non-Cartesian) grids for biological and/or non-biological media.

Chandler, William P. (Tracy, CA); Hartmann-Siantar, Christine L. (San Ramon, CA); Rathkopf, James A. (Livermore, CA)

1999-01-01T23:59:59.000Z

246

Estimation of organs doses and radiation-induced secondary cancer risk from scattered photons for conventional radiation therapy of nasopharynx: a Monte Carlo study  

Science Journals Connector (OSTI)

We used Monte Carlo modeling to calculate the organs doses due to out-of field photons during radiation therapy of the nasopharynx.

Asghar Mesbahi; Farshad Seyednejad; Amir Gasemi-Jangjoo

2010-06-01T23:59:59.000Z

247

Answers to questions about updated estimates of occupational radiation doses at Three Mile Island, Unit 2  

SciTech Connect

The purpose of this question and answer report is to provide a clear, easy-to-understand explanation of revised radiation dose estimates which workers are likely to receive over the course of the cleanup at Three Mile Island, Unit 2, and of the possible health consequences to workers of these new estimates. We will focus primarily on occupational dose, although pertinent questions about public health and safety will also be answered.

Not Available

1983-12-01T23:59:59.000Z

248

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

249

Low Dose Radiation Research Program: Funded Project Descriptions  

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

Funded Project Descriptions Funded Project Descriptions Non-Invasive Early Detection and Molecular Analysis of Low X-Ray Dose Effects in the Lens Jointly funded by NASA and DOE Principal Investigator: Lee Goldstein, M.D., Ph.D., Associate Professor in Psychiatry, Neurology, Ophthalmology, Pathology and Laboratory Medicine, & Biomedical Engineering, Boston University’s School Medicine, College of Engineering, and Photonics Center. Boston, Ma. The project includes a new DOE FWP (~$400 K over 3 years) to Lawrence Berkeley National Laboratory with Eleanor Blakely as Project Leader. The work includes a subcontract to support the collaboration of Polly Chang of SRI, International, Menlo Park, CA. and is scheduled to begin as early as August 2009. This proposal was submitted in response to the joint DOE/NASA

250

An integrated genetics approach to systemic low-dose radiation responses  

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

integrated genetics approach to systemic low-dose radiation responses integrated genetics approach to systemic low-dose radiation responses G. Huang 1 , Y. Huang 1 , D.H. Nguyen 1 , K. Bjornstad 1 , C. Rosen 1 , P. Chang 2 , R. DelRosario 3 , Do Yup Lee 1 , B. Bowen 1 , W. Reindl 1 , J. Mott 1 , A. Balmain 3 , M.H. Barcellos-Hoff 4 , Joe W Gray 1,5 , Mina Bissell 1 , Gary Karpen 1 , T. Northen 1 , E. A. Blakely 1 , J. H. Mao 1 1 Life Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 2 SRI International, Menlo Park, CA

251

Low Dose Radiation Research Program: Role of TNF-α as a Potential  

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

Role of TNF-α as a Potential Signaling Mediator of Role of TNF-α as a Potential Signaling Mediator of Radiation-Induced Bystander Effect in Human Vascular Cells. Authors: Mohan Natarajan, Sumathy Mohan, Catherine Gibbons, Yan Bo and Munira A. Kadhim Institutions: Departments of Radiation Oncology and Pathology, University of Texas Health Science Center, San Antonio, Texas; Environmental Toxicology Graduate Program, University of California, Riverside; Radiation and Genomic Stability Unit, Medical research Council, Oxford, United Kingdom Identifying reliable and sensitive signaling pathways that are implicated in adverse health effects after exposure to low doses of ionizing radiation would allow us to understand the scientific basis of low dose-induced signaling pathways and their downstream phenotypic expression. This

252

Low Dose Radiation Research Program: Wide Expression of LLIR and the  

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

Wide Expression of LLIR and the Biological Consequences Wide Expression of LLIR and the Biological Consequences David J. Chen Lawrence Berkeley National Laboratory Why This Project It is known that changes in gene expression alter biological effects. It is necessary to identify the specific genes that demonstrate altered expression after exposure to low doses of ionizing radiation and to determine pathways involved in DNA damage recognition, signaling, and repair that are associated with radiation-induced adaptive and bystander effects. Project Goals Identification of genes whose transcription is regulated in response to low levels of ionizing radiation Identification of the genes and communication pathways that control these responses to low dose radiation Identification of the cellular and molecular targets that influence

253

Low Dose Radiation Research Program: Using a Low LET Electron Microbeam to  

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

Using a Low LET Electron Microbeam to Investigate Non-Targeted Using a Low LET Electron Microbeam to Investigate Non-Targeted Effects of Low Dose Radiation Authors: William F. Morgan1 and Marianne B. Sowa2 Institutions: 1Radiation Oncology Research Laboratory, University of Maryland, Baltimore, Maryland; 2Chemical Structure and Dynamics, Pacific Northwest National Laboratory, Richland Washington We have recently installed a low-linear energy transfer (LET) electron microbeam that generates energetic electrons to mimic radiation damage from gamma- and x-ray sources. It has been designed such that high-energy electrons deposit energy in a pre-selected subset of cells, leaving neighboring cells unirradiated (Figure 1). In this way it is possible to examine non-targeted effects associated with low dose radiation exposure,

254

Low Dose Radiation Research Program: Research Highlights - Real-time  

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

Real-time imaging of repair processes possible with Nickel-63 Real-time imaging of repair processes possible with Nickel-63 microirradiator Microscope Microscope stage-mounted microirradiation system. (A) Overall system shown mounted on a micromanipulator housed within a heated, humidified, environmental chamber of a microscope. (B) Close-up showing attachment of device to the micromanipulator. (C) Detail showing the bend in the enclosing capillary, which allows positioning of the active surface directly above the target cell. (D) Microirradiator tip in dissecting microscope. (E) Close-up view through microscope optics (scale bar, 10 microns.) Background: Scientists know that mammalian cells begin a nucleoplasmic repair process within seconds after being exposed to ionizing radiation. Real-time imaging of this process could further understanding of the

255

Low Dose Radiation Research Program: Quantitative Analysis of Connexin  

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

Quantitative Analysis of Connexin Expression in Cultured Colonies Quantitative Analysis of Connexin Expression in Cultured Colonies Authors: B. Parvin, Q. Yang, R. L. Henshall-Powell and M.H. Barcellos Hoff We are studying the effects of ionizing radiation on the signaling between human mammary epithelial cells and the extracellular microenvironment. To do so we use an assay based on the ability of the cells to organize into three-dimensional acini when embedded into an extracellular matrix. Although tumorigenic and non-tumorigenic mammary epithelial cells are nearly indistinguishable when cultured as monolayers, their biological character readily diverge when tissue-specific morphogenesis is analyzed. Non-malignant human mammary epithelial cells (HMEC) cultured within a reconstituted basement membrane organize into acinar-like structures with

256

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

257

85Kr management trade-offs: a perspective to total radiation dose commitment  

SciTech Connect

Radiological consequences arising from the trade-offs for /sup 85/Kr waste management from possible nuclear fuel resource recovery activities have been investigated. The reference management technique is to release all the waste gas to the atmosphere where it is diluted and dispersed. A potential alternative is to collect, concentrate, package and submit the gas to long-term storage. This study compares the radiation dose commitment to the public and to the occupationally exposed work force from these alternatives. The results indicate that it makes little difference to the magnitude of the world population dose whether /sup 85/Kr is captured and stored or chronically released to the environment. Further, comparisons of radiation exposures (for the purpose of estimating health effects) at very low dose rates to very large populations with exposures to a small number of occupationally exposed workers who each receive much higher dose rates may be misleading. Finally, cost studies (EPA 1976 and DOE 1979a) show that inordinate amounts of money will be required to lower this already extremely small 80-year cumulative world population dose of 0.05 mrem/person (<0.001% of natural background radiation for the same time period).

Mellinger, P.J.; Hoenes, G.R.; Brackenbush, L.W.; Greenborg, J.

1980-01-01T23:59:59.000Z

258

CHIPLESS PASSIVE SENSOR FOR WIRELESS MONITORING OF HIGH RADIATION DOSES IN NUCLEAR INFRASTRUCTURES  

E-Print Network (OSTI)

CHIPLESS PASSIVE SENSOR FOR WIRELESS MONITORING OF HIGH RADIATION DOSES IN NUCLEAR INFRASTRUCTURES for Nuclear Research, Otwock, Poland 4 Wroclaw University of Technology, Wroclaw, Poland 5 TRAD, BP 47471, Labège, France ppons@laas.fr ABSTRACT The dosimetry is one of the crucial techniques that are needed

Paris-Sud XI, Université de

259

Applied Radiation and Isotopes 64 (2006) 6062 Weak energy dependence of EBT gafchromic film dose  

E-Print Network (OSTI)

is almost free of all these drawbacks. Its response is relatively energy-independent, and its sensitivityApplied Radiation and Isotopes 64 (2006) 60­62 Weak energy dependence of EBT gafchromic film dose of Physics and Materials Science, City University of Hong Kong, Kowloon Tong, Hong Kong b Department

Yu, K.N.

260

Assessment of the Technologies for Molecular Biodosimetry for Human Low-Dose Radiation Exposure Symposium  

SciTech Connect

Exposure to ionizing radiation produces few immediate outwardly-visible clinical signs, yet, depending on dose, can severely damage vital physiological functions within days to weeks and produce long-lasting health consequences among survivors. In the event of a radiological accident, the rapid evaluation of the individual absorbed dose is paramount to discriminate the worried but unharmed from those individuals who must receive medical attention. Physical, clinical and biological dosimetry are usually combined for the best dose assessment. However, because of the practical limits of physical and clinical dosimetry, many attempts have been made to develop a dosimetry system based on changes in biological parameters, including techniques for hematology, biochemistry, immunology, cytogenetics, etc. Lymphocyte counts and chromosome aberrations analyses are among the methods that have been routinely used for estimating radiation dose. However, these assays require several days to a week to be completed and therefore cannot be used to obtain a fast estimate of the dose during the first few days after exposure when the information would be most critical for identifying victims of radiation accidents who could benefit the most by medical intervention. The steadily increasing sophistication in our understanding of the early biochemical responses of irradiated cells and tissues provides the opportunity for developing mechanism-based biosignatures of exposure. Compelling breakthroughs have been made in the technologies for genome-scale analysis of cellular transcriptional and proteomic profiles. There have also been major strides in the mechanistic understanding of the early events in DNA damage and radiation damage products, as well as in the cellular pathways that lead to radiation injury. New research with genomic- and proteomic-wide tools is showing that within minutes to hours after exposure to ionizing radiation protein machines are modified and activated, and large-scale changes occur in the gene expression profile involving a broad variety of cell-process pathways after a wide range of both low (<10 cGy) and high dose (>10 cGy) exposures. Evaluation of these potential gene and protein biomarkers for early and late diagnostic information will be critical for determining the efficacy of the signatures to both low and high dose IR exposures. Also needed are approaches that enable rapid handling and processing for mass-casualty and population triage scenarios. Development of in vivo model system will be crucial for validating both the biological and the instrumentation for biodosimetry. Such studies will also help further understanding of the molecular mechanisms of the biological effects of radiation and the differences of responses due to individual genetic variation.

Matthew A. Coleman Ph.D.; Narayani Ramakrishnan, Ph.D.; Sally A. Amundson; James D. Tucker, Ph.D.; Stephen D. Dertinger, Ph.D.; Natalia I. Ossetrova, Ph.D.; Tao Chen

2009-11-16T23:59:59.000Z

Note: This page contains sample records for the topic "radiation dose equivalent" 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.


261

Molecular Mechanisms of Low Dose Radiation Mediated Hormesis in C. elegans  

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

Mechanisms of Low Dose Radiation Mediated Hormesis in C. Mechanisms of Low Dose Radiation Mediated Hormesis in C. elegans Anders Olsen, Maithili C. Vantipalli, Arnold Kahn, Judith Campisi and Gordon J. Lithgow. Buck Institute for Age Research, 8001 Redwood Boulevard, Novato CA 94945 Brief exposure to a mild stress causes induction of stress gene expression leading to enhanced stress responses, improved maintenance and repair and in some cases lifespan increase. This phenomenon is termed hormesis and has been observed in several species. For example, we previously demonstrated that short periods of mild heat stress in early life increase both mean and maximum lifespan of the soil nematode C. elegans. Similar hormetic responses have been described for many other stressors. Here we present data showing that treatment of the nematode with low-doses of ionizing

262

Low Dose Radiation Research Program: Genetic Control of Repair and Adaptive  

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

Repair and Adaptive Responses to Low-level DNA Damage Repair and Adaptive Responses to Low-level DNA Damage James E. Haber Brandeis University Why This Project In order to fully understand mechanisms resulting in effects of low dose, whole system rather than cells must be examined. Although not identical to mammalian systems, simple systems usually have many similarities and give direction for further study of more complex systems. We use the budding yeast, Saccharomyces cerevisiae, as a model system because it is easy to manipulate and its genome is simple and well characterized. Project Goals Examine mechanisms and effects of low dose radiation response for: Genetic recombination mechanisms that lead to genomic instability Genetic factors that affect individual susceptibility to low-dose radiation The adaptive response

263

Low Dose Radiation Research Program: Mechanisms of Tissue Response to Low  

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

Tissue Response to Low Dose Radiation Tissue Response to Low Dose Radiation Mary Helen Barcellos-Hoff Lawrence Berkeley National Laboratory Why This Project? In the past, the effects of ionizing radiation on humans has been attributed in great part to its ability to damage DNA, which transmits information from cell to cell, and generation to generation. Damaged DNA can lead to cell death or perpetuate the damage to daughter cells and to future generations. In addition to the information contained with the genome (i.e., DNA sequence), information directing cell behavior and tissue function is also stored outside the DNA. The success in cloning sheep from the DNA contained in the nucleus of an adult cell shows how important signals from the outside are in defining how the genome is expressed. This

264

PARP-1, PARP-2, and the cellular response to low doses of ionizing radiation  

Science Journals Connector (OSTI)

Purpose Poly(ADP-ribose) polymerase-1 (PARP-1) is rapidly and directly activated by single-strand breaks and is required for efficient base excision repair. These properties indicate that inhibition of PARP-1 might enhance the cellular response to low doses of radiation. We tested the effect of chemical inhibition of PARP-1 on low-dose clonogenic survival in a number of cell lines and the low-dose radiation response of a PARP-1 knockout murine cell line. Methods and materials Clonogenic cell survival of V79-379A and CHO-K1 hamster fibroblasts, T98G and U373-MG human glioma cells, and 3T3 mouse embryo fibroblast PARP-1 knockout cells was measured using a precise flow cytometry-based plating assay. Chemical inhibitors of PARP enzymes were tested for their effect on clonogenic survival after a range of ionizing radiation doses. Results Chemical inhibition of PARP activity induced marked radiosensitization of V79, CHO, and exponentially growing T98G cells in the 0.050.3-Gy range. This effect was not seen in U373 cells or in confluent T98G populations. Low-dose radiosensitization was not apparent in PARP-1 knockout cells. Conclusion Low-dose radiosensitization of actively dividing tumor cells by PARP-1 inhibitors suggests that they may have a role in enhancing the efficacy of ultrafractionated or low-dose-rate radiotherapy regimens. We hypothesize that PARP-2 compensates for the absence of PARP-1 in the knockout cell line.

Anthony Chalmers; Peter Johnston; Mick Woodcock; Michael Joiner; Brian Marples

2004-01-01T23:59:59.000Z

265

Calculation of gamma radiation dose rate and radon concentration due to granites used as building materials in Iran  

Science Journals Connector (OSTI)

......G. Magusa, North Cyprus, via Mersin 10, Turkey Natural radioactivity concentrations...equivalent from all natural sources of radiation...health(4). Radon gas is a radionuclide present...to determining the natural radioactivity concentration......

A. Abbasi

2013-07-01T23:59:59.000Z

266

Radiation-Induced Rib Fractures After Hypofractionated Stereotactic Body Radiation Therapy: Risk Factors and Dose-Volume Relationship  

SciTech Connect

Purpose: The purpose of this study was to clarify the incidence, the clinical risk factors, and the dose-volume relationship of radiation-induced rib fracture (RIRF) after hypofractionated stereotactic body radiation therapy (SBRT). Methods and Materials: One hundred sixteen patients treated with SBRT for primary or metastatic lung cancer at our institution, with at least 6 months of follow-up and no previous overlapping radiation exposure, were included in this study. To determine the clinical risk factors associated with RIRF, correlations between the incidence of RIRF and the variables, including age, sex, diagnosis, gross tumor volume diameter, rib-tumor distance, and use of steroid administration, were analyzed. Dose-volume histogram analysis was also conducted. Regarding the maximum dose, V10, V20, V30, and V40 of the rib, and the incidences of RIRF were compared between the two groups divided by the cutoff value determined by the receiver operating characteristic curves. Results: One hundred sixteen patients and 374 ribs met the inclusion criteria. Among the 116 patients, 28 patients (46 ribs) experienced RIRF. The estimated incidence of rib fracture was 37.7% at 3 years. Limited distance from the rib to the tumor (<2.0 cm) was the only significant risk factor for RIRF (p = 0.0001). Among the dosimetric parameters used for receiver operating characteristic analysis, the maximum dose showed the highest area under the curve. The 3-year estimated risk of RIRF and the determined cutoff value were 45.8% vs. 1.4% (maximum dose, {>=}42.4 Gy or less), 51.6% vs. 2.0% (V40, {>=}0.29 cm{sup 3} or less), 45.8% vs. 2.2% (V30, {>=}1.35 cm{sup 3} or less), 42.0% vs. 8.5% (V20, {>=}3.62 cm{sup 3} or less), or 25.9% vs. 10.5% (V10, {>=}5.03 cm{sup 3} or less). Conclusions: The incidence of RIRF after hypofractionated SBRT is relatively high. The maximum dose and high-dose volume are strongly correlated with RIRF.

Asai, Kaori [Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, Fukuoka (Japan)] [Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, Fukuoka (Japan); Shioyama, Yoshiyuki, E-mail: shioyama@radiol.med.kyushu-u.ac.jp [Department of Heavy Particle Therapy and Radiation Oncology, Graduate School of Medical Sciences, Kyushu University, Fukuoka (Japan)] [Department of Heavy Particle Therapy and Radiation Oncology, Graduate School of Medical Sciences, Kyushu University, Fukuoka (Japan); Nakamura, Katsumasa; Sasaki, Tomonari; Ohga, Saiji; Nonoshita, Takeshi [Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, Fukuoka (Japan)] [Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, Fukuoka (Japan); Yoshitake, Tadamasa [Department of Heavy Particle Therapy and Radiation Oncology, Graduate School of Medical Sciences, Kyushu University, Fukuoka (Japan)] [Department of Heavy Particle Therapy and Radiation Oncology, Graduate School of Medical Sciences, Kyushu University, Fukuoka (Japan); Ohnishi, Kayoko [Department of Radiology, National Center for Global Health and Medicine, Tokyo (Japan)] [Department of Radiology, National Center for Global Health and Medicine, Tokyo (Japan); Terashima, Kotaro; Matsumoto, Keiji [Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, Fukuoka (Japan)] [Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, Fukuoka (Japan); Hirata, Hideki [Department of Health Sciences, Graduate School of Medical Sciences, Kyushu University, Fukuoka (Japan)] [Department of Health Sciences, Graduate School of Medical Sciences, Kyushu University, Fukuoka (Japan); Honda, Hiroshi [Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, Fukuoka (Japan)] [Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, Fukuoka (Japan)

2012-11-01T23:59:59.000Z

267

Estimation of children's radiation dose from cardiac catheterisations, performed for the  

Science Journals Connector (OSTI)

Entrance surface radiation doses were measured with thermoluminescent dosimeters for 98 children who were referred to a cardiology department for the diagnosis or the treatment of a congenital heart disease. Additionally, all the radiographic parameters were recorded and Monte Carlo simulations were performed for the estimation of entrance surface dose to effective dose conversion factors, in order to further calculate the effective dose for each child. For diagnostic catheterisations the values ranged from 0.16 to 14.44mSv, with average 3.71mSv, and for therapeutic catheterisations the values ranged from 0.38 to 25.01mSv, with average value 5mSv. Effective doses were estimated for diagnostic procedures and interventional procedures performed for the treatment of five different heart diseases: (a)atrial septal defect (ASD), (b)ventricular septal defect (VSD), (c)patent ductus arteriosus (PDA), (d)aorta coarctation and (e)pulmonary stenosis. The high levels of radiation exposure are, however, balanced with the advantages of cardiac catheterisations such as the avoidance of surgical closure and the necessity of shorter or even nohospitalisation.

E N Yakoumakis; G I Gialousis; Despina Papadopoulou; Triantafillia Makri; Zografia Pappouli; Nikolaos Yakoumakis; Panayotis Papagiannis; Evangelos Georgiou

2009-01-01T23:59:59.000Z

268

Uptake, depuration, and radiation dose estimation in zebrafish exposed to radionuclides via aqueous or dietary routes  

Science Journals Connector (OSTI)

Understanding uptake and depuration of radionuclides in organisms is necessary to relate exposure to radiation dose and ultimately to biological effects. We investigated uptake and depuration of a mixture of radionuclides to link bioaccumulation with radiation dose in zebrafish, Danio rerio. Adult zebrafish were exposed to radionuclides (54Mn, 60Co, 65Zn, 75Se, 109Cd, 110mAg, 134Cs and 241Am) at tracer levels (dose rates were modelled from activity concentrations in whole body and exposure medium (water or diet). After 14-day aqueous exposure, radionuclides were detected in decreasing activity concentrations: 75Se>65Zn>109Cd>110mAg>54Mn>60Co>241Am>134Cs (range: 1758Bqg1). After dietary exposure the order of radionuclide activity concentration in tissues (Bqg?1) was: 65Zn>60Co>75Se>109Cd>110mAg>241Am>54Mn>134Cs (range: 911Bqg?1). Aqueous exposure resulted in higher whole body activity concentrations for all radionuclides except 60Co. Route of exposure did not appear to influence activity concentrations in gonads, except for 54Mn, 65Zn, and 75Se, which had higher activity concentrations in gonads following aqueous exposure. Highest gonad activity concentrations (Bqg?1) were for 75Se (211), 109Cd (142), and 65Zn (117), and highest dose rates (?Gyh?1) were from 241Am (aqueous, 1050; diet 242). This study links radionuclide bioaccumulation data obtained in laboratory experiments with radiation dose determined by application of a dosimetry modelling tool, an approach that will enable better linkages to be made between exposure, dose, and effects of radionuclides in organisms.

Helena C. Reinardy; Jean-Louis Teyssie; Ross A. Jeffree; David Copplestone; Theodore B. Henry; Awadhesh N. Jha

2011-01-01T23:59:59.000Z

269

A modified Phase I trial of radiation dose escalation in 3D conformal radiation therapy with concurrent vinorelbine and carboplatin chemotherapy for non-small-cell lung cancer  

Science Journals Connector (OSTI)

......system (VENUS 5014 software, Shanghai Tuoneng Co.) used to design the radiation plan. The convolution...stopped. Grade III radiation pneumonia was defined...DLT. To examine the safety of the 70 Gy dose level...Case Case Case (%) Radiation pneumonia 11 (61......

Qiang Lin; Yue'e Liu; Na Wang; Yuehua Huang; Xiaohui Ge; Xiaocang Ren; Xueji Chen; Jing Hu; Zhijun Guo; Yannan Zhao; Junichi Asaumi

2013-01-01T23:59:59.000Z

270

Nuclear Decay Data in the MIRD (Medical Internal Radiation Dose) Format  

DOE Data Explorer (OSTI)

MIRD is a database of evaluated nuclear decay data for over 2,100 radioactive nuclei. Data are extracted from ENSDF, processed by the program RadList, and used for medical internal radiation dose calculations. When using the MIRD interface, tables of nuclear and atomic radiations from nuclear decay and decay scheme drawings will be produced in the MIRD format from the Evaluated Nuclear Structure Data File (ENSDF) for the specified nuclide. Output may be either HTML-formatted tables and JPEG drawings, PostScript tables and drawings, or PDF tables and drawings.

271

A revised model of the kidney for medical internal radiation dose calculations  

E-Print Network (OSTI)

are frequently the organs receiving the highest level of radioactivity and, therefore, the largest radiation dose. Short lived radiopharmaceuticals, that are now injected in millicurie quantities in nuclear medicine for rapid-sequence imaging of the brain... radionuclides (Appendix B). 17 These include the following radionuclides presently used in nuclear medicine: P-32, Cr-51, Co-57, Ga-67, Tc-99m, In-ill, I-123, Xe-127, I-131, Xe-133, and T1-201. If the radionuclide emits penetrating radiation, the code...

Patel, Jyoti Shivabhai

1988-01-01T23:59:59.000Z

272

Radiation dose estimation in computed tomography examinations using NRPB-SR250 software in aretrospective analysis of a patient population  

Science Journals Connector (OSTI)

......NRPB-SR250 software in aretrospective...fi 1 STUK-Radiation and Nuclear Safety Authority...342:d947. RADIATION DOSE ESTIMATION...NRPB-SR250 SOFTWARE IN A RETROSPECTIVE...of medical radiation exposure...to patients safety, frequent......

E. Salminen; H. Niiniviita; J. Kulmala; H. Mttnen; H. Jrvinen

2012-12-01T23:59:59.000Z

273

Low Dose Radiation Research Program: Comparisons of IR and ROS for  

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

Comparisons of IR and ROS for Induction of Damage to Cells Comparisons of IR and ROS for Induction of Damage to Cells Kathryn D. Held1, Yvonne L. McCarey1, Laurence Tartier1, Elena V. Rusyn1, Giuseppe Schettino2, Melvyn Folkard2, Kevin M. Prise2, and Barry D. Michael2 1Department of Radiation Oncology, Massachusetts General Hospital/Harvard Medical School, Boston, MA 02114; 2Gray Laboratory Cancer Research Trust, Mount Vernon Hospital, Northwood, HA6 2JR, UK Accurate evaluation of the risks associated with exposure to low doses of ionizing radiation (IR) is a major challenge for environmental sciences. Studies on the mechanisms of the actions of low doses of IR are needed to help understand possible risks. IR exerts its effects on cells through production of reactive oxidizing species (ROS) such as ·OH, H2O2 and

274

Low Dose Radiation Stimulates Antioxidant Capacity in the Brain and Lessens  

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

Stimulates Antioxidant Capacity in the Brain and Lessens Stimulates Antioxidant Capacity in the Brain and Lessens Behavioral Symptoms in a 6-OHDA-Induced Rat Model of Parkinson's Disease Mohan Doss Fox Chase Cancer Center Abstract Background: Progressive degeneration of dopaminergic neurons in the substantia nigra (SN) pars compacta results in motor deficits in Parkinson’s disease (PD) patients. Oxidative damage to the nigral dopaminergic neurons has been implicated in the pathogenesis of Parkinson’s disease. Our hypothesis is that low dose radiation induces the production of antioxidants in the brain, which could provide protection to the dopaminergic neurons, potentially leading to prevention or stabilization of PD. The purpose of the study is (1) to determine the effect of low dose radiation on the total antioxidant capacity in SN in

275

TABLES OF RADIATION ABSORBED DOSE TO THE EMBRYO/FETUS FROM RADIOPHARMACEUTICALS  

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

TABLES OF RADIATION ABSORBED DOSE TO THE EMBRYO/FETUS TABLES OF RADIATION ABSORBED DOSE TO THE EMBRYO/FETUS FROM RADIOPHARMACEUTICALS LATEST REVISION DATE: 1/21/98 The material in this document is taken from the Master's thesis of Ms. Joy Russell (University of Tennessee, Master's Degree conferred August 1995). The data below, and the methods and assumptions used to derive them, are published in two documents in the Health Physics Journal (73(5):747-755, 1997 and 73(5):756-769, 1997) and also in the Proceedings of the Sixth International Radiopharmaceutical Dosimetry Symposium. Please contact the center with any questions or comments about the data. Richard E. Toohey, 423-576-3448 phone, 423-576-8673 fax, tooheyr@orau.gov e-mail Audrey T. Stelson, 423-576-3450 phone, 423-576-8673 fax, stelsona@orau.gov e-mail

276

Low Dose Radiation Research Program: Regulation of NF-kB and MnSOD in Low  

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

NF-kB and MnSOD in Low Dose Radiation-Induced Adaptive NF-kB and MnSOD in Low Dose Radiation-Induced Adaptive Responses in Mouse and Human Skin Cells Jian Jian Li School of Health Sciences, Purdue University West Lafayette, Indiana Why this Project? To determine if low dose ionizing radiation-induced adaptive responses in skin cells are mediated by activation of signaling networks. Project Goals To evaluate the signaling networks involving transcription factor NF-kB and the mitochondrial antioxidant protein MnSOD. To determine if NF-kB is activated by low dose radiation in vivo. To determine if NF-kB activation is critical in the pathways that produce adaptive responses. Experimental Approach Cells transfected with NF-kB luciferase responder genes will be used to define a dose-response relationship for activation of the NF-kB gene. NF-kB

277

Radiation Dose and Radiation Protection for Patients and Physicians During Interventional Procedure  

Science Journals Connector (OSTI)

......Radiation Injury in IVR 101 those in the left coronary artery (LCA, AHA #1115: 0.628, AHA #510: 0.694).40) Therefore...criphysicianfactsheet.asp. Published May 10, 2006. 58. Food and Agriculture Organization of the United Nations, International Atomic Energy......

Koichi Chida; Mamoru Kato; Yutaka Kagaya; Masayuki Zuguchi; Haruo Saito; Tadashi Ishibashi; Shoki Takahashi; Shogo Yamada; Yoshihiro Takai

2010-03-01T23:59:59.000Z

278

Radiation dose assessment methodology and preliminary dose estimates to support US Department of Energy radiation control criteria for regulated treatment and disposal of hazardous wastes and materials  

SciTech Connect

This report provides unit dose to concentration levels that may be used to develop control criteria for radionuclide activity in hazardous waste; if implemented, these criteria would be developed to provide an adequate level of public and worker health protection, for wastes regulated under U.S, Environmental Protection Agency (EPA) requirements (as derived from the Resource Conservation and Recovery Act [RCRA] and/or the Toxic Substances Control Act [TSCA]). Thus, DOE and the US Nuclear Regulatory Commission can fulfill their obligation to protect the public from radiation by ensuring that such wastes are appropriately managed, while simultaneously reducing the current level of dual regulation. In terms of health protection, dual regulation of very small quantities of radionuclides provides no benefit.

Aaberg, R.L.; Baker, D.A.; Rhoads, K.; Jarvis, M.F.; Kennedy, W.E. Jr.

1995-07-01T23:59:59.000Z

279

Ionizing Radiation Causes a Dose-Dependent Release of Transforming Growth Factor ? In vitro from Irradiated Xenografts and during Palliative Treatment of Hormone-Refractory Prostate Carcinoma  

Science Journals Connector (OSTI)

...Preclinical Pharmacology Ionizing Radiation Causes a Dose-Dependent Release of...linear function of the radiation dose over the range 0-10 Gy with r2 0...20: 91-5, 2000. Ionizing radiation causes a dose-dependent release of...

Michael Hagan; Adly Yacoub; and Paul Dent

2004-09-01T23:59:59.000Z

280

Effects of Substerilization Doses of Co60 Gamma Radiation on the Cold-Storage Life Extension of Shucked Soft-Shelled Clams and Haddock Fillets  

Science Journals Connector (OSTI)

...000 rad of ionizing radiation. In the dose range from 200,000...000 rad of ionizing radiation. In the dose range from 200,000...000 rad of ionizing radiation. Nevertheless...indicate that in the dose range from 400,000...

E. B. Masurovsky; S. A. Goldblith; J. T. R. Nickerson

1963-05-01T23:59:59.000Z

Note: This page contains sample records for the topic "radiation dose equivalent" 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.


281

Mechanisms underlying cellular responses of cells from haemopoeitic tissue to low dose-low LET radiation  

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

underlying cellular responses of cells from haemopoeitic underlying cellular responses of cells from haemopoeitic tissue to low dose-low LET radiation Munira Kadhim 1 , Sarah Irons 1 , Deborah Bowler 1 , Virginia Serra 1 , Stefania Militi 2 , Kim Chapman 1 1 Genomic Instability Research Group, School of Life Sciences, Oxford Brookes University, Gipsy Lane, Headington, Oxford, Oxfordshire, OX3 0BP, UK 2 Mammalian Genetics Unit, Medical Research Council Harwell, Harwell Science and Innovation Campus, Oxfordshire, OX11 0RD, UK Radiation-induced responses at the cellular and whole body levels are influenced by genetic predisposition, with implications for environmental and potentially, diagnostic exposures. Currently, the extent to which genetic background play a role in the mechanisms and signalling pathways involved in radiation-induced

282

Low Dose Radiation Research Program: DNA Damage in Acutely Irradiated F2  

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

DNA Damage in Acutely Irradiated F2 Mice with a History of Paternal DNA Damage in Acutely Irradiated F2 Mice with a History of Paternal F0 Germline Irradiation Authors: J.E. Baulch and O.G. Raabe Institutions: Center for Health and the Environment, University of California, Davis, CA. The main goal of this grant is to evaluate heritable, transgenerational effects of low dose, low-linear-energy-transfer (LET) radiation (0.1 Gy attenuated 137Cs gamma rays) on Type B spermatogonia in 129SVE mice; wild-type and heterozygous for Ataxia-telangiectasia (AT). The ATM heterozygotes are carriers for a genetic mutation (AT mutated, ATM) that is thought to predispose both humans and mice to radiation sensitivity. Experiments conducted in our laboratory have demonstrated heritable effects of paternal germline exposure to ionizing radiation in mice using 1.0 Gy of

283

Low Dose Ionizing Radiation and HZE Particle Effects on Adult Hippocampal  

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

and HZE Particle Effects on Adult Hippocampal and HZE Particle Effects on Adult Hippocampal Neurogenesis and mRNA Expression Kerry O'Banion University of Rochester School of Medicine & Dentistry Abstract Most of our knowledge about low dose radiation effects relates to DNA damage and chromosomal aberrations that result in cell death or alterations in genetic programs leading to malignancy. In addition To direct DNA damage, there is accumulating evidence that radiation induced alterations in the microenvironment can have significant effects on programs of cell replication and differentiation such as neurogenesis in adult mammalian brain. Adult neurogenesis in the hippocampus is postulated to play an important role in learning and memory and manipulations that alter neurogenesis, including inhibition following radiation exposure, have been

284

Effects of non-lethal doses of ionising radiation on the instrumental behaviour of rats  

Science Journals Connector (OSTI)

The dose-effect dependence of the instrumental behaviour of white rats after a single total ?-exposure (60Co) in the dosage range of 0.05 to 7.0 Gy was studied. Generalised results of seven years of our studies of post-radiation changes of operant behaviour in shuttle (active avoidance of shock ?? negative reinforcement) and in Skinner (drinking reward ?? positive reinforcement) boxes were evaluated weekly for a two-month period after exposure. The dose dependence, obtained using these two behavioural paradigms, displays a non-linear pattern. Three regions with different characteristic patterns of the observed effects were found: performance declines relative to control animals after exposure to doses up to 1.0 Gy; performance increases at doses in the range from 1.0 to 3.0 Gy; and again declines with dose increases up to 7.0 Gy. Possible underlying mechanisms, particularly the role of additional stress caused by animal testing, are discussed.

Eugene V. Tukalenko; Vyacheslav V. Varetsky; Olexander G. Rakochi; Inna R. Dmitrieva; Mikola U. Makarchuk

2007-01-01T23:59:59.000Z

285

Low Dose Radiation Research Program: Multi-cellular Crosstalk in Radiation  

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

About this Project About this Project Multi-cellular Crosstalk in Radiation Damage Technical Abstracts 2006 Workshop: Low-LET Bystander Effects in Cells In Vitro Are Significantly Less Than Published For High-LET Radiation Blakely, E.A., Thompson, A.C., Chang, P., Schwarz, R.I., Bjornstad, K., Rosen, C., Wisnewski, C., and Mocherla, D. 2005 Workshop: X-ray Microbeam Bystander Studies with Human Mammary Epithelial Cells and Fibroblasts Blakely, E.A., Schwarz, R.I., Thompson, A.C., Bjornstad, K.A., Chang, P.Y., Rosen, C.J., Sudar, D., Romano, R., and Parvin, B. 2003 Workshop: 12.5 keV X-ray Microbeam Bystander Studies with Human Mammary Epithelial Cells and Fibroblasts Blakely, E.A., Schwarz, R.I., Thompson, A.C., Bjornstad, K.A., Chang, P.Y., Rosen, C.J., and Sudar, D. 2001 Workshop:

286

Significance of certain rustler aquifer parameters for predicting long-term radiation doses from WIPP  

SciTech Connect

This report considers some aspects of the radionuclide transport modeling presented in documents published by the US Department of Energy (DOE) regarding the Waste Isolation Pilot Plant (WIPP) nuclear waste repository proposed for development in Southeastern New Mexico. The radionuclide transport modeling is used to predict worst possible consequences of a WIPP repository breach event in which waste enters groundwater. The aim of this report is to determine whether plausible changes in the parameters used by DOE to describe the flow of groundwater near the WIPP site could result in: (a) significantly faster radionuclide movement in groundwater; and (b) significantly higher concentrations of radionuclides in Pecos River water and correspondingly higher radiation doses than predicted by DOE. The conclusion reached is that while plausible changes in hydrologic conditions and waste-rock interactions might result in a significant reduction in the time it takes for radionuclides to reach the Pecos River, the shorter travel times do not result in significant increases in the estimated concentrations of radionuclides in the Pecos River nor in the radiation doses associated with the use of such water. Other ways in which parameter changes might affect these concentrations and doses are mentioned in the Conclusions section of the report, but are not the subject of this analysis.

Wofsy, C

1980-09-01T23:59:59.000Z

287

Retrospective Cohort Study of Bronchial Doses and Radiation-Induced Atelectasis After Stereotactic Body Radiation Therapy of Lung Tumors Located Close to the Bronchial Tree  

SciTech Connect

Purpose: To evaluate the doseresponse relationship between radiation-induced atelectasis after stereotactic body radiation therapy (SBRT) and bronchial dose. Methods and Materials: Seventy-four patients treated with SBRT for tumors close to main, lobar, or segmental bronchi were selected. The association between incidence of atelectasis and bronchial dose parameters (maximum point-dose and minimum dose to the high-dose bronchial volume [ranging from 0.1 cm{sup 3} up to 2.0 cm{sup 3}]) was statistically evaluated with survival analysis models. Results: Prescribed doses varied between 4 and 20 Gy per fraction in 2-5 fractions. Eighteen patients (24.3%) developed atelectasis considered to be radiation-induced. Statistical analysis showed a significant correlation between the incidence of radiation-induced atelectasis and minimum dose to the high-dose bronchial volumes, of which 0.1 cm{sup 3} (D{sub 0.1cm3}) was used for further analysis. The median value of D{sub 0.1cm3} (?/? = 3 Gy) was EQD{sub 2,LQ} = 147 Gy{sub 3} (range, 20-293 Gy{sub 3}). For patients who developed atelectasis the median value was EQD{sub 2,LQ} = 210 Gy{sub 3}, and for patients who did not develop atelectasis, EQD{sub 2,LQ} = 105 Gy{sub 3}. Median time from treatment to development of atelectasis was 8.0 months (range, 1.1-30.1 months). Conclusion: In this retrospective study a significant doseresponse relationship between the incidence of atelectasis and the dose to the high-dose volume of the bronchi is shown.

Karlsson, Kristin, E-mail: kristin.karlsson@karolinska.se [Department of Medical Physics, Karolinska University Hospital, Stockholm (Sweden); Department of Oncology-Pathology, Karolinska Institute, Stockholm (Sweden); Nyman, Jan [Department of Oncology, Sahlgrenska University Hospital, Gothenburg (Sweden); Baumann, Pia; Wersll, Peter [Department of Oncology, Radiumhemmet, Karolinska University Hospital, Stockholm (Sweden); Department of Oncology-Pathology, Karolinska Institute, Stockholm (Sweden); Drugge, Ninni [Department of Radiation Physics, Sahlgrenska University Hospital, Gothenburg (Sweden); Gagliardi, Giovanna [Department of Medical Physics, Karolinska University Hospital, Stockholm (Sweden); Department of Oncology-Pathology, Karolinska Institute, Stockholm (Sweden); Johansson, Karl-Axel [Department of Radiation Physics, Sahlgrenska University Hospital, Gothenburg (Sweden); Persson, Jan-Olov [Statistical Research Group, Mathematical Statistics, Stockholm University, Stockholm (Sweden); Rutkowska, Eva [Physics Department, Clatterbridge Cancer Centre, Wirral (United Kingdom); Tullgren, Owe [Department of Oncology, Radiumhemmet, Karolinska University Hospital, Stockholm (Sweden); Department of Oncology-Pathology, Karolinska Institute, Stockholm (Sweden); Lax, Ingmar [Department of Medical Physics, Karolinska University Hospital, Stockholm (Sweden); Department of Oncology-Pathology, Karolinska Institute, Stockholm (Sweden)

2013-11-01T23:59:59.000Z

288

Correlation of radiation absorbed dose to the human thyroid using the FBX dosimeter and external probe techniques  

E-Print Network (OSTI)

Internal Radiaion Dose Reports (MIRD) of the Society of Nuclear Medicine. The dosimeter exhibited a similar response to that. obtained in the research of Benedetto who also correlated his results to ca)culat)ons made using MIRD techniques (Beg4k... that would be able to assess the radiation absorbed dose produced by radioisotopes in both nuclear medicine and due to accidental internal deposition of radionuclides to radiation workers or to members of the general public would have many desirable...

Bateman, Sarah Caroline Louisa

2012-06-07T23:59:59.000Z

289

Impact of Internal Metallic Ports in Temporary Tissue Expanders on Postmastectomy Radiation Dose Distribution  

SciTech Connect

Purpose: Temporary tissue expanders (TTE) with an internal magnetic metal port (IMP) have been increasingly used for breast reconstruction in post-mastectomy patients who receive radiation therapy (XRT). We evaluated XRT plans of patients with IMP to determine its effect on XRT dose distribution. Methods and Materials: Original treatment plans with CT simulation scans of 24 consecutive patients who received XRT (ORI), planned without heterogeneity corrections, to a reconstructed breast containing an IMP were used. Two additional treatment plans were then generated: one treatment plan with the IMP assigned the electron density of the rare earth magnet, nickel plated neodymium-iron-boron (HET), and a second treatment plan with the IMP assigned a CT value of 1 to simulate a homogeneous breast without an IMP (BRS). All plans were prescribed 50 Gy to the reconstructed breast (CTV). Results: CTV coverage by 50 Gy was significantly lower in the HET (mean 87.7% CTV) than in either the ORI (mean 99.7% CTV, P<.001) or BRS plans (mean 95.0% CTV, P<.001). The effect of the port was more pronounced on CT slices containing the IMP with prescription dose coverage of the CTV being less in the HET than in either ORI (mean difference 33.6%, P<.01) or BRS plans (mean difference 30.1%, P<.001). HET had a less homogeneous and conformal dose distribution than BRS or ORI. Conclusion: IMPs increase dose heterogeneity and reduce dose to the breast CTV through attenuation of the beam. For optimal XRT treatment, heterogeneity corrections should be used in XRT planning for patients with TTE with IMP, as the IMP impacts dose distribution.

Chen, Susie A.; Ogunleye, Tomiwa; Dhabbaan, Anees [Department of Radiation Oncology, Winship Cancer Institute, Emory University, Atlanta, Georgia (United States)] [Department of Radiation Oncology, Winship Cancer Institute, Emory University, Atlanta, Georgia (United States); Huang, Eugene H. [North Coast Cancer Care, Sandusky, Ohio (United States)] [North Coast Cancer Care, Sandusky, Ohio (United States); Losken, Albert [Division of Plastic Surgery and Reconstructive Surgery, Department of Surgery, Emory University, Atlanta, Georgia (United States)] [Division of Plastic Surgery and Reconstructive Surgery, Department of Surgery, Emory University, Atlanta, Georgia (United States); Gabram, Sheryl [Division of Surgical Oncology, Department of Surgery, Emory University, Atlanta, Georgia (United States)] [Division of Surgical Oncology, Department of Surgery, Emory University, Atlanta, Georgia (United States); Davis, Lawrence [Department of Radiation Oncology, Winship Cancer Institute, Emory University, Atlanta, Georgia (United States)] [Department of Radiation Oncology, Winship Cancer Institute, Emory University, Atlanta, Georgia (United States); Torres, Mylin A., E-mail: matorre@emory.edu [Department of Radiation Oncology, Winship Cancer Institute, Emory University, Atlanta, Georgia (United States)

2013-03-01T23:59:59.000Z

290

Radiological Dose Assessment 8 2013 SITE ENVIRONMENTAL REPORT8-1  

E-Print Network (OSTI)

. The effective dose equivalent (EDE) from air emissions in 2013 was estimated as 3.65E-01 mrem (3.6 Sv dose limit of 10 mrem (100 Sv). In addition, the dose from the ingestion pathway was estimated as 2 the natural background radiation. The average annual external dose from on-site ambient sources was 66 � 8

291

Standard Test Method for Measuring Dose for Use in Linear Accelerator Pulsed Radiation Effects Tests  

E-Print Network (OSTI)

1.1 This test method covers a calorimetric measurement of the total dose delivered in a single pulse of electrons from an electron linear accelerator or a flash X-ray machine (FXR, e-beam mode) used as an ionizing source in radiation-effects testing. The test method is designed for use with pulses of electrons in the energy range from 10 to 50 MeV and is only valid for cases in which both the calorimeter and the test specimen to be irradiated arethin compared to the range of these electrons in the materials of which they are constructed. 1.2 The procedure described can be used in those cases in which (1) the dose delivered in a single pulse is 5 Gy (matl) (500 rd (matl)) or greater, or (2) multiple pulses of a lower dose can be delivered in a short time compared to the thermal time constant of the calorimeter. Matl refers to the material of the calorimeter. The minimum dose per pulse that can be acceptably monitored depends on the variables of the particular test, including pulse rate, pulse uniformity...

American Society for Testing and Materials. Philadelphia

2011-01-01T23:59:59.000Z

292

Magnetic Resonance Imaging-Based Radiation-Absorbed Dose Estimation of 166Ho Microspheres in Liver Radioembolization  

Science Journals Connector (OSTI)

Purpose To investigate the potential of magnetic resonance imaging (MRI) for accurate assessment of the three-dimensional 166Ho activity distribution to estimate radiation-absorbed dose distributions in 166Ho-loaded poly (L-lactic acid) microsphere (166Ho-PLLA-MS) liver radioembolization. Methods and Materials MRI, computed tomography (CT), and single photon emission CT (SPECT) experiments were conducted on an anthropomorphic gel phantom with tumor-simulating gel samples and on an excised human tumor-bearing liver, both containing known amounts of 166Ho-PLLA-MS. Three-dimensional radiation-absorbed dose distributions were estimated at the voxel level by convolving the 166Ho activity distribution, derived from quantitative MRI data, with a 166Ho dose point-kernel generated by MCNP (Monte Carlo N-Particle transport code) and from Medical Internal Radiation Dose Pamphlet 17. MRI-based radiation-absorbed dose distributions were qualitatively compared with CT and autoradiography images and quantitatively compared with SPECT-based dose distributions. Both MRI- and SPECT-based activity estimations were validated against dose calibrator measurements. Results Evaluation on an anthropomorphic phantom showed that MRI enables accurate assessment of local 166Ho-PLLA-MS mass and activity distributions, as supported by a regression coefficient of 1.05 and a correlation coefficient of 0.99, relating local MRI-based mass and activity calculations to reference values obtained with a dose calibrator. Estimated MRI-based radiation-absorbed dose distributions of 166Ho-PLLA-MS in an exvivo human liver visually showed high correspondence to SPECT-based radiation-absorbed dose distributions. Quantitative analysis revealed that the differences in local and total amounts of 166Ho-PLLA-MS estimated by MRI, SPECT, and the dose calibrator were within 10%. Excellent agreement was observed between MRI- and SPECT-based dosevolume histograms. Conclusions Quantitative MRI was demonstrated to provide accurate three-dimensional 166Ho-PLLA-MS activity distributions, enabling localized intrahepatic radiation-absorbed dose estimation by convolution with a 166Ho dose point-kernel for liver radioembolization treatment optimization and evaluation.

Peter R. Seevinck; Gerrit H. van de Maat; Tim C. de Wit; Maarten A.D. Vente; Johannes F.W. Nijsen; Chris J.G. Bakker

2012-01-01T23:59:59.000Z

293

Evaluation and Control of Radiation Dose to the Embryo/Fetus Guide for Use with Title 10, Code of Federal Regulations, Part 835, Occupational Radiation Protection  

Directives, Delegations, and Requirements

This Guide provides an acceptable methodology for establishing and operating a program to control fetal exposure to ionizing radiation and evaluate the resultant dose that will comply with U.S. Department of Energy (DOE) requirements specified in Title 10 of the Code of Federal Regulations (CFR), Part 835, Occupational Radiation Protection (DOE 1998), hereinafter referred to as 10 CFR 835.

1999-04-29T23:59:59.000Z

294

Low Dose Radiation Research Program: A Variable Energy Soft X-ray  

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

Variable Energy Soft X-ray Microprobe to Investigate Mechanisms of Variable Energy Soft X-ray Microprobe to Investigate Mechanisms of the Radiation Induced Bystander Effect. Authors: Melvyn Folkard, Borivoj Vojnovic, Giuseppe Schettino, Kevin M Prise and Barry D Michael. Institutions: Gray Cancer Institute. We are currently engaged on two projects in the Low-dose Program: "Low dose studies with focused X-rays in cell and tissue models: mechanisms of bystander and genomic instability responses" (DE-FG07-99ER62877) and "Mechanistic modeling of bystander effects: An integrated theoretical and experimental approach" (DE-FG02-02ER63305). Central to both of these studies is a unique micro irradiation facility that uses ultrasoft X-rays focused to a sub micron beam for individual cell and sub cellular targeting. This facility allows us to selectively irradiate individual

295

Impact of Gastric Filling on Radiation Dose Delivered to Gastroesophageal Junction Tumors  

SciTech Connect

Purpose: This study examined the impact of gastric filling variation on target coverage of gastroesophageal junction (GEJ) tumors in three-dimensional conformal radiation therapy (3DCRT), intensity-modulated radiation therapy (IMRT), or IMRT with simultaneous integrated boost (IMRT-SIB) plans. Materials and Methods: Eight patients previously receiving radiation therapy for esophageal cancer had computed tomography (CT) datasets acquired with full stomach (FS) and empty stomach (ES). We generated treatment plans for 3DCRT, IMRT, or IMRT-SIB for each patient on the ES-CT and on the FS-CT datasets. The 3DCRT and IMRT plans were planned to 50.4 Gy to the clinical target volume (CTV), and the same for IMRT-SIB plus 63.0 Gy to the gross tumor volume (GTV). Target coverage was evaluated using dose-volume histogram data for patient treatments simulated with ES-CT sets, assuming treatment on an FS for the entire course, and vice versa. Results: FS volumes were a mean of 3.3 (range, 1.7-7.5) times greater than ES volumes. The volume of the GTV receiving >=50.4 Gy (V{sub 50.4Gy}) was 100% in all situations. The planning GTV V{sub 63Gy} became suboptimal when gastric filling varied, regardless of whether simulation was done on the ES-CT or the FS-CT set. Conclusions: Stomach filling has a negligible impact on prescribed dose delivered to the GEJ GTV, using either 3DCRT or IMRT planning. Thus, local relapses are not likely to be related to variations in gastric filling. Dose escalation for GEJ tumors with IMRT-SIB may require gastric filling monitoring.

Bouchard, Myriam, E-mail: mybouchard@gmail.co [Department of Radiation Physics, University of Texas M. D. Anderson Cancer Center, Houston, TX (United States); McAleer, Mary Frances [Department of Radiation Oncology, University of Texas M. D. Anderson Cancer Center, Houston, TX (United States); Starkschall, George, E-mail: gstarksc@mdanderson.or [Department of Radiation Physics, University of Texas M. D. Anderson Cancer Center, Houston, TX (United States)

2010-05-01T23:59:59.000Z

296

Radiation dose rates now and in the future for residents neighboring restricted areas of the Fukushima Daiichi Nuclear Power Plant  

Science Journals Connector (OSTI)

...background radiation doses in Japan. Finally, health risk...recruited from 63 of 151 households (42%). In Minamisomas Haramachi...radon concentration in Japan . J Environ Radioact 65...indoor Rn concentration in Japan . J Environ Radioact 45...International Atomic Energy Agency (2011) Radiation...

Kouji H. Harada; Tamon Niisoe; Mie Imanaka; Tomoyuki Takahashi; Katsumi Amako; Yukiko Fujii; Masatoshi Kanameishi; Kenji Ohse; Yasumichi Nakai; Tamami Nishikawa; Yuuichi Saito; Hiroko Sakamoto; Keiko Ueyama; Kumiko Hisaki; Eiji Ohara; Tokiko Inoue; Kanako Yamamoto; Yukiyo Matsuoka; Hitomi Ohata; Kazue Toshima; Ayumi Okada; Hitomi Sato; Toyomi Kuwamori; Hiroko Tani; Reiko Suzuki; Mai Kashikura; Michiko Nezu; Yoko Miyachi; Fusako Arai; Masanori Kuwamori; Sumiko Harada; Akira Ohmori; Hirohiko Ishikawa; Akio Koizumi

2014-01-01T23:59:59.000Z

297

Low Dose Radiation Research Program: A Variable-Energy Soft X-Ray  

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

A Variable-Energy Soft X-Ray Microprobe to Investigate Mechanisms of A Variable-Energy Soft X-Ray Microprobe to Investigate Mechanisms of the Radiation-Induced Bystander Effect. Authors: Melvyn Folkard, Borivoj Vojnovic, Giuseppe Schettino, Kirk Atkinson, Kevin M Prise, Barry D Michael Institutions: Gray Cancer Institute, PO BO Box100, Mount Vernon Hospital, Northwood, HA6 2JR, UK The Gray Cancer Institute (GCI) has pioneered the use of X-ray focussing techniques to develop systems for micro-irradiating individual cells and sub-cellular targets. Our prototype X-ray microprobe was developed alongside our existing charged-particle microbeam to address problems specific to low LET radiations, or where very precise targeting accuracy and dose delivery are required. This facility was optimised for focusing 278 eV CK X-rays; however there are a number of reasons for extending the

298

Low Dose Radiation Research Program: A Paracrine Signal Mediates The Cell  

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

A Paracrine Signal Mediates The Cell Transformation Response To Low A Paracrine Signal Mediates The Cell Transformation Response To Low Dose Gamma Radiation in JB6 Cells. Authors: Thomas J. Weber,1 Robert W. Siegel,2 Lye M. Markillie,1 William B. Chrisler,1 Xingye C. Lei,3 and Nancy H. Colburn4 Institutions: 1Cell Biology and Biochemistry, Pacific Northwest National Laboratory, Richland, Washington. 2Protein Function, Pacific Northwest National Laboratory, Richland, Washington. 3Statistical and Mathematical Sciences, Pacific Northwest National Laboratory, Richland, Washington. 4Gene Regulation Section, Laboratory of Cancer Prevention, National Cancer Institute at Frederick, Frederick, Maryland. The carcinogenic response to radiation is complex and may involve adaptive cellular responses as well as a bystander effect mediated by paracrine or

299

A hybrid approach for rapid, accurate, and direct kilovoltage radiation dose calculations in CT voxel space  

SciTech Connect

Purpose: To develop and validate a fast and accurate method that uses computed tomography (CT) voxel data to estimate absorbed radiation dose at a point of interest (POI) or series of POIs from a kilovoltage (kV) imaging procedure. Methods: The authors developed an approach that computes absorbed radiation dose at a POI by numerically evaluating the linear Boltzmann transport equation (LBTE) using a combination of deterministic and Monte Carlo (MC) techniques. This hybrid approach accounts for material heterogeneity with a level of accuracy comparable to the general MC algorithms. Also, the dose at a POI is computed within seconds using the Intel Core i7 CPU 920 2.67 GHz quad core architecture, and the calculations are performed using CT voxel data, making it flexible and feasible for clinical applications. To validate the method, the authors constructed and acquired a CT scan of a heterogeneous block phantom consisting of a succession of slab densities: Tissue (1.29 cm), bone (2.42 cm), lung (4.84 cm), bone (1.37 cm), and tissue (4.84 cm). Using the hybrid transport method, the authors computed the absorbed doses at a set of points along the central axis and x direction of the phantom for an isotropic 125 kVp photon spectral point source located along the central axis 92.7 cm above the phantom surface. The accuracy of the results was compared to those computed with MCNP, which was cross-validated with EGSnrc, and served as the benchmark for validation. Results: The error in the depth dose ranged from -1.45% to +1.39% with a mean and standard deviation of -0.12% and 0.66%, respectively. The error in the x profile ranged from -1.3% to +0.9%, with standard deviations of -0.3% and 0.5%, respectively. The number of photons required to achieve these results was 1x10{sup 6}. Conclusions: The voxel-based hybrid method evaluates the LBTE rapidly and accurately to estimate the absorbed x-ray dose at any POI or series of POIs from a kV imaging procedure.

Kouznetsov, Alexei; Tambasco, Mauro [Department of Physics and Astronomy, University of Calgary, Calgary, Alberta T2N 1N4 (Canada); Department of Physics and Astronomy and Department of Oncology, University of Calgary and Tom Baker Cancer Centre, 1331-29 Street NW Calgary, Alberta T2N 4N2 (Canada)

2011-03-15T23:59:59.000Z

300

int. j. radiat. biol 2002, vol. 78, no. 7, 593 604 Do low dose-rate bystander eVects in uence domestic radon risks?  

E-Print Network (OSTI)

int. j. radiat. biol 2002, vol. 78, no. 7, 593± 604 Do low dose-rate bystander eVects in uence that bystander radon risk estimation. eVects can be induced by high-LET radiation even Conclusions : Bystander e of inverse dose-rate eVects by high- exposed to low doses of low-LET radiation (SawantLET radiation

Brenner, David Jonathan

Note: This page contains sample records for the topic "radiation dose equivalent" 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

Specific gene expression by extremely low-dose ionizing radiation which related to enhance proliferation of normal human diploid cells  

Science Journals Connector (OSTI)

We demonstrated that X-ray irradiation at low doses of between 2 and 5 cGy stimulated proliferation of a normal human diploid. At low doses of between 2 and 5 cGy, ERK1/2 was phosphorylated as efficiently as at higher doses between 50 and 100 cGy of X-rays, while the p53 protein level was not increased by doses below 50 cGy. On the other hand, the p53 protein was efficiently accumulated at higher doses of X-ray more than 100 cGy. ERK1/2 was phosphorylated by doses over 50 cGy with increasing doses. We found that activated ERK1/2 augmented phosphorylation of the Elk-1 protein. Furthermore, over expression of ERK2 in NCI-H1299, and human lung carcinoma cells, potentiated enhanced proliferation, while down-regulation of ERK2 using the anti-sense ERK2 gene abrogated the stimulative effect of low-dose irradiation. These results indicate that a limited range of low-dose ionizing radiation differentially activate ERK1/2 kinases, which causes enhanced proliferation of cells receiving very low doses of ionizing radiation.

Masami Watanabe; Keiji Suzuki; Seiji Kodama

2002-01-01T23:59:59.000Z

302

Prevention of Low Dose Radiation-Induced Genomic Instability with Clinically Relevant Non-Protein Thiols and Vitamin E.  

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

Prevention of Low Dose Radiation-Induced Genomic Instability with Clinically Relevant Prevention of Low Dose Radiation-Induced Genomic Instability with Clinically Relevant Non-Protein Thiols and Vitamin E. J.S. Murley 1 , Y. Kataoka 1 , W.F. Morgan 2 , and D.J. Grdina 1 . The University of Chicago, Chicago, IL 1 , The University of Maryland Medical School, Baltimore, MD 2 Induced or delayed radioprotection is a novel phenomenon that shares many similarities with the low dose radiation-induced radiobiological phenomenon referred to as the adaptive response. Induced or delayed radioprotection is defined as an enhancement in the radiation resistance of cells at long times following their exposure to non-protein thiols (NPT) such as WR1065, the free thiol form of amifostine. This effect is the result of the induction of a cascade of intracellular

303

Whole Genome Analysis of Functional Protein Binding Sites and DNA Methylation: Application to p53 and Low Dose Ionizing Radiation.  

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

Whole Genome Analysis of Functional Protein Binding Sites and DNA Methylation: Whole Genome Analysis of Functional Protein Binding Sites and DNA Methylation: Application to p53 and Low Dose Ionizing Radiation. Krassimira Botcheva, John J. Dunn and Carl W. Anderson Biology Department, Brookhaven National Laboratory, Upton, NY 11973, USA The effects of exposure to low doses of ionizing radiation on humans results largely from changes in gene expression mediated by the activation of sequence-specific DNA binding proteins (transcription factors) as well as changes to other chromosomal proteins and perhaps to DNA. To develop a molecular understanding of the consequences of exposures to low doses of ionizing radiation, it will be necessary to understanding where radiation-activated transcription factors bind in whole genomes and how

304

Effect of low-dose, low-LET γ-radiation and BaP injection on pulmonary  

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

low-dose, low-LET γ-radiation and BaP injection on pulmonary low-dose, low-LET γ-radiation and BaP injection on pulmonary immunity in A/J mice K. Gott Lovelace Respiratory Research Institute Abstract Introduction: Low-dose, low-linear-energy-transfer (LET) radiation (LDR; < 100 mGy) activates the immune response (Nowosielska et al., 2006), presumably via epigenetic pathways (Scott et al., 2009) and has been implicated as suppressing both alpha-radiation-induced and smoking-related lung cancer (Scott et al. 2009). One of the hypothesized adaptive-response mechanisms by which LDR does so is by activating immune cell function in the lung, which would then increase their anti-cancer surveillance function (Liu, 2007; Bogdandi et al., 2010). One measure of activated immune cell function is their expression of markers on their cell surface that are

305

Estimation of Radiation Resistance Values of Microorganisms in Food Products  

Science Journals Connector (OSTI)

...Weibull 12D equivalent of a radiation process, or the minimal radiation dose (MRD), for cured ham...experimental sterilizing dose (ESD) and the Schmidt-Nank...9 Printed in U.S.A Estimation of Radiation Resistance Values of Microorganisms...

Abe Anellis; Stanley Werkowski

1968-09-01T23:59:59.000Z

306

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

SciTech Connect

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

Balmain, Allan [University of California, San Francisco; Song, Ihn Young [University of California, San Francisco

2013-05-15T23:59:59.000Z

307

Reduced Kilovoltage in Computed TomographyGuided Intervention in a Community Hospital: Effect on the Radiation Dose  

Science Journals Connector (OSTI)

AbstractPurpose The purpose of this study was to determine whether low-kilovoltage (80 or 100 kV) computed tomography (CT)-guided interventions performed in a community-based hospital are feasible and to compare radiation exposure incurred with conventional 120 kV potential. Materials and Methods Effective doses (ED) received by patients who underwent CT-guided intervention were analysed before and after a low-dose kilovoltage protocol was instituted in our department. We performed CT-guided procedures of 93 consecutive patients by using conventional 120-kV tube voltage (50 patients) and a low voltage of 80 or 100 kV for the remainder of this cohort. Automatic tube current modulation was enabled to obtain the best image quality. Procedure details were prospectively recorded and included examination site and type, slice width, tube voltage and current, dose length product, volume CT dose index, and size-specific dose estimate. Dose length product was converted to ED to account for radiosensitivity of specific organs. Statistical comparisons with test differences in the ED, volume CT dose index, size-specific dose estimate, and effective diameter (patient size) were made by using the Student t test. Results All but 6 of the procedures performed at 80 kV were successful, for a success rate of 86%. At lower voltages, the ED was significantly (P dose radiation technique by using 80 or 100 kV results in a high technical success rate for pelvic, chest, and abdomen CT-guided interventional procedures, although dramatically decreasing radiation exposure. There was no significant difference in effective diameter (patient size) between the conventional and the low-dose groups, which would suggest that dose reduction was indeed a result of kVp change and not patient size.

Saman Rezazadeh; Steven J. Co; Simon Bicknell

2014-01-01T23:59:59.000Z

308

Radiation Doses to Members of the U.S. Population from Ubiquitous Radionuclides in the Body: Part 3, Results, Variability, and Uncertainty  

SciTech Connect

This paper is part three of a three-part series investigating annual effective doses to residents of the United States from intakes of ubiquitous radionuclides, including radionuclides occurring naturally, radionuclides whose concentrations are technologically enhanced, and anthropogenic radionuclides. The radionuclides of interest are the 238U series (14 nuclides), the actinium series (headed by 235U; 11 nuclides), and the 232Th series (11 nuclides); primordial radionuclides 87Rb and 40K; cosmogenic and fallout radionuclides 14C and 3H; and purely anthropogenic radionuclides 137Cs-137mBa, 129I and 90Sr-90Y. This series of papers explicitly excludes intakes from inhaling 222Rn, 220Rn, and their short-lived decay products; it also excludes intakes of radionuclides in occupational and medical settings. Part one reviewed, summarized, characterized, and grouped all published and some unpublished data for U.S. residents on ubiquitous radionuclide concentrations in tissues and organs. Part two described the methods used to organize the data collected in part one and segregate it into the ages and genders defined by the study, imputed missing values from the existing data, apportioned activity in bone, and imputed activity in hollow organ contents and the remainder of the body. This paper estimates equivalent doses to target tissues from source regions and maps target tissues to lists of tissues with International Commission on Radiation Protection (ICRP) tissue-weighting factors or to surrogate tissue regions when there is no direct match. Effective doses, using ICRP tissue-weighting factors recommended in 1977, 1990, and 2007, are then calculated, and an upper bound of variability of the effective dose is estimated by calculating the average coefficients of variation (CV), assuming all variance is due to variability. Most of the data were for adult males, whose average annual effective dose is estimated to be 337 ?Sv (CV = 0.65, geometric mean = 283 ?Sv, geometric standard deviation sG = 1.81) using 2007 ICRP tissue-weighting factors. This result is between the National Council on Radiation Protection & Measurements 1987 estimate of 390 ?Sv (using 1977 wTs) and its 2009 estimate of 285 ?Sv (using 2007 wTs) and is higher than the United Nations Scientific Committee on the Effects of Atomic Radiations 2000 estimate of 310 ?Sv (using 1990 wTs). The methods and software developed for this project are sufficiently detailed and sufficiently general to be usable with autopsy data from any or all countries.

Watson, David J.; Strom, Daniel J.

2011-02-25T23:59:59.000Z

309

rev November 2004 Radiation Safety Manual Section 6 -Personnel Exposure and Monitoring  

E-Print Network (OSTI)

. Estimating Fetal Dose Equivalent .................................................6-10 a. Positionrev November 2004 Radiation Safety Manual Section 6 - Personnel Exposure and Monitoring Page 6-1 Contents .............................................................................6-1 A. Radiation

Wilcock, William

310

Impact of Dose to the Bladder Trigone on Long-Term Urinary Function After High-Dose Intensity Modulated Radiation Therapy for Localized Prostate Cancer  

SciTech Connect

Purpose: To determine the potential association between genitourinary (GU) toxicity and planning dosevolume parameters for GU pelvic structures after high-dose intensity modulated radiation therapy in localized prostate cancer patients. Methods and Materials: A total of 268 patients who underwent intensity modulated radiation therapy to a prescribed dose of 86.4 Gy in 48 fractions during June 2004-December 2008 were evaluated with the International Prostate Symptom Score (IPSS) questionnaire. Dosevolume histograms of the whole bladder, bladder wall, urethra, and bladder trigone were analyzed. The primary endpoint for GU toxicity was an IPSS sum increase ?10 points over baseline. Univariate and multivariate analyses were done by the Kaplan-Meier method and Cox proportional hazard models, respectively. Results: Median follow-up was 5 years (range, 3-7.7 years). Thirty-nine patients experienced an IPSS sum increase ?10 during follow-up; 84% remained event free at 5 years. After univariate analysis, lower baseline IPSS sum (P=.006), the V90 of the trigone (P=.006), and the maximal dose to the trigone (P=.003) were significantly associated with an IPSS sum increase ?10. After multivariate analysis, lower baseline IPSS sum (P=.009) and increased maximal dose to the trigone (P=.005) remained significantly associated. Seventy-two patients had both a lower baseline IPSS sum and a higher maximal dose to the trigone and were defined as high risk, and 68 patients had both a higher baseline IPSS sum and a lower maximal dose to the trigone and were defined as low risk for development of an IPSS sum increase ?10. Twenty-one of 72 high-risk patients (29%) and 5 of 68 low-risk patients (7%) experienced an IPSS sum increase ?10 (P=.001; odds ratio 5.19). Conclusions: The application of hot spots to the bladder trigone was significantly associated with relevant changes in IPSS during follow-up. Reduction of radiation dose to the lower bladder and specifically the bladder trigone seems to be associated with a reduction in late GU toxicity.

Ghadjar, Pirus; Zelefsky, Michael J.; Spratt, Daniel E. [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Munck af Rosenschld, Per; Oh, Jung Hun; Hunt, Margie [Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Kollmeier, Marisa [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Happersett, Laura; Yorke, Ellen; Deasy, Joseph O. [Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Jackson, Andrew, E-mail: jacksona@mskcc.org [Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, New York (United States)

2014-02-01T23:59:59.000Z

311

Forbush decrease effects on radiation dose received on-board aeroplanes  

Science Journals Connector (OSTI)

......information provided by the US FAA to promote radiation safety for air carrier crew members. Radiat...Cosmic Radiation Humans Monte Carlo Method Radiation Dosage Radiation Monitoring methods Software Solar Activity...

P. Lantos

2005-12-01T23:59:59.000Z

312

Assessment of retrospective dose estimation, with fluorescence in situ hybridization (FISH), of six victims previously exposed to accidental ionizing radiation  

Science Journals Connector (OSTI)

Abstract The present study aims to evaluate the use of the fluorescence in situ hybridization (FISH) translocation assay for retrospective dose estimation of acute accidental exposure to radiation in the past. Reciprocal translocation analysis by FISH with three whole-chromosome probes was performed on normal peripheral blood samples. Samples were irradiated with 05Gy 60Co ?-rays in vitro, and doseeffect curves were established. FISH-based translocation analyses for six accident victims were then performed, and biological doses were estimated retrospectively by comparison with the doseeffect curves. Reconstructed doses by FISH were compared with estimated doses obtained by analysis of di-centrics performed soon after exposure, or with dose estimates from tooth-enamel electron paramagnetic resonance (EPR) data obtained at the same time as the FISH analysis. Follow-up FISH analyses for an adolescent victim were performed. Results showed that doseeffect curves established in the present study follow a linear-quadratic model, regardless of the background translocation frequency. Estimated doses according to two doseeffect curves for all six victims were similar. FISH dose estimations of three adult victims exposed to accidental radiation less than a decade prior to analysis (3, 6, or 7 years ago) were consistent with those estimated with tooth-enamel EPR measurements or analyses of di-centrics. Estimated doses of two other adult victims exposed to radiation over a decade prior to analysis (16 or 33 years ago) were underestimated and two to three times lower than the values obtained from analysis of di-centrics or tooth-enamel EPR. Follow-up analyses of the adolescent victim showed that doses estimated by FISH analysis decrease rapidly over time. Therefore, the accuracy of dose estimates by FISH is acceptable only when analysis is performed less than 7 years after exposure. Measurements carried out more than a decade after exposure through FISH analysis resulted in underestimation of the biological doses compared with values obtained through analysis of di-centrics and tooth-enamel EPR.

Qing-Jie Liu; Xue Lu; Xiao-Tao Zhao; Jiang-Bin Feng; Yu-Min L; En-Hai Jiang; Shu-Lan Zhang; De-Qing Chen; Ting-Zhen Jia; Li Liang

2014-01-01T23:59:59.000Z

313

BioDoser: Improved dose-estimation software for biological radiation dosimetry  

Science Journals Connector (OSTI)

This paper introduces a software program that was developed with the aims to improve the efficiency and veracity of calibration curve fitting and data processing in radiation biological dosimetry and other biological experiments, and which is termed BioDoser. BioDoser uses least squares and loop testing of monotonicity method and algorithm of non-uniformed confidence interval. In addition, this program enables integration of multiple different biomarkers typically used in biological dosimetry. These include partial body exposure, minimum number of cells to be analyzed, G function correction modules that are helpful in dose estimation when using chromosome aberration frequencies, micronucleus rate, comet assay and other biological methods. The software is freely available at http://bit.ly/kKBSNR.

Hong Wang; Qiang Liu; Dandan Wan; Jian Xiang; Liqing Du; Yan Wang; Jia Cao; Yue Fu; Feiyue Fan; Markus Hecker

2012-01-01T23:59:59.000Z

314

Modular Systems Biology applied to TGFbeta and DNA Damage Response Signaling following Low Dose Radiation  

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

Modular Systems Biology applied to TGFbeta and DNA Damage Response Signaling following Modular Systems Biology applied to TGFbeta and DNA Damage Response Signaling following Low Dose Radiation Francis A. Cucinotta 1 , Yongfeng Li 2 , Minli Wang 2 , Claudio Carra 2 , Janice Pluth 3 , and Peter O'Neill 4 1 NASA Johnson Space Center, Houston, TX 2 U.S.R.A. Division of Life Sciences, Houston TX 3 Lawrence Berkeley National Laboratory, Berkeley CA 4 Oxford University, Oxford UK Abstract: Modular systems biology (MSB) describes the complexity of biological systems using well defined modules that represent distinct biological response pathways or sub-systems within pathways. We review mathematical concepts from control theory that can be used to identify and construct well defined modules for describing complex biological processes. The DNA damage response and TGFbeta/Smad signaling are two important response pathways following

315

New dose-mortality data based on 3-D radiation shielding calculation for concrete buildings at Nagasaki  

SciTech Connect

The analysis of radiation doses received during the World War II attack on Nagasaki provides an important source of biochemical information. More than 40 years after the war, it has been possible to make a satisfactory calculation of the doses to personnel inside reinforced concrete buildings by use of a 3-dimensional discrete ordinates code, TORT. The results were used to deduce a new value of the LD50 parameter that is in good agreement with traditional values. The new discrete ordinates software appears to have potential application to conventional radiation transport calculations as well. 9 refs., 3 figs., 2 tabs.

Rhoades, W.A.; Childs, R.L.; Ingersoll, D.T.

1988-01-01T23:59:59.000Z

316

Determining the effective dose equivalent and effective dose for anthropomorphic phantoms with different torso thicknesses for broad parallel beams of external photon radiation  

E-Print Network (OSTI)

or ans is defined b ol ons. 11 2. 3 Oak Ridge Phantom Used in This Study The anthropomorphic phantom used in this study is a hermaphroditic model developed at Oak Ridge National Laboratory (ORNL) and described by Eckerman et al. (1996). It represents...

Chichkov, Igor

1999-01-01T23:59:59.000Z

317

Establishing cytogenetic biodosimetry laboratory in Saudi Arabia and producing preliminary calibration curve of dicentric chromosomes as biomarker for medical dose estimation in response to radiation emergencies  

Science Journals Connector (OSTI)

In cases of individual radiation overexposure, it is important to provide suitable dose assessment, medical triage, diagnoses and treatment ... for effective medical management of a suspected acute radiation over...

Khaled Al-Hadyan; Sara Elewisy; Belal Moftah; Mohamed Shoukri; Awad Alzahrany

2014-04-01T23:59:59.000Z

318

A study on leakage radiation dose at ELV-4 electron accelerator bunker  

Science Journals Connector (OSTI)

Shielding is an important aspect in the safety of an accelerator and the most important aspects of a bunker shielding is the door. The bunkers door should be designed properly to minimize the leakage radiation and shall not exceed the permitted limit of 2.5?Sv/hr. In determining the leakage radiation dose that passed through the door and gaps between the door and the wall 2-dimensional manual calculations are often used. This method is hard to perform because visual 2-dimensional is limited and is also very difficult in the real situation. Therefore estimation values are normally performed. In doing so the construction cost would be higher because of overestimate or underestimate which require costly modification to the bunker. Therefore in this study two methods are introduced to overcome the problem such as simulation using MCNPX Version 2.6.0 software and manual calculation using 3-dimensional model from Autodesk Inventor 2010 software. The values from the two methods were eventually compared to the real values from direct measurements using Ludlum Model 3 with Model 44-9 probe survey meter.

2014-01-01T23:59:59.000Z

319

DOE-STD-1153-2002; A Graded Approach for Evaluating Radiation Doses to Aquatic and Terrestrial Biota  

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

M3-19 M3-19 3 Equations and Models for Calculating Dose to Biota and Deriving BCGs Based on the potential pathways of exposure, BCGs were derived for surface water, sediment, and soil. Calculated using conservative assumptions, the BCGs are intended to preclude the relevant biota from being exposed to radiation levels in excess of established or recommended biota dose limits. Determination of compliance with the dose limits requires that all organism- relevant environmental media be evaluated at the same time. This is done by using the "sum of fractions" approach commonly used in evaluating radionuclide discharges to the environment. 3.1 An Important Note on Estimating Internal Tissue Concentrations for Use in Dose Equations: The Lumped Parameter For most radionuclides, the single most important predictor of biota dose is the method used to estimate internal tissue concentrations.

320

The cytokinesis-blocked micronucleus assay: Dose estimation and inter-individual differences in the response to ?-radiation  

Science Journals Connector (OSTI)

Abstract Biological dosimetry plays an important role in case of a radiation accident or incident, either when it is the only way to estimate the dose or when it is used to complement physical dosimetry. A cytogenetic study was conducted in a group of 16 Portuguese individuals by use of the cytokinesis-blocked micronucleus (CBMN) assay. A doseresponse curve for micronuclei yield was established with a linear-quadratic model: Y=(0.01220.0010)+(0.02410.0023)D+(0.01930.0007)D2. Also, baseline values for the micronucleus formation in the 16 donors were analyzed, with results in close agreement with those from other laboratories. A validation experiment was carried out with three individuals. The real and the estimated doses obtained with the doseresponse curve were in very good agreement, allowing the use of the micronucleus doseresponse calibration curve in biological dosimetry for estimation of radiation dose in case of overexposure. The results obtained for the cytogenetic endpoints, studied in the same group of 16 individuals, were also analyzed as a function of age and gender. A higher inter-variability was observed for the higher dose points and differences in response were identified between genders, above 2Gy, for all endpoints.

A.C. Antunes; V. Martins; J. Cardoso; L. Santos; O. Monteiro Gil

2014-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "radiation dose equivalent" 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

Estimation of the biological dose received by five victims of a radiation accident using three different cytogenetic tools  

Science Journals Connector (OSTI)

The present study aims to estimate the biological doses received by five victims (A, B, C, D and E) of the Shanxi Taiyuan radiation accident in China of 2008 and to investigate the value of the cytokinesis-block micronuclei (CBMN) and premature chromosome condensation (PCC) assays in the estimation of biological doses received by the victims of a radiation accident. Conventional chromosome aberration analysis and the CBMN assay, as well as a drug-induced PCC assay recently established by our group, were performed on peripheral blood and bone marrow samples from five victims after the accident. The biological doses were estimated by scoring dicentrics plus centric rings, micronuclei and PCC rings. A high doseeffect curve and the nuclear division index (NDI) we previously established were used to estimate the dose received by victim A, the most highly affected victim of the five. The doses for the five victims (A, B, C, D and E) were 12.4, 3.4, 2.5, 2.1 and 2.2Gy, respectively, estimated by scoring dicentrics plus rings in peripheral blood lymphocytes. Similar results were obtained by combining the CBMN and NDI (CBMN+NDI) assays and the PCC assay. The doses estimated by the three methods were in accordance with the clinical symptoms observed. The specific dicentric assay with a low background level may be a better indicator for biological dose evaluation than the CBMN and PCC assays. The high dose curve we established is reliable and could become a suitable supplement to traditional biodosimetry for dose estimation. The CBMN and drug-induced PCC assays are simple, rapid and accurate. The two methods reinforce and verify the results observed with chromosome aberration analysis.

Bo Yao; Yufang Li; Guangxian Liu; Mei Guo; Juan Bai; Qiuhong Man; Lijuan Qiu; Huisheng Ai

2013-01-01T23:59:59.000Z

322

Electron Paramagnetic Resonance Oxygen Image Hypoxic Fraction Plus Radiation Dose Strongly Correlates With Tumor Cure in FSa Fibrosarcomas  

SciTech Connect

Purpose: Tumor hypoxia has long been known to produce resistance to radiation. In this study, electron paramagnetic resonance (EPR) oxygen imaging was investigated for its power to predict the success of tumor control according to tumor oxygenation level and radiation dose. Methods and Materials: A total of 34 EPR oxygen images were obtained from the legs of C3H mice bearing 0.5-cm{sup 3} FSa fibrosarcomas under both normal (air breathing) and clamped tumor conditions. Under the same conditions as those during which the images were obtained, the tumors were irradiated to a variety of doses near the FSa dose at which 50% of tumors were cured. Tumor tissue was distinguished from normal tissue using co-registration of the EPR oxygen images with spin-echo magnetic resonance imaging of the tumor and/or stereotactic localization. The tumor voxel statistics in the EPR oxygen image included the mean and median partial pressure of oxygen and the fraction of tumor voxels below the specified partial pressure of oxygen values of 3, 6, and 10 mm Hg. Bivariate logistic regression analysis using the radiation dose and each of the EPR oxygen image statistics to determine which best separated treatment failure from success. Results: The measurements of the dose at which 50% of tumors were cured were similar to those found in published data for this syngeneic tumor. Bivariate analysis of 34 tumors demonstrated that tumor cure correlated with dose (p = 0.004) and with a <10 mm Hg hypoxic fraction (p = 0.023). Conclusion: Our results have shown that, together, radiation dose and EPR image hypoxic fraction separate the population of FSa fibrosarcomas that are cured from those that fail, thus predicting curability.

Elas, Martyna [Department of Radiation and Cellular Oncology, University of Chicago Pritzker School of Medicine, Chicago, IL (United States); Center for Electron Paramagnetic Resonance Imaging In Vivo Physiology, University of Chicago, Chicago, IL (United States); Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Krakow (Poland); Bell, Rebecca; Hleihel, Danielle; Barth, Eugene D.; McFaul, Colin [Department of Radiation and Cellular Oncology, University of Chicago Pritzker School of Medicine, Chicago, IL (United States); Center for Electron Paramagnetic Resonance Imaging In Vivo Physiology, University of Chicago, Chicago, IL (United States); Haney, Chad R. [Department of Radiation and Cellular Oncology, University of Chicago Pritzker School of Medicine, Chicago, IL (United States); Center for Electron Paramagnetic Resonance Imaging In Vivo Physiology, University of Chicago, Chicago, IL (United States); Department of Radiology, University of Chicago Pritzker School of Medicine, Chicago, IL (United States); Bielanska, Joanna; Pustelny, Katarzyna [Department of Radiation and Cellular Oncology, University of Chicago Pritzker School of Medicine, Chicago, IL (United States); Center for Electron Paramagnetic Resonance Imaging In Vivo Physiology, University of Chicago, Chicago, IL (United States); Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Krakow (Poland); Ahn, Kang-Hyun [Department of Radiation and Cellular Oncology, University of Chicago Pritzker School of Medicine, Chicago, IL (United States); Center for Electron Paramagnetic Resonance Imaging In Vivo Physiology, University of Chicago, Chicago, IL (United States)] (and others)

2008-06-01T23:59:59.000Z

323

Assessment of the occupational radiation exposure doses to workers at INMOL Pakistan (200711)  

Science Journals Connector (OSTI)

......measures and safety of workers during...been sent to the Radiation Dosimetry Laboratory...fabricated computer software . The calibration...PNRA and IAEA radiation protection and safety guidelines...radiation and for the safety of radiation sources. (1994......

Khalid Masood; Junaid Zafar; Tasneem Zafar; Haroon Zafar

2013-06-01T23:59:59.000Z

324

The Estimation of Molecular and Cytogenetic Effects in Mice Exposed to Chronic Low Dose-Rate Gamma-Radiation  

Science Journals Connector (OSTI)

Molecular and cytogenetic parameters were estimated in male CBA/lac mice exposed to chronic low dose-rate ?-radiation (62 cGy/year) for 40, 80, 120, 210, and 365 days. After 40 days of exposure (6.7 cGy), sple...

A. N. Osipov; A. L. Elakov; P. V. Puchkov

2002-10-01T23:59:59.000Z

325

Evaluation of radiation doses and associated risk from the Fukushima nuclear accident to marine biota and human consumers of seafood  

Science Journals Connector (OSTI)

...to marine biota and human consumers of seafood 10.1073/pnas.1221834110 Nicholas...radionuclides are in human food items such as seafood. Although statements were released by...or for human consumers of contaminated seafood. We have therefore calculated the radiation doses absorbed by diverse marine...

Nicholas S. Fisher; Karine Beaugelin-Seiller; Thomas G. Hinton; Zofia Baumann; Daniel J. Madigan; Jacqueline Garnier-Laplace

2013-01-01T23:59:59.000Z

326

Quantifying murine bone marrow and blood radiation dose response following 18F-FDG PET with DNA damage biomarkers  

Science Journals Connector (OSTI)

Abstract The purpose of this study was to quantify the poorly understood radiation doses to murine bone marrow and blood from whole-body fluorine 18 (18F)-fluorodeoxyglucose (FDG) positron emission tomography (PET), by using specific biomarkers and comparing with whole body external low dose exposures. Groups of 35 mice were randomly assigned to 10 groups, each receiving either a different activity of 18F-FDG: 037MBq or whole body irradiated with corresponding doses of 0300mGy X-rays. Blood samples were collected at 24h and at 43h for reticulocyte micronucleus assays and QPCR analysis of gene expression in peripheral blood leukocytes. Blood and bone marrow dose estimates were calculated from injected activities of 18F-FDG and were based on a recommended ICRP model. Doses to the bone marrow corresponding to 33.43mGy and above for internal 18F-FDG exposure and to 25mGy and above for external X-ray exposure, showed significant increases in radiation-induced MN-RET formation relative to controls (Pdoseresponses at 24h for Bbc3 and Cdkn1 were similar for 18F-FDG and X-ray exposures, with significant modifications occurring for doses over 300mGy for Bbc3 and at the lower dose of 150mGy for Cdkn1a. Both leucocyte gene expression and quantification of MN-RET are highly sensitive biomarkers for reliable estimation of the low doses delivered in vivo to, respectively, blood and bone marrow, following 18F-FDG PET.

Grainne Manning; Kristina Taylor; Paul Finnon; Jennifer A. Lemon; Douglas R. Boreham; Christophe Badie

2014-01-01T23:59:59.000Z

327

Implementation of dose management system at radiation protection board of Ghana Atomic Energy Commission  

Science Journals Connector (OSTI)

......12-20. 7 Occupational Radiation Protection. Radiation Protection and Safety Guide. (2002) GRPB-G3...International Commission on Radiation Units and Measurements...system (DMS) is a computer software developed by the International......

F. Hasford; J. K. Amoako; E. O. Darko; G. Emi-Reynolds; E. K. Sosu; F. Otoo; G. O. Asiedu

2012-01-01T23:59:59.000Z

328

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

SciTech Connect

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

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

2012-10-01T23:59:59.000Z

329

The bovine tuberculosis burden in cattle herds in zones with low dose radiation pollution in the Ukraine  

SciTech Connect

The authors describe a study of the tuberculosis (TB) incidence in cattle exposed to low doses of radiation resulting from the Chernobyl (pronounced Chornobyl in Ukrainian) nuclear plant catastrophe in 1986. The purpose of the study was to determine if ionising radiation influences the number of outbreaks of bovine TB and their severity on farms in the Kyiv, Cherkasy and Chernigiv regions of the Ukraine. These farms are all located within a 200 km radius of Chernobyl and have had low?dose radiation pollution. Pathological and blood samples were taken from cattle in those regions that had positive TB skin tests. Mycobacterium spp. were isolated, differentiated by PCR, analysed and tested in guinea?pigs and rabbits. Species differentiation showed a significant percentage of atypical mycobacteria, which resulted in the allergic reactions to tuberculin antigen in the skin test. Mixed infection of M. bovis and M. avium subsp. hominissuis was found in three cases. The results concluded that low?dose radiation plays a major role in the occurrence of bovine TB in regions affected by the Chernobyl nuclear disaster.

Weller, Richard E.; Skrypnyk, Artem; Zavgorodniy, Andriy; Stegniy, Borys; Gerilovych, Anton; Kutsan, Oleksandr; Pozmogova, Svitlana; Sapko, Svitlana

2009-02-01T23:59:59.000Z

330

Adaptive Liver Stereotactic Body Radiation Therapy: Automated Daily Plan Reoptimization Prevents Dose Delivery Degradation Caused by Anatomy Deformations  

SciTech Connect

Purpose: To investigate how dose distributions for liver stereotactic body radiation therapy (SBRT) can be improved by using automated, daily plan reoptimization to account for anatomy deformations, compared with setup corrections only. Methods and Materials: For 12 tumors, 3 strategies for dose delivery were simulated. In the first strategy, computed tomography scans made before each treatment fraction were used only for patient repositioning before dose delivery for correction of detected tumor setup errors. In adaptive second and third strategies, in addition to the isocenter shift, intensity modulated radiation therapy beam profiles were reoptimized or both intensity profiles and beam orientations were reoptimized, respectively. All optimizations were performed with a recently published algorithm for automated, multicriteria optimization of both beam profiles and beam angles. Results: In 6 of 12 cases, violations of organs at risk (ie, heart, stomach, kidney) constraints of 1 to 6 Gy in single fractions occurred in cases of tumor repositioning only. By using the adaptive strategies, these could be avoided (<1 Gy). For 1 case, this needed adaptation by slightly underdosing the planning target volume. For 2 cases with restricted tumor dose in the planning phase to avoid organ-at-risk constraint violations, fraction doses could be increased by 1 and 2 Gy because of more favorable anatomy. Daily reoptimization of both beam profiles and beam angles (third strategy) performed slightly better than reoptimization of profiles only, but the latter required only a few minutes of computation time, whereas full reoptimization took several hours. Conclusions: This simulation study demonstrated that replanning based on daily acquired computed tomography scans can improve liver stereotactic body radiation therapy dose delivery.

Leinders, Suzanne M. [Erasmus Medical Center-Daniel den Hoed Cancer Center, Rotterdam (Netherlands); Delft University of Technology, Delft (Netherlands); Breedveld, Sebastiaan; Mndez Romero, Alejandra [Erasmus Medical Center-Daniel den Hoed Cancer Center, Rotterdam (Netherlands); Schaart, Dennis [Delft University of Technology, Delft (Netherlands); Seppenwoolde, Yvette, E-mail: y.seppenwoolde@erasmusmc.nl [Erasmus Medical Center-Daniel den Hoed Cancer Center, Rotterdam (Netherlands); Heijmen, Ben J.M. [Erasmus Medical Center-Daniel den Hoed Cancer Center, Rotterdam (Netherlands)

2013-12-01T23:59:59.000Z

331

Threshold estimation from the linear dose-response model: Method and radiation data  

Science Journals Connector (OSTI)

The linear dose-response model is considered a conservative, nonthreshold relationship. This is based on a confusion between the sufficient condition (that is, zero slope at zero dose) and the necessary condit...

David J. Schaeffer; Konanur G. Janardan; Harold W. Kerster

1981-01-01T23:59:59.000Z

332

Radioactivity of 210Pb in Japanese cigarettes and radiation dose from smoking inhalation  

Science Journals Connector (OSTI)

......Center, Japan Atomic Energy Agency, 1550 Kamisaibara...cigarettes a day. The average doses from 210Pb...nine samples were home-grown tobaccos...N is the daily consumption of cigarettes...respectively. The average effective doses were...cigarettes a day. The average doses from (210......

A. Sakoda; K. Fukao; A. Kawabe; T. Kataoka; K. Hanamoto; K. Yamaoka

2012-06-01T23:59:59.000Z

333

Construction of dose response calibration curves for dicentrics and micronuclei for X radiation in a Serbian population  

Science Journals Connector (OSTI)

Abstract Biological dosimetry using chromosome damage biomarkers is a valuable dose assessment method in cases of radiation overexposure with or without physical dosimetry data. In order to estimate dose by biodosimetry, any biological dosimetry service have to have its own dose response calibration curve. This paper reveals the results obtained after irradiation of blood samples from fourteen healthy male and female volunteers in order to establish biodosimetry in Serbia and produce dose response calibration curves for dicentrics and micronuclei. Taking into account pooled data from all the donors, the resultant fitted curve for dicentrics is: Ydic=0.0009 (0.0003)+0.0421 (0.0042)נD+0.0602 (0.0022)נD2; and for micronuclei: Ymn=0.0104 (0.0015)+0.0824 (0.0050)נD+0.0189 (0.0017)נD2. Following establishment of the dose response curve, a validation experiment was carried out with four blood samples. Applied and estimated doses were in good agreement. On this basis, the results reported here give us confidence to apply both calibration curves for future biological dosimetry requirements in Serbia.

J. Pajic; B. Rakic; D. Jovicic; A. Milovanovic

2014-01-01T23:59:59.000Z

334

Radiosurgery for Para-IAC Meningiomas: The Effect of Radiation Dose to the Cochlea on Hearing Outcome  

SciTech Connect

Purpose: This study was performed to assess the radiosurgical results of meningiomas extending into the internal acoustic canal (para-IAC meningiomas), with a particular focus on the effect of radiation dose to the cochlea on hearing outcome. Methods and Materials: A total of 50 patients who underwent radiosurgery for para-IAC meningiomas between 1998 and 2009, which were followed for 2 years, were enrolled. The mean age was 55.8 years (range, 15-75). The mean tumor volume was 6.1 cm{sup 3} (range, 1.0-19.0), the mean tumor length in the IAC was 6.9 mm (range, 1.3-13.3), and the mean prescribed marginal dose was 13.1 Gy (range, 10-15) at an isodose line of 50%. The mean follow-up duration was 46 months (range, 24-122). Results: Eight (16.0%) patients had nonserviceable hearing at the time of surgery. At the last follow-up, the tumor control rate was 94%; unchanged in 17 patients, decreased in 30 patients, and increased in 3 patients. Among 42 patients with serviceable hearing at the time of radiosurgery, it was preserved in 41 (97.6%) patients at the last follow-up. The maximal and mean radiation doses to the cochleae of these 41 patients were 5.8 Gy {+-} 0.3 (range, 3.1-11.5) and 4.3 Gy {+-} 0.2 (range, 2.2-7.5), respectively. The maximal dose to the cochlea of the patient who lost hearing after radiosurgery was 4.7 Gy. Conclusions: The radiation dose to the cochlea may have the minimal toxic effect on the hearing outcome in patients who undergo radiosurgery for para-IAC meningiomas.

Kim, Young-Hoon [Department of Neurosurgery, Seoul National University Bundang Hospital, Seongnam-si (Korea, Republic of) [Department of Neurosurgery, Seoul National University Bundang Hospital, Seongnam-si (Korea, Republic of); Department of Neurosurgery, Seoul National University College of Medicine, Seoul (Korea, Republic of); Kim, Dong Gyu, E-mail: gknife@plaza.snu.ac.kr [Department of Neurosurgery, Seoul National University Hospital, Seoul (Korea, Republic of); Department of Neurosurgery, Seoul National University College of Medicine, Seoul (Korea, Republic of); Han, Jung Ho [Department of Neurosurgery, Seoul National University Bundang Hospital, Seongnam-si (Korea, Republic of) [Department of Neurosurgery, Seoul National University Bundang Hospital, Seongnam-si (Korea, Republic of); Department of Neurosurgery, Seoul National University College of Medicine, Seoul (Korea, Republic of); Chung, Hyun-Tai; Kim, In Kyung; Song, Sang Woo [Department of Neurosurgery, Seoul National University Hospital, Seoul (Korea, Republic of) [Department of Neurosurgery, Seoul National University Hospital, Seoul (Korea, Republic of); Department of Neurosurgery, Seoul National University College of Medicine, Seoul (Korea, Republic of); Park, Jeong-Hoon [Department of Neurosurgery, Seoul National University Bundang Hospital, Seongnam-si (Korea, Republic of) [Department of Neurosurgery, Seoul National University Bundang Hospital, Seongnam-si (Korea, Republic of); Department of Neurosurgery, Seoul National University College of Medicine, Seoul (Korea, Republic of); Kim, Jin Wook; Kim, Yong Hwy; Park, Chul-Kee [Department of Neurosurgery, Seoul National University Hospital, Seoul (Korea, Republic of) [Department of Neurosurgery, Seoul National University Hospital, Seoul (Korea, Republic of); Department of Neurosurgery, Seoul National University College of Medicine, Seoul (Korea, Republic of); Kim, Chae-Yong [Department of Neurosurgery, Seoul National University Bundang Hospital, Seongnam-si (Korea, Republic of) [Department of Neurosurgery, Seoul National University Bundang Hospital, Seongnam-si (Korea, Republic of); Department of Neurosurgery, Seoul National University College of Medicine, Seoul (Korea, Republic of); Paek, Sun Ha; Jung, Hee-Won [Department of Neurosurgery, Seoul National University Hospital, Seoul (Korea, Republic of) [Department of Neurosurgery, Seoul National University Hospital, Seoul (Korea, Republic of); Department of Neurosurgery, Seoul National University College of Medicine, Seoul (Korea, Republic of)

2012-11-01T23:59:59.000Z

335

Estimation of tumour dose enhancement due to gold nanoparticles during typical radiation treatments: a preliminary Monte Carlo study  

Science Journals Connector (OSTI)

A recent mice study demonstrated that gold nanoparticles could be safely administered and used to enhance the tumour dose during radiation therapy. The use of gold nanoparticles seems more promising than earlier methods because of the high atomic number of gold and because nanoparticles can more easily penetrate the tumour vasculature. However, to date, possible dose enhancement due to the use of gold nanoparticles has not been well quantified, especially for common radiation treatment situations. Therefore, the current preliminary study estimated this dose enhancement by Monte Carlo calculations for several phantom test cases representing radiation treatments with the following modalities: 140 kVp x-rays, 4 and 6 MV photon beams, and 192Ir gamma rays. The current study considered three levels of gold concentration within the tumour, two of which are based on the aforementioned mice study, and assumed either no gold or a single gold concentration level outside the tumour. The dose enhancement over the tumour volume considered for the 140 kVp x-ray case can be at least a factor of 2 at an achievable gold concentration of 7 mg Au/g tumour assuming no gold outside the tumour. The tumour dose enhancement for the cases involving the 4 and 6 MV photon beams based on the same assumption ranged from about 1% to 7%, depending on the amount of gold within the tumour and photon beam qualities. For the 192Ir cases, the dose enhancement within the tumour region ranged from 5% to 31%, depending on radial distance and gold concentration level within the tumour. For the 7 mg Au/g tumour cases, the loading of gold into surrounding normal tissue at 2 mg Au/g resulted in an increase in the normal tissue dose, up to 30%, negligible, and about 2% for the 140 kVp x-rays, 6 MV photon beam, and 192Ir gamma rays, respectively, while the magnitude of dose enhancement within the tumour was essentially unchanged.

Sang Hyun Cho

2005-01-01T23:59:59.000Z

336

Internal Dose Estimates from  

E-Print Network (OSTI)

Appendix F Internal Dose Estimates from NTS Fallout F-1 #12;Radiation Dose to the Population;TABLE OF CONTENTS Page F- Part I. Estimates of Dose...........................................................................................40 Comparison to dose estimates from global fallout

337

Radiation Dose Is More Than A Number Workshop 15-16 September 2011  

E-Print Network (OSTI)

or Water Contamination Nuclear detonation Accident ­ Power Plant Release ­ Sealed radiological sources.D. Associate Director, Radiation/Nuclear Countermeasures Program Division of Allergy, Immunology #12;NIAID Radiation/Nuclear Medical Countermeasures Development Program HHS assigned NIH

338

Central dose data management and analysis in IT-driven radiation protection strategies  

Science Journals Connector (OSTI)

......at the very heart of the provision of radiation safety services or, alternatively, placing radiation safety management at the heart of radiological practice. MATERIALS AND METHODS Software development During the summer of 1993......

M. Ward; D. Hughes; P. Connolly; B. M. Moores

2005-05-01T23:59:59.000Z

339

DOE-STD-1153-2002; A Graded Approach for Evaluating Radiation Doses to Aquatic and Terrestrial Biota  

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

1 1 PRINCIPLES AND APPLICATION MODULE 1: PRINCIPLES AND APPLICATION DOE-STD-1153-2002 INTENTIONALLY BLANK DOE-STD-1153-2002 M1-1 1 Introduction The U.S. Department of Energy (DOE) is accountable to Congress and the public for the safe conduct of its activities, including facility operation, waste management and disposal activities, and remediation of environmental contamination. These routine activities may result in releases of radionuclides to the air and water, accumulation of radionuclides in soil and sediment, and the potential for plants, animals, and members of the public to be exposed to radiation. DOE Order 5400.5, "Radiation Protection of the Public and the Environment" (1990a), lists the environmental radiation protection requirements that DOE and DOE- contractor employees must meet to protect aquatic animals. In addition, dose limits below

340

Cumulative radiation dose estimates from medical imaging in paediatric patients with non-oncologic chronic illnesses. A systematic review  

Science Journals Connector (OSTI)

Abstract Paediatric patients with non-oncologic chronic illnesses often require ongoing care that may result in repeated imaging and exposure to ionizing radiation from both diagnostic and interventional procedures. In this study the scientific literature on cumulative effective dose (CED) of radiation accrued from medical imaging among specific cohorts of paediatric, non-oncologic chronic patients (inflammatory bowel disease, cystic fibrosis, congenital heart disease, shunt-treated hydrocephalus, hemophilia, spinal dysraphism) was systematically reviewed. We conducted PubMed/Medline, Scopus and EMBASE searches of peer-reviewed papers on CED from diagnostic and therapeutic radiological examinations. No time restriction was introduced in the search. Only studies reporting \\{CEDs\\} accrued for a period >1 year were included. We found that the annual CED was relatively low (320mSv/year) in Crohn's patients. This extra yearly radiation exposure accrues over the lifetime and can reach high values (>100mSv) in selected cohorts of paediatric chronic patients.

Marco Brambilla; Andreana De Mauri; Domenico Lizio; Lucia Leva; Alessandro Carriero; Clara Carpeggiani; Eugenio Picano

2014-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "radiation dose equivalent" 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

The similar effects of low-dose ionizing radiation and non-ionizing radiation from background environmental levels of exposure  

Science Journals Connector (OSTI)

The meltdown and release of radioactivity (ionizing radiation) from four damaged nuclear reactors at the Fukushima Nuclear Facility in Japan in March 2011 continues to contaminate air and ocean water even 1year ...

Cindy Sage

2012-06-01T23:59:59.000Z

342

Patient radiation doses in interventional cardiology in the U.S.: Advisory data sets and possible initial values for U.S. reference levels  

SciTech Connect

Purpose: To determine patient radiation doses from interventional cardiology procedures in the U.S and to suggest possible initial values for U.S. benchmarks for patient radiation dose from selected interventional cardiology procedures [fluoroscopically guided diagnostic cardiac catheterization and percutaneous coronary intervention (PCI)]. Methods: Patient radiation dose metrics were derived from analysis of data from the 2008 to 2009 Nationwide Evaluation of X-ray Trends (NEXT) survey of cardiac catheterization. This analysis used deidentified data and did not require review by an IRB. Data from 171 facilities in 30 states were analyzed. The distributions (percentiles) of radiation dose metrics were determined for diagnostic cardiac catheterizations, PCI, and combined diagnostic and PCI procedures. Confidence intervals for these dose distributions were determined using bootstrap resampling. Results: Percentile distributions (advisory data sets) and possible preliminary U.S. reference levels (based on the 75th percentile of the dose distributions) are provided for cumulative air kerma at the reference point (K{sub a,r}), cumulative air kerma-area product (P{sub KA}), fluoroscopy time, and number of cine runs. Dose distributions are sufficiently detailed to permit dose audits as described in National Council on Radiation Protection and Measurements Report No. 168. Fluoroscopy times are consistent with those observed in European studies, but P{sub KA} is higher in the U.S. Conclusions: Sufficient data exist to suggest possible initial benchmarks for patient radiation dose for certain interventional cardiology procedures in the U.S. Our data suggest that patient radiation dose in these procedures is not optimized in U.S. practice.

Miller, Donald L.; Hilohi, C. Michael; Spelic, David C. [Center for Devices and Radiological Health, Food and Drug Administration, 10903 New Hampshire Avenue, Silver Spring, Maryland 20993 (United States)

2012-10-15T23:59:59.000Z

343

How air influences radiation dose deposition in multiwell culture plates: a Monte Carlo simulation of radiation geometry  

Science Journals Connector (OSTI)

......that this underdosage does not have a significant...related to a lack of electronic equilibrium. This is...Fig. 5b). MC calculations of the same plate geometry...Oncology Physics: A Handbook for Teachers and Students-Podgorsak...Comparison of dose calculation algorithms in slab phantoms......

Sebastia Sabater; Roberto Berenguer; Paloma Honrubia-Gomez; Miguel Rivera; Ana Nuez; Esther Jimenez-Jimenez; Ana Martos; Carmen Ramirez-Castillejo

2014-09-01T23:59:59.000Z

344

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

SciTech Connect

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

345

Estimation of radiation doses to patients and surgeons from various fluoroscopically guided orthopaedic surgeries  

Science Journals Connector (OSTI)

......the medical personnel exposure...the medical personnel is always...to the operating surgeon and...potential selections. At 80 kVp...level of training and experience of the operating surgeon...patient and personnel doses. Using......

Ioannis A. Tsalafoutas; Virginia Tsapaki; Alkiviadis Kaliakmanis; Spiridon Pneumaticos; Fotis Tsoronis; Elias D. Koulentianos; George Papachristou

2008-01-01T23:59:59.000Z

346

Occupational dose reduction at nuclear power plants: Annotated bibliography of selected readings in radiation protection and ALARA. Volume 7  

SciTech Connect

The ALARA Center at Brookhaven National Laboratory publishes a series of bibliographies of selected readings in radiation protection and ALARA in the continuing effort to collect and disseminate information on radiation dose reduction at nuclear power plants. This is volume 7 of the series. The abstracts in this bibliography were selected from proceedings of technical meetings and conferences, journals, research reports, and searches of the Energy Science and Technology database of the US Department of Energy. The subject material of these abstracts relates to radiation protection and dose reduction, and ranges from use of robotics to operational health physics, to water chemistry. Material on the design, planning, and management of nuclear power stations is included, as well as information on decommissioning and safe storage efforts. Volume 7 contains 293 abstract, an author index, and a subject index. The author index is specific for this volume. The subject index is cumulative and lists all abstract numbers from volumes 1 to 7. The numbers in boldface indicate the abstracts in this volume; the numbers not in boldface represent abstracts in previous volumes.

Kaurin, D.G.; Khan, T.A.; Sullivan, S.G.; Baum, J.W. [Brookhaven National Lab., Upton, NY (United States)

1993-07-01T23:59:59.000Z

347

Occupational dose reduction at nuclear power plants: Annotated bibliography of selected readings in radiation protection and ALARA. Volume 8  

SciTech Connect

The ALARA Center at Brookhaven National Laboratory publishes a series of bibliographies of selected readings in radiation protection and ALARA in a continuing effort to collect and disseminate information on radiation dose reduction at nuclear power plants. This volume 8 of the series. The abstracts in this bibliography were selected form proceedings of technical meetings and conference journals, research reports, and searches of the Energy Science and Technology database of the US Department of Energy. The subject material of these abstracts relates to the many aspects of radiation protection and dose reduction, and ranges form use of robotics, to operational health physics, to water chemistry. Material on the design, planning, and management of nuclear power stations is included, as well as information on decommissioning and safe storage efforts. Volume 8 contains 232 abstracts, an author index, and a subject index. The author index is specific for this volume. The subject index is cumulative and lists all abstract numbers from volumes 1 to 8. The numbers in boldface indicate the abstracts in this volume; the numbers not in boldface represent abstracts in previous volumes.

Sullivan, S.G.; Khan, T.A.; Xie, J.W. [Brookhaven National Lab., Upton, NY (United States)

1995-05-01T23:59:59.000Z

348

On the use of computed radiography plates for quality assurance of intensity modulated radiation therapy dose distributions  

SciTech Connect

Purpose: As traditional film is phased out in most radiotherapy centers, computed radiography (CR) systems are increasingly being purchased as a replacement. CR plates can be used for patient imaging, but may also be used for a variety of quality assurance (QA) purposes and can be calibrated in terms of dose. This study looks at their suitability for verification of intensity modulated radiation therapy (IMRT) dose distributions. Methods: A CR plate was calibrated in terms of the relative dose and the stability of response over 1 year was studied. The effect of exposing the CR plate to ambient light and of using different time delays before scanning was quantified. The CR plate was used to verify the relative dose distributions for ten IMRT patients and the results were compared to those obtained using a two dimensional (2D) diode array. Results: Exposing the CR plate to 10 s of ambient light between irradiation (174 cGy) and scanning erased approximately 80% of the signal. Changes in delay time between irradiation and scanning also affected the measurement results. The signal on the plate was found to decay at a rate of approximately 3.6 cGy/min in the first 10 min after irradiation. The use of a CR plate for IMRT patient-specific QA resulted in a significantly lower distance to agreement (DTA) and gamma pass rate than when using a 2D diode array for the measurement. This was primarily due to the over-response of the CR phosphor to low energy scattered radiation. For the IMRT QA using the CR plate, the average gamma pass rate was 97.3%. For the same IMRT QA using a diode array, the average gamma pass rate was 99.7%. The gamma criteria used were 4% dose difference and 4 mm DTA for head and neck treatments and 3% dose difference and 3 mm DTA for prostate treatments. The gamma index tolerance was 1. The lowest 10% of the dose distribution was excluded from all gamma and DTA analyses. Conclusions: Although the authors showed that CR plates can be used for patient specific IMRT QA, the practical problems such as the over-response to low energy scatter and signal fading with light exposure and time mean that alternative detectors such as radiochromic film or diode arrays will be a more sensible choice for most radiotherapy departments.

Day, R. A.; Sankar, A. P.; Nailon, W. H.; MacLeod, A. S. [Department of Oncology Physics, Edinburgh Cancer Centre, Western General Hospital, Crewe Road South, Edinburgh EH4 2XU (United Kingdom)

2011-02-15T23:59:59.000Z

349

A Dose-Volume Analysis of Radiation Pneumonitis in Non-Small Cell Lung Cancer Patients Treated With Stereotactic Body Radiation Therapy  

SciTech Connect

Purpose: To examine the rates and risk factors of radiation pneumonitis (RP) in non-small cell lung cancer (NSCLC) patients treated with stereotactic body radiotherapy (SBRT). Methods and Materials: Dosimetry records for 251 patients with lymph node-negative Stage I-IIB NSCLC and no prior chest radiation therapy (RT) treated with SBRT were reviewed. Patients were coded on the basis of the presence of at least Grade (G) 2 RP using the Common Toxicity Criteria version 2 criteria. Radiation doses, V5, V10, V20, and mean lung dose (MLD) data points were extracted from the dose-volume histogram (DVH). Results: Median PTV volume was 48 cc. Median prescribed radiation dose was 60 Gy delivered in three fractions to the 80% isodose line. Median age at treatment was 74 years. Median follow-up was 17 months. RP was reported after treatment of 42 lesions: G1 in 19 (8%), G2 in 17 (7%), G3 in 5 (2%), and G4 in 1 (0.4%). Total lung DVHs were available for 143 patients. For evaluable patients, median MLD, V5, V10, and V20 were 4.1 Gy, 20%, 12%, and 4%, respectively. Median MLDs were 4 Gy and 5 Gy for G0-1 and G2-4 groups, respectively (p = 0.14); median V5 was 20% for G0-1 and 24% for G2-4 (p = 0.70); median V10 was 12% in G0-1 and 16% in G2-4 (p = 0.08), and median V20 was 4% in G0-1 and 6.6% in G2-4 (p = 0.05). G2-4 RP was noted in 4.3% of patients with MLD {<=}4 Gy compared with 17.6% of patients with MLD >4 Gy (p = 0.02), and in 4.3% of patients with V20 {<=}4% compared with 16.4% of patients with V20 >4% (p = 0.03). Conclusion: Overall rate of G2-4 RP in our population treated with SBRT was 9.4%. Development of symptomatic RP in this series correlated with MLD and V20.

Barriger, R. Bryan [Department of Radiation Oncology, Indiana University School of Medicine, Indianapolis, IN (United States); Forquer, Jeffrey A. [Toledo Radiation Oncology Inc., Toledo, OH (United States); Department of Radiation Oncology, University of Toledo, Toledo, OH (United States); Brabham, Jeffrey G. [Florida Hospital Cancer Institute Waterman, Tavares, Florida (United States); Andolino, David L.; Shapiro, Ronald H.; Henderson, Mark A.; Johnstone, Peter A.S. [Department of Radiation Oncology, Indiana University School of Medicine, Indianapolis, IN (United States); Fakiris, Achilles J., E-mail: afakiris@iupui.edu [Department of Radiation Oncology, Indiana University School of Medicine, Indianapolis, IN (United States)

2012-01-01T23:59:59.000Z

350

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

SciTech Connect

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

351

Effective dose estimation during conventional and CT urography  

Science Journals Connector (OSTI)

Abstract Intravenous urography (IVU) and CT urography (CTU) are efficient radiological examinations for the evaluation of the urinary system disorders. However patients are exposed to a significant radiation dose. The objectives of this study are to: (i) measure and compare patient radiation dose by computed tomography urography (CTU) and conventional intravenous urography (IVU) and (ii) evaluate organ equivalent dose and cancer risks from CTU and IVU imaging procedures. A total of 141 patients were investigated. A calibrated CT machine (Siemens-Somatom Emotion duo) was used for CTU, while a Shimadzu X ray machine was used for IVU. Thermoluminescence dosimeters (TLD-GR200A) were used to measure patients' entrance surface doses (ESD). \\{TLDs\\} were calibrated under reproducible reference conditions. Patients radiation dose values (DLP) for CTU were 17261mGycm, \\{CTDIvol\\} 4.752mGy and effective dose 2.581mSv. Patient cancer probabilities were estimated to be 1.4 per million per CTU examination. Patients \\{ESDs\\} values for IVU were 21.625mGy, effective dose 1.791mSv. CT involves a higher effective dose than IVU. In this study the radiation dose is considered low compared to previous studies. The effective dose from CTU procedures was 30% higher compared to IVU procedures. Wide dose variation between patient doses suggests that optimization is not fulfilled yet.

K. Alzimami; A. Sulieman; E. Omer; I.I. Suliman; K. Alsafi

2014-01-01T23:59:59.000Z

352

Track-etched detectors for the dosimetry of the radiation of cosmic origin  

Science Journals Connector (OSTI)

......neutron dose equivalent component of the natural background using electrochemically etched polycarbonate detector and boron-10 radiator. Nucl. Tracks 20 , 573-576 (1986). 13. Lindborg, L., McAulay, I., Bartlett, T. D., Beck......

F. Spurny; K. Turek

2004-07-01T23:59:59.000Z

353

Low Dose Radiation Research Program: Kanokporn Noy Rithidech, Ph.D.  

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

Kanokporn Noy Rithidech, Ph.D. Kanokporn Noy Rithidech, Ph.D. University of New York at Stony Brook Currently Funded Projects Induction of Genomic Instability In vivo by Low Doses of 137Cs Gamma Rays Technical Abstracts 2006 Workshop: No Evidence for In Vivo Induction of Genomic Instability in Bone Marrow Cells Collected from Mice Exposed to Low-Dose 137CS γ Rays Rithidech, K.N., Loetchutinat, C., Honikel, L., and Whorton, E.B. 2005 Workshop: Induction of Genomic Instability in Vivo by Low Doses of 137Cs γ rays. Rithidech, K.N., Leotchutinat, C., Honikel, L., Simon, S.R. and Whorton, E.B. 2003 Workshop: Induction of Genomic Instability in vivo by Low Doses of 137Cs y rays Rithidech. K., Whorton, E.B., Tungjai, M., Ar-Bab, E., Simon, S.R. Tawde, M. and Anderson, C.W. 2002 Workshop: Induction of Genomic Instability In vivo by Low Doses of 137Cs gamma rays.

354

The Circadian Rhythm, A Continuous Transcription-Translation Feedback Loop, Contributes to Low-Dose Radiation-Induced Radioadaptive Response  

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

The Circadian Rhythm, A Continuous Transcription-Translation Feedback Loop, Contributes to Low-Dose Radiation-Induced Radioadaptive Response Aris Alexandrou and Jian Jian Li Department of Radiation Oncology, the University of California Davis, Sacramento, California, 95817 The initiation of the circadian rhythm field occurred when the Takahashi group defined a mutation in the mouse gene "Clock" and cloned the circadian locomotor output cycles kaput (Clock) in the mid- 1990's (1-3). Currently more than a dozen clock genes have been identified (3-4). Disruptions in the circadian rhythm via changes in environmental conditions, such as, diet, temperature, and night/day hours lead to the pathogenesis of a multitude of diseases, such as, cancer, diabetes mellitus,

355

GENII-LIN project: A multipurpose health physics code to estimate radiation dose and risk from environment contamination  

Science Journals Connector (OSTI)

Abstract GENII-LIN11 GENII is the name of the code precursor. LIN stands for Laboratorio di Ingegneria Nucleare, the laboratory where the code has been developed. is an open source radiation protection environmental code with capabilities for calculating radiation dose and risk to individuals or populations from radionuclides released to the environment and from pre-existing environmental contamination. The code can be used for purposes such as siting facilities, environmental impact statements, and safety analysis reports. The code can handle exposure pathways that include: external exposure from finite or infinite atmospheric plumes; inhalation; external exposure from contaminated soil, sediments, and water; external exposure from special geometries; and internal exposures from consumption of terrestrial foods, aquatic foods, drinking water, animal products, and inadvertent intake of soil. The flexible modular structure and the strictly object oriented software design simplify code improvement and patching: other modules can be added and the present ones updated, with minimal effort.

F. Teodori; M. Sumini

2014-01-01T23:59:59.000Z

356

Estimation of external gamma radiation dose in the area of Bory Stobrawskie forests (PL)  

Science Journals Connector (OSTI)

Rather poor relationship between E I and H...was found. The correlation coefficient value was 0.46, supposing existence of other important sources of gamma radiation in environment that were not i...

Agnieszka Do?ha?czuk-?rdka

2012-09-01T23:59:59.000Z

357

Radiation dose to members of public residing around uranium mining complex, Jaduguda, Jharkhand, India  

Science Journals Connector (OSTI)

......radionuclides may contaminate the ground water and deliver radiation...around the TP through water ingestion pathway. In...Characterisation and remediation of soils contaminated...uranium mill tailings, water, air, and soil pollution......

R. M. Tripathi; S. K. Sahoo; V. N. Jha; Rajesh Kumar; A. K. Shukla; V. D. Puranik; H. S. Kushwaha

2011-11-01T23:59:59.000Z

358

Distribution of uranium in drinking water and associated age-dependent radiation dose in India  

Science Journals Connector (OSTI)

......uranium in Argentina bottled mineral waters. Radiat. Prot. Dosim (1996...exposure to natural uranium in well water. J. Environ. Radioact (2002...Identification, investigation and remediation of ground water containing elevated levels of......

S. K. Sahoo; S. Mohapatra; A. Chakrabarty; C. G. Sumesh; V. N. Jha; R. M. Tripathi; V. D. Puranik

2009-09-01T23:59:59.000Z

359

Inference of Causal Networks from Time-course Transcription Data in Response to a2 Gy Challenge Dose of Ionizing Radiation with or without a 10 cGy Priming Dose  

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

Causal Networks from Time-course Transcription Data in Response to a Causal Networks from Time-course Transcription Data in Response to a 2 Gy Challenge Dose of Ionizing Radiation with or without a 10 cGy Priming Dose Kai Zhang, Ju Han, Torsten Groesser, Priscilla Cooper, and Bahram Parvin Lawrence Berkeley National Laboratory Goal: To elucidate temporal-dependent gene templates, causal networks, and underlying biological processes that can be inferred in response to a 10 cGy priming dose with or without a later higher challenged dose. Background and significance: Mechanistic inference of regulatory network can provide new insights into radiation systems biology. The main challenge continues to be high dimensionality of data, complex network architecture and limited knowledge of biological processes.

360

Doses and risks from uranium are not increased significantly by interactions with natural background photon radiation  

Science Journals Connector (OSTI)

......of doses to members of the public, since all humans are exposed...22). For members of the public, ingestion could also be an...Physics Society First Annual Meeting 25-27 June 1956. 33-48...United States Uranium Registry/Hanford Environmental Health Foundation......

R. J. Tanner; J. S. Eakins; J. T. M. Jansen; J. D. Harrison

2012-08-01T23:59:59.000Z

Note: This page contains sample records for the topic "radiation dose equivalent" 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

Central dose data management and analysis in IT-driven radiation protection strategies  

Science Journals Connector (OSTI)

......central dose data management system for use...requirements for such an approach are presented...central data management facility are...an M.Sc. in Science and Technology...noted. With this approach optimisation...thesis in X-ray Science and Technology...quality assurance management system in mammography......

M. Ward; D. Hughes; P. Connolly; B. M. Moores

2005-05-01T23:59:59.000Z

362

Radionuclides and radiation doses in heavy mineral sands and other mining operations in Mozambique  

Science Journals Connector (OSTI)

......commodities including oil, gas and coal...measurements made in the field, and aimed at identifying...the mine at full production is 800 000 ton per...2000-h exposure, the cumulative dose would be 40...associated to uranium production. Am. J. Environ...contamination from uranium production facilities and their......

Fernando P. Carvalho; Obete F. Matine; Suzete Tamo; Joo M. Oliveira; Ldia Silva; Margarida Malta

2014-01-01T23:59:59.000Z

363

Effect of low-dose, low-LET γ-radiation and BaP injection on pulmonary immunity in A/J mice  

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

low-dose, low-LET γ-radiation and BaP injection on pulmonary immunity in A/J mice low-dose, low-LET γ-radiation and BaP injection on pulmonary immunity in A/J mice K. Gott, V. Gonzales, M. Makvandi, N. Kikendall, A. Monier, E. Maloy, C. Rietz, B. Scott and J. Wilder. Lovelace Respiratory Research Institute, Albuquerque, NM Introduction: Low-dose, low-linear-energy-transfer (LET) radiation (LDR; < 100 mGy) activates the immune response (Nowosielska et al., 2006), presumably via epigenetic pathways (Scott et al., 2009) and has been implicated as suppressing both alpha-radiation-induced and smoking-related lung cancer (Scott et al. 2009). One of the hypothesized adaptive-response mechanisms by which LDR does so is by activating immune cell function in the lung, which would then increase their anti-cancer surveillance

364

Low-dose, low-LET γ-radiation alters carcinogen-induced splenic cytokine production and immune cell phenotype of A/J mice  

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

dose, low-LET γ-radiation alters carcinogen-induced splenic cytokine production and immune cell dose, low-LET γ-radiation alters carcinogen-induced splenic cytokine production and immune cell phenotype of A/J mice. V. Gonzales, K. Gott, M. Makvandi, N. Kikendall, A. Monier, E. Maloy, C. Rietz, B. Scott and J. Wilder. Lovelace Respiratory Research Institute, Albuquerque, NM. Introduction: Low-dose, low-linear-energy-transfer (LET) radiation (LDR; < 100 mGy) activates the immune response, presumably via epigenetic pathways (Scott et al. 2009) and may lead to cancer suppression (Nowosielska et al. 2006). One of the mechanisms by which it might do so is by altering the cytokines produced after carcinogen and/or radiation exposure. Alternatively, LDR may activate

365

Genetic susceptibility to low-dose ionizing radiation in the mouse mammary glandas a means of understanding human risk for breast cancer  

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

susceptibility to low-dose ionizing radiation in the mouse mammary gland susceptibility to low-dose ionizing radiation in the mouse mammary gland as a means of understanding human risk for breast cancer Antoine M. Snijders 1 , Francesco Marchetti 1 , Ju Han 1 , Sandhya Bhatnagar 1 , Nadire Duru 1 , Zhi Hu 1 , Jian-Hua Mao 1 , Mina Bissell 1 , Joe Gray 1,2 , Gary H. Karpen 1 , Priscilla K. Cooper 1 and Andrew J. Wyrobek 1 1 Life Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 2 Current affiliation: Biomedical Engineering, Oregon Health Science Univ, Portland, OR Goal: Our goal is to develop an in vivo mechanistic model of genetic variation in the low-dose damage responses of mammary glands using inbred mice known to vary in their sensitivity to low-dose induced mammary gland cancer, and to develop molecular predictors for susceptibility or resistance to low-dose induced breast cancer.

366

Recommendations to the Technical Steering Panel regarding approach for estimating individual radiation doses resulting from releases of radionuclides to the Columbia River  

SciTech Connect

At the direction of the Technical Steering Panel (TSP) of the Hanford Environmental Dose Reconstruction (HEDR) Project, Battelle staff have reviewed and analyzed available data regarding possible historical radiation doses to individuals resulting from radionuclide releases to the Columbia River. The objective of this review was to recommend to the TSP the spatial and temporal scope and level of effort on Columbia River work to most effectively extend work performed in Phase I of the project (PNL 1991a, PNL 1991b) to meet the project objectives. A number of options were analyzed. Four stretches of the Columbia River and adjacent Pacific coastal waters were defined and investigated for four time periods. Radiation doses arising from ten potentially major exposure pathways were evaluated for each of the time/location combinations, and several alternative methods were defined for estimating the doses from each pathway. Preliminary cost estimates were also developed for implementing dose estimation activities for each of the possible combinations.

Napier, B.A.; Brothers, A.J.

1992-07-01T23:59:59.000Z

367

Recommendations to the Technical Steering Panel regarding approach for estimating individual radiation doses resulting from releases of radionuclides to the Columbia River. Volume 1, Recommendations  

SciTech Connect

At the direction of the Technical Steering Panel (TSP) of the Hanford Environmental Dose Reconstruction (HEDR) Project, Battelle staff have reviewed and analyzed available data regarding possible historical radiation doses to individuals resulting from radionuclide releases to the Columbia River. The objective of this review was to recommend to the TSP the spatial and temporal scope and level of effort on Columbia River work to most effectively extend work performed in Phase I of the project (PNL 1991a, PNL 1991b) to meet the project objectives. A number of options were analyzed. Four stretches of the Columbia River and adjacent Pacific coastal waters were defined and investigated for four time periods. Radiation doses arising from ten potentially major exposure pathways were evaluated for each of the time/location combinations, and several alternative methods were defined for estimating the doses from each pathway. Preliminary cost estimates were also developed for implementing dose estimation activities for each of the possible combinations.

Napier, B.A.; Brothers, A.J.

1992-07-01T23:59:59.000Z

368

Applying the conventional moving average filter for estimation of low radiation doses using EPR spectroscopy: Benefits and drawbacks  

Science Journals Connector (OSTI)

Abstract Alanine/EPR is the most common dosimetry system for high radiation doses because of its high stability and wide linear response, however, use of alanine in most of medical applications still require special sophisticated methodologies and techniques in order to extend alanine detection limit to low levels of radiation doses. One of these techniques is the use of digital processing of acquired alanine spectra for enhancing useful components in spectra while useless features are suppressed. Simple moving average filter (MA) impacts on alanine EPR spectra have been studied in terms of peak-to-peak height, peak-to-peak line width, and associated uncertainty. Three types of the used filter were investigated: upward MA, central MA, and downward MA filters, effects of each on the peak position for different values of filter width were studied. It was found that MA filter always lead to the reduction in signal intensity and the increase of line width of the central peak of alanine spectrum. Peak position also changes in cases of the upward MA and downward MA filters while no significant changes were observed in the case of central MA. Uncertainties associated to the averaging process were evaluated and plotted versus the filter width resulting in a linear relationship. Filter width value should be carefully selected in order to avoid probable distortion in processed spectra while gaining less noisy spectra with less associated uncertainties.

Ahmed M. Maghraby

2014-01-01T23:59:59.000Z

369

Low Dose Radiation Research Program: Modeling the Physics of Damage Cluster  

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

Modeling the Physics of Damage Cluster Formation in a Cellular Environment Modeling the Physics of Damage Cluster Formation in a Cellular Environment Larry Toburen East Carolina University Why This Project Modern tools of radiobiology are leading to many new discoveries regarding how cells and tissues respond to radiation exposure. We can now irradiate single cells and observe responses in adjacent cells. We can also measure clusters of radiation damage produced in DNA. The primary tools available to describe the initial spatial pattern of damage formed by the absorption of ionizing radiation are based on (MC) Monte Carlo simulations of the structure of charged particle tracks. Although many MC codes exist and considerable progress is being made in the incorporation of detailed macromolecular target structures into these codes, much of the interaction

370

Sources Of Average Individual Radiation Exposure  

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

Of Average Individual Radiation Exposure Of Average Individual Radiation Exposure Natural background Medical Consumer products Industrial, security, educational and research Occupational 0.311 rem 0.300 rem 0.013 rem 0.0003 rem 0.0005 rem Savannah River Nuclear Solutions, LLC, provides radiological protection services and oversight at the Savannah River Site (SRS). These services include radiation dose measurements for persons who enter areas where they may be exposed to radiation or radioactive material. The results are periodically reported to monitored individuals. The results listed are based on a radiation dose system developed by the International Commission on Radiation Protection. The system uses the terms "effective dose," "equivalent dose" and units of rem. You may be more familiar with the term "millirem" (mrem), which is 1/1000 of a rem.

371

DOE-STD-1153-2002; A Graded Approach for Evaluating Radiation Doses to Aquatic and Terrestrial Biota  

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

3 3 METHODS DERIVATION MODULE 3: METHODS DERIVATION DOE-STD-1153-2002 INTENTIONALLY BLANK DOE-STD-1153-2002 M3-1 1 Introduction and Basis for the Approach The Department of Energy (DOE) currently has in place a radiation dose limit of 1 rad/d (10 mGy/d) for the protection of aquatic organisms (DOE Order 5400.5), and has proposed dose limits for both aquatic and terrestrial organisms. These limits are: 1 rad/d (10 mGy/d) for aquatic animals; 1 rad/d (10 mGy/d) for terrestrial plants; and 0.1 rad/d (1 mGy/d) for terrestrial animals. Because the biota protection limits are dose-based, a calculational method is needed to demonstrate compliance. In theory, derived radionuclide concentration limits for environmental media (e.g., Biota Concentration Guides, BCGs, for water, sediment, or soil) provide a relatively straightforward and simple means to do so. However, because of the

372

JOURNALDE PHYSIQUE Colloque C2, supplkment au nO 3, Tome 40, mars 1979, page C2-462 ESTIMATION OF NATURAL RADIATION DOSE AND OF THE AGE OF ANCIENT POTTERY BY MOSSBAUER  

E-Print Network (OSTI)

OF NATURAL RADIATION DOSE AND OF THE AGE OF ANCIENT POTTERY BY MOSSBAUER EFFECT 3E N.A. Eissa, H.A. Sallams was estimated to be 2960 + 90 years, assuming the 1 same annual dose. 3. Discussion and conclusion.- The obtained values / for the natural radiation dose are in agreement with those (0.3 to 0.4 radslyear) given

Paris-Sud XI, Université de

373

Rapid assessment of high-dose radiation exposures through scoring of cell-fusion-induced premature chromosome condensation and ring chromosomes  

Science Journals Connector (OSTI)

Abstract Analysis of premature chromosome condensation (PCC) mediated by fusion of G0-lymphocytes with mitotic CHO cells in combination with rapid visualization and quantification of rings (PCC-Rf) is proposed as an alternative technique for dose assessment of radiation-exposed individuals. Isolated lymphocytes or whole blood from six individuals were ?-irradiated with 5, 10, 15 and 20Gy at a dose rate of 0.5Gy/min. Following either 8- or 24-h post-exposure incubation of irradiated samples at 37C, chromosome spreads were prepared by standard PCC cytogenetic procedures. The protocol for PCC fusion proved to be effective at doses as high as 20Gy, enabling the analysis of ring chromosomes and excess PCC fragments. The ring frequencies remained constant during the 824-h repair time; the pooled dose relationship between ring frequency (Y) and dose (D) was linear: Y=(0.0880.005)נD. During the repair time, excess fragments decreased from 0.91 to 0.59 chromatid pieces per Gy, revealing the importance of information about the exact time of exposure for dose assessment on the basis of fragments. Compared with other cytogenetic assays to estimate radiation dose, the PCC-Rf method has the following benefits: a 48-h culture time is not required, allowing a much faster assessment of dose in comparison with conventional scoring of dicentrics and rings in assays for chemically-induced premature chromosome condensation (PCC-Rch), and it allows the analysis of heavily irradiated lymphocytes that are delayed or never reach mitosis, thus avoiding the problem of saturation at high doses. In conclusion, the use of the PCC fusion assay in conjunction with scoring of rings in G0-lymphocytes offers a suitable alternative for fast dose estimation following accidental exposure to high radiation doses.

A.I. Lamadrid Boada; I. Romero Aguilera; G.I. Terzoudi; J.E. Gonzlez Mesa; G. Pantelias; O. Garca

2013-01-01T23:59:59.000Z

374

Factors Affecting Radiation Dose from a Hypothetical Extrusive Volcanic Event at Yucca Mountain, Nevada  

SciTech Connect

This paper describes the factors that could affect doses to the reasonably maximally exposed individual (RMEI) as a result of a hypothetical extrusive igneous event at Yucca Mountain. Based on available information, there is no evidence that most of the spent fuel in waste packages intersected by a volcanic conduit would be reduced to fine-grained material and subsequently erupted as volcanic ash. (authors)

Weiner, R. [U. S. NRC Advisory Committee on Nuclear Waste and Materials, Rockville, MD (United States); Coleman, N. [U.S. Nuclear Regulatory Commission, Rockville, MD (United States)

2008-07-01T23:59:59.000Z

375

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-

376

Radiation dose profile in 125I brachytherapy: an 8-year review  

Science Journals Connector (OSTI)

......brachytherapy: an 8-year review A. N. Al-Haj...prepare the treatment plan. The radiation oncologists...KFSHRC Secondary Standard Dosimetry Laboratory...DNS-26 depleted uranium standard reference...brachytherapy: an 8-year review. | The use of episcleral...Journal Article Review | 0 Iodine Radioisotopes......

A. N. Al-Haj; A. M. Lobriguito; C. S. Lagarde

2004-08-01T23:59:59.000Z

377

Dosimetry experiences and lessons learned for radiation dose assessment in Korean nuclear power plants  

Science Journals Connector (OSTI)

......various long-term plans to reduce radiation...conducted by the regulatory body in Korea...and thorough review in order to apply...body counting, review of inhalation...15). The regulatory body has provided...from various reviews and studies...the mid-term plan for reduction......

Jong Rak Choi; Hee Geun Kim; Tae Young Kong; Jung Kwon Son

2013-07-01T23:59:59.000Z

378

Doses and risks from uranium are not increased significantly by interactions with natural background photon radiation  

Science Journals Connector (OSTI)

......retained in the skeleton is associated with mineral bone and is not incorporated into living...Pattison J. E. , Hugtenberg R. P., Green S. Enhancement of natural background gamma-radiation...R. , Khoury H. J., Viera J. W., Lime V. J. M. MAX06 and FAX06: update of......

R. J. Tanner; J. S. Eakins; J. T. M. Jansen; J. D. Harrison

2012-08-01T23:59:59.000Z

379

Internal Dose Estimates from  

E-Print Network (OSTI)

Appendix H Internal Dose Estimates from Global Fallout H-1 #12;Radiation Dose to the Population. 263-MQ-008090 September 30, 2000 H-2 #12;Radiation Dose to the Population of the Continental United Site Part I. Estimates of Dose Lynn R. Anspaugh Lynn R. Anspaugh, Consulting Salt Lake City, UT Report

380

Dose reconstruction for the Urals population. Joint Coordinating Committee on Radiation Effects Research, Project 1.1 -- Final report  

SciTech Connect

This work is being carried out as a feasibility study to determine if a long-term course of work can be implemented to assess the long-term risks of radiation exposure delivered at low to moderate dose rates to the populations living in the vicinity of the Mayak Industrial Association (MIA). This work was authorized and conducted under the auspices of the US-Russian Joint Coordinating Committee on Radiation Effects Research (JCCRER) and its Executive Committee (EC). The MIA was the first Russian site for the production and separation of plutonium. This plant began operation in 1948, and during its early days there were technological failures that resulted in the release of large amounts of waste into the rather small Techa River. There were also gaseous releases of radioiodines and other radionuclides during the early days of operation. In addition, there was an accidental explosion in a waste storage tank in 1957 that resulted in a significant release. The Techa River Cohort has been studied for several years by scientists from the Urals Research Centre for Radiation Medicine and an increase in both leukemia and solid tumors has been noted.

Degteva, M.O. [Urals Research Center for Radiation Medicine, Chelyabinsk (Russian Federation)] [Urals Research Center for Radiation Medicine, Chelyabinsk (Russian Federation); Drozhko, E. [Branch 1 of Moscow Biophysics Inst., Ozersk (Russian Federation)] [Branch 1 of Moscow Biophysics Inst., Ozersk (Russian Federation); Anspaugh, L.R. [Lawrence Livermore National Lab., CA (United States)] [Lawrence Livermore National Lab., CA (United States); Napier, B.A. [Pacific Northwest National Lab., Richland, WA (United States)] [Pacific Northwest National Lab., Richland, WA (United States); Bouville, A.C. [National Cancer Inst., Bethesda, MD (United States)] [National Cancer Inst., Bethesda, MD (United States); Miller, C.W. [Centers for Disease Control and Prevention, Atlanta, GA (United States)] [Centers for Disease Control and Prevention, Atlanta, GA (United States)

1996-02-01T23:59:59.000Z

Note: This page contains sample records for the topic "radiation dose equivalent" 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

Re-examination of the Linear No Threshold (LNT) hypothesis, and a trial for the public to comprehend the reality of the low-dose effects of radiation  

Science Journals Connector (OSTI)

People have imprinted knowledge of the LNT hypothesis. Use of the terms LNT hypothesis, ALARA, or stochastic effect, etc. clouds the understanding of people about the real effects of very low doses of radiation. In this paper, the scientific basis of the LNT hypothesis is re-examined. A denial of the presence of a threshold means that individuals have no protection from even very small doses or dose rates of radiation in the body. As the human population is heterogeneous, a linear dose-response curve is obtained, as even whole majorities have a threshold. Current results from radiation epidemiological studies and experimental studies from cells and animals were reported by experts from USA, Canada and Japan at the Radition Effects Association (REA) symposium in March 2005 in Tokyo. The findings did not support the LNT hypothesis, but the importance of biological reactions and factors involving radiation-carcinogenesis. Even a few antinuclear audiences started to think about the presence of a body-defence mechanism against radiation. Necessary information on radiation-carcinogenesis is summarised in several figures for better comprehensions by the public.

Junko Matsubara

2006-01-01T23:59:59.000Z

382

Low Dose Radiation Induced DNA Damage Signaling and Repair Responses in  

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

Induced DNA Damage Signaling and Repair Responses in Induced DNA Damage Signaling and Repair Responses in Human 3-Dimensional Skin Model System Yanrong Su, Jarah Meador and Adayabalam S. Balajee Center for Radiological Research, College of Physicians and Surgeons, Columbia University, 630 West, 168th Street, New York, NY 10032. Exposure to ionizing radiation (IR) inflicts a wide variety of lesions in the genomic DNA. Among them, DNA double strand break (DSB) is considered to be the critical lesion for most of the deleterious radiation effects including carcinogenesis. Much of our knowledge on induction and repair kinetics of DSB has come from studies in two dimensional cell culture systems. However, the damage signaling and repair responses to DSB in tissue microenvironment are largely unknown. Knowledge of tissue responses to

383

Assessment of Fukushima-Derived Radiation Doses and Effects on Wildlife in Japan  

Science Journals Connector (OSTI)

Following releases from the nuclear accident at the Fukushima-Daiichi Nuclear Power Station (FDNPS), contention has arisen over the potential radiological impact on wildlife. ... This work was conducted under the auspices of the UNSCEAR, and a more comprehensive version of the assessment presented here is reported within the UN publication Levels and effects of radiation exposure due to the nuclear accident after the 2011 Great East Japan earthquake and Tsunami. ...

P. Strand; T. Aono; J. E. Brown; J. Garnier-Laplace; A. Hosseini; T. Sazykina; F. Steenhuisen; J. Vives i Batlle

2014-02-14T23:59:59.000Z

384

Natural radioactivity in various water samples and radiation dose estimations in Bolu province, Turkey  

Science Journals Connector (OSTI)

Abstract The level of natural radioactivity for Bolu province of north-western Turkey was assessed in this study. There is no information about radioactivity measurement reported in water samples in the Bolu province so far. For this reason, gross ? and ? activities of 55 different water samples collected from tap, spring, mineral, river and lake waters in Bolu were determined. The mean activity concentrations were 68.11mBqL?1, 169.44mBqL?1 for gross ? and ? in tap water. For all samples the gross ? activity is always higher than the gross ? activity. All value of the gross ? were lower than the limit value of 500mBqL?1 while two spring and one mineral water samples were found to have gross ? activity concentrations of greater than 1000mBqL?1. The associated age-dependent dose from all water ingestion in Bolu was estimated. The total dose for adults had an average value exceeds the WHO recommended limit value. The risk levels from the direct ingestion of the natural radionuclides in tap and mineral water in Bolu were determinated. The mean 210Po and 228Ra risk the value of tap and mineral waters slightly exceeds what some consider on acceptable risk of 10?4 or less.

F. Korkmaz Gorur; H. Camgoz

2014-01-01T23:59:59.000Z

385

DOE-STD-1153-2002; A Graded Approach for Evaluating Radiation Doses to Aquatic and Terrestrial Biota  

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

2 2 DETAILED GUIDANCE MODULE 2: DETAILED GUIDANCE DOE-STD-1153-2002 INTENTIONALLY BLANK DOE-STD-1153-2002 M2-1 1 The Graded Approach, Ecological Risk Assessment, and Guidance on Their Implementation in Evaluating Radiation Doses to Biota The graded approach was made available to DOE field and program elements and to external users for a trial use period beginning in July 2000 as an interim version of this technical standard. The purpose of the trial period was to give users an opportunity to become familiar with and implement the graded approach at their sites, and to have an opportunity to provide suggestions and lessons learned to the BDAC regarding any refinements and associated guidance that needed to be incorporated into the graded approach prior to finalizing the technical standard. During this trial period the graded approach received strong interest and requests from

386

DOE-STD-1153-2002; A Graded Approach for Evaluating Radiation Doses to Aquatic and Terrestrial Biota  

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

1153-2002 1153-2002 July 2002 DOE STANDARD A GRADED APPROACH FOR EVALUATING RADIATION DOSES TO AQUATIC AND TERRESTRIAL BIOTA U.S. Department of Energy AREA ENVR Washington, D.C. 20585 DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. This document has been reproduced from the best available copy. Available to DOE and DOE contractors from ES&H Technical Information Services, U.S. Department of Energy, (800) 473-4375, fax: (301) 903-9823. Available to the public from the U.S. Department of Commerce, Technology Administration, National Technical Information Service, Springfield, VA 22161; (703) 605-6000. DOE-STD-1153-2002 iii Foreword 1. Department of Energy (DOE) activities may expose populations of plants and animals to radioactive materials in environmental media, or to radioactive materials released in waste streams. This DOE voluntary

387

The effect of thymosin on the survival of CBA/J mice exposed to lethal and acute doses of ionizing radiation  

E-Print Network (OSTI)

THE EFFECT OF THYMOSIN ON THE SURVIVAL OF CBA/J MICE EXPOSED TO LETHAL AND ACUTE DOSES OF IONIZING RADIATION A Thesis ROGER LYNN HUCHTON Submitted to the Graduate College of Texas A&M Unrversrty in partial fulfillment of the requirements... for the degree of MASTER OF SCIENCE August 1978 Major Subject: Biophysrcs THE EFFECT OF THYMQSIN ON THE SURVIVAL OF CBA/J MICE EXPOSED TO LETHAL AND ACUTE DOSES OF IONIZING RADIATION A Thesis by ROGER LYNN HUCHTQN Approved as to style and content by...

Huchton, Roger Lynn

1978-01-01T23:59:59.000Z

388

Alanine-EPR dosimetry for measurements of ionizing radiation absorbed doses in the range 0.5-10 kGy  

E-Print Network (OSTI)

The usefulness of two, easy accessible alanine dosimeters (ALANPOL from IChTJ and foil dosimeter from Gamma Service, Radeberg, Germany) to radiation dose measurement in the range of 0.5-10 kGy, were investigated. In both cases, the result of the test was positive. The foil dosemeter from Gamma Service is recommended for dose distribution measurements in fantoms or products, ALANPOL - for routine measurements. The EPR-alanine method based on the described dosimeters can be successfully used, among others, in the technology of radiation protection of food.

Peimel-Stuglik, Z

2001-01-01T23:59:59.000Z

389

Low dose radiation effects of multipotent neural stem and progenitor cells  

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

effects of multipotent neural stem and progenitor cells effects of multipotent neural stem and progenitor cells Charles L. Limoli, Department of Radiation Oncology, University of California, Irvine 92697-2695 Multipotent neural cells (both stem cells and their precursor cell progeny) retain their capacity to proliferate and differentiate throughout the mammalian lifespan. High numbers of these cells are located within the dentate subgranular zone (SGZ) of the hippocampus and the subventricular (SVZ) zone adjacent to the lateral ventricles, where they produce cells that can migrate away and differentiate into neurons (neurogenesis) and glia (gliogenesis). The realization that the brain contains such cells has sparked intense interest and speculation regarding their potential function. While significant data

390

Low Dose Radiation Research Program: A Variable-Energy Soft X-Ray  

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

A Variable-Energy Soft X-Ray Microprobe to Investigate Mechanisms of A Variable-Energy Soft X-Ray Microprobe to Investigate Mechanisms of the Radiation -Induced Bystander Effect. Authors: Melvyn Folkard, Borivoj Vojnovic, Giuseppe Schettino, Kirk Atkinson, Kevin M Prise, Barry D Michael Institutes: Gray Cancer Institute, PO Box 100, Mount Vernon Hospital, Northwood, HA6 2JR, UK For over a decade, the Gray Cancer Institute (GCI) has been actively engaged in the development and use of micro-irradiation techniques applied to radiobiological research. Our initial investigations made use of a charged-particle microbeam capable of irradiating individual cells with collimated energetic protons or 3He ions. By the end of the 1990's, a second facility had been constructed, which uses diffractive X-ray optics to focus ultrasoft X-rays to a sub-micron spot. The X-ray microprobe was

391

Low Dose Radiation Research Program: Real-time Study of Signal Transduction  

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

Real-time Study of Signal Transduction Pathways Involving in Real-time Study of Signal Transduction Pathways Involving in Bystander Effects Using Single Nanoparticle Optics and Single Living Cell Imaging Authors: Prakash D. Nallathamby, X. Nancy Xu, Mohan Natarajan Institutions: Department of Chemistry and Biochemistry, Old Dominion University, Norfolk, Virginia and Department of Radiation Oncology, The University of Texas Health Science Center, San Antonio, Texas The mechanisms of bystander effects remain largely unknown. Bystander responses are thought to depend on activation of cellular communication processes. Recent studies have speculated that several crucial signal transduction pathways could play a major role in bystander effects. These crucial signal transduction pathways are controlled by a coordinated

392

Community Surveys: Low Dose Radiation. Fernald, Ohio and Rocky Flats, Colorado  

SciTech Connect

This report is intended to present a basic description of the data from the two community surveys and to document the text of the questions; the methods used for the survey data collection; and a brief overview of the results. Completed surveys were conducted at local communities near the Rocky Flats, Colorado and the Fernald, Ohio sites; no survey was conducted for the Brookhaven, New York site. Fernald. The Fernald sample was randomly selected from 98% of all potential residential telephones in the townships of Ross, Morgan, and Crosby. The only telephone exchanges not used for the Fernald study had 4%, or fewer, of the holders of the telephone numbers actually living in either of the three target townships. Surveying started on July 24, 2001 and finished on August 30, 2001. A total of 399 completed interviews were obtained resulting in a CASRO response rate of 41.8%. The average length of an interview was 16.5 minutes. Rocky Flats. The sample was randomly selected from all potential residential telephones in Arvada and from 99% of the potential telephones in Westminster. Surveying started on August 10, 2001 and finished on September 25, 2001. A total of 401 completed interviews were obtained with a CASRO response rate of 32.5%. The average length of an interview was 15.7 minutes. Overall, respondents hold favorable views of science. They indicate an interest in developments in science and technology, feel that the world is better off because of science, and that science makes our lives healthier, easier, and more comfortable. However, respondents are divided on whether science should decide what is safe or not safe for themselves and their families. The majority of the respondents think that standards for exposure to radiation should be based on what science knows about health effects of radiation and on what is possible with today's technology. Although few respondents had visited the sites, most had heard or read something about Fernald or Rocky Flat s in the media. Impressions of the sites tend to be negative. Most respondents feel that overall their community would be better off without the site. However, when asked about the economic future of their community after cleanup and closure of the site, only 31-43% thought that it will be better, 47-56% thought their local economy will be about the same.

C. K. Mertz; James Flynn; Donald G. MacGregor; Theresa Satterfield; Stephen M. Johnson; Seth Tuler; Thomas Webler

2002-10-16T23:59:59.000Z

393

A Phase I/II Trial of Intensity Modulated Radiation (IMRT) Dose Escalation With Concurrent Fixed-dose Rate Gemcitabine (FDR-G) in Patients With Unresectable Pancreatic Cancer  

SciTech Connect

Purpose: Local failure in unresectable pancreatic cancer may contribute to death. We hypothesized that intensification of local therapy would improve local control and survival. The objectives were to determine the maximum tolerated radiation dose delivered by intensity modulated radiation with fixed-dose rate gemcitabine (FDR-G), freedom from local progression (FFLP), and overall survival (OS). Methods and Materials: Eligibility included pathologic confirmation of adenocarcinoma, radiographically unresectable, performance status of 0-2, absolute neutrophil count of {>=}1500/mm{sup 3}, platelets {>=}100,000/mm{sup 3}, creatinine <2 mg/dL, bilirubin <3 mg/dL, and alanine aminotransferase/aspartate aminotransferase {<=}2.5 Multiplication-Sign upper limit of normal. FDR-G (1000 mg/m{sup 2}/100 min intravenously) was given on days -22 and -15, 1, 8, 22, and 29. Intensity modulated radiation started on day 1. Dose levels were escalated from 50-60 Gy in 25 fractions. Dose-limiting toxicity was defined as gastrointestinal toxicity grade (G) {>=}3, neutropenic fever, or deterioration in performance status to {>=}3 between day 1 and 126. Dose level was assigned using TITE-CRM (Time-to-Event Continual Reassessment Method) with the target dose-limiting toxicity (DLT) rate set to 0.25. Results: Fifty patients were accrued. DLTs were observed in 11 patients: G3/4 anorexia, nausea, vomiting, and/or dehydration (7); duodenal bleed (3); duodenal perforation (1). The recommended dose is 55 Gy, producing a probability of DLT of 0.24. The 2-year FFLP is 59% (95% confidence interval [CI]: 32-79). Median and 2-year overall survival are 14.8 months (95% CI: 12.6-22.2) and 30% (95% CI 17-45). Twelve patients underwent resection (10 R0, 2 R1) and survived a median of 32 months. Conclusions: High-dose radiation therapy with concurrent FDR-G can be delivered safely. The encouraging efficacy data suggest that outcome may be improved in unresectable patients through intensification of local therapy.

Ben-Josef, Edgar, E-mail: edgar.ben-josef@uphs.upenn.edu [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States)] [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States); Schipper, Mathew [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States)] [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States); Francis, Isaac R. [Department of Radiology, University of Michigan, Ann Arbor, Michigan (United States)] [Department of Radiology, University of Michigan, Ann Arbor, Michigan (United States); Hadley, Scott; Ten-Haken, Randall; Lawrence, Theodore; Normolle, Daniel [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States)] [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States); Simeone, Diane M.; Sonnenday, Christopher [Department of Surgery, University of Michigan, Ann Arbor, Michigan (United States)] [Department of Surgery, University of Michigan, Ann Arbor, Michigan (United States); Abrams, Ross [Department of Radiation Oncology, Rush Medical Center, Chicago, Illinois (United States)] [Department of Radiation Oncology, Rush Medical Center, Chicago, Illinois (United States); Leslie, William [Division of Hematology Oncology, Department of Internal Medicine, Rush Medical Center, Chicago, Illinois (United States)] [Division of Hematology Oncology, Department of Internal Medicine, Rush Medical Center, Chicago, Illinois (United States); Khan, Gazala; Zalupski, Mark M. [Division of Hematology Oncology, Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan (United States)] [Division of Hematology Oncology, Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan (United States)

2012-12-01T23:59:59.000Z

394

Development of Real-Time Measurement of Effective Dose for High Dose Rate Neutron Fields  

SciTech Connect

Studies of the effects of low doses of ionizing radiation require sources of radiation which are well characterized in terms of the dose and the quality of the radiation. One of the best measures of the quality of neutron irradiation is the dose mean lineal energy. At very low dose rates this can be determined by measuring individual energy deposition events, and calculating the dose mean of the event size. However, at the dose rates that are normally required for biology experiments, the individual events can not be separated by radiation detectors. However, the total energy deposited in a specified time interval can be measured. This total energy has a random variation which depends on the size of the individual events, so the dose mean lineal energy can be calculated from the variance of repeated measurements of the energy deposited in a fixed time. We have developed a specialized charge integration circuit for the measurement of the charge produced in a small ion chamber in typical neutron irradiation experiments. We have also developed 4.3 mm diameter ion chambers with both tissue equivalent and carbon walls for the purpose of measuring dose mean lineal energy due to all radiations and due to all radiations except neutrons, respectively. By adjusting the gas pressure in the ion chamber, it can be made to simulate tissue volumes from a few nanometers to a few millimeters in diameter. The charge is integrated for 0.1 seconds, and the resulting pulse height is recorded by a multi channel analyzer. The system has been used in a variety of photon and neutron radiation fields, and measured values of dose and dose mean lineal energy are consistent with values extrapolated from measurements made by other techniques at much lower dose rates. It is expected that this technique will prove to be much more reliable than extrapolations from measurements made at low dose rates because these low dose rate exposures generally do not accurately reproduce the attenuation and scattering environment of the actual radiation exposure.

L. A. Braby; W. D. Reece; W. H. Hsu

2003-08-29T23:59:59.000Z

395

Standard Practice for Application of Thermoluminescence-Dosimetry (TLD) Systems for Determining Absorbed Dose in Radiation-Hardness Testing of Electronic Devices  

E-Print Network (OSTI)

1.1 This practice covers procedures for the use of thermoluminescence dosimeters (TLDs) to determine the absorbed dose in a material irradiated by ionizing radiation. Although some elements of the procedures have broader application, the specific area of concern is radiation-hardness testing of electronic devices. This practice is applicable to the measurement of absorbed dose in materials irradiated by gamma rays, X rays, and electrons of energies from 12 to 60 MeV. Specific energy limits are covered in appropriate sections describing specific applications of the procedures. The range of absorbed dose covered is approximately from 10?2 to 104 Gy (1 to 106 rad), and the range of absorbed dose rates is approximately from 10?2 to 1010 Gy/s (1 to 1012 rad/s). Absorbed dose and absorbed dose-rate measurements in materials subjected to neutron irradiation are not covered in this practice. Further, the portion of these procedures that deal with electron irradiation are primarily intended for use in parts testin...

American Society for Testing and Materials. Philadelphia

2010-01-01T23:59:59.000Z

396

Primate polonium metabolic models and their use in estimation of systemic radiation doses from bioassay data. Final report  

SciTech Connect

A Polonium metabolic model was derived and incorporated into a Fortran algorithm which estimates the systemic radiation dose from {sup 210}Po when applied to occupational urine bioassay data. The significance of the doses estimated are examined by defining the degree of uncertainty attached to them through comprehensive statistical testing procedures. Many parameters necessary for dosimetry calculations (such as organ partition coefficients and excretion fractions), were evaluated from metabolic studies of {sup 210}Po in non-human primates. Two tamarins and six baboons were injected intravenously with {sup 210}Po citrate. Excreta and blood samples were collected. Five of the baboons were sacrificed at times ranging from 1 day to 3 months post exposure. Complete necropsies were performed and all excreta and the majority of all skeletal and tissue samples were analyzed radiochemically for their {sup 210}Po content. The {sup 210}Po excretion rate in the baboon was more rapid than in the tamarin. The biological half-time of {sup 210}Po excretion in the baboon was approximately 15 days while in the tamarin, the {sup 210}Po excretion rate was in close agreement with the 50 day biological half-time predicted by ICRP 30. Excretion fractions of {sup 210}Po in the non-human primates were found to be markedly different from data reported elsewhere in other species, including man. A thorough review of the Po urinalysis procedure showed that significant recovery losses resulted when metabolized {sup 210}Po was deposited out of raw urine. Polonium-210 was found throughout the soft tissues of the baboon but not with the partition coefficients for liver, kidneys, and spleen that are predicted by the ICRP 30 metabolic model. A fractional distribution of 0.29 for liver, 0.07 for kidneys, and 0.006 for spleen was determined. Retention times for {sup 210}Po in tissues are described by single exponential functions with biological half-times ranging from 15 to 50 days.

Cohen, N. [New York Univ. Medical Center, Tuxedo, NY (United States). Dept. of Environmental Medicine

1989-03-15T23:59:59.000Z

397

Verification of radiation dose calculations during paediatric cystourethrography examinations using MCNP5 and PCXMC 2.0 Monte Carlo codes  

Science Journals Connector (OSTI)

......Cranley et al.) software code(21). For...Finnish Centre for Radiation and Nuclear Safety STUK). PCXMC is...Georgiou E. Radiation risk assessment...Finnish Centre for Radiation and Nuclear Safety. STUK-A231......

E. Yakoumakis; A. Dimitriadis; T. Makri; M. Karlatira; E. Karavasilis; G. Gialousis

2013-12-01T23:59:59.000Z

398

Mitigation Effect of an FGF-2 Peptide on Acute Gastrointestinal Syndrome After High-Dose Ionizing Radiation  

SciTech Connect

Purpose: Acute gastrointestinal syndrome (AGS) resulting from ionizing radiation causes death within 7 days. Currently, no satisfactory agent exists for mitigation of AGS. A peptide derived from the receptor binding domain of fibroblast growth factor 2 (FGF-P) was synthesized and its mitigation effect on AGS was examined. Methods and Materials: A subtotal body irradiation (sub-TBI) model was created to induce gastrointestinal (GI) death while avoiding bone marrow death. After 10.5 to 16 Gy sub-TBI, mice received an intramuscular injection of FGF-P (10 mg/kg/day) or saline (0.2 ml/day) for 5 days; survival (frequency and duration) was measured. Crypt cells and their proliferation were assessed by hematoxylin, eosin, and BrdU staining. In addition, GI hemoccult score, stool formation, and plasma levels of endotoxin, insulin, amylase, interleukin (IL)-6, keratinocyte-derived chemokine (KC) monocyte chemoattractant protein 1 (MCP-1) and tumor necrosis factor (TNF)-alpha were evaluated. Results: Treatment with FGF-P rescued a significant fraction of four strains of mice (33-50%) exposed to a lethal dose of sub-TBI. Use of FGF-P improved crypt survival and repopulation and partially preserved or restored GI function. Furthermore, whereas sub-TBI increased plasma endotoxin levels and several pro-inflammation cytokines (IL-6, KC, MCP-1, and TNF-alpha), FGF-P reduced these adverse responses. Conclusions: The study data support pursuing FGF-P as a mitigator for AGS.

Zhang Lurong [Department of Radiation Oncology, University of Rochester Medical Center, Rochester, NY (United States); Sun Weimin; Wang Jianjun [Second Military Medical College, Shanghai (China); Zhang Mei; Yang Shanmin [Department of Radiation Oncology, University of Rochester Medical Center, Rochester, NY (United States); Tian Yeping [Second Military Medical College, Shanghai (China); Vidyasagar, Sadasivan [Department of Radiation Oncology, University of Rochester Medical Center, Rochester, NY (United States); Pena, Louis A. [Brookhaven National Laboratory, Medical Department, Upton, NY (United States); Zhang Kunzhong [Department of Radiation Oncology, University of Rochester Medical Center, Rochester, NY (United States); Cao Yongbing [Second Military Medical College, Shanghai (China); Yin Liangjie [Department of Radiation Oncology, University of Rochester Medical Center, Rochester, NY (United States); Wang Wei [Department of Surgery, Second Affiliated Hospital of Fujian Medical University, Quanzhou, Fujian (China); Zhang Lei [Department of Laboratory Medicine, West China Hospital of Sichuan University, Chengdu, Sichuan (China); Schaefer, Katherine L.; Saubermann, Lawrence J. [Department of Medicine, University of Rochester Medical Center, Rochester, NY (United States); Swarts, Steven G.; Fenton, Bruce M.; Keng, Peter C. [Department of Radiation Oncology, University of Rochester Medical Center, Rochester, NY (United States); Okunieff, Paul, E-mail: Paul_Okunieff@URMC.Rochester.ed [Department of Radiation Oncology, University of Rochester Medical Center, Rochester, NY (United States)

2010-05-01T23:59:59.000Z

399

An investigation of radon exhalation rate and estimation of radiation doses in coal and fly ash samples  

Science Journals Connector (OSTI)

Coal is a technologically important material used for power generation. Its cinder (fly ash) is used in the manufacturing of bricks, sheets, cement, land filling etc. Coal and its by-products often contain significant amounts of radionuclides, including uranium which is the ultimate source of the radioactive gas radon. Burning of coal and the subsequent atmospheric emission cause the redistribution of toxic radioactive trace elements in the environment. In the present study, radon exhalation rates in coal and fly ash samples from the thermal power plants at Kolaghat (W.B.) and Kasimpur (U.P.) have been measured using sealed Can technique having LR-115 type II detectors. The activity concentrations of 238U, 232Th, and 40K in the samples of Kolaghat power station are also measured. It is observed that the radon exhalation rate from fly ash samples from Kolaghat is higher than from coal samples and activity concentration of radionuclides in fly ash is enhanced after the combustion of coal. Fly ash samples from Kasimpur show no appreciable change in radon exhalation. Radiation doses from the fly ash samples have been estimated from radon exhalation rate and radionuclide concentrations.

A.K. Mahur; Rajesh Kumar; Meena Mishra; D. Sengupta; Rajendra Prasad

2008-01-01T23:59:59.000Z

400

RADIATION DOSE ASSESSMENT FOR THE BIOTA OF TERRESTRIAL ECOSYSTEMS IN THE SHORELINE ZONE OF THE CHERNOBYL NUCLEAR POWER PLANT COOLING POND  

SciTech Connect

Radiation exposure of the biota in the shoreline area of the Chernobyl Nuclear Power Plant Cooling Pond was assessed to evaluate radiological consequences from the decommissioning of the Cooling Pond. The article addresses studies of radioactive contamination of the terrestrial faunal complex and radionuclide concentration ratios in bodies of small birds, small mammals, amphibians, and reptiles living in the area. The data were used to calculate doses to biota using the ERICA Tool software. Doses from {sup 90}Sr and {sup 137}Cs were calculated using the default parameters of the ERICA Tool and were shown to be consistent with biota doses calculated from the field data. However, the ERICA dose calculations for plutonium isotopes were much higher (2-5 times for small mammals and 10-14 times for birds) than the doses calculated using the experimental data. Currently, the total doses for the terrestrial biota do not exceed maximum recommended levels. However, if the Cooling Pond is allowed to drawdown naturally and the contaminants of the bottom sediments are exposed and enter the biological cycle, the calculated doses to biota may exceed the maximum recommended values. The study is important in establishing the current exposure conditions such that a baseline exists from which changes can be documented following the lowering of the reservoir water. Additionally, the study provided useful radioecological data on biota concentration ratios for some species that are poorly represented in the literature.

Farfan, E.; Jannik, T.

2011-10-01T23:59:59.000Z

Note: This page contains sample records for the topic "radiation dose equivalent" 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.


401

A dosimetric evaluation of dose escalation for the radical treatment of locally advanced vulvar cancer by intensity-modulated radiation therapy  

SciTech Connect

The purpose of this planning study was to determine whether intensity-modulated radiation therapy (IMRT) reduces the radiation dose to organs at risk (OAR) when compared with 3D conventional radiation therapy (3D-CRT) in patients with vulvar cancer treated by irradiation. This study also investigated the use of sequential IMRT boost (seq-IMRT) and simultaneous integrated boost (SIB-IMRT) for dose escalation in the treatment of locally advanced vulvar cancer. Five vulvar cancer patients treated in the postoperative setting and 5 patients treated with definitive intent (def-group) were evaluated. For the postoperative group, 3D-CRT and IMRT plans to a total dose (TD) of 45 Gy were generated. For the def-group, 4 plans were generated: a 3D-CRT and an IMRT plan to a TD of 56.4 Gy, a SIB-IMRT plan to a TD of 56 Gy, and a SIB-IMRT with dose escalation (SIB-IMRT-esc): TD of 67.2 Gy. Mean dose and dose-volume histograms were compared using Student's t-test. IMRT significantly (all p < 0.05) reduced the D{sub mean}, V30, and V40 for all OAR in the adjuvant setting. The V45 was also significantly reduced for all OAR except the bladder. For patients treated in the def-group, all IMRT techniques significantly reduced the D{sub mean}, V40, and V45 for all OAR. The mean femur doses with SIB-IMRT and SIB-IMRT-esc were 47% and 49% lower compared with 3D-CRT. SIB-IMRT-esc reduced the doses to the OAR compared with seq-3D-CRT but increased the D{sub max.} for the small bowel, rectum, and bladder. IMRT reduces the dose to the OAR compared with 3D-CRT in patients with vulvar cancer receiving irradiation to a volume covering the vulvar region and nodal areas without compromising the dosimetric coverage of the target volume. IMRT for vulvar cancer is feasible and an attractive option for dose escalation studies.

Bloemers, Monique C.W.M., E-mail: c.bloemers@nki.nl [Department of Radiotherapy, the Netherlands Cancer Institute, Amsterdam (Netherlands); Department of Radiation Oncology, McGill University Health Centre, Montreal, Quebec (Canada); Portelance, Lorraine [Department of Radiation Oncology, McGill University Health Centre, Montreal, Quebec (Canada); Ruo, Russell; Parker, William [Department of Medical Physics, McGill University Health Centre, Montreal, Quebec (Canada); Souhami, Luis [Department of Radiation Oncology, McGill University Health Centre, Montreal, Quebec (Canada)

2012-10-01T23:59:59.000Z

402

Translocation analysis by the FISH-painting method for retrospective dose reconstruction in individuals exposed to ionizing radiation 10 years after exposure  

Science Journals Connector (OSTI)

Fluorescence in situ hybridization (FISH) is a powerful method largely used for detecting chromosomal rearrangements, translocations in particular, which are important biomarkers for dose assessment in case of human exposure to ionizing radiation. To test the possibility of using the translocation analysis by FISH-painting method in retrospective dose assessment, we carried out in vitro experiments in irradiated human lymphocytes, in parallel with the analysis of translocations in lymphocytes from 10 individuals, who were exposed to 137cesium in the Goinia (Brazil) accident (samples collected 10 years after exposure). The in vitro doseresponse curve for the genomic translocation frequencies (FGs) fits a linear quadratic model, according to the equation: Y=0.0243X2+0.0556X. The FG values were also calculated for the individuals exposed to 137cesium, ranging from 0.58 to 5.91 per 100 cells, and the doses were estimated and compared with the results obtained by dicentric analysis soon after the accident, taking the opportunity to test the validity of translocation analysis in retrospective biodosimetry. A tentative of retrospective dosimetry was performed, indicating that the method is feasible only for low level exposure (below 0.5Gy), while for higher doses there is a need to apply appropriate correction factors, which take into consideration mainly the persistence of chromosomal translocations along with time, and the influence of endogenous and exogenous factors determining the inter-individual variability in the cellular responses to radiation.

Marjori L. Camparoto; Adriana T. Ramalho; Adayapalam T. Natarajan; Maria P. Curado; Elza T. Sakamoto-Hojo

2003-01-01T23:59:59.000Z

403

Patterns of Local Recurrence and Dose Fractionation of Adjuvant Radiation Therapy in 462 Patients With Soft Tissue Sarcoma of Extremity and Trunk Wall  

SciTech Connect

Purpose: To study the impact of dose fractionation of adjuvant radiation therapy (RT) on local recurrence (LR) and the relation of LR to radiation fields. Methods and Materials: LR rates were analyzed in 462 adult patients with soft tissue sarcoma who underwent surgical excision and adjuvant RT at five Scandinavian sarcoma centers from 1998 to 2009. Medical records were reviewed for dose fractionation parameters and to determine the location of the LR relative to the radiation portals. Results: Fifty-five of 462 patients developed a LR (11.9%). Negative prognostic factors included intralesional surgical margin (hazard ratio [HR]: 7.83, 95% confidence interval [CI]: 3.08-20.0), high malignancy grade (HR: 5.82, 95% CI: 1.31-25.8), age at diagnosis (HR per 10 years: 1.27, 95% CI: 1.03-1.56), and malignant peripheral nerve sheath tumor histological subtype (HR: 6.66, 95% CI: 2.56-17.3). RT dose was tailored to margin status. No correlation between RT dose and LR rate was found in multiple Cox regression analysis. The majority (65%) of LRs occurred within the primary RT volume. Conclusions: No significant doseresponse effect of adjuvant RT was demonstrated. Interestingly, patients given 45-Gy accelerated RT (1.8 Gy twice daily/2.5 weeks) had the best local outcome. A total dose of 50 Gy in 25 fractions seemed adequate following wide margin surgery. The risk of LR was associated with histopathologic subtype, which should be included in the treatment algorithm of adjuvant RT in soft tissue sarcoma.

Jebsen, Nina L., E-mail: nina.louise.jebsen@helse-bergen.no [Department of Clinical Medicine, Faculty of Medicine and Dentistry, University of Bergen, Bergen (Norway); Department of Oncology, Haukeland University Hospital, Bergen (Norway); Engellau, Jacob [Department of Oncology, Skne University Hospital, Lund (Sweden); Engstrm, Katarina [Department of Oncology, Sahlgrenska University Hospital, Gothenburg (Sweden); Bauer, Henrik C. [Department of Molecular Medicine and Surgery, Section for Orthopaedics and Sports Medicine, Karolinska University Hospital, Karolinska Institute, Stockholm (Sweden); Monge, Odd R. [Department of Oncology, Haukeland University Hospital, Bergen (Norway); Muren, Ludvig P. [Department of Physics and Technology, University of Bergen, Bergen (Norway); Department of Medical Physics, Aarhus University and Aarhus University Hospital, Aarhus (Denmark); Eide, Geir E. [Centre for Clinical Research, Haukeland University Hospital, Bergen (Norway); Department of Public Health and Primary Health Care, University of Bergen, Bergen (Norway); Trovik, Clement S. [Department of Clinical Medicine, Faculty of Medicine and Dentistry, University of Bergen, Bergen (Norway); Department of Oncology, Haukeland University Hospital, Bergen (Norway); Bruland, yvind S. [Department of Oncology, The Norwegian Radium Hospital, Oslo University Hospital, Oslo (Norway); Institute of Clinical Medicine, University of Oslo, Oslo (Norway)

2013-08-01T23:59:59.000Z

404

Development and comparison of computational models for estimation of absorbed organ radiation dose in rainbow trout (Oncorhynchus mykiss) from uptake of iodine-131  

Science Journals Connector (OSTI)

Abstract This study develops and compares different, increasingly detailed anatomical phantoms for rainbow trout (Oncorhynchus mykiss) for the purpose of estimating organ absorbed radiation dose and dose rates from 131I uptake in multiple organs. The models considered are: a simplistic geometry considering a single organ, a more specific geometry employing additional organs with anatomically relevant size and location, and voxel reconstruction of internal anatomy obtained from CT imaging (referred to as CSUTROUT). Dose Conversion Factors (DCFs) for whole body as well as selected organs of O.mykiss were computed using Monte Carlo modeling, and combined with estimated activity concentrations, to approximate dose rates and ultimately determine cumulative radiation dose (?Gy) to selected organs after several half-lives of 131I. The different computational models provided similar results, especially for source organs (less than 30% difference between estimated doses), and whole body \\{DCFs\\} for each model (?3נ10?3?Gyd?1perBqkg?1) were comparable to \\{DCFs\\} listed in ICRP 108 for 131I. The main benefit provided by the computational models developed here is the ability to accurately determine organ dose. A conservative mass-ratio approach may provide reasonable results for sufficiently large organs, but is only applicable to individual source organs. Although CSUTROUT is the more anatomically realistic phantom, it required much more resource dedication to develop and is less flexible than the stylized phantom for similar results. There may be instances where a detailed phantom such as CSUTROUT is appropriate, but generally the stylized phantom appears to be the best choice for an ideal balance between accuracy and resource requirements.

N.E. Martinez; T.E. Johnson; K. Capello; J.E. Pinder III

2014-01-01T23:59:59.000Z

405

Proteasome Structures Affected by Ionizing Radiation  

Science Journals Connector (OSTI)

...Effect of ionizing radiation on 26S but...radiation doses, and immediately...the dose range 1 to 20 Gy...ionizing radiation induced a...38), ionizing radiation (39...over a wide range of radiation doses and further...

Milena Pervan; Keisuke S. Iwamoto; and William H. McBride

2005-07-01T23:59:59.000Z

406

SU?FF?T?174: Dose Rate Dependence of Film Dosimetry in Radiation Treatment: Study of Reciprocity Law  

Science Journals Connector (OSTI)

Purpose: Film has become an important tool for dose verification in individualized IMRTtreatment fields. The optical density (OD) is related to dose rate also known as reciprocity law; (D= Dr*t). However for modern films (EDR and XV) reciprocity law has not been investigated which is presented in this study. Method and Materials: Using a Varian linear accelerator dose rate dependence was studied for Kodak films (XV and EDR). The dose rate on this unit could be varied in the range of 80400 MU/min for both (6 MV and 15 MV) photons beams. A large dose rate range; 5 cGy/min ?1100 cGy/min was achieved in conjunction with distance (14 meters) and machine dose rate. This was verified using ion chamber. At each dose rate films were exposed in a solid phantom at a depth of dmax for 300 cGy and 50 cGy for EDR and XV films respectively. Calibration curves (dose vs. OD) were also established during this experiment in a standard condition. The measured dose through film and ion chamber were compared and analyzed. Results: Reciprocity law holds good in the dose rate range of 20400 cGy/min for both energies but deviates at low and high dose rates. The effect is more pronounced at dose rate beyond 400 cGy/min where deviation up to 7.5% was noted for both the films. At low dose rate the deviation is ?3.5% for both films and energies. Conclusion: Low and high dose regions are created in the same time of exposure in IMRT and hence reciprocity law becomes critical for film dosimetry. The reciprocity law failure is due to the interaction of ion pairs to form latent image which could be suppressed at extreme dose rates. The dosimetric impact is noted to be up to 7.5% for both films.

S Srivastava; I Das

2006-01-01T23:59:59.000Z

407

SCIENTIFIC CORRESPONDENCE Radiation doses  

E-Print Network (OSTI)

the workforce, and Pollution and the Persian Gulf SIR - The waters of the Persian Gulf are not well confined. The average annual evaporation rate of the Persian Gulf is about 1.5 m yr-`(ref. 1). Esti- mates of relevant, despite the narrowness of the Strait of Hormuz, which links the Gulf to the Arabian Sea. Renewal of Gulf

Shlyakhter, Ilya

408

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

409

GROUND-WATER CONTRIBUTION TO DOSE FROM PAST HANFORD OPERATIONS  

SciTech Connect

The Hanford Environmental Dose Reconstruction (HEOR) Project is being conducted to estimate radiation doses that populations and individuals could have received from Hanford Site operations from 1944 to the present. Four possible pathways by which radionuclides originating in ground water on the Hanford Site could have reached the public have been identified: 1) through contaminated ground water migrating to the Columbia River; 2) through wells on or adjacent to the Hanford Site; 3) through wells that draw some or all of their water from the Columbia River (riparian wells); and 4) through atmospheric deposition resulting in the contamination of a small watershed that, in turn, results in contamination of a shallow well or spring. These four pathways make up the "ground-water pathway ," which is the subject of this study. The objective of the study was to assess the extent to which the groundwater pathway contributed to radiation doses that populations or individuals may have received from past operations at Hanford. The assessment presented in this report was performed by 1) reviewing the extensive ?literature on ground water and ground-water monitoring at Hanford and 2) performing simple calculations to estimate radionuclide concentrations in ground water and the Columbia River resulting from ground-water discharge. Radiation doses that would result from exposure to this ground water and surface water were calculated. The study conclusion is that the ground-water pathways did not contribute significantly to dose. Compared with background radiation in the TriCities {300 mrem/yr), estimated doses are small: 0.02 mrem/yr effective dose equivalent from discharge of contaminated ground water to the Columbia River; 1 mrem/yr effective dose equivalent from Hanford Site wells; 11 mrem/yr effective dose equivalent from riparian wells; and 1 mrem/yr effective dose equivalent from the watershed. Because the estimated doses are so small, the recommendation is that further work on the ground-water pathway be limited to tracking ongoing ground-water studies at the Hanford Site.

Freshley, M. D.; Thorne, P. D.

1992-01-01T23:59:59.000Z

410

RADIATION SENSITIVITY & PROCESSING OF DNA DAMAGE FOLLOWING LOW DOSES OF GAMMA-RAY ALPHA PARTICLES & HZE IRRADIATION OF NORMAL DSB REPAIR DEFICIENT CELLS  

SciTech Connect

Non-homologous end joining (NHEJ) predominates in the repair of DNA double strand breaks (DSB) over homologous recombination (HR). NHEJ occurs throughout the cell cycle whereas HR occurs in late S/G2 due to the requirement of a sister chromatid (Rothkamm et al, Mol Cell Biol 23 5706-15 [2003]). To date evidence obtained with DSB repair deficient cells using pulsed-field gel electrophoresis has revealed the major pathway throughout all phases of the cell cycle for processing high dose induced DSBs is NHEJ (Wang et al, Oncogene 20 2212-24 (2001); Pluth et al, Cancer Res. 61 2649-55 [2001]). These findings however were obtained at high doses when on average >> 20-30 DSBs are formed per cell. The contribution of the repair pathways (NHEJ and HR) induced in response to DNA damage during the various phases of the cell cycle may depend upon the dose (the level of initial DSBs) especially since low levels of DSBs are induced at low dose. To date, low dose studies using NHEJ and HR deficient mutants have not been carried out to address this important question with radiations of different quality. The work presented here leads us to suggest that HR plays a relatively minor role in the repair of radiation-induced prompt DSBs. SSBs lead to the induction of DSBs which are associated specifically with S-phase cells consistent with the idea that they are formed at stalled replication forks in which HR plays a major role in repair. That DNA-PKcs is in some way involved in the repair of the precursors to replication-induced DSB remains an open question. Persistent non-DSB oxidative damage also leads to an increase in RAD51 positive DSBs. Both simple and complex non-DSB DNA damage may therefore contribute to indirect DSBs induced by ionising radiation at replication forks.

O'Neil, Peter

2009-05-15T23:59:59.000Z

411

EFFECT OF TUBE CURRENT MODULATION FOR DOSE ESTIMATION USING A SIMULATION TOOL ON BODY CT EXAMINATION  

Science Journals Connector (OSTI)

......equivalent dose and w R is the radiation-weighting factor. F TCM, which represents the bone marrow, skin, bone surface, brain and salivary glands, was assumed to be 1.0 because the tube current could not be read for each region. The D TCM value of......

Ai Kawaguchi; Yuta Matsunaga; Masanao Kobayashi; Shoichi Suzuki; Kosuke Matsubara; Koichi Chida

2014-11-01T23:59:59.000Z

412

The Feasibility of Establishing a De Minimis Level of Radiation Dose and a Regulatory Cutoff Policy for Nuclear Regulation  

Science Journals Connector (OSTI)

This report discusses the feasibility of a de minimis policy for radiation exposure guidance and regulation. This policy would establish a threshold below which regulation of radiation sources, practices, or e...

Joyce P. Davis

1987-01-01T23:59:59.000Z

413

Relation between clinical and laboratory parameters with radiation dose rates from patients receiving iodine-131 therapy for thyroid carcinoma  

Science Journals Connector (OSTI)

......educate every patient on radiation safety procedures for the dosage...improvised containers; the safety officer transferred...origin of emission, and radiation detection survey metre...significant. SPSS for Windows software package (Release 11......

Isa Neshandar Asli; Nastaran Baharfard; Babak Shafiei; Faraj Tabei; Hamid Javadi; Mohammad Seyedabadi; Iraj Nabipour; Majid Assadi

2010-03-01T23:59:59.000Z

414

RET/PTC Rearrangements Preferentially Occurred in Papillary Thyroid Cancer among Atomic Bomb Survivors Exposed to High Radiation Dose  

Science Journals Connector (OSTI)

...Molecular Epidemiology, Radiation Effects Research Foundation...Hiroshima 732-0815, Japan. Phone: 81-82-261-3169...an important role in radiation-associated thyroid...Molecular Epidemiology, Radiation Effects Research Foundation...Hiroshima 732-0815, Japan. hamatani@rerf...

Kiyohiro Hamatani; Hidetaka Eguchi; Reiko Ito; Mayumi Mukai; Keiko Takahashi; Masataka Taga; Kazue Imai; John Cologne; Midori Soda; Koji Arihiro; Megumu Fujihara; Kuniko Abe; Tomayoshi Hayashi; Masahiro Nakashima; Ichiro Sekine; Wataru Yasui; Yuzo Hayashi; and Kei Nakachi

2008-09-01T23:59:59.000Z

415

Potential dose distributions at proposed surface radioactvity clearance levels resulting from occupational scenarios.  

SciTech Connect

The purpose of this report is to evaluate the potential dose distribution resulting from surface radioactivity, using occupational radiation exposure scenarios. The surface radioactivity clearance values considered in this analysis may ultimately replace those currently specified in the U.S. Department of Energy (DOE) requirements and guidance for radiological protection of workers, the public and the environment. The surface contamination values apply to radioactive contamination deposited on a surface (i.e., not incorporated into the interior of the material). For these calculations, the dose coefficients for intake of radionuclides were taken from ICRP Publication 68 (ICRP 1994), and external exposure dose coefficients were taken from the compact disc (CD) that accompanied Federal Guidance Report (FGR) 13 (Eckerman et al. 1999). The ICRP Publication 68 dose coefficients were based on ICRP Publication 60 (ICRP 1990) and were used specifically for worker dose calculations. The calculated dose in this analysis is the 'effective dose' (ED), rather than the 'effective dose equivalent' (EDE).

Kamboj, S.; Yu, C.; Rabovsky, J. (Environmental Science Division); (USDOE)

2011-08-02T23:59:59.000Z

416

Ionizing radiation dosimetry in the absorbed dose range 0.0150 \\{MGy\\} based on resistance and ESR linewidth measurements of organic conducting crystals  

Science Journals Connector (OSTI)

The materials studied in the present work as high-dose dosimeters are members of a large class of molecular crystals which are organic conductors of electricity. Very different from each other in the details of their molecular and crystal structures, they all behave in the same way when subjected to increasing high doses of radiation, at least from the point of view of their electronic transport properties, because of the quasi-one-dimensional character of the conduction process. Their resistivities increase exponentially with the absorbed dose while their electron spin resonance (ESR) linewidths decrease exponentially. Very small single crystals less than 10 ?m thick can be used as dosimeters in the dose range 0.0150 \\{MGy\\} for ? rays as well as for electron irradiations, by applying four probe resistance measurements. Only a few compounds over a large number of candidates have been irradiated in the present work with ?-rays, low energy x-rays and electrons. In some favourable cases the energy and temperature dependences of the dosimeters have been checked experimentally. Their mass energy absorption coefficients and electron stopping powers have been also calculated. It is hoped to extend this kind of dosimetry to lower and higher doses by trying new compounds from the large family of organic conductors or by improving the resistivity and ESR measurement techniques.

L. Zuppiroli; S. Bouffard; J.J. Jacob

1985-01-01T23:59:59.000Z

417

Colour and lipid oxidation changes in dry-cured loins from free-range reared and intensively reared pigs as affected by ionizing radiation dose level  

Science Journals Connector (OSTI)

The effect of irradiation (0, 5 and 10 kGy) of vacuum-packaged Iberian dry-cured loin slices from pigs fed on concentrate (CON) or free-range reared (FRG) was studied in relation to colour changes, TBA-RS and hexanal content. Both, ionizing radiation and type of loin had a significant effect on the instrumental colour parameters of the samples. Irradiation resulted in significantly higher a*-values in both sets of loins, indicating a redder colour. Numerically calculated total colour difference (?E) changes were significantly less intense in CON vacuum-packaged dry-cured loin slices than in FRG samples and changed significantly at 10 kGy dose levels in both types of samples. TBA-RS numbers were significantly affected by irradiation dose and type of loin and increased linearly with dose in both types of slices. Increments in TBA-RS numbers in FRG loin slices was dose-dependent and was closely related to the type of dry-cured loin. Irradiation of dry-cured loin slices significantly increased hexanal contents in both groups of loins and the increases were dose-dependent and greater in FRG samples than in CON samples. Differences in the characteristics of the raw material and initial lipid oxidation level could play an important role in the irradiation-induced changes in vacuum-packaged dry-cured loin slices.

A. Carrasco; R. Trrega; M.R. Ramrez; F.J. Mingoarranz; R. Cava

2005-01-01T23:59:59.000Z

418

Radiation dose to the internal pudendal arteries from permanent-seed prostate brachytherapy as determined by time-of-flight MR angiography  

SciTech Connect

Purpose: To determine the feasibility of time-of-flight magnetic resonance (MR) angiography to visualize the internal pudendal arteries (IPAs) in potent men undergoing permanent-seed prostate brachytherapy and to calculate the radiation dose received by these arteries. Methods and Materials: Prostate brachytherapy is performed at the University Health Network/Princess Margaret Hospital by use of transrectal ultrasound (TRUS) preplanning and preloaded needles. All patients received {sup 125}I, with a mean seed activity of 0.32 mCi/seed (0.41 U). Postplan evaluation is performed at 1 month by magnetic resonance-computed tomography fusion. Twenty consecutive potent men had time-of-flight MR angiography as part of their postplan evaluation. Results: The mean V100 was 96.5%, and the mean D90 was171.5 Gy. The IPAs were easily visualized for 18 of the 20 men. The mean peak dose received by the IPA was 17 Gy. The highest peak dose received by any patient was 38.2 Gy, with only 1 other patient receiving a peak dose greater than 30 Gy. Eleven of 18 had a measurable portion of at least 1 IPA that received 10% of the prescribed dose (V10 = 14.5 Gy). Only 2 patients had nonzero values for V25. The distal third of the IPA received the highest dose for 16 of the 18 patients. Conclusions: The IPAs can be well visualized in the majority of potent men by use of time-of-flight MR angiography 1 month after brachytherapy. The IPAs receive a low but calculable dose from permanent-seed {sup 125}I brachytherapy. Further research is needed to determine if this outcome has any correlation with subsequent potency.

Gillan, Caitlin [Department of Radiation Medicine, University Health Network, Princess Margaret Hospital, Toronto (Canada); Kirilova, Anna [Department of Radiation Physics, University Health Network, Princess Margaret Hospital, Toronto (Canada); Landon, Angela [Department of Radiation Medicine, University Health Network, Princess Margaret Hospital, Toronto (Canada); Yeung, Ivan [Department of Radiation Physics, University Health Network, Princess Margaret Hospital, Toronto (Canada); Pond, Gregory [Department of Biostatistics, University Health Network, Princess Margaret Hospital, Toronto (Canada); Crook, Juanita [Department of Radiation Oncology, University Health Network, Princess Margaret Hospital, Toronto (Canada)]. E-mail: juanita.crook@rmp.uhn.on.ca

2006-07-01T23:59:59.000Z

419

High-Dose and Extended-Field Intensity Modulated Radiation Therapy for Early-Stage NK/T-Cell Lymphoma of Waldeyer's Ring: Dosimetric Analysis and Clinical Outcome  

SciTech Connect

Purpose: To assess the dosimetric benefit, treatment outcome, and toxicity of high-dose and extended-field intensity modulated radiation therapy (IMRT) in patients with early-stage NK/T-cell lymphoma of Waldeyer's ring (WR-NKTCL). Methods and Materials: Thirty patients with early-stage WR-NKTCL who received extended-field IMRT were retrospectively reviewed. The prescribed dose was 50 Gy to the primary involved regions and positive cervical lymph nodes (planning target volume requiring radical irradiation [PTV{sub 50}]) and 40 Gy to the negative cervical nodes (PTV{sub 40}). Dosimetric parameters for the target volume and critical normal structures were evaluated. Locoregional control (LRC), overall survival (OS), and progression-free survival (PFS) were calculated using the Kaplan-Meier method. Results: The median mean doses to the PTV{sub 50} and PTV{sub 40} were 53.2 Gy and 43.0 Gy, respectively. Only 1.4% of the PTV{sub 50} and 0.9% of the PTV{sub 40} received less than 95% of the prescribed dose, indicating excellent target coverage. The average mean doses to the left and right parotid glands were 27.7 and 28.4 Gy, respectively. The 2-year OS, PFS, and LRC rates were 71.2%, 57.4%, and 87.8%. Most acute toxicities were grade 1 to 2, except for grade ?3 dysphagia and mucositis. The most common late toxicity was grade 1-2 xerostomia, and no patient developed any ?grade 3 late toxicities. A correlation between the mean dose to the parotid glands and the degree of late xerostomia was observed. Conclusions: IMRT achieves excellent target coverage and dose conformity, as well as favorable survival and locoregional control rates with acceptable toxicities in patients with WR-NKTCL.

Bi, Xi-Wen; Li, Ye-Xiong, E-mail: yexiong@yahoo.com; Fang, Hui; Jin, Jing; Wang, Wei-Hu; Wang, Shu-Lian; Liu, Yue-Ping; Song, Yong-Wen; Ren, Hua; Dai, Jian-Rong

2013-12-01T23:59:59.000Z

420

About Radiation  

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

Radiation Radiation What is radiation? Radiation is a form of energy that is a part of our everyday lives. All of us receive a "dose" of radiation each day. Most of the dose comes from naturally occurring radioactive materials such as uranium, thorium, radon, and certain forms of potassium and carbon. The air we breathe contains radon, the food we eat contains uranium and thorium from the soil, and our bodies contain radioactive forms of potassium and carbon. Cosmic radiation from the sun also contributes to our natural radiation dose. We also receive radiation doses from man-made sources such as X-rays, nuclear medical procedures, power plants, smoke detectors and older television sets. Some people, such as nuclear plant operators, flight crews, and nuclear medicine staff may also receive an occupational radiation dose.

Note: This page contains sample records for the topic "radiation dose equivalent" 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.