Sample records for radiation dose ranges

  1. Radiation protection instrumentation - ambient and/or directional dose equivalent (rate) meters and/or monitors for beta, X and gamma radiation part 2: high range beta and photon dose and dose rate portable instruments for emergency radiation protection purposes

    E-Print Network [OSTI]

    International Electrotechnical Commission. Geneva

    2007-01-01T23:59:59.000Z

    Radiation protection instrumentation - ambient and/or directional dose equivalent (rate) meters and/or monitors for beta, X and gamma radiation

  2. SCIENTIFIC CORRESPONDENCE Radiation doses

    E-Print Network [OSTI]

    Shlyakhter, Ilya

    -- ation doses and cancer rates to the workers m the first Soviet atom-bomb facility, near 2 Chelyabinsk

  3. Low-dose radiation impacts skin sensitivity | EMSL

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

    Low-dose radiation impacts skin sensitivity Low-dose radiation impacts skin sensitivity Released: April 06, 2015 Systems approach suggests alterations in stability of cells and...

  4. Radiation Leukemogenesis at Low Dose Rates

    SciTech Connect (OSTI)

    Weil, Michael; Ullrich, Robert

    2013-09-25T23:59:59.000Z

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

  5. Agriculture-related radiation dose calculations

    SciTech Connect (OSTI)

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

    1987-10-01T23:59:59.000Z

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

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

    E-Print Network [OSTI]

    Brenner, David Jonathan

    risk; National Council on Radiation Protection and Measurements INTRODUCTION THERE IS considerablePaper EXTRAPOLATING RADIATION-INDUCED CANCER RISKS FROM LOW DOSES TO VERY LOW DOSES David J. Brenner* Abstract--There is strong evidence that ionizing radiation increases cancer risks at high doses

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

    SciTech Connect (OSTI)

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

    1991-12-31T23:59:59.000Z

    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.

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

    SciTech Connect (OSTI)

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

    2012-11-01T23:59:59.000Z

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

  9. Intensity Modulated Beam Radiation Therapy Dose Optimization with Multiobjective

    E-Print Network [OSTI]

    Coello, Carlos A. Coello

    Intensity Modulated Beam Radiation Therapy Dose Optimization with Multiobjective Evolutionary will be di- agnosed with cancer. Half of these will be treated with radiation therapy [1]. In teletherapy or external radiotherapy beams of penetrating radiation are directed at the tumor. Along their path through

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

    SciTech Connect (OSTI)

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

    2013-12-01T23:59:59.000Z

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

  11. Progress in high-dose radiation dosimetry. Final report

    SciTech Connect (OSTI)

    Ettinger, K.V.; Nam, J.W.; McLaughlin, W.L.; Chadwick, K.H.

    1981-01-01T23:59:59.000Z

    The last decade has witnessed a deluge of new high-dose dosimetry techniques and expended applications of methods developed earlier. Many of the principal systems are calibrated by means of calorimetry, although production of heat is not always the final radiation effect of interest. Requirements for a stable and reliable transfer dose meters have led to further developments of several important high-dose systems: thermoluminescent materials, radiochromic dyes, ceric-cerous solutions analyzed by high-frequency oscillometry. A number of other prospective dosimeters are also treated in this review. In addition, an IAEA program of high-dose intercomparison and standardization for industrial radiation processing is described.

  12. Progress in high-dose radiation dosimetry. Final report

    SciTech Connect (OSTI)

    Ettinger, K.V.; Nam, J.W.; McLaughlin, W.L.; Chadwick, K.H.

    1981-01-01T23:59:59.000Z

    The last decade has witnessed a deluge of new high-dose dosimetry techniques and expended applications of methods developed earlier. Many of the principal systems are calibrated by means of calorimetry, although production of heat is not always the final radiation effect of interest. Requirements for a stable and reliable transfer dose meters have led to further developments of several important high-dose systems: thermoluminescent materials, radiochromic dyes, ceric-cerous solutions analyzed by high-frequency oscillometry. A number of other prospective dosimeters also treated in this review. In addition, an IAEA programme of high-dose intercomparison and standardization for industrial radiation processing is described.

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

    SciTech Connect (OSTI)

    Kleiman, Norman Jay [Columbia University] [Columbia University

    2013-11-30T23:59:59.000Z

    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.

  14. ORISE: Radiation Dose Estimates and Other Compendia

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of Science (SC)Integrated CodesTransparencyDOENurse Triage LinesCytogeneticHowResponseDose Estimates

  15. Biological dosimetry - the use of hematological variables in the estimation of radiation dose

    E-Print Network [OSTI]

    Barranco, Samuel Christopher

    1962-01-01T23:59:59.000Z

    of 103 roentgens per hour by a Co" source, operated by the Agricultural and Mechanical College of Texas. They received doses ranging from 0 r to 685 r at graduated increments of 13'I r . A complete hematology picture was obtained on each rat... itself [Sheedy, 1962]. A survey of the literature concerning radiation accidents [Wald and Thoma, 1961] reveals that exposures to less than 100 r rarely result in clinical symptomology; hence, for our present purposes the radiation syndrome [certain...

  16. An evaluation of theories concerning the health effects of low-dose radiation exposures

    E-Print Network [OSTI]

    Wei, Elizabeth J. (Elizabeth Jay)

    2012-01-01T23:59:59.000Z

    The danger of high, acute doses of radiation is well documented, but the effects of low-dose radiation below 100 mSv is still heavily debated. Four theories concerning the effects of lowdose radiation are presented here: ...

  17. Calculation of radiation therapy dose using all particle Monte Carlo transport

    DOE Patents [OSTI]

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

    1999-01-01T23:59:59.000Z

    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.

  18. Calculation of radiation therapy dose using all particle Monte Carlo transport

    DOE Patents [OSTI]

    Chandler, W.P.; Hartmann-Siantar, C.L.; Rathkopf, J.A.

    1999-02-09T23:59:59.000Z

    The actual radiation dose absorbed in the body is calculated using three-dimensional Monte Carlo transport. Neutrons, protons, deuterons, tritons, helium-3, alpha particles, photons, electrons, and positrons are transported in a completely coupled manner, using this Monte Carlo All-Particle Method (MCAPM). The major elements of the invention include: computer hardware, user description of the patient, description of the radiation source, physical databases, Monte Carlo transport, and output of dose distributions. This facilitated the estimation of dose distributions on a Cartesian grid for neutrons, photons, electrons, positrons, and heavy charged-particles incident on any biological target, with resolutions ranging from microns to centimeters. Calculations can be extended to estimate dose distributions on general-geometry (non-Cartesian) grids for biological and/or non-biological media. 57 figs.

  19. Staff Radiation Doses in a Real-Time Display Inside the Angiography Room

    SciTech Connect (OSTI)

    Sanchez, Roberto, E-mail: rmsanchez.hcsc@salud.madrid.org; Vano, E.; Fernandez, J. M. [Hospital Clinico San Carlos, Medical Physics Department (Spain); Gallego, J. J. [Universidad Complutense de Madrid, Radiology Department (Spain)

    2010-12-15T23:59:59.000Z

    MethodsThe evaluation of a new occupational Dose Aware System (DAS) showing staff radiation doses in real time has been carried out in several angiography rooms in our hospital. The system uses electronic solid-state detectors with high-capacity memory storage. Every second, it archives the dose and dose rate measured and is wirelessly linked to a base-station screen mounted close to the diagnostic monitors. An easy transfer of the values to a data sheet permits further analysis of the scatter dose profile measured during the procedure, compares it with patient doses, and seeks to find the most effective actions to reduce operator exposure to radiation.ResultsThe cumulative occupational doses measured per procedure (shoulder-over lead apron) ranged from 0.6 to 350 {mu}Sv when the ceiling-suspended screen was used, and DSA (Digital Subtraction Acquisition) runs were acquired while the personnel left the angiography room. When the suspended screen was not used and radiologists remained inside the angiography room during DSA acquisitions, the dose rates registered at the operator's position reached up to 1-5 mSv/h during fluoroscopy and 12-235 mSv/h during DSA acquisitions. In such case, the cumulative scatter dose could be more than 3 mSv per procedure.ConclusionReal-time display of doses to staff members warns interventionists whenever the scatter dose rates are too high or the radiation protection tools are not being properly used, providing an opportunity to improve personal protection accordingly.

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

    E-Print Network [OSTI]

    Brenner, David Jonathan

    of the radiation risks they are trying to control. Ã? 2012 ICRP. Published by Elsevier Ltd. All rights reserved Effective dose (ICRP, 1977) represents an attempt to provide a quantity which is proportional of the International Commission on Radiological Protection. 124 #12;and hereditary effects. Specifically, it is the sum

  1. Low dose ionizing radiation detection using conjugated polymers

    SciTech Connect (OSTI)

    Silva, E.A.B.; Borin, J.F.; Nicolucci, P.; Graeff, C.F.O.; Netto, T. Ghilardi; Bianchi, R.F. [Departamento de Fisica e Matematica, FFCLRP, Universidade de Sao Paulo, Av. Bandeirantes 3900, 14040-901 Ribeirao Preto, SP (Brazil); Centro de Cie circumflex ncias das Imagens e Fisica Medica, Hospital das Clinicas, FMRP, Universidade de Sao Paulo, Av. Bandeirantes 3900, 14040-901 Ribeirao Preto, SP (Brazil); Departamento de Engenharia de Sistemas Integraveis, Escola Politecnica da Universidade de Sao Paulo, Av. Prof. Luciano Gualberto, 158, Sao Paulo, SP (Brazil)

    2005-03-28T23:59:59.000Z

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

  2. Radiation Dose and Subsequent Risk for Stomach Cancer in Long-term Survivors of Cervical Cancer

    SciTech Connect (OSTI)

    Kleinerman, Ruth A., E-mail: kleinerr@mail.nih.gov [Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, US Department of Health and Human Services, Rockville, Maryland (United States); Smith, Susan A. [Department of Radiation Physics, University of Texas M D Anderson Cancer Center, Houston, Texas (United States); Holowaty, Eric [Dalla Lana School of Public Health, University of Toronto, Toronto, Ontario (Canada); Hall, Per [Department of Medical Epidemiology and Biostatistics, Karolinska Institute, Stockholm (Sweden); Pukkala, Eero [Finnish Cancer Registry, Institute for Statistical and Epidemiological Cancer Research, Helsinki (Finland); Vaalavirta, Leila [Department of Oncology, Helsinki University Central Hospital, Helsinki (Finland); Stovall, Marilyn; Weathers, Rita [Department of Radiation Physics, University of Texas M D Anderson Cancer Center, Houston, Texas (United States); Gilbert, Ethel [Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, US Department of Health and Human Services, Rockville, Maryland (United States); Aleman, Berthe M.P. [Department of Radiotherapy, The Netherlands Cancer Institute, Amsterdam (Netherlands); Kaijser, Magnus [Clinical Epidemiology Unit, Department of Medicine, Karolinska Institute, Stockholm (Sweden); Andersson, Michael [Department of Oncology, Copenhagen University Hospital, Copenhagen (Denmark); Storm, Hans [Cancer Prevention and Documentation, Danish Cancer Society, Copenhagen (Denmark); Joensuu, Heikki [Department of Oncology, Helsinki University Central Hospital, Helsinki (Finland); Lynch, Charles F. [Department of Epidemiology, University of Iowa, Iowa City, Iowa (United States); and others

    2013-08-01T23:59:59.000Z

    Purpose: To assess the dose–response relationship for stomach cancer after radiation therapy for cervical cancer. Methods and Materials: We conducted a nested, matched case–control study of 201 cases and 378 controls among 53,547 5-year survivors of cervical cancer diagnosed from 1943 to 1995, from 5 international, population-based cancer registries. We estimated individual radiation doses to the site of the stomach cancer for all cases and to corresponding sites for the matched controls (overall mean stomach tumor dose, 2.56 Gy, range 0.03-46.1 and after parallel opposed pelvic fields, 1.63 Gy, range 0.12-6.3). Results: More than 90% of women received radiation therapy, mostly with external beam therapy in combination with brachytherapy. Stomach cancer risk was nonsignificantly increased (odds ratio 1.27-2.28) for women receiving between 0.5 and 4.9 Gy to the stomach cancer site and significantly increased at doses ?5 Gy (odds ratio 4.20, 95% confidence interval 1.41-13.4, P{sub trend}=.047) compared with nonirradiated women. A highly significant radiation dose–response relationship was evident when analyses were restricted to the 131 cases (251 controls) whose stomach cancer was located in the middle and lower portions of the stomach (P{sub trend}=.003), whereas there was no indication of increasing risk with increasing dose for 30 cases (57 controls) whose cancer was located in the upper stomach (P{sub trend}=.23). Conclusions: Our findings show for the first time a significant linear dose–response relationship for risk of stomach cancer in long-term survivors of cervical cancer.

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

    E-Print Network [OSTI]

    Davidson, Matthew Allen

    2011-01-01T23:59:59.000Z

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

  4. Radiation dose fractionation studies with hypoxic cell radiosensitizers using a murine tumor. [X-ray; mice

    SciTech Connect (OSTI)

    Hill, R.P.

    1982-03-01T23:59:59.000Z

    The ability of five nitroimidazoles, metronidazole (MET), misonidazole (MISO), desmethymisonidazole (DMM), SR 2508 and SR 2555, to sensitize the KHT sarcoma to radiation treatment has been compared for drug doses in the range 0-1.5 g/Kg. Single radiation doses or two different daily fractionation schedules (4 fractions of 5 Gy each or 7 fraction of 3 Gy each) were used; the tumor cell survival was determined using either an in vivo or in vitro colony assay. Each radiation (100 kVp X rays at 11 Gy/min) treatment was given locally, 60-70 min (MET) or 30-40 min (other drugs) after either intraperitoneal (MET, MISO, DMM) or intraveous (SR 2508, SR 2555) injection of the drugs; these times have been shown to be optimum for this tumor. For the single doses and both fractionation schedules the tumor cell survival, following the irradiation treatment, declined as the drug dose increased in the range 0 to 0.75 g/Kg for all the drugs, but above this dose level a plateau was reached and the amount of sensitization remained essentially constant. In this plateau region the reduction in survival achieved was similar for single doses and 5 Gy fraction but was less for 3 Gy fractions, indicating that sensitization was smaller for the smaller dose fractions. For the 4 x 5 Gy fractionation schedule the plateau level of survival was lowest for MISO, DMM and SR 2508, slightly higher for SR 2555 and much higher for MET. For the 3 Gy fractions SR 2508 appeared slightly less effective than MISO and DMM.

  5. Estimated cumulative radiation dose from PET/CT in children with malignancies: reply to Gelfand et al

    E-Print Network [OSTI]

    Chawla, Soni C.; Boechat, M. Ines; McNitt-Gray, Michael

    2010-01-01T23:59:59.000Z

    radiation dose from PET/CT in children with malignancies.radiation dose from PET/CT in children with malig- nancies:radiation dose from PET/CT in children with malignancies:

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

    SciTech Connect (OSTI)

    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

    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.

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

    SciTech Connect (OSTI)

    Jurkovic, Slaven [Department of Radiotherapy and Oncology, University Hospital, Rijeka (Croatia)], E-mail: slaven.jurkovic@ri.htnet.hr; Zauhar, Gordana [Department of Physics, School of Medicine, Rijeka (Croatia); Faj, Dario [Department of Radiotherapy and Oncology, University Hospital, Osijek (Croatia); Radojcic, Deni Smilovic; Svabic, Manda [Department of Radiotherapy and Oncology, University Hospital, Rijeka (Croatia)

    2010-04-01T23:59:59.000Z

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

  8. Evaluation of Radiation Dose Effects on Rat Bones Using Synchrotron Radiation Computed Microtomography

    SciTech Connect (OSTI)

    Nogueira, Liebert Parreiras; Braz, Delson [Nuclear Instrumentation Laboratory / COPPE / UFRJ, P.O. Box 68509, 21945-970, Rio de Janeiro (Brazil); Barroso, Regina Cely [Physics Institute / State University of Rio de Janeiro, 20550-900, Rio de Janeiro (Brazil); Almeida, Carlos Eduardo de; Andrade, Cherley Borba [Laboratory of Radiological Sciences / State University of Rio de Janeiro, Rio de Janeiro (Brazil); Tromba, Giuliana [Sincrotrone Trieste SCpA, Strada Statale S.S. 14 km 163.5, 34012 Basovizza, Trieste (Italy)

    2011-12-13T23:59:59.000Z

    In this work, we investigated the consequences of irradiation in the femora and ribs of rats submitted to radiation doses of 5 Gy. Three different sites in femur specimens (head, distal metaphysis and distal epiphysis) and one in ribs (ventral) were imaged using synchrotron radiation microcomputed tomography to assess trabecular bone microarchitecture. Histomorphometric quantification was calculated directly from the 3D microtomographic images using synchrotron radiation. The 3D microtomographic images were obtained at the SYRMEP (SYnchrotron Radiation for MEdical Physics) beamline at the Elettra Synchrotron Laboratory in Trieste, Italy. A better understanding of the biological interactions that occur after exposure to photon radiation is needed in order to optimize therapeutic regimens and facilitate development and strategies that decrease radiation-induced side effects in humans. Results showed significant differences between irradiated and non-irradiated specimens, mostly in head and distal metaphysis bone sites.

  9. Nominal effective radiation doses delivered during clinical trials of boron neutron capture therapy

    SciTech Connect (OSTI)

    Capala, J.; Diaz, A.Z.; Chanana, A.D.

    1997-12-31T23:59:59.000Z

    Boron neutron capture therapy (BNCT) is a binary system that, in theory, should selectively deliver lethal, high linear energy transfer (LET) radiation to tumor cells dispersed within normal tissues. It is based on the nuclear reaction 10-B(n, {alpha})7-Li, which occurs when the stable nucleus of boron-10 captures a thermal neutron. Due to the relatively high cross-section of the 10-B nucleus for thermal neutron capture and short ranges of the products of this reaction, tumor cells in the volume exposed to thermal neutrons and containing sufficiently high concentration of 10-B would receive a much higher radiation dose than the normal cells contained within the exposed volume. Nevertheless, radiation dose deposited in normal tissue by gamma and fast neutron contamination of the neutron beam, as well as neutron capture in nitrogen, 14-N(n,p)14-C, hydrogen, 1-H(n,{gamma})2-H, and in boron present in blood and normal cells, limits the dose that can be delivered to tumor cells. It is, therefore, imperative for the success of the BNCT the dosed delivered to normal tissues be accurately determined in order to optimize the irradiation geometry and to limit the volume of normal tissue exposed to thermal neutrons. These are the major objectives of BNCT treatment planning.

  10. Dose Uncertainties in IMPT for Oropharyngeal Cancer in the Presence of Anatomical, Range, and Setup Errors

    SciTech Connect (OSTI)

    Kraan, Aafke C., E-mail: aafke.kraan@pi.infn.it [Erasmus MC Daniel den Hoed Cancer Center, Rotterdam (Netherlands); Water, Steven van de; Teguh, David N.; Al-Mamgani, Abrahim [Erasmus MC Daniel den Hoed Cancer Center, Rotterdam (Netherlands); Madden, Tom; Kooy, Hanne M. [Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts (United States); Heijmen, Ben J.M.; Hoogeman, Mischa S. [Erasmus MC Daniel den Hoed Cancer Center, Rotterdam (Netherlands)

    2013-12-01T23:59:59.000Z

    Purpose: Setup, range, and anatomical uncertainties influence the dose delivered with intensity modulated proton therapy (IMPT), but clinical quantification of these errors for oropharyngeal cancer is lacking. We quantified these factors and investigated treatment fidelity, that is, robustness, as influenced by adaptive planning and by applying more beam directions. Methods and Materials: We used an in-house treatment planning system with multicriteria optimization of pencil beam energies, directions, and weights to create treatment plans for 3-, 5-, and 7-beam directions for 10 oropharyngeal cancer patients. The dose prescription was a simultaneously integrated boost scheme, prescribing 66 Gy to primary tumor and positive neck levels (clinical target volume-66 Gy; CTV-66 Gy) and 54 Gy to elective neck levels (CTV-54 Gy). Doses were recalculated in 3700 simulations of setup, range, and anatomical uncertainties. Repeat computed tomography (CT) scans were used to evaluate an adaptive planning strategy using nonrigid registration for dose accumulation. Results: For the recalculated 3-beam plans including all treatment uncertainty sources, only 69% (CTV-66 Gy) and 88% (CTV-54 Gy) of the simulations had a dose received by 98% of the target volume (D98%) >95% of the prescription dose. Doses to organs at risk (OARs) showed considerable spread around planned values. Causes for major deviations were mixed. Adaptive planning based on repeat imaging positively affected dose delivery accuracy: in the presence of the other errors, percentages of treatments with D98% >95% increased to 96% (CTV-66 Gy) and 100% (CTV-54 Gy). Plans with more beam directions were not more robust. Conclusions: For oropharyngeal cancer patients, treatment uncertainties can result in significant differences between planned and delivered IMPT doses. Given the mixed causes for major deviations, we advise repeat diagnostic CT scans during treatment, recalculation of the dose, and if required, adaptive planning to improve adequate IMPT dose delivery.

  11. absorbed radiation dose: Topics by E-print Network

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

    10 Absorbed dose in target cell nuclei and dose conversion coefficient of radon progeny Biology and Medicine Websites Summary: Absorbed dose in target cell nuclei and...

  12. Osteoradionecrosis and Radiation Dose to the Mandible in Patients With Oropharyngeal Cancer

    SciTech Connect (OSTI)

    Tsai, Chiaojung Jillian [Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States)] [Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Hofstede, Theresa M. [Department of Dental Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States)] [Department of Dental Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Sturgis, Erich M. [Department of Head and Neck Surgery, University of Texas MD Anderson Cancer Center, Houston, Texas (United States)] [Department of Head and Neck Surgery, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Garden, Adam S., E-mail: agarden@mdanderson.org [Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Lindberg, Mary E. [Department of Radiation Physics, University of Texas MD Anderson Cancer Center, Houston, Texas (United States)] [Department of Radiation Physics, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Wei Qingyi [Department of Epidemiology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States)] [Department of Epidemiology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Tucker, Susan L. [Department of Bioinformatics and Computational Biology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States)] [Department of Bioinformatics and Computational Biology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Dong Lei [Department of Radiation Physics, University of Texas MD Anderson Cancer Center, Houston, Texas (United States)] [Department of Radiation Physics, University of Texas MD Anderson Cancer Center, Houston, Texas (United States)

    2013-02-01T23:59:59.000Z

    Purpose: To determine the association between radiation doses delivered to the mandible and the occurrence of osteoradionecrosis (ORN). Methods and Materials: We reviewed the records of 402 oropharyngeal cancer patients with stage T1 or T2 disease treated with definitive radiation between January 2000 and October 2008 for the occurrence of ORN. Demographic and treatment variables were compared between patients with ORN and those without. To examine the dosimetric relationship further, a nested case-control comparison was performed. One to 2 ORN-free patients were selected to match each ORN patient by age, sex, radiation type, treatment year, and cancer subsite. Detailed radiation treatment plans for the ORN cases and matched controls were reviewed. Mann-Whitney test and conditional logistic regression were used to compare relative volumes of the mandible exposed to doses ranging from 10 Gy-60 Gy in 10-Gy increments. Results: In 30 patients (7.5%), ORN developed during a median follow-up time of 31 months, including 6 patients with grade 4 ORN that required major surgery. The median time to develop ORN was 8 months (range, 0-71 months). Detailed radiation treatment plans were available for 25 of the 30 ORN patients and 40 matched ORN-free patients. In the matched case-control analysis, there was a statistically significant difference between the volumes of mandible in the 2 groups receiving doses between 50 Gy (V50) and 60 Gy (V60). The most notable difference was seen at V50, with a P value of .02 in the multivariate model after adjustment for the matching variables and dental status (dentate or with extraction). Conclusions: V50 and V60 saw the most significant differences between the ORN group and the comparison group. Minimizing the percent mandibular volume exposed to 50 Gy may reduce ORN risk.

  13. Low dose radiation interations with the transformation growth factor (TGF)-beta pathway 

    E-Print Network [OSTI]

    Maslowski, Amy Jesse

    2009-05-15T23:59:59.000Z

    A major limiting factor for long-term, deep-space missions is the radiation dose to astronauts. Because the dose to the astronauts is a mixed field of low- and high-LET radiation, there is a need to understand the effects of both radiation types...

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

    E-Print Network [OSTI]

    Shen, Jun

    Whole-Body Biodistribution and Estimation of Radiation-Absorbed Doses of the Dopamine D1 Receptor and Behaviour, Monash University, Clayton, Victoria, Australia The present study estimated radiation of interest were drawn on compressed planar images of source organs that could be iden- tified. Radiation dose

  15. Low Dose Radiation Response Curves, Networks and Pathways in Human Lymphoblastoid Cells Exposed from 1 to 10 cGy of Acute Gamma Radiation

    SciTech Connect (OSTI)

    Wyrobek, A. J.; Manohar, C. F.; Nelson, D. O.; Furtado, M. R.; Bhattacharya, M. S.; Marchetti, F.; Coleman, M.A.

    2011-04-18T23:59:59.000Z

    We investigated the low dose dependency of the transcriptional response of human cells to characterize the shape and biological functions associated with the dose response curve and to identify common and conserved functions of low dose expressed genes across cells and tissues. Human lymphoblastoid (HL) cells from two unrelated individuals were exposed to graded doses of radiation spanning the range of 1-10 cGy were analyzed by transcriptome profiling, qPCR and bioinformatics, in comparison to sham irradiated samples. A set of {approx}80 genes showed consistent responses in both cell lines; these genes were associated with homeostasis mechanisms (e.g., membrane signaling, molecule transport), subcellular locations (e.g., Golgi, and endoplasmic reticulum), and involved diverse signal transduction pathways. The majority of radiation-modulated genes had plateau-like responses across 1-10 cGy, some with suggestive evidence that transcription was modulated at doses below 1 cGy. MYC, FOS and TP53 were the major network nodes of the low-dose response in HL cells. Comparison our low dose expression findings in HL cells with those of prior studies in mouse brain after whole body exposure, in human keratinocyte cultures, and in endothelial cells cultures, indicates that certain components of the low dose radiation response are broadly conserved across cell types and tissues, independent of proliferation status.

  16. Normal Liver Tissue Density Dose Response in Patients Treated With Stereotactic Body Radiation Therapy for Liver Metastases

    SciTech Connect (OSTI)

    Howells, Christopher C.; Stinauer, Michelle A.; Diot, Quentin; Westerly, David C.; Schefter, Tracey E.; Kavanagh, Brian D. [Department of Radiation Oncology, University of Colorado School of Medicine, Aurora, Colorado (United States)] [Department of Radiation Oncology, University of Colorado School of Medicine, Aurora, Colorado (United States); Miften, Moyed, E-mail: Moyed.Miften@ucdenver.edu [Department of Radiation Oncology, University of Colorado School of Medicine, Aurora, Colorado (United States)] [Department of Radiation Oncology, University of Colorado School of Medicine, Aurora, Colorado (United States)

    2012-11-01T23:59:59.000Z

    Purpose: To evaluate the temporal dose response of normal liver tissue for patients with liver metastases treated with stereotactic body radiation therapy (SBRT). Methods and Materials: Ninety-nine noncontrast follow-up computed tomography (CT) scans of 34 patients who received SBRT between 2004 and 2011 were retrospectively analyzed at a median of 8 months post-SBRT (range, 0.7-36 months). SBRT-induced normal liver tissue density changes in follow-up CT scans were evaluated at 2, 6, 10, 15, and 27 months. The dose distributions from planning CTs were mapped to follow-up CTs to relate the mean Hounsfield unit change ({Delta}HU) to dose received over the range 0-55 Gy in 3-5 fractions. An absolute density change of 7 HU was considered a significant radiographic change in normal liver tissue. Results: Increasing radiation dose was linearly correlated with lower post-SBRT liver tissue density (slope, -0.65 {Delta}HU/5 Gy). The threshold for significant change (-7 {Delta}HU) was observed in the range of 30-35 Gy. This effect did not vary significantly over the time intervals evaluated. Conclusions: SBRT induces a dose-dependent and relatively time-independent hypodense radiation reaction within normal liver tissue that is characterized by a decrease of >7 HU in liver density for doses >30-35 Gy.

  17. Optically erasable samarium-doped fluorophosphate glasses for high-dose measurements in microbeam radiation therapy

    SciTech Connect (OSTI)

    Morrell, B.; Okada, G.; Vahedi, S.; Koughia, C., E-mail: cyril.koughia@usask.ca; Kasap, S. O. [Department of Electrical and Computer Engineering, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5C9 (Canada); Edgar, A.; Varoy, C. [School of Chemical and Physical Sciences and MacDiarmid Institute, Victoria University of Wellington, Wellington 6140 (New Zealand); Belev, G.; Wysokinski, T.; Chapman, D. [Canadian Light Source, Inc., University of Saskatchewan, Saskatoon, Saskatchewan S7N 5C9 (Canada); Sammynaiken, R. [Saskatchewan Structural Sciences Centre, University of Saskatchewan, 110 Science Place, Saskatoon, Saskatchewan S7N 5C9 (Canada)

    2014-02-14T23:59:59.000Z

    Previous work has demonstrated that fluorophosphate (FP) glasses doped with trivalent samarium (Sm{sup 3+}) can be used as a dosimetric detector in microbeam radiation therapy (MRT) to measure high radiation doses and large dose variations with a resolution in the micrometer range. The present work addresses the use of intense optical radiation at 405?nm to erase the recorded dose information in Sm{sup 3+}-doped FP glass plates and examines the underlying physics. We have evaluated both the conversion and optical erasure of Sm{sup 3+}-doped FP glasses using synchrotron-generated high-dose x-rays at the Canadian Light Source. The Sm-ion valency conversion is accompanied by the appearance of x-ray induced optical absorbance due to the trapping of holes and electrons into phosphorus-oxygen hole (POHC) and electron (POEC) capture centers. Nearly complete Sm{sup 2+} to Sm{sup 3+} reconversion (erasure) may be achieved by intense optical illumination. Combined analysis of absorbance and electron spin resonance measurements indicates that the optical illumination causes partial disappearance of the POHC and the appearance of new POEC. The suggested model for the observed phenomena is based on the release of electrons during the Sm{sup 2+} to Sm{sup 3+} reconversion process, the capture of these electrons by POHC (and hence their disappearance), or by PO groups, with the appearance of new and/or additional POEC. Optical erasure may be used as a practical means to erase the recorded data and permits the reuse of these Sm-doped FP glasses in monitoring dose in MRT.

  18. Radiation Dose to the Esophagus From Breast Cancer Radiation Therapy, 1943-1996: An International Population-Based Study of 414 Patients

    SciTech Connect (OSTI)

    Lamart, Stephanie, E-mail: stephanie.lamart@nih.gov [Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Bethesda, Maryland (United States)] [Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Bethesda, Maryland (United States); Stovall, Marilyn [Department of Radiation Physics, University of Texas MD Anderson Cancer Center, Houston, Texas (United States)] [Department of Radiation Physics, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Simon, Steven L. [Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Bethesda, Maryland (United States)] [Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Bethesda, Maryland (United States); Smith, Susan A.; Weathers, Rita E.; Howell, Rebecca M. [Department of Radiation Physics, University of Texas MD Anderson Cancer Center, Houston, Texas (United States)] [Department of Radiation Physics, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Curtis, Rochelle E. [Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Bethesda, Maryland (United States)] [Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Bethesda, Maryland (United States); Aleman, Berthe M.P. [Department of Radiotherapy, The Netherlands Cancer Institute, Amsterdam (Netherlands)] [Department of Radiotherapy, The Netherlands Cancer Institute, Amsterdam (Netherlands); Travis, Lois [Rubin Center for Cancer Survivorship and Department of Radiation Oncology, University of Rochester Medical Center, Rochester, New York (United States)] [Rubin Center for Cancer Survivorship and Department of Radiation Oncology, University of Rochester Medical Center, Rochester, New York (United States); Kwon, Deukwoo [Sylvester Comprehensive Cancer Center, University of Miami, Miami, Florida (United States)] [Sylvester Comprehensive Cancer Center, University of Miami, Miami, Florida (United States); Morton, Lindsay M. [Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Bethesda, Maryland (United States)] [Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Bethesda, Maryland (United States)

    2013-07-15T23:59:59.000Z

    Purpose: To provide dosimetric data for an epidemiologic study on the risk of second primary esophageal cancer among breast cancer survivors, by reconstructing the radiation dose incidentally delivered to the esophagus of 414 women treated with radiation therapy for breast cancer during 1943-1996 in North America and Europe. Methods and Materials: We abstracted the radiation therapy treatment parameters from each patient’s radiation therapy record. Treatment fields included direct chest wall (37% of patients), medial and lateral tangentials (45%), supraclavicular (SCV, 64%), internal mammary (IM, 44%), SCV and IM together (16%), axillary (52%), and breast/chest wall boosts (7%). The beam types used were {sup 60}Co (45% of fields), orthovoltage (33%), megavoltage photons (11%), and electrons (10%). The population median prescribed dose to the target volume ranged from 21 Gy to 40 Gy. We reconstructed the doses over the length of the esophagus using abstracted patient data, water phantom measurements, and a computational model of the human body. Results: Fields that treated the SCV and/or IM lymph nodes were used for 85% of the patients and delivered the highest doses within 3 regions of the esophagus: cervical (population median 38 Gy), upper thoracic (32 Gy), and middle thoracic (25 Gy). Other fields (direct chest wall, tangential, and axillary) contributed substantially lower doses (approximately 2 Gy). The cervical to middle thoracic esophagus received the highest dose because of its close proximity to the SCV and IM fields and less overlying tissue in that part of the chest. The location of the SCV field border relative to the midline was one of the most important determinants of the dose to the esophagus. Conclusions: Breast cancer patients in this study received relatively high incidental radiation therapy doses to the esophagus when the SCV and/or IM lymph nodes were treated, whereas direct chest wall, tangentials, and axillary fields contributed lower doses.

  19. Environmental Radiation Dose Reconstruction for U.S. and Russian Weapons Production Facilities: Hanford and Mayak

    SciTech Connect (OSTI)

    Ansbaugh, Lynn R.; Degteva, M. O.; Kozheurov, V. P.; Napier, Bruce A.; Tolstykh, E. I.; Vorobiova, M. I.

    2003-05-01T23:59:59.000Z

    Another way to look at Cold War legacies is to examine the major environmental releases that resulted from past operation of Cold War-related facilities for the manufacture of nuclear weapons. Examining these historical releases and the resultant radiation dose to individuals living near these facilities is called environmental dose reconstruction. Dose reconstructions have been performed or are underway at most large Cold War installations in the United States, such as the Hanford facility; several are also underway in other countries, such as at the Mayak facility in Russia. The efforts in the United States are mostly based on historical operating records and current conditions, which are used to estimate environmental releases, transport, and human exposure. The Russian efforts are largely based on environmental measurements and measurements of human subjects; environmental transport modelling, when conducted, is used to organize and validate the measurements. Past operation of Cold War-related facilities for the manufacture of nuclear weapons has resulted in major releases of radionuclides into the environment. Reconstruction of the historical releases and the resultant radiation dose to individuals in the public living near these facilities is called environmental dose reconstruction. Dose reconstructions have been performed or are underway at most large Cold War installations in the United States; several are also underway in other countries. The types of activity performed, the operating histories, and the radionuclide releases vary widely across the different facilities. The U.S. Hanford Site and the Russian Mayak Production Association are used here to illustrate the nature of the assessed problems and the range of approaches developed to solve them.

  20. Spatial and dose–response analysis of fibrotic lung changes after stereotactic body radiation therapy

    SciTech Connect (OSTI)

    Vinogradskiy, Yevegeniy; Diot, Quentin; Kavanagh, Brian; Schefter, Tracey; Gaspar, Laurie; Miften, Moyed [Department of Radiation Oncology, University of Colorado School of Medicine, Aurora, Colorado 80045 (United States)] [Department of Radiation Oncology, University of Colorado School of Medicine, Aurora, Colorado 80045 (United States)

    2013-08-15T23:59:59.000Z

    Purpose: Stereotactic body radiation therapy (SBRT) is becoming the standard of care for early stage nonoperable lung cancers. Accurate dose–response modeling is challenging for SBRT because of the decreased number of clinical toxicity events. As a surrogate for a clinical toxicity endpoint, studies have proposed to use radiographic changes in follow up computed tomography (CT) scans to evaluate lung SBRT normal tissue effects. The purpose of the current study was to use local fibrotic lung regions to spatially and dosimetrically evaluate lung changes in patients that underwent SBRT.Methods: Forty seven SBRT patients treated at our institution from 2003 to 2009 were used for the current study. Our patient cohort had a total of 148 follow up CT scans ranging from 3 to 48 months post-therapy. Post-treatment scans were binned into intervals of 3, 6, 12, 18, 24, 30, and 36 months after the completion of treatment. Deformable image registration was used to align the follow up CT scans with the pretreatment CT and dose distribution. Areas of visible fibrotic changes were contoured. The centroid of each gross tumor volume (GTV) and contoured fibrosis volume was calculated and the fibrosis volume location and movement (magnitude and direction) relative to the GTV and 30 Gy isodose centroid were analyzed. To perform a dose–response analysis, each voxel in the fibrosis volume was sorted into 10 Gy dose bins and the average CT number value for each dose bin was calculated. Dose–response curves were generated by plotting the CT number as a function of dose bin and time posttherapy.Results: Both fibrosis and GTV centroids were concentrated in the upper third of the lung. The average radial movement of fibrosis centroids relative to the GTV centroids was 2.6 cm with movement greater than 5 cm occurring in 11% of patients. Evaluating dose–response curves revealed an overall trend of increasing CT number as a function of dose. The authors observed a CT number plateau at doses ranging from 30 to 50 Gy for the 3, 6, and 12 months posttherapy time points. There was no evident plateau for the dose–response curves generated using data from the 18, 24, 30, and 36 months posttherapy time points.Conclusions: Regions of local fibrotic lung changes in patients that underwent SBRT were evaluated spatially and dosimetrically. The authors found that the average fibrosis movement was 2.6 cm with movement greater than 5 cm possible. Evaluating dose–response curves revealed an overall trend of increasing CT number as a function of dose. Furthermore, our dose–response data also suggest that one of the possible explanations of the CT number plateau effect may be the time posttherapy of the acquired data. Understanding normal tissue dose–response is important for reducing toxicity after SBRT, especially in cases where larger tumors are treated. The methods presented in the current work build on prior quantitative studies and further enhance the understanding of normal lung dose–response after SBRT.

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

    SciTech Connect (OSTI)

    Steer, Anna N. [Department of Radiation Oncology, North Coast Cancer Institute, Coffs Harbour (Australia)] [Department of Radiation Oncology, North Coast Cancer Institute, Coffs Harbour (Australia); Aherne, Noel J., E-mail: noel.aherne@ncahs.health.nsw.gov.au [Department of Radiation Oncology, North Coast Cancer Institute, Coffs Harbour (Australia); Rural Clinical School Faculty of Medicine, University of New South Wales, Coffs Harbour (Australia); Gorzynska, Karen; Hoffman, Matthew; Last, Andrew; Hill, Jacques [Department of Radiation Oncology, North Coast Cancer Institute, Coffs Harbour (Australia)] [Department of Radiation Oncology, North Coast Cancer Institute, Coffs Harbour (Australia); Shakespeare, Thomas P. [Department of Radiation Oncology, North Coast Cancer Institute, Coffs Harbour (Australia) [Department of Radiation Oncology, North Coast Cancer Institute, Coffs Harbour (Australia); Rural Clinical School Faculty of Medicine, University of New South Wales, Coffs Harbour (Australia)

    2013-07-15T23:59:59.000Z

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

  2. Estimation of Internal Radiation Dose from both Immediate Releases and Continued Exposures to Contaminated Materials

    SciTech Connect (OSTI)

    Napier, Bruce A.

    2012-03-26T23:59:59.000Z

    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, is discussed based upon 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 the damaged reactors and also to the management of wastes that may be generated in both regional cleanup and NPP decommissioning.

  3. Second Solid Cancers After Radiation Therapy: A Systematic Review of the Epidemiologic Studies of the Radiation Dose-Response Relationship

    SciTech Connect (OSTI)

    Berrington de Gonzalez, Amy, E-mail: berringtona@mail.nih.gov [Radiation Epidemiology Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Bethesda, Maryland (United States); Gilbert, Ethel; Curtis, Rochelle; Inskip, Peter; Kleinerman, Ruth; Morton, Lindsay; Rajaraman, Preetha; Little, Mark P. [Radiation Epidemiology Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Bethesda, Maryland (United States)] [Radiation Epidemiology Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Bethesda, Maryland (United States)

    2013-06-01T23:59:59.000Z

    Rapid innovations in radiation therapy techniques have resulted in an urgent need for risk projection models for second cancer risks from high-dose radiation exposure, because direct observation of the late effects of newer treatments will require patient follow-up for a decade or more. However, the patterns of cancer risk after fractionated high-dose radiation are much less well understood than those after lower-dose exposures (0.1-5 Gy). In particular, there is uncertainty about the shape of the dose-response curve at high doses and about the magnitude of the second cancer risk per unit dose. We reviewed the available evidence from epidemiologic studies of second solid cancers in organs that received high-dose exposure (>5 Gy) from radiation therapy where dose-response curves were estimated from individual organ-specific doses. We included 28 eligible studies with 3434 second cancer patients across 11 second solid cancers. Overall, there was little evidence that the dose-response curve was nonlinear in the direction of a downturn in risk, even at organ doses of ?60 Gy. Thyroid cancer was the only exception, with evidence of a downturn after 20 Gy. Generally the excess relative risk per Gray, taking account of age and sex, was 5 to 10 times lower than the risk from acute exposures of <2 Gy among the Japanese atomic bomb survivors. However, the magnitude of the reduction in risk varied according to the second cancer. The results of our review provide insights into radiation carcinogenesis from fractionated high-dose exposures and are generally consistent with current theoretical models. The results can be used to refine the development of second solid cancer risk projection models for novel radiation therapy techniques.

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

    SciTech Connect (OSTI)

    Bedford, Joel

    2014-04-18T23:59:59.000Z

    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.

  5. Polylogarithmic representation of radiative and thermodynamic properties of thermal radiation in a given spectral range: II. Real-body radiation

    E-Print Network [OSTI]

    Fisenko, Anatoliy I

    2015-01-01T23:59:59.000Z

    The general analytical expressions for the thermal radiative and thermodynamic properties of a real-body are obtained in a finite range of frequencies at different temperatures. The frequency dependence of the spectral emissivity is represented as a power series. The Stefan-Boltzmann law, total energy density, number density of photons, Helmholtz free energy density, internal energy density, enthalpy density, entropy density, heat capacity at constant volume, pressure, and total emissivity are expressed in terms of the polylogarithm functions. The general expressions for the thermal radiative and thermodynamic functions are applied for the study of thermal radiation of liquid and solid zirconium carbide. These functions are calculated using experimental data for the frequency dependence of the normal spectral emissivity in the visible-near infrared range at the melting (freezing) point. The gaps between the thermal radiative and thermodynamic functions of liquid and solid zirconium carbide are observed. The g...

  6. MOLECULAR MECHANISM OF SUPPRESSION OF NEOPLASTIC TRANSFORMATION BY LOW DOSES OF LOW LET RADIATION

    SciTech Connect (OSTI)

    J.LESIE REDPATH, PH.D.

    2011-03-29T23:59:59.000Z

    We are currently funded (9/01-8/04) by the DOE Low Dose Radiation Research Program to examine mechanisms underlying the suppression of neoplastic transformation in vitro by low doses of low LET radiation. For the new studies proposed under Notice 04-21, we intend to follow up on our observation that upregulation of DNA repair may be an important factor and that its importance is dose-dependent. The experimental system will be the human hybrid cell neoplastic transformation assay that we are currently using. We propose to test the following hypothesis: Down-regulation of DNA dsb repair will abrogate the low dose suppression of neoplastic transformation. Using the technique of RNA silencing, it is proposed to test the effect of down-regulation of the two major DNA dsb repair pathways, homologous recombination (HR) and non-homologous end-joining (NHEJ), on the dose response relationship for neoplastic transformation. Based on prior studies, we predict that this will result in abrogation of the suppressive effect at doses in the range 1 to 10 cGy, but not at lower doses. The proposed experiments will also help address the question as to which of the two DNA repair pathways may be the most important in causing suppression of transformation. HR is a pathway that is predominant in S and G2 phase cells and is known to be less error-prone than the NHEJ pathway that is predominant in G1 phase. We hypothesize that down-regulation of HR will result in the most effective abrogation of suppression. An important component of this study will be the determination of the how abrogation of DNA dsb repair impacts the spontaneous transformation frequency, presumably a consequence of endogeneous DNA damage. Experiments will be carried out using partially synchronized populations of cells enriched for G1 and S/G2 respectively. In addition to the endpoint of neoplastic transformation the impact of down-regulation of HR and NHEJ on the formation and disappearance of the DNA dsb marker, gamma-H2AX, will be studied.

  7. Cancer risks attributable to low doses of ionizing radiation: Assessing what we really know

    E-Print Network [OSTI]

    Brenner, David Jonathan

    Triangle Park, NC 27711; jOffice of Radiation and Indoor Air, Environmental Protection Agency, WashingtonCancer risks attributable to low doses of ionizing radiation: Assessing what we really know David J Infirmary, Oxford OX2 6ME, United Kingdom; dRadiation and Genome Stability Unit, Medical Research Council

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

    E-Print Network [OSTI]

    Yu, K.N.

    2006-01-01T23:59:59.000Z

    , radiation-sensi- tive, polymer between two protective layers of polyester, which allows the filmApplied Radiation and Isotopes 64 (2006) 60­62 Weak energy dependence of EBT gafchromic film dose are common in radiation therapy. r 2005 Elsevier Ltd. All rights reserved. Keywords: Radiochromic film

  9. Radiation Therapy With Full-Dose Gemcitabine and Oxaliplatin for Unresectable Pancreatic Cancer

    SciTech Connect (OSTI)

    Hunter, Klaudia U.; Feng, Felix Y. [Department of Radiation Oncology, University of Michigan, Ann Arbor, MI (United States); Griffith, Kent A. [Comprehensive Cancer Center Biostatistics Unit, University of Michigan, Ann Arbor, MI (United States); Francis, Isaac R. [Department of Radiology, University of Michigan, Ann Arbor, MI (United States); Lawrence, Theodore S. [Department of Radiation Oncology, University of Michigan, Ann Arbor, MI (United States); Desai, Sameer [Department of Internal Medicine, University of Michigan, Ann Arbor, MI (United States); Murphy, James D. [School of Medicine, University of Michigan, Ann Arbor, MI (United States); Zalupski, Mark M. [Department of Internal Medicine, University of Michigan, Ann Arbor, MI (United States); Ben-Josef, Edgar, E-mail: edgarb@med.umich.edu [Department of Radiation Oncology, University of Michigan, Ann Arbor, MI (United States)

    2012-07-01T23:59:59.000Z

    Purpose: We completed a Phase I trial of gemcitabine and oxaliplatin with concurrent radiotherapy in patients with previously untreated pancreatic cancer. The results of a subset of patients with unresectable disease who went on to receive planned additional therapy are reported here. Methods and Materials: All patients received two 28-day cycles of gemcitabine (1,000 mg/m{sup 2} on Days 1, 8, and 15) and oxaliplatin (40-85 mg/m{sup 2} on Days 1 and 15, per a dose-escalation schema). Radiation therapy was delivered concurrently with Cycle 1 (27 Gy in 1.8-Gy fractions). At 9 weeks, patients were reassessed for resectability. Those deemed to have unresectable disease were offered a second round of treatment consisting of 2 cycles of gemcitabine and oxaliplatin and 27 Gy of radiation therapy (total, 54 Gy). Radiation was delivered to the gross tumor volume plus 1 cm by use of a three-dimensional conformal technique. We used the Common Terminology Criteria for Adverse Events to assess acute toxicity. Late toxicity was scored per the Radiation Therapy Oncology Group scale. Computed tomography scans were reviewed to determine pattern of failure, local response, and disease progression. Kaplan-Meier methodology and Cox regression models were used to evaluate survival and freedom from failure. Results: Thirty-two patients from the Phase I dose-escalation study had unresectable disease, three of whom had low-volume metastatic disease. Of this group, 16 patients went on to receive additional therapy to complete a total of 4 cycles of chemotherapy and 54 Gy of concurrent radiation. For this subset, 38% had at least a partial tumor response at a median of 3.2 months. Median survival was 11.8 months (range, 4.4-26.3 months). The 1-year freedom from local progression rate was 93.8% (95% confidence interval, 63.2-99.1). Conclusions: Radiation therapy to 54 Gy with concurrent full-dose gemcitabine and oxaliplatin is well tolerated and results in favorable rates of local tumor response and 1-year freedom from local progression.

  10. Range and modulation dependencies for proton beam dose per monitor unit calculations

    SciTech Connect (OSTI)

    Hsi, Wen C.; Schreuder, Andries N.; Moyers, Michael F.; Allgower, Chris E.; Farr, Jonathan B.; Mascia, Anthony E. [Midwest Proton Radiotherapy Institute, Bloomington, Indiana 47408 and University Florida Proton Therapy Institute, Jacksonville, Florida 32206 (United States); ProCure Treatment Centers, Inc., Bloomington, Indiana 47404 (United States); Proton Therapy, Inc., Colton, California 92324 (United States); Midwest Proton Radiotherapy Institute, Bloomington, Indiana 47408 (United States); Midwest Proton Radiotherapy Institute, Bloomington, Indiana 47408 and Westdeutsches Protonentherapiezentrum, Universitaetsklinikum, Hufelandstrasse 55, 45147 Essen (Germany); Midwest Proton Radiotherapy Institute, Bloomington, Indiana 47408 (United States)

    2009-02-15T23:59:59.000Z

    Calculations of dose per monitor unit (D/MU) are required in addition to measurements to increase patient safety in the clinical practice of proton radiotherapy. As in conventional photon and electron therapy, the D/MU depends on several factors. This study focused on obtaining range and modulation dependence factors used in D/MU calculations for the double scattered proton beam line at the Midwest Proton Radiotherapy Institute. Three dependencies on range and one dependency on modulation were found. A carefully selected set of measurements was performed to discern these individual dependencies. Dependencies on range were due to: (1) the stopping power of the protons passing through the monitor chamber; (2) the reduction of proton fluence due to nuclear interactions within the patient; and (3) the variation of proton fluence passing through the monitor chamber due to different source-to-axis distances (SADs) for different beam ranges. Different SADs are produced by reconfigurations of beamline elements to provide different field sizes and ranges. The SAD effect on the D/MU varies smoothly as the beam range is varied, except at the beam range for which the first scatterers are exchanged and relocated to accommodate low and high beam ranges. A geometry factor was devised to model the SAD variation effect on the D/MU. The measured D/MU variation as a function of range can be predicted within 1% using the three modeled dependencies on range. Investigation of modulated beams showed that an analytical formula can predict the D/MU dependency as a function of modulation to within 1.5%. Special attention must be applied when measuring the D/MU dependence on modulation to avoid interplay between range and SAD effects.

  11. Integral radiation dose to normal structures with conformal external beam radiation

    SciTech Connect (OSTI)

    Aoyama, Hidefumi [Department of Human Oncology, University of Wisconsin, Madison, WI (United States) and Department of Radiology, Hokkaido University Graduate School of Medicine, Sapporo (Japan)]. E-mail: hao@radi.med.hokudai.ac.jp; Westerly, David Clark [Department of Medical Physics, University of Wisconsin, Madison, WI (United States); Mackie, Thomas Rockwell [Department of Human Oncology, University of Wisconsin, Madison, WI (United States); Department of Medical Physics, University of Wisconsin, Madison, WI (United States); TomoTherapy Inc., Madison, WI (United States); Olivera, Gustavo H. [Department of Medical Physics, University of Wisconsin, Madison, WI (United States); TomoTherapy Inc., Madison, WI (United States); Bentzen, Soren M. [Department of Human Oncology, University of Wisconsin, Madison, WI (United States); Department of Medical Physics, University of Wisconsin, Madison, WI (United States); Patel, Rakesh R. [Department of Human Oncology, University of Wisconsin, Madison, WI (United States); Jaradat, Hazim [Department of Human Oncology, University of Wisconsin, Madison, WI (United States); Tome, Wolfgang A. [Department of Human Oncology, University of Wisconsin, Madison, WI (United States); Department of Medical Physics, University of Wisconsin, Madison, WI (United States); Ritter, Mark A. [Department of Human Oncology, University of Wisconsin, Madison, WI (United States); Mehta, Minesh P. [Department of Human Oncology, University of Wisconsin, Madison, WI (United States)

    2006-03-01T23:59:59.000Z

    Background: This study was designed to evaluate the integral dose (ID) received by normal tissue from intensity-modulated radiotherapy (IMRT) for prostate cancer. Methods and Materials: Twenty-five radiation treatment plans including IMRT using a conventional linac with both 6 MV (6MV-IMRT) and 20 MV (20MV-IMRT), as well as three-dimensional conformal radiotherapy (3DCRT) using 6 MV (6MV-3DCRT) and 20 MV (20MV-3DCRT) and IMRT using tomotherapy (6MV) (Tomo-IMRT), were created for 5 patients with localized prostate cancer. The ID (mean dose x tissue volume) received by normal tissue (NTID) was calculated from dose-volume histograms. Results: The 6MV-IMRT resulted in 5.0% lower NTID than 6MV-3DCRT; 20 MV beam plans resulted in 7.7%-11.2% lower NTID than 6MV-3DCRT. Tomo-IMRT NTID was comparable to 6MV-IMRT. Compared with 6MV-3DCRT, 6MV-IMRT reduced IDs to the rectal wall and penile bulb by 6.1% and 2.7%, respectively. Tomo-IMRT further reduced these IDs by 11.9% and 16.5%, respectively. The 20 MV did not reduce IDs to those structures. Conclusions: The difference in NTID between 3DCRT and IMRT is small. The 20 MV plans somewhat reduced NTID compared with 6 MV plans. The advantage of tomotherapy over conventional IMRT and 3DCRT for localized prostate cancer was demonstrated in regard to dose sparing of rectal wall and penile bulb while slightly decreasing NTID as compared with 6MV-3DCRT.

  12. Total dose radiation response of plasma-damaged NMOS devices

    SciTech Connect (OSTI)

    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

    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.

  13. Electronic dose conversion technique using a NaI(Tl) detector for assessment of exposure dose rate from environmental radiation

    SciTech Connect (OSTI)

    Cho, G.; Kim, H.K. [Korea Advanced Inst. of Science and Technology, Taejon (Korea, Republic of)] [Korea Advanced Inst. of Science and Technology, Taejon (Korea, Republic of); Woo, H.; Oh, G. [Korea Electric Power Research Inst., Taejon (Korea, Republic of)] [Korea Electric Power Research Inst., Taejon (Korea, Republic of); Ha, D.K. [Samchang Enterprise Co., Anyang (Korea, Republic of)] [Samchang Enterprise Co., Anyang (Korea, Republic of)

    1998-06-01T23:59:59.000Z

    An electronic dose conversion technique to assess the exposure dose rate due to environmental radiation especially from terrestrial sources was developed. For a 2 x 2 inch cylindrical NaI(Tl) scintillation detector, pulse-height spectra were obtained for gamma-rays of energy up to 3 MeV by Monte Carlo simulation. Based on the simulation results and the experimentally fitted energy resolution, dose conversion factors were calculated by a numerical decomposition method. These calculated dose conversion factors were, then, electronically implemented to a developed dose conversion unit (DCU) which is a microprocessor-controlled single channel analyzer (SCA) with variable discrimination levels. The simulated spectra were confirmed by measurement of several monoenergetic gamma spectra with a multichannel analyzer (MCA). The converted exposure dose rates from the implemented dose conversion algorithm in the DCU were also evaluated for a field test in the vicinity of the nuclear power plant at Kori as well as for several standard sources, and the results were in good agreement with separate measurement by a high pressure ionization chamber (HPIC) within a 6.4% deviation.

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

    E-Print Network [OSTI]

    Zhang, Di

    2012-01-01T23:59:59.000Z

    helical multislice computed tomography examination. MedicalRadiation Dose in X-Ray Computed Tomography. AAPM report NO.of X-ray equipment for computed tomography. (2002). American

  15. assessing radiation dose: Topics by E-print Network

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

    doses and cancer rates to the workers m the first Soviet atom-bomb facility, near 2 Chelyabinsk and 4,600 at the plutonium sep- aration plant. If we allow for an average work...

  16. accumulated radiation dose: Topics by E-print Network

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

    doses and cancer rates to the workers m the first Soviet atom-bomb facility, near 2 Chelyabinsk and 4,600 at the plutonium sep- aration plant. If we allow for an average work...

  17. annual radiation dose: Topics by E-print Network

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

    doses and cancer rates to the workers m the first Soviet atom-bomb facility, near 2 Chelyabinsk and 4,600 at the plutonium sep- aration plant. If we allow for an average work...

  18. Radiation-induced chromosomal aberrations at different dose-rates

    E-Print Network [OSTI]

    McDaniel, Jackson Dean

    1965-01-01T23:59:59.000Z

    and sincere gratitude to Dr. G. M. Krise, for his advice and generosity, and to Dr. S. 0. Brown, for his vigilance throughout the course of this investigaticn. To Dr. H. R. Crookshank, I would like to acknowledge my indebtedness for serving as a sember... testicular cells eight hours postirradiation in animals given a total-body dose of 300 r at various dose rates . ; . . . . . . . . . . . , . . . . . . . . . . 17 II. Percentage of cells with aberrations per total dividing cells in the rat testes eight...

  19. Comparison of Kodak EDR2 and Gafchromic EBT film for intensity-modulated radiation therapy dose distribution verification

    SciTech Connect (OSTI)

    Sankar, A. [Department of Radiation Oncology, Apollo Specialty Hospital, Chennai (India) and Department of Physics, Anna University, Chennai (India)]. E-mail: asankar_phy@yahoo.co.in; Ayyangar, Komanduri M. [Department of Radiation Oncology, University of Nebraska Medical Center, Omaha, NE (United States); Nehru, R. Mothilal [Department of Radiation Oncology, University of Nebraska Medical Center, Omaha, NE (United States); Gopalakrishna Kurup, P.G. [Department of Radiation Oncology, Apollo Specialty Hospital, Chennai (India); Murali, V. [Department of Radiation Oncology, Apollo Specialty Hospital, Chennai (India); Enke, Charles A. [Department of Radiation Oncology, University of Nebraska Medical Center, Omaha, NE (United States); Velmurugan, J. [Department of Physics, Anna University, Chennai (India)

    2006-01-01T23:59:59.000Z

    The quantitative dose validation of intensity-modulated radiation therapy (IMRT) plans require 2-dimensional (2D) high-resolution dosimetry systems with uniform response over its sensitive region. The present work deals with clinical use of commercially available self-developing Radio Chromic Film, Gafchromic EBT film, for IMRT dose verification. Dose response curves were generated for the films using a VXR-16 film scanner. The results obtained with EBT films were compared with the results of Kodak extended dose range 2 (EDR2) films. The EBT film had a linear response between the dose range of 0 to 600 cGy. The dose-related characteristics of the EBT film, such as post irradiation color growth with time, film uniformity, and effect of scanning orientation, were studied. There was up to 8.6% increase in the color density between 2 to 40 hours after irradiation. There was a considerable variation, up to 8.5%, in the film uniformity over its sensitive region. The quantitative differences between calculated and measured dose distributions were analyzed using DTA and Gamma index with the tolerance of 3% dose difference and 3-mm distance agreement. The EDR2 films showed consistent results with the calculated dose distributions, whereas the results obtained using EBT were inconsistent. The variation in the film uniformity limits the use of EBT film for conventional large-field IMRT verification. For IMRT of smaller field sizes (4.5 x 4.5 cm), the results obtained with EBT were comparable with results of EDR2 films.

  20. Page 1 of 3 RADIATION DOSE IS MORE THAN A NUMBER!

    E-Print Network [OSTI]

    Perkins, Richard A.

    , Former Director of Radiological Physics Center, MD Anderson Cancer Center #12;Page 2 of 3 RADIATION DOSE of Radiation Larry Dewerd, University of Wisconsin Will Hanson, Former Director of Radiological Physics Center for solicited research Service ­ NIH-based facility (RPC-like) or fee for service or private non-profit (AAALAC

  1. Analysis of radiation doses from operation of postulated commercial spent fuel transportation systems: Main report

    SciTech Connect (OSTI)

    Schneider, K.J.; Hostick, C.J.; Ross, W.A.; Peterson, R.W.; Smith, R.I.; Stiles, D.L.; Daling, P.M.; Weakley, S.A.; Grinde, R.B.; Young, J.R.

    1987-11-01T23:59:59.000Z

    This report contains a system study of estimated radiation doses to the public and workers resulting from the transport of spent fuel from commercial nuclear power reactors to a geologic repository. The report contains a detailed breakdown of activities and a description of time/distance/dose-rate estimates for each activity within the system. Collective doses are estimated for each of the major activities at the reactor site, in transit, and at the repository receiving facility. Annual individual doses to the maximally exposed individuals or groups of individuals are also estimated. A total of 17 alternatives and subalternatives to the postulated reference transportation system are identified, conceptualized, and their dose-reduction potentials and costs estimated. Resulting ratios of ..delta..cost/..delta..collective system dose for each alternative relative to the postulated reference transportation system are given. Most of the alternatives evaluated are estimated to provide both cost and dose reductions. Major reductions in transportation system dose and cost are estimated to result from using higher-capacity rail and truck casks, and particularly when replacing legalweight truck casks with ''advanced design'' overweight truck casks. The greatest annual dose reduction to the highest exposed individual workers (i.e., at the repository) is estimated to be achieved by using remote handling equipment for the cask handling operations at the repository. Additional shielding is also effective in reducing doses to both radiation workers at the reactor and repository and to transport workers. 69 refs., 36 figs., 156 tabs.

  2. Radiation Dose-Volume Effects and the Penile Bulb

    SciTech Connect (OSTI)

    Roach, Mack, E-mail: mroach@radonc.ucsf.ed [Department of Radiation Oncology, University of California-San Francisco, San Francisco, CA (United States); Nam, Jiho [Department of Radiation Oncology, University of North Carolina at Chapel Hill, Chapel Hill, NC (United States); Gagliardi, Giovanna [Department of Medical Physics, Karolinska University Hospital and Karolinska Institutet, Stockholm (Sweden); El Naqa, Issam; Deasy, Joseph O. [Department of Radiation Oncology, School of Medicine, Washington University in St. Louis, St. Louis, MO (United States); Marks, Lawrence B. [Department of Radiation Oncology, University of North Carolina at Chapel Hill, Chapel Hill, NC (United States)

    2010-03-01T23:59:59.000Z

    The dose, volume, and clinical outcome data for penile bulb are reviewed for patients treated with external-beam radiotherapy. Most, but not all, studies find an association between impotence and dosimetric parameters (e.g., threshold doses) and clinical factors (e.g., age, comorbid diseases). According to the data available, it is prudent to keep the mean dose to 95% of the penile bulb volume to <50 Gy. It may also be prudent to limit the D70 and D90 to 70 Gy and 50 Gy, respectively, but coverage of the planning target volume should not be compromised. It is acknowledged that the penile bulb may not be the critical component of the erectile apparatus, but it seems to be a surrogate for yet to be determined structure(s) critical for erectile function for at least some techniques.

  3. Spatially resolved measurement of high doses in microbeam radiation therapy using samarium doped fluorophosphate glasses

    SciTech Connect (OSTI)

    Okada, Go; Morrell, Brian; Koughia, Cyril; Kasap, Safa [Department of Electrical and Computer Engineering, University of Saskatchewan, Saskatoon, SK S7N 5A9 (Canada); Edgar, Andy; Varoy, Chris [School of Chemical and Physical Sciences and MacDiarmid Institute, Victoria University of Wellington, Kelburn Parade (New Zealand); Belev, George; Wysokinski, Tomasz [Canadian Light Source Inc., University of Saskatchewan, Saskatoon, SK S7N 0X4 (Canada); Chapman, Dean [Department of Anatomy and Cell Biology, University of Saskatchewan, Saskatoon, SK S7N 5E5 (Canada)

    2011-09-19T23:59:59.000Z

    The measurement of spatially resolved high doses in microbeam radiation therapy has always been a challenging task, where a combination of high dose response and high spatial resolution (microns) is required for synchrotron radiation peaked around 50 keV. The x-ray induced Sm{sup 3+}{yields} Sm{sup 2+} valence conversion in Sm{sup 3+} doped fluorophosphates glasses has been tested for use in x-ray dosimetry for microbeam radiation therapy. The conversion efficiency depends almost linearly on the dose of irradiation up to {approx}5 Gy and saturates at doses exceeding {approx}80 Gy. The conversion shows strong correlation with x-ray induced absorbance of the glass which is related to the formation of phosphorus-oxygen hole centers. When irradiated through a microslit collimator, a good spatial resolution and high ''peak-to-valley'' contrast have been observed by means of confocal photoluminescence microscopy.

  4. Standard Guide for Absorbed-Dose Mapping in Radiation Processing Facilities

    E-Print Network [OSTI]

    American Society for Testing and Materials. Philadelphia

    2003-01-01T23:59:59.000Z

    1.1 This document provides guidance in determining absorbed-dose distributions in products, materials or substances irradiated in gamma, X-ray (bremsstrahlung) and electron beam facilities. Note 1—For irradiation of food and the radiation sterilization of health care products, other specific ISO and ISO/ASTM standards containing dose mapping requirements exist. For food irradiation, see ISO/ASTM 51204, Practice for Dosimetry in Gamma Irradiation Facilities for Food Processing and ISO/ASTM 51431, Practice for Dosimetry in Electron and Bremsstrahlung Irradiation Facilities for Food Processing. For the radiation sterilization of health care products, see ISO 11137: 1995, Sterilization of Health Care Products Requirements for Validation and Routine Control Radiation Sterilization. In those areas covered by ISO 11137, that standard takes precedence. ISO/ASTM Practice 51608, ISO/ASTM Practice 51649, and ISO/ASTM Practice 51702 also contain dose mapping requirements. 1.2 Methods of analyzing the dose map data ar...

  5. Radiation and litigation : analyses of the ALARA principle and low dose radiation in the courts, and the future of radiation in court cases

    E-Print Network [OSTI]

    Esparza, Enrique

    2006-01-01T23:59:59.000Z

    Currently there are a growing number of radiation workers. In order to ensure the safety of the employees, regulations have been established by the federal government and state governments to limit the dose equivalent to ...

  6. 75Radiation Dose and Distance This iconic photo was

    E-Print Network [OSTI]

    on March 15, a few days after the Japan 2011 earthquake, which caused severe damage to the Fukushima Press/Kyodo News) The devastating Japan 2011 earthquake damaged the nuclear reactors in Fukushima, which: Date Distance (km) Location Dose Rate (microSeiverts/hr) March 15 1 km Fukushima #2 plant 8,200 March

  7. Observation of a Dose-Control Relationship for Lung and Liver Tumors After Stereotactic Body Radiation Therapy

    SciTech Connect (OSTI)

    McCammon, Robert [Department of Radiation Oncology, University of Colorado Health Sciences Center, Aurora, CO (United States)], E-mail: Robert.mccammon@uchsc.edu; Schefter, Tracey E.; Gaspar, Laurie E.; Zaemisch, Rebekah; Gravdahl, Daniel; Kavanagh, Brian [Department of Radiation Oncology, University of Colorado Health Sciences Center, Aurora, CO (United States)

    2009-01-01T23:59:59.000Z

    Purpose: To determine prognostic factors for local control of primary or metastatic tumors within the lung or liver treated with stereotactic body radiation therapy (SBRT) within a single institution. Methods and Materials: The records of 141 consecutive patients with 246 lesions treated with three-fraction SBRT from Oct 1999 through Aug 2005 were reviewed. Local control was assessed radiographically. Univariate and multivariate analyses were performed to evaluate the influence of the following factors on local control: total dose, expressed as either nominal prescription dose or equivalent uniform dose (EUD); gross tumor volume; primary site; treatment site (lung vs. other); histologic characteristics (adenocarcinoma vs. other); gender; age; and primary vs. metastatic tumor. Results: On univariate analysis, increased dose (either nominal or EUD) and smaller gross tumor volume were significant predictors of higher local control. Lesions treated to a nominal dose of 54 Gy or greater had a 3-year actuarial local control rate of 89.3% compared with 59.0% and 8.1% for those treated to 36-53.9 Gy and less than 36 Gy. On multivariate analysis, only increased nominal dose and EUD retained statistical significance. Treatment was well tolerated; 5.7% of patients experienced Grade 3 or higher toxicity. Conclusions: This large single-institution series suggests a dose-control relationship within the range of SBRT doses applied. Excellent local control rates are achieved with a nominal dose of 54 Gy or greater, corresponding to an EUD greater than 65.3 Gy. These results support the use of aggressive SBRT regimens when durable tumor control is the primary objective.

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

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

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

    2015-04-30T23:59:59.000Z

    Despite their potential vulnerability to contaminants from exposure at multiple life stages, amphibians are one of the least studied groups of vertebrates in ecotoxicology, and research on radiation effects in amphibians is scarce. We used multiple endpoints to assess the radiosensitivity of the southern toad (Anaxyrus [Bufo] terrestris) during its pre-terrestrial stages of development –embryonic, larval, and metamorphic. Toads were exposed, from several hours after oviposition through metamorphosis (up to 77 days later), to four low dose rates of ¹³?Cs at 0.13, 2.4, 21, and 222 mGy d?¹, resulting in total doses up to 15.8 Gy. Radiation treatments did notmore »affect hatching success of embryos, larval survival, or the length of the larval period. The individual family variation in hatching success of embryos was larger than the radiation response. In contrast, newly metamorphosed individuals from the higher dose-rate treatments had higher mass and mass/length body indices, a measure which may relate to higher post-metamorphic survival. The increased mass and index at higher dose rates may indicate that the chronic, low dose rate radiation exposures triggered secondary responses. Additionally, the increases in growth were linked to a decrease in DNA damage (as measured by the Comet Assay) in red blood cells at a dose rate of 21mGy d?¹ and a total dose of 1.1 Gy. In conclusion, the complex effects of low dose rates of ionizing radiation may trigger growth and cellular repair mechanisms in amphibian larvae.« less

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

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

    Stark, Karolina [Stockholm Univ. (Sweden); Univ. of Georgia, Aiken, SC (United States); Scott, David E. [Univ. of Georgia, Aiken, SC (United States); Tsyusko, Olga [Univ. of Georgia, Aiken, SC (United States); Univ. of Kentucky, Lexington, KY (United States); Coughlin, Daniel P. [Univ. of Georgia, Aiken, SC (United States); Hinton, Thomas G. [Univ. of Georgia, Aiken, SC (United States); Inst. of Radiation Protection and Nuclear Safety, Cadarache (France); Amendola, Roberto [ENEA, (Italy)

    2015-04-30T23:59:59.000Z

    Despite their potential vulnerability to contaminants from exposure at multiple life stages, amphibians are one of the least studied groups of vertebrates in ecotoxicology, and research on radiation effects in amphibians is scarce. We used multiple endpoints to assess the radiosensitivity of the southern toad (Anaxyrus [Bufo] terrestris) during its pre-terrestrial stages of development –embryonic, larval, and metamorphic. Toads were exposed, from several hours after oviposition through metamorphosis (up to 77 days later), to four low dose rates of ¹³?Cs at 0.13, 2.4, 21, and 222 mGy d?¹, resulting in total doses up to 15.8 Gy. Radiation treatments did not affect hatching success of embryos, larval survival, or the length of the larval period. The individual family variation in hatching success of embryos was larger than the radiation response. In contrast, newly metamorphosed individuals from the higher dose-rate treatments had higher mass and mass/length body indices, a measure which may relate to higher post-metamorphic survival. The increased mass and index at higher dose rates may indicate that the chronic, low dose rate radiation exposures triggered secondary responses. Additionally, the increases in growth were linked to a decrease in DNA damage (as measured by the Comet Assay) in red blood cells at a dose rate of 21mGy d?¹ and a total dose of 1.1 Gy. In conclusion, the complex effects of low dose rates of ionizing radiation may trigger growth and cellular repair mechanisms in amphibian larvae.

  10. Method for detecting radiation dose utilizing thermoluminescent material

    DOE Patents [OSTI]

    Miller, S.D.; McDonald, J.C.; Eichner, F.N.; Durham, J.S.

    1992-08-04T23:59:59.000Z

    The amount of ionizing radiation to which a thermoluminescent material has been exposed is determined by first cooling the thermoluminescent material and then optically stimulating the thermoluminescent material by exposure to light. Visible light emitted by the thermoluminescent material as it is allowed to warm up to room temperature is detected and counted. The thermoluminescent material may be annealed by exposure to ultraviolet light. 5 figs.

  11. Static jaw collimation settings to minimize radiation dose to normal brain tissue during stereotactic radiosurgery

    SciTech Connect (OSTI)

    Han, Eun Young, E-mail: eyhan@uams.edu [Department of Radiation Oncology, University of Arkansas for Medical Sciences, Little Rock, AR (United States); Zhang Xin; Yan Yulong; Sharma, Sunil; Penagaricano, Jose [Department of Radiation Oncology, University of Arkansas for Medical Sciences, Little Rock, AR (United States); Moros, Eduardo [Department of Radiation Oncology, Moffitt Cancer Center, Tampa, FL (United States); Corry, Peter [Department of Radiation Oncology, University of Arkansas for Medical Sciences, Little Rock, AR (United States)

    2012-01-01T23:59:59.000Z

    At University of Arkansas for Medical Sciences (UAMS) intracranial stereotactic radiosurgery (SRS) is performed by using a linear accelerator with an add-on micromultileaf collimator (mMLC). In our clinical setting, static jaws are automatically adapted to the furthest edge of the mMLC-defined segments with 2-mm (X jaw) and 5-mm (Y jaw) margin and the same jaw values are applied for all beam angles in the treatment planning system. This additional field gap between the static jaws and the mMLC allows additional radiation dose to normal brain tissue. Because a radiosurgery procedure consists of a single high dose to the planning target volume (PTV), reduction of unnecessary dose to normal brain tissue near the PTV is important, particularly for pediatric patients whose brains are still developing or when a critical organ, such as the optic chiasm, is near the PTV. The purpose of this study was to minimize dose to normal brain tissue by allowing minimal static jaw margin around the mMLC-defined fields and different static jaw values for each beam angle or arc. Dose output factors were measured with various static jaw margins and the results were compared with calculated doses in the treatment planning system. Ten patient plans were randomly selected and recalculated with zero static jaw margins without changing other parameters. Changes of PTV coverage, mean dose to predefined normal brain tissue volume adjacent to PTV, and monitor units were compared. It was found that the dose output percentage difference varied from 4.9-1.3% for the maximum static jaw opening vs. static jaw with zero margins. The mean dose to normal brain tissue at risk adjacent to the PTV was reduced by an average of 1.9%, with negligible PTV coverage loss. This dose reduction strategy may be meaningful in terms of late effects of radiation, particularly in pediatric patients. This study generated clinical knowledge and tools to consistently minimize dose to normal brain tissue.

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

    SciTech Connect (OSTI)

    Azzam, Edouard I

    2013-01-16T23:59:59.000Z

    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.

  13. On the use of age-specific effective dose coefficients in radiation protection of the public

    SciTech Connect (OSTI)

    Kocher, D.C.; Eckerman, K.F.

    1998-11-01T23:59:59.000Z

    Current radiation protection standards for the public include a limit on effective dose in any year for individuals in critical groups. This paper considers the question of how the annual dose limit should be applied in controlling routine exposures of populations consisting of individuals of all ages. The authors assume that the fundamental objective of radiation protection is limitation of lifetime risk and, therefore, that standards for controlling routine exposures of the public should provide a reasonable correspondence with lifetime risk, taking into account the age dependence of intakes and doses and the variety of radionuclides and exposure pathways of concern. Using new calculations of the per capita (population-averaged) risk of cancer mortality per unit activity inhaled or ingested in the US Environmental Protection Agency`s Federal Guidance Report No. 13, the authors show that applying a limit on annual effective dose only to adults, which was the usual practice in radiation protection of the public before the development of age-specific effective dose coefficients, provides a considerably better correspondence with lifetime risk than applying the annual dose limit to the critical group of any age.

  14. Radiation dose estimates for typical piloted NTR lunar and Mars mission engine operations

    SciTech Connect (OSTI)

    Schnitzler, B.G. (EG and G Idaho, Inc., Idaho Falls, ID (United States)); Borowski, S.K. (National Aeronautics and Space Administration, Cleveland, OH (United States). Lewis Research Center)

    1991-01-01T23:59:59.000Z

    The natural and manmade radiation environments to be encountered during lunar and Mars missions are qualitatively summarized. The computational methods available to characterize the radiation environment produced by an operating nuclear propulsion system are discussed. Mission profiles and vehicle configurations are presented for a typical all-propulsive, fully reusable lunar mission and for a typical all-propulsive Mars mission. Estimates of crew location biological doses are developed for all propulsive maneuvers. Post-shutdown dose rates near the nuclear engine are estimated at selected mission times. 15 refs., 4 figs.

  15. RADIATION DOSE ESTIMATES TO ADULTS AND CHILDREN FROM VARIOUS

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What's Possible forPortsmouth/Paducah47,193.70COMMUNITYResponses: QuestionDaniel Hartsock CIMMS,RADIATION

  16. Radiation Dose to the Lens During Craniospinal Irradiation-An Improvement in Proton Radiotherapy Technique

    SciTech Connect (OSTI)

    Cochran, David M. [Division of Health Sciences and Technology, Harvard Medical School and Massachusetts Institute of Technology, Cambridge, MA (United States); Yock, Torunn I.; Adams, Judith A. C. [Department of Radiation Oncology, Massachusetts General Hospital, Harvard Medical School, Boston, MA (United States); Tarbell, Nancy J. [Department of Radiation Oncology, Massachusetts General Hospital, Harvard Medical School, Boston, MA (United States)], E-mail: ntarbell@partners.org

    2008-04-01T23:59:59.000Z

    Purpose: To evaluate the effect of angle modification of cranial field proton beam therapy on the radiation dose delivered to the lens during craniospinal irradiation (CSI). Methods and Materials: Thirty-nine patients with central nervous system tumors who received CSI with a posterior fossa boost were analyzed for the radiation dose to the lens. Thirteen patients received cranial field treatment using standard opposed-lateral proton beams, and 26 patients received treatment with angled posterior-oblique proton beams. The lens dose in a test case also was evaluated by comparing conventional X-rays with the two proton beam planning methods by using a CMS/Xio three-dimensional planning system. Results: Substantial lens dose sparing was realized with the angling of the cranial proton beams 15{sup o}-20{sup o} to the posterior. In the 39 treated patients who were analyzed (median age, 7 years), average dose delivered to the lens was decreased by approximately 50% by angling of the proton beams, with the average maximum dose decreasing from 74% to 40% of the prescribed dose (p < 0.0001). Significant lens sparing was seen in patients 10 years and younger (median age, 6 years; p < 0.0001), whereas an insignificant decrease was seen in older patients (median age, 16 years; p = 0.14). With the opposed-lateral technique (median age, 6 years), the lens dose increased significantly with decreasing age (p = 0.002), whereas there was no effect of age on lens dose in the angled beam-treated group (median age, 8.5 years; p = 0.73). Conclusion: The present study clearly shows an advantage in sparing of the lens dose by angling the beams used during proton beam CSI. This effect is most pronounced in patients 10 years and younger because of anatomic effects of sinus development.

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

    SciTech Connect (OSTI)

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

    2013-05-14T23:59:59.000Z

    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.

  18. Subsequent Malignancies in Children Treated for Hodgkin's Disease: Associations With Gender and Radiation Dose

    SciTech Connect (OSTI)

    Constine, Louis S. [Department of Radiation Oncology, James P. Wilmot Cancer Center at University of Rochester, Rochester, NY (United States); Department of Pediatrics, James P. Wilmot Cancer Center at University of Rochester, Rochester, NY (United States)], E-mail: louis_constine@urmc.rochester.edu; Tarbell, Nancy [Department of Pediatric Radiation Oncology, Massachusetts General Hospital, Boston, MA (United States); Hudson, Melissa M. [Department of Hematology-Oncology, St. Jude Children's Research Hospital, Memphis, TN (United States); Schwartz, Cindy [Department of Hematology-Oncology, Johns Hopkins Hospital, Baltimore, MD (United States); Fisher, Susan G. [Department of Community and Preventative Medicine, James P. Wilmot Cancer Center at University of Rochester, Rochester, NY (United States); Muhs, Ann G. B.A. [Department of Radiation Oncology, James P. Wilmot Cancer Center at University of Rochester, Rochester, NY (United States); Basu, Swati K. [Department of Community and Preventative Medicine, James P. Wilmot Cancer Center at University of Rochester, Rochester, NY (United States); Kun, Larry E. [Department of Radiological Sciences, St. Jude Children's Research Hospital, Memphis, TN (United States); Ng, Andrea; Mauch, Peter [Department of Radiation Oncology, Brigham and Women's Hospital, Boston, MA (United States); Sandhu, Ajay [Department of Radiation Oncology, University of California Medical Center-San Diego, San Diego, CA (United States); Culakova, Eva [Department of Community and Preventative Medicine, James P. Wilmot Cancer Center at University of Rochester, Rochester, NY (United States); Lyman, Gary [Department of Medicine, Duke University Medical Center, Durham, NC (United States); Mendenhall, Nancy [Department of Radiation Oncology, University of Florida Medical Center, Gainesville, FL (United States)

    2008-09-01T23:59:59.000Z

    Purpose: Subsequent malignant neoplasms (SMNs) are a dominant cause of morbidity and mortality in children treated for Hodgkin's disease (HD). We evaluated select demographic and therapeutic factors associated with SMNs, specifically gender and radiation dose. Methods and Materials: A total of 930 children treated for HD at five institutions between 1960 and 1990 were studied. Mean age at diagnosis was 13.6 years, and mean follow-up was 16.8 years (maximum, 39.4 years). Treatment included radiation alone (43%), chemotherapy alone (9%), or both (48%). Results: We found that SMNs occurred in 102 (11%) patients, with a 25-year actuarial rate of 19%. With 15,154 patient years of follow-up, only 7.18 cancers were expected (standardized incidence ratio [SIR] = 14.2; absolute excess risk [AER] = 63 cases/10,000 years). The SIR for female subjects, 19.93, was significantly greater than for males, 8.41 (p < 0.0001). After excluding breast cancer, the SIR for female patients was 15.4, still significantly greater than for male patients (p = 0.0012). Increasing radiation dose was associated with an increasing SIR (p = 0.0085). On univariate analysis, an increased risk was associated with female gender, increasing radiation dose, and age at treatment (12-16 years). Using logistic regression, mantle radiation dose increased risk, and this was 2.5-fold for female patients treated with more than 35 Gy primarily because of breast cancer. Conclusions: Survivors of childhood HD are at risk for SMNs, and this risk is greater for female individuals even after accounting for breast cancer. Although SMNs occur in the absence of radiation therapy, the risk increases with RT dose.

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

    SciTech Connect (OSTI)

    Daila S. Gridley, PhD

    2012-03-30T23:59:59.000Z

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

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

    SciTech Connect (OSTI)

    Speiser, B.L. (St. Joseph's Hospital and Medical Center, Phoenix, AZ (United States)); Spratling, L.

    1993-03-15T23:59:59.000Z

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

  1. Modeling proton intensity gradients and radiation dose equivalents in the inner

    E-Print Network [OSTI]

    Pringle, James "Jamie"

    Modeling proton intensity gradients and radiation dose equivalents in the inner heliosphere using exposure in IP space. In this paper, we utilize EMMREM to study the radial dependence of proton peak crossfield diffusion at large radial distances. Our results show that radial dependencies of proton peak

  2. Page 1 of 3 RADIATION DOSE IS MORE THAN A NUMBER!

    E-Print Network [OSTI]

    Magee, Joseph W.

    Page 1 of 3 RADIATION DOSE IS MORE THAN A NUMBER! Agenda National Institute of Standards Metting, DOE Janice Huff, NASA 12:00 PM Important Concepts in Radiobiology Dosimetry David Followill, MD.m. Dosimetry Larry Dewerd, University of Wisconsin Current Calibration and Standardization Methods 4:15 p

  3. Parotid Glands Dose–Effect Relationships Based on Their Actually Delivered Doses: Implications for Adaptive Replanning in Radiation Therapy of Head-and-Neck Cancer

    SciTech Connect (OSTI)

    Hunter, Klaudia U. [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States); Fernandes, Laura L. [Department of Biostatistics, University of Michigan, Ann Arbor, Michigan (United States); Vineberg, Karen A.; McShan, Daniel; Antonuk, Alan E. [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States); Cornwall, Craig [Department of Hospital Dentistry, University of Michigan, Ann Arbor, Michigan (United States); Feng, Mary [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States); Schipper, Mathew J. [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States); Department of Biostatistics, University of Michigan, Ann Arbor, Michigan (United States); Balter, James M. [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States); Eisbruch, Avraham, E-mail: eisbruch@umich.edu [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States)

    2013-11-15T23:59:59.000Z

    Purpose: Doses actually delivered to the parotid glands during radiation therapy often exceed planned doses. We hypothesized that the delivered doses correlate better with parotid salivary output than the planned doses, used in all previous studies, and that determining these correlations will help make decisions regarding adaptive radiation therapy (ART) aimed at reducing the delivered doses. Methods and Materials: In this prospective study, oropharyngeal cancer patients treated definitively with chemoirradiation underwent daily cone-beam computed tomography (CBCT) with clinical setup alignment based on the C2 posterior edge. Parotid glands in the CBCTs were aligned by deformable registration to calculate cumulative delivered doses. Stimulated salivary flow rates were measured separately from each parotid gland pretherapy and periodically posttherapy. Results: Thirty-six parotid glands of 18 patients were analyzed. Average mean planned doses was 32 Gy, and differences from planned to delivered mean gland doses were ?4.9 to +8.4 Gy, median difference +2.2 Gy in glands in which delivered doses increased relative to planned. Both planned and delivered mean doses were significantly correlated with posttreatment salivary outputs at almost all posttherapy time points, without statistically significant differences in the correlations. Large dispersions (on average, SD 3.6 Gy) characterized the dose–effect relationships for both. The differences between the cumulative delivered doses and planned doses were evident at first fraction (r=.92, P<.0001) because of complex setup deviations (eg, rotations and neck articulations), uncorrected by the translational clinical alignments. Conclusions: After daily translational setup corrections, differences between planned and delivered doses in most glands were small relative to the SDs of the dose–saliva data, suggesting that ART is not likely to gain measurable salivary output improvement in most cases. These differences were observed at first treatment, indicating potential benefit for more complex setup corrections or adaptive interventions in the minority of patients with large deviations detected early by CBCT.

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

    SciTech Connect (OSTI)

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

    1995-05-01T23:59:59.000Z

    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.

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

    SciTech Connect (OSTI)

    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

    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.

  6. Radiation dose delivered to the proximal penis as a predictor of the risk of erectile dysfunction after three-dimensional conformal radiotherapy for localized prostate cancer

    SciTech Connect (OSTI)

    Wernicke, A. Gabriella [Department of Radiation Oncology, Jefferson Medical College and Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, Pennsylvania (United States); Valicenti, Richard [Department of Radiation Oncology, Jefferson Medical College and Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, Pennsylvania (United States)]. E-mail: richard.valicenti@mail.tju.edu; DiEva, Kelly [Department of Radiation Oncology, Jefferson Medical College and Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, Pennsylvania (United States); Houser, Christopher [Department of Radiation Oncology, Jefferson Medical College and Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, Pennsylvania (United States); Pequignot, Ed [Department of Medicine, Jefferson Medical College and Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA (United States)

    2004-12-01T23:59:59.000Z

    Purpose/objective: In this study, we evaluated in a serial manner whether radiation dose to the bulb of the penis is predictive of erectile dysfunction, ejaculatory difficulty (EJ), and overall satisfaction with sex life (quality of life) by using serial validated self-administered questionnaires. Methods and materials: Twenty-nine potent men with AJCC Stage II prostate cancer treated with three-dimensional conformal radiation therapy alone to a median dose 72.0 Gy (range: 66.6-79.2 Gy) were evaluated by determining the doses received by the penile bulb. The penile bulb was delineated volumetrically, and the dose-volume histogram was obtained on each patient. Results: The median follow-up time was 35 months (range, 16-43 months). We found that for D{sub 30}, D{sub 45}, D{sub 60}, and D{sub 75} (doses to a percent volume of PB: 30%, 45%, 60%, and 75%), higher than the corresponding median dose (defined as high-dose group) correlated with an increased risk of impotence (erectile dysfunction firmness score = 0) (odds ratio [OR] = 7.5, p = 0.02; OR = 7.5, p = 0.02; OR = 8.6, p = 0.008; and OR = 6.9, p = 0.015, respectively). Similarly, for EJD D{sub 30}, D{sub 45}, D{sub 60}, and D{sub 75}, doses higher than the corresponding median ones correlated with worsening ejaculatory function score (EJ = 0 or 1) (OR = 8, p = 0.013; OR = 8, p 0.013; OR = 9.2, p = 0.015; and OR = 8, p = 0.026, respectively). For quality of life, low ({<=}median dose) dose groups of patients improve over time, whereas high-dose groups of patients worsen. Conclusions: This study supports the existence of a penile bulb dose-volume relationship underlying the development of radiation-induced erectile dysfunction. Our data may guide the use of inverse treatment planning to maximize the probability of maintaining sexual potency after radiation therapy.

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

    SciTech Connect (OSTI)

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

    2012-11-01T23:59:59.000Z

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

  8. ASSESSMENT OF UNCERTAINTY IN THE RADIATION DOSES FOR THE TECHA RIVER DOSIMETRY SYSTEM

    SciTech Connect (OSTI)

    Napier, Bruce A.; Degteva, M. O.; Anspaugh, L. R.; Shagina, N. B.

    2009-10-23T23:59:59.000Z

    In order to provide more accurate and precise estimates of individual dose (and thus more precise estimates of radiation risk) for the members of the ETRC, a new dosimetric calculation system, the Techa River Dosimetry System-2009 (TRDS-2009) has been prepared. The deterministic version of the improved dosimetry system TRDS-2009D was basically completed in April 2009. Recent developments in evaluation of dose-response models in light of uncertain dose have highlighted the importance of different types of uncertainties in the development of individual dose estimates. These include uncertain parameters that may be either shared or unshared within the dosimetric cohort, and also the nature of the type of uncertainty as aleatory or epistemic and either classical or Berkson. This report identifies the nature of the various input parameters and calculational methods incorporated in the Techa River Dosimetry System (based on the TRDS-2009D implementation), with the intention of preparing a stochastic version to estimate the uncertainties in the dose estimates. This report reviews the equations, databases, and input parameters, and then identifies the author’s interpretations of their general nature. It presents the approach selected so that the stochastic, Monte-Carlo, implementation of the dosimetry System - TRDS-2009MC - will provide useful information regarding the uncertainties of the doses.

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

    E-Print Network [OSTI]

    Patel, Jyoti Shivabhai

    1988-01-01T23:59:59.000Z

    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...

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

    DOE Data Explorer [Office of Scientific and Technical Information (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.

  11. Effective gamma-ray doses due to natural radiation from soils of southeastern Brazil

    SciTech Connect (OSTI)

    Silveira, M. A. G.; Moreira, R. H.; Bellini, B. S. [Centro Universitario da FEI, Sao Bernardo do Campo, Sao Paulo (Brazil); Medina, N. H.; Aguiar, V. A. P. [Instituto de Fisica da Universidade de Sao Paulo, Sao Paulo (Brazil)

    2010-08-04T23:59:59.000Z

    We have used gamma-ray spectrometry to study the distribution of natural radiation from soils of southeastern Brazil: Billings reservoir, Sao Bernardo do Campo Parks, Diadema Parks, Interlagos region, Sao Paulo, and soil from Sao Paulo and Rio de Janeiro beaches. In most of the regions studied we have found that the dose due the external exposure to gamma-rays, proceeding from natural terrestrial elements, are between the values 0.3 and 0.6 mSv/year, established by the United Nations Scientific Committee on the Effects of Atomic Radiation.

  12. Radiation dose reduction in medical CT through equally sloped tomography Benjamin P. Fahimian1,2,6

    E-Print Network [OSTI]

    Soatto, Stefano

    Council on Radiation Protection & Measurements10 , CT accounts for about 15% of the total radiological50Radiation dose reduction in medical CT through equally sloped tomography Benjamin P. Fahimian1 Department of Radiation Oncology, Stanford University, Stanford, CA 94305 3 Biomedical Physics

  13. Short CommunicationJ. Radiat. Res., 53, 475481 (2012) Triphasic Low-dose Response in Zebrafish Embryos Irradiated by

    E-Print Network [OSTI]

    Yu, K.N.

    2012-01-01T23:59:59.000Z

    the linear no-threshold (LNT) hypothesis for radiation protection considerations, which assumes that the riskShort CommunicationJ. Radiat. Res., 53, 475­481 (2012) Triphasic Low-dose Response in Zebrafish, the experimental data were in line with induc- tion of radiation-induced bystander effect as well as rescue effect

  14. High-dose MVCT image guidance for stereotactic body radiation therapy

    SciTech Connect (OSTI)

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

    2012-08-15T23:59:59.000Z

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

  15. Radiation Dose-Volume Effects in the Stomach and Small Bowel

    SciTech Connect (OSTI)

    Kavanagh, Brian D., E-mail: Brian.Kavanagh@ucdenver.ed [Department of Radiation Oncology, University of Colorado-Denver School of Medicine, Aurora, CO (United States); Pan, Charlie C. [Department of Radiation Oncology, University of Michigan Medical School, Ann Arbor, MI (United States); Dawson, Laura A. [Department of Radiation Oncology, Princess Margaret Hospital, University of Toronto, Toronto, ON (Canada); Das, Shiva K. [Department of Radiation Oncology, Duke University Medical Center, Durham, NC (United States); Li, X. Allen [Department of Radiation Oncology, Medical College of Wisconsin, Milwaukee, WI (United States); Ten Haken, Randall K.; Miften, Moyed [Department of Radiation Oncology, University of Colorado-Denver School of Medicine, Aurora, CO (United States)

    2010-03-01T23:59:59.000Z

    Published data suggest that the risk of moderately severe (>=Grade 3) radiation-induced acute small-bowel toxicity can be predicted with a threshold model whereby for a given dose level, D, if the volume receiving that dose or greater (VD) exceeds a threshold quantity, the risk of toxicity escalates. Estimates of VD depend on the means of structure segmenting (e.g., V15 = 120 cc if individual bowel loops are outlined or V45 = 195 cc if entire peritoneal potential space of bowel is outlined). A similar predictive model of acute toxicity is not available for stomach. Late small-bowel/stomach toxicity is likely related to maximum dose and/or volume threshold parameters qualitatively similar to those related to acute toxicity risk. Concurrent chemotherapy has been associated with a higher risk of acute toxicity, and a history of abdominal surgery has been associated with a higher risk of late toxicity.

  16. Automated systems for measuring dose and radiation quality as a function of time

    SciTech Connect (OSTI)

    Braby, L.A.; Conroy, T.J.; Elegy, D.C.; Brackenbush, L.W. [Pacific Northwest Lab., Richland, WA (United States); Badhwar, G.D. [Johnson Space Center, Houston, TX (United States)

    1992-09-01T23:59:59.000Z

    A compact, modular, tissue equivalent proportional counter system has been developed for use in space. The data acquisition system consists of a microcomputer, multi channel analyzer, memory, and power converter on individual circuit cards which can be used in various combinations for specific measurement requirements. The system uses separate, interchangeable detectors, each with its preamplifier and shaping amplifier connected directly to the detector. The microprocessor provides the computing power of a personal computer, and utilizes an operating system which is compatible with a subset of MSDOS. Experiment procedures can be programmed in high level languages and down loaded to the microprocessor. A typical application, used to characterize the dose rates due to trapped radiations in space, monitors the dose rate and records energy deposition spectra frequently when the dose rate is high. The microprocessor also measures and records system operation characteristics such as MCA linearity, proportional counter gain, and power supply voltages on a periodic basis.

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

    E-Print Network [OSTI]

    Bateman, Sarah Caroline Louisa

    1986-01-01T23:59:59.000Z

    calculational dose response. 25 9 Counts per minute of "'I as obtained using a 1" x 1" Nal external probe bioassay system as a function of '"I activity present. 26 INTRODUCTION The objective of this research is to measure the radiation absorbed dose from... dosimeter system, the energy imparted by radiation causes the ferrous ions present in the solution to be converted to ferric ions, so that the number of iona converted is proportional to the radiation absorbed dose (Gu78a). However in the FBX dosimeter...

  18. Technology Assessment and Roadmap for the Emergency Radiation Dose Assessment Program

    SciTech Connect (OSTI)

    Turteltaub, K W; Hartman-Siantar, C; Easterly, C; Blakely, W

    2005-10-03T23:59:59.000Z

    A Joint Interagency Working Group (JIWG) under the auspices of the Department of Homeland Security Office of Research and Development conducted a technology assessment of emergency radiological dose assessment capabilities as part of the overall need for rapid emergency medical response in the event of a radiological terrorist event in the United States. The goal of the evaluation is to identify gaps and recommend general research and development needs to better prepare the Country for mitigating the effects of such an event. Given the capabilities and roles for responding to a radiological event extend across many agencies, a consensus of gaps and suggested development plans was a major goal of this evaluation and road-mapping effort. The working group consisted of experts representing the Departments of Homeland Security, Health and Human Services (Centers for Disease Control and the National Institutes of Health), Food and Drug Administration, Department of Defense and the Department of Energy's National Laboratories (see appendix A for participants). The specific goals of this Technology Assessment and Roadmap were to: (1) Describe the general context for deployment of emergency radiation dose assessment tools following terrorist use of a radiological or nuclear device; (2) Assess current and emerging dose assessment technologies; and (3) Put forward a consensus high-level technology roadmap for interagency research and development in this area. This report provides a summary of the consensus of needs, gaps and recommendations for a research program in the area of radiation dosimetry for early response, followed by a summary of the technologies available and on the near-term horizon. We then present a roadmap for a research program to bring present and emerging near-term technologies to bear on the gaps in radiation dose assessment and triage. Finally we present detailed supporting discussion on the nature of the threats we considered, the status of technology today, promising emerging technologies and references for further reading.

  19. Medical imaging using ionizing radiation: Optimization of dose and image quality in fluoroscopy

    SciTech Connect (OSTI)

    Jones, A. Kyle, E-mail: kyle.jones@mdanderson.org [Department of Imaging Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030 (United States); Balter, Stephen [Departments of Radiology and Medicine, Columbia University, New York, New York 10032 (United States)] [Departments of Radiology and Medicine, Columbia University, New York, New York 10032 (United States); Rauch, Phillip [Retired-Henry Ford Health System, Detroit, Michigan 48202 (United States)] [Retired-Henry Ford Health System, Detroit, Michigan 48202 (United States); Wagner, Louis K. [Department of Diagnostic and Interventional Imaging, The University of Texas Medical School at Houston, Houston, Texas 77030 (United States)] [Department of Diagnostic and Interventional Imaging, The University of Texas Medical School at Houston, Houston, Texas 77030 (United States)

    2014-01-15T23:59:59.000Z

    The 2012 Summer School of the American Association of Physicists in Medicine (AAPM) focused on optimization of the use of ionizing radiation in medical imaging. Day 2 of the Summer School was devoted to fluoroscopy and interventional radiology and featured seven lectures. These lectures have been distilled into a single review paper covering equipment specification and siting, equipment acceptance testing and quality control, fluoroscope configuration, radiation effects, dose estimation and measurement, and principles of flat panel computed tomography. This review focuses on modern fluoroscopic equipment and is comprised in large part of information not found in textbooks on the subject. While this review does discuss technical aspects of modern fluoroscopic equipment, it focuses mainly on the clinical use and support of such equipment, from initial installation through estimation of patient dose and management of radiation effects. This review will be of interest to those learning about fluoroscopy, to those wishing to update their knowledge of modern fluoroscopic equipment, to those wishing to deepen their knowledge of particular topics, such as flat panel computed tomography, and to those who support fluoroscopic equipment in the clinic.

  20. 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

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

    1999-04-29T23:59:59.000Z

    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.

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

    SciTech Connect (OSTI)

    Messaris, Gerasimos A. T.; Abatzis, Ilias; Kagadis, George C.; Samartzis, Alexandros P.; Athanasopoulou, Panagiota; Christeas, Nikolaos; Katsanos, Konstantinos; Karnabatidis, Dimitrios; Nikiforidis, George C. [Department of Medical Physics, University Hospital of Patras, GR 265 04 Rion (Greece); Department of Medical Physics, School of Medicine, University of Patras, GR 265 04 Rion (Greece); Department of Medical Physics, University Hospital of Patras, GR 265 04 Rion, Greece and Department of Medical Physics, School of Medicine, University of Patras, GR 265 04 Rion (Greece); Department of Medical Physics, 'EVANGELISMOS' General Hospital, 45-47 Ypsilantou Street, GR 106 76 Athens (Greece); Philips Hellas, 44 Kifisias Avenue, GR 151 25 Marousi (Greece); Department of Radiology, School of Medicine, University of Patras, GR 265 04 Rion (Greece); Department of Medical Physics, University Hospital of Patras, GR 265 04 Rion, Greece and Department of Medical Physics, School of Medicine, University of Patras, GR 265 04 Rion (Greece)

    2012-07-15T23:59:59.000Z

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

  2. The Radiation Dose Measurement System for the BaBar Electromagnetic Calorimeter

    SciTech Connect (OSTI)

    Khan, A.; /Brunel U.; Meyer, W.T.; /Iowa State U.; Stelzer, J.; /Stanford U., Phys. Dept.; Yi, Jong; /Manchester U.

    2006-08-14T23:59:59.000Z

    An array of 116 p-channel radiation sensitive MOSFET transistors (RadFETs) has been operational for the past 6 years at the BaBar experiment at the PEP-II asymmetric B-Factory at the Stanford Linear Accelerator Center (SLAC). This system maps the integrated dose absorbed by different regions of the Electromagnetic Calorimeter (EMC) during the running of the experiment. We report on the design and implementation of the system and finally, the performance of the monitoring system during the last 6 years of BaBar data-taking.

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

    SciTech Connect (OSTI)

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

    2013-05-15T23:59:59.000Z

    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 Â?Â?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.

  4. MicroShield analysis to calculate external radiation dose rates for several spent fuel casks

    SciTech Connect (OSTI)

    Marincel, M.K. [Missouri Univ., Rolla, MO (United States); Weiner, R.F.; Osborn, D.M. [Sandia National Laboratories, Albuquerque, NM (United States)

    2007-07-01T23:59:59.000Z

    The purpose of this MicroShield analysis is to calculate the external radiation, primarily gamma, dose rate for spent fuel casks. The reason for making this calculation is that currently all analyses of transportation risk assume that this external dose rate is the maximum allowed by regulation, 10 mrem/hr at 2 m from the casks, and the risks of incident-free transportation are thus always overestimated to an unknown extent. In order to do this, the program by Grove Software, MicroShield 7.01, was used to model three Nuclear Regulatory Commission (NRC) approved casks: HI-STAR 100, GA-4, and NAC-STC, loaded with specific source material. Dimensions were obtained from NUREG/CR-6672 and the Certificates of Compliance for each respective cask. Detectors were placed at the axial point at 1 m and 2 m from the outer gamma shielding of the casks. In the April 8, 2004 publication of the Federal Register, a notice of intent to prepare a Supplemental Yucca Mountain Environmental Impact Statement (DOE/EIS-0250F-S1) was published by the Office of Civilian Radioactive Waste Management (OCRWM) in order to consider design, construction, operation, and transportation of spent nuclear fuel to the Yucca Mountain repository [1]. These more accurate estimates of the external dose rates could be used in order to provide a more risk-informed analysis. (authors)

  5. Radiation and Reason Why radiation at modest dose rates is quite harmless and current radiation safety regulations are flawed

    E-Print Network [OSTI]

    CERN. Geneva

    2013-01-01T23:59:59.000Z

    Data on the impact of ionising radiation on life are examined in the light of evolutionary biology. This comparison confirms that fear of nuclear radiation is not justified by science itself; rather it originates in a failure of public trust in nuclear science, a relic of the international politics of the Cold War era. Current ionisation safety regulations appease this fear but without scientific support and they need fundamental reformulation. This should change the reaction to accidents like Fukushima, the cost of nuclear energy and the application of nuclear technology to the supply of food and fresh water. Such a boost to the world economy would require that more citizens study and appreciate the science involved – and then tell others -- not as much fun as the Higgs, perhaps, but no less important! www.radiationandreason.com

  6. Simultaneous reduction of radiation dose and scatter for CBCT by using collimators

    SciTech Connect (OSTI)

    Li, Tianfang; Li, Xiang; Yang, Yong; Zhang, Yongqian; Heron, Dwight E.; Huq, M. Saiful [Department of Radiation Oncology, University of Pittsburgh Cancer Institute, Pittsburgh, Pennsylvania 15232 (United States)] [Department of Radiation Oncology, University of Pittsburgh Cancer Institute, Pittsburgh, Pennsylvania 15232 (United States)

    2013-12-15T23:59:59.000Z

    Purpose: On-board cone-beam CT (CBCT) imaging has been widely available in radiotherapy clinic for target localization. However, the extra radiation dose from CBCT is always a concern for its frequent use. Additionally, the relatively large scatter in CBCT often degrades the image quality. By using collimators, some of the X-rays can be stopped from reaching the patient and the detectors, hence both the scatter and the patient doses are simultaneously reduced. The authors show in this work that the collimated CBCT data can be reconstructed without any noticeable artifacts for certain collimator blocking ratios and blocking patterns, and the focus of this work is to study the relationship between the image quality and these two collimator factors.Methods: A CBCT system with collimators was simulated following the typical geometry used in clinic. Different collimator designs were tested by varying the size and the number of the collimator slits, and at the same time, the ratio of transmitted beams to total beams was varied from 100% to 10%, resulting in hundreds of different simulation scenarios. Lung and pelvis phantoms created from patients CT images were used in the simulations, and an iterative reconstruction algorithm using the compressed sensing technique was adopted. The image quality was examined by root mean square errors (RMSEs) and compared with the conventional CBCT images.Results: The CBCT image quality increases as the amount of beams passing through the collimators increases, and decreases as the size of the collimator slits increases. With ultra-high resolution collimators, the RMSEs were comparable to the conventional CBCT image quality until the beam transmission rate is reduced below 25%.Conclusions: Collimators can reduce the scatters and radiation dose, however, the collimated CBCT image quality is strongly dependent on both the collimator blocking ratio and the blocking pattern. To achieve image quality comparable to the conventional CBCT, the amount of information and data format must be adequate.

  7. The prediction of radiation-induced liver dysfunction using a local dose and regional venous perfusion model

    SciTech Connect (OSTI)

    Cao Yue; Platt, Joel F.; Francis, Isaac R; Balter, James M.; Pan, Charlie; Normolle, Daniel; Ben-Josef, Edgar; Haken, Randall K. ten; Lawrence, Theodore S. [Departments of Radiation Oncology and Radiology, University of Michigan, Ann Arbor, Michigan 48109-0010 (United States); Department of Radiology, University of Michigan, Ann Arbor, Michigan 48109-0010 (United States); Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan 48109-0010 (United States)

    2007-02-15T23:59:59.000Z

    We have shown that high dose conformal radiation combined with chemotherapy appears to prolong the survival of patients with unresectable intrahepatic cancers. The ability to safely deliver higher doses is primarily limited by the development of radiation-induced liver disease, characterized by venous occlusion. In this study, we investigated whether portal venous perfusion measured prior to the end of radiation therapy (RT) together with dose could predict liver venous perfusion dysfunction after treatment. Ten patients with unresectable intrahepatic cancer participated in an IRB-approved computer tomography (CT) perfusion study. Hepatic arterial and portal vein perfusion distributions were estimated by using dynamic contrast enhanced CT and the single compartmental model. Scans were obtained at four time points: prior to treatment, after 15 and 30 fractions of 1.5 Gy treatments, and one month following the completion of RT. Multivariant linear regression was used to determine covariances among the first three time point measurements plus dose for prediction of the post RT measurement. The reduction in the regional venous perfusion one month following RT was predicted by the local accumulated dose and the change in the regional venous perfusion after {approx}30 fractions (F=90.6,p<0.000 01). Each Gy produced an approximately 1.2% of reduction in the venous perfusion. This local dose and venous perfusion model has the potential to predict individual sensitivity to radiation. This is the first step toward developing a method to deliver higher and potentially more curative radiation doses to the patients who can safely receive these higher doses.

  8. Long-Term Outcomes After High-Dose Postprostatectomy Salvage Radiation Treatment

    SciTech Connect (OSTI)

    Goenka, Anuj; Magsanoc, Juan Martin; Pei Xin; Schechter, Michael; Kollmeier, Marisa; Cox, Brett [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, NY (United States)] [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, NY (United States); Scardino, Peter T.; Eastham, James A. [Urology Service, Department of Surgery, Memorial Sloan-Kettering Cancer Center, New York, NY (United States)] [Urology Service, Department of Surgery, Memorial Sloan-Kettering Cancer Center, New York, NY (United States); Zelefsky, Michael J., E-mail: zelefskm@mskcc.org [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, NY (United States)

    2012-09-01T23:59:59.000Z

    Purpose: To review the impact of high-dose radiotherapy (RT) in the postprostatectomy salvage setting on long-term biochemical control and distant metastases-free survival, and to identify clinical and pathologic predictors of outcomes. Methods and Materials: During 1988-2007, 285 consecutive patients were treated with salvage RT (SRT) after radical prostatectomy. All patients were treated with either three-dimensional conformal RT or intensity-modulated RT. Two hundred seventy patients (95%) were treated to a dose {>=}66 Gy, of whom 205 (72%) received doses {>=}70 Gy. Eighty-seven patients (31%) received androgen-deprivation therapy as a component of their salvage treatment. All clinical and pathologic records were reviewed to identify treatment risk factors and response. Results: The median follow-up time after SRT was 60 months. Seven-year actuarial prostate-specific antigen (PSA) relapse-free survival and distant metastases-free survival were 37% and 77%, respectively. Independent predictors of biochemical recurrence were vascular invasion (p < 0.01), negative surgical margins (p < 0.01), presalvage PSA level >0.4 ng/mL (p < 0.01), androgen-deprivation therapy (p = 0.03), Gleason score {>=}7 (p = 0.02), and seminal vesicle involvement (p = 0.05). Salvage RT dose {>=}70 Gy was not associated with improvement in biochemical control. A doubling time <3 months was the only independent predictor of metastatic disease (p < 0.01). There was a trend suggesting benefit of SRT dose {>=}70 Gy in preventing clinical local failure in patients with radiographically visible local disease at time of SRT (7 years: 90% vs. 79.1%, p = 0.07). Conclusion: Salvage RT provides effective long-term biochemical control and freedom from metastasis in selected patients presenting with detectable PSA after prostatectomy. Androgen-deprivation therapy was associated with improvement in biochemical progression-free survival. Clinical local failures were rare but occurred most commonly in patients with greater burden of disease at time of SRT as reflected by either radiographic imaging or a greater PSA level. Salvage radiation doses {>=}70 Gy may ultimately be most beneficial in these patients, but this needs to be further studied.

  9. CY 1995 radiation dose reconciliation report and resulting CY 1996 dose estimate for the 324 nuclear facility

    SciTech Connect (OSTI)

    Landsman, S.D.; Thornhill, R.E.; Peterson, C.A.

    1996-04-01T23:59:59.000Z

    In this report, the dose estimate for CY 1995 is reconciled by month wih actual doses received. Results of the reconciliation were used to revise estimates of worker dose for CY 1996. Resulting dose estimate for the facility is also included. Support for two major programs (B-Cell Cleanout and Surveillance and Maintenance) accounts for most of the exposure received by workers in the faility. Most of the expousre received by workers comes from work in the Radiochemical Engineering Complex airlock. In spite of schedule and work scope changes during CY 1995, dose estimates were close to actual exposures received. A number of ALARA measures were taken throughout the year; exposure reduction due to those was 20.6 Man-Rem, a 28% reduction from the CY 1995 estimate. Baseline estimates for various tasks in the facility were used to compile the CY 1996 dose estimate of 45.4 Man-Rem; facility goal for CY 1996 is to reduce worker dose by 20%, to 36.3 Man-Rem.

  10. Primate polonium metabolic models and their use in estimation of systemic radiation doses from bioassay data. Final report

    SciTech Connect (OSTI)

    Cohen, N. [New York Univ. Medical Center, Tuxedo, NY (United States). Dept. of Environmental Medicine

    1989-03-15T23:59:59.000Z

    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.

  11. System and method for radiation dose calculation within sub-volumes of a monte carlo based particle transport grid

    DOE Patents [OSTI]

    Bergstrom, Paul M. (Livermore, CA); Daly, Thomas P. (Livermore, CA); Moses, Edward I. (Livermore, CA); Patterson, Jr., Ralph W. (Livermore, CA); Schach von Wittenau, Alexis E. (Livermore, CA); Garrett, Dewey N. (Livermore, CA); House, Ronald K. (Tracy, CA); Hartmann-Siantar, Christine L. (Livermore, CA); Cox, Lawrence J. (Los Alamos, NM); Fujino, Donald H. (San Leandro, CA)

    2000-01-01T23:59:59.000Z

    A system and method is disclosed for radiation dose calculation within sub-volumes of a particle transport grid. In a first step of the method voxel volumes enclosing a first portion of the target mass are received. A second step in the method defines dosel volumes which enclose a second portion of the target mass and overlap the first portion. A third step in the method calculates common volumes between the dosel volumes and the voxel volumes. A fourth step in the method identifies locations in the target mass of energy deposits. And, a fifth step in the method calculates radiation doses received by the target mass within the dosel volumes. A common volume calculation module inputs voxel volumes enclosing a first portion of the target mass, inputs voxel mass densities corresponding to a density of the target mass within each of the voxel volumes, defines dosel volumes which enclose a second portion of the target mass and overlap the first portion, and calculates common volumes between the dosel volumes and the voxel volumes. A dosel mass module, multiplies the common volumes by corresponding voxel mass densities to obtain incremental dosel masses, and adds the incremental dosel masses corresponding to the dosel volumes to obtain dosel masses. A radiation transport module identifies locations in the target mass of energy deposits. And, a dose calculation module, coupled to the common volume calculation module and the radiation transport module, for calculating radiation doses received by the target mass within the dosel volumes.

  12. A phase I/II trial of stereotactic body radiation therapy (SBRT) for lung metastases: Initial report of dose escalation and early toxicity

    SciTech Connect (OSTI)

    Schefter, Tracey E. [Department of Radiation Oncology, University of Colorado Health Sciences Center, Aurora, CO (United States)]. E-mail: Tracey.Schefter@uchsc.edu; Kavanagh, Brian D. [Department of Radiation Oncology, University of Colorado Health Sciences Center, Aurora, CO (United States); Raben, David [Department of Radiation Oncology, University of Colorado Health Sciences Center, Aurora, CO (United States); Kane, Madeleine [Division of Medical Oncology, University of Colorado Health Sciences Center, Aurora, CO (United States); Chen Changhu [Department of Radiation Oncology, University of Colorado Health Sciences Center, Aurora, CO (United States); Stuhr, Kelly [Department of Radiation Oncology, University of Colorado Health Sciences Center, Aurora, CO (United States); Kelly, Karen [Division of Medical Oncology, University of Colorado Health Sciences Center, Aurora, CO (United States); Mitchell, John D. [Section of Thoracic Surgery, University of Colorado Health Sciences Center, Aurora, CO (United States); Bunn, Paul A. [Division of Medical Oncology, University of Colorado Health Sciences Center, Aurora, CO (United States); Gaspar, Laurie E. [Department of Radiation Oncology, University of Colorado Health Sciences Center, Aurora, CO (United States)

    2006-11-15T23:59:59.000Z

    Purpose: To determine the maximum tolerated dose (MTD) of stereotactic body radiation therapy (SBRT) for lung metastases. Methods and Materials: A Phase I clinical trial was conducted. Eligible patients had one to three pulmonary metastases from a solid tumor, cumulative tumor diameter <7 cm, and adequate pulmonary function (forced expiratory volume in 1 s {>=}1.0 L). The planning target volume (PTV) was typically constructed from the gross tumor volume (GTV) by adding a 5-mm radial and 10-mm craniocaudal margin. The first cohort received 48 Gy to the PTV in three fractions (F). SBRT dose was escalated in subsequent cohorts up to a preselected maximum of 60 Gy/3 F. The percent of normal lung receiving more than 15 Gy (V{sub 15}) was restricted to less than 35%. Respiratory control and a dynamic conformal arc SBRT technique were used. Dose-limiting toxicity (DLT) included acute Grade 3 lung or esophageal toxicity or any acute Grade 4 toxicity within 3 months. After the Phase I dose escalation, the trial continued as a Phase II study, and patients in this cohort are included to increase the number of patients evaluable for early toxicity assessment. Results: Twenty-five eligible patients have been enrolled to date. In the Phase I component of the trial, there were 12 patients (7 male, 5 female): median age, 55 years (range, 31-83 years); the most common primary site was colorectal (4 patients). Seven patients had two lung lesions, and 1 patient had three lesions. The median aggregate volume of all GTVs was 18.7 mL (range, 2-40 mL). No patient experienced a DLT, and dose was escalated to 60 Gy/3 F without reaching the MTD; including the additional Phase II cohort patients, 16 patients have been treated to a dose of 60 Gy/3F without experiencing a DLT in the first 3 months. The equivalent uniform dose to the GTV in the highest dose group ranged from 66 to 77 Gy in 3 F. Conclusions: In patients with limited pulmonary metastases, radiobiologically potent doses of SBRT are well tolerated with minimal early toxicity. A Phase II SBRT study of 60 Gy/3 F for lung metastases is ongoing to evaluate local tumor control rates with this regimen and continue surveillance for any late effects.

  13. SU-E-I-15: Comparison of Radiation Dose for Radiography and EOS in Adolescent Scoliosis Patients

    SciTech Connect (OSTI)

    Schueler, B; Walz-Flannigan, A [Mayo Clinic, Rochester, MN (United States)

    2014-06-01T23:59:59.000Z

    Purpose: To estimate patient radiation dose for whole spine imaging using EOS, a new biplanar slot-scanning radiographic system and compare with standard scoliosis radiography. Methods: The EOS imaging system (EOS Imaging, Paris, France) consists of two orthogonal x-ray fan beams which simultaneously acquire frontal and lateral projection images of a standing patient. The patient entrance skin air kerma was measured for each projection image using manufacturer-recommended exposure parameters for spine imaging. Organ and effective doses were estimated using a commercially-available Monte Carlo simulation program (PCXMC, STUK, Radiation and Nuclear Safety Authority, Helsinki, Finland) for a 15 year old mathematical phantom model. These results were compared to organ and effective dose estimated for scoliosis radiography using computed radiography (CR) with standard exposure parameters obtained from a survey of pediatric radiographic projections. Results: The entrance skin air kerma for EOS was found to be 0.18 mGy and 0.33 mGy for posterior-anterior (PA) and lateral projections, respectively. This compares to 0.76 mGy and 1.4 mGy for CR, PA and lateral projections. Effective dose for EOS (PA and lateral projections combined) is 0.19 mSv compared to 0.51 mSv for CR. Conclusion: The EOS slot-scanning radiographic system allows for reduced patient radiation dose in scoliosis patients as compared to standard CR radiography.

  14. A Phase I Clinical and Pharmacology Study Using Amifostine as a Radioprotector in Dose-escalated Whole Liver Radiation Therapy

    SciTech Connect (OSTI)

    Feng, Mary, E-mail: maryfeng@umich.edu [Department of Radiation Oncology, School of Medicine, University of Michigan, Ann Arbor, Michigan (United States)] [Department of Radiation Oncology, School of Medicine, University of Michigan, Ann Arbor, Michigan (United States); Smith, David E. [Department of Pharmaceutical Sciences, College of Pharmacy, University of Michigan, Ann Arbor, Michigan (United States)] [Department of Pharmaceutical Sciences, College of Pharmacy, University of Michigan, Ann Arbor, Michigan (United States); Normolle, Daniel P. [Department of Biostatistics, University of Pittsburgh, Pittsburgh, Pennsylvania (United States)] [Department of Biostatistics, University of Pittsburgh, Pittsburgh, Pennsylvania (United States); Knol, James A. [Department of Surgery, School of Medicine, University of Michigan, Ann Arbor, Michigan (United States)] [Department of Surgery, School of Medicine, University of Michigan, Ann Arbor, Michigan (United States); Pan, Charlie C.; Ben-Josef, Edgar [Department of Radiation Oncology, School of Medicine, University of Michigan, Ann Arbor, Michigan (United States)] [Department of Radiation Oncology, School of Medicine, University of Michigan, Ann Arbor, Michigan (United States); Lu Zheng; Feng, Meihua R.; Chen Jun [Department of Pharmaceutical Sciences, College of Pharmacy, University of Michigan, Ann Arbor, Michigan (United States)] [Department of Pharmaceutical Sciences, College of Pharmacy, University of Michigan, Ann Arbor, Michigan (United States); Ensminger, William [Department of Internal Medicine, School of Medicine, University of Michigan, Ann Arbor, Michigan (United States)] [Department of Internal Medicine, School of Medicine, University of Michigan, Ann Arbor, Michigan (United States); Lawrence, Theodore S. [Department of Radiation Oncology, School of Medicine, University of Michigan, Ann Arbor, Michigan (United States)] [Department of Radiation Oncology, School of Medicine, University of Michigan, Ann Arbor, Michigan (United States)

    2012-08-01T23:59:59.000Z

    Purpose: Diffuse intrahepatic tumors are difficult to control. Whole-liver radiotherapy has been limited by toxicity, most notably radiation-induced liver disease. Amifostine is a prodrug free-radical scavenger that selectively protects normal tissues and, in a preclinical model of intrahepatic cancer, systemic amifostine reduced normal liver radiation damage without compromising tumor effect. We hypothesized that amifostine would permit escalation of whole-liver radiation dose to potentially control microscopic disease. We also aimed to characterize the pharmacokinetics of amifostine and its active metabolite WR-1065 to optimize timing of radiotherapy. Methods and Materials: We conducted a radiation dose-escalation trial for patients with diffuse, intrahepatic cancer treated with whole-liver radiation and intravenous amifostine. Radiation dose was assigned using the time-to-event continual reassessment method. A companion pharmacokinetic study was performed. Results: Twenty-three patients were treated, with a maximum dose of 40 Gy. Using a logistical regression model, compared with our previously treated patients, amifostine increased liver tolerance by 3.3 {+-} 1.1 Gy (p = 0.007) (approximately 10%) with similar response rates. Peak concentrations of WR-1065 were 25 {mu}M with an elimination half-life of 1.5 h; these levels are consistent with radioprotective effects of amifostine in patients. Conclusion: These findings demonstrate for the first time that amifostine is a normal liver radioprotector. They further suggest that it may be useful to combine amifostine with fractionated or stereotactic body radiation therapy for patients with focal intrahepatic cancer.

  15. Identification and Characterization of Soluble Factors Involved in Delayed Effects of Low Dose Radiation. Final report

    SciTech Connect (OSTI)

    Baulch, Janet

    2013-09-11T23:59:59.000Z

    This is a 'glue grant' that was part of a DOE Low Dose project entitled 'Identification and Characterization of Soluble Factors Involved in Delayed Effects of Low Dose Radiation'. This collaborative program has involved Drs. David L. Springer from Pacific Northwest National Laboratory (PNNL), John H. Miller from Washington State University, Tri-cities (WSU) and William F. Morgan then from the University of Maryland, Baltimore (UMB). In July 2008, Dr. Morgan moved to PNNL and Dr. Janet E. Baulch became PI for this project at University of Maryland. In November of 2008, a one year extension with no new funds was requested to complete the proteomic analyses. The project stemmed from studies in the Morgan laboratory demonstrating that genomically unstable cells secret a soluble factor or factors into the culture medium, that cause cytogenetic aberrations and apoptosis in normal parental GM10115 cells. The purpose of this project was to identify the death inducing effect (DIE) factor or factors, estimate their relative abundance, identify the cell signaling pathways involved and finally recapitulate DIE in normal cells by exogenous manipulation of putative DIE factors in culture medium. As reported in detail in the previous progress report, analysis of culture medium from the parental cell line, and stable and unstable clones demonstrated inconsistent proteomic profiles as relate to candidate DIE factors. While the proposed proteomic analyses did not provide information that would allow DIE factors to be identified, the analyses provided another important set of observations. Proteomic analysis suggested that proteins associated with the cellular response to oxidative stress and mitochondrial function were elevated in the medium from unstable clones in a manner consistent with mitochondrial dysfunction. These findings correlate with previous studies of these clones that demonstrated functional differences between the mitochondria of stable and unstable clones. These mitochondrial abnormalities in the unstable clones contributes to oxidative stress.

  16. Experimental and Simulation of Gamma Radiation Dose Rate for High Exposure Building Material

    E-Print Network [OSTI]

    Abbasi, Akbar

    2015-01-01T23:59:59.000Z

    Natural radioactivity concentrations in high exposure building materials are commonly used in Iran, which is measured a direct exposure by using {\\gamma}-ray spectrometry. The values for 226Ra, 232Th and 40K were in the ranges 3.8 - 94.2, 6.5 - 172.2 and 556.9 - 1539.2 Bqkg-1, respectively. The absorbed dose rates in the standard dwelling room due to 238U, 232Th series and 40K were calculated with MCNPX code. The simulation and experimental results were between 7.95 - 41.74 and 8.36 - 39.99 nGy h-1, respectively. These results were compared with experimental outing and there was overlap closely. The simulation results are able to develop for any kind of dwelling places.

  17. Experimental and Simulation of Gamma Radiation Dose Rate for High Exposure Building Material

    E-Print Network [OSTI]

    Akbar Abbasi; Mustfa Hassanzadeh

    2014-10-27T23:59:59.000Z

    Natural radioactivity concentrations in high exposure building materials are commonly used in Iran, which is measured a direct exposure by using {\\gamma}-ray spectrometry. The values for 226Ra, 232Th and 40K were in the ranges 3.8 - 94.2, 6.5 - 172.2 and 556.9 - 1539.2 Bqkg-1, respectively. The absorbed dose rates in the standard dwelling room due to 238U, 232Th series and 40K were calculated with MCNPX code. The simulation and experimental results were between 7.95 - 41.74 and 8.36 - 39.99 nGy h-1, respectively. These results were compared with experimental outing and there was overlap closely. The simulation results are able to develop for any kind of dwelling places.

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

    SciTech Connect (OSTI)

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

    2012-10-01T23:59:59.000Z

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

  19. Increased Radiation Dose to Overweight and Obese Patients from Radiographic Examinations

    E-Print Network [OSTI]

    Yanch, Jacquelyn C.

    Purpose: To estimate the increase in effective dose from diagnostic x-rays for overweight and obese adult patients compared with „lean? reference phantoms. Materials and Methods: Relative effective doses, E/E[subscript 0], ...

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

    SciTech Connect (OSTI)

    Yi Ying; Lai, Chao-Jen; Han Tao; Zhong Yuncheng; Shen Youtao; Liu Xinming; Ge Shuaiping; You Zhicheng; Wang Tianpeng; Shaw, Chris C. [Department of Imaging Physics, University of Texas MD Anderson Cancer Center, Houston, Texas 77030 (United States)

    2011-02-15T23:59:59.000Z

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

  1. Early Brain Response to Low-Dose Radiation Exposure Involves Molecular Networks and Pathways Associated with Cognitive Functions, Advanced Aging and Alzheimer's Disease

    SciTech Connect (OSTI)

    Lowe, Xiu R; Bhattacharya, Sanchita; Marchetti, Francesco; Wyrobek, Andrew J.

    2008-06-06T23:59:59.000Z

    Understanding the cognitive and behavioral consequences of brain exposures to low-dose ionizing radiation has broad relevance for health risks from medical radiation diagnostic procedures, radiotherapy, environmental nuclear contamination, as well as earth orbit and space missions. Analyses of transcriptome profiles of murine brain tissue after whole-body radiation showed that low-dose exposures (10 cGy) induced genes not affected by high dose (2 Gy), and low-dose genes were associated with unique pathways and functions. The low-dose response had two major components: pathways that are consistently seen across tissues, and pathways that were brain tissue specific. Low-dose genes clustered into a saturated network (p < 10{sup -53}) containing mostly down-regulated genes involving ion channels, long-term potentiation and depression, vascular damage, etc. We identified 9 neural signaling pathways that showed a high degree of concordance in their transcriptional response in mouse brain tissue after low-dose radiation, in the aging human brain (unirradiated), and in brain tissue from patients with Alzheimer's disease. Mice exposed to high-dose radiation did not show these effects and associations. Our findings indicate that the molecular response of the mouse brain within a few hours after low-dose irradiation involves the down-regulation of neural pathways associated with cognitive dysfunctions that are also down regulated in normal human aging and Alzheimer's disease.

  2. Assessment of effectiveness of geologic isolation systems. ARRRG and FOOD: computer programs for calculating radiation dose to man from radionuclides in the environment

    SciTech Connect (OSTI)

    Napier, B.A.; Roswell, R.L.; Kennedy, W.E. Jr.; Strenge, D.L.

    1980-06-01T23:59:59.000Z

    The computer programs ARRRG and FOOD were written to facilitate the calculation of internal radiation doses to man from the radionuclides in the environment and external radiation doses from radionuclides in the environment. Using ARRRG, radiation doses to man may be calculated for radionuclides released to bodies of water from which people might obtain fish, other aquatic foods, or drinking water, and in which they might fish, swim or boat. With the FOOD program, radiation doses to man may be calculated from deposition on farm or garden soil and crops during either an atmospheric or water release of radionuclides. Deposition may be either directly from the air or from irrigation water. Fifteen crop or animal product pathways may be chosen. ARRAG and FOOD doses may be calculated for either a maximum-exposed individual or for a population group. Doses calculated are a one-year dose and a committed dose from one year of exposure. The exposure is usually considered as chronic; however, equations are included to calculate dose and dose commitment from acute (one-time) exposure. The equations for calculating internal dose and dose commitment are derived from those given by the International Commission on Radiological Protection (ICRP) for body burdens and Maximum Permissible Concentration (MPC) of each radionuclide. The radiation doses from external exposure to contaminated farm fields or shorelines are calculated assuming an infinite flat plane source of radionuclides. A factor of two is included for surface roughness. A modifying factor to compensate for finite extent is included in the shoreline calculations.

  3. Lack of benefit of pelvic radiation in prostate cancer patients with a high risk of positive pelvic lymph nodes treated with high-dose radiation

    SciTech Connect (OSTI)

    Vargas, Carlos Enrique [William Beaumont Hospital, Royal Oak, MI (United States); Galalae, Razavan [Kiel University Hospital, Kiel (Germany); Demanes, Jeffrey [California Endocuritherapy Cancer Center, Oakland, CA (United States); Harsolia, Asif [William Beaumont Hospital, Royal Oak, MI (United States); Meldolesi, Elisa [William Beaumont Hospital, Royal Oak, MI (United States); Nuernberg, Nils [Municipal Hospital Kiel, Kiel (Germany); Schour, Lionel [California Endocuritherapy Cancer Center, Oakland, CA (United States); Martinez, Alvaro [William Beaumont Hospital, Royal Oak, MI (United States)]. E-mail: amartinez@beaumont.edu

    2005-12-01T23:59:59.000Z

    Purpose: The use of pelvic radiation for patients with a high risk of lymph node (LN) metastasis (>15%) remains controversial. We reviewed the data at three institutions treating patients with a combination of external-beam radiation therapy and high-dose-rate brachytherapy to address the prognostic implications of the use of the Roach formula and the benefit of pelvic treatment. Methods and Materials: From 1986 to 2003, 1,491 patients were treated with external-beam radiation therapy and high-dose-rate brachytherapy. The Roach formula [2/3 prostate-specific antigen + (Gleason score -6) x 10] could be calculated for 1,357 patients. Group I consisted of patients having a risk of positive LN {<=}15% (n = 761), Group II had a risk >15% and {<=}30% (n = 422), and Group III had a risk of LN disease >30% (n 174). A >15% risk of having positive LN was found in 596 patients and was used to determine the benefit of pelvic radiation. The pelvis was treated at two of the cancer centers (n = 312), whereas at the third center (n = 284) radiation therapy was delivered to the prostate and seminal vesicles alone. Average biologic effective dose was {>=}100 Gy ({alpha}{beta} = 1.2). Biochemical failure was as per the American Society for Therapeutic Radiology and Oncology definition. Statistics included the log-rank test as well as Cox univariate and multivariate analysis. Results: For all 596 patients with a positive LN risk >15%, median follow-up was 4.3 years, with a mean of 4.8 years. For all cases, median follow-up was 4 years and mean follow-up was 4.4 years. Five-year results for the three groups based on their risk of positive LN were significantly different in terms of biochemical failure (p < 0.001), clinical control (p < 0.001), disease-free survival excluding biochemical failure (p < 0.001), cause-specific survival (p < 0.001), and overall survival (p < 0.001). For all patients with a risk of positive LN >15% (n 596), Group II (>15-30% risk), or Group III (>30% risk), no benefit was seen in the 5-year rates of clinical failure, cause-specific survival, or overall survival with pelvic radiation. In the Cox multivariate analysis for cause-specific survival, Gleason score (p = 0.009, hazard ratio [HR] 3.1), T stage (p = 0.03, HR 1.8), and year of treatment (p = 0.05, HR 1.1) were significant. A log-rank test for cause-specific survival for all patients (n = 577) by the use of pelvic radiation was not significant (p = 0.99) accounting for high-dose-rate brachytherapy dose, neoadjuvant hormones, Gleason score, prostate-specific antigen, T stage, and year of treatment as covariates. Conclusions: The use of the Roach formula to stratify patients for clinical and biochemical outcomes is excellent. Pelvic radiation added to high prostate radiation doses did not show a clinical benefit for patients at a high risk of pelvic LN disease (>15%) selected using the Roach formula.

  4. SU-C-12A-03: The Impact of Contrast Medium On Radiation Dose in CT: A Systematic Evaluation Across 58 Patient Models

    SciTech Connect (OSTI)

    Sahbaee, P [NC State University, Raleigh, NC (United States); Samei, E [Duke University Medical Center, Durham, NC (United States); Segars, W [Duke University, Durham, NC (United States)

    2014-06-01T23:59:59.000Z

    Purpose: To assess the effect of contrast medium on radiation dose as a function of time via Monte Carlo simulation from the liver CT scan across a library of 5D XCAT models Methods: A validated Monte Carlo simulation package (PENELOPE) was employed to model a CT system (LightSpeed 64 VCT, GE Healthcare). The radiation dose was estimated from a common abdomen CT examination. The dose estimation was performed on a library of adult extended cardiac-torso (5D XCAT) phantoms (35 male, 23 female, mean age 51.5 years, mean weight 80.2 kg). The 5D XCAT models were created based on patient-specific iodine concentration-time results from our computational contrast medium propagation model for different intravenous injection protocols. To enable a dynamic estimation of radiation dose, each organ in the model was assigned to its own time-concentration curve via the PENELOPE package, material.exe. Using the Monte Carlo, for each scan time point after the injection, 80 million photons were initiated and tracked through the phantoms. Finally, the dose to the liver was tallied from the deposited energy. Results: Monte Carlo simulation results of radiation dose delivered to the liver from the XCAT models indicated up to 30% increase in dose for different time after the administration of contrast medium. Conclusion: The contrast enhancement is employed in over 60% of imaging modalities, which not only remarkably affects the CT image quality, but also increases the radiation dose by as much as 70%. The postinjection multiple acquisition in several enhanced CT protocols, makes the radiation dose increment through the use of contrast medium, an inevitable factor in optimization of these protocols. The relationship between radiation dose and injected contrast medium as a function of time studied in this work allows optimization of contrast administration for vulnerable individuals.

  5. Biological in situ Dose Painting for Image-Guided Radiation Therapy Using Drug-Loaded Implantable Devices

    SciTech Connect (OSTI)

    Cormack, Robert A. [Department of Radiation Oncology, Dana Farber Cancer Institute, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts (United States); Sridhar, Srinivas [Electronics Materials Research Institute, Northeastern University, and Department of Physics, Northeastern University, Boston, Massachusetts (United States); Suh, W. Warren; D'Amico, Anthony V. [Department of Radiation Oncology, Dana Farber Cancer Institute, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts (United States); Makrigiorgos, G. Mike, E-mail: mmakrigiorgos@lroc.harvard.ed [Department of Radiation Oncology, Dana Farber Cancer Institute, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts (United States)

    2010-02-01T23:59:59.000Z

    Purpose: Implantable devices routinely used for increasing spatial accuracy in modern image-guided radiation treatments (IGRT), such as fiducials or brachytherapy spacers, encompass the potential for in situ release of biologically active drugs, providing an opportunity to enhance the therapeutic ratio. We model this new approach for two types of treatment. Methods and Materials: Radiopaque fiducials used in IGRT, or prostate brachytherapy spacers ('eluters'), were assumed to be loaded with radiosensitizer for in situ drug slow release. An analytic function describing the concentration of radiosensitizer versus distance from eluters, depending on diffusion-elimination properties of the drug in tissue, was developed. Tumor coverage by the drug was modeled for tumors typical of lung stereotactic body radiation therapy treatments for various eluter dimensions and drug properties. Six prostate {sup 125}I brachytherapy cases were analyzed by assuming implantation of drug-loaded spacers. Radiosensitizer-induced subvolume boost was simulated from which biologically effective doses for typical radiosensitizers were calculated in one example. Results: Drug distributions from three-dimensional arrangements of drug eluters versus eluter size and drug properties were tabulated. Four radiosensitizer-loaded fiducials provide adequate radiosensitization for {approx}4-cm-diameter lung tumors, thus potentially boosting biologically equivalent doses in centrally located stereotactic body treated lesions. Similarly, multiple drug-loaded spacers provide prostate brachytherapy with flexible shaping of 'biologically equivalent doses' to fit requirements difficult to meet by using radiation alone, e.g., boosting a high-risk region juxtaposed to the urethra while respecting normal tissue tolerance of both the urethra and the rectum. Conclusions: Drug loading of implantable devices routinely used in IGRT provides new opportunities for therapy modulation via biological in situ dose painting.

  6. PSA Response to Neoadjuvant Androgen Deprivation Therapy Is a Strong Independent Predictor of Survival in High-Risk Prostate Cancer in the Dose-Escalated Radiation Therapy Era

    SciTech Connect (OSTI)

    McGuire, Sean E., E-mail: semcguir@mdanderson.org [Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, Texas (United States); Lee, Andrew K. [Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States)] [Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Cerne, Jasmina Z. [Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, Texas (United States)] [Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, Texas (United States); Munsell, Mark F. [Department of Biostatistics, University of Texas MD Anderson Cancer Center, Houston, Texas (United States)] [Department of Biostatistics, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Levy, Lawrence B. [Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States)] [Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Kudchadker, Rajat J. [Department of Radiation Physics, University of Texas MD Anderson Cancer Center, Houston, Texas (United States)] [Department of Radiation Physics, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Choi, Seungtaek L.; Nguyen, Quynh N.; Hoffman, Karen E.; Pugh, Thomas J.; Frank, Steven J. [Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States)] [Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Corn, Paul G.; Logothetis, Christopher J. [Department of Genitourinary Medical Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States)] [Department of Genitourinary Medical Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Kuban, Deborah A. [Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States)] [Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States)

    2013-01-01T23:59:59.000Z

    Purpose: The aim of the study was to evaluate the prognostic value of prostate-specific antigen (PSA) response to neoadjuvant androgen deprivation therapy (ADT) prior to dose-escalated radiation therapy (RT) and long-term ADT in high-risk prostate cancer. Methods and Materials: We reviewed the charts of all patients diagnosed with high-risk prostate cancer and treated with a combination of long-term ADT (median, 24 months) and dose-escalated (median, 75.6 Gy) RT between 1990 and 2007. The associations among patient, tumor, and treatment characteristics with biochemical response to neoadjuvant ADT and their effects on failure-free survival (FFS), time to distant metastasis (TDM), prostate cancer-specific mortality (PCSM) and overall survival (OS) were examined. Results: A total of 196 patients met criteria for inclusion. Median follow-up time for patients alive at last contact was 7.0 years (range, 0.5-18.1 years). Multivariate analysis identified the pre-RT PSA concentration (<0.5 vs {>=}0.5 ng/mL) as a significant independent predictor of FFS (P=.021), TDM (P=.009), PCSM (P=.039), and OS (P=.037). On multivariate analysis, pretreatment PSA (iPSA) and African-American race were significantly associated with failure to achieve a pre-RT PSA of <0.5 ng/mL. Conclusions: For high-risk prostate cancer patients treated with long-term ADT and dose-escalated RT, a pre-RT PSA level {>=}0.5 ng/mL after neoadjuvant ADT predicts for worse survival measures. Both elevated iPSA and African-American race are associated with increased risk of having a pre-RT PSA level {>=}0.5 ng/mL. These patients should be considered for clinical trials that test newer, more potent androgen-depleting therapies such as abiraterone and MDV3100 in combination with radiation.

  7. Evaluation of Radiation Dose Reduction during CT Scans Using Oxide Bismuth and Nano-Barium Sulfate Shields

    E-Print Network [OSTI]

    Seoung, Youl-Hun

    2015-01-01T23:59:59.000Z

    The purpose of the present study was to evaluate radiation dose reduction and image quality during CT scanning by using a new dose reduction fiber sheet (DRFS) with commercially available bismuth shields. These DRFS were composed of nano-barium sulfate (BaSO4), filling the gaps left by the large oxide bismuth (Bi2O3) particle sizes. The radiation dose was measured five times at directionss of 12 o'clock from the center of the polymethyl methacrylate (PMMA) head phantom to calculate an average value using a CT ionization chamber. The image quality measured CT transverse images of the PMMA head phantom depending on X-ray tube voltages and the type of shielding. Two regions of interest in CT transverse images were chosen from the right and left areas under the surface of the PMMA head phantom and from ion chamber holes located at directions of 12 o'clock from the center of the PMMA head phantom. The results of this study showed that the new DRFS shields could reduce dosages to 15.61%, 23.05%, and 22.71% more in ...

  8. Randomized, Multicenter Trial on the Effect of Radiation Therapy on Plantar Fasciitis (Painful Heel Spur) Comparing a Standard Dose With a Very Low Dose: Mature Results After 12 Months' Follow-Up

    SciTech Connect (OSTI)

    Niewald, Marcus, E-mail: marcus.niewald@uks.eu [Department of Radiation Oncology, Saarland University Medical Center, Homburg/Saar (Germany)] [Department of Radiation Oncology, Saarland University Medical Center, Homburg/Saar (Germany); Seegenschmiedt, M. Heinrich [Radiotherapy Center, Hamburg (Germany)] [Radiotherapy Center, Hamburg (Germany); Micke, Oliver [Franziskus Hospital, Bielefeld (Germany)] [Franziskus Hospital, Bielefeld (Germany); Graeber, Stefan [Institute for Medical Biometry, Epidemiology and Medical Informatics, Saarland University Medical Center, Homburg/Saar (Germany)] [Institute for Medical Biometry, Epidemiology and Medical Informatics, Saarland University Medical Center, Homburg/Saar (Germany); Muecke, Ralf [Lippe Hospital, Lemgo (Germany)] [Lippe Hospital, Lemgo (Germany); Schaefer, Vera; Scheid, Christine; Fleckenstein, Jochen; Licht, Norbert; Ruebe, Christian [Department of Radiation Oncology, Saarland University Medical Center, Homburg/Saar (Germany)] [Department of Radiation Oncology, Saarland University Medical Center, Homburg/Saar (Germany)

    2012-11-15T23:59:59.000Z

    Purpose: To conduct a randomized trial of radiation therapy for painful heel spur, comparing a standard dose with a very low dose. Methods and Materials: Sixty-six patients were randomized to receive radiation therapy either with a total dose of 6.0 Gy applied in 6 fractions of 1.0 Gy twice weekly (standard dose) or with a total dose of 0.6 Gy applied in 6 fractions of 0.1 Gy twice weekly (low dose). In all patients lateral opposing 4- to 6-MV photon beams were used. The results were measured using a visual analogue scale, the Calcaneodynia score, and the SF12 health survey. The fundamental phase of the study ended after 3 months, and the follow-up was continued up to 1 year. Patients with insufficient pain relief after 3 months were offered reirradiation with the standard dosage at any time afterward. Results: Of 66 patients, 4 were excluded because of withdrawal of consent or screening failures. After 3 months the results in the standard arm were highly significantly superior compared with those in the low-dose arm (visual analogue scale, P=.001; Calcaneodynia score, P=.027; SF12, P=.045). The accrual of patients was stopped at this point. Further evaluation after 12 months' follow-up showed the following results: (1) highly significant fewer patients were reirradiated in the standard arm compared with the low-dose arm (P<.001); (2) the results of patients in the low-dose arm who were reirradiated were identical to those in the standard arm not reirradiated (reirradiation as a salvage therapy if the lower dose was ineffective); (3) patients experiencing a favorable result after 3 months showed this even after 12 months, and some results even improved further between 3 and 12 months. Conclusions: This study confirms the superior analgesic effect of radiation therapy with 6-Gy doses on painful heel spur even for a longer time period of at least 1 year.

  9. SU-E-I-89: Assessment of CT Radiation Dose and Image Quality for An Automated Tube Potential Selection Algorithm Using Pediatric Anthropomorphic and ACR Phantoms

    SciTech Connect (OSTI)

    Mahmood, U; Erdi, Y; Wang, W [Memorial Sloan Kettering Cancer Center, NY, NY (United States)

    2014-06-01T23:59:59.000Z

    Purpose: To assess the impact of General Electrics automated tube potential algorithm, kV assist (kVa) on radiation dose and image quality, with an emphasis on optimizing protocols based on noise texture. Methods: Radiation dose was assessed by inserting optically stimulated luminescence dosimeters (OSLs) throughout the body of a pediatric anthropomorphic phantom (CIRS). The baseline protocol was: 120 kVp, 80 mA, 0.7s rotation time. Image quality was assessed by calculating the contrast to noise ratio (CNR) and noise power spectrum (NPS) from the ACR CT accreditation phantom. CNRs were calculated according to the steps described in ACR CT phantom testing document. NPS was determined by taking the 3D FFT of the uniformity section of the ACR phantom. NPS and CNR were evaluated with and without kVa and for all available adaptive iterative statistical reconstruction (ASiR) settings, ranging from 0 to 100%. Each NPS was also evaluated for its peak frequency difference (PFD) with respect to the baseline protocol. Results: For the baseline protocol, CNR was found to decrease from 0.460 ± 0.182 to 0.420 ± 0.057 when kVa was activated. When compared against the baseline protocol, the PFD at ASiR of 40% yielded a decrease in noise magnitude as realized by the increase in CNR = 0.620 ± 0.040. The liver dose decreased by 30% with kVa activation. Conclusion: Application of kVa reduces the liver dose up to 30%. However, reduction in image quality for abdominal scans occurs when using the automated tube voltage selection feature at the baseline protocol. As demonstrated by the CNR and NPS analysis, the texture and magnitude of the noise in reconstructed images at ASiR 40% was found to be the same as our baseline images. We have demonstrated that 30% dose reduction is possible when using 40% ASiR with kVa in pediatric patients.

  10. Threshold sensor for high-doses of radiation I. Augustyniak, P. Knapkiewicz, J. Dziuban

    E-Print Network [OSTI]

    Boyer, Edmond

    radiation, HDPE degrades and releases atomic hydrogen. The resulting pressure of hydrogen destroys thin are also observed in experimental infrastructures for example LHC where level of radiation is low but long by family of passive thermo- and photoluminescence indicators or hydrogen pressure dosimeters. In situ

  11. Predictive Models for Regional Hepatic Function Based on 99mTc-IDA SPECT and Local Radiation Dose for Physiologic Adaptive Radiation Therapy

    SciTech Connect (OSTI)

    Wang, Hesheng, E-mail: hesheng@umich.edu [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States); Feng, Mary [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States); Frey, Kirk A. [Department of Radiology, University of Michigan, Ann Arbor, Michigan (United States); Ten Haken, Randall K.; Lawrence, Theodore S. [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States); Cao, Yue [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States); Department of Radiology, University of Michigan, Ann Arbor, Michigan (United States); Department of Biomedical Engineering, University of Michigan, Ann Arbor, Michigan (United States)

    2013-08-01T23:59:59.000Z

    Purpose: High-dose radiation therapy (RT) for intrahepatic cancer is limited by the development of liver injury. This study investigated whether regional hepatic function assessed before and during the course of RT using 99mTc-labeled iminodiacetic acid (IDA) single photon emission computed tomography (SPECT) could predict regional liver function reserve after RT. Methods and Materials: Fourteen patients treated with RT for intrahepatic cancers underwent dynamic 99mTc-IDA SPECT scans before RT, during, and 1 month after completion of RT. Indocyanine green (ICG) tests, a measure of overall liver function, were performed within 1 day of each scan. Three-dimensional volumetric hepatic extraction fraction (HEF) images of the liver were estimated by deconvolution analysis. After coregistration of the CT/SPECT and the treatment planning CT, HEF dose–response functions during and after RT were generated. The volumetric mean of the HEFs in the whole liver was correlated with ICG clearance time. Three models, dose, priori, and adaptive models, were developed using multivariate linear regression to assess whether the regional HEFs measured before and during RT helped predict regional hepatic function after RT. Results: The mean of the volumetric liver HEFs was significantly correlated with ICG clearance half-life time (r=?0.80, P<.0001), for all time points. Linear correlations between local doses and regional HEFs 1 month after RT were significant in 12 patients. In the priori model, regional HEF after RT was predicted by the planned dose and regional HEF assessed before RT (R=0.71, P<.0001). In the adaptive model, regional HEF after RT was predicted by regional HEF reassessed during RT and the remaining planned local dose (R=0.83, P<.0001). Conclusions: 99mTc-IDA SPECT obtained during RT could be used to assess regional hepatic function and helped predict post-RT regional liver function reserve. This could support individualized adaptive radiation treatment strategies to maximize tumor control and minimize the risk of liver damage.

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

    E-Print Network [OSTI]

    Bateman, Sarah Caroline Louisa

    1986-01-01T23:59:59.000Z

    . Nuclear Regulatory Commission provides the criteria under which an in-vivo external probe bioassay program for those occupationally exposed to '- I and '" I should be implemented (USNRC79). This is the basis for the Texas A&M University bioassay program... present in the thyroid. Determination of the radiation absorbed dose to the thyroid gland from a known activity of radioiodine present in the thyroid is necessary from both a safety and regulatory standpoint. Regulatory Guide 8. 20, issued by the U. S...

  13. 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;Radiation Countermeasure Mission Space Radionuclide Threats ­ Am-241 ­ Co-60 ­ Cs-137 ­ I-131 ­ Ir-192 ­ Po

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

    E-Print Network [OSTI]

    Boyer, Edmond

    Power Plants (NPP) and high energy physics facilities as Large Hadron Collider (LHC). All in the world and about 50 under construction, we are all concern about the safety operation of these facilities due to the cumulative absorbed dose. Needless to say that the typical NPP of 3rd generation

  15. SU-E-I-81: Assessment of CT Radiation Dose and Image Quality for An Automated Tube Potential Selection Algorithm Using Adult Anthropomorphic and ACR Phantoms

    SciTech Connect (OSTI)

    Mahmood, U; Erdi, Y; Wang, W [Memorial Sloan Kettering Cancer Center, NY, NY (United States)

    2014-06-01T23:59:59.000Z

    Purpose: To assess the impact of General Electrics (GE) automated tube potential algorithm, kV assist (kVa) on radiation dose and image quality, with an emphasis on optimizing protocols based on noise texture. Methods: Radiation dose was assessed by inserting optically stimulated luminescence dosimeters (OSLs) throughout the body of an adult anthropomorphic phantom (CIRS). The baseline protocol was: 120 kVp, Auto mA (180 to 380 mA), noise index (NI) = 14, adaptive iterative statistical reconstruction (ASiR) of 20%, 0.8s rotation time. Image quality was evaluated by calculating the contrast to noise ratio (CNR) and noise power spectrum (NPS) from the ACR CT accreditation phantom. CNRs were calculated according to the steps described in ACR CT phantom testing document. NPS was determined by taking the 3D FFT of the uniformity section of the ACR phantom. NPS and CNR were evaluated with and without kVa and for all available adaptive iterative statistical reconstruction (ASiR) settings, ranging from 0 to 100%. Each NPS was also evaluated for its peak frequency difference (PFD) with respect to the baseline protocol. Results: The CNR for the adult male was found to decrease from CNR = 0.912 ± 0.045 for the baseline protocol without kVa to a CNR = 0.756 ± 0.049 with kVa activated. When compared against the baseline protocol, the PFD at ASiR of 40% yielded a decrease in noise magnitude as realized by the increase in CNR = 0.903 ± 0.023. The difference in the central liver dose with and without kVa was found to be 0.07%. Conclusion: Dose reduction was insignificant in the adult phantom. As determined by NPS analysis, ASiR of 40% produced images with similar noise texture to the baseline protocol. However, the CNR at ASiR of 40% with kVa fails to meet the current ACR CNR passing requirement of 1.0.

  16. Dose-dependent misrejoining of radiation-induced DNA double-strand breaks in human fibroblasts: Experimental and theoretical study for high and low LET radiation

    E-Print Network [OSTI]

    Rydberg, Bjorn; Cooper, Brian; Cooper, Priscilla K.; Holley, William; Chatterjee, Aloke

    2004-01-01T23:59:59.000Z

    S. Kim, and R. M. Myers. Radiation hybrid mapping: a somaticformulation of dual radiation action. Radiat. Res. 75: 471-High-Linear Energy Transfer Radiation in Human Fibroblasts.

  17. Dose reconstruction for the Urals population. Joint Coordinating Committee on Radiation Effects Research, Project 1.1 -- Final report

    SciTech Connect (OSTI)

    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

    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.

  18. Radiation dose assessments to support evaluations of radiological control levels for recycling or reuse of materials and equipment

    SciTech Connect (OSTI)

    Hill, R.L.; Aaberg, R.L.; Baker, D.A.; Kennedy, W.E. Jr.

    1995-07-01T23:59:59.000Z

    Pacific Northwest Laboratory is providing Environmental Protection Support and Assistance to the USDOE, Office of Environmental Guidance. Air, Water, and Radiation Division. As part of this effort, PNL is collecting data and conducting technical evaluations to support DOE analyses of the feasibility of developing radiological control levels for recycling or reuse of metals, concrete, or equipment containing residual radioactive contamination from DOE operations. The radiological control levels will be risk-based, as developed through a radiation exposure scenario and pathway analysis. The analysis will include evaluation of relevant radionuclides, potential mechanisms of exposure, and both health and non-health-related impacts. The main objective of this report is to develop a methodology for establishing radiological control levels for recycle or reuse. This report provides the results of the radiation exposure scenario and pathway analyses for 42 key radionuclides generated during DOE operations that may be contained in metals or equipment considered for either recycling or reuse. The scenarios and information developed by the IAEA. Application of Exemption Principles to the Recycle and Reuse of Materials from Nuclear Facilities, are used as the initial basis for this study. The analyses were performed for both selected worker populations at metal smelters and for the public downwind of a smelter facility. Doses to the public downwind were estimated using the US (EPA) CAP88-PC computer code with generic data on atmospheric dispersion and population density. Potential non-health-related effects of residual activity on electronics and on film were also analyzed.

  19. Causes of Mortality After Dose-Escalated Radiation Therapy and Androgen Deprivation for High-Risk Prostate Cancer

    SciTech Connect (OSTI)

    Tendulkar, Rahul D., E-mail: tendulr@ccf.org [Department of Radiation Oncology, Taussig Cancer Institute, Cleveland Clinic, Cleveland, Ohio (United States); Hunter, Grant K. [Department of Radiation Oncology, Intermountain Healthcare, Salt Lake City, Utah (United States); Reddy, Chandana A.; Stephans, Kevin L.; Ciezki, Jay P.; Abdel-Wahab, May [Department of Radiation Oncology, Taussig Cancer Institute, Cleveland Clinic, Cleveland, Ohio (United States); Stephenson, Andrew J.; Klein, Eric A. [Department of Urology, Glickman Urological Institute, Cleveland Clinic, Cleveland, Ohio (United States); Mahadevan, Arul [Seacoast Cancer Center New Hampshire, Dover, New Hampshire (United States); Kupelian, Patrick A. [Department of Radiation Oncology, University of California Los Angeles Health System, Los Angeles, California (United States)

    2013-09-01T23:59:59.000Z

    Purpose: Men with high-risk prostate cancer have other competing causes of mortality; however, current risk stratification schema do not account for comorbidities. We aim to identify the causes of death and factors predictive for mortality in this population. Methods and Materials: A total of 660 patients with high-risk prostate cancer were treated with definitive high-dose external beam radiation therapy (?74 Gy) and androgen deprivation (AD) between 1996 and 2009 at a single institution. Cox proportional hazards regression analysis was conducted to determine factors predictive of survival. Results: The median radiation dose was 78 Gy, median duration of AD was 6 months, and median follow-up was 74 months. The 10-year overall survival (OS) was 60.6%. Prostate cancer was the leading single cause of death, with 10-year mortality of 14.1% (95% CI 10.7-17.6), compared with other cancers (8.4%, 95% CI 5.7-11.1), cardiovascular disease (7.3%, 95% CI 4.7-9.9), and all other causes (10.4%, 95% CI 7.2-13.6). On multivariate analysis, older age (HR 1.55, P=.002) and Charlson comorbidity index score (CS) ?1 (HR 2.20, P<.0001) were significant factors predictive of OS, whereas Gleason score, T stage, prostate-specific antigen, duration of AD, radiation dose, smoking history, and body mass index were not. Men younger than 70 years of age with CS = 0 were more likely to die of prostate cancer than any other cause, whereas older men or those with CS ?1 more commonly suffered non-prostate cancer death. The cumulative incidences of prostate cancer-specific mortality were similar regardless of age or comorbidities (P=.60). Conclusions: Men with high-risk prostate cancer are more likely to die of causes other than prostate cancer, except for the subgroup of men younger than 70 years of age without comorbidities. Only older age and presence of comorbidities significantly predicted for OS, whereas prostate cancer- and treatment-related factors did not.

  20. A preliminary model of the circulating blood for use in radiation dose calculations 

    E-Print Network [OSTI]

    Hui, Tsz-Yik Edmond

    1986-01-01T23:59:59.000Z

    . , 1968) "Distribution of Dose in the Body for a Source of Gamma Rays Distributed Uniformly in an Organ, " Oak Rdige National Laboratory, Oak Ridge, TN, ORNL-4168. Folkow B ~ and Neil E ~ g 1971' Circulation (New York: Oxford University Press... Phantom, Oak Ridge National Laboratory, Oak Ridge, TN, ORNL-TM-2250. Wa84 Watson E. E. , Stabin M. G. and Bolch W. E. , 1984, HIRDOSE, Oak Ridge Associated Universities, Oak Ridge/ TN. 53 Va80 van Reenen O. R. , Lotter M. G. , Minnaar P. C. , Heyns A...

  1. A Multi-institutional Clinical Trial of Rectal Dose Reduction via Injected Polyethylene-Glycol Hydrogel During Intensity Modulated Radiation Therapy for Prostate Cancer: Analysis of Dosimetric Outcomes

    SciTech Connect (OSTI)

    Song, Danny Y., E-mail: dsong2@jhmi.edu [Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins University, Baltimore, Maryland (United States); Herfarth, Klaus K.; Uhl, Matthias [Department of Radiation Oncology, University of Heidelberg, Heidelberg (Germany); Eble, Michael J.; Pinkawa, Michael [Department of Radiation Oncology, RWTH Aachen University, Aachen (Germany); Triest, Baukelien van; Kalisvaart, Robin [Department of Radiation Oncology, Netherlands Cancer Institute/Antoni van Leeuwenhoek Ziekenhuis, Amsterdam (Netherlands); Weber, Damien C.; Miralbell, Raymond [Department of Radiation Oncology, Geneva University, Geneva (Switzerland); DeWeese, Theodore L. [Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins University, Baltimore, Maryland (United States); Ford, Eric C. [Department of Radiation Oncology, University of Washington, Seattle, Washington (United States)

    2013-09-01T23:59:59.000Z

    Purpose: To characterize the effect of a prostate-rectum spacer on dose to rectum during external beam radiation therapy for prostate cancer and to assess for factors correlated with rectal dose reduction. Methods and Materials: Fifty-two patients at 4 institutions were enrolled into a prospective pilot clinical trial. Patients underwent baseline scans and then were injected with perirectal spacing hydrogel and rescanned. Intensity modulated radiation therapy plans were created on both scans for comparison. The objectives were to establish rates of creation of ?7.5 mm of prostate-rectal separation, and decrease in rectal V70 of ?25%. Multiple regression analysis was performed to evaluate the associations between preinjection and postinjection changes in rectal V70 and changes in plan conformity, rectal volume, bladder volume, bladder V70, planning target volume (PTV), and postinjection midgland separation, gel volume, gel thickness, length of PTV/gel contact, and gel left-to-right symmetry. Results: Hydrogel resulted in ?7.5-mm prostate-rectal separation in 95.8% of patients; 95.7% had decreased rectal V70 of ?25%, with a mean reduction of 8.0 Gy. There were no significant differences in preinjection and postinjection prostate, PTV, rectal, and bladder volumes. Plan conformities were significantly different before versus after injection (P=.02); plans with worse conformity indexes after injection compared with before injection (n=13) still had improvements in rectal V70. In multiple regression analysis, greater postinjection reduction in V70 was associated with decreased relative postinjection plan conformity (P=.01). Reductions in V70 did not significantly vary by institution, despite significant interinstitutional variations in plan conformity. There were no significant relationships between reduction in V70 and the other characteristics analyzed. Conclusions: Injection of hydrogel into the prostate-rectal interface resulted in dose reductions to rectum for >90% of patients treated. Rectal sparing was statistically significant across a range of 10 to 75 Gy and was demonstrated within the presence of significant interinstitutional variability in plan conformity, target definitions, and injection results.

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

    SciTech Connect (OSTI)

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

    2013-03-01T23:59:59.000Z

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

  3. Radiation Doses to the Public From the Transport of Spent Nuclear Fuel

    SciTech Connect (OSTI)

    Best, R. E.; Maheras, S. J.; Ross, S. S.; Weiner, R.

    2003-02-25T23:59:59.000Z

    This paper reviews issues that have been raised concerning radiological risks and safety of the public exposed to shipments of spent nuclear fuel and high-level radioactive waste to a Yucca Mountain repository. It presents and analyzes the contrasting viewpoints of opponents and proponents, presents facts about radiological exposures and risks, and provides perspective from which to observe the degree of risk that would devolve from the shipments. The paper concludes that the risks to the public's health and safety from being exposed to radiation from the shipments will not be discernable.

  4. Scattering of an ultrashort electromagnetic radiation pulse by an atom in a broad spectral range

    SciTech Connect (OSTI)

    Astapenko, V. A., E-mail: astval@mail.ru [Moscow Institute of Physics and Technology (Russian Federation)

    2011-02-15T23:59:59.000Z

    The scattering of an ultrashort electromagnetic pulse by atomic particles is described using a consistent quantum-mechanical approach taking into account excitation of a target and nondipole electromagnetic interaction, which is valid in a broad spectral range. This approach is applied to the scattering of single- and few-cycle pulses by a multielectron atom and a hydrogen atom. Scattering spectra are obtained for ultrashort pulses of different durations. The relative contribution of 'elastic' scattering of a single-cycle pulse by a hydrogen atom is studied in the high-frequency limit as a function of the carrier frequency and scattering angle.

  5. Outcome of Patients Treated With a Single-Fraction Dose of Palliative Radiation for Cutaneous T-Cell Lymphoma

    SciTech Connect (OSTI)

    Thomas, Tarita O.; Agrawal, Priya [Department of Radiation Oncology, Northwestern University, Robert H. Lurie Comprehensive Cancer Center, Chicago, Illinois (United States)] [Department of Radiation Oncology, Northwestern University, Robert H. Lurie Comprehensive Cancer Center, Chicago, Illinois (United States); Guitart, Joan [Department of Dermatology, Northwestern University, Robert H. Lurie Comprehensive Cancer Center, Chicago, Illinois (United States)] [Department of Dermatology, Northwestern University, Robert H. Lurie Comprehensive Cancer Center, Chicago, Illinois (United States); Rosen, Steven T. [Division of Hematology/Oncology, Department of Medicine, Northwestern University, Robert H. Lurie Comprehensive Cancer Center, Chicago, Illinois (United States)] [Division of Hematology/Oncology, Department of Medicine, Northwestern University, Robert H. Lurie Comprehensive Cancer Center, Chicago, Illinois (United States); Rademaker, Alfred W. [Department of Preventive Medicine, Northwestern University, Robert H. Lurie Comprehensive Cancer Center, Chicago, Illinois (United States)] [Department of Preventive Medicine, Northwestern University, Robert H. Lurie Comprehensive Cancer Center, Chicago, Illinois (United States); Querfeld, Christiane [Department of Medicine/Dermatology Service, Memorial Sloan-Kettering Cancer Center, New York, New York (United States)] [Department of Medicine/Dermatology Service, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Hayes, John P. [Department of Radiation Oncology, Northwestern University, Robert H. Lurie Comprehensive Cancer Center, Chicago, Illinois (United States)] [Department of Radiation Oncology, Northwestern University, Robert H. Lurie Comprehensive Cancer Center, Chicago, Illinois (United States); Kuzel, Timothy M. [Division of Hematology/Oncology, Department of Medicine, Northwestern University, Robert H. Lurie Comprehensive Cancer Center, Chicago, Illinois (United States)] [Division of Hematology/Oncology, Department of Medicine, Northwestern University, Robert H. Lurie Comprehensive Cancer Center, Chicago, Illinois (United States); Mittal, Bharat B., E-mail: bmittal@nmh.org [Department of Radiation Oncology, Northwestern University, Robert H. Lurie Comprehensive Cancer Center, Chicago, Illinois (United States)

    2013-03-01T23:59:59.000Z

    Purpose: Cutaneous T-cell lymphoma (CTCL) is a radiosensitive tumor. Presently, treatment with radiation is given in multiple fractions. The current literature lacks data that support single-fraction treatment for CTCL. This retrospective review assesses the clinical response in patients treated with a single fraction of radiation. Methods and Materials: This study reviewed the records of 58 patients with CTCL, primarily mycosis fungoides, treated with a single fraction of palliative radiation therapy (RT) between October 1991 and January 2011. Patient and tumor characteristics were reviewed. Response rates were compared using Fisher's exact test and multiple logistic regressions. Survival rates were determined using the Kaplan-Meier method. Cost-effectiveness analysis was performed to assess the cost of a single vs a multifractionated treatment regimen. Results: Two hundred seventy individual lesions were treated, with the majority (97%) treated with ?700 cGy; mean follow-up was 41.3 months (range, 3-180 months). Response rate by lesion was assessed, with a complete response (CR) in 255 (94.4%) lesions, a partial response in 10 (3.7%) lesions, a partial response converted to a CR after a second treatment in 4 (1.5%) lesions, and no response in 1 (0.4%) lesion. The CR in lower extremity lesions was lower than in other sites (P=.0016). Lesions treated with photons had lower CR than those treated with electrons (P=.017). Patients with lesions exhibiting large cell transformation and tumor morphology had lower CR (P=.04 and P=.035, respectively). Immunophenotype did not impact response rate (P=.23). Overall survival was significantly lower for patients with Sézary syndrome (P=.0003) and erythroderma (P<.0001). The cost of multifractionated radiation was >200% higher than that for single-fraction radiation. Conclusions: A single fraction of 700 cGy-800 cGy provides excellent palliation for CTCL lesions and is cost effective and convenient for the patient.

  6. 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 (OSTI)

    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

    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.

  7. Variations of the hypoxic fraction in the SCC VII tumors after single dose and during fractionated radiation therapy: Assessment without anesthesia or physical restraint of mice

    SciTech Connect (OSTI)

    Kitakabu, Y.; Shibamoto, Y.; Sasai, K.; Ono, K.; Abe, M. (Kyoto Univ. (Japan))

    1991-04-01T23:59:59.000Z

    Variations of the hypoxic fraction (HF) after single dose (13 Gy or 4 Gy) and during fractionated (5 fractions of 4 Gy, 1 or 2 fractions per day) radiation therapy were studied in SCC VII tumors implanted subcutaneously in the hind legs of C3H/He/Jms mice using the paired survival curve method. Whole-body irradiation was delivered to tumor-bearing mice without anesthesia or physical restraint, because both are known to increase the HF artificially. The HF decreased after a single 13 Gy dose in a biphasic fashion: extremely rapidly within 1 hr and comparatively slowly during the following 12-72 hr. On the other hand, nearly no fall of HF was observed in 24 hr following a single 4 Gy dose. Also, reoxygenation was found to occur more rapidly in the interfraction period as the number of fractions of 4 Gy increased irrespective of differences of interfraction time. However, the HF just before each radiation fraction was significantly higher than the pretreatment level for both fractionated regimens. Thus, the reoxygenation patterns observed after single low and high doses of irradiation were different from each other, and reoxygenation in each interfraction period did not always proceed in a similar manner to that after single low dose irradiation. Reoxygenation was facilitated as fractionated radiation therapy proceeded, but it was not sufficient for the HF to remain at a level comparable to that before irradiation.

  8. Prognostic Significance of Carbohydrate Antigen 19-9 in Unresectable Locally Advanced Pancreatic Cancer Treated With Dose-Escalated Intensity Modulated Radiation Therapy and Concurrent Full-Dose Gemcitabine: Analysis of a Prospective Phase 1/2 Dose Escalation Study

    SciTech Connect (OSTI)

    Vainshtein, Jeffrey M., E-mail: jvainsh@med.umich.edu [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States); Schipper, Matthew [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States)] [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States); 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); Lawrence, Theodore S. [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States)] [Department of Radiation Oncology, 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); 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); Khan, Gazala [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); 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); Ben-Josef, Edgar [Department of Radiation Oncology, University of Pennsylvania, Philadelphia, Pennsylvania (United States)] [Department of Radiation Oncology, University of Pennsylvania, Philadelphia, Pennsylvania (United States)

    2013-05-01T23:59:59.000Z

    Purpose: Although established in the postresection setting, the prognostic value of carbohydrate antigen 19-9 (CA19-9) in unresectable locally advanced pancreatic cancer (LAPC) is less clear. We examined the prognostic utility of CA19-9 in patients with unresectable LAPC treated on a prospective trial of intensity modulated radiation therapy (IMRT) dose escalation with concurrent gemcitabine. Methods and Materials: Forty-six patients with unresectable LAPC were treated at the University of Michigan on a phase 1/2 trial of IMRT dose escalation with concurrent gemcitabine. CA19-9 was obtained at baseline and during routine follow-up. Cox models were used to assess the effect of baseline factors on freedom from local progression (FFLP), distant progression (FFDP), progression-free survival (PFS), and overall survival (OS). Stepwise forward regression was used to build multivariate predictive models for each endpoint. Results: Thirty-eight patients were eligible for the present analysis. On univariate analysis, baseline CA19-9 and age predicted OS, CA19-9 at baseline and 3 months predicted PFS, gross tumor volume (GTV) and black race predicted FFLP, and CA19-9 at 3 months predicted FFDP. On stepwise multivariate regression modeling, baseline CA19-9, age, and female sex predicted OS; baseline CA19-9 and female sex predicted both PFS and FFDP; and GTV predicted FFLP. Patients with baseline CA19-9 ?90 U/mL had improved OS (median 23.0 vs 11.1 months, HR 2.88, P<.01) and PFS (14.4 vs 7.0 months, HR 3.61, P=.001). CA19-9 progression over 90 U/mL was prognostic for both OS (HR 3.65, P=.001) and PFS (HR 3.04, P=.001), and it was a stronger predictor of death than either local progression (HR 1.46, P=.42) or distant progression (HR 3.31, P=.004). Conclusions: In patients with unresectable LAPC undergoing definitive chemoradiation therapy, baseline CA19-9 was independently prognostic even after established prognostic factors were controlled for, whereas CA19-9 progression strongly predicted disease progression and death. Future trials should stratify by baseline CA19-9 and incorporate CA19-9 progression as a criterion for progressive disease.

  9. Tissue responses to low protracted doses of high let radiations or photons: Early and late damage relevant to radio-protective countermeasures

    SciTech Connect (OSTI)

    Ainsworth, E.J.; Afzal, S.M.J.; Crouse, D.A.; Hanson, W.R.; Fry, R.J.M.

    1988-01-01T23:59:59.000Z

    Early and late murine tissue responses to single or fractionated low doses of heavy charged particles, fission-spectrum neutrons or gamma rays are considered. Damage to the hematopoietic system is emphasized, but results on acute lethality, host response to challenge with transplanted leukemia cells and life-shortening are presented. Low dose rates per fraction were used in some neutron experiments. Split-dose lethality studies (LD 50/30) with fission neutrons indicated greater accumulation of injury during a 9 fraction course (over 17 days) than was the case for ..gamma..-radiation. When total doses of 96 or 247 cGy of neutrons or ..gamma.. rays were given as a single dose or in 9 fractions, a significant sparing effect on femur CFU-S depression was observed for both radiation qualities during the first 11 days, but there was not an earlier return to normal with dose fractionation. During the 9 fraction sequence, a significant sparing effect of low dose rate on CFU-S depression was observed in both neutron and ..gamma..-irradiated mice. CFU-S content at the end of the fractionation sequence did not correlate with measured LD 50/30. Sustained depression of femur and spleen CFU-S and a significant thrombocytopenia were observed when a total neutron dose of 240 cGy was given in 72 fractions over 24 weeks at low dose rates. The temporal aspects of CFU-S repopulation were different after a single versus fractionated neutron doses. The sustained reduction in the size of the CFU-S population was accompanied by an increase in the fraction in DNA synthesis. The proliferation characteristics and effects of age were different for radial CFU-S population closely associated with bone, compared with the axial population that can be readily aspirated from the femur. In aged irradiated animals, the CFU-S proliferation/redistribution response to typhoid vaccine showed both an age and radiation effect. 63 refs., 6 figs., 7 tabs.

  10. 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 (OSTI)

    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, Skåne University Hospital, Lund (Sweden); Engström, 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, Øyvind 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

    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 dose–response 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.

  11. Radiation leukaemogenesis at low doses DE-FG02-05 ER 63947 Final Technical Report 15 May 2005 â?? 14 May 2010

    SciTech Connect (OSTI)

    Simon Bouffler; Christophe Badie; Natalie Brown; Rosemary Finnon

    2010-07-28T23:59:59.000Z

    This report provides a full summary of the results obtained under grant DE-FG02-05ER63947, Radiation Leukaemogenesis at low doses. The studies employed an experimental model of radiation leukaemogenesis with the main aim of identifying key events that convert normal cells into leukaemic cells follwoing exposure to radiation. Important aspect of the work was to understand dose-response relationships and time course relationships for leakaemogenis events. The studies performed provided evidence for direct radiation-induced losses of the Sfpi1/PU.1 gene being critical for induction of the disease. No threshold below 0.1 Gy in the induction of the gene losses was observed. The critical cell type in which the myeloid lekaemias arise has been identified and point mutations in the Sfpi1/PU.1 gene are common in leukaemias. The consequences of the genetic losses and mutation have been examined and these provide evidence of a disruption of differentiation in leukaemic cells. Additional pathways to leukaemogenesis have been identified also. Overall the study provides quantitiative data suitable for testing approaches to modelling of leukaemia rosk at low doses.

  12. An Overview of the Regulation of Low Dose Radiation in the Nuclear and Non-nuclear Industries

    SciTech Connect (OSTI)

    Menon, Shankar; Valencia, Luis; Teunckens, Lucien

    2003-02-27T23:59:59.000Z

    Now that increasing numbers of nuclear power stations are reaching the end of their commercially useful lives, the management of the large quantities of very low level radioactive material that arises during their decommissioning has become a major subject of discussion, with very significant economic implications. Much of this material can, in an environmentally advantageous manner, be recycled for reuse without radiological restrictions. Much larger quantities--2-3 orders of magnitude larger--of material, radiologically similar to the candidate material for recycling from the nuclear industry, arise in non-nuclear industries like coal, fertilizer, oil and gas, mining, etc. In such industries, naturally occurring radioactivity is artificially concentrated in products, by-products or waste to form TENORM (Technologically Enhanced Naturally Occurring Radioactive Material). It is only in the last decade that the international community has become aware of the prevalence of TENORM, specially the activity levels and quantities arising in so many non-nuclear industries. The first reaction of international organizations seems to have been to propose different standards for the nuclear and non-nuclear industries, with very stringent release criteria for radioactive material from the regulated nuclear industry and up to thirty to a hundred times more liberal criteria for the release/exemption of TENORM from the as yet unregulated non-nuclear industries. There are significant strategic issues that need to be discussed and resolved. Some examples of these are: - Disposal aspects of long-lived nuclides, - The use of radioactive residues in building materials, - Commercial aspects of differing and discriminating criteria in competing power industries in a world of deregulated electric power production. Of even greater importance is the need for the discussion of certain basic issues, such as - The quantitative risk levels of exposure to ionizing radiation, - The need for in-depth studies on populations of the naturally high background dose level areas of the world, - The validity of the various calculation codes currently used to arrive at mass specific clearance levels for redundant material. The paper discusses these and other strategic issues regarding the management of redundant low radiation material from both the nuclear and non-nuclear industries, underlining the need for consistency in regulatory treatment.

  13. Low Dose Radiation

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville PowerCherries 82981-1cnHigh SchoolIn12electron 9 5LetLooking5investsLouisPrepared:Stability

  14. RADIATION SENSITIVITY & PROCESSING OF DNA DAMAGE FOLLOWING LOW DOSES OF GAMMA-RAY ALPHA PARTICLES & HZE IRRADIATION OF NORMAL DSB REPAIR DEFICIENT CELLS

    SciTech Connect (OSTI)

    O'Neil, Peter

    2009-05-15T23:59:59.000Z

    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.

  15. 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]

    Chichkov, Igor

    1999-01-01T23:59:59.000Z

    for broad parallel beams of external photon radiation. The mathematical model of the human body that was used for this study was a hermaphroditic phantom developed at the Oak Ridge National Laboratory (Eckerman et at. 1996). Adding a layer of soft tissue...

  16. 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]

    Chichkov, Igor

    1999-01-01T23:59:59.000Z

    for broad parallel beams of external photon radiation. The mathematical model of the human body that was used for this study was a hermaphroditic phantom developed at the Oak Ridge National Laboratory (Eckerman et at. 1996). Adding a layer of soft tissue...

  17. American Society for Radiation Oncology (ASTRO) and American College of Radiology (ACR) Practice Guideline for the Performance of High-Dose-Rate Brachytherapy

    SciTech Connect (OSTI)

    Erickson, Beth A. [Department of Radiation Oncology, Medical College of Wisconsin, Milwaukee, WI (United States); Demanes, D. Jeffrey [Department of Radiation Oncology , University of California, Los Angeles, CA (United States); Ibbott, Geoffrey S. [Radiological Physics Center, MD Anderson Cancer Center, Houston, TX (United States); Hayes, John K. [Gamma West Brachytherapy, Salt Lake City, UT (United States); Hsu, I-Chow J. [Department of Radiation Oncology, University of California San Francisco, San Francisco, CA (United States); Morris, David E. [Department of Radiation Oncology, University of North Carolina, Chapel Hill, NC (United States); Rabinovitch, Rachel A. [Department of Radiation Oncology, University of Colorado Denver, Aurora, CO (United States); Tward, Jonathan D. [Department of Radiation Oncology, Huntsman Cancer Institute, Salt Lake City, UT (United States); Rosenthal, Seth A. [Radiation Oncology Centers, Radiological Associates of Sacramento, Sacramento, CA (United States)

    2011-03-01T23:59:59.000Z

    High-Dose-Rate (HDR) brachytherapy is a safe and efficacious treatment option for patients with a variety of different malignancies. Careful adherence to established standards has been shown to improve the likelihood of procedural success and reduce the incidence of treatment-related morbidity. A collaborative effort of the American College of Radiology (ACR) and American Society for Therapeutic Radiation Oncology (ASTRO) has produced a practice guideline for HDR brachytherapy. The guideline defines the qualifications and responsibilities of all the involved personnel, including the radiation oncologist, physicist and dosimetrists. Review of the leading indications for HDR brachytherapy in the management of gynecologic, thoracic, gastrointestinal, breast, urologic, head and neck, and soft tissue tumors is presented. Logistics with respect to the brachytherapy implant procedures and attention to radiation safety procedures and documentation are presented. Adherence to these practice guidelines can be part of ensuring quality and safety in a successful HDR brachytherapy program.

  18. A Monte Carlo Study of the Relationship between the Time Structures of Prompt Gammas and in vivo Radiation Dose in Proton Therapy

    E-Print Network [OSTI]

    Shin, Wook-Geun; Shin, Jae-Ik; Jeong, Jong Hwi; Lee, Se Byeong

    2015-01-01T23:59:59.000Z

    For the in vivo range verification in proton therapy, it has been tried to measure the spatial distribution of the prompt gammas generated by the proton-induced interactions with the close relationship with the proton dose distribution. However, the high energy of the prompt gammas and background gammas are still problematic in measuring the distribution. In this study, we suggested a new method determining the in vivo range by utilizing the time structure of the prompt gammas formed with the rotation of a range modulation wheel (RMW) in the passive scattering proton therapy. To validate the Monte Carlo code simulating the proton beam nozzle, axial percent depth doses (PDDs) were compared with the measured PDDs with the varying beam range of 4.73-24.01 cm. And the relationship between the proton dose rate and the time structure of the prompt gammas was assessed and compared in the water phantom. The results of the PDD showed accurate agreement within the relative errors of 1.1% in the distal range and 2.9% in...

  19. Topographic Effects on Ambient Dose Equivalent Rates from Radiocesium Fallout

    E-Print Network [OSTI]

    Malins, Alex; Machida, Masahiko; Saito, Kimiaki

    2015-01-01T23:59:59.000Z

    Land topography can affect air radiation dose rates by locating radiation sources closer to, or further, from detector locations when compared to perfectly flat terrain. Hills and slopes can also shield against the propagation of gamma rays. To understand the possible magnitude of topographic effects on air dose rates, this study presents calculations for ambient dose equivalent rates at a range of heights above the ground for varying land topographies. The geometries considered were angled ground at the intersection of two planar surfaces, which is a model for slopes neighboring flat land, and a simple conical geometry, representing settings from hilltops to valley bottoms. In each case the radiation source was radioactive cesium fallout, and the slope angle was varied systematically to determine the effect of topography on the air dose rate. Under the assumption of homogeneous fallout across the land surface, and for these geometries and detector locations, the dose rates at high altitudes are more strongly...

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

    SciTech Connect (OSTI)

    Damast, Shari, E-mail: shari.damast@yale.edu [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); Alektiar, Kaled M. [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); Goldfarb, Shari [Department of Medicine, Memorial Sloan-Kettering Cancer Center, New York, New York (United States)] [Department of Medicine, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Eaton, Anne; Patil, Sujata [Department of Epidemiology and Biostatistics, Memorial Sloan-Kettering Cancer Center, New York, New York (United States)] [Department of Epidemiology and Biostatistics, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Mosenkis, Jeffrey [Department of Comparative Human Development, University of Chicago, Chicago, Illinois (United States)] [Department of Comparative Human Development, University of Chicago, Chicago, Illinois (United States); Bennett, Antonia [Department of Epidemiology and Biostatistics, Memorial Sloan-Kettering Cancer Center, New York, New York (United States)] [Department of Epidemiology and Biostatistics, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Atkinson, Thomas [Department of Psychiatry, Memorial Sloan-Kettering Cancer Center, New York, New York (United States)] [Department of Psychiatry, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Jewell, Elizabeth; Leitao, Mario; Barakat, Richard; Carter, Jeanne [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); Basch, Ethan [Department of Epidemiology and Biostatistics, Memorial Sloan-Kettering Cancer Center, New York, New York (United States)] [Department of Epidemiology and Biostatistics, Memorial Sloan-Kettering Cancer Center, New York, New York (United States)

    2012-10-01T23:59:59.000Z

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

  1. Postoperative Nomogram Predicting the 9-Year Probability of Prostate Cancer Recurrence After Permanent Prostate Brachytherapy Using Radiation Dose as a Prognostic Variable

    SciTech Connect (OSTI)

    Potters, Louis, E-mail: LPotters@nshs.ed [Department of Radiation Medicine, North Shore Long Island Jewish Health System, New Hyde Park, NY (United States); Roach, Mack [Departments of Radiation Oncology and Urology, University of California at San Francisco, San Francisco, CA (United States); Davis, Brian J. [Department of Radiation Oncology, Mayo Clinic, Rochester, MN (United States); Stock, Richard G. [Department of Radiation Oncology, Mount Sinai School of Medicine, New York, NY (United States); Ciezki, Jay P. [Department of Radiation Oncology, Cleveland Clinic, Cleveland, OH (United States); Zelefsky, Michael J. [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, NY (United States); Stone, Nelson N. [Department of Urology, Mount Sinai School of Medicine, New York, NY (United States); Fearn, Paul A. [Department of Urology, Memorial Sloan-Kettering Cancer Center, New York, NY (United States); Yu Changhong [Glickman Urological Institute and the Department of Quantitative Health Sciences, Cleveland Clinic, Cleveland, OH (United States); Shinohara, Katsuto [Departments of Radiation Oncology and Urology, University of California at San Francisco, San Francisco, CA (United States); Kattan, Michael W. [Glickman Urological Institute and the Department of Quantitative Health Sciences, Cleveland Clinic, Cleveland, OH (United States)

    2010-03-15T23:59:59.000Z

    Purpose: To report a multi-institutional outcomes study on permanent prostate brachytherapy (PPB) to 9 years that includes postimplant dosimetry, to develop a postimplant nomogram predicting biochemical freedom from recurrence. Methods and Materials: Cox regression analysis was used to model the clinical information for 5,931 patients who underwent PPB for clinically localized prostate cancer from six centers. The model was validated against the dataset using bootstrapping. Disease progression was determined using the Phoenix definition. The biological equivalent dose was calculated from the minimum dose to 90% of the prostate volume (D90) and external-beam radiotherapy dose using an alpha/beta of 2. Results: The 9-year biochemical freedom from recurrence probability for the modeling set was 77% (95% confidence interval, 73-81%). In the model, prostate-specific antigen, Gleason sum, isotope, external beam radiation, year of treatment, and D90 were associated with recurrence (each p < 0.05), whereas clinical stage was not. The concordance index of the model was 0.710. Conclusion: A predictive model for a postimplant nomogram for prostate cancer recurrence at 9-years after PPB has been developed and validated from a large multi-institutional database. This study also demonstrates the significance of implant dosimetry for predicting outcome. Unique to predictive models, these nomograms may be used a priori to calculate a D90 that likely achieves a desired outcome with further validation. Thus, a personalized dose prescription can potentially be calculated for each patient.

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

    SciTech Connect (OSTI)

    Jian Li

    2012-11-07T23:59:59.000Z

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

  3. Radiation damage by neutrons to plastic scintillators

    SciTech Connect (OSTI)

    Buss, G.; Dannemann, A.; Holm, U.; Wick, K. [Univ. Hamburg (Germany). Inst. fuer Experimentalphysik] [Univ. Hamburg (Germany). Inst. fuer Experimentalphysik

    1995-08-01T23:59:59.000Z

    Polystyrene based scintillator SCSN38, wavelength shifter Y7 with polymethylmethacrylate matrix and pure PM-MA light guide GS218 have been irradiated in the mixed radiation field of a pool reactor. About 77% of the dose released in SCSN38 was caused by the {gamma}-field, 23% by fast neutrons. The total dose ranged from 2 to 105 kGy. The dose measurements were made using alanine dosimeters. Transmission and fluorescence of the samples have been measured before and several times after irradiation. The radiation damage results shown o differences to irradiations in pure {gamma}-fields with corresponding released doses.

  4. SU-E-I-82: Improving CT Image Quality for Radiation Therapy Using Iterative Reconstruction Algorithms and Slightly Increasing Imaging Doses

    SciTech Connect (OSTI)

    Noid, G; Chen, G; Tai, A; Li, X [Department of Radiation Oncology, Medical College of Wisconsin, Milwaukee, WI (United States)

    2014-06-01T23:59:59.000Z

    Purpose: Iterative reconstruction (IR) algorithms are developed to improve CT image quality (IQ) by reducing noise without diminishing spatial resolution or contrast. For CT in radiation therapy (RT), slightly increasing imaging dose to improve IQ may be justified if it can substantially enhance structure delineation. The purpose of this study is to investigate and to quantify the IQ enhancement as a result of increasing imaging doses and using IR algorithms. Methods: CT images were acquired for phantoms, built to evaluate IQ metrics including spatial resolution, contrast and noise, with a variety of imaging protocols using a CT scanner (Definition AS Open, Siemens) installed inside a Linac room. Representative patients were scanned once the protocols were optimized. Both phantom and patient scans were reconstructed using the Sinogram Affirmed Iterative Reconstruction (SAFIRE) and the Filtered Back Projection (FBP) methods. IQ metrics of the obtained CTs were compared. Results: IR techniques are demonstrated to preserve spatial resolution as measured by the point spread function and reduce noise in comparison to traditional FBP. Driven by the reduction in noise, the contrast to noise ratio is doubled by adopting the highest SAFIRE strength. As expected, increasing imaging dose reduces noise for both SAFIRE and FBP reconstructions. The contrast to noise increases from 3 to 5 by increasing the dose by a factor of 4. Similar IQ improvement was observed on the CTs for selected patients with pancreas and prostrate cancers. Conclusion: The IR techniques produce a measurable enhancement to CT IQ by reducing the noise. Increasing imaging dose further reduces noise independent of the IR techniques. The improved CT enables more accurate delineation of tumors and/or organs at risk during RT planning and delivery guidance.

  5. Weldon Spring historical dose estimate

    SciTech Connect (OSTI)

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

    1986-07-01T23:59:59.000Z

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

  6. Relative Biologic Effects of Low-Dose-Rate {alpha}-Emitting {sup 227}Th-Rituximab and {beta}-Emitting {sup 90}Y-Tiuexetan-Ibritumomab Versus External Beam X-Radiation

    SciTech Connect (OSTI)

    Dahle, Jostein [Department of Radiation Biology, Norwegian Radium Hospital, Montebello, Oslo (Norway)], E-mail: jostein.dahle@rr-research.no; Bruland, Oyvind S. [University of Oslo and Department of Oncology, Norwegian Radium Hospital, Montebello, Oslo (Norway); Larsen, Roy H. [Department of Radiation Biology, The Norwegian Radium Hospital, Montebello, Oslo (Norway)

    2008-09-01T23:59:59.000Z

    Purpose: To determine the relative biologic effects (RBE) of {alpha}-particle radiation from {sup 227}Th-rituximab and of {beta}-radiation from {sup 90}Y-tiuexetan-ibritumomab (Zevalin) compared with external beam X-radiation in the Raji lymphoma xenograft model. Methods and Materials: Radioimmunoconjugates were administered intravenously in nude mice with Raji lymphoma xenografts at different levels of activity. Absorbed dose to tumor was estimated by separate biodistribution experiments for {sup 227}Th-rituximab and Zevalin. Tumor growth was measured two to three times per week after injection or X-radiation. Treatment-induced increase in growth delay to reach tumor volumes of 500 and 1,000 mm{sup 3}, respectively, was used as an end point. Results: The absorbed radiation dose-rate in tumor was slightly more than 0.1 Gy/d for the first week following injection of {sup 227}Th-rituximab, and thereafter gradually decreased to 0.03 Gy/d at 21 days after injection. For treatment with Zevalin the maximum dose-rate in tumor was achieved already 6 h after injection (0.2 Gy/d), and thereafter decreased to 0.01 Gy/d after 7 days. The relative biologic effect was between 2.5 and 7.2 for {sup 227}Th-rituximab and between 1 and 1.3 for Zevalin. Conclusions: Both at low doses and low-dose-rates, the {sup 227}Th-rituximab treatment was more effective per absorbed radiation dose unit than the two other treatments. The considerable effect at low doses suggests that the best way to administer low-dose-rates, {alpha}-emitting radioimmunoconjugates is via multiple injections.

  7. Internal dose following a major nuclear war

    SciTech Connect (OSTI)

    Peterson, K.R.; Shapiro, C.S. (Lawrence Livermore National Laboratory, Livermore, CA (Unites States))

    1992-01-01T23:59:59.000Z

    The PATHWAY model results were used, in conjunction with a hypothetical major nuclear attack on the U.S., to arrive at the ratio of internal to external dose for humans from early (48 h) fallout. Considered were the four nuclides (137Cs, 89Sr, 90Sr, 131I) that account for most of the reconstructed whole-body committed equivalent dose from internal radiation in people who lived downwind of the Nevada Test Site during atmospheric tests. Effects of climate perturbations (the 'nuclear winter' effect) on food crops were considered. These could increase internal dose estimates, depending on the severity of the climate perturbations. Internal and external doses to humans for 10 locations within the U.S. have been calculated, with varying local conditions and varying assumption about their shelters. The estimated 50-y internal dose commitment ranged from 0.0-0.17 Sv, the 48-h external dose from 0.15-4.6 Sv. The resultant ratios of internal to external committed dose received in the first months (until food transport was restored) varied from less than 0.01 to about 0.2. In all cases examined, the total dose from early fallout was found to be dominated by the external dose.

  8. Randomized Noninferiority Trial of Reduced High-Dose Volume Versus Standard Volume Radiation Therapy for Muscle-Invasive Bladder Cancer: Results of the BC2001 Trial (CRUK/01/004)

    SciTech Connect (OSTI)

    Huddart, Robert A., E-mail: robert.huddart@icr.ac.uk [Institute of Cancer Research, Royal Marsden NHSFT (National Health Service Foundation Trust) (United Kingdom); Hall, Emma [Institute of Cancer Research (United Kingdom); Hussain, Syed A. [University of Liverpool (United Kingdom); Jenkins, Peter [Gloucestershire Hospitals NHSFT (United Kingdom); Rawlings, Christine [South Devon Healthcare NHSFT (United Kingdom); Tremlett, Jean [Brighton and Sussex University Hospitals (United Kingdom); Crundwell, Malcolm [Royal Devon and Exeter NHSFT (United Kingdom); Adab, Fawzi A. [University Hospital of North Staffordshire NHS Trust (United Kingdom); Sheehan, Denise [Royal Devon and Exeter NHSFT (United Kingdom); Syndikus, Isabel [Clatterbridge Cancer Centre NHSFT (United Kingdom); Hendron, Carey [University of Birmingham (United Kingdom); Lewis, Rebecca; Waters, Rachel [Institute of Cancer Research (United Kingdom); James, Nicholas D. [University of Birmingham (United Kingdom)

    2013-10-01T23:59:59.000Z

    Purpose: To test whether reducing radiation dose to uninvolved bladder while maintaining dose to the tumor would reduce side effects without impairing local control in the treatment of muscle-invasive bladder cancer. Methods and Materials: In this phase III multicenter trial, 219 patients were randomized to standard whole-bladder radiation therapy (sRT) or reduced high-dose volume radiation therapy (RHDVRT) that aimed to deliver full radiation dose to the tumor and 80% of maximum dose to the uninvolved bladder. Participants were also randomly assigned to receive radiation therapy alone or radiation therapy plus chemotherapy in a partial 2 × 2 factorial design. The primary endpoints for the radiation therapy volume comparison were late toxicity and time to locoregional recurrence (with a noninferiority margin of 10% at 2 years). Results: Overall incidence of late toxicity was less than predicted, with a cumulative 2-year Radiation Therapy Oncology Group grade 3/4 toxicity rate of 13% (95% confidence interval 8%, 20%) and no statistically significant differences between groups. The difference in 2-year locoregional recurrence free rate (RHDVRT ? sRT) was 6.4% (95% confidence interval ?7.3%, 16.8%) under an intention to treat analysis and 2.6% (?12.8%, 14.6%) in the “per-protocol” population. Conclusions: In this study RHDVRT did not result in a statistically significant reduction in late side effects compared with sRT, and noninferiority of locoregional control could not be concluded formally. However, overall low rates of clinically significant toxicity combined with low rates of invasive bladder cancer relapse confirm that (chemo)radiation therapy is a valid option for the treatment of muscle-invasive bladder cancer.

  9. Hypofractionated High-Dose Radiation Therapy for Prostate Cancer: Long-Term Results of a Multi-Institutional Phase II Trial

    SciTech Connect (OSTI)

    Fonteyne, Valerie, E-mail: valerie.fonteyne@uzgent.be [Department of Radiotherapy, Ghent University Hospital, Ghent (Belgium)] [Department of Radiotherapy, Ghent University Hospital, Ghent (Belgium); Soete, Guy [Department of Radiotherapy, Universitair Ziekenhuis Brussels, Jette (Belgium)] [Department of Radiotherapy, Universitair Ziekenhuis Brussels, Jette (Belgium); Arcangeli, Stefano [Department of Radiotherapy, Regina Elena National Cancer Institute, Rome (Italy)] [Department of Radiotherapy, Regina Elena National Cancer Institute, Rome (Italy); De Neve, Wilfried [Department of Radiotherapy, Ghent University Hospital, Ghent (Belgium)] [Department of Radiotherapy, Ghent University Hospital, Ghent (Belgium); Rappe, Bernard [Department of Urology, Algemeen Stedelijk Ziekenhuis, Aalst (Belgium)] [Department of Urology, Algemeen Stedelijk Ziekenhuis, Aalst (Belgium); Storme, Guy [Department of Radiotherapy, Universitair Ziekenhuis Brussels, Jette (Belgium)] [Department of Radiotherapy, Universitair Ziekenhuis Brussels, Jette (Belgium); Strigari, Lidia [Laboratory of Medical Physics and Expert Systems, Regina Elena National Cancer Institute, Rome (Italy)] [Laboratory of Medical Physics and Expert Systems, Regina Elena National Cancer Institute, Rome (Italy); Arcangeli, Giorgio [Department of Radiotherapy, Regina Elena National Cancer Institute, Rome (Italy)] [Department of Radiotherapy, Regina Elena National Cancer Institute, Rome (Italy); De Meerleer, Gert [Department of Radiotherapy, Ghent University Hospital, Ghent (Belgium)] [Department of Radiotherapy, Ghent University Hospital, Ghent (Belgium)

    2012-11-15T23:59:59.000Z

    Purpose: To report late gastrointestinal (GI) and genitourinary (GU) toxicity, biochemical and clinical outcomes, and overall survival after hypofractionated radiation therapy for prostate cancer (PC). Methods and Materials: Three institutions included 113 patients with T1 to T3N0M0 PC in a phase II study. Patients were treated with 56 Gy in 16 fractions over 4 weeks. Late toxicity was scored using Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer criteria extended with additional symptoms. Biochemical outcome was reported according to the Phoenix definition for biochemical failure. Results: The incidence of late GI and GU toxicity was low. The 3-year actuarial risk of developing late GU and GI toxicity of grade {>=}2 was 13% and 8% respectively. Five-year biochemical non-evidence of disease (bNED) was 94%. Risk group, T stage, and deviation from planned hormone treatment were significant predictive factors for bNED. Deviation from hormone treatment remained significant in multivariate analysis. Five-year clinical non evidence of disease and overall survival was 95% and 91% respectively. No patient died from PC. Conclusions: Hypofractionated high-dose radiation therapy is a valuable treatment option for patients with PC, with excellent biochemical and clinical outcome and low toxicity.

  10. Shared Dosimetry Error in Epidemiological Dose-Response Analyses

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

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

    2015-03-23T23:59:59.000Z

    Radiation dose reconstruction systems for large-scale epidemiological studies are sophisticated both in providing estimates of dose and in representing dosimetry uncertainty. For example, a computer program was used by the Hanford Thyroid Disease Study to provide 100 realizations of possible dose to study participants. The variation in realizations reflected the range of possible dose for each cohort member consistent with the data on dose determinates in the cohort. Another example is the Mayak Worker Dosimetry System 2013 which estimates both external and internal exposures and provides multiple realizations of "possible" dose history to workers given dose determinants. This paper takesmore »up the problem of dealing with complex dosimetry systems that provide multiple realizations of dose in an epidemiologic analysis. In this paper we derive expected scores and the information matrix for a model used widely in radiation epidemiology, namely the linear excess relative risk (ERR) model that allows for a linear dose response (risk in relation to radiation) and distinguishes between modifiers of background rates and of the excess risk due to exposure. We show that treating the mean dose for each individual (calculated by averaging over the realizations) as if it was true dose (ignoring both shared and unshared dosimetry errors) gives asymptotically unbiased estimates (i.e. the score has expectation zero) and valid tests of the null hypothesis that the ERR slope ? is zero. Although the score is unbiased the information matrix (and hence the standard errors of the estimate of ?) is biased for ?6¼0 when ignoring errors in dose estimates, and we show how to adjust the information matrix to remove this bias, using the multiple realizations of dose. The use of these methods in the context of several studies including, the MayakWorker Cohort, and the U.S. Atomic Veterans Study, is discussed.« less

  11. Occupational dose reduction at Department of Energy contractor facilities: Bibliography of selected readings in radiation protection and ALARA; Volume 5

    SciTech Connect (OSTI)

    Dionne, B.J.; Sullivan, S.G.; Baum, J.W. [Brookhaven National Lab., Upton, NY (United States)

    1994-01-01T23:59:59.000Z

    Promoting the exchange of information related to implementation of the As Low as Reasonably Achievable (ALARA) philosophy is a continuing objective for the Department of Energy (DOE). This report was prepared by the Brookhaven National Laboratory (BNL) ALARA Center for the DOE Office of Health. It contains the fifth in a series of bibliographies on dose reduction at DOE facilities. The BNL ALARA Center was originally established in 1983 under the sponsorship of the Nuclear Regulatory Commission to monitor dose-reduction research and ALARA activities at nuclear power plants. This effort was expanded in 1988 by the DOE`s Office of Environment, Safety and Health, to include DOE nuclear facilities. This bibliography contains abstracts relating to various aspects of ALARA program implementation and dose-reduction activities, with a specific focus on DOE facilities. Abstracts included in this bibliography were selected from proceedings of technical meetings, journals, research reports, searches of the DOE Energy, Science and Technology Database (in general, the citation and abstract information is presented as obtained from this database), and reprints of published articles provided by the authors. Facility types and activities covered in the scope of this report include: radioactive waste, uranium enrichment, fuel fabrication, spent fuel storage and reprocessing, facility decommissioning, hot laboratories, tritium production, research, test and production reactors, weapons fabrication and testing, fusion, uranium and plutonium processing, radiography, and accelerators. Information on improved shielding design, decontamination, containments, robotics, source prevention and control, job planning, improved operational and design techniques, as well as on other topics, has been included. In addition, DOE/EH reports not included in previous volumes of the bibliography are in this volume (abstracts 611 to 684). This volume (Volume 5 of the series) contains 217 abstracts.

  12. Real-time Molecular Study of Bystander Effects of Low dose Low LET radiation Using Living Cell Imaging and Nanoparticale Optics

    SciTech Connect (OSTI)

    Natarajan, Mohan [UT Health Science Center at San Antonio; Xu, Nancy R [Old Dominion University; Mohan, Sumathy [UT Health Science Center at San Antonio

    2013-06-03T23:59:59.000Z

    In this study two novel approaches are proposed to investigate precisely the low dose low LET radiation damage and its effect on bystander cells in real time. First, a flow shear model system, which would provide us a near in vivo situation where endothelial cells in the presence of extra cellular matrix experiencing continuous flow shear stress, will be used. Endothelial cells on matri-gel (simulated extra cellular matrix) will be subjected to physiological flow shear (that occurs in normal blood vessels). Second, a unique tool (Single nano particle/single live cell/single molecule microscopy and spectroscopy; Figure A) will be used to track the molecular trafficking by single live cell imaging. Single molecule chemical microscopy allows one to single out and study rare events that otherwise might be lost in assembled average measurement, and monitor many target single molecules simultaneously in real-time. Multi color single novel metal nanoparticle probes allow one to prepare multicolor probes (Figure B) to monitor many single components (events) simultaneously and perform multi-complex analysis in real-time. These nano-particles resist to photo bleaching and hence serve as probes for unlimited timeframe of analysis. Single live cell microscopy allows one to image many single cells simultaneously in real-time. With the combination of these unique tools, we will be able to study under near-physiological conditions the cellular and sub-cellular responses (even subtle changes at one molecule level) to low and very low doses of low LET radiation in real time (milli-second or nano-second) at sub-10 nanometer spatial resolution. This would allow us to precisely identify, at least in part, the molecular mediators that are responsible of radiation damage in the irradiated cells and the mediators that are responsible for initiating the signaling in the neighboring cells. Endothelial cells subjected to flow shear (2 dynes/cm2 or 16 dynes/cm2) and exposed to 0.1, 1 and 10 cGy on coverslips will be examined for (a) low LET radiation-induced alterations of cellular function and its physiological relevance in real time; and (b) radiation damage triggered bystander effect on the neighboring unirradiated cells. First, to determine the low LET radiation induced alteration of cellular function we will examine: (i) the real time transformation of single membrane transporters in single living cells; (ii) the pump efficiency of membrane efflux pump of live cells in real time at the molecular level; (iii) the kinetics of single-ligand receptor interaction on single live cell surface (Figure C); and (iv) alteration in chromosome replication in living cell. Second, to study the radiation triggered bystander responses, we will examine one of the key signaling pathway i.e. TNF- alpha/NF-kappa B mediated signaling. TNF-alpha specific nano particle sensors (green) will be developed to detect the releasing dynamics, transport mechanisms and ligand-receptor binding on live cell surface in real time. A second sensor (blue) will be developed to simultaneously monitor the track of NF-kB inside the cell. The proposed nano-particle optics approach would complement our DOE funded study on biochemical mechanisms of TNF-alpha- NF-kappa B-mediated bystander effect.

  13. Prediction of human observer performance in a 2-alternative forced choice low-contrast detection task using channelized Hotelling observer: Impact of radiation dose and reconstruction algorithms

    SciTech Connect (OSTI)

    Yu Lifeng; Leng Shuai; Chen Lingyun; Kofler, James M.; McCollough, Cynthia H. [Department of Radiology, Mayo Clinic, Rochester, Minnesota 55905 (United States); Carter, Rickey E. [Division of Biomedical Statistics and Informatics, Mayo Clinic, Rochester, Minnesota 55905 (United States)

    2013-04-15T23:59:59.000Z

    Purpose: Efficient optimization of CT protocols demands a quantitative approach to predicting human observer performance on specific tasks at various scan and reconstruction settings. The goal of this work was to investigate how well a channelized Hotelling observer (CHO) can predict human observer performance on 2-alternative forced choice (2AFC) lesion-detection tasks at various dose levels and two different reconstruction algorithms: a filtered-backprojection (FBP) and an iterative reconstruction (IR) method. Methods: A 35 Multiplication-Sign 26 cm{sup 2} torso-shaped phantom filled with water was used to simulate an average-sized patient. Three rods with different diameters (small: 3 mm; medium: 5 mm; large: 9 mm) were placed in the center region of the phantom to simulate small, medium, and large lesions. The contrast relative to background was -15 HU at 120 kV. The phantom was scanned 100 times using automatic exposure control each at 60, 120, 240, 360, and 480 quality reference mAs on a 128-slice scanner. After removing the three rods, the water phantom was again scanned 100 times to provide signal-absent background images at the exact same locations. By extracting regions of interest around the three rods and on the signal-absent images, the authors generated 21 2AFC studies. Each 2AFC study had 100 trials, with each trial consisting of a signal-present image and a signal-absent image side-by-side in randomized order. In total, 2100 trials were presented to both the model and human observers. Four medical physicists acted as human observers. For the model observer, the authors used a CHO with Gabor channels, which involves six channel passbands, five orientations, and two phases, leading to a total of 60 channels. The performance predicted by the CHO was compared with that obtained by four medical physicists at each 2AFC study. Results: The human and model observers were highly correlated at each dose level for each lesion size for both FBP and IR. The Pearson's product-moment correlation coefficients were 0.986 [95% confidence interval (CI): 0.958-0.996] for FBP and 0.985 (95% CI: 0.863-0.998) for IR. Bland-Altman plots showed excellent agreement for all dose levels and lesions sizes with a mean absolute difference of 1.0%{+-} 1.1% for FBP and 2.1%{+-} 3.3% for IR. Conclusions: Human observer performance on a 2AFC lesion detection task in CT with a uniform background can be accurately predicted by a CHO model observer at different radiation dose levels and for both FBP and IR methods.

  14. Occupational dose reduction at Department of Energy contractor facilities: Bibliography of selected readings in radiation protection and ALARA

    SciTech Connect (OSTI)

    Dionne, B.J.; Sullivan, S.G.; Baum, J.W.

    1993-12-01T23:59:59.000Z

    This bibliography contains abstracts relating to various aspects of ALARA program implementation and dose reduction activities, with a focus on DOE facilities. Abstracts included in this bibliography were selected from proceedings of technical meetings, journals, research reports, searches of the DOE Energy, Science and Technology Database (in general, the citation and abstract information is presented as obtained from this database), and reprints of published articles provided by the authors. Facility types and activities covered in the scope of this report include: radioactive waste, uranium enrichment, fuel fabrication, spent fuel storage and reprocessing, facility decommissioning, hot laboratories, tritium production, research, test and production reactors, weapons fabrication and testing, fusion, uranium and plutonium processing, radiography, and aocelerators. Information on improved shielding design, decontamination, containments, robotics, source prevention and control, job planning, improved operational and design techniques, as well as on other topics, has been included. In addition, DOE/EH reports not included in previous volumes of the bibliography are in this volume (abstracts 611 to 684). This volume (Volume 5 of the series) contains 217 abstracts. An author index and a subject index are provided to facilitate use. Both indices contain the abstract numbers from previous volumes, as well as the current volume. Information that the reader feels might be included in the next volume of this bibliography should be submitted to the BNL ALARA Center.

  15. Flash polymerization of silicone oils using gamma radiation for conserving waterlogged wood

    E-Print Network [OSTI]

    Gidden, Richmond Paul

    1996-01-01T23:59:59.000Z

    the SFD-I /SFD-5 mix. These bulked samples were exposed to gamma radiation emitted from a nuclear research reactor and received gamma doses ranging from 30 Gy to 228 Gy with dose rates ranging from 0.6 Gy/min to 5.1 Gy/min. Following irradiation, thin...

  16. Dose optimization with first-order total-variation minimization for dense angularly sampled and sparse intensity modulated radiation therapy (DASSIM-RT)

    SciTech Connect (OSTI)

    Kim, Hojin; Li Ruijiang; Lee, Rena; Goldstein, Thomas; Boyd, Stephen; Candes, Emmanuel; Xing Lei [Department of Electrical Engineering, Stanford University, Stanford, California 94305-9505 (United States) and Department of Radiation Oncology, Stanford University, Stanford, California 94305-5847 (United States); Department of Radiation Oncology, Stanford University, Stanford, California 94305-5847 (United States); Department of Radiation Oncology, Ehwa University, Seoul 158-710 (Korea, Republic of); Department of Electrical Engineering, Stanford University, Stanford, California 94305-9505 (United States); Department of Statistics, Stanford University, Stanford, California 94305-4065 (United States); Department of Radiation Oncology, Stanford University, Stanford, California 94305-5304 (United States)

    2012-07-15T23:59:59.000Z

    Purpose: A new treatment scheme coined as dense angularly sampled and sparse intensity modulated radiation therapy (DASSIM-RT) has recently been proposed to bridge the gap between IMRT and VMAT. By increasing the angular sampling of radiation beams while eliminating dispensable segments of the incident fields, DASSIM-RT is capable of providing improved conformity in dose distributions while maintaining high delivery efficiency. The fact that DASSIM-RT utilizes a large number of incident beams represents a major computational challenge for the clinical applications of this powerful treatment scheme. The purpose of this work is to provide a practical solution to the DASSIM-RT inverse planning problem. Methods: The inverse planning problem is formulated as a fluence-map optimization problem with total-variation (TV) minimization. A newly released L1-solver, template for first-order conic solver (TFOCS), was adopted in this work. TFOCS achieves faster convergence with less memory usage as compared with conventional quadratic programming (QP) for the TV form through the effective use of conic forms, dual-variable updates, and optimal first-order approaches. As such, it is tailored to specifically address the computational challenges of large-scale optimization in DASSIM-RT inverse planning. Two clinical cases (a prostate and a head and neck case) are used to evaluate the effectiveness and efficiency of the proposed planning technique. DASSIM-RT plans with 15 and 30 beams are compared with conventional IMRT plans with 7 beams in terms of plan quality and delivery efficiency, which are quantified by conformation number (CN), the total number of segments and modulation index, respectively. For optimization efficiency, the QP-based approach was compared with the proposed algorithm for the DASSIM-RT plans with 15 beams for both cases. Results: Plan quality improves with an increasing number of incident beams, while the total number of segments is maintained to be about the same in both cases. For the prostate patient, the conformation number to the target was 0.7509, 0.7565, and 0.7611 with 80 segments for IMRT with 7 beams, and DASSIM-RT with 15 and 30 beams, respectively. For the head and neck (HN) patient with a complicated target shape, conformation numbers of the three treatment plans were 0.7554, 0.7758, and 0.7819 with 75 segments for all beam configurations. With respect to the dose sparing to the critical structures, the organs such as the femoral heads in the prostate case and the brainstem and spinal cord in the HN case were better protected with DASSIM-RT. For both cases, the delivery efficiency has been greatly improved as the beam angular sampling increases with the similar or better conformal dose distribution. Compared with conventional quadratic programming approaches, first-order TFOCS-based optimization achieves far faster convergence and smaller memory requirements in DASSIM-RT. Conclusions: The new optimization algorithm TFOCS provides a practical and timely solution to the DASSIM-RT or other inverse planning problem requiring large memory space. The new treatment scheme is shown to outperform conventional IMRT in terms of dose conformity to both the targetand the critical structures, while maintaining high delivery efficiency.

  17. Technical Note: Influence of the phantom material on the absorbed-dose energy dependence of the EBT3 radiochromic film for photons in the energy range 3 keV–18 MeV

    SciTech Connect (OSTI)

    Hermida-López, M., E-mail: mhermida@vhebron.net [NCTeam, Strahlenklinik, Universitätsklinikum Essen, Hufelandstraße 55, Essen D-45122, Germany and Servei de Física i Protecció Radiològica, Hospital Universitari Vall d’Hebron, Pg. Vall d’Hebron 119-129, Barcelona 08035 (Spain); Lüdemann, L.; Flühs, A. [Medical Physics, Strahlenklinik, Universitätsklinikum Essen, Hufelandstraße 55, Essen D-45122 (Germany); Brualla, L. [NCTeam, Strahlenklinik, Universitätsklinikum Essen, Hufelandstraße 55, Essen D-45122 (Germany)

    2014-11-01T23:59:59.000Z

    Purpose: Water is the reference medium for radiation therapy dosimetry, but for film dosimetry it is more practical to use a solid phantom. As the composition of solid phantoms differs from that of water, the energy dependence of film exposed within solid phantoms may also differ. The energy dependence of a radiochromic film for a given beam quality Q (energy for monoenergetic beams) has two components: the intrinsic energy dependence and the absorbed-dose energy dependence f(Q), the latter of which can be calculated through a Monte Carlo simulation of radiation transport. The authors used Monte Carlo simulations to study the influence of the phantom material on the f(Q) of the EBT3 radiochromic film (Ashland Specialty Ingredients, Wayne, NJ) for photon beams with energies between 3 keV and 18 MeV. Methods: All simulations were carried out with the general-purpose Monte Carlo code PENELOPE 2011. The geometrical model consisted of a cylindrical phantom, with the film positioned at different depths depending on the initial photon energy. The authors simulated monoenergetic parallel photon beams and x-ray beams from a superficial therapy system. To validate their choice of simulation parameters, they also calculated f(Q) for older film models, EBT and EBT2, comparing with published results. In addition to water, they calculated f(Q) of the EBT3 film for solid phantom materials commonly used for film dosimetry: RW1 and RW3 (PTW-Freiburg, Freiburg, Germany), Solid Water (Gammex-RMI, Madison, WI), and PMMA. Finally, they combined their calculated f(Q) with published overall energy response data to obtain the intrinsic energy dependence of the EBT3 film in water. Results: The calculated f(Q) for EBT and EBT2 films was statistically compatible with previously published data. Between 10 keV and 18 MeV, the variation found in f(Q) of the EBT3 film for water was within 2.3%, with a standard statistical uncertainty less than 1%. If the quantity dose-to-water in the phantom is considered, which is the common practice in radiation dosimetry, the maximum difference of energy dependence for the solid phantoms with respect to water is about 6%, at an energy of 50 keV. Conclusions: The EBT3 film shows a reasonably constant absorbed-dose energy dependence when irradiated in water. If the dose-to-water in the phantom is considered, the maximum difference of EBT3 film energy dependence with the solid phantoms studied with respect to water is about 6% (at an energy of 50 keV). The reported overall energy dependence of the EBT3 film in water at energies below 100 keV is mainly due to the intrinsic energy dependence.

  18. Age and Comorbid Illness Are Associated With Late Rectal Toxicity Following Dose-Escalated Radiation Therapy for Prostate Cancer

    SciTech Connect (OSTI)

    Hamstra, Daniel A. [Department of Radiation Oncology, University of Michigan Medical Center, Ann Arbor, Michigan (United States)] [Department of Radiation Oncology, University of Michigan Medical Center, Ann Arbor, Michigan (United States); Stenmark, Matt H.; Ritter, Tim [Department of Radiation Oncology, University of Michigan Medical Center, Ann Arbor, Michigan (United States) [Department of Radiation Oncology, University of Michigan Medical Center, Ann Arbor, Michigan (United States); Department of Radiation Oncology, Veterans Affairs Medical Center, Ann Arbor, Michigan (United States); Litzenberg, Dale; Jackson, William; Johnson, Skyler; Albrecht-Unger, Liesel; Donaghy, Alex; Phelps, Laura; Blas, Kevin; Halverson, Schuyler; Marsh, Robin; Olson, Karin [Department of Radiation Oncology, University of Michigan Medical Center, Ann Arbor, Michigan (United States)] [Department of Radiation Oncology, University of Michigan Medical Center, Ann Arbor, Michigan (United States); Feng, Felix Y., E-mail: ffeng@med.umich.edu [Department of Radiation Oncology, University of Michigan Medical Center, Ann Arbor, Michigan (United States)

    2013-04-01T23:59:59.000Z

    Purpose: To assess the impacts of patient age and comorbid illness on rectal toxicity following external beam radiation therapy (EBRT) for prostate cancer and to assess the Qualitative Analysis of Normal Tissue Effects in the Clinic (QUANTEC) normal tissue complication probability (NTCP) model in this context. Methods and Materials: Rectal toxicity was analyzed in 718 men previously treated for prostate cancer with EBRT (?75 Gy). Comorbid illness was scored using the Charlson Comorbidity Index (CCMI), and the NTCP was evaluated with the QUANTEC model. The influence of clinical and treatment-related parameters on rectal toxicity was assessed by Kaplan-Meier and Cox proportional hazards models. Results: The cumulative incidence of rectal toxicity grade ?2 was 9.5% and 11.6% at 3 and 5 years and 3.3% and 3.9% at 3 and 5 years for grade ?3 toxicity, respectively. Each year of age predicted an increasing relative risk of grade ?2 (P<.03; hazard ratio [HR], 1.04 [95% confidence interval (CI), 1.01-1.06]) and ?3 rectal toxicity (P<.0001; HR, 1.14 [95% CI,1.07-1.22]). Increasing CCMI predicted rectal toxicity where a history of either myocardial infarction (MI) (P<.0001; HR, 5.1 [95% CI, 1.9-13.7]) or congestive heart failure (CHF) (P<.0006; HR, 5.4 [95% CI, 0.6-47.5]) predicted grade ?3 rectal toxicity, with lesser correlation with grade ?2 toxicity (P<.02 for MI, and P<.09 for CHF). An age comorbidity model to predict rectal toxicity was developed and confirmed in a validation cohort. The use of anticoagulants increased toxicity independent of age and comorbidity. NTCP was prognostic for grade ?3 (P=.015) but not grade ?2 (P=.49) toxicity. On multivariate analysis, age, MI, CHF, and an NTCP >20% all correlated with late rectal toxicity. Conclusions: Patient age and a history of MI or CHF significantly impact rectal toxicity following EBRT for the treatment of prostate cancer, even after controlling for NTCP.

  19. Hanford Environmental Dose Reconstruction Project

    SciTech Connect (OSTI)

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

    1991-01-01T23:59:59.000Z

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

  20. Analysis of radiation doses from operation of postulated commercial spent fuel transportation systems: Analysis of a system containing a monitored retrievable storage facility. Addendum 1

    SciTech Connect (OSTI)

    Smith, R.I.; Daling, P.M. [Pacific Northwest Lab., Richland, WA (United States); Faletti, D.W. [Westinghouse Hanford Co., Richland, WA (United States)

    1992-04-01T23:59:59.000Z

    This addendum report extends the original study of the estimated radiation doses to the public and to workers resulting from transporting spent nuclear fuel from commercial nuclear power reactor stations through the federal waste management system (FWMS), to a system that contains a monitored retrievable storage (MRS) facility. The system concepts and designs utilized herein are consistent with those used in the original study (circa 1985--1987). Because the FWMS design is still evolving, the results of these analyses may no longer apply to the design for casks and cask handling systems that are currently being considered. Four system scenarios are examined and compared with the reference No-MRS scenario (all spent fuel transported directly from the reactors to the western repository in standard-capacity truck and rail casks). In Scenarios 1 and 2, an MRS facility is located in eastern United States and ships either intact fuel assemblies or consolidated fuel rods and compacted assembly hardware in canisters. In Scenarios 3 and 4, an MRS facility is located in the western United States and ship either intact fuel assemblies or consolidated fuel rods and compacted assembly hardware in canisters.

  1. Modelling of long-range transport of Southeast Asia biomass-burning aerosols to Taiwan and their radiative forcings over East Asia

    SciTech Connect (OSTI)

    Lin, Chuan-Yao; Zhao, Chun; Liu, Xiaohong; Lin, Neng-Huei; Chen, Wei-Nei

    2014-10-12T23:59:59.000Z

    Biomass burning is a major source of aerosols and air pollutants during the springtime in Southeast Asia. At Lulin mountain background station (elevation 2862 m) in Taiwan, the concentrations of carbon monoxide (CO), ozone (O3) and particulate matter particles with diameter less than 10 ?m (PM10), were measured around 150-250 ppb, 40-60 ppb, and 10-30?g/m3, respectively at spring time (February-April) during 2006 and 2009, which are about 2~3 times higher than those in other seasons. Observations and simulation results indicate that the higher concentrations during the spring time are clearly related to biomass burning plumes transported from the Indochina Peninsula of Southeast Asia. The spatial distribution of high aerosols optical depth (AOD) were identified by the satellite measurement and Aerosol Robotic Network (AERONET) ground observation, and could be reasonably captured by the WRF-Chem model during the study period of 15-18 March, 2008. AOD reached as high as 0.8-1.0 in Indochina ranging from 10 to 22°N and 95 to 107°E. Organic carbon (OC) is a major contributor of AOD over Indochina according to simulation results. The contributor of AOD from black carbon (BC) is minor when compared with OC over the Indochina. However, the direct absorption radiative forcing of BC in the atmosphere could reach 35-50 W m-2, which is about 8-10 times higher than that of OC. The belt shape of radiation reduction at surface from Indochina to Taiwan could be as high 20-40 W m-2 during the study period. The implication of the radiative forcing from biomass burning aerosols and their impact on the regional climate in East Asia is our major concern.

  2. Prediction of proton and neutron absorbed-dose distributions in proton beam radiation therapy using Monte Carlo n-particle transport code (MCNPX)

    E-Print Network [OSTI]

    Massingill, Brian Edward

    2009-05-15T23:59:59.000Z

    The objective of this research was to develop a complex MCNPX model of the human head to predict absorbed dose distributions during proton therapy of ocular tumors. Absorbed dose distributions using the complex geometry were compared to a simple...

  3. Prediction of proton and neutron absorbed-dose distributions in proton beam radiation therapy using Monte Carlo n-particle transport code (MCNPX) 

    E-Print Network [OSTI]

    Massingill, Brian Edward

    2009-05-15T23:59:59.000Z

    The objective of this research was to develop a complex MCNPX model of the human head to predict absorbed dose distributions during proton therapy of ocular tumors. Absorbed dose distributions using the complex geometry were compared to a simple...

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

    SciTech Connect (OSTI)

    Khor, Richard [Division of Radiation Oncology and Cancer Imaging, Peter MacCallum Cancer Centre, and University of Melbourne, Melbourne (Australia)] [Division of Radiation Oncology and Cancer Imaging, Peter MacCallum Cancer Centre, and University of Melbourne, Melbourne (Australia); Duchesne, Gillian [Division of Radiation Oncology and Cancer Imaging, Peter MacCallum Cancer Centre, and University of Melbourne, Melbourne (Australia) [Division of Radiation Oncology and Cancer Imaging, Peter MacCallum Cancer Centre, and University of Melbourne, Melbourne (Australia); Monash University, Melbourne (Australia); Tai, Keen-Hun; Foroudi, Farshad; Chander, Sarat; Van Dyk, Sylvia; Garth, Margaret [Division of Radiation Oncology and Cancer Imaging, Peter MacCallum Cancer Centre, and University of Melbourne, Melbourne (Australia)] [Division of Radiation Oncology and Cancer Imaging, Peter MacCallum Cancer Centre, and University of Melbourne, Melbourne (Australia); Williams, Scott, E-mail: Scott.Williams@petermac.org [Division of Radiation Oncology and Cancer Imaging, Peter MacCallum Cancer Centre, and University of Melbourne, Melbourne (Australia)] [Division of Radiation Oncology and Cancer Imaging, Peter MacCallum Cancer Centre, and University of Melbourne, Melbourne (Australia)

    2013-03-01T23:59:59.000Z

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

  5. Gleason Pattern 5 Is the Greatest Risk Factor for Clinical Failure and Death From Prostate Cancer After Dose-Escalated Radiation Therapy and Hormonal Ablation

    SciTech Connect (OSTI)

    Sabolch, Aaron [University of Michigan Medical School, Ann Arbor, MI (United States); Feng, Felix Y. [University of Michigan Medical School, Ann Arbor, MI (United States); Department of Radiation Oncology, Ann Arbor, MI (United States); Veterans Administration Medical Center, Ann Arbor, MI (United States); Daignault-Newton, Stephanie [University of Michigan Medical School, Ann Arbor, MI (United States); Division of Biostatistics, Ann Arbor, MI (United States); Halverson, Schuyler; Blas, Kevin; Phelps, Laura [University of Michigan Medical School, Ann Arbor, MI (United States); Olson, Karin B. [University of Michigan Medical School, Ann Arbor, MI (United States); Department of Radiation Oncology, Ann Arbor, MI (United States); Sandler, Howard M. [Department of Radiation Oncology, Cedars Sinai Medical Center, Los Angeles, CA (United States); Hamstra, Daniel A., E-mail: dhamm@med.umich.edu [Department of Radiation Oncology, Ann Arbor, MI (United States)

    2011-11-15T23:59:59.000Z

    Purpose: The division of Gleason score (GS) into three categories (2-6, 7, 8-10) may not fully use its prognostic power, as revealed by recent reports demonstrating the presence of Gleason Pattern 5 (GP5) as a strong predictor for biochemical recurrence. Therefore, we analyzed the clinical outcomes in patients treated with dose-escalated radiation therapy (RT) based on the presence or absence of GP5. Methods and Materials: Outcomes were analyzed for 718 men treated for localized prostate cancer with external-beam RT to a minimum planning target volume dose of at least 75 Gy. We assessed the impact of GP5 and that of pretreatment- and treatment-related factors on freedom from biochemical failure, freedom from metastasis (FFM), cause-specific survival (CSS), and overall survival (OS). Results: At biopsy, 89% of patients had no GP5, and 11% (76/718) had GP5. There were no differences in age, comorbid illness, T stage, prostate-specific antigen, or the use or duration of androgen deprivation therapy between GS8 without GP5 and GS8-10 with GP5. The presence of GP5 predicted lower FFM (p < 0.002; hazard ratio [HR] 3.4 [1.7-7.1]); CSS (p < 0.0001; HR 12.9 [5.4-31]); and OS (p < 0.0001; HR 3.6 [2.0-6.5]) in comparison with GS8 (without GP5). The 8-year FFM, CSS, and OS were 89%, 98%, and 57%, respectively, for those with Gleason 8 prostate cancer without GP5 in comparison with 61%, 55%, and 31%, respectively, for those with GP5. In addition, both FFM and CSS were strongly influenced by androgen deprivation therapy given concurrently with RT. On multivariate analysis, GP5 was the strongest prognostic factor for all clinical endpoints, including OS. Conclusion: The presence of GP5 predicts for worse clinical behavior, which therefore needs to be accounted for by risk stratification schemes. Further intensification of local and/or systemic therapy may be appropriate for such patients.

  6. Nuclear apoJ: A low dose radiation inducible regulator of cell death. Final report for period September 15, 1998 - September 14, 2001

    SciTech Connect (OSTI)

    Aronow, Bruce J.

    2002-04-19T23:59:59.000Z

    This project was based on preliminary data that was published by Dr. Boothman (Yang et al. 2000) which indicated a strong induction of apoJ gene expression, increased secretion of the protein, and accumulation of an apparently somewhat different form of the apoJ protein in the nucleus of MCF-7 breast carcinoma cells undergoing response to DNA damage. A clone expressing apoJ protein was isolated that was capable of interacting with Ku80, a component of the double strand break repair complex that is essential for the successful repair of rearranging immunoglobulin and T-cell receptor genes as evidenced by failure to produce mature B and T cells in the absence of Ku70. ApoJ clones isolated and characterized by Dr. Boothman bound strongly to a Ku-70 ''bait'' protein. Over-expression of these same clones in a cell line was capable of killing the cell. ApoJ is very strongly induced in many instances of programmed cell death and has been proposed repeatedly to play some sort of effector role in the process. Our principle hypothesis for this study was that the strong induction of the apoJ gene and the particular expression of a nuclear form of the protein was potentially a causal factor in the decision point made by the cell as it attempts to repair double-strand breakage based DNA damage. The hypothesis was that if sufficiently high damage occurred, it would be deleterious to maintain the cell's viability through continued DNA repair. One method to inhibit DNA repair might be by inhibiting proteins such as Ku-70 that are necessary for double-strand break repair. If apoJ does play a critical role in tipping the decision balance over to cell death, we reasoned that deficiency of apoJ would cause increased accumulation of cells with DNA damage and that this might decrease cell death in response to DNA damage and increase tumor occurrence rates. To test this hypothesis and its potential implications, we exposed wildtype and apoJ deficient animals that we constructed through gene targeting to increasing levels of ionizing radiation from a Cesium source. Data gathered under the support of this grant application initially indicated that apoJ deficient animals were more resistant to radiation, but as we accumulated more and more data points and covered a tighter exposure range, the genotype-based differences became insignificant. However, the possibility existed that because mortality based radiation-resistance could be attributable to mechanism for which nuclear apoJ was not rate determining, we maintained a very large of colony of apoJ knockout and wildtype animals in both the C57/B16 and Cv129 strain backgrounds that were exposed to sub-lethal levels of ionizing radiation to monitor for the occurrence of tumors. These animals were allowed to fully recover and age normally in either germ free or normal animal housing. Our results demonstrated no significant differences between wildtype and apoJ knockout animals over a period that extended up to 30 months for individual animals. We recorded similar weight gain, a relatively low mortality rate, and a similar mixture and rate of sarcoma and adenocarcinomas after surviving the initial ionizing radiation exposures. Thus we conclude that apoJ gene function, which was totally eliminated by our gene targeting, did not influence radiation sensitivity or serve as a tumor suppressor in response to DNA damage.

  7. High-Dose Hypofractionated Proton Beam Radiation Therapy Is Safe and Effective for Central and Peripheral Early-Stage Non-Small Cell Lung Cancer: Results of a 12-Year Experience at Loma Linda University Medical Center

    SciTech Connect (OSTI)

    Bush, David A., E-mail: dbush@llu.edu [Department of Radiation Oncology, Loma Linda University Medical Center, Loma Linda, California (United States); Cheek, Gregory [Department of Pulmonary Medicine, Loma Linda University Medical Center, Loma Linda, California (United States); Zaheer, Salman; Wallen, Jason [Department of Thoracic Surgery, Loma Linda University Medical Center, Loma Linda, California (United States); Mirshahidi, Hamid [Department of Medical Oncology, Loma Linda University Medical Center, Loma Linda, California (United States); Katerelos, Ari; Grove, Roger; Slater, Jerry D. [Department of Radiation Oncology, Loma Linda University Medical Center, Loma Linda, California (United States)

    2013-08-01T23:59:59.000Z

    Purpose: We update our previous reports on the use of hypofractionated proton beam radiation therapy for early-stage lung cancer patients. Methods and Materials: Eligible subjects had biopsy-proven non-small cell carcinoma of the lung and were medically inoperable or refused surgery. Clinical workup required staging of T1 or T2, N0, M0. Subjects received hypofractionated proton beam therapy to the primary tumor only. The dose delivered was sequentially escalated from 51 to 60 Gy, then to 70 Gy in 10 fractions over 2 weeks. Endpoints included toxicity, pulmonary function, overall survival (OS), disease-specific survival (DSS), and local control (LC). Results: One hundred eleven subjects were analyzed for treatment outcomes. The patient population had the following average characteristics; age 73.2 years, tumor size 3.6 cm, and 1.33 L forced expiratory volume in 1 second. The entire group showed improved OS with increasing dose level (51, 60, and 70 Gy) with a 4-year OS of 18%, 32%, and 51%, respectively (P=.006). Peripheral T1 tumors exhibited LC of 96%, DSS of 88%, and OS of 60% at 4 years. Patients with T2 tumors showed a trend toward improved LC and survival with the 70-Gy dose level. On multivariate analysis, larger tumor size was strongly associated with increased local recurrence and decreased survival. Central versus peripheral location did not correlate with any outcome measures. Clinical radiation pneumonitis was not found to be a significant complication, and no patient required steroid therapy after treatment for radiation pneumonitis. Pulmonary function was well maintained 1 year after treatment. Conclusions: High-dose hypofractionated proton therapy achieves excellent outcomes for lung carcinomas that are peripherally or centrally located. The 70-Gy regimen has been adopted as standard therapy for T1 tumors at our institution. Larger T2 tumors show a trend toward improved outcomes with higher doses, suggesting that better results could be seen with intensified treatment.

  8. Dose Reduction Techniques

    SciTech Connect (OSTI)

    WAGGONER, L.O.

    2000-05-16T23:59:59.000Z

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

  9. Biological doses with template distribution patterns

    SciTech Connect (OSTI)

    Harrop, R. (Simon Fraer Univ., Burnaby, British Columbia); Haymond, H.R.; Nisar, A.; Syed, A.N.M.; Feder, B.H.; Neblett, D.L.

    1981-02-01T23:59:59.000Z

    Consideration of radiation dose rate effects emphasizes advantages of the template method for lateral distribution of multiple sources in treatment of laterally infiltrating gynecologic cancer, when compared to a conventional technique with colpostats. Biological doses in time dose fractionation (TDF), ret and reu units are calculated for the two treatment methods. With the template method the lateral dose (point B) is raised without significantly increasing the doses to the rectum and bladder, that is, relatively, the calculated biological doses at point A and B are more nearly equivalent and the doses to the rectum and bladder are significantly lower than the dose to point B.

  10. Radiation hardness of the storage phosphor europium doped potassium chloride for radiation therapy dosimetry

    SciTech Connect (OSTI)

    Driewer, Joseph P.; Chen, Haijian; Osvet, Andres; Low, Daniel A.; Li, H. Harold [Department of Radiation Oncology, Washington University School of Medicine, 4921 Parkview Place, Campus Box 8224, St. Louis, Missouri 63110 and Nuclear Science and Engineering Institute, University of Missouri, E4431 Lafferre Hall, Columbia, Missouri 65211 (United States); Department of Radiation Oncology, Washington University School of Medicine, 4921 Parkview Place, Campus Box 8224, St. Louis, Missouri 63110 (United States); Department of Materials Science and Engineering, Friedrich-Alexander-University Erlangen-Nuremberg, Martensstrasse 7, Erlangen 91058 (Germany); Department of Radiation Oncology, Washington University School of Medicine, 4921 Parkview Place, Campus Box 8224, St. Louis, Missouri 63110 (United States)

    2011-08-15T23:59:59.000Z

    Purpose: An important property of a reusable dosimeter is its radiation hardness, that is, its ability to retain its dosimetric merits after irradiation. The radiation hardness of europium doped potassium chloride (KCl:Eu{sup 2+}), a storage phosphor material recently proposed for radiation therapy dosimetry, is examined in this study. Methods: Pellet-style KCl:Eu{sup 2+} dosimeters, 6 mm in diameter, and 1 mm thick, were fabricated in-house for this study. The pellets were exposed by a 6 MV photon beam or in a high dose rate {sup 137}Cs irradiator. Macroscopic properties, such as radiation sensitivity, dose response linearity, and signal stability, were studied with a laboratory photostimulated luminescence (PSL) readout system. Since phosphor performance is related to the state of the storage centers and the activator, Eu{sup 2+}, in the host lattice, spectroscopic and temporal measurements were carried out in order to explore radiation-induced changes at the microscopic level. Results: KCl:Eu{sup 2+} dosimeters retained approximately 90% of their initial signal strength after a 5000 Gy dose history. Dose response was initially supralinear over the dose range of 100-700 cGy but became linear after 60 Gy. Linearity did not change significantly in the 0-5000 Gy dose history spanned in this study. Annealing high dose history chips resulted in a return of supralinearity and a recovery of sensitivity. There were no significant changes in the PSL stimulation spectra, PSL emission spectra, photoluminescence spectra, or luminescence lifetime, indicating that the PSL signal process remains intact after irradiation but at a reduced efficiency due to reparable radiation-induced perturbations in the crystal lattice. Conclusions: Systematic studies of KCl:Eu{sup 2+} material are important for understanding how the material can be optimized for radiation therapy dosimetry purposes. The data presented here indicate that KCl:Eu{sup 2+} exhibits strong radiation hardness and lends support for further investigations of this novel material.

  11. An evaluation of the TSE MR sequence for time efficient data acquisition in polymer gel dosimetry of applications involving high doses and steep dose gradients

    SciTech Connect (OSTI)

    Baras, P.; Seimenis, I.; Sandilos, P.; Vlahos, L.; Bieganski, T.; Georgiou, E.; Pantelis, E.; Papagiannis, P.; Sakelliou, L. [Philips Hellas Medical Systems, 44 Kifissias Ave., Maroussi 151 25, Athens (Greece); Department of Radiology, Medical School, University of Athens, Areteion Hospital, 76 Vas. Sofias Ave., 115 28 Athens (Greece) and Medical Physics Department, Hygeia Hospital, Kiffisias Avenue, 24 Erythrou Stavrou, Marousi, 151 23, Athens (Greece); Department of Radiology, Mother's Memorial Hospital, Rzgowska 281/289, 93-388, Lodz (Poland); Medical Physics Department, University of Athens, 75 Mikras Asias, 115 27 Athens (Greece); Nuclear and Particle Physics Section, Physics Department, University of Athens, Panepistimioupolis, Ilisia, 157 71 Athens (Greece)

    2005-11-15T23:59:59.000Z

    The use of magnetic resonance imaging as a readout method for polymer gel dosimetry commonly involves long imaging sessions, particularly when high spatial resolution is required in all three dimensions, for the investigation of dose distributions with steep dose gradients and stringent dose delivery specifications. In this work, a volume selective turbo spin echo (TSE) pulse sequence is compared to the established Carr-Purcell-Meiboom-Gill (CPMG) multiecho acquisition with regard to providing accurate dosimetric results in significantly reduced imaging times. Polyethylene glycol diacrylate based (PABIG) gels were irradiated and subsequently scanned to obtain R2 relaxation rate measurements, using a CPMG multiecho sequence and a dual echo TSE utilizing an acceleration (turbo) factor of 64. R2 values, plotted against corresponding Monte Carlo dose calculations, provided calibration data of PABIG gels dose response over a wide dose range. A linear R2 versus dose relationship was demonstrated for both sequences with TSE results presenting reduced dose sensitivity. Although TSE data were found to deviate from linearity at lower doses compared to CPMG data, a relatively wide dynamic dose range of response extending up to approximately 100 Gy was observed for both sequences. The TSE and CPMG sequences were evaluated with a brachytherapy irradiation using a high dose rate {sup 192}Ir source and a gamma knife stereotactic radiosurgery irradiation with a single 4 mm collimator helmet shot. Dosimetric results obtained with the TSE and CPMG are shown to compare equally well with the expected dose distributions for these irradiations. The 60-fold scan time reduction achieved with TSE implies that this sequence could prove to be a useful tool for the introduction of polymer gel dosimetry in clinical radiation therapy applications involving high doses and steep dose gradients.

  12. Relevance of biotic pathways to the long-term regulation of nuclear waste disposal. Estimation of radiation dose to man resulting from biotic transport: the BIOPORT/MAXI1 software package. Volume 5

    SciTech Connect (OSTI)

    McKenzie, D.H.; Cadwell, L.L.; Gano, K.A.; Kennedy, W.E. Jr.; Napier, B.A.; Peloquin, R.A.; Prohammer, L.A.; Simmons, M.A.

    1985-10-01T23:59:59.000Z

    BIOPORT/MAXI1 is a collection of five computer codes designed to estimate the potential magnitude of the radiation dose to man resulting from biotic transport processes. Dose to man is calculated for ingestion of agricultural crops grown in contaminated soil, inhalation of resuspended radionuclides, and direct exposure to penetrating radiation resulting from the radionuclide concentrations established in the available soil surface by the biotic transport model. This document is designed as both an instructional and reference document for the BIOPORT/MAXI1 computer software package and has been written for two major audiences. The first audience includes persons concerned with the mathematical models of biological transport of commercial low-level radioactive wastes and the computer algorithms used to implement those models. The second audience includes persons concerned with exercising the computer program and exposure scenarios to obtain results for specific applications. The report contains sections describing the mathematical models, user operation of the computer programs, and program structure. Input and output for five sample problems are included. In addition, listings of the computer programs, data libraries, and dose conversion factors are provided in appendices.

  13. Risk of Radiation Retinopathy in Patients With Orbital and Ocular Lymphoma

    SciTech Connect (OSTI)

    Kaushik, Megha; Pulido, Jose S. [Department of Ophthalmology, Mayo Clinic, Rochester, Minnesota (United States)] [Department of Ophthalmology, Mayo Clinic, Rochester, Minnesota (United States); Schild, Steven E. [Division of Radiation Oncology, Mayo Clinic, Scottsdale, Arizona (United States)] [Division of Radiation Oncology, Mayo Clinic, Scottsdale, Arizona (United States); Stafford, Scott, E-mail: stafford.scott@mayo.edu [Division of Radiation Oncology, Mayo Clinic, Rochester, Minnesota (United States)] [Division of Radiation Oncology, Mayo Clinic, Rochester, Minnesota (United States)

    2012-12-01T23:59:59.000Z

    Purpose: Radiation retinopathy is a potential long-term complication of radiation therapy to the orbit. The risk of developing this adverse effect is dose dependent; however, the threshold is unclear. The aim of this study was to identify the risk of developing radiation retinopathy at increasing radiation doses. Methods and Materials: A 40-year retrospective review was performed of patients who received external beam radiation therapy for ocular/orbital non-Hodgkin lymphoma (NHL). Results: Sixty-seven patients who had at least one ophthalmic follow-up examination were included in this study. Most patients (52%) were diagnosed with NHL involving the orbit. Patients received external beam radiation therapy at doses between 1886 and 5400 cGy (mean, 3033 {+-} 782 cGy). Radiation retinopathy developed in 12% of patients, and the median time to diagnosis was 27 months (range, 15-241months). The mean prescribed radiation dose in patients with retinopathy was 3309 {+-} 585 cGy, and the estimated retinal dose (derived by reviewing the dosimetry) was 3087 {+-} 1030 cGy. The incidence of retinopathy increased with dose. The average prescribed daily fractionated dose was higher in patients who developed retinopathy than in patients who did not (mean, 202 cGy vs 180 cGy, respectively; P = .04). More patients with radiation retinopathy had comorbid diabetes mellitus type 2 than patients without retinopathy (P = .015). In our study, the mean visual acuity of the eyes that received radiation was worse than that of the eyes that did not (P = .027). Other postradiotherapy ocular findings included keratitis (6%), dry eyes (39%), and cataract (33%). Conclusions: Radiation retinopathy, a known complication of radiotherapy for orbital tumors, relates to vascular comorbidities and dose. Higher total doses and larger daily fractions (>180 cGy) appear to be related to higher rates of retinopathy. Future larger studies are required to identify a statistically significant threshold for the development of retinopathy.

  14. The change of radiation doses to the patient when switching from conventional technique to digital technique without films in barium enema and IVU examinations. Final report SSI research project P933

    E-Print Network [OSTI]

    Sjöholm, B

    2003-01-01T23:59:59.000Z

    X-ray examinations of the colon (barium enema) and the kidneys (IVU) are combined with rather high radiation doses to the patients when using analogue technique with film-screen systems. It is therefore of great interest to see if the change from analogue to digital technique involves a reduction of doses. Barium enema and IVU examinations were monitored with DAP-meters before and after the X-ray department changed to digital techniques. For IVU also the change from storage phosphor plates to a Direct Digital detector is included. The study comprises between 53 and 87 patients for each modality of the two examinations. A considerable dose reduction was observed. In barium enema the overview images with large field sizes were omitted when using digital technique. On the other hand the number of spot images was increased from 6 to 22. The fluoroscopy time was increased from 4 minutes to 6 minutes. The DAP value was reduced from 54,3 Gy cm sup 2 to 21,9 Gy cm sup 2. For IVU a dose reduction from 44,5 Gy cm sup 2...

  15. Hanford Environmental Dose Reconstruction Project

    SciTech Connect (OSTI)

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

    1992-06-01T23:59:59.000Z

    The objective of the Hanford Environmental Dose Reconstruction Project is to estimate the radiation doses that individuals and populations could have received from nuclear operations at Hanford since 1944. The project is being managed and conducted by the Battelle Pacific Northwest Laboratories under contract with the Centers for Disease Control. The independent Technical Steering Panel (TSP) provides technical direction. The project is divided into the following technical tasks. These tasks correspond to the path radionuclides followed, from release to impact on humans (dose estimates): source terms; environmental transport; environmental monitoring data; demography, food consumption, and agriculture; environmental pathways and dose estimates.

  16. Investigation of radiation patterns in the 8-12 micron range as observed by Tiros III over the Caribbean Sea during the period 20-21 July 1961

    E-Print Network [OSTI]

    Mohler, Paul Irvin

    1963-01-01T23:59:59.000Z

    low pressure area in the general vicinity of Panama and western Columbia. It is also known from a study by Cramer (1963) that an upper-level trough existed from Costa Rica to Jamaica. The main features shown by Figure 2 are the very close... relationship between the radiation cold center and the heavy cloud cover around the Panama area and the warm radiation tongue and absence of clouds in the central Caribbean Sea. There also appeared to be a very good re- lationship between the warm radiation...

  17. Integer Programs for High Dose Rate Brachytherapy Needle and Dose Planning that Directly Optimize Clinical Objectives

    E-Print Network [OSTI]

    Siauw, Ko-Ay Timmy

    2012-01-01T23:59:59.000Z

    radiation received by the bulb of the penis correlates withof radiation dose to the bulb of the penis in men with andavoided puncturing the penile bulb; the average number of

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

    SciTech Connect (OSTI)

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

    2012-03-01T23:59:59.000Z

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

  19. A Reanalysis of Curvature in the Dose Response for Cancer and Modifications by Age at Exposure Following Radiation Therapy for Benign Disease

    SciTech Connect (OSTI)

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

    2013-02-01T23:59:59.000Z

    Purpose: To assess the shape of the dose response for various cancer endpoints and modifiers by age and time. Methods and Materials: Reanalysis of the US peptic ulcer data testing for heterogeneity of radiogenic risk by cancer endpoint (stomach, pancreas, lung, leukemia, all other). Results: There are statistically significant (P<.05) excess risks for all cancer and for lung cancer and borderline statistically significant risks for stomach cancer (P=.07), and leukemia (P=.06), with excess relative risks Gy{sup -1} of 0.024 (95% confidence interval [CI] 0.011, 0.039), 0.559 (95% CI 0.221, 1.021), 0.042 (95% CI -0.002, 0.119), and 1.087 (95% CI -0.018, 4.925), respectively. There is statistically significant (P=.007) excess risk of pancreatic cancer when adjusted for dose-response curvature. General downward curvature is apparent in the dose response, statistically significant (P<.05) for all cancers, pancreatic cancer, and all other cancers (ie, other than stomach, pancreas, lung, leukemia). There are indications of reduction in relative risk with increasing age at exposure (for all cancers, pancreatic cancer), but no evidence for quadratic variations in relative risk with age at exposure. If a linear-exponential dose response is used, there is no significant heterogeneity in the dose response among the 5 endpoints considered or in the speed of variation of relative risk with age at exposure. The risks are generally consistent with those observed in the Japanese atomic bomb survivors and in groups of nuclear workers. Conclusions: There are excess risks for various malignancies in this data set. Generally there is a marked downward curvature in the dose response and significant reduction in relative risk with increasing age at exposure. The consistency of risks with those observed in the Japanese atomic bomb survivors and in groups of nuclear workers implies that there may be little sparing effect of fractionation of dose or low-dose-rate exposure.

  20. Individualized Dose Prescription for Hypofractionation in Advanced Non-Small-Cell Lung Cancer Radiotherapy: An in silico Trial

    SciTech Connect (OSTI)

    Hoffmann, Aswin L.; Troost, Esther G.C.; Huizenga, Henk; Kaanders, Johannes H.A.M. [Radboud University Nijmegen Medical Centre, Department of Radiation Oncology, Nijmegen (Netherlands); Bussink, Johan, E-mail: j.bussink@rther.umcn.nl [Radboud University Nijmegen Medical Centre, Department of Radiation Oncology, Nijmegen (Netherlands)] [Radboud University Nijmegen Medical Centre, Department of Radiation Oncology, Nijmegen (Netherlands)

    2012-08-01T23:59:59.000Z

    Purpose: Local tumor control and outcome remain poor in patients with advanced non-small-cell lung cancer (NSCLC) treated by external beam radiotherapy. We investigated the therapeutic gain of individualized dose prescription with dose escalation based on normal tissue dose constraints for various hypofractionation schemes delivered with intensity-modulated radiation therapy. Methods and Materials: For 38 Stage III NSCLC patients, the dose level of an existing curative treatment plan with standard fractionation (66 Gy) was rescaled based on dose constraints for the lung, spinal cord, esophagus, brachial plexus, and heart. The effect on tumor total dose (TTD) and biologic tumor effective dose in 2-Gy fractions (TED) corrected for overall treatment time (OTT) was compared for isotoxic and maximally tolerable schemes given in 15, 20, and 33 fractions. Rescaling was accomplished by altering the dose per fraction and/or the number of fractions while keeping the relative dose distribution of the original treatment plan. Results: For 30 of the 38 patients, dose escalation by individualized hypofractionation yielded therapeutic gain. For the maximally tolerable dose scheme in 33 fractions (MTD{sub 33}), individualized dose escalation resulted in a 2.5-21% gain in TTD. In the isotoxic schemes, the number of fractions could be reduced with a marginal increase in TED. For the maximally tolerable dose schemes, the TED could be escalated up to 36.6%, and for all patients beyond the level of the isotoxic and the MTD{sub 33} schemes (range, 3.3-36.6%). Reduction of the OTT contributed to the therapeutic gain of the shortened schemes. For the maximally tolerable schemes, the maximum esophageal dose was the dominant dose-limiting constraint in most patients. Conclusions: This modeling study showed that individualized dose prescription for hypofractionation in NSCLC radiotherapy, based on scaling of existing treatment plans up to normal tissue dose constraints, enables dose escalation with therapeutic gain in 79% of the cases.

  1. Intensity-modulated radiotherapy improves lymph node coverage and dose to critical structures compared with three-dimensional conformal radiation therapy in clinically localized prostate cancer

    SciTech Connect (OSTI)

    Wang-Chesebro, Alice [Radiation Oncology, University of California-San Francisco, San Francisco, CA (United States)]. E-mail: awang@radonc17.ucsf.edu; Xia Ping [Radiation Oncology, University of California-San Francisco, San Francisco, CA (United States); Coleman, Joy [Radiation Oncology, University of California-San Francisco, San Francisco, CA (United States); Akazawa, Clayton C. [Radiation Oncology, University of California-San Francisco, San Francisco, CA (United States); Roach, Mack [Radiation Oncology, University of California-San Francisco, San Francisco, CA (United States)

    2006-11-01T23:59:59.000Z

    Purpose: The aim of this study was to quantify gains in lymph node coverage and critical structure dose reduction for whole-pelvis (WP) and extended-field (EF) radiotherapy in prostate cancer using intensity-modulated radiotherapy (IMRT) compared with three-dimensional conformal radiotherapy (3DCRT) for the first treatment phase of 45 Gy in the concurrent treatment of lymph nodes and prostate. Methods and Materials: From January to August 2005, 35 patients with localized prostate cancer were treated with pelvic IMRT; 7 had nodes defined up to L5-S1 (Group 1), and 28 had nodes defined above L5-S1 (Group 2). Each patient had 2 plans retrospectively generated: 1 WP 3DCRT plan using bony landmarks, and 1 EF 3DCRT plan to cover the vascular defined volumes. Dose-volume histograms for the lymph nodes, rectum, bladder, small bowel, and penile bulb were compared by group. Results: For Group 1, WP 3DCRT missed 25% of pelvic nodes with the prescribed dose 45 Gy and missed 18% with the 95% prescribed dose 42.75 Gy, whereas WP IMRT achieved V{sub 45Gy} = 98% and V{sub 42.75Gy} = 100%. Compared with WP 3DCRT, IMRT reduced bladder V{sub 45Gy} by 78%, rectum V{sub 45Gy} by 48%, and small bowel V{sub 45Gy} by 232 cm{sup 3}. EF 3DCRT achieved 95% coverage of nodes for all patients at high cost to critical structures. For Group 2, IMRT decreased bladder V{sub 45Gy} by 90%, rectum V{sub 45Gy} by 54% and small bowel V{sub 45Gy} by 455 cm{sup 3} compared with EF 3DCRT. Conclusion: In this study WP 3DCRT missed a significant percentage of pelvic nodes. Although EF 3DCRT achieved 95% pelvic nodal coverage, it increased critical structure doses. IMRT improved pelvic nodal coverage while decreasing dose to bladder, rectum, small bowel, and penile bulb. For patients with extended node involvement, IMRT especially decreases small bowel dose.

  2. Hanford Environmental Dose Reconstruction Project. Monthly report

    SciTech Connect (OSTI)

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

    1992-10-01T23:59:59.000Z

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

  3. Hanford Environmental Dose Reconstruction Project Monthly Report

    SciTech Connect (OSTI)

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

    1992-03-01T23:59:59.000Z

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

  4. Hanford Environmental Dose Reconstruction Project. Monthly report

    SciTech Connect (OSTI)

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

    1992-04-01T23:59:59.000Z

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

  5. Hanford Environmental Dose Reconstruction Project

    SciTech Connect (OSTI)

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

    1992-07-01T23:59:59.000Z

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

  6. Prediction of the mortality dose-response relationship in man

    SciTech Connect (OSTI)

    Morris, M.D.; Jones, T.D.

    1987-01-01T23:59:59.000Z

    Based upon an extensive data base including 100 separate animal studies, an estimate of the mortality dose-response relationship due to continuous photon radiation is predicted for 70 kg man. The model used in this prediction exercise includes fixed terms accounting for effects of body weight and dose rate, and random terms accounting for inter- and intra-species variation and experimental error. Point predictions and 95% prediction intervals are given for the LD/sub 05/, LD/sub 10/, LD/sub 25/, LD/sub 50/, LD/sub 75/, LD/sub 90/, and LD/sub 95/, for dose rates ranging from 1 to 50 R/min. 6 refs., 5 tabs.

  7. Organ doses for reference adult male and female undergoing computed tomography estimated by Monte Carlo simulations

    SciTech Connect (OSTI)

    Lee, Choonsik; Kim, Kwang Pyo; Long, Daniel; Fisher, Ryan; Tien, Chris; Simon, Steven L.; Bouville, Andre; Bolch, Wesley E. [Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institute of Health, Bethesda, Maryland 20852 (United States); Department of Nuclear Engineering, Kyung Hee University, Yongin 446-701 (Korea, Republic of); Department of Nuclear and Radiological Engineering, University of Florida, Gainesville, Florida 32611 (United States); Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institute of Health, Bethesda, Maryland 20852 (United States); Department of Nuclear and Radiological Engineering, University of Florida, Gainesville, Florida 32611 (United States)

    2011-03-15T23:59:59.000Z

    Purpose: To develop a computed tomography (CT) organ dose estimation method designed to readily provide organ doses in a reference adult male and female for different scan ranges to investigate the degree to which existing commercial programs can reasonably match organ doses defined in these more anatomically realistic adult hybrid phantomsMethods: The x-ray fan beam in the SOMATOM Sensation 16 multidetector CT scanner was simulated within the Monte Carlo radiation transport code MCNPX2.6. The simulated CT scanner model was validated through comparison with experimentally measured lateral free-in-air dose profiles and computed tomography dose index (CTDI) values. The reference adult male and female hybrid phantoms were coupled with the established CT scanner model following arm removal to simulate clinical head and other body region scans. A set of organ dose matrices were calculated for a series of consecutive axial scans ranging from the top of the head to the bottom of the phantoms with a beam thickness of 10 mm and the tube potentials of 80, 100, and 120 kVp. The organ doses for head, chest, and abdomen/pelvis examinations were calculated based on the organ dose matrices and compared to those obtained from two commercial programs, CT-EXPO and CTDOSIMETRY. Organ dose calculations were repeated for an adult stylized phantom by using the same simulation method used for the adult hybrid phantom. Results: Comparisons of both lateral free-in-air dose profiles and CTDI values through experimental measurement with the Monte Carlo simulations showed good agreement to within 9%. Organ doses for head, chest, and abdomen/pelvis scans reported in the commercial programs exceeded those from the Monte Carlo calculations in both the hybrid and stylized phantoms in this study, sometimes by orders of magnitude. Conclusions: The organ dose estimation method and dose matrices established in this study readily provides organ doses for a reference adult male and female for different CT scan ranges and technical parameters. Organ doses from existing commercial programs do not reasonably match organ doses calculated for the hybrid phantoms due to differences in phantom anatomy, as well as differences in organ dose scaling parameters. The organ dose matrices developed in this study will be extended to cover different technical parameters, CT scanner models, and various age groups.

  8. Millimeter Wave Sensor Technologies Track Biometrics; Detect Chemicals, Gases, and Radiation: Argonne’s millimeter wave (mmW) sensor technologies measure a wide range of threat materials remotely

    Energy Innovation Portal (Marketing Summaries) [EERE]

    2013-04-15T23:59:59.000Z

    Security threats come in many forms—airborne, radiative, gaseous, human, or infiltrative—and it can be costly and impractical to deploy a broad suite of detector technologies to identify all potential hazards in public places. Argonne’s millimeter wave (mmW) sensor technologies measure a wide range of threat materials remotely, making them well suited to many security, industrial and medical applications....

  9. Retrospective Evaluation Reveals That Long-term Androgen Deprivation Therapy Improves Cause-Specific and Overall Survival in the Setting of Dose-Escalated Radiation for High-Risk Prostate Cancer

    SciTech Connect (OSTI)

    Feng, Felix Y., E-mail: ffeng@med.umich.edu [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States); Department of Radiation Oncology, Veterans Affairs Medical Center, Ann Arbor, Michigan (United States); Blas, Kevin; Olson, Karin; Stenmark, Matthew [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States)] [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States); Sandler, Howard [Cedars Sinai Medical Center, Los Angeles, California (United States)] [Cedars Sinai Medical Center, Los Angeles, California (United States); Hamstra, Daniel A. [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States)] [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States)

    2013-05-01T23:59:59.000Z

    Purpose: To evaluate the role of androgen deprivation therapy (ADT) and duration for high-risk prostate cancer patients treated with dose-escalated radiation therapy (RT). Methods and Materials: A retrospective analysis of high-risk prostate cancer patients treated with dose-escalated RT (minimum 75 Gy) with or without ADT was performed. The relationship between ADT use and duration with biochemical failure (BF), metastatic failure (MF), prostate cancer-specific mortality (PCSM), non-prostate cancer death (NPCD), and overall survival (OS) was assessed as a function of pretreatment characteristics, comorbid medical illness, and treatment using Fine and Gray's cumulative incidence methodology. Results: The median follow-up time was 64 months. In men with National Comprehensive Cancer Network defined high-risk prostate cancer treated with dose-escalated RT, on univariate analysis, both metastasis (P<.0001; hazard ratio 0.34; 95% confidence interval 0.18-0.67; cumulative incidence at 60 months 13% vs 35%) and PCSM (P=.015; hazard ratio 0.41; 95% confidence interval 0.2-1.0; cumulative incidence at 60 months 6% vs 11%) were improved with the use of ADT. On multivariate analysis for all high-risk patients, Gleason score was the strongest negative prognostic factor, and long-term ADT (LTAD) improved MF (P=.002), PCSM (P=.034), and OS (P=.001). In men with prostate cancer and Gleason scores 8 to 10, on multivariate analysis after adjustment for other risk features, there was a duration-dependent improvement in BF, metastasis, PCSM, and OS, all favoring LTAD in comparison with STAD or RT alone. Conclusion: For men with high-risk prostate cancer treated with dose-escalated EBRT, this retrospective study suggests that the combination of LTAD and RT provided a significant improvement in clinical outcome, which was especially true for those with Gleason scores of 8 to 10.

  10. DOE 2010 Occupational Radiation Exposure November 2011

    SciTech Connect (OSTI)

    U.S. Department of Energy, Office of Health, Safety and Security, Office of Analysis

    2011-11-11T23:59:59.000Z

    This report discusses radiation protection and dose reporting requirements, presents the 2010 occupational radiation dose data trended over the past 5 years, and includes instructions to submit successful ALARA projects.

  11. Evaluation of pelletron accelerator facility to study radiation effects on semiconductor devices

    SciTech Connect (OSTI)

    Prakash, A. P. Gnana; Pushpa, N.; Praveen, K. C.; Naik, P. S.; Revannasiddaiah, D. [Department of Studies in Physics, University of Mysore, Manasagangotri, Mysore-570006, Karnataka (India)

    2012-06-05T23:59:59.000Z

    In this paper we present the comprehensive results on the effects of different radiation on the electrical characteristics of different semiconductor devices like Si BJT, n-channel MOSFETs, 50 GHz and 200 GHz silicon-germanium heterojunction bipolar transistor (SiGe HBTs). The total dose effects of different radiation are compared in the same total dose ranging from 100 krad to 100 Mrad. We show that the irradiation time needed to reach very high total dose can be reduced by using Pelletron accelerator facilities instead of conventional irradiation facilities.

  12. Use of 4-Dimensional Computed Tomography-Based Ventilation Imaging to Correlate Lung Dose and Function With Clinical Outcomes

    SciTech Connect (OSTI)

    Vinogradskiy, Yevgeniy, E-mail: yevgeniy.vinogradskiy@ucdenver.edu [Department of Radiation Oncology, University of Colorado School of Medicine, Aurora, Colorado (United States)] [Department of Radiation Oncology, University of Colorado School of Medicine, Aurora, Colorado (United States); Castillo, Richard [Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States)] [Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Castillo, Edward [Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States) [Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Department of Computational and Applied Mathematics, Rice University, Houston, Texas (United States); Tucker, Susan L. [Departments of Bioinformatics and Computational Biology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States)] [Departments of Bioinformatics and Computational Biology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Liao, Zhongxing [Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States)] [Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Guerrero, Thomas [Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States) [Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Department of Computational and Applied Mathematics, Rice University, Houston, Texas (United States); Martel, Mary K. [Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States)] [Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States)

    2013-06-01T23:59:59.000Z

    Purpose: Four-dimensional computed tomography (4DCT)-based ventilation is an emerging imaging modality that can be used in the thoracic treatment planning process. The clinical benefit of using ventilation images in radiation treatment plans remains to be tested. The purpose of the current work was to test the potential benefit of using ventilation in treatment planning by evaluating whether dose to highly ventilated regions of the lung resulted in increased incidence of clinical toxicity. Methods and Materials: Pretreatment 4DCT data were used to compute pretreatment ventilation images for 96 lung cancer patients. Ventilation images were calculated using 4DCT data, deformable image registration, and a density-change based algorithm. Dose–volume and ventilation-based dose function metrics were computed for each patient. The ability of the dose–volume and ventilation-based dose–function metrics to predict for severe (grade 3+) radiation pneumonitis was assessed using logistic regression analysis, area under the curve (AUC) metrics, and bootstrap methods. Results: A specific patient example is presented that demonstrates how incorporating ventilation-based functional information can help separate patients with and without toxicity. The logistic regression significance values were all lower for the dose–function metrics (range P=.093-.250) than for their dose–volume equivalents (range, P=.331-.580). The AUC values were all greater for the dose–function metrics (range, 0.569-0.620) than for their dose–volume equivalents (range, 0.500-0.544). Bootstrap results revealed an improvement in model fit using dose–function metrics compared to dose–volume metrics that approached significance (range, P=.118-.155). Conclusions: To our knowledge, this is the first study that attempts to correlate lung dose and 4DCT ventilation-based function to thoracic toxicity after radiation therapy. Although the results were not significant at the .05 level, our data suggests that incorporating ventilation-based functional imaging can improve prediction for radiation pneumonitis. We present an important first step toward validating the use of 4DCT-based ventilation imaging in thoracic treatment planning.

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

    SciTech Connect (OSTI)

    Baker, D. A.

    1980-10-01T23:59:59.000Z

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

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

    SciTech Connect (OSTI)

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

    1982-12-01T23:59:59.000Z

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

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

    SciTech Connect (OSTI)

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

    1982-06-01T23:59:59.000Z

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

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

    SciTech Connect (OSTI)

    Baker, D.A.

    1988-08-01T23:59:59.000Z

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

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

    SciTech Connect (OSTI)

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

    1989-10-01T23:59:59.000Z

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

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

    SciTech Connect (OSTI)

    Baker, D.A.

    1988-01-01T23:59:59.000Z

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

  19. COLUMBIA UNIVERSITY Radiation Safety Program

    E-Print Network [OSTI]

    Jia, Songtao

    for increased protection from ionizing radiation for declared pregnant radiation workers. The radiation doseCOLUMBIA UNIVERSITY Radiation Safety Program Medical Center - T: 212-305-0303 F: 212 regulations of the Rules of the City of New York, Article 175, Radiation Control, there is a requirement

  20. High dynamic range measurement of spectral responsivity and linearity of a radiation thermometer using a super-continuum laser and LEDs

    SciTech Connect (OSTI)

    Yoo, Y. S.; Lee, D. H.; Park, C. W.; Park, S. N. [Korea Research Institute of Standards and Science 209 Gajeong-Ro, Yuseong-Gu, Daejon 305-340 (Korea, Republic of)] [Korea Research Institute of Standards and Science 209 Gajeong-Ro, Yuseong-Gu, Daejon 305-340 (Korea, Republic of)

    2013-09-11T23:59:59.000Z

    To realize the temperature scale above the freezing point of silver according to the definition of ITS-90, the dynamic range of the spectral responsivity is one of the most important factors which limit its uncertainty. When the residual spectral response at both side bands of a spectral band is not negligible, a significant uncertainty can be caused by a low dynamic range of the spectral responsivity measurement. In general, incandescent lamps are used to measure the spectral responsivity and the linearity. The dynamic range of the spectral responsivity measurement is often limited by a trade-off with the desired spectral resolution, which is less than 6 decades. Nonlinearity is another limiting fact of uncertainties of the temperature scale. Tungsten lamps have disadvantage in the nonlinearity measurements in terms of adjustability of radiance level and spectral selectivity. We report spectral responsivity measurements of which the measurable dynamic range is enhanced 50 times after replacing a QTH lamp with a super continuum laser. We also present a spectrally selected linearity measurement over a wide dynamic range using high-brightness light emitting diode arrays to observe a slight saturation of linearity.

  1. The effect of thymosin on the survival of CBA/J mice exposed to lethal and acute doses of ionizing radiation

    E-Print Network [OSTI]

    Huchton, Roger Lynn

    1978-01-01T23:59:59.000Z

    and after 875 R whole-body X-radiatron to two groups of 15 mice. Control groups recexved equivalent amounts of sterile saline in corresponding treatment regimens. Though a slight decrease zn the mean time-to-death for the thymosin-in7ected au. ce... was noted, the difference in the mean time-to-deaths for the two groups was not significantly different. For the second investigation, two groups of 18 mice were exposed to 700 R whole-body X-radiation. Daily subcutaneous injections of thymosrn were...

  2. Organ doses, effective doses, and risk indices in adult CT: Comparison of four types of reference phantoms across different examination protocols

    SciTech Connect (OSTI)

    Zhang Yakun; Li Xiang; Paul Segars, W.; Samei, Ehsan [Medical Physics Graduate Program, Duke University, Durham, North Carolina 27705 and Carl E. Ravin Advanced Imaging Laboratories, Duke University, Durham, North Carolina 27705 (United States); Carl E. Ravin Advanced Imaging Laboratories, Duke University, Durham, North Carolina 27705 and Department of Radiology, Duke University, Durham, North Carolina 27705 (United States); Medical Physics Graduate Program, Duke University, Durham, North Carolina 27705 (United States); Carl E. Ravin Advanced Imaging Laboratories, Duke University, Durham, North Carolina 27705 (United States) and Department of Radiology, Duke University, Durham, North Carolina 27705 (United States); Medical Physics Graduate Program, Duke University, Durham, North Carolina 27705 (United States); Carl E. Ravin Advanced Imaging Laboratories, Duke University, Durham, North Carolina 27705 (United States); Department of Radiology, Duke University, Durham, North Carolina 27705 (United States) and Departments of Physics, Biomedical Engineering, and Electrical and Computer Engineering, Duke University, Durham, North Carolina 27705 (United States)

    2012-06-15T23:59:59.000Z

    Purpose: Radiation exposure from computed tomography (CT) to the public has increased the concern among radiation protection professionals. Being able to accurately assess the radiation dose patients receive during CT procedures is a crucial step in the management of CT dose. Currently, various computational anthropomorphic phantoms are used to assess radiation dose by different research groups. It is desirable to better understand how the dose results are affected by different choices of phantoms. In this study, the authors assessed the uncertainties in CT dose and risk estimation associated with different types of computational phantoms for a selected group of representative CT protocols. Methods: Routinely used CT examinations were categorized into ten body and three neurological examination categories. Organ doses, effective doses, risk indices, and conversion coefficients to effective dose and risk index (k and q factors, respectively) were estimated for these examinations for a clinical CT system (LightSpeed VCT, GE Healthcare). Four methods were used, each employing a different type of reference phantoms. The first and second methods employed a Monte Carlo program previously developed and validated in our laboratory. In the first method, the reference male and female extended cardiac-torso (XCAT) phantoms were used, which were initially created from the Visible Human data and later adjusted to match organ masses defined in ICRP publication 89. In the second method, the reference male and female phantoms described in ICRP publication 110 were used, which were initially developed from tomographic data of two patients and later modified to match ICRP 89 organ masses. The third method employed a commercial dosimetry spreadsheet (ImPACT group, London, England) with its own hermaphrodite stylized phantom. In the fourth method, another widely used dosimetry spreadsheet (CT-Expo, Medizinische Hochschule, Hannover, Germany) was employed together with its associated male and female stylized phantoms. Results: For fully irradiated organs, average coefficients of variation (COV) ranged from 0.07 to 0.22 across the four male phantoms and from 0.06 to 0.18 across the four female phantoms; for partially irradiated organs, average COV ranged from 0.13 to 0.30 across the four male phantoms and from 0.15 to 0.30 across the four female phantoms. Doses to the testes, breasts, and esophagus showed large variations between phantoms. COV for gender-averaged effective dose and k factor ranged from 0.03 to 0.23 and from 0.06 to 0.30, respectively. COV for male risk index and q factor ranged from 0.06 to 0.30 and from 0.05 to 0.36, respectively; COV for female risk index and q factor ranged from 0.06 to 0.49 and from 0.07 to 0.54, respectively. Conclusions: Despite closely matched organ mass, total body weight, and height, large differences in organ dose exist due to variation in organ location, spatial distribution, and dose approximation method. Dose differences for fully irradiated radiosensitive organs were much smaller than those for partially irradiated organs. Weighted dosimetry quantities including effective dose, male risk indices, k factors, and male q factors agreed well across phantoms. The female risk indices and q factors varied considerably across phantoms.

  3. Method for microbeam radiation therapy

    DOE Patents [OSTI]

    Slatkin, D.N.; Dilmanian, F.A.; Spanne, P.O.

    1994-08-16T23:59:59.000Z

    A method is disclosed of performing radiation therapy on a patient, involving exposing a target, usually a tumor, to a therapeutic dose of high energy electromagnetic radiation, preferably X-ray radiation. The dose is in the form of at least two non-overlapping microbeams of radiation, each microbeam having a width of less than about 1 millimeter. Target tissue exposed to the microbeams receives a radiation dose during the exposure that exceeds the maximum dose that such tissue can survive. Non-target tissue between the microbeams receives a dose of radiation below the threshold amount of radiation that can be survived by the tissue, and thereby permits the non-target tissue to regenerate. The microbeams may be directed at the target from one direction, or from more than one direction in which case the microbeams overlap within the target tissue enhancing the lethal effect of the irradiation while sparing the surrounding healthy tissue. No Drawings

  4. SM22{alpha}-induced activation of p16{sup INK4a}/retinoblastoma pathway promotes cellular senescence caused by a subclinical dose of {gamma}-radiation and doxorubicin in HepG2 cells

    SciTech Connect (OSTI)

    Kim, Tae Rim; Lee, Hee Min; Lee, So Yong; Kim, Eun Jin; Kim, Kug Chan [Department of Radiation Biology, Environmental Radiation Research Group, Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)] [Department of Radiation Biology, Environmental Radiation Research Group, Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Paik, Sang Gi [Department of Biology, School of Biosciences and Biotechnology, Chungnam National University, Daejeon (Korea, Republic of)] [Department of Biology, School of Biosciences and Biotechnology, Chungnam National University, Daejeon (Korea, Republic of); Cho, Eun Wie, E-mail: ewcho@kribb.re.kr [Daejeon-KRIBB-FHCRC Cooperation Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon (Korea, Republic of); Kim, In Gyu, E-mail: igkim@kaeri.re.kr [Department of Radiation Biology, Environmental Radiation Research Group, Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2010-09-10T23:59:59.000Z

    Research highlights: {yields} SM22{alpha} overexpression in HepG2 cells leads cells to a growth arrest state, and the treatment of a subclinical dose of {gamma}-radiation or doxorubicin promotes cellular senescence. {yields} SM22{alpha} overexpression elevates p16{sup INK4a} followed by pRB activation, but there are no effects on p53/p21{sup WAF1/Cip1} pathway. {yields} SM22{alpha}-induced MT-1G activates p16{sup INK4a}/pRB pathway, which promotes cellular senescence by damaging agents. -- Abstract: Smooth muscle protein 22-alpha (SM22{alpha}) is known as a transformation- and shape change-sensitive actin cross-linking protein found in smooth muscle tissue and fibroblasts; however, its functional role remains uncertain. We reported previously that SM22{alpha} overexpression confers resistance against anti-cancer drugs or radiation via induction of metallothionein (MT) isozymes in HepG2 cells. In this study, we demonstrate that SM22{alpha} overexpression leads cells to a growth arrest state and promotes cellular senescence caused by treatment with a subclinical dose of {gamma}-radiation (0.05 and 0.1 Gy) or doxorubicin (0.01 and 0.05 {mu}g/ml), compared to control cells. Senescence growth arrest is known to be controlled by p53 phosphorylation/p21{sup WAF1/Cip1} induction or p16{sup INK4a}/retinoblastoma protein (pRB) activation. SM22{alpha} overexpression in HepG2 cells elevated p16{sup INK4a} followed by pRB activation, but did not activate the p53/p21{sup WAF1/Cip1} pathway. Moreover, MT-1G, which is induced by SM22{alpha} overexpression, was involved in the activation of the p16{sup INK4a}/pRB pathway, which led to a growth arrest state and promoted cellular senescence caused by damaging agents. Our findings provide the first demonstration that SM22{alpha} modulates cellular senescence caused by damaging agents via regulation of the p16{sup INK4a}/pRB pathway in HepG2 cells and that these effects of SM22{alpha} are partially mediated by MT-1G.

  5. Metabolomic Response of Human Skin Tissue to Low Dose Ionizing...

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

    for IR exposure at low doses can help provide a scientific basis for establishing radiation protection standards. Little is known regarding the physiological responses to...

  6. A Radiation-Hard Dual Channel 4-bit Pipeline for a 12-bit 40 MS/s ADC Prototype with extended Dynamic Range for the ATLAS Liquid Argon Calorimeter Readout Electronics Upgrade at the CERN LHC

    E-Print Network [OSTI]

    Jayanth Kuppambatti; Jaroslav Ban; Timothy Andeen; Peter Kinget; Gustaaf Brooijmans

    2013-07-31T23:59:59.000Z

    The design of a radiation-hard dual channel 12-bit 40 MS/s pipeline ADC with extended dynamic range is presented, for use in the readout electronics upgrade for the ATLAS Liquid Argon Calorimeters at the CERN Large Hadron Collider. The design consists of two pipeline A/D channels with four Multiplying Digital-to-Analog Converters with nominal 12-bit resolution each. The design, fabricated in the IBM 130 nm CMOS process, shows a performance of 68 dB SNDR at 18 MHz for a single channel at 40 MS/s while consuming 55 mW/channel from a 2.5 V supply, and exhibits no performance degradation after irradiation. Various gain selection algorithms to achieve the extended dynamic range are implemented and tested.

  7. A mm-Scale Dosimetry System Based on Optically Stimulated Luminescence of Beryllium Oxide for Investigation of Dose Rate Profiles in Constricted Environments - 12219

    SciTech Connect (OSTI)

    Sommer, Marian; Jahn, Axel; Sommer, Dora; Henniger, Juergen [Technische Universitaet Dresden, Institute for Nuclear and Particle Physics, Radiation Physics Group, D-01062 Dresden (Germany); Praetorius, Reiner M. [Wiederaufarbeitungsanlage Karlsruhe Rueckbau- und Entsorgungs- GmbH, POB 1263, D-76339 Eggenstein-Leopoldshafen (Germany)

    2012-07-01T23:59:59.000Z

    The dismantling of the former German fuel reprocessing research center Wiederaufbeitungsanlage Karlsruhe requires extensive investigations of contamination and dose rate inside of the shielded areas. Particularly for first the exploration of radiation field existing thermo-element pipes may offer access to the tanks and to other interesting points without the risk of contamination. Because of their small dimension, almost no active dosimetry systems are able to measure inside the pipes. New mm-scale luminescence dosimeters in combination with a packing and transport technique are presented. The dosimeters could measure doses from 0.1 mGy up to more than 100 Gy. Hence, over the possible exposure time durations, dose rates from ?Gyh{sup -1} up to 1000 Gyh{sup -1} are ascertainable. For potential users the system opens the opportunity for investigation of dose rates inside of shielding and in contaminated environments. Particularly in constricted environments the technique is a unique solution for dose and dose rate measurement tasks. Within the linear dose range up to several ten Gy, the uncertainty of the results is less than 5%. 100 Gy-doses can be specified within 20%, with individual high dose calibration of the detectors even better. For WAK and other potential users the system offers the opportunity to investigate dose rates inside of shieldings and in contaminated environments. Particularly in constricted environments the technique is an unique solution for dose and dose rate measurements. (authors)

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

    SciTech Connect (OSTI)

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

    1990-08-01T23:59:59.000Z

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

  9. Gamma radiation field intensity meter

    DOE Patents [OSTI]

    Thacker, L.H.

    1994-08-16T23:59:59.000Z

    A gamma radiation intensity meter measures dose rate of a radiation field. The gamma radiation intensity meter includes a tritium battery emitting beta rays generating a current which is essentially constant. Dose rate is correlated to an amount of movement of an electroscope element charged by the tritium battery. Ionizing radiation decreases the voltage at the element and causes movement. A bleed resistor is coupled between the electroscope support element or electrode and the ionization chamber wall electrode. 4 figs.

  10. Gamma radiation field intensity meter

    DOE Patents [OSTI]

    Thacker, Louis H. (Knoxville, TN)

    1995-01-01T23:59:59.000Z

    A gamma radiation intensity meter measures dose rate of a radiation field. The gamma radiation intensity meter includes a tritium battery emitting beta rays generating a current which is essentially constant. Dose rate is correlated to an amount of movement of an electroscope element charged by the tritium battery. Ionizing radiation decreases the voltage at the element and causes movement. A bleed resistor is coupled between the electroscope support element or electrode and the ionization chamber wall electrode.

  11. Gamma radiation field intensity meter

    DOE Patents [OSTI]

    Thacker, L.H.

    1995-10-17T23:59:59.000Z

    A gamma radiation intensity meter measures dose rate of a radiation field. The gamma radiation intensity meter includes a tritium battery emitting beta rays generating a current which is essentially constant. Dose rate is correlated to an amount of movement of an electroscope element charged by the tritium battery. Ionizing radiation decreases the voltage at the element and causes movement. A bleed resistor is coupled between the electroscope support element or electrode and the ionization chamber wall electrode. 4 figs.

  12. Gamma radiation field intensity meter

    DOE Patents [OSTI]

    Thacker, Louis H. (Knoxville, TN)

    1994-01-01T23:59:59.000Z

    A gamma radiation intensity meter measures dose rate of a radiation field. The gamma radiation intensity meter includes a tritium battery emitting beta rays generating a current which is essentially constant. Dose rate is correlated to an amount of movement of an electroscope element charged by the tritium battery. Ionizing radiation decreases the voltage at the element and causes movement. A bleed resistor is coupled between the electroscope support element or electrode and the ionization chamber wall electrode.

  13. Radiation Safety Manual Dec 2012 Page 1 RADIATION SAFETY

    E-Print Network [OSTI]

    Grishok, Alla

    of External and Internal Doses E. Reports and Notices to Workers Chapter VII: Radiation ProtectionRadiation Safety Manual ­ Dec 2012 Page 1 RADIATION SAFETY MANUAL For Columbia University NewYork-Presbyterian Hospital New York State Psychiatric Institute Barnard College December 2012 #12;Radiation Safety Manual

  14. AGING FACILITY WORKER DOSE ASSESSMENT

    SciTech Connect (OSTI)

    R.L. Thacker

    2005-03-24T23:59:59.000Z

    The purpose of this calculation is to estimate radiation doses received by personnel working in the Aging Facility performing operations to transfer aging casks to the aging pads for thermal and logistical management, stage empty aging casks, and retrieve aging casks from the aging pads for further processing in other site facilities. Doses received by workers due to aging cask surveillance and maintenance operations are also included. The specific scope of work contained in this calculation covers both collective doses and individual worker group doses on an annual basis, and includes the contributions due to external and internal radiation from normal operation. There are no Category 1 event sequences associated with the Aging Facility (BSC 2004 [DIRS 167268], Section 7.2.1). The results of this calculation will be used to support the design of the Aging Facility and to provide occupational dose estimates for the License Application. The calculations contained in this document were developed by Environmental and Nuclear Engineering of the Design and Engineering Organization and are intended solely for the use of the Design and Engineering Organization in its work regarding facility operation. Yucca Mountain Project personnel from the Environmental and Nuclear Engineering should be consulted before use of the calculations for purposes other than those stated herein or use by individuals other than authorized personnel in Environmental and Nuclear Engineering.

  15. Dose profiles through the dermis for on and off-skin hot particle exposures

    E-Print Network [OSTI]

    Shaw, Kimberly Rochelle

    1993-01-01T23:59:59.000Z

    compared to gamma-rays. Gamma-rays are monoenergetic photons with energies ranging from a few keV to several MeV. Unlike beta particles, gamma-rays are indirectly ionizing radiation. Because a gamma-ray is uncharged, it undergoes no direct ionization... detailed data on dose profiles This thesis follows the format of Radiation Protection Dosimetry. through the dermis from fuel fragments or from mixed beta-gamma activation products. The effects of beta-emitting hot particles suspended above skin without...

  16. Hanford Environmental Dose Reconstruction Project Monthly Report

    SciTech Connect (OSTI)

    Finch, S.M. (comp.)

    1990-01-01T23:59:59.000Z

    The objective of the Hanford Environmental Dose Reconstruction Project is to estimate the radiation doses that populations could have received from nuclear operations at Hanford since 1944. The project is being managed and conducted by the Pacific Northwest Laboratory (PNL) under the direction of an independent Technical Steering Panel (TSP). The project is divided into the following technical tasks. These tasks correspond to the path radionuclides followed, from release to impact on humans (dose estimates): source terms; environmental transport; environmental monitoring data; demographics; agriculture; food habits; and environmental pathways and dose estimates. 3 figs.

  17. Multiple anatomy optimization of accumulated dose

    SciTech Connect (OSTI)

    Watkins, W. Tyler, E-mail: watkinswt@virginia.edu; Siebers, Jeffrey V. [Department of Radiation Oncology, University of Virginia, Charlottesville, Virginia 22908 and Department of Radiation Oncology, Virginia Commonwealth University, Richmond, Virginia 23298 (United States); Moore, Joseph A. [Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins University, Baltimore, Maryland 21231 and Department of Radiation Oncology, Virginia Commonwealth University, Richmond, Virginia 23298 (United States); Gordon, James [Henry Ford Health System, Detroit, Michigan 48202 and Department of Radiation Oncology, Virginia Commonwealth University, Richmond, Virginia 23298 (United States); Hugo, Geoffrey D. [Department of Radiation Oncology, Virginia Commonwealth University, Richmond, Virginia 23298 (United States)

    2014-11-01T23:59:59.000Z

    Purpose: To investigate the potential advantages of multiple anatomy optimization (MAO) for lung cancer radiation therapy compared to the internal target volume (ITV) approach. Methods: MAO aims to optimize a single fluence to be delivered under free-breathing conditions such that the accumulated dose meets the plan objectives, where accumulated dose is defined as the sum of deformably mapped doses computed on each phase of a single four dimensional computed tomography (4DCT) dataset. Phantom and patient simulation studies were carried out to investigate potential advantages of MAO compared to ITV planning. Through simulated delivery of the ITV- and MAO-plans, target dose variations were also investigated. Results: By optimizing the accumulated dose, MAO shows the potential to ensure dose to the moving target meets plan objectives while simultaneously reducing dose to organs at risk (OARs) compared with ITV planning. While consistently superior to the ITV approach, MAO resulted in equivalent OAR dosimetry at planning objective dose levels to within 2% volume in 14/30 plans and to within 3% volume in 19/30 plans for each lung V20, esophagus V25, and heart V30. Despite large variations in per-fraction respiratory phase weights in simulated deliveries at high dose rates (e.g., treating 4/10 phases during single fraction beams) the cumulative clinical target volume (CTV) dose after 30 fractions and per-fraction dose were constant independent of planning technique. In one case considered, however, per-phase CTV dose varied from 74% to 117% of prescription implying the level of ITV-dose heterogeneity may not be appropriate with conventional, free-breathing delivery. Conclusions: MAO incorporates 4DCT information in an optimized dose distribution and can achieve a superior plan in terms of accumulated dose to the moving target and OAR sparing compared to ITV-plans. An appropriate level of dose heterogeneity in MAO plans must be further investigated.

  18. Low Dose Suppression of Neoplastic Transformation in Vitro

    SciTech Connect (OSTI)

    John Leslie Redpath

    2012-05-01T23:59:59.000Z

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

  19. Radiation effects in SYNROC-D

    SciTech Connect (OSTI)

    Van Konynenburg, R.A.; Guinan, M.W.

    1981-09-30T23:59:59.000Z

    This paper describes SYNROC-D and the irradiation it will be subjected to over the first million years of storage. This will include about 8 x 10/sup 24/ alpha decays per m/sup 3/ and a total ionization dose of about 1 x 10/sup 11/ rads. Methods of simulating the radiation effects are discussed. Previous work by others is reviewed and compared on a dpa basis. /sup 238/Pu doping experiments to simulate internal alpha decay are described, and the progress is discussed. It is concluded that dose rate effects on swelling and metamictization of perovskite and zirconolite are small over a wide range of dose rate, and that swelling and metamictization in these minerals does not anneal significantly over geological time periods.

  20. ORISE: Health Physics in Radiation Emergencies | REAC/TS Continuing...

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

    (HP), Medical Physicists (MP), Radiation Safety Officers (RSO) and others who have radiation dose assessment andor radiological control responsibilities. The course...

  1. Total ionizing dose effects of domestic SiGe HBTs under different dose rate

    E-Print Network [OSTI]

    Mo-Han, Liu; Wu-Ying, Ma; Xin, Wang; Qi, Guo; Cheng-Fa, He; Ke, Jiang; Xiao-Long, Li; Ming-Zhu, Xiong

    2015-01-01T23:59:59.000Z

    The total ionizing radiation (TID) response of commercial NPN silicon germanium hetero-junction bipolar transistors (SiGe HBTs) produced domestic were investigated under the dose rate of 800mGy(Si)/s and 1.3mGy(Si)/s with Co-60 gamma irradiation source, respectively. The changes of the transistor parameter such as Gummel characteristics, excess base current before and after irradiation are investigated. The results of the experiments shows that for the KT1151, the radiation damage have slightly difference under the different dose rate after the prolonged annealing, shows an time dependent effect(TDE). But for the KT9041, the degradations of low dose rate irradiation are more higher than the high dose rate, demonstrate that there have potential enhanced low dose rate sensitive(ELDRS) effect exist on KT9041. The underlying physical mechanisms of the different dose rates response induced by the gamma ray are detailed discussed.

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

    SciTech Connect (OSTI)

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

    1992-01-01T23:59:59.000Z

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

  3. Clinical characterization of a proton beam continuous uniform scanning system with dose layer stacking

    SciTech Connect (OSTI)

    Farr, J. B.; Mascia, A. E.; Hsi, W.-C.; Allgower, C. E.; Jesseph, F.; Schreuder, A. N.; Wolanski, M.; Nichiporov, D. F.; Anferov, V. [Indiana University, Department of Physics, Swain Hall West, Room 117, 727 E. Third St., Bloomington, Indiana 47405 and Midwest Proton Radiotherapy Institute, 2425 Milo B. Sampson Lane, Bloomington, Indiana 47408 (United States); Midwest Proton Radiotherapy Institute, 2425 Milo B. Sampson Lane, Bloomington, Indiana 47408 (United States); Indiana University Cyclotron Facility, 2401 N. Milo B. Sampson Lane, Bloomington, Indiana 47408 (United States)

    2008-11-15T23:59:59.000Z

    A proton beam delivery system on a gantry with continuous uniform scanning and dose layer stacking at the Midwest Proton Radiotherapy Institute has been commissioned and accepted for clinical use. This paper was motivated by a lack of guidance on the testing and characterization for clinical uniform scanning systems. As such, it describes how these tasks were performed with a uniform scanning beam delivery system. This paper reports the methods used and important dosimetric characteristics of radiation fields produced by the system. The commissioning data include the transverse and longitudinal dose distributions, penumbra, and absolute dose values. Using a 208 MeV cyclotron's proton beam, the system provides field sizes up to 20 and 30 cm in diameter for proton ranges in water up to 27 and 20 cm, respectively. The dose layer stacking method allows for the flexible construction of spread-out Bragg peaks with uniform modulation of up to 15 cm in water, at typical dose rates of 1-3 Gy/min. For measuring relative dose distributions, multielement ion chamber arrays, small-volume ion chambers, and radiographic films were employed. Measurements during the clinical commissioning of the system have shown that the lateral and longitudinal dose uniformity of 2.5% or better can be achieved for all clinically important field sizes and ranges. The measured transverse penumbra widths offer a slight improvement in comparison to those achieved with a double scattering beam spreading technique at the facility. Absolute dose measurements were done using calibrated ion chambers, thermoluminescent and alanine detectors. Dose intercomparisons conducted using various types of detectors traceable to a national standards laboratory indicate that the measured dosimetry data agree with each other within 5%.

  4. Population dose commitments due to radioactive releases from nuclear power plant sites in 1988. Volume 10

    SciTech Connect (OSTI)

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

    1992-01-01T23:59:59.000Z

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

  5. Experimentally studied dynamic dose interplay does not meaningfully affect target dose in VMAT SBRT lung treatments

    SciTech Connect (OSTI)

    Stambaugh, Cassandra [Department of Physics, University of South Florida, Tampa, Florida 33612 (United States)] [Department of Physics, University of South Florida, Tampa, Florida 33612 (United States); Nelms, Benjamin E. [Canis Lupus LLC, Merrimac, Wisconsin 53561 (United States)] [Canis Lupus LLC, Merrimac, Wisconsin 53561 (United States); Dilling, Thomas; Stevens, Craig; Latifi, Kujtim; Zhang, Geoffrey; Moros, Eduardo; Feygelman, Vladimir [Department of Radiation Oncology, Moffitt Cancer Center, Tampa, Florida 33612 (United States)] [Department of Radiation Oncology, Moffitt Cancer Center, Tampa, Florida 33612 (United States)

    2013-09-15T23:59:59.000Z

    Purpose: The effects of respiratory motion on the tumor dose can be divided into the gradient and interplay effects. While the interplay effect is likely to average out over a large number of fractions, it may play a role in hypofractionated [stereotactic body radiation therapy (SBRT)] treatments. This subject has been extensively studied for intensity modulated radiation therapy but less so for volumetric modulated arc therapy (VMAT), particularly in application to hypofractionated regimens. Also, no experimental study has provided full four-dimensional (4D) dose reconstruction in this scenario. The authors demonstrate how a recently described motion perturbation method, with full 4D dose reconstruction, is applied to describe the gradient and interplay effects during VMAT lung SBRT treatments.Methods: VMAT dose delivered to a moving target in a patient can be reconstructed by applying perturbations to the treatment planning system-calculated static 3D dose. Ten SBRT patients treated with 6 MV VMAT beams in five fractions were selected. The target motion (motion kernel) was approximated by 3D rigid body translation, with the tumor centroids defined on the ten phases of the 4DCT. The motion was assumed to be periodic, with the period T being an average from the empirical 4DCT respiratory trace. The real observed tumor motion (total displacement ?8 mm) was evaluated first. Then, the motion range was artificially increased to 2 or 3 cm. Finally, T was increased to 60 s. While not realistic, making T comparable to the delivery time elucidates if the interplay effect can be observed. For a single fraction, the authors quantified the interplay effect as the maximum difference in the target dosimetric indices, most importantly the near-minimum dose (D{sub 99%}), between all possible starting phases. For the three- and five-fractions, statistical simulations were performed when substantial interplay was found.Results: For the motion amplitudes and periods obtained from the 4DCT, the interplay effect is negligible (<0.2%). It is also small (0.9% average, 2.2% maximum) when the target excursion increased to 2–3 cm. Only with large motion and increased period (60 s) was a significant interplay effect observed, with D{sub 99%} ranging from 16% low to 17% high. The interplay effect was statistically significantly lower for the three- and five-fraction statistical simulations. Overall, the gradient effect dominates the clinical situation.Conclusions: A novel method was used to reconstruct the volumetric dose to a moving tumor during lung SBRT VMAT deliveries. With the studied planning and treatment technique for realistic motion periods, regardless of the amplitude, the interplay has nearly no impact on the near-minimum dose. The interplay effect was observed, for study purposes only, with the period comparable to the VMAT delivery time.

  6. Dose commitments due to radioactive releases from nuclear power plant sites in 1991. Volume 13

    SciTech Connect (OSTI)

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

    1995-04-01T23:59:59.000Z

    Population and individual radiation dose commitments have been estimated from reported radionuclide releases from commercial power reactors operating during 1991. Fifty-year dose commitments for a one-year exposure from both liquid and atmospheric releases were calculated for four population groups (infant, child, teenager and adult) residing between 2 and 80 km from each of 72 reactor sites. This report tabulates the results of these calculations, showing the dose commitments for both water and airborne pathways for each age group and organ. Also included for each of the sites is an estimate of individual doses which are compared with 10 CFR Part 50, Appendix 1 design objectives. The total collective dose commitments (from both liquid and airborne pathways) for each site ranged from a high of 22 person-rem to a low of 0.002 person-rem for the sites with plants in operation and producing power during the year. The arithmetic mean was 1.2 person-rem. The total population dose for all sites was estimated at 88 person-rem for the 130 million people considered at risk. The individual dose commitments estimated for all sites were below the Appendix 1 design objectives.

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

    SciTech Connect (OSTI)

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

    1983-08-01T23:59:59.000Z

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

  8. Dose commitments due to radioactive releases from nuclear power plant sites in 1989

    SciTech Connect (OSTI)

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

    1993-02-01T23:59:59.000Z

    Population and individual radiation dose commitments have been estimated from reported radionuclide releases from commercial power reactors operating during 1989. Fifty-year dose commitments for a one-year exposure from both liquid and atmospheric releases were calculated for four population groups (infant, child, teen-ager and adult) residing between 2 and 80 km from each of 72 reactor sites. This report tabulates the results of these calculations, showing the dose commitments for both water and airborne pathways for each age group and organ. Also included for each of the sites is an estimate of individual doses which are compared with 10 CFR Part 50, Appendix I design objectives. The total collective dose commitments (from both liquid and airborne pathways) for each site ranged from a high of 14 person-rem to a low of 0.005 person-rem for the sites with plants in operation and producing power during the year. The arithmetic mean was 1.2 person-rem. The total population dose for all sites was estimated at 84 person-rem for the 140 million people considered at risk. The individual dose commitments estimated for all sites were below the Appendix I design objectives.

  9. Dose commitments due to radioactive releases from nuclear power plant sites in 1992. Volume 14

    SciTech Connect (OSTI)

    Aaberg, R.L.; Baker, D.A.

    1996-03-01T23:59:59.000Z

    Population and individual radiation dose commitments have been estimated from reported radionuclide releases from commercial power reactors operating during 1992. Fifty-year dose commitments for a 1-year exposure from both liquid and atmospheric releases were calculated for four population groups (infant, child, teenager, and adult) residing between 2 and 80 km from each of 72 reactor sites. This report tabulates the results of these calculations, showing the dose commitments for both water and airborne pathways for each age group and organ. Also included for each of the sites is an estimate of individual doses, which are compared with 10 CFR Part 50, Appendix I, design objectives. The total collective dose commitments (from both liquid and airborne pathways) for each site ranged from a high of 3.7 person-rem to a low of 0.0015 person-rem for the sites with plants in operation and producing power during the year. The arithmetic mean was 0.66 person-rem. The total population dose for all sites was estimated at 47 person-rem for the 130-million people considered at risk. The individual dose commitments estimated for all sites were below the 10 CFR 50, Appendix I, design objectives.

  10. Enlarged longitudinal dose profiles in cone-beam CT and the need for modified dosimetry

    SciTech Connect (OSTI)

    Mori, Shinichiro; Endo, Masahiro; Nishizawa, Kanae; Tsunoo, Takanori; Aoyama, Takahiko; Fujiwara, Hideaki; Murase, Kenya [National Institute of Radiological Sciences, Chiba 263-8555 (Japan); School of Health Sciences, Nagoya University, Nagoya 461-8673 (Japan); School of Allied Health Sciences, Faculty of Medicine, Osaka University, Osaka 565-0871 (Japan)

    2005-04-01T23:59:59.000Z

    In order to examine phantom length necessary to assess radiation dose delivered to patients in cone-beam CT with an enlarged beamwidth, we measured dose profiles in cylindrical phantoms of sufficient length using a prototype 256-slice CT-scanner developed at our institute. Dose profiles parallel to the rotation axis were measured at the central and peripheral positions in PMMA (polymethylmethacrylate) phantoms of 160 or 320 mm diameter and 900 mm length. For practical application, we joined unit cylinders (150 mm long) together to provide phantoms of 900 mm length. Dose profiles were measured with a pin photodiode sensor having a sensitive region of approximately 2.8x2.8 mm{sup 2} and 2.7 mm thickness. Beamwidths of the scanner were varied from 20 to 138 mm. Dose profile integrals (DPI) were calculated using the measured dose profiles for various beamwidths and integration ranges. For the body phantom (320-mm-diam phantom), 76% of the DPI was represented for a 20 mm beamwidth and 60% was represented for a 138 mm beamwidth if dose profiles were integrated over a 100 mm range, while more than 90% of the DPI was represented for beamwidths between 20 and 138 mm if integration was carried out over a 300 mm range. The phantom length and integration range for dosimetry of cone-beam CT needed to be more than 300 mm to represent more than 90% of the DPI for the body phantom with the beamwidth of more than 20 mm. Although we reached this conclusion using the prototype 256-slice CT-scanner, it may be applied to other multislice CT-scanners as well.

  11. Proton radiation damage in P-channel CCDs fabricated on high-resistivity silicon

    E-Print Network [OSTI]

    2002-01-01T23:59:59.000Z

    Proton Radiation Damage in P-Channel CCDs Fabricated onmeasured as a function of radiation dose. These CCDs werecurrent vs. 1/kT after a radiation dose of 5 × 10 9 protons/

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

    SciTech Connect (OSTI)

    Scott, Bobby, R., Ph.D.

    2003-06-27T23:59:59.000Z

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

  13. The Relationship between Organ Dose and Patients Size in Multidetector Computed Tomography (MDCT) Scans Utilizing Tube Current Modulation (TCM)

    E-Print Network [OSTI]

    Khatonabadi, Maryam

    2013-01-01T23:59:59.000Z

    and radiation dose using Siemens Care Dose 4D. Radiation2 Adj. R 2 Adj. R 2 Predictors WED R 2 Siemens Toshiba PedsKidneys WED Siemens Spleen WED GE Liver WED Interaction WED

  14. Phase I Dose Escalation Trial of Vandetanib With Fractionated Radiosurgery in Patients With Recurrent Malignant Gliomas

    SciTech Connect (OSTI)

    Fields, Emma C. [Department of Radiation Oncology, University of Colorado School of Medicine, Aurora, CO (United States); Damek, Denise [Department of Neurology, University of Colorado School of Medicine, Aurora, CO (United States); Gaspar, Laurie E.; Liu, Arthur K.; Kavanagh, Brian D. [Department of Radiation Oncology, University of Colorado School of Medicine, Aurora, CO (United States); Waziri, Allen; Lillehei, Kevin [Department of Neurosurgery, University of Colorado School of Medicine, Aurora, CO (United States); Chen, Changhu, E-mail: changhu.chen@ucdenver.edu [Department of Radiation Oncology, University of Colorado School of Medicine, Aurora, CO (United States)

    2012-01-01T23:59:59.000Z

    Purpose: To determine the maximum tolerated dose (MTD) of vandetanib with fractionated stereotactic radiosurgery (SRS) in patients with recurrent malignant gliomas. Methods and Materials: Patients with a recurrent malignant glioma and T1-enhancing recurrent tumor {<=}6 cm were eligible. Vandetanib was given orally, once per day, 7 days a week, starting at least 7 days before SRS and continued until a dose-limiting toxicity (DLT) or disease progression. The planned vandetanib daily dose was 100 mg, 200 mg, and 300 mg for the cohorts 1, 2, and 3, respectively, and was escalated using a standard 3+3 design. A total SRS dose of 36 Gy, 12 Gy per fraction, was delivered over 3 consecutive days. The MTD was defined as the dose of vandetanib at which less than 33% of patients developed DLTs, defined by the Common Terminology Criteria for Adverse Events (CTCAE) version 3 as any Grade 3 or greater nonhematologic toxicity and Grade 4 or greater hematologic toxicity. Results: Ten patients were treated, 6 on cohort 1 and 4 on cohort 2. Treatment characteristics were: 7 men, 3 women; median age, 40 years (range, 22-72); 7 GBM, 3 anaplastic astrocytoma (AA); median initial radiation (RT) dose, 60 Gy (range, 59.4-70); median interval since initial RT, 14.5 months (range, 7-123); All patients received SRS per protocol. The median follow-up time was 4 months (range, 1-10 months). Median time on vandetanib was 3 months (range 1-11). One of 6 patients in the first cohort developed a DLT of Grade 3 hemothorax while on anticoagulation. The MTD was reached when 2 of the 4 patients enrolled in the second cohort developed DLTs. Six patients had radiographic response, 2 with stable disease. Conclusion: The MTD of vandetanib, with SRS in recurrent malignant glioma, is 100 mg daily. Further evaluation of safety and efficacy is warranted.

  15. ORISE Video: What is radiation dose?

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What's Possible for Renewable Energy:Nanowire3627 FederalTransformers1 DIRECTORJoe Lake One-Timemeasuring

  16. Radiation delivery system and method

    DOE Patents [OSTI]

    Sorensen, Scott A. (Overland Park, KS); Robison, Thomas W. (Los Alamos, NM); Taylor, Craig M. V. (Jemez Springs, NM)

    2002-01-01T23:59:59.000Z

    A radiation delivery system and method are described. The system includes a treatment configuration such as a stent, balloon catheter, wire, ribbon, or the like, a portion of which is covered with a gold layer. Chemisorbed to the gold layer is a radiation-emitting self-assembled monolayer or a radiation-emitting polymer. The radiation delivery system is compatible with medical catheter-based technologies to provide a therapeutic dose of radiation to a lesion following an angioplasty procedure.

  17. Hanford Environmental Dose Reconstruction Project monthly report, February 1993

    SciTech Connect (OSTI)

    Cannon, S.D.; Finch, S.M. (comps.)

    1993-01-01T23:59:59.000Z

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

  18. Hanford Environmental Dose Reconstruction Project monthly report, February 1993

    SciTech Connect (OSTI)

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

    1993-03-01T23:59:59.000Z

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

  19. Hanford Environmental Dose Reconstruction Project. Monthly report, November 1991

    SciTech Connect (OSTI)

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

    1991-12-31T23:59:59.000Z

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

  20. Hanford Environmental Dose Reconstruction Project monthly report, May 1992

    SciTech Connect (OSTI)

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

    1992-08-01T23:59:59.000Z

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

  1. Hanford Environmental Dose Reconstruction Project monthly report, May 1992

    SciTech Connect (OSTI)

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

    1992-01-01T23:59:59.000Z

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

  2. Radiation Damage of Polypropylene Fiber Targets in Storage Rings

    E-Print Network [OSTI]

    H. Rohdjess; D. Albers; J. Bisplinghoff; R. Bollmann; K. Buesser; O. Diehl; F. Dohrmann; H. -P. Engelhardt; P. D. Eversheim; J. Greiff; A. Gross; R. Gross-Hardt; F. Hinterberger; M. Igelbrink; R. Langkau; R. Maier; F. Mosel; M. Mueller; M. Muenstermann; D. Prasuhn; P. von Rossen; H. Scheid; N. Schirm; F. Schwandt; W. Scobel; H. J. Trelle; A. Wellinghausen; W. Wiedmann; K. Woller; R. Ziegler

    2004-03-23T23:59:59.000Z

    Thin polypropylene (CH$_2$) fibers have been used for internal experiments in storage rings as an option for hydrogen targets. The change of the hydrogen content due to the radiation dose applied by the circulating proton beam has been investigated in the range $1\\cdot10^6$ to $2\\cdot10^8$~Gy at beam momenta of 1.5 to 3 GeV/c by comparing the elastic pp-scattering yield to that from inelastic p-carbon reactions. It is found that the loss of hydrogen as a function of applied dose receives contributions from a fast and a slow component.

  3. Radiation physics, biophysics, and radiation biology

    SciTech Connect (OSTI)

    Hall, E.J.

    1992-05-01T23:59:59.000Z

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

  4. Hanford Environmental Dose Reconstruction Project. Monthly report

    SciTech Connect (OSTI)

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

    1992-07-01T23:59:59.000Z

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

  5. Radiosensitizing activity and pharmacokinetics of multiple dose administered KU-2285 in peripheral nerve tissue in mice

    SciTech Connect (OSTI)

    Iwai, Hiroyuki; Matsuno, Etsuko (Daikin Industries, Ltd., Settsu (Japan)); Sasai, Keisuke; Abe, Mitsuyuki; Shibamoto, Yuta (Kyoto Univ. (Japan))

    1994-06-15T23:59:59.000Z

    In a clinical trial in which a 2-nitroimidazole radiosensitizer was administered repeatedly, the dose-limiting toxicity was found to be peripheral neuropathy. In the present study, the in vivo radiosensitizing activity of KU-2285 in combination with radiation dose fractionation, and the pharmacokinetics of cumulative dosing of KU-2285 in the peripheral nerves were examined. The ability of three nitroimidazoles, misonidazole (MISO), etanidazole (SR-2508) and KU-2285, to sensitize SCCVII tumors to radiation treatment has been compared for drug doses in the range 0-200 mg/kg. Single radiation doses or two different fractionation schedules (6 Gy/fractions [times] three fractions/48 h or 5 Gy/fractions [times] five fractions/48 h) were used; the tumor cell survival was determined using an in vivo/in vitro colony assay. The pharmacokinetics in the sciatic nerves were undertaken, when KU-2285 or etanidazole were injected at a dose of 200 mg/kg intravenously one, two, three, or four times at 2-h intervals. At less than 100 mg/kg, KU-2285 sensitized SCCVII tumors more than MISO and SR-2508 by fractionated irradiation. Evaluation of pharmacokinetics in the peripheral nerves showed that the apparent biological half-life of SR-2508 increased with the increases in the number of administrations, whereas that of KU-2285 became shorter. Since most clinical radiotherapy is given in small multiple fractions, KU-2285 appears to be a hypoxic cell radiosensitizer that could be useful in such regimens, and that poses no risk of chronic peripheral neurotoxicity. 12 refs., 5 figs., 1 tab.

  6. Measurement of Radiation Damage on Silica Aerogel Cerenkov Radiator

    E-Print Network [OSTI]

    Belle Preprint; Sahu Wang; M. Z. Wang; R. Suda; R. Enomoto; K. C. Peng; C. H. Wang; I. Adachi; M. Amami

    We measured the radiation damage on silica aerogel Cerenkov radiators originally developed for the B-factory experiment at KEK. Refractive index of the aerogel samples ranged from 1.012 to 1.028. The samples were irradiated up to 9.8 MRad of equivalent dose. Measurements of transmittance and refractive index were carried out and these samples were found to be radiation hard. Deteriorations in transparency and changes of refractive index were observed to be less than 1.3% and 0.001 at 90% confidence level, respectively. Prospects of using aerogels under high-radiation environment are discussed. 1 Introduction Silica aerogels(aerogels) are a colloidal form of glass, in which globules of silica are connected in three dimensional networks with siloxan bonds. They are solid, very light, transparent and their refractive index can be controlled in the production process. Many high energy and nuclear physics experiments have used aerogels instead of pressurized gas for their Cerenkov coun...

  7. Determination of radionuclides and pathways contributing to cumulative dose. Hanford Environmental Dose Reconstruction Project: Dose code recovery activities, Calculation 004

    SciTech Connect (OSTI)

    Napier, B.A.

    1992-12-01T23:59:59.000Z

    A series of scoping calculations has been undertaken to evaluate the absolute and relative contributions of different radionuclides and exposure pathways to doses that may have been received by individuals living in the vicinity of the Hanford Site. This scoping calculation (Calculation 004) examined the contributions of numerous radionuclides to cumulative dose via environmental exposures and accumulation in foods. Addressed in this calculation were the contributions to organ and effective dose of infants and adults from (1) air submersion and groundshine external dose, (2) inhalation, (3) ingestion of soil by humans, (4) ingestion of leafy vegetables, (5) ingestion of other vegetables and fruits, (6) ingestion of meat, (7) ingestion of eggs, and (8) ingestion of cows` milk from Feeding Regime 1, as described in calculation 002. This calculation specifically addresses cumulative radiation doses to infants and adults resulting from releases occurring over the period 1945 through 1972.

  8. Multicriteria optimization of the spatial dose distribution

    SciTech Connect (OSTI)

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

    2013-12-15T23:59:59.000Z

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

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

    SciTech Connect (OSTI)

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

    1985-01-01T23:59:59.000Z

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

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

    SciTech Connect (OSTI)

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

    1987-04-01T23:59:59.000Z

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

  11. Draft Air Pathway Report: Phase 1 of the Hanford Environmental Dose Reconstruction Project

    SciTech Connect (OSTI)

    Not Available

    1990-07-20T23:59:59.000Z

    This report summarizes the air pathway portion of the first phase of the Hanford Environmental Dose Reconstruction (HEDR) Project, conducted by Battelle staff at the Pacific Northwest Laboratory under the direction of an independent Technical Steering Panel. The HEDR Project is estimating historical radiation doses that could have been received by populations near the Department of Energy's Hanford Site, in southeastern Washington State. Phase 1 of the air-pathway dose reconstruction sought to determine whether dose estimates could be calculated for populations in the 10 counties nearest the Hanford Site from atmospheric releases of iodine-131 from the site from 1944--1947. Phase 1 demonstrated the following: HEDR-calculated source-term estimates of iodine-131 releases to the atmosphere were within 20% of previously published estimates; calculated vegetation concentrations of iodine-131 agree well with previously published measurements; the highest of the Phase 1 preliminary dose estimates to the thyroid are consistent with independent, previously published estimates of doses to maximally exposed individuals; and relatively crude, previously published measurements of thyroid burdens for Hanford workers are in the range of average burdens that the HEDR model estimated for similar reference individuals'' for the period 1944--1947. 4 refs., 10 figs., 9 tabs.

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

    SciTech Connect (OSTI)

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

    2012-01-01T23:59:59.000Z

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

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

    SciTech Connect (OSTI)

    Engelward, Bevin P

    2009-09-16T23:59:59.000Z

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

  14. Hanford Environmental Dose Reconstruction Project Monthly Report

    SciTech Connect (OSTI)

    Finch, S.M. (comp.)

    1990-05-01T23:59:59.000Z

    This monthly report summarizes the technical progress and project status for the Hanford Environmental Dose Reconstruction (HEDR) Project being conducted at Pacific Northwest Laboratory (PNL) under the direction of a Technical Steering Panel (TSP). The TSP is composed of experts in numerous technical fields related to this project and represents the interests of the public. The US Department of Energy (DOE) funds the project. The objective of the Hanford Environmental Dose Reconstruction Project is to estimate the radiation doses that populations could have received from nuclear operations at Hanford since 1944. The project is divided into the following technical tasks. These tasks address each of the primary steps in the path from radioactive releases to dose estimates source terms, environmental transport, environmental monitoring data, demographics, agriculture, and food habits, and environmental pathways and dose estimates.

  15. Report to the DOE nuclear data committee. [EV RANGE 10-100; CROSS SECTIONS; PHOTONEUTRONS; NEUTRONS; GAMMA RADIATION; COUPLED CHANNEL THEORY; DIFFERENTIAL CROSS SECTIONS; MEV RANGE 01-10; ; CAPTURE; GAMMA SPECTRA; THERMAL NEUTRONS; COMPUTER CALCULATIONS; DECAY; FISSION PRODUCTS; FISSION YIELD; SHELL MODELS; NUCLEAR DATA COLLECTIONS

    SciTech Connect (OSTI)

    Struble, G.L.; Haight, R.C.

    1981-03-01T23:59:59.000Z

    Topics covered include: studies of (n, charged particle) reactions with 14 to 15 MeV neutrons; photoneutron cross sections for /sup 15/N; neutron radiative capture; Lane-model analysis of (p,p) and (n,n) scattering on the even tin isotopes; neutron scattering cross sections for /sup 181/Ta, /sup 197/Au, /sup 209/Bi, /sup 232/Th, and /sup 238/U inferred from proton scattering and charge exchange cross sections; neutron-induced fission cross sections of /sup 245/Cm and /sup 242/Am; fission neutron multiplicities for /sup 245/Cm and /sup 242/Am; the transport of 14 MeV neutrons through heavy materials 150 < A < 208; /sup 249/Cm energy levels from measurement of thermal neutron capture gamma rays; /sup 231/Th energy levels from neutron capture gamma ray and conversion electron spectroscopy; new measurements of conversion electron binding energies in berkelium and californium; nuclear level densities; relative importance of statistical vs. valence neutron capture in the mass-90 region; determination of properties of short-lived fission products; fission yield of /sup 87/Br and /sup 137/I from 15 nuclei ranging from /sup 232/Th to /sup 249/Cf; evaluation of charged particle data for the ECPL library; evaluation of secondary charged-particle energy and angular distributions for ENDL; and evaluated nuclear structure libraries derived from the table of isotopes. (GHT)

  16. Electromagnetic Radiation Hardness of Diamond Detectors

    E-Print Network [OSTI]

    T. Behnke; M. Doucet; N. Ghodbane; A. Imhof; C. Martinez; W. Zeuner

    2001-08-22T23:59:59.000Z

    The behavior of artificially grown CVD diamond films under intense electromagnetic radiation has been studied. The properties of irradiated diamond samples have been investigated using the method of thermally stimulated current and by studying their charge collection properties. Diamonds have been found to remain unaffected after doses of 6.8 MGy of 10 keV photons and 10 MGy of MeV-range photons. This observation makes diamond an attractive detector material for a calorimeter in the very forward region of the proposed TESLA detector.

  17. Radiation physics, biophysics, and radiation biology

    SciTech Connect (OSTI)

    Hall, E.J.; Zaider, M.

    1993-05-01T23:59:59.000Z

    Research at the Center for Radiological Research is a multidisciplenary blend of physics, chemistry and biology aimed at understanding the mechanisms involved in the health problems resulting from human exposure to ionizing radiations. The focus is increased on biochemistry and the application of the techniques of molecular biology to the problems of radiation biology. Research highlights of the program from the past year are described. A mathematical model describing the production of single-strand and double-strand breaks in DNA as a function radiation quality has been completed. For the first time Monte Carlo techniques have been used to obtain directly the spatial distribution of DNA moieties altered by radiation. This information was obtained by including the transport codes a realistic description of the electronic structure of DNA. We have investigated structure activity relationships for the potential oncogenicity of a new generation of bioreductive drugs that function as hypoxic cytotoxins. Experimental and theoretical investigation of the inverse dose rate effect, whereby medium LET radiations actually produce an c effect when the dose is protracted, is now at a point where the basic mechanisms are reasonably understood and the complex interplay between dose, dose rate and radiation quality which is necessary for the effect to be present can now be predicted at least in vitro. In terms of early radiobiological damage, a quantitative link has been established between basic energy deposition and locally multiply damaged sites, the radiochemical precursor of DNA double strand breaks; specifically, the spatial and energy deposition requirements necessary to form LMDs have been evaluated. For the first time, a mechanically understood biological fingerprint'' of high-LET radiation has been established. Specifically measurement of the ratio of inter-to intra-chromosomal aberrations produces a unique signature from alpha-particles or neutrons.

  18. Hanford Environmental Dose Reconstruction Project. Monthly report

    SciTech Connect (OSTI)

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

    1991-09-01T23:59:59.000Z

    The objective of the Hanford Environmental Dose Reconstruction Project is to estimate the radiation dose that individuals and populations could have received from nuclear operations at Hanford since 1944. The project is divided into five technical tasks. These tasks correspond to the path radionuclides followed, from release to impact on humans (i.e., dose estimates). The Source Terms Task develops estimates of radioactive emissions from Hanford facilities since 1944. The Environmental Transport Task reconstructs the movements of radioactive particles from the areas of release to populations. The Environmental Monitoring Data Task assemblies, evaluates and reports historical environmental monitoring data. The Demographics, Agriculture and Food Habits Task develops the data needed to identify the populations that could have been affected by the releases. The Environmental Pathways and Dose Estimates Task used the information derived from the other Tasks to estimate the radiation doses individuals could have received from Hanford radiation. This document lists the progress on this project as of September 1991. 3 figs., 2 tabs.

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

    SciTech Connect (OSTI)

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

    2009-01-01T23:59:59.000Z

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

  20. Stereotactic Body Radiation Therapy in Spinal Metastases

    SciTech Connect (OSTI)

    Ahmed, Kamran A. [Mayo Medical School, College of Medicine, Mayo Clinic, Rochester, MN (United States); Stauder, Michael C.; Miller, Robert C.; Bauer, Heather J. [Department of Radiation Oncology, Mayo Clinic, Rochester, MN (United States); Rose, Peter S. [Department of Orthopedic Surgery, Mayo Clinic, Rochester, MN (United States); Olivier, Kenneth R. [Department of Radiation Oncology, Mayo Clinic, Rochester, MN (United States); Brown, Paul D. [Department of Radiation Oncology, University of Texas M.D. Anderson Cancer Center, Houston, TX (United States); Brinkmann, Debra H. [Department of Radiation Oncology, Mayo Clinic, Rochester, MN (United States); Laack, Nadia N., E-mail: laack.nadia@mayo.edu [Department of Radiation Oncology, Mayo Clinic, Rochester, MN (United States)

    2012-04-01T23:59:59.000Z

    Purpose: Based on reports of safety and efficacy, stereotactic body radiotherapy (SBRT) for treatment of malignant spinal tumors was initiated at our institution. We report prospective results of this population at Mayo Clinic. Materials and Methods: Between April 2008 and December 2010, 85 lesions in 66 patients were treated with SBRT for spinal metastases. Twenty-two lesions (25.8%) were treated for recurrence after prior radiotherapy (RT). The mean age of patients was 56.8 {+-} 13.4 years. Patients were treated to a median dose of 24 Gy (range, 10-40 Gy) in a median of three fractions (range, 1-5). Radiation was delivered with intensity-modulated radiotherapy (IMRT) and prescribed to cover 80% of the planning target volume (PTV) with organs at risk such as the spinal cord taking priority over PTV coverage. Results: Tumor sites included 48, 22, 12, and 3 in the thoracic, lumbar, cervical, and sacral spine, respectively. The mean actuarial survival at 12 months was 52.2%. A total of 7 patients had both local and marginal failure, 1 patient experienced marginal but not local failure, and 1 patient had local failure only. Actuarial local control at 1 year was 83.3% and 91.2% in patients with and without prior RT. The median dose delivered to patients who experienced local/marginal failure was 24 Gy (range, 18-30 Gy) in a median of three fractions (range, 1-5). No cases of Grade 4 toxicity were reported. In 1 of 2 patients experiencing Grade 3 toxicity, SBRT was given after previous radiation. Conclusion: The results indicate SBRT to be an effective measure to achieve local control in spinal metastases. Toxicity of treatment was rare, including those previously irradiated. Our results appear comparable to previous reports analyzing spine SBRT. Further research is needed to determine optimum dose and fractionation to further improve local control and prevent toxicity.

  1. Scintillator Waveguide For Sensing Radiation

    DOE Patents [OSTI]

    Bliss, Mary (West Richland, WA); Craig, Richard A. (West Richland, WA); Reeder; Paul L. (Richland, WA)

    2003-04-22T23:59:59.000Z

    The present invention is an apparatus for detecting ionizing radiation, having: a waveguide having a first end and a second end, the waveguide formed of a scintillator material wherein the therapeutic ionizing radiation isotropically generates scintillation light signals within the waveguide. This apparatus provides a measure of radiation dose. The apparatus may be modified to permit making a measure of location of radiation dose. Specifically, the scintillation material is segmented into a plurality of segments; and a connecting cable for each of the plurality of segments is used for conducting scintillation signals to a scintillation detector.

  2. United States-Russian workshop on the stochastic health effects of radiation

    SciTech Connect (OSTI)

    NONE

    1992-12-31T23:59:59.000Z

    In August 1988, two years after the Chernobyle accident, the United States and the Soviet Union signed an agreement to sponsor a Joint coordinating Committee on Civilian Nuclear Reactor Safety, (JCCCNRS). The Soviet Union agreed to provide some information on late effects of radiation exposures and to attempt to add some new insights into low dose and low dose rate radiation consequences. At that time, it had just been revealed that significant radiation exposures had occurred in the South Ural Mountains, associated with the early years of operation of the MAYAK nuclear complex. The need to be able to better predict the long term consequences of overexposures, such as occurred with the Chernobyl accident, was a major factor in organizing this workshop. We decided to invite a small number of experts from the Soviet Union, who had direct knowledge of the situation. A small group of American experts was invited to help in a discussion of the state of knowledge of continual low level exposure. The experts and expertise included: Aspects of bask theoretical radiobiological models, studies on experimental animals exposed to chronic or fractionated external or internal radiation, studies on populations exposed to chronic intake and continual exposures, workers exposed to low or high continual levels of radiation. The intent was to begin a dialog on the issue of a better understanding of the dose rate effect in humans. No detailed conclusions could be reached at this first interaction between out two countries, but a model was prepared which seems to support a range of what are known as low dose and dose rate effectiveness factors. A beginning of an evaluation of the role of radiation dose rate on leukemia risk was also accomplished.

  3. Potential Offsite Radiological Doses Estimated for the Proposed Divine Strake Experiment, Nevada Test Site

    SciTech Connect (OSTI)

    Ron Warren

    2006-12-01T23:59:59.000Z

    An assessment of the potential radiation dose that residents offsite of the Nevada Test Site (NTS) might receive from the proposed Divine Strake experiment was made to determine compliance with Subpart H of Part 61 of Title 40 of the Code of Federal Regulations, National Emission Standards for Emissions of Radionuclides Other than Radon from Department of Energy Facilities. The Divine Strake experiment, proposed by the Defense Threat Reduction Agency, consists of a detonation of 700 tons of heavy ammonium nitrate fuel oil-emulsion above the U16b Tunnel complex in Area 16 of the NTS. Both natural radionuclides suspended, and historic fallout radionuclides resuspended from the detonation, have potential to be transported outside the NTS boundary by wind. They may, therefore, contribute radiological dose to the public. Subpart H states ''Emissions of radionuclides to the ambient air from Department of Energy facilities shall not exceed those amounts that would cause any member of the public to receive in any year an effective dose equivalent of 10 mrem/yr'' (Title 40 of the Code of Federal Regulations [CFR] 61.92) where mrem/yr is millirem per year. Furthermore, application for U.S. Environmental Protection Agency (EPA) approval of construction of a new source or modification of an existing source is required if the effective dose equivalent, caused by all emissions from the new construction or modification, is greater than or equal to 0.1 mrem/yr (40 CFR 61.96). In accordance with Section 61.93, a dose assessment was conducted with the computer model CAP88-PC, Version 3.0. In addition to this model, a dose assessment was also conducted by the National Atmospheric Release Advisory Center (NARAC) at the Lawrence Livermore National Laboratory. This modeling was conducted to obtain dose estimates from a model designed for acute releases and which addresses terrain effects and uses meteorology from multiple locations. Potential radiation dose to a hypothetical maximally exposed individual at the closest NTS boundary to the proposed Divine Strake experiment, as estimated by the CAP88-PC model, was 0.005 mrem with wind blowing directly towards that location. Boundary dose, as modeled by NARAC, ranged from about 0.006 to 0.007 mrem. Potential doses to actual offsite populated locations were generally two to five times lower still, or about 40 to 100 times lower then the 0.1 mrem level at which EPA approval is required pursuant to Section 61.96.

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

    SciTech Connect (OSTI)

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

    2008-08-07T23:59:59.000Z

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

  5. DOE/OR-1066R5/02-03 6-1 6. DOSE CALCULATIONS

    E-Print Network [OSTI]

    Pennycook, Steve

    receive external radiation doses through direct external irradiation by radiations emanating from mechanisms that apply to emissions from ORR. Sections 6.3 and 6.4 discuss the environmental transport, food

  6. New Easy-to-Use Medical Field Guide for Radiation Emergencies...

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

    radiation dose Delayed effects of radiation exposure, and Psychological considerations "Health care providers are expected to treat patients injured in a multitude of possible...

  7. Dosimetric Analysis of Radiation-induced Gastric Bleeding

    SciTech Connect (OSTI)

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

    2012-09-01T23:59:59.000Z

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

  8. Measurement and comparison of individual external doses of high-school students living in Japan, France, Poland and Belarus -- the "D-shuttle" project --

    E-Print Network [OSTI]

    Adachi, N; Adjovi, Y; Aida, K; Akamatsu, H; Akiyama, S; Akli, A; Ando, A; Andrault, T; Antonietti, H; Anzai, S; Arkoun, G; Avenoso, C; Ayrault, D; Banasiewicz, M; Bana?kiewicz, M; Bernandini, L; Bernard, E; Berthet, E; Blanchard, M; Boreyko, D; Boros, K; Charron, S; Cornette, P; Czerkas, K; Dameron, M; Date, I; De Pontbriand, M; Demangeau, F; Dobaczewski, ?; Dobrzy?ski, L; Ducouret, A; Dziedzic, M; Ecalle, A; Edon, V; Endo, K; Endo, T; Endo, Y; Etryk, D; Fabiszewska, M; Fang, S; Fauchier, D; Felici, F; Fujiwara, Y; Gardais, C; Gaul, W; Guérin, L; Hakoda, R; Hamamatsu, I; Handa, K; Haneda, H; Hara, T; Hashimoto, M; Hashimoto, T; Hashimoto, K; Hata, D; Hattori, M; Hayano, R; Hayashi, R; Higasi, H; Hiruta, M; Honda, A; Horikawa, Y; Horiuchi, H; Hozumi, Y; Ide, M; Ihara, S; Ikoma, T; Inohara, Y; Itazu, M; Ito, A; Janvrin, J; Jout, I; Kanda, H; Kanemori, G; Kanno, M; Kanomata, N; Kato, T; Kato, S; Katsu, J; Kawasaki, Y; Kikuchi, K; Kilian, P; Kimura, N; Kiya, M; Klepuszewski, M; Kluchnikov, E; Kodama, Y; Kokubun, R; Konishi, F; Konno, A; Kontsevoy, V; Koori, A; Koutaka, A; Kowol, A; Koyama, Y; Kozio?, M; Kozue, M; Kravtchenko, O; Krucza?a, W; Kud?a, M; Kudo, H; Kumagai, R; Kurogome, K; Kurosu, A; Kuse, M; Lacombe, A; Lefaillet, E; Magara, M; Malinowska, J; Malinowski, M; Maroselli, V; Masui, Y; Matsukawa, K; Matsuya, K; Matusik, B; Maulny, M; Mazur, P; Miyake, C; Miyamoto, Y; Miyata, K; Miyata, K; Miyazaki, M; Mol?da, M; Morioka, T; Morita, E; Muto, K; Nadamoto, H; Nadzikiewicz, M; Nagashima, K; Nakade, M; Nakayama, C; Nakazawa, H; Nihei, Y; Nikul, R; Niwa, S; Niwa, O; Nogi, M; Nomura, K; Ogata, D; Ohguchi, H; Ohno, J; Okabe, M; Okada, M; Okada, Y; Omi, N; Onodera, H; Onodera, K; Ooki, S; Oonishi, K; Oonuma, H; Ooshima, H; Oouchi, H; Orsucci, M; Paoli, M; Penaud, M; Perdrisot, C; Petit, M; Piskowski, A; P?ocharski, A; Polis, A; Polti, L; Potsepnia, T; Przybylski, D; Pytel, M; Quillet, W; Remy, A; Robert, C; Sadowski, M; Saito, M; Sakuma, D; Sano, K; Sasaki, Y; Sato, N; Schneider, T; Schneider, C; Schwartzman, K; Selivanov, E; Sezaki, M; Shiroishi, K; Shustava, I; ?nieci?ska, A; Stalchenko, E; Staro?, A; Stromboni, M; Studzi?ska, W; Sugisaki, H; Sukegawa, T; Sumida, M; Suzuki, Y; Suzuki, K; Suzuki, R; Suzuki, H; Suzuki, K; ?widerski, W; Szudejko, M; Szymaszek, M; Tada, J; Taguchi, H; Takahashi, K; Tanaka, D; Tanaka, G; Tanaka, S; Tanino, K; Tazbir, K; Tcesnokova, N; Tgawa, N; Toda, N; Tsuchiya, H; Tsukamoto, H; Tsushima, T; Tsutsumi, K; Umemura, H; Uno, M; Usui, A; Utsumi, H; Vaucelle, M; Wada, Y; Watanabe, K; Watanabe, S; Watase, K; Witkowski, M; Yamaki, T; Yamamoto, J; Yamamoto, T; Yamashita, M; Yanai, M; Yasuda, K; Yoshida, Y; Yoshida, A; Yoshimura, K; ?mijewska, M; Zuclarelli, E

    2015-01-01T23:59:59.000Z

    Twelve high schools in Japan (of which six are in Fukushima Prefecture), four in France, eight in Poland and two in Belarus cooperated in the measurement and comparison of individual external doses in 2014. In total 216 high-school students and teachers participated in the study. Each participant wore an electronic personal dosimeter "D-shuttle" for two weeks, and kept a journal of his/her whereabouts and activities. The distributions of annual external doses estimated for each region overlap with each other, demonstrating that the personal external individual doses in locations where residence is currently allowed in Fukushima Prefecture and in Belarus are well within the range of estimated annual doses due to the background radiation level of other regions/countries.

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

    SciTech Connect (OSTI)

    Campbell, Phillip Montgomery; Wix, Steven D.

    2013-05-01T23:59:59.000Z

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

  10. Tolerance doses for treatment planning

    SciTech Connect (OSTI)

    Lyman, J.T.

    1985-10-01T23:59:59.000Z

    Data for the tolerance of normal tissues or organs to (low-LET) radiation has been compiled from a number of sources which are referenced at the end of this document. This tolerance dose data are ostensibly for uniform irradiation of all or part of an organ, and are for either 5% (TD/sub 5/) or 50% (TD/sub 50/) complication probability. The ''size'' of the irradiated organ is variously stated in terms of the absolute volume or the fraction of the organ volume irradiated, or the area or the length of the treatment field. The accuracy of these data is questionable. Much of the data represents doses that one or several experienced therapists have estimated could be safely given rather than quantitative analyses of clinical observations. Because these data have been obtained from multiple sources with possible different criteria for the definition of a complication, there are sometimes different values for what is apparently the same endpoint. The data from some sources shows a tendancy to be quantized in 5 Gy increments. This reflects the size of possible round off errors. It is believed that all these data have been accumulated without the benefit of 3-D dose distributions and therefore the estimates of the size of the volume and/or the uniformity of the irradiation may be less accurate than is now possible. 19 refs., 4 figs.

  11. High dose rate intraluminal irradiation in recurrent endobronchial carcinoma

    SciTech Connect (OSTI)

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

    1985-12-01T23:59:59.000Z

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

  12. Occupational dose estimates for a monitored retrievable storage facility

    SciTech Connect (OSTI)

    Harty, R.; Stoetzel, G.A.

    1986-06-01T23:59:59.000Z

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

  13. There Is No Correlation Between Erectile Dysfunction and Dose to Penile Bulb and Neurovascular Bundles Following Real-Time Low-Dose-Rate Prostate Brachytherapy

    SciTech Connect (OSTI)

    Solan, Amy N. [Department of Radiation Oncology, Mount Sinai School of Medicine, New York, NY (United States)], E-mail: amy.solan@mountsinai.org; Cesaretti, Jamie A. [Department of Radiation Oncology, Mount Sinai School of Medicine, New York, NY (United States); Stone, Nelson N. [Department of Urology, Mount Sinai School of Medicine, New York, NY (United States); Stock, Richard G. [Department of Radiation Oncology, Mount Sinai School of Medicine, New York, NY (United States)

    2009-04-01T23:59:59.000Z

    Purpose: We evaluated the relationship between the onset of erectile dysfunction and dose to the penile bulb and neurovascular bundles (NVBs) after real-time ultrasound-guided prostate brachytherapy. Methods and Materials: One hundred forty-seven patients who underwent prostate brachytherapy met the following eligibility criteria: (1) treatment with {sup 125}I brachytherapy to a prescribed dose of 160 Gy with or without hormones without supplemental external beam radiation therapy, (2) identification as potent before the time of implantation based on a score of 2 or higher on the physician-assigned Mount Sinai Erectile Function Score and a score of 16 or higher on the abbreviated International Index of Erectile Function patient assessment, and (3) minimum follow-up of 12 months. Median follow-up was 25.7 months (range, 12-47 months). Results: The 3-year actuarial rate of impotence was 23% (34 of 147 patients). An additional 43% of potent patients (49 of 113 patients) were using a potency aid at last follow-up. The penile bulb volume receiving 100% of the prescription dose (V{sub 100}) ranged from 0-0.05 cc (median, 0 cc), with a dose to the hottest 5% (D{sub 5}) range of 12.5-97.9 Gy (median, 40.8 Gy). There was no correlation between penile bulb D{sub 5} or V{sub 100} and postimplantation impotency on actuarial analysis. For the combined right and left NVB structures, V{sub 100} range was 0.3-5.1 cc (median, 1.8 cc), and V{sub 150} range was 0-1.5 cc (median, 0.31 cc). There was no association between NVB V{sub 100} or V{sub 150} and postimplantation impotency on actuarial analysis. Conclusion: Penile bulb doses are low after real-time ultrasound-guided prostate brachytherapy. We found no correlation between dose to either the penile bulb or NVBs and the development of postimplantation impotency.

  14. What is the probability that radiation caused a particular cancer

    SciTech Connect (OSTI)

    Voelz, G.L.

    1983-01-01T23:59:59.000Z

    Courts, lawyers, health physicists, physicians, and others are searching for a credible answer to the question posed in the title of this paper. The cases in which the question arises frequently stem from an individual that has cancer and they, or their next-of-kin, are convinced that a past radiation exposure - usually small - is responsible for causing it. An arithmetic expression of this problem is simple: the probability of causation by the radiation dose in question is equal to the risk of cancer from the radiation dose divided by the risk of cancer from all causes. The application of risk factors to this equation is not so simple. It must involve careful evaluation of the reliability of and variations in risk coefficients for development of cancer due to radiation exposure, other carcinogenic agents, and natural causes for the particular individual. Examination of our knowledge of these various factors indicates that a large range in the answers can result due to the variability and imprecision of the data. Nevertheless, the attempts to calculate and the probability that radiation caused the cancer is extremely useful to provide a gross perspective on the probability of causation. It will likely rule in or out a significant number of cases despite the limitations in our understandings of the etiology of cancer and the risks from various factors. For the remaining cases, a thoughtful and educated judgment based on selected data and circumstances of the case will also be needed before the expert can develop and support his opinion.

  15. Neutron dose equivalent meter

    DOE Patents [OSTI]

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

    1996-01-01T23:59:59.000Z

    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.

  16. DRY TRANSFER FACILITY WORKER DOSE ASSESSMENT

    SciTech Connect (OSTI)

    J.S. Tang

    2004-09-23T23:59:59.000Z

    The purpose of this calculation is to estimate radiation doses received by personnel working in the Dry Transfer Facility No.1 (DTF-1) performing operations to receive transportation casks, transfer wastes, prepare waste packages, and ship out loaded waste packages and empty casks. Doses received by workers due to maintenance operations are also included in this revision. The specific scope of work contained in this calculation covers both collective doses and individual worker group doses on an annual basis, and includes the contributions due to external and internal radiation from normal operation, excluding the remediation area of the building. The results of this calculation will be used to support the design of the DTF-1 and to provide occupational dose estimates for the License Application. The calculations contained in this document were developed by Environmental and Nuclear Engineering of the Design and Engineering Organization and are intended solely for the use of the Design and Engineering Organization in its work regarding facility operation. Yucca Mountain Project personnel from the Environmental and Nuclear Engineering should be consulted before use of the calculations for purposes other than those stated herein or use by individuals other than authorized personnel in the Environmental and Nuclear Engineering.

  17. Misonidazole with dexamethasone rescue: an escalating dose toxicity study

    SciTech Connect (OSTI)

    Tanasichuk, H.; Urtasun, R.C.; Fulton, D.S.; Raleigh, J.

    1984-09-01T23:59:59.000Z

    Neurotoxicity induced by misonidazole (MISO) and desmethylmisonidazole (DMM) has become the dose limiting factor in clinical work. In 1981, the authors reported a preliminary study suggestive that Dexamethasone (DEXA) does have a protective effect against peripheral neuropathies (PN) resulting from toxicity of misonidazole. The authors are presently investigating the use of DEXA, with escalating doses of MISO in an attempt to modify its neurotoxicity. To date, 16 patients have been registered to receive total doses of MISO given in 9 equally divided doses over 3 weeks. DEXA is given 3 days prior to the first dose and continues for the duration of therapy. All patients receive palliative radiation. No toxicity was seen at the total dose of 13.5 gm/M/sub 2/. One grade I PN occurred in the first four patients receiving 15.5 gm/M/sub 2/. Six additional patients were entered at this dose level and no further incidence of PN was observed.

  18. Impact of dose size in single fraction spatially fractionated (grid) radiotherapy for melanoma

    SciTech Connect (OSTI)

    Zhang, Hualin, E-mail: hualin.zhang@northwestern.edu, E-mail: hualinzhang@yahoo.com [Department of Radiation Oncology, Northwestern University Feinberg School of Medicine, Chicago, Illinois 60611 and Department of Radiation Oncology, Indiana University School of Medicine, Indianapolis, Indiana 46202 (United States)] [Department of Radiation Oncology, Northwestern University Feinberg School of Medicine, Chicago, Illinois 60611 and Department of Radiation Oncology, Indiana University School of Medicine, Indianapolis, Indiana 46202 (United States); Zhong, Hualiang [Department of Radiation Oncology, Henry Ford Health System, Detroit, Michigan 48202 (United States)] [Department of Radiation Oncology, Henry Ford Health System, Detroit, Michigan 48202 (United States); Barth, Rolf F. [Department of Pathology, The Ohio State University, Columbus, Ohio 43210 (United States)] [Department of Pathology, The Ohio State University, Columbus, Ohio 43210 (United States); Cao, Minsong; Das, Indra J. [Department of Radiation Oncology, Indiana University School of Medicine, Indianapolis, Indiana 46202 (United States)] [Department of Radiation Oncology, Indiana University School of Medicine, Indianapolis, Indiana 46202 (United States)

    2014-02-15T23:59:59.000Z

    Purpose: To evaluate the impact of dose size in single fraction, spatially fractionated (grid) radiotherapy for selectively killing infiltrated melanoma cancer cells of different tumor sizes, using different radiobiological models. Methods: A Monte Carlo technique was employed to calculate the 3D dose distribution of a commercially available megavoltage grid collimator in a 6 MV beam. The linear-quadratic (LQ) and modified linear quadratic (MLQ) models were used separately to evaluate the therapeutic outcome of a series of single fraction regimens that employed grid therapy to treat both acute and late responding melanomas of varying sizes. The dose prescription point was at the center of the tumor volume. Dose sizes ranging from 1 to 30 Gy at 100% dose line were modeled. Tumors were either touching the skin surface or having their centers at a depth of 3 cm. The equivalent uniform dose (EUD) to the melanoma cells and the therapeutic ratio (TR) were defined by comparing grid therapy with the traditional open debulking field. The clinical outcomes from recent reports were used to verify the authors’ model. Results: Dose profiles at different depths and 3D dose distributions in a series of 3D melanomas treated with grid therapy were obtained. The EUDs and TRs for all sizes of 3D tumors involved at different doses were derived through the LQ and MLQ models, and a practical equation was derived. The EUD was only one fifth of the prescribed dose. The TR was dependent on the prescribed dose and on the LQ parameters of both the interspersed cancer and normal tissue cells. The results from the LQ model were consistent with those of the MLQ model. At 20 Gy, the EUD and TR by the LQ model were 2.8% higher and 1% lower than by the MLQ, while at 10 Gy, the EUD and TR as defined by the LQ model were only 1.4% higher and 0.8% lower, respectively. The dose volume histograms of grid therapy for a 10 cm tumor showed different dosimetric characteristics from those of conventional radiotherapy. A significant portion of the tumor volume received a very large dose in grid therapy, which ensures significant tumor cell killing in these regions. Conversely, some areas received a relatively small dose, thereby sparing interspersed normal cells and increasing radiation tolerance. The radiobiology modeling results indicated that grid therapy could be useful for treating acutely responding melanomas infiltrating radiosensitive normal tissues. The theoretical model predictions were supported by the clinical outcomes. Conclusions: Grid therapy functions by selectively killing infiltrating tumor cells and concomitantly sparing interspersed normal cells. The TR depends on the radiosensitivity of the cell population, dose, tumor size, and location. Because the volumes of very high dose regions are small, the LQ model can be used safely to predict the clinical outcomes of grid therapy. When treating melanomas with a dose of 15 Gy or higher, single fraction grid therapy is clearly advantageous for sparing interspersed normal cells. The existence of a threshold fraction dose, which was found in the authors’ theoretical simulations, was confirmed by clinical observations.

  19. Comparison of radiation exposure and associated radiation-induced cancer risks from mammography and molecular imaging of the breast

    SciTech Connect (OSTI)

    O'Connor, Michael K.; Li Hua; Rhodes, Deborah J.; Hruska, Carrie B.; Clancy, Conor B.; Vetter, Richard J. [Department of Radiology, Mayo Clinic, Rochester, Minnesota 55905 (United States); Department of Medicine, Mayo Clinic, Rochester, Minnesota 55905 (United States); Department of Radiology, Mayo Clinic, Rochester, Minnesota 55905 (United States); Department of Medical Physics, St. James's Hospital, Dublin (Ireland); Radiation Safety, Mayo Clinic, Rochester, Minnesota 55905 (United States)

    2010-12-15T23:59:59.000Z

    Purpose: Recent studies have raised concerns about exposure to low-dose ionizing radiation from medical imaging procedures. Little has been published regarding the relative exposure and risks associated with breast imaging techniques such as breast specific gamma imaging (BSGI), molecular breast imaging (MBI), or positron emission mammography (PEM). The purpose of this article was to estimate and compare the risks of radiation-induced cancer from mammography and techniques such as PEM, BSGI, and MBI in a screening environment. Methods: The authors used a common scheme for all estimates of cancer incidence and mortality based on the excess absolute risk model from the BEIR VII report. The lifetime attributable risk model was used to estimate the lifetime risk of radiation-induced breast cancer incidence and mortality. All estimates of cancer incidence and mortality were based on a population of 100 000 females followed from birth to age 80 and adjusted for the fraction that survives to various ages between 0 and 80. Assuming annual screening from ages 40 to 80 and from ages 50 to 80, the cumulative cancer incidence and mortality attributed to digital mammography, screen-film mammography, MBI, BSGI, and PEM was calculated. The corresponding cancer incidence and mortality from natural background radiation was calculated as a useful reference. Assuming a 15%-32% reduction in mortality from screening, the benefit/risk ratio for the different imaging modalities was evaluated. Results: Using conventional doses of 925 MBq Tc-99m sestamibi for MBI and BSGI and 370 MBq F-18 FDG for PEM, the cumulative cancer incidence and mortality were found to be 15-30 times higher than digital mammography. The benefit/risk ratio for annual digital mammography was >50:1 for both the 40-80 and 50-80 screening groups, but dropped to 3:1 for the 40-49 age group. If the primary use of MBI, BSGI, and PEM is in women with dense breast tissue, then the administered doses need to be in the range 75-150 MBq for Tc-99m sestamibi and 35 MBq-70 MBq for F-18 FDG in order to obtain benefit/risk ratios comparable to those of mammography in these age groups. These dose ranges should be achievable with enhancements to current technology while maintaining a reasonable examination time. Conclusions: The results of the dose estimates in this study clearly indicate that if molecular imaging techniques are to be of value in screening for breast cancer, then the administered doses need to be substantially reduced to better match the effective doses of mammography.

  20. Brain necrosis after fractionated radiation therapy: Is the halftime for repair longer than we thought?

    SciTech Connect (OSTI)

    Bender, Edward T. [Department of Human Oncology, University of Wisconsin-Madison, School of Medicine and Public Health, 600 Highland Avenue, Madison, Wisconsin 53792 (United States)

    2012-11-15T23:59:59.000Z

    Purpose: To derive a radiobiological model that enables the estimation of brain necrosis and spinal cord myelopathy rates for a variety of fractionation schemes, and to compare repair effects between brain and spinal cord. Methods: Sigmoidal dose response relationships for brain radiation necrosis and spinal cord myelopathy are derived from clinical data using nonlinear regression. Three different repair models are considered and the repair halftimes are included as regression parameters. Results: For radiation necrosis, a repair halftime of 38.1 (range 6.9-76) h is found with monoexponential repair, while for spinal cord myelopathy, a repair halftime of 4.1 (range 0-8) h is found. The best-fit alpha beta ratio is 0.96 (range 0.24-1.73)Conclusions: A radiobiological model that includes repair corrections can describe the clinical data for a variety of fraction sizes, fractionation schedules, and total doses. Modeling suggests a relatively long repair halftime for brain necrosis. This study suggests that the repair halftime for late radiation effects in the brain may be longer than is currently thought. If confirmed in future studies, this may lead to a re-evaluation of radiation fractionation schedules for some CNS diseases, particularly for those diseases where fractionated stereotactic radiation therapy is used.

  1. SU-E-T-79: Comparison of Doses Received by the Hippocampus in Patients Treated with Single Vs Multiple Isocenter Based Stereotactic Radiation Therapy to the Brain for Multiple Brain Metastases

    SciTech Connect (OSTI)

    Algan, O; Giem, J; Young, J; Ali, I; Ahmad, S; Hossain, S [University of Oklahoma Health Sciences Center, Oklahoma City, OK (United States)

    2014-06-01T23:59:59.000Z

    Purpose: To investigate the doses received by the hippocampus and normal brain tissue during a course of stereotactic radiotherapy utilizing a single isocenter (SI) versus multiple isocenter (MI) in patients with multiple intracranial metastases. Methods: Seven patients imaged with MRI including SPGR sequence and diagnosed with 2–3 brain metastases were included in this retrospective study. Two sets of stereotactic IMRT treatment plans, (MI vs SI), were generated. The hippocampus was contoured on SPGR sequences and doses received by the hippocampus and whole brain were calculated. The prescribed dose was 25Gy in 5 fractions. The two groups were compared using t-test analysis. Results: There were 17 lesions in 7 patients. The median tumor, right hippocampus, left hippocampus and brain volumes were: 3.37cc, 2.56cc, 3.28cc, and 1417cc respectively. In comparing the two treatment plans, there was no difference in the PTV coverage except in the tail of the DVH curve. All tumors had V95 > 99.5%. The only statistically significant parameter was the V100 (72% vs 45%, p=0.002, favoring MI). All other evaluated parameters including the V95 and V98 did not reveal any statistically significant differences. None of the evaluated dosimetric parameters for the hippocampus (V100, V80, V60, V40, V20, V10, D100, D90, D70, D50, D30, D10) revealed any statistically significant differences (all p-values > 0.31) between MI and SI plans. The total brain dose was slightly higher in the SI plans, especially in the lower dose regions, although this difference was not statistically significant. Utilizing brain-sub-PTV volumes did not change these results. Conclusion: The use of SI treatment planning for patients with up to 3 brain metastases produces similar PTV coverage and similar normal tissue doses to the hippocampus and the brain compared to MI plans. SI treatment planning should be considered in patients with multiple brain metastases undergoing stereotactic treatment.

  2. Radiation dosimeters

    DOE Patents [OSTI]

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

    1992-01-01T23:59:59.000Z

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

  3. Hanford Environmental Dose Reconstruction Project. Monthly report, June 1992

    SciTech Connect (OSTI)

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

    1992-06-01T23:59:59.000Z

    The objective of the Hanford Environmental Dose Reconstruction Project is to estimate the radiation doses that individuals and populations could have received from nuclear operations at Hanford since 1944. The project is being managed and conducted by the Battelle Pacific Northwest Laboratories under contract with the Centers for Disease Control. The independent Technical Steering Panel (TSP) provides technical direction. The project is divided into the following technical tasks. These tasks correspond to the path radionuclides followed, from release to impact on humans (dose estimates): source terms; environmental transport; environmental monitoring data; demography, food consumption, and agriculture; environmental pathways and dose estimates.

  4. The image quality of ion computed tomography at clinical imaging dose levels

    SciTech Connect (OSTI)

    Hansen, David C., E-mail: dch@oncology.au.dk [Department of Experimental Clinical Oncology, Aarhus University Hospital, 8000 Aarhus (Denmark); Bassler, Niels [Department of Physics and Astronomy, Aarhus University, 8000 Aarhus (Denmark); Sørensen, Thomas Sangild [Department of Computer Science, Aarhus University, 8000 Aarhus, Denmark and Department of Clinical Medicine, Aarhus University, 8000 Aarhus (Denmark); Seco, Joao [Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School,Boston, Massachusetts 02114 (United States)

    2014-11-01T23:59:59.000Z

    Purpose: Accurately predicting the range of radiotherapy ions in vivo is important for the precise delivery of dose in particle therapy. Range uncertainty is currently the single largest contribution to the dose margins used in planning and leads to a higher dose to normal tissue. The use of ion CT has been proposed as a method to improve the range uncertainty and thereby reduce dose to normal tissue of the patient. A wide variety of ions have been proposed and studied for this purpose, but no studies evaluate the image quality obtained with different ions in a consistent manner. However, imaging doses ion CT is a concern which may limit the obtainable image quality. In addition, the imaging doses reported have not been directly comparable with x-ray CT doses due to the different biological impacts of ion radiation. The purpose of this work is to develop a robust methodology for comparing the image quality of ion CT with respect to particle therapy, taking into account different reconstruction methods and ion species. Methods: A comparison of different ions and energies was made. Ion CT projections were simulated for five different scenarios: Protons at 230 and 330 MeV, helium ions at 230 MeV/u, and carbon ions at 430 MeV/u. Maps of the water equivalent stopping power were reconstructed using a weighted least squares method. The dose was evaluated via a quality factor weighted CT dose index called the CT dose equivalent index (CTDEI). Spatial resolution was measured by the modulation transfer function. This was done by a noise-robust fit to the edge spread function. Second, the image quality as a function of the number of scanning angles was evaluated for protons at 230 MeV. In the resolution study, the CTDEI was fixed to 10 mSv, similar to a typical x-ray CT scan. Finally, scans at a range of CTDEI’s were done, to evaluate dose influence on reconstruction error. Results: All ions yielded accurate stopping power estimates, none of which were statistically different from the ground truth image. Resolution (as defined by the modulation transfer function = 10% point) was the best for the helium ions (18.21 line pairs/cm) and worst for the lower energy protons (9.37 line pairs/cm). The weighted quality factor for the different ions ranged from 1.23 for helium to 2.35 for carbon ions. For the angle study, a sharp increase in absolute error was observed below 45 distinct angles, giving the impression of a threshold, rather than smooth, limit to the number of angles. Conclusions: The method presented for comparing various ion CT modalities is feasible for practical use. While all studied ions would improve upon x-ray CT for particle range estimation, helium appears to give the best results and deserves further study for imaging.

  5. Activity concentrations and dose rates from decorative granite countertops W.J. Llope*

    E-Print Network [OSTI]

    Llope, William J.

    Activity concentrations and dose rates from decorative granite countertops W.J. Llope* Rice 19 April 2011 Keywords: Granite Gamma radiation Dose Human phantom a b s t r a c t The gamma radiation emitted from a variety of commercial decorative granites available for use in U.S. homes has been

  6. Radiation Safety Edward O'Connell

    E-Print Network [OSTI]

    /Bureau of Environmental Radiation Protection (BERP) · Regulatory Compliance ­ State Sanitary 16 · Required Radiation to cause ionization depends on the energy #12;Radiation Can Cause Ionization #12;Units of Measurements millirem per year. · At 50,000 feet, the dose rate is about 1 millirem per hour. · There are areas

  7. Neurodegeneration and adaptation in response to low-dose photon irradiation

    SciTech Connect (OSTI)

    Limoli, Charles L. [UCI

    2014-10-27T23:59:59.000Z

    Neural stem and precursor cells (i.e. multipotent neural cells) are concentrated in the neurogenic regions of the brain (hippocampal dentate gyrus, subventricular zones), and considerable evidence suggests that these cells are important in mediating the stress response of the CNS after damage from ionizing radiation. The capability of these cells to proliferate, migrate and differentiate (i.e. to undergo neurogenesis) suggests they can participate in the repair and maintenance of CNS functions by replacing brain cells damaged or depleted due to irradiation. Importantly, we have shown that multipotent neural cells are markedly sensitive to irradiation and oxidative stress, insults that compromise neurogenesis and hasten the onset and progression of degenerative processes that are likely to have an adverse impact on cognition. Our past and current work has demonstrated that relatively low doses of radiation cause a persistent (weeks-months) oxidative stress in multipotent neural cells that can elicit a range of degenerative sequelae in the CNS. Therefore, our project is focused on determining the extent that endogenous and redox sensitive multipotent neural cells represent important radioresponsive targets for low dose radiation effects. We hypothesize that the activation of redox sensitive signaling can trigger radioadaptive changes in these cells that can be either harmful or beneficial to overall cognitive health.

  8. Technical Reports Ultra-low Dose Lung CT Perfusion Regularized by

    E-Print Network [OSTI]

    Virginia Tech

    Technical Reports Ultra-low Dose Lung CT Perfusion Regularized by a Previous Scan1 Hengyong Yu, Ph­regularized reconstruction (PSRR) method was proposed to reduce radiation dose and applied to lung perfusion studies. Normal and ultra-low-dose lung computed tomographic perfusion studies were compared in terms of the estimation

  9. Analytic approximate radiation effects due to Bremsstrahlung

    SciTech Connect (OSTI)

    Ben-Zvi I.

    2012-02-01T23:59:59.000Z

    The purpose of this note is to provide analytic approximate expressions that can provide quick estimates of the various effects of the Bremsstrahlung radiation produced relatively low energy electrons, such as the dumping of the beam into the beam stop at the ERL or field emission in superconducting cavities. The purpose of this work is not to replace a dependable calculation or, better yet, a measurement under real conditions, but to provide a quick but approximate estimate for guidance purposes only. These effects include dose to personnel, ozone generation in the air volume exposed to the radiation, hydrogen generation in the beam dump water cooling system and radiation damage to near-by magnets. These expressions can be used for other purposes, but one should note that the electron beam energy range is limited. In these calculations the good range is from about 0.5 MeV to 10 MeV. To help in the application of this note, calculations are presented as a worked out example for the beam dump of the R&D Energy Recovery Linac.

  10. Minibeam radiation therapy for the management of osteosarcomas: A Monte Carlo study

    SciTech Connect (OSTI)

    Martínez-Rovira, I.; Prezado, Y., E-mail: prezado@gmail.com [Laboratoire d’Imagerie et Modélisation en Neurobiologie et Cancérologie (IMNC), Centre National de la Recherche Scientifique (CNRS), Campus universitaire, Bât. 440, 1er étage, 15 rue Georges Clemenceau, 91406 Orsay cedex (France)

    2014-06-15T23:59:59.000Z

    Purpose: Minibeam radiation therapy (MBRT) exploits the well-established tissue-sparing effect provided by the combination of submillimetric field sizes and a spatial fractionation of the dose. The aim of this work is to evaluate the feasibility and potential therapeutic gain of MBRT, in comparison with conventional radiotherapy, for osteosarcoma treatments. Methods: Monte Carlo simulations (PENELOPE/PENEASY code) were used as a method to study the dose distributions resulting from MBRT irradiations of a rat femur and a realistic human femur phantoms. As a figure of merit, peak and valley doses and peak-to-valley dose ratios (PVDR) were assessed. Conversion of absorbed dose to normalized total dose (NTD) was performed in the human case. Several field sizes and irradiation geometries were evaluated. Results: It is feasible to deliver a uniform dose distribution in the target while the healthy tissue benefits from a spatial fractionation of the dose. Very high PVDR values (?20) were achieved in the entrance beam path in the rat case. PVDR values ranged from 2 to 9 in the human phantom. NTD{sub 2.0} of 87 Gy might be reached in the tumor in the human femur while the healthy tissues might receive valley NTD{sub 2.0} lower than 20 Gy. The doses in the tumor and healthy tissues might be significantly higher and lower than the ones commonly delivered used in conventional radiotherapy. Conclusions: The obtained dose distributions indicate that a gain in normal tissue sparing might be expected. This would allow the use of higher (and potentially curative) doses in the tumor. Biological experiments are warranted.

  11. Incidence of Second Malignancies Among Patients Treated With Proton Versus Photon Radiation

    SciTech Connect (OSTI)

    Chung, Christine S., E-mail: chungc1@sutterhealth.org [Department of Radiation Oncology, Alta Bates Summit Medical Center, Berkeley, California (United States); Yock, Torunn I. [Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States); Nelson, Kerrie [Department of Biostatistics, Boston University School of Public Health, Boston, Massachusetts (United States); Xu, Yang [Department of Health Care Policy, Harvard Medical School, Boston, Massachusetts (United States); Keating, Nancy L. [Department of Health Care Policy, Harvard Medical School, Boston, Massachusetts (United States); Department of General Internal Medicine, Brigham and Women's Hospital, Boston, Massachusetts (United States); Tarbell, Nancy J. [Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States); Office of the Executive Dean, Harvard Medical School, Boston, Massachusetts (United States)

    2013-09-01T23:59:59.000Z

    Purpose: Proton radiation, when compared with photon radiation, allows delivery of increased radiation dose to the tumor while decreasing dose to adjacent critical structures. Given the recent expansion of proton facilities in the United States, the long-term sequelae of proton therapy should be carefully assessed. The objective of this study was to compare the incidence of second cancers in patients treated with proton radiation with a population-based cohort of matched patients treated with photon radiation. Methods and Materials: We performed a retrospective cohort study of 558 patients treated with proton radiation from 1973 to 2001 at the Harvard Cyclotron in Cambridge, MA and 558 matched patients treated with photon therapy in the Surveillance, Epidemiology, and End Results (SEER) Program cancer registry. Patients were matched by age at radiation treatment, sex, year of treatment, cancer histology, and site. The main outcome measure was the incidence of second malignancies after radiation. Results: We matched 558 proton patients with 558 photon patients from the Surveillance, Epidemiology, and End Results registry. The median duration of follow-up was 6.7 years (interquartile range, 7.4) and 6.0 years (interquartile range, 9.3) in the proton and photon cohorts, respectively. The median age at treatment was 59 years in each cohort. Second malignancies occurred in 29 proton patients (5.2%) and 42 photon patients (7.5%). After we adjusted for sex, age at treatment, primary site, and year of diagnosis, proton therapy was not associated with an increased risk of second malignancy (adjusted hazard ratio, 0.52 [95% confidence interval, 0.32-0.85]; P=.009). Conclusions: The use of proton radiation therapy was not associated with a significantly increased risk of secondary malignancies compared with photon therapy. Longer follow-up of these patients is needed to determine if there is a significant decrease in second malignancies. Given the limitations of the study, these results should be viewed as hypothesis generating.

  12. SU-E-T-118: Dose Verification for Accuboost Applicators Using TLD, Ion Chamber and Gafchromic Film Measurements

    SciTech Connect (OSTI)

    Chisela, W; Yao, R; Dorbu, G [Columbus Regional Healthcare, Columbus, GA (United States)

    2014-06-01T23:59:59.000Z

    Purpose: To verify dose delivered with HDR Accuboost applicators using TLD, ion chamber and Gafchromic film measurements and to examine applicator leakage. Methods: A microSelectron HDR unit was used to deliver a dose of 50cGy to the mid-plane of a 62mm thick solid water phantom using dwell times from Monte Carlo pre-calculated nomograms for a 60mm, 70mm Round and 60mm Skin-Dose Optimized (SDO) applicators respectively. GafChromic EBT3+ film was embedded in the phantom midplane horizontally to measure dose distribution. Absolute dose was also measured with TLDs and an ADCL calibrated parallel-plate ion chamber placed in the film plane at field center for each applicator. The film was calibrated using 6MV x-ray beam. TLDs were calibrated in a Cs-137 source at UW-Madison calibration laboratory. Radiation leakage through the tungsten alloy shell was measured with a film wrapped around outside surface of a 60mm Round applicator. Results: Measured maximum doses at field center are consistently lower than predicated by 5.8% for TLD, 8.8% for ion chamber, and 2.6% for EBT3+ film on average, with measurement uncertainties of 2.2%, 0.3%, and 2.9% for TLD, chamber, film respectively. The total standard uncertainties for ion chamber and Gafchromic film measurement are 4.9% and 4.6% respectively[1]. The area defined by the applicator aperture was covered by 80% of maximum dose for 62mm compression thickness. When 100cGy is delivered to mid-plane with a 60mm Round applicator, surface dose ranges from 60cGy to a maximum of 145cGy, which occurs at source entrance to the applicator. Conclusion: Measured doses by all three techniques are consistently lower than predicted in our measurements. For a compression thickness of 62 mm, the field size defined by the applicator is only covered by 80% of prescribed dose. Radiation leakage of up to 145cGy was found at the source entrance of applicators.

  13. A phase I trial of stereotactic body radiation therapy (SBRT) for liver metastases

    SciTech Connect (OSTI)

    Schefter, Tracey E. [Department of Radiation Oncology, University of Colorado Health Sciences Center, Aurora, CO (United States)]. E-mail: Tracey.Schefter@uchsc.edu; Kavanagh, Brian D. [Department of Radiation Oncology, University of Colorado Health Sciences Center, Aurora, CO (United States); Timmerman, Robert D. [Department of Radiation Oncology, University of Texas-Southwestern, Dallas, TX (United States); Cardenes, Higinia R. [Department of Radiation Oncology, Indiana University School of Medicine, Indianapolis, IN (United States); Baron, Anna [Department of Biostatics, University of Colorado Comprehensive Cancer Center, Aurora, CO (United States); Gaspar, Laurie E. [Department of Radiation Oncology, University of Colorado Health Sciences Center, Aurora, CO (United States)

    2005-08-01T23:59:59.000Z

    Purpose: To determine the maximum tolerated dose (MTD) of stereotactic body radiation therapy (SBRT) for liver metastases. Methods and Materials: A multicenter Phase I clinical trial was conducted. Eligible patients had one to three liver metastases, tumor diameter <6 cm, and adequate liver function. The first cohort received 36 Gy to the planning target volume (PTV) in three fractions (F). Subsequent cohorts received higher doses up to a chosen maximum of 60 Gy/3F. At least 700 mL of normal liver had to receive a total dose <15 Gy. Dose-limiting toxicity (DLT) included acute Grade 3 liver or intestinal toxicity or any acute Grade 4 toxicity. The MTD was exceeded if 2/6 patients in a cohort experienced DLT. Results: Eighteen patients were enrolled (10 male, 8 female): median age, 55 years (range, 26-83 years); most common primary site, colorectal (6 patients); median aggregate gross tumor volume, 18 ml (range, 3-98 ml). Four patients had multiple tumors. No patient experienced a DLT, and dose was escalated to 60 Gy/3F without reaching MTD. Conclusions: Biologically potent doses of SBRT are well tolerated in patients with limited liver metastases. Results of this study form the basis for an ongoing Phase II SBRT study of 60 Gy over three fractions for liver metastases.

  14. 22.01 Introduction to Ionizing Radiation, Fall 2003

    E-Print Network [OSTI]

    Coderre, Jeffrey A.

    Introduction to basic properties of ionizing radiations and their uses in medicine, industry, science, and environmental studies. Discusses natural and man-made radiation sources, energy deposition and dose calculations, ...

  15. Abdominal radiation causes bacterial translocation

    SciTech Connect (OSTI)

    Guzman-Stein, G.; Bonsack, M.; Liberty, J.; Delaney, J.P.

    1989-02-01T23:59:59.000Z

    The purpose of this study was to determine if a single dose of radiation to the rat abdomen leads to bacterial translocation into the mesenteric lymph nodes (MLN). A second issue addressed was whether translocation correlates with anatomic damage to the mucosa. The radiated group (1100 cGy) which received anesthesia also was compared with a control group and a third group which received anesthesia alone but no abdominal radiation. Abdominal radiation lead to 100% positive cultures of MLN between 12 hr and 4 days postradiation. Bacterial translocation was almost nonexistent in the control and anesthesia group. Signs of inflammation and ulceration of the intestinal mucosa were not seen until Day 3 postradiation. Mucosal damage was maximal by Day 4. Bacterial translocation onto the MLN after a single dose of abdominal radiation was not apparently dependent on anatomical, histologic damage of the mucosa.

  16. Enhanced tumor responses through therapies combining CCNU, MISO and radiation

    SciTech Connect (OSTI)

    Siemann, D.W.; Hill, S.A.

    1984-09-01T23:59:59.000Z

    Studies were performed to determine whether the radiation sensitizer misonidazole (MISO) could enhance the tumor control probability in a treatment strategy combining radiation and the nitrosourea 1-(2-chloroethyl)-3-cyclohexyl-1-nitrosourea (CCNU). In initial experiments KHT sarcoma-bearing mice were injected with 1.0 mg/g of MISO simultaneously with a 20 mg/kg dose of CCNU 30-40 min prior to irradiation (1500 rad). With this treatment protocol approximately 60% of the mice were found to be tumor-free 100 days post treatment. By comparison all 2 agent combinations led to 0% cures. To evaluate the relative importance of chemopotentiation versus radiosensitization in the 3 agent protocol, tumors were treated with MISO plus one anti-tumor agent (either radiation of CCNU) and then at times ranging from 0 to 24 hr later exposed to the other agent. When the time between treatments was 0 to 6 hr, a 60 to 80% tumor control rate was achieved for both MISO plus radiation followed by CCNU and MISO plus CCNU followed by radiation. However if the time interval was increased to 18 or 24 hr, the cure rate in the former treatment regimen dropped to 10% while that of the latter remained high at 40%. The data therefore indicate that (1) improved tumor responses may be achieved when MISO is added to a radiation-chemotherapy combination and (2) MISO may be more effective in such a protocol when utilized as a chemopotentiator.

  17. Phase 1 of the Hanford Environmental Dose Reconstruction Project

    SciTech Connect (OSTI)

    Not Available

    1991-08-01T23:59:59.000Z

    The work described in this report was prompted by the public's concern about potential effect from the radioactive materials released from the Hanford Site. The Hanford Environmental Dose Reconstruction (HEDR) Project was established to estimate radiation dose the public might have received from the Hanford Site since 1944, when facilities began operating. Phase 1 of the HEDR Project is a pilot'' or demonstration'' phase. The objectives of this initial phase were to determine whether enough historical information could be found or reconstructed to be used for dose estimation and develop and test conceptual and computational models for calculating credible dose estimates. Preliminary estimates of radiation doses were produced in Phase 1 because they are needed to achieve these objectives. The reader is cautioned that the dose estimates provided in this and other Phase 1 HEDR reports are preliminary. As the HEDR Project continues, the dose estimates will change for at least three reasons: more complete input information for models will be developed; the models themselves will be refined; and the size and shape of the geographic study area will change. This is one of three draft reports that summarize the first phase of the four-phased HEDR Project. This, the Summary Report, is directed to readers who want a general understanding of the Phase 1 work and preliminary dose estimates. The two other reports -- the Air Pathway Report and the Columbia River Pathway Report -- are for readers who understand the radiation dose assessment process and want to see more technical detail. Detailed descriptions of the dose reconstruction process are available in more than 20 supporting reports listed in Appendix A. 32 refs., 46 figs.

  18. SU-E-J-36: Combining CBCT Dose Into IMRT Treatment Planning

    SciTech Connect (OSTI)

    Grelewicz, Z; Wiersma, R [The University of Chicago, Chicago, IL (United States)

    2014-06-01T23:59:59.000Z

    Purpose: Cone beam CT (CBCT) is increasingly used in patient setup for IMRT. Daily CBCT may provide effective localization, however, it introduces concern over excessive imaging dose. Previous studies investigated the calculation of excess CBCT dose, however, no study has yet treated this dose as a source of therapeutic radiation, optimized in consideration of PTV and OARs constrains. Here we present a novel combined MV+kV inverse optimization engine to weave the CBCT and MV dose together such that CBCT dose is used for both imaging and therapeutic purposes. This may mitigate some of the excess imaging dose effects of daily CBCT and allow complete evaluation of the CBCT dose prior to treatment. Methods: The EGSnrc Monte Carlo system was used to model a Varian Trilogy CBCT system and 6 MV treatment beam. Using the model, the dose to patient from treatment beam and imaging beam was calculated for ten patients. The standard IMRT objective function was modified to include CBCT dose. Treatment plan optimization using the MOSEK optimization tool was performed retrospectively with and without assuming kV radiation dose from CBCT, assuming one CBCT per fraction. Results: Across ten patients, the CBCT delivered peaks of between .4% and 3.0% of the prescription dose to the PTV, with average CBCT dose to the PTV between .3% and .8%. By including CBCT dose to skin as a constraint during optimization, peak skin dose is reduced by between 1.9% and 7.4%, and average skin dose is reduced by .2% to 3.3%. Conclusions: Pre-treatment CBCT may deliver a substantial amount of radiation dose to the target volume. By considering CBCT dose to skin at the point of treatment planning, it is possible to reduce patient skin dose from current clinical levels, and to provide patient treatment with the improved accuracy that daily CBCT provides.

  19. Radiation Hardness and Linearity Studies of CVD Diamonds

    E-Print Network [OSTI]

    T. Behnke; M. Doucet; N. Ghodbane; A. Imhof

    2002-12-09T23:59:59.000Z

    We report on the behavior of CVD diamonds under intense electromagnetic radiation and on the response of the detector to high density of deposited energy. Diamonds have been found to remain unaffected after doses of 10 MGy of MeV-range photons and the diamond response to energy depositions of up to 250 GeV/cm^3 has been found to be linear to better than 2 %. These observations make diamond an attractive detector material for a calorimeter in the very forward region of the detector proposed for TESLA.

  20. Transient radiation-induced absorption in laser materials

    SciTech Connect (OSTI)

    Brannon, P.J.

    1994-12-31T23:59:59.000Z

    Transient radiation-induced absorption losses in laser materials have been measured using a pulsed nuclear reactor. Reactor pulse widths of 70 to 90 {mu}s and absorbed doses of 1 to 7.5 krad have been used. Transmission recovery times and peak absorption coefficients are given. Materials tested include LiNbO{sub 3}, GSGG, silica substrates, and filter glasses used in the laser cavity. The filter glasses are tested at discrete wavelengths in the range 440--750 nm. Lithium niobate , MgO doped LiNbO{sub 3}, GSGG, and the silica substrates are tested at 1061 nm.

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

    DOE Patents [OSTI]

    Roybal, Lyle Gene

    2010-06-08T23:59:59.000Z

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

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

    SciTech Connect (OSTI)

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

    1993-12-31T23:59:59.000Z

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

  3. Hanford Environmental Dose Reconstruction Project. Quarterly report, June--August 1993

    SciTech Connect (OSTI)

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

    1993-10-01T23:59:59.000Z

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

  4. Dose-equivalent neutron dosimeter

    DOE Patents [OSTI]

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

    1981-01-07T23:59:59.000Z

    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.

  5. Enhanced radiation resistant fiber optics

    DOE Patents [OSTI]

    Lyons, P.B.; Looney, L.D.

    1993-11-30T23:59:59.000Z

    A process for producing an optical fiber having enhanced radiation resistance is provided, the process including maintaining an optical fiber within a hydrogen-containing atmosphere for sufficient time to yield a hydrogen-permeated optical fiber having an elevated internal hydrogen concentration, and irradiating the hydrogen-permeated optical fiber at a time while the optical fiber has an elevated internal hydrogen concentration with a source of ionizing radiation. The radiation source is typically a cobalt-60 source and the fiber is pre-irradiated with a dose level up to about 1000 kilorads of radiation. 4 figures.

  6. Enhanced radiation resistant fiber optics

    DOE Patents [OSTI]

    Lyons, Peter B. (Los Alamos, NM); Looney, Larry D. (Los Alamos, NM)

    1993-01-01T23:59:59.000Z

    A process for producing an optical fiber having enhanced radiation resitance is provided, the process including maintaining an optical fiber within a hydrogen-containing atmosphere for sufficient time to yield a hydrogen-permeated optical fiber having an elevated internal hydrogen concentration, and irradiating the hydrogen-permeated optical fiber at a time while the optical fiber has an elevated internal hydrogen concentration with a source of ionizing radiation. The radiation source is typically a cobalt-60 source and the fiber is pre-irradiated with a dose level up to about 1000 kilorads of radiation.

  7. Limitations of the TG-43 formalism for skin high-dose-rate brachytherapy dose calculations

    SciTech Connect (OSTI)

    Granero, Domingo, E-mail: dgranero@eresa.com [Department of Radiation Physics, ERESA, Hospital General Universitario, 46014 Valencia (Spain)] [Department of Radiation Physics, ERESA, Hospital General Universitario, 46014 Valencia (Spain); Perez-Calatayud, Jose [Radiotherapy Department, La Fe University and Polytechnic Hospital, Valencia 46026 (Spain)] [Radiotherapy Department, La Fe University and Polytechnic Hospital, Valencia 46026 (Spain); Vijande, Javier [Department of Atomic, Molecular and Nuclear Physics, University of Valencia, Burjassot 46100, Spain and IFIC (UV-CSIC), Paterna 46980 (Spain)] [Department of Atomic, Molecular and Nuclear Physics, University of Valencia, Burjassot 46100, Spain and IFIC (UV-CSIC), Paterna 46980 (Spain); Ballester, Facundo [Department of Atomic, Molecular and Nuclear Physics, University of Valencia, Burjassot 46100 (Spain)] [Department of Atomic, Molecular and Nuclear Physics, University of Valencia, Burjassot 46100 (Spain); Rivard, Mark J. [Department of Radiation Oncology, Tufts University School of Medicine, Boston, Massachusetts 02111 (United States)] [Department of Radiation Oncology, Tufts University School of Medicine, Boston, Massachusetts 02111 (United States)

    2014-02-15T23:59:59.000Z

    Purpose: In skin high-dose-rate (HDR) brachytherapy, sources are located outside, in contact with, or implanted at some depth below the skin surface. Most treatment planning systems use the TG-43 formalism, which is based on single-source dose superposition within an infinite water medium without accounting for the true geometry in which conditions for scattered radiation are altered by the presence of air. The purpose of this study is to evaluate the dosimetric limitations of the TG-43 formalism in HDR skin brachytherapy and the potential clinical impact. Methods: Dose rate distributions of typical configurations used in skin brachytherapy were obtained: a 5 cm × 5 cm superficial mould; a source inside a catheter located at the skin surface with and without backscatter bolus; and a typical interstitial implant consisting of an HDR source in a catheter located at a depth of 0.5 cm. Commercially available HDR{sup 60}Co and {sup 192}Ir sources and a hypothetical {sup 169}Yb source were considered. The Geant4 Monte Carlo radiation transport code was used to estimate dose rate distributions for the configurations considered. These results were then compared to those obtained with the TG-43 dose calculation formalism. In particular, the influence of adding bolus material over the implant was studied. Results: For a 5 cm × 5 cm{sup 192}Ir superficial mould and 0.5 cm prescription depth, dose differences in comparison to the TG-43 method were about ?3%. When the source was positioned at the skin surface, dose differences were smaller than ?1% for {sup 60}Co and {sup 192}Ir, yet ?3% for {sup 169}Yb. For the interstitial implant, dose differences at the skin surface were ?7% for {sup 60}Co, ?0.6% for {sup 192}Ir, and ?2.5% for {sup 169}Yb. Conclusions: This study indicates the following: (i) for the superficial mould, no bolus is needed; (ii) when the source is in contact with the skin surface, no bolus is needed for either {sup 60}Co and {sup 192}Ir. For lower energy radionuclides like {sup 169}Yb, bolus may be needed; and (iii) for the interstitial case, at least a 0.1 cm bolus is advised for {sup 60}Co to avoid underdosing superficial target layers. For {sup 192}Ir and {sup 169}Yb, no bolus is needed. For those cases where no bolus is needed, its use might be detrimental as the lack of radiation scatter may be beneficial to the patient, although the 2% tolerance for dose calculation accuracy recommended in the AAPM TG-56 report is not fulfilled.

  8. X-ray induced Sm{sup 3+} to Sm{sup 2+} conversion in fluorophosphate and fluoroaluminate glasses for the monitoring of high-doses in microbeam radiation therapy

    SciTech Connect (OSTI)

    Vahedi, Shahrzad; Okada, Go; Morrell, Brian; Muzar, Edward; Koughia, Cyril; Kasap, Safa [Department of Electrical and Computer Engineering, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5A9 (Canada); Edgar, Andy; Varoy, Chris [School of Chemical and Physical Sciences and MacDiarmid Institute, Victoria University of Wellington, Kelburn Parade (New Zealand); Belev, George; Wysokinski, Tomasz [Canadian Light Source, Inc., University of Saskatchewan, Saskatoon, Saskatchewan S7N 0X4 (Canada); Chapman, Dean [Department of Anatomy and Cell Biology, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5E5 (Canada)

    2012-10-01T23:59:59.000Z

    Fluorophosphate and fluoroaluminate glasses doped with trivalent samarium were evaluated as sensors of x-ray radiation for microbeam radiation therapy at the Canadian Light Source using the conversion of trivalent Sm{sup 3+} to the divalent form Sm{sup 2+}. Both types of glasses show similar conversion rates and may be used as a linear sensor up to {approx}150 Gy and as a nonlinear sensor up to {approx}2400 Gy, where saturation is reached. Experiments with a multi-slit collimator show high spatial resolution of the conversion pattern; the pattern was acquired by a confocal fluorescence microscopy technique. The effects of previous x-ray exposure may be erased by annealing at temperatures exceeding the glass transition temperature T{sub g} while annealing at T{sub A} < T{sub g} enhances the Sm conversion. This enhancement is explained by a thermally stimulated relaxation of host glass ionic matrix surrounding x-ray induced Sm{sup 2+} ions. In addition, some of the Sm{sup 3+}-doped glasses were codoped with Eu{sup 2+}-ions but the results show that there is no marked improvement in the conversion efficiency by the introduction of Eu{sup 2+}.

  9. RangeTables.xls

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What's PossibleRadiation Protection Radiation ProtectionRaising funds for a cure Raising2

  10. Variations of dose rate observed by MSL/RAD in transit to Mars

    E-Print Network [OSTI]

    Guo, Jingnan; Wimmer-Schweingruber, Robert F; Hassler, Donald M; Posner, Arik; Heber, Bernd; Köhler, Jan; Rafkin, Scot; Ehresmann, Bent; Appel, Jan K; Böhm, Eckart; Böttcher, Stephan; Burmeister, Sönke; Brinza, David E; Lohf, Henning; Martin, Cesar; Reitz, Günther

    2015-01-01T23:59:59.000Z

    Aims: To predict the cruise radiation environment related to future human missions to Mars, the correlation between solar modulation potential and the dose rate measured by the Radiation Assessment Detector (RAD) has been analyzed and empirical models have been employed to quantify this correlation. Methods: The instrument RAD, onboard Mars Science Laboratory's (MSL) rover Curiosity, measures a broad spectrum of energetic particles along with the radiation dose rate during the 253-day cruise phase as well as on the surface of Mars. With these first ever measurements inside a spacecraft from Earth to Mars, RAD observed the impulsive enhancement of dose rate during solar particle events as well as a gradual evolution of the galactic cosmic ray (GCR) induced radiation dose rate due to the modulation of the primary GCR flux by the solar magnetic field, which correlates with long-term solar activities and heliospheric rotation. Results: We analyzed the dependence of the dose rate measured by RAD on solar modulatio...

  11. Radiation: Radiation Control (Indiana)

    Broader source: Energy.gov [DOE]

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

  12. DOE 2012 Occupational Radiation Exposure October 2013

    SciTech Connect (OSTI)

    none,

    2012-02-02T23:59:59.000Z

    The U.S. Department of Energy (DOE) Office of Analysis within the Office of Health, Safety and Security (HSS) publishes the annual DOE Occupational Radiation Exposure Report to provide an overview of the status of radiation protection practices at DOE (including the National Nuclear Security Administration [NNSA]). The DOE 2012 Occupational Radiation Exposure Report provides an evaluation of DOE-wide performance regarding compliance with Title 10, Code of Federal Regulations (C.F.R.), Part 835, Occupational Radiation Protection dose limits and as low as reasonably achievable (ALARA) process requirements. In addition, the report provides data to DOE organizations responsible for developing policies for protection of individuals from the adverse health effects of radiation. The report provides a summary and an analysis of occupational radiation exposure information from the monitoring of individuals involved in DOE activities. Over the past 5-year period, the occupational radiation exposure information is analyzed in terms of aggregate data, dose to individuals, and dose by site. As an indicator of the overall amount of radiation dose received during the conduct of operations at DOE, the report includes information on collective total effective dose (TED). The TED is comprised of the effective dose (ED) from external sources, which includes neutron and photon radiation, and the internal committed effective dose (CED), which results from the intake of radioactive material into the body. The collective ED from photon exposure decreased by 23% between 2011 and 2012, while the neutron dose increased by 5%. The internal dose components of the collective TED decreased by 7%. Over the past 5-year period, 99.99% of the individuals receiving measurable TED have received doses below the 2 roentgen equivalent in man (rems) (20 millisievert [mSv]) TED administrative control level (ACL), which is well below the DOE regulatory limit of 5 rems (50 mSv) TED annually. The occupational radiation exposure records show that in 2012, DOE facilities continued to comply with DOE dose limits and ACLs and worked to minimize exposure to individuals. The DOE collective TED decreased 17.1% from 2011 to 2012. The collective TED decreased at three of the five sites with the largest collective TED. u Idaho Site – Collective dose reductions were achieved as a result of continuing improvements at the Advanced Mixed Waste Treatment Project (AMWTP) through the planning of drum movements that reduced the number of times a container is handled; placement of waste containers that created highradiation areas in a centralized location; and increased worker awareness of high-dose rate areas. In addition, Idaho had the largest decrease in the total number of workers with measurable TED (1,143 fewer workers). u Hanford Site (Hanford) – An overall reduction of decontamination and decommissioning (D&D) activities at the Plutonium Finishing Plant (PFP) and Transuranic (TRU) retrieval activities resulted in collective dose reductions. u Savannah River Site (SRS) – Reductions were achieved through ALARA initiatives employed site wide. The Solid Waste Management Facility used extended specialty tools, cameras and lead shield walls to facilitate removal of drums. These tools and techniques reduce exposure time through improved efficiency, increase distance from the source of radiation by remote monitoring, shield the workers to lower the dose rate, and reduce the potential for contamination and release of material through repacking of waste. Overall, from 2011 to 2012, there was a 19% decrease in the number of workers with measurable dose. Furthermore, due to a slight decrease in both the DOE workforce (7%) and monitored workers (10%), the ratio of workers with measurable doses to monitored workers decreased to 13%. Another primary indicator of the level of radiation exposure covered in this report is the average measurable dose, which normalizes the collective dose over the population of workers who actually received a measurable dose. The average measurable TED in

  13. Wide-range monitor for pulsed x-ray sources

    SciTech Connect (OSTI)

    Kaifer, R.C.; Jenkins, T.E.; Straume, T.

    1981-10-12T23:59:59.000Z

    A monitoring instrument based on a high-pressure ionization chamber has been developed that measures average dose rates as low as 0.1 mR/h and responds linearly to short pulses at dose rates up to 1.2 x 10/sup 10/ R/h. Its sensitivity can be remotely changed by a factor of 10/sup 4/, to enable accurate measurement of both background radiation and very high intensities such as can be expected from accelerator beam-spills. The instrument's detector-electrometer pulse response was measured using a dose-calibrated field-emission accelerator having a 30-ns pulse width.

  14. Dose reduction improvements in storage basins of spent nuclear fuel

    SciTech Connect (OSTI)

    Huang, Fan-Hsiung F.

    1997-08-13T23:59:59.000Z

    Spent nuclear fuel in storage basins at the Hanford Site has corroded and contaminated basin water, which has leaked into the soil; the fuel also had deposited a layer of radioactive sludge on basin floors. The SNF is to be removed from the basins to protect the nearby Columbia River. Because the radiation level is high, measures have been taken to reduce the background dose rate to as low as reasonably achievable (ALARA) to prevent radiation doses from becoming the limiting factor for removal of the SW in the basins to long-term dry storage. All activities of the SNF Project require application of ALARA principles for the workers. On the basis of these principles dose reduction improvements have been made by first identifying radiological sources. Principal radiological sources in the basin are basin walls, basin water, recirculation piping and equipment. Dose reduction activities focus on cleaning and coating basin walls to permit raising the water level, hydrolasing piping, and placing lead plates. In addition, the transfer bay floor will be refinished to make decontamination easier and reduce worker exposures in the radiation field. The background dose rates in the basin will be estimated before each task commences and after it is completed; these dose reduction data will provide the basis for cost benefit analysis.

  15. Cancer risk estimates from radiation therapy for heterotopic ossification prophylaxis after total hip arthroplasty

    SciTech Connect (OSTI)

    Mazonakis, Michalis; Berris, Theoharris; Damilakis, John [Department of Medical Physics, Faculty of Medicine, University of Crete, P.O. Box 2208, 71003 Iraklion, Crete (Greece)] [Department of Medical Physics, Faculty of Medicine, University of Crete, P.O. Box 2208, 71003 Iraklion, Crete (Greece); Lyraraki, Efrossyni [Department of Radiotherapy and Oncology, University Hospital of Iraklion, 71110 Iraklion, Crete (Greece)] [Department of Radiotherapy and Oncology, University Hospital of Iraklion, 71110 Iraklion, Crete (Greece)

    2013-10-15T23:59:59.000Z

    Purpose: Heterotopic ossification (HO) is a frequent complication following total hip arthroplasty. This study was conducted to calculate the radiation dose to organs-at-risk and estimate the probability of cancer induction from radiotherapy for HO prophylaxis.Methods: Hip irradiation for HO with a 6 MV photon beam was simulated with the aid of a Monte Carlo model. A realistic humanoid phantom representing an average adult patient was implemented in Monte Carlo environment for dosimetric calculations. The average out-of-field radiation dose to stomach, liver, lung, prostate, bladder, thyroid, breast, uterus, and ovary was calculated. The organ-equivalent-dose to colon, that was partly included within the treatment field, was also determined. Organ dose calculations were carried out using three different field sizes. The dependence of organ doses upon the block insertion into primary beam for shielding colon and prosthesis was investigated. The lifetime attributable risk for cancer development was estimated using organ, age, and gender-specific risk coefficients.Results: For a typical target dose of 7 Gy, organ doses varied from 1.0 to 741.1 mGy by the field dimensions and organ location relative to the field edge. Blocked field irradiations resulted in a dose range of 1.4–146.3 mGy. The most probable detriment from open field treatment of male patients was colon cancer with a high risk of 564.3 × 10{sup ?5} to 837.4 × 10{sup ?5} depending upon the organ dose magnitude and the patient's age. The corresponding colon cancer risk for female patients was (372.2–541.0) × 10{sup ?5}. The probability of bladder cancer development was more than 113.7 × 10{sup ?5} and 110.3 × 10{sup ?5} for males and females, respectively. The cancer risk range to other individual organs was reduced to (0.003–68.5) × 10{sup ?5}.Conclusions: The risk for cancer induction from radiation therapy for HO prophylaxis after total hip arthroplasty varies considerably by the treatment parameters, organ site in respect to treatment volume and patient's gender and age. The presented risk estimates may be useful in the follow-up studies of irradiated patients.

  16. Overview of the Hanford Environmental Dose Reconstruction Project

    SciTech Connect (OSTI)

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

    1992-04-01T23:59:59.000Z

    The objective of the Hanford Environmental Dose Reconstruction (HEDR) Project is to estimate the radiation doses that specific and representative individuals and populations may have received as a result of releases of radioactive materials from historical operations at the Hanford Site. These dose estimates would account for the uncertainties of information regarding facilities operations, environmental monitoring, demography, food consumption and lifestyles, and the variability of natural phenomena. Other objectives of the HEDR Project include: supporting the Hanford Thyroid Disease Study (HTDS), declassifying Hanford-generated information and making it available to the public, performing high-quality, credible science, and conducting the project in an open, public forum. The project is briefly described.

  17. Determination of radionuclides and pathways contributing to cumulative dose

    SciTech Connect (OSTI)

    Napier, B.A.

    1992-12-01T23:59:59.000Z

    A series of scoping calculations has been undertaken to evaluate the absolute and relative contributions of different radionuclides and exposure pathways to doses that may have been received by individuals living in the vicinity of the Hanford Site. This scoping calculation (Calculation 004) examined the contributions of numerous radionuclides to cumulative dose via environmental exposures and accumulation in foods. Addressed in this calculation were the contributions to organ and effective dose of infants and adults from (1) air submersion and groundshine external dose, (2) inhalation, (3) ingestion of soil by humans, (4) ingestion of leafy vegetables, (5) ingestion of other vegetables and fruits, (6) ingestion of meat, (7) ingestion of eggs, and (8) ingestion of cows' milk from Feeding Regime 1, as described in calculation 002. This calculation specifically addresses cumulative radiation doses to infants and adults resulting from releases occurring over the period 1945 through 1972.

  18. Change of Primary Cosmic Radiation Nuclear Conposition in the Energy Range $10^{15} - 10^{17}$ eV as a Result of the Interaction with the Interstellar Cold Background of Light Particles

    E-Print Network [OSTI]

    T. T. Barnaveli; T. T. Barnaveli Jr; N. A. Eristavi; I. V. Khaldeeva

    2003-10-19T23:59:59.000Z

    In this paper the updated arguments in favor of a simple model, explaining from the united positions all peculiarities of the Extensive Air Shower (EAS) hadron E_h(E_0) (and muon E_mu(E_0)) component energy fluxes dependence on the primary particle energy E_0 in the primary energy region 10^{15} - 10^{17} eV are represented. These peculiarities have shapes of consequent distinct deeps of a widths dE_h/E_h of the order of 0.2 and of relative amplitudes dL/L of the order of {0.1 - 1.0}, and are difficult to be explained via known astrophysical mechanisms of particle generation and acceleration. In the basis of the model lies the destruction of the Primary Cosmic Radiation (PCR) nuclei on some monochromatic background of interstellar space, consisting of the light particles of the mass in the area of 36 eV (maybe the component of a dark matter). The destruction thresholds of PCR different nuclear components correspond to the peculiarities of E_h(E_0). In this work the results of the recent treatment of large statistical material are analyzed. The experimental results are in good agreement with the Monte-Carlo calculations carried out in the frames of the proposed model.

  19. Effects of low levels of radiation on humans

    SciTech Connect (OSTI)

    Auxier, J.A.

    1981-01-01T23:59:59.000Z

    The state of knowledge on effects of low-level ionizing radiations on humans is reviewed. Several problems relating to dose thresholds or lack of thresholds for several types of cancer and high LET radiations and the effects of fractionation and dose protection are discussed. (ACR)

  20. RangeTables.xlsx

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What's PossibleRadiation Protection Radiation ProtectionRaising funds for a cure Raising2Vcm²/mg) LET

  1. RangeTables.xlsx

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What's PossibleRadiation Protection Radiation ProtectionRaising funds for a cure Raising2Vcm²/mg) LET 30

  2. GENII. Environmental Radiation Dosimetry Suite

    SciTech Connect (OSTI)

    Napier, B.A. [Pacific Northwest Lab., Richland, WA, (United States)

    1988-12-01T23:59:59.000Z

    GENII was developed to incorporate the internal dosimetry models recommended by the International Commission on Radiological Protection (ICRP) into the environmental pathway analysis models used at Hanford. GENII is a coupled system of seven programs and the associated data libraries that comprise the Hanford Dosimetry System (Generation II) to estimate potential radiation doses to individuals or populations from both routine and accidental releases of radionuclides to air or water and residual contamination from spills or decontamination operations. The GENII system includes interactive menu-driven programs to assist the user with scenario generation and data input,internal and external dose factor generators, and environmental dosimetry programs. The programs analyze environmental contamination resulting from both far-field and near-field scenarios. A far-field scenario focuses outward from a source, while a near-field scenario focuses in toward a receptor. GENII can calculate annual dose, committed dose, and accumulated dose from acute and chronic releases from ground or elevated sources to air or water and from initial contamination of soil or surfaces and can evaluate exposure pathways including direct exposure via water, soil, air, inhalation pathways, and ingestion pathways. In addition, GENII can perform 10,000 years migration analyses and can be used for retrospective calculations of potential radiation doses resulting from routine emissions and for prospective dose calculations for purposes such as siting facilities, environmental impact statements, and safety analysis reports.

  3. Radiation-Associated Liver Injury

    SciTech Connect (OSTI)

    Pan, Charlie C., E-mail: cpan@umich.ed [Department of Radiation Oncology, University of Michigan Medical School, Ann Arbor, MI (United States); Kavanagh, Brian D. [Department of Radiation Oncology, University of Colorado, Aurora, CO (United States); Dawson, Laura A. [Princess Margaret Hospital, University of Toronto, Toronto, Ontario (Canada); Li, X. Allen [Department of Radiation Oncology, Medical College of Wisconsin, Milwaukee, WI (United States); Das, Shiva K. [Department of Radiation Oncology, Duke University Medical Center, Durham, NC (United States); Miften, Moyed [Department of Radiation Oncology, University of Colorado, Aurora, CO (United States); Ten Haken, Randall K. [Department of Radiation Oncology, University of Michigan Medical School, Ann Arbor, MI (United States)

    2010-03-01T23:59:59.000Z

    The liver is a critically important organ that has numerous functions including the production of bile, metabolism of ingested nutrients, elimination of many waste products, glycogen storage, and plasma protein synthesis. The liver is often incidentally irradiated during radiation therapy (RT) for tumors in the upper- abdomen, right lower lung, distal esophagus, or during whole abdomen or whole body RT. This article describes the endpoints, time-course, and dose-volume effect of radiation on the liver.

  4. Low-Dose Radiotherapy in Indolent Lymphoma

    SciTech Connect (OSTI)

    Rossier, Christine [Department of Radiation Oncology, Centre Hospitalier Universitaire Vaudois, Lausanne (Switzerland); Schick, Ulrike; Miralbell, Raymond [Department of Radiation Oncology, University Hospital of Geneva (Switzerland); Mirimanoff, Rene O. [Department of Radiation Oncology, Centre Hospitalier Universitaire Vaudois, Lausanne (Switzerland); Weber, Damien C. [Department of Radiation Oncology, University Hospital of Geneva (Switzerland); Ozsahin, Mahmut, E-mail: Esat-Mahmut.Ozsahin@chuv.ch [Department of Radiation Oncology, Centre Hospitalier Universitaire Vaudois, Lausanne (Switzerland)

    2011-11-01T23:59:59.000Z

    Purpose: To assess the response rate, duration of response, and overall survival after low-dose involved-field radiotherapy in patients with recurrent low-grade lymphoma or chronic lymphocytic leukemia (CLL). Methods and Materials: Forty-three (24 women, 19 men) consecutive patients with indolent lymphoma or CLL were treated with a total dose of 4 Gy (2 x 2 Gy) using 6- 18-MV photons. The median age was 73 years (range, 39-88). Radiotherapy was given either after (n = 32; 75%) or before (n = 11; 25%) chemotherapy. The median time from diagnosis was 48 months (range, 1-249). The median follow-up period was 20 months (range, 1-56). Results: The overall response rate was 90%. Twelve patients (28%) had a complete response, 15 (35%) had a partial response, 11 (26%) had stable disease, and 5 (11%) had progressive disease. The median overall survival for patients with a positive response (complete response/partial response/stable disease) was 41 months; for patients with progressive disease it was 6 months (p = 0.001). The median time to in-field progression was 21 months (range, 0-24), and the median time to out-field progression was 8 months (range, 0-40). The 3-year in-field control was 92% in patients with complete response (median was not reached). The median time to in-field progression was 9 months (range, 0.5-24) in patients with partial response and 6 months (range, 0.6-6) in those with stable disease (p < 0.05). Younger age, positive response to radiotherapy, and no previous chemotherapy were the best factors influencing the outcome. Conclusions: Low-dose involved-field radiotherapy is an effective treatment in the management of patients with recurrent low-grade lymphoma or CLL.

  5. A prospective study on radiation-induced changes in hearing function

    SciTech Connect (OSTI)

    Herrmann, Franziska [Department of Oto-Rhino-Laryngology, University of Technology-Dresden, Dresden (Germany); Doerr, Wolfgang [Department of Radiotherapy and Radiation Oncology, University of Technology-Dresden, Dresden (Germany); Experimental Center, Medical Faculty Carl Gustav Carus, University of Technology-Dresden, Dresden (Germany); Mueller, Rainer [Department of Oto-Rhino-Laryngology, University of Technology-Dresden, Dresden (Germany); Herrmann, Thomas [Department of Radiotherapy and Radiation Oncology, University of Technology-Dresden, Dresden (Germany)]. E-mail: thomas.herrmann@mailbox.tu-dresden.de

    2006-08-01T23:59:59.000Z

    Purpose: To quantitate changes in hearing function after radiotherapy for head-and-neck tumors. Methods and Materials: At the Department of Radiotherapy and Radiation Oncology, 32 patients were irradiated for head-and-neck tumors. Three-dimensional treatment planning was applied. Total tumor doses were 30.0-77.6 Gy, local doses to the inner ear (n = 64) ranged from 1.7 to 64.3 Gy. Audiometry was performed before the onset of radiotherapy (RT), at a tumor dose of 40 Gy or at the end of palliative treatment, at the end of curative RT, and 2-6 months post-RT. Assays applied were frequency-specific threshold measurements for air and bone conduction, measurements according to Weber and Rinne, tympanometry and assessment of the stapedius reflex. Results: Age and prior disease significantly decreased, whereas previous or concurrent alcohol consumption significantly increased hearing ability. A significant reduction in hearing ability during RT was found for high frequencies (at 40 Gy) and low frequencies (at end of RT), which persisted after RT. No differences were observed for air or bone conduction. None of the other assays displayed time- or dose-dependent changes. Dose-effect analyses revealed an ED50 (dose at which a 50% incidence is expected) for significant changes in hearing thresholds (15 dB) in the range of 20-25 Gy, with large confidence limits. Conclusions: Radiation effects on hearing ability were confined to threshold audiogram values, which started during the treatment without reversibility during 6 months postradiotherapy.

  6. DOE 2011 Occupational Radiation Exposure report, _Prepared for the U.S. Department of Energy, Office of Health, Safety and Security. December 2012

    SciTech Connect (OSTI)

    Derek Hagemeyer, Yolanda McCormick

    2012-12-12T23:59:59.000Z

    This report discusses radiation protection and dose reporting requirements, presents the 2011 occupational radiation dose data along with trends over the past 5 years, and provides instructions to submit successful as low as reasonably achievable (ALARA) projects.

  7. DOE Radiation Exposure Monitoring System (REMS) Data Update

    SciTech Connect (OSTI)

    Rao, Nimi; Hagemeyer, Derek

    2012-05-05T23:59:59.000Z

    This slide show presents the 2011 draft data for DOE occupational radiation exposure.Clarification is given on Reporting Data regarding: reporting Total Organ Dose (TOD); reporting Total Skin Dose (TSD), and Total Extremity Dose (TExD) ; and Special individuals reporting.

  8. GROUND-WATER CONTRIBUTION TO DOSE FROM PAST HANFORD OPERATIONS

    SciTech Connect (OSTI)

    Freshley, M. D.; Thorne, P. D.

    1992-01-01T23:59:59.000Z

    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.

  9. Prospective Study of Local Control and Late Radiation Toxicity After Intraoperative Radiation Therapy Boost for Early Breast Cancer

    SciTech Connect (OSTI)

    Chang, David W., E-mail: David.Chang@petermac.org [Division of Radiation Oncology and Cancer Imaging, Peter MacCallum Cancer Centre, Melbourne, Victoria (Australia); Marvelde, Luc te [Centre for Biostatistics and Clinical Trials, Peter MacCallum Cancer Centre, Melbourne, Victoria (Australia); Chua, Boon H. [Division of Radiation Oncology and Cancer Imaging, Peter MacCallum Cancer Centre, Melbourne, Victoria (Australia); Sir Peter MacCallum Department of Oncology, University of Melbourne, Melbourne, Victoria (Australia)

    2014-01-01T23:59:59.000Z

    Purpose: To report the local recurrence rate and late toxicity of intraoperative radiation therapy (IORT) boost to the tumor bed using the Intrabeam System followed by external-beam whole-breast irradiation (WBI) in women with early-stage breast cancer in a prospective single-institution study. Methods and Materials: Women with breast cancer ?3 cm were recruited between February 2003 and May 2005. After breast-conserving surgery, a single dose of 5 Gy IORT boost was delivered using 50-kV x-rays to a depth of 10 mm from the applicator surface. This was followed by WBI to a total dose of 50 Gy in 25 fractions. Patients were reviewed at regular, predefined intervals. Late toxicities were recorded using the Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer Late Radiation Morbidity Scoring systems. Results: Fifty-five patients completed both IORT boost and external-beam WBI. Median follow-up was 3.3 years (range, 1.4-4.1 years). There was no reported locoregional recurrence or death. One patient developed distant metastases. Grade 2 and 3 subcutaneous fibrosis was detected in 29 (53%) and 8 patients (15%), respectively. Conclusions: The use of IORT as a tumor bed boost using kV x-rays in breast-conserving therapy was associated with good local control but a clinically significant rate of grade 2 and 3 subcutaneous fibrosis.

  10. Ionizing radiation detector

    DOE Patents [OSTI]

    Thacker, Louis H. (Knoxville, TN)

    1990-01-01T23:59:59.000Z

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

  11. Whole-body radiation dosimetry of 2-[F-18]fluoro-A-85380 in human PET imaging studies

    E-Print Network [OSTI]

    Obrzut, S L; Koren, A O; Mandelkern, M A; Brody, A L; Hoh, C K; London, E D

    2005-01-01T23:59:59.000Z

    body biodistribution, radiation absorbed dose, and brainM. Biodistribution and radiation dosimetry of 18 F-fluoro-A-Whole-Body Radiation Dosimetry of 2-[ 18 F]Fluoro-A-85380 in

  12. Pediatric radiation oncology

    SciTech Connect (OSTI)

    Halperin, E.C.; Kun, L.E.; Constine, L.S.; Tarbell, N.J.

    1989-01-01T23:59:59.000Z

    This text covers all aspects of radiation therapy for treatment of pediatric cancer. The book describes the proper use of irradiation in each of the malignancies of childhood, including tumors that are rarely encountered in adult practice. These include acute leukemia; supratentorial brain tumors; tumors of the posterior fossa of the brain and spinal canal; retinoblastoma and optic nerve glioma; neuroblastoma; Hodgkin's disease; malignant lymphoma; Ewing's sarcoma; osteosarcoma; rhabdomyosarcoma; Desmoid tumor; Wilms' tumor; liver and biliary tumors; germ cell and stromal cell tumors of the gonads; endocrine, aerodigestive tract, and breast tumors; Langerhans' cell histiocytosis; and skin cancer and hemangiomas. For each type of malignancy, the authors describe the epidemiology, common presenting signs and symptoms, staging, and proper diagnostic workup. Particular attention is given to the indications for radiation therapy and the planning of a course of radiotherapy, including the optimal radiation dose, field size, and technique.

  13. Calculation of external dose from distributed source

    SciTech Connect (OSTI)

    Kocher, D.C.

    1986-01-01T23:59:59.000Z

    This paper discusses a relatively simple calculational method, called the point kernel method (Fo68), for estimating external dose from distributed sources that emit photon or electron radiations. The principles of the point kernel method are emphasized, rather than the presentation of extensive sets of calculations or tables of numerical results. A few calculations are presented for simple source geometries as illustrations of the method, and references and descriptions are provided for other caluclations in the literature. This paper also describes exposure situations for which the point kernel method is not appropriate and other, more complex, methods must be used, but these methods are not discussed in any detail.

  14. The NCI Radiation Research Program: Grant portfolio and radiation

    E-Print Network [OSTI]

    models (89 animals no human subject material, 21 use both) ­ 109 utilize rodent models ­ 2 have canine and R37s). Of those that utilize radiation: · 6 use tissue culture models only · 110 utilize animal subjects · 39 use human subjects or human subject materials only. #12;Dose and Dosimetry · The majority

  15. FY 1992 revised task plans for the Hanford Environmental Dose Reconstruction Project

    SciTech Connect (OSTI)

    Shipler, D.B.

    1992-04-01T23:59:59.000Z

    The purpose of the Hanford Environmental Dose Reconstruction (HEDR) Project is to estimate radiation doses from Hanford Site operations since 1944 to populations and individuals. The primary objectives of work to be performed in FY 1992 is to determine the appropriate scope (space, time, and radionuclides, pathways and individuals/population groups) and accuracy (level of uncertainty in dose estimates) for the project. Another objective is to use a refined computer model to estimate Native American tribal doses and individual doses for the Hanford Thyroid Disease Study (HTDS). Project scope and accuracy requirements defined in FY 1992 can translated into model and data requirements that must be satisfied during FY 1993.

  16. FY 1992 revised task plans for the Hanford Environmental Dose Reconstruction Project. Revision 1

    SciTech Connect (OSTI)

    Shipler, D.B.

    1992-04-01T23:59:59.000Z

    The purpose of the Hanford Environmental Dose Reconstruction (HEDR) Project is to estimate radiation doses from Hanford Site operations since 1944 to populations and individuals. The primary objectives of work to be performed in FY 1992 is to determine the appropriate scope (space, time, and radionuclides, pathways and individuals/population groups) and accuracy (level of uncertainty in dose estimates) for the project. Another objective is to use a refined computer model to estimate Native American tribal doses and individual doses for the Hanford Thyroid Disease Study (HTDS). Project scope and accuracy requirements defined in FY 1992 can translated into model and data requirements that must be satisfied during FY 1993.

  17. Method for radiation detection and measurement

    DOE Patents [OSTI]

    Miller, S.D.

    1993-12-21T23:59:59.000Z

    Dose of radiation to which a body of crystalline material has been exposed is measured by exposing the body to optical radiation at a first wavelength, which is greater than about 540 nm, and measuring optical energy emitted from the body by luminescence at a second wavelength, which is longer than the first wavelength. 9 figures.

  18. COLUMBIA UNIVERSITY PREGNANCY POLICY FOR RADIATION WORKERS

    E-Print Network [OSTI]

    Jia, Songtao

    COLUMBIA UNIVERSITY PREGNANCY POLICY FOR RADIATION WORKERS POLICY: Under applicable regulations and Federal statutes (2), it is the policy of the Columbia University to limit the radiation dose (3). Further, it is the policy of the Columbia University to provide counseling and education

  19. Method for radiation detection and measurement

    DOE Patents [OSTI]

    Miller, Steven D. (Richland, WA)

    1993-01-01T23:59:59.000Z

    Dose of radiation to which a body of crystalline material has been exposed is measured by exposing the body to optical radiation at a first wavelength, which is greater than about 540 nm, and measuring optical energy emitted from the body by luminescence at a second wavelength, which is longer than the first wavelength.

  20. SU-E-J-190: Characterization of Radiation Induced CT Number Changes in Tumor and Normal Lung During Radiation Therapy for Lung Cancer

    SciTech Connect (OSTI)

    Yang, C; Liu, F; Tai, A; Gore, E; Johnstone, C; Li, X [Medical College of Wisconsin Milwaukee WI (United States)

    2014-06-01T23:59:59.000Z

    Purpose: To measure CT number (CTN) changes in tumor and normal lung as a function of radiation therapy (RT) dose during the course of RT delivery for lung cancer using daily IGRT CT images and single respiration phase CT images. Methods: 4D CT acquired during planning simulation and daily 3D CT acquired during daily IGRT for 10 lung cancer cases randomly selected in terms of age, caner type and stage, were analyzed using an in-house developed software tool. All patients were treated in 2 Gy fractions to primary tumors and involved nodal regions. Regions enclosed by a series of isodose surfaces in normal lung were delineated. The obtained contours along with target contours (GTVs) were populated to each singlephase planning CT and daily CT. CTN in term of Hounsfield Unit (HU) of each voxel in these delineated regions were collectively analyzed using histogram, mean, mode and linear correlation. Results: Respiration induced normal lung CTN change, as analyzed from single-phase planning CTs, ranged from 9 to 23 (±2) HU for the patients studied. Normal lung CTN change was as large as 50 (±12) HU over the entire treatment course, was dose and patient dependent and was measurable with dose changes as low as 1.5 Gy. For patients with obvious tumor volume regression, CTN within the GTV drops monotonically as much as 10 (±1) HU during the early fractions with a total dose of 20 Gy delivered. The GTV and CTN reductions are significantly correlated with correlation coefficient >0.95. Conclusion: Significant RT dose induced CTN changes in lung tissue and tumor region can be observed during even the early phase of RT delivery, and may potentially be used for early prediction of radiation response. Single respiration phase CT images have dramatically reduced statistical noise in ROIs, making daily dose response evaluation possible.

  1. Acute radiation syndrones and their management

    SciTech Connect (OSTI)

    Cronkite, E.P.

    1988-01-01T23:59:59.000Z

    Radiation syndromes produced by large doses of ionizing radiation are divided into three general groups depending on dose of radiation and time after exposure. The CNS syndrome requires many thousands of rad, appears in minutes to hours, and kills within hours to days. The GIS appears after doses of a few hundred to 2000 rad. It is characterized by nausea, vomiting, diarrhea, and disturbances of water and electrolyte metabolism. It has a high mortality in the first week after exposure. Survivors will then experience the HS as a result of marrow aplasia. Depending on dose, survival is possible with antibiotic and transfusion therapy. The relationship of granulocyte depression to mortality in dogs and human beings is illustrated. The role of depth dose pattern of mortality of radiation exposure is described and used as an indication of why air exposure doses may be misleading. The therapy of radiation injury is described based on antibiotics, transfusion therapy, and use of molecular regulators. The limited role of matched allogenic bone marrow transplants is discussed. 52 refs., 13 figs.

  2. Phase 1 of the Hanford Environmental Dose Reconstruction Project

    SciTech Connect (OSTI)

    Not Available

    1990-07-20T23:59:59.000Z

    For more than 40 years, the US government made plutonium for nuclear weapons at the Hanford Site in southeastern Washington State. Radioactive materials were released to both the air and water from Hanford. People could have been exposed to these materials, called radionuclides. The Hanford Environmental Dose Reconstruction (HEDR) Project is a multi-year scientific study to estimate the radiation doses the public may have received as a results of these releases. The study began in 1988. During the first phase, scientists began to develop and test methods for reconstructing the radiation doses. To do this, scientists found or reconstructed information about the amount and type of radionuclides that were released from Hadford facilities, where they traveled in environment, and how they reached people. Information about the people who could have been exposed was also found or reconstructed. Scientists then developed a computer model that can estimate doses from radiation exposure received many years ago. All the information that had been gathered was fed into the computer model. Then scientists did a test run'' to see whether the model was working properly. As part of its test run,'' scientists asked the computer model to generate two types of preliminary results: amounts of radionuclides in the environment (air, soil, pasture grass, food, and milk) and preliminary doses people could have received from all the routes of radiation exposure, called exposure pathways. Preliminary dose estimates were made for categories of people who shared certain characteristics and for the Phase 1 population as a whole. 26 refs., 48 figs.

  3. Evaluation of offsite dose assessment methodologies used in the nuclear industry

    E-Print Network [OSTI]

    Berry, Robert Orwell

    1992-01-01T23:59:59.000Z

    power plant, special studies have been done to estimate the doses due to releases from these facilities. To establish a consistent methodology to be used in the determination of the radiation doses from nuclear power plants the U. S. Nuclear..., Part 20, "Standards for Protection Against Radiation" (10CFR20). Specific design objectives for light-water-cooled nuclear power reactors on exposure levels in unrestricted areas outside these facilities are presented in 10CFR50. Some of the newly...

  4. SU-E-J-04: A Data-Driven, Response-Based, Multi-Criteria Decision Support System for Personalized Lung Radiation Treatment Planning

    SciTech Connect (OSTI)

    Luo, Y; McShan, D; Schipper, M; Matuszak, M; Ten Haken, R [University of Michigan, Ann Arbor, MI (United States); Kong, F [Georgia Regents University, Augusta, GA (Georgia)

    2014-06-01T23:59:59.000Z

    Purpose: To develop a decision support tool to predict a patient's potential overall survival (OS) and radiation induced toxicity (RIT) based on clinical factors and responses during the course of radiotherapy, and suggest appropriate radiation dose adjustments to improve therapeutic effect. Methods: Important relationships between a patient's basic information and their clinical features before and during the radiation treatment are identified from historical clinical data by using statistical learning and data mining approaches. During each treatment period, a data analysis (DA) module predicts radiotherapy features such as time to local progression (TTLP), time to distant metastases (TTDM), radiation toxicity to different organs, etc., under possible future treatment plans based on patient specifics or responses. An information fusion (IF) module estimates intervals for a patient's OS and the probabilities of RIT from a treatment plan by integrating the outcomes of module DA. A decision making (DM) module calculates “satisfaction” with the predicted radiation outcome based on trade-offs between OS and RIT, and finds the best treatment plan for the next time period via multi-criteria optimization. Results: Using physical and biological data from 130 lung cancer patients as our test bed, we were able to train and implement the 3 modules of our decision support tool. Examples demonstrate how it can help predict a new patient's potential OS and RIT with different radiation dose plans along with how these combinations change with dose, thus presenting a range of satisfaction/utility for use in individualized decision support. Conclusion: Although the decision support tool is currently developed from a small patient sample size, it shows the potential for the improvement of each patient's satisfaction in personalized radiation therapy. The radiation treatment outcome prediction and decision making model needs to be evaluated with more patients and demonstrated for use in radiation treatments for other cancers. P01-CA59827;R01CA142840.

  5. Monte Carlo Simulations of Grid Walled Proportional Counters with Different Site Sizes for HZE Radiation

    E-Print Network [OSTI]

    Liu, Haifeng

    2012-07-16T23:59:59.000Z

    Tissue-equivalent proportional counters are frequently used to measure dose and dose equivalent in cosmic radiation fields that include high-Z, high-energy (HZE) particles. The fact that particles with different stopping powers can produce the same...

  6. Long range global warming

    SciTech Connect (OSTI)

    Rolle, K.C.; Pulkrabek, W.W.; Fiedler, R.A. [Univ. of Wisconsin, Platteville, WI (United States)

    1995-12-31T23:59:59.000Z

    This paper explores one of the causes of global warming that is often overlooked, the direct heating of the environment by engineering systems. Most research and studies of global warming concentrate on the modification that is occurring to atmospheric air as a result of pollution gases being added by various systems; i.e., refrigerants, nitrogen oxides, ozone, hydrocarbons, halon, and others. This modification affects the thermal radiation balance between earth, sun and space, resulting in a decrease of radiation outflow and a slow rise in the earth`s steady state temperature. For this reason the solution to the problem is perceived as one of cleaning up the processes and effluents that are discharged into the environment. In this paper arguments are presented that suggest, that there is a far more serious cause for global warming that will manifest itself in the next two or three centuries; direct heating from the exponential growth of energy usage by humankind. Because this is a minor contributor to the global warming problem at present, it is overlooked or ignored. Energy use from the combustion of fuels and from the output of nuclear reactions eventually is manifest as warming of the surroundings. Thus, as energy is used at an ever increasing rate the consequent global warming also increases at an ever increasing rate. Eventually this rate will become equal to a few percent of solar radiation. When this happens the earth`s temperature will have risen by several degrees with catastrophic results. The trends in world energy use are reviewed and some mathematical models are presented to suggest future scenarios. These models can be used to predict when the global warming problem will become undeniably apparent, when it will become critical, and when it will become catastrophic.

  7. Real time sensor for therapeutic radiation delivery

    DOE Patents [OSTI]

    Bliss, Mary (West Richland, WA); Craig, Richard A. (West Richland, WA); Reeder, Paul L. (Richland, WA)

    1998-01-01T23:59:59.000Z

    The invention is a real time sensor for therapeutic radiation. A probe is placed in or near the patient that senses in real time the dose at the location of the probe. The strength of the dose is determined by either an insertion or an exit probe. The location is determined by a series of vertical and horizontal sensing elements that gives the operator a real time read out dose location relative to placement of the patient. The increased accuracy prevents serious tissue damage to the patient by preventing overdose or delivery of a dose to a wrong location within the body.

  8. Real time sensor for therapeutic radiation delivery

    DOE Patents [OSTI]

    Bliss, M.; Craig, R.A.; Reeder, P.L.

    1998-01-06T23:59:59.000Z

    The invention is a real time sensor for therapeutic radiation. A probe is placed in or near the patient that senses in real time the dose at the location of the probe. The strength of the dose is determined by either an insertion or an exit probe. The location is determined by a series of vertical and horizontal sensing elements that gives the operator a real time read out dose location relative to placement of the patient. The increased accuracy prevents serious tissue damage to the patient by preventing overdose or delivery of a dose to a wrong location within the body. 14 figs.

  9. Custom Device for Low-Dose Gamma Irradiation of Biological Samples

    E-Print Network [OSTI]

    Bi, Ruoming

    2012-02-14T23:59:59.000Z

    , the structural material is efficient to absorb most of the cosmic-ray energy and reduce the interior dose rate to below 1.2 mGy per day. However, the biological effects of prolonged exposure to low-dose radiation are not well understood. The purpose...

  10. A revised dosimetric model for calculation of electron dose in the small intestine

    E-Print Network [OSTI]

    Bhuiyan, Md. Nasir Uddin

    2000-01-01T23:59:59.000Z

    1. Summary of descriptive parameters characterizing the adult human SI. . . . . . 59 Table 2. Elemental composition of soft tissue 66 Table 3. Ratio (v) of electron absorbed dose at mean depth of stem cells (sensitive cells) to absorbed dose... LIST OF ACRONYMS GI ICRP DLI Absorbed Fraction Gastrointestinal International Commission on Radiological Protection Dist' Large Intestine Medical Internal Radiation Dose SEE SI ST PLI Specific Absorbed Fraction Specific Effective Energy...

  11. Ground-water contribution to dose from past Hanford Operations. Hanford Environmental Dose Reconstruction Project

    SciTech Connect (OSTI)

    Freshley, M.D.; Thorne, P.D.

    1992-08-01T23:59:59.000Z

    The Hanford Environmental Dose Reconstruction (HEDR) 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 migrating 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 next to the Columbia River downstream of Hanford that draw some or all of their water from the river (riparian wells); and (4) through atmospheric deposition resulting in contamination of a small watershed that, in turn, results in contamination of a shallow well or spring by transport in the ground water. These four pathways make up the ``ground-water pathway,`` which is the subject of this study. Assessment of the ground-water pathway was performed by (1) reviewing the existing extensive literature on ground water and ground-water monitoring at Hanford and (2) performing calculations to estimate radionuclide concentrations where no monitoring data were collected. Radiation doses that would result from exposure to these radionuclides were calculated.

  12. Conditioning of the 4 Curies Radium-226 Sealed Radiation Source in Thailand

    SciTech Connect (OSTI)

    Punnachaiya, M.; Sawangsri, T.; Wanabongse, P.; Pruantonsai, P.; Nunjan, P.; Phattanasub, A.; Ya-Anant, N.; Thiangtrongjit, S. [Office of Atoms for Peace (OAP), Vibhavadi Rangsit Road, Chatuchak District, Bangkok 10900 (Thailand)

    2006-07-01T23:59:59.000Z

    This paper describes the conditioning of the 4 curies Radium-226 (Ra-226) sealed radiation source using as a teletherapy unit for cancer treatment in Thailand. The conditioning was under the International Atomic Energy Agency (IAEA) supervision and budgetary supports, comprised of 6 operational steps: the surface dose rate and actual dimension of radium unit measurements, the appropriate lead shielding design with IAEA approval, confirmation of radioactive contamination before conditioning (smear test and radon gas leakage test), transfer of radium source unit into the designed shielding, confirmation of radioactive contamination and dose rate measurement after conditioning, and transportation of Ra-226 conditioning waste package to OAP interim waste storage. The Ra-226 unit was taken out of OAP temporary waste storage for the surface dose rate and the actual dimension measurements behind the 12 inches thick heavy concrete shielding. The maximum measured surface dose rate was 70 R/hr. The special lead container was designed according to its surface dose rate along the source unit which the maximum permissible dose limit for surface dose rate of waste package after conditioning at 2 mSv/hr was applied. The IAEA approved container had total weight of 2.4 ton. After the confirmation of radioactive contamination, Ra-226 source unit was transferred and loaded in the designed lead shielding within 2 minutes. The results of smear test before and after conditioning including radon gas leakage test revealed that there was no radioactive contamination. After conditioning, the surface dose rate measured on the top, bottom were 15,10 mR/hr and varied from 6 - 50 mR/hr around lead container. The Ra-226 conditioning waste package was safely transported to store in OAP interim waste storage. Total working time including the time consumed for radon gas leakage test was 3.5 hours. The total radiation dose received by 16 operators, were ranged from 1 - 69.84 {mu}Sv and the operational team completed the conditioning safely within the effective dose limit for occupational exposure of 50 mSv/year (200 {mu}Sv/day). (authors)

  13. Standardized radiological dose evaluations

    SciTech Connect (OSTI)

    Peterson, V.L.; Stahlnecker, E.

    1996-05-01T23:59:59.000Z

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

  14. Danger radiations

    ScienceCinema (OSTI)

    None

    2011-04-25T23:59:59.000Z

    Le conférencier Mons.Hofert parle des dangers et risques des radiations, le contrôle des zones et les précautions à prendre ( p.ex. film badge), comment mesurer les radiations etc.

  15. Basis for radiation protection of the nuclear worker

    SciTech Connect (OSTI)

    Guevara, F.A.

    1982-01-01T23:59:59.000Z

    A description is given of the standards for protection of persons who work in areas that have a potential for radiation exposure. A review is given of the units of radiation exposure and dose equivalent and of the value of the maximum permissible dose limits for occupational exposure. Federal Regulations and Regulatory Guides for radiation protection are discussed. Average occupational equivalent doses experienced in several operations typical of the United States Nuclear Industry are presented and shown to be significantly lower than the maximum permissible. The concept of maintaining radiation doses to As-Low-As-Reasonably-Achievable is discussed and the practice of imposing engineering and administrative controls to provide effective radiation protection for the nuclear worker is described.

  16. Light beam range finder

    DOE Patents [OSTI]

    McEwan, Thomas E. (Livermore, CA)

    1998-01-01T23:59:59.000Z

    A "laser tape measure" for measuring distance which includes a transmitter such as a laser diode which transmits a sequence of electromagnetic pulses in response to a transmit timing signal. A receiver samples reflections from objects within the field of the sequence of visible electromagnetic pulses with controlled timing, in response to a receive timing signal. The receiver generates a sample signal in response to the samples which indicates distance to the object causing the reflections. The timing circuit supplies the transmit timing signal to the transmitter and supplies the receive timing signal to the receiver. The receive timing signal causes the receiver to sample the reflection such that the time between transmission of pulses in the sequence in sampling by the receiver sweeps over a range of delays. The transmit timing signal causes the transmitter to transmit the sequence of electromagnetic pulses at a pulse repetition rate, and the received timing signal sweeps over the range of delays in a sweep cycle such that reflections are sampled at the pulse repetition rate and with different delays in the range of delays, such that the sample signal represents received reflections in equivalent time. The receiver according to one aspect of the invention includes an avalanche photodiode and a sampling gate coupled to the photodiode which is responsive to the received timing signal. The transmitter includes a laser diode which supplies a sequence of visible electromagnetic pulses. A bright spot projected on to the target clearly indicates the point that is being measured, and the user can read the range to that point with precision of better than 0.1%.

  17. Light beam range finder

    DOE Patents [OSTI]

    McEwan, T.E.

    1998-06-16T23:59:59.000Z

    A ``laser tape measure`` for measuring distance is disclosed which includes a transmitter such as a laser diode which transmits a sequence of electromagnetic pulses in response to a transmit timing signal. A receiver samples reflections from objects within the field of the sequence of visible electromagnetic pulses with controlled timing, in response to a receive timing signal. The receiver generates a sample signal in response to the samples which indicates distance to the object causing the reflections. The timing circuit supplies the transmit timing signal to the transmitter and supplies the receive timing signal to the receiver. The receive timing signal causes the receiver to sample the reflection such that the time between transmission of pulses in the sequence in sampling by the receiver sweeps over a range of delays. The transmit timing signal causes the transmitter to transmit the sequence of electromagnetic pulses at a pulse repetition rate, and the received timing signal sweeps over the range of delays in a sweep cycle such that reflections are sampled at the pulse repetition rate and with different delays in the range of delays, such that the sample signal represents received reflections in equivalent time. The receiver according to one aspect of the invention includes an avalanche photodiode and a sampling gate coupled to the photodiode which is responsive to the received timing signal. The transmitter includes a laser diode which supplies a sequence of visible electromagnetic pulses. A bright spot projected on to the target clearly indicates the point that is being measured, and the user can read the range to that point with precision of better than 0.1%. 7 figs.

  18. Efficient wireless non-radiative mid-range energy transfer

    E-Print Network [OSTI]

    Soljaèiæ, Marin

    -wire grid was deployed, seri- ous interest and effort was devoted (most notably by Nikola Tesla [1]) towards storage) justifies revisiting investigation of this issue. Today, we face a different challenge than Tesla

  19. Establishment and validation of a method for multi-dose irradiation of cells in 96-well microplates

    SciTech Connect (OSTI)

    Abatzoglou, Ioannis; Zois, Christos E.; Pouliliou, Stamatia [Department of Radiotherapy/Oncology, Radiobiology and Radiopathology Unit, Democritus University of Thrace, Alexandroupolis (Greece)] [Department of Radiotherapy/Oncology, Radiobiology and Radiopathology Unit, Democritus University of Thrace, Alexandroupolis (Greece); Koukourakis, Michael I., E-mail: targ@her.forthnet.gr [Department of Radiotherapy/Oncology, Radiobiology and Radiopathology Unit, Democritus University of Thrace, Alexandroupolis (Greece)

    2013-02-15T23:59:59.000Z

    Highlights: ? We established a method for multi-dose irradiation of cell cultures within a 96-well plate. ? Equations to adjust to preferable dose levels are produced and provided. ? Up to eight different dose levels can be tested in one microplate. ? This method results in fast and reliable estimation of radiation dose–response curves. -- Abstract: Microplates are useful tools in chemistry, biotechnology and molecular biology. In radiobiology research, these can be also applied to assess the effect of a certain radiation dose delivered to the whole microplate, to test radio-sensitivity, radio-sensitization or radio-protection. Whether different radiation doses can be accurately applied to a single 96-well plate to further facilitate and accelerated research by one hand and spare funds on the other, is a question dealt in the current paper. Following repeated ion-chamber, TLD and radiotherapy planning dosimetry we established a method for multi-dose irradiation of cell cultures within a 96-well plate, which allows an accurate delivery of desired doses in sequential columns of the microplate. Up to eight different dose levels can be tested in one microplate. This method results in fast and reliable estimation of radiation dose–response curves.

  20. Health Impacts from Acute Radiation Exposure

    SciTech Connect (OSTI)

    Strom, Daniel J.

    2003-09-30T23:59:59.000Z

    Absorbed doses above1-2 Gy (100-200 rads) received over a period of a day or less lead to one or another of the acute radiation syndromes. These are the hematopoietic syndrome, the gastrointestinal (GI) syndrome, the cerebrovascular (CV) syndrome, the pulmonary syndrome, or the cutaneous syndrome. The dose that will kill about 50% of the exposed people within 60 days with minimal medical care, LD50-60, is around 4.5 Gy (450 rads) of low-LET radiation measured free in air. The GI syndrome may not be fatal with supportive medical care and growth factors below about 10 Gy (1000 rads), but above this is likely to be fatal. Pulmonary and cutaneous syndromes may or may not be fatal, depending on many factors. The CV syndrome is invariably fatal. Lower acute doses, or protracted doses delivered over days or weeks, may lead to many other health outcomes than death. These include loss of pregnancy, cataract, impaired fertility or temporary or permanent sterility, hair loss, skin ulceration, local tissue necrosis, developmental abnormalities including mental and growth retardation in persons irradiated as children or fetuses, radiation dermatitis, and other symptoms listed in Table 2 on page 12. Children of parents irradiated prior to conception may experience heritable ill-health, that is, genetic changes from their parents. These effects are less strongly expressed than previously thought. Populations irradiated to high doses at high dose rates have increased risk of cancer incidence and mortality, taken as about 10-20% incidence and perhaps 5-10% mortality per sievert of effective dose of any radiation or per gray of whole-body absorbed dose low-LET radiation. Cancer risks for non-uniform irradiation will be less.

  1. Monte Carlo simulations of solid walled proportional counters with different site size for HZE radiation 

    E-Print Network [OSTI]

    Wang, Xudong

    2009-05-15T23:59:59.000Z

    Characterizing high z high energy (HZE) particles in cosmic radiation is of importance for the study of the equivalent dose to astronauts. Low pressure, tissue equivalent proportional counters (TEPC) are routinely used to evaluate radiation...

  2. Monte Carlo simulations of solid walled proportional counters with different site size for HZE radiation

    E-Print Network [OSTI]

    Wang, Xudong

    2009-05-15T23:59:59.000Z

    Characterizing high z high energy (HZE) particles in cosmic radiation is of importance for the study of the equivalent dose to astronauts. Low pressure, tissue equivalent proportional counters (TEPC) are routinely used to evaluate radiation...

  3. ORISE: Dose modeling and assessments

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

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

  4. Parameterization of solar flare dose 

    E-Print Network [OSTI]

    Lamarche, Anne Helene

    1995-01-01T23:59:59.000Z

    A critical aspect of missions to the Moon or Mars is the safety and health of the crew. Radiation in space is a hazard for astronauts, especially high-energy radiation following certain types of solar flares. A solar flare ...

  5. 74Exploring Nuclear Decay and Radiation Dose The devastating earthquake

    E-Print Network [OSTI]

    and fall to the ground, contaminating the soil. Cesium-137 has a half-life of 30 years, while Iodine-131 in the vented gases are Cesium-137 and Iodine-131. These will become incorporated into atmospheric dust grains

  6. ambient radiation dose: Topics by E-print Network

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

    Vibration TestForced Vibration Test Seismic-B Building Bogazici University 12;Seismic Retrofitting Before Retrofit After Retrofit Dimension (cm ? cm mode in E-W 3 3.5 4...

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

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office511041cloth DocumentationProductsAlternative FuelsSanta3 Table 3.EnergyAug412Electricity

  8. Neutron range spectrometer

    DOE Patents [OSTI]

    Manglos, S.H.

    1988-03-10T23:59:59.000Z

    A neutron range spectrometer and method for determining the neutron energy spectrum of a neutron emitting source are disclosed. Neutrons from the source are colliminated along a collimation axis and a position sensitive neutron counter is disposed in the path of the collimated neutron beam. The counter determines positions along the collimation axis of interactions between the neutrons in the neutron beam and a neutron-absorbing material in the counter. From the interaction positions, a computer analyzes the data and determines the neutron energy spectrum of the neutron beam. The counter is preferably shielded and a suitable neutron-absorbing material is He-3. 1 fig.

  9. SYNCHROTRON RADIATION SOURCES

    SciTech Connect (OSTI)

    HULBERT,S.L.; WILLIAMS,G.P.

    1998-07-01T23:59:59.000Z

    Synchrotron radiation is a very bright, broadband, polarized, pulsed source of light extending from the infrared to the x-ray region. It is an extremely important source of Vacuum Ultraviolet radiation. Brightness is defined as flux per unit area per unit solid angle and is normally a more important quantity than flux alone particularly in throughput limited applications which include those in which monochromators are used. It is well known from classical theory of electricity and magnetism that accelerating charges emit electromagnetic radiation. In the case of synchrotron radiation, relativistic electrons are accelerated in a circular orbit and emit electromagnetic radiation in a broad spectral range. The visible portion of this spectrum was first observed on April 24, 1947 at General Electric's Schenectady facility by Floyd Haber, a machinist working with the synchrotron team, although the first theoretical predictions were by Lienard in the latter part of the 1800's. An excellent early history with references was presented by Blewett and a history covering the development of the utilization of synchrotron radiation was presented by Hartman. Synchrotron radiation covers the entire electromagnetic spectrum from the infrared region through the visible, ultraviolet, and into the x-ray region up to energies of many 10's of kilovolts. If the charged particles are of low mass, such as electrons, and if they are traveling relativistically, the emitted radiation is very intense and highly collimated, with opening angles of the order of 1 milliradian. In electron storage rings there are three possible sources of synchrotron radiation; dipole (bending) magnets; wigglers, which act like a sequence of bending magnets with alternating polarities; and undulators, which are also multi-period alternating magnet systems but in which the beam deflections are small resulting in coherent interference of the emitted light.

  10. Depth absorbed dose and LET distributions of therapeutic {sup 1}H, {sup 4}He, {sup 7}Li, and {sup 12}C beams

    SciTech Connect (OSTI)

    Kempe, Johanna; Gudowska, Irena; Brahme, Anders [Division of Medical Radiation Physics, Department of Oncology-Pathology, Karolinska Institutet and Stockholm University, Box 260, SE-171 76 Stockholm (Sweden)

    2007-01-15T23:59:59.000Z

    The depth absorbed dose and LET (linear energy transfer) distribution of different ions of clinical interest such as {sup 1}H, {sup 4}He, {sup 7}Li, and {sup 12}C ions have been investigated using the Monte Carlo code SHIELD-HIT. The energies of the projectiles correspond to ranges in water and soft tissue of approximately 260 mm. The depth dose distributions of the primary particles and their secondaries have been calculated and separated with regard to their low and high LET components. A LET value below 10 eV/nm can generally be regarded as low LET and sparsely ionizing like electrons and photons. The high LET region may be assumed to start at 20 eV/nm where on average two double-strand breaks can be formed when crossing the periphery of a nucleosome, even though strictly speaking the LET limits are not sharp and ought to vary with the charge and mass of the ion. At the Bragg peak of a monoenergetic high energy proton beam, less than 3% of the total absorbed dose is comprised of high LET components above 20 eV/nm. The high LET contribution to the total absorbed dose in the Bragg peak is significantly larger with increasing ion charge as a natural result of higher stopping power and lower range straggling. The fact that the range straggling and multiple scattering are reduced by half from hydrogen to helium increases the possibility to accurately deposit only the high LET component in the tumor with negligible dose to organs at risk. Therefore, the lateral penumbra is significantly improved and the higher dose gradients of {sup 7}Li and {sup 12}C ions both longitudinally and laterally will be of major advantage in biological optimized radiation therapy. With increasing charge of the ion, the high LET absorbed dose in the beam entrance and the plateau regions where healthy normal tissues are generally located is also increased. The dose distribution of the high LET components in the {sup 7}Li beam is only located around the Bragg peak, characterized by a Gaussian-type distribution. Furthermore, the secondary particles produced by high energy {sup 7}Li ions in tissuelike media have mainly low LET character both in front of and beyond the Bragg peak.

  11. Meeting Report--NASA Radiation Biomarker Workshop

    SciTech Connect (OSTI)

    Straume, Tore; Amundson, Sally A,; Blakely, William F.; Burns, Frederic J.; Chen, Allen; Dainiak, Nicholas; Franklin, Stephen; Leary, Julie A.; Loftus, David J.; Morgan, William F.; Pellmar, Terry C.; Stolc, Viktor; Turteltaub, Kenneth W.; Vaughan, Andrew T.; Vijayakumar, Srinivasan; Wyrobek, Andrew J.

    2008-05-01T23:59:59.000Z

    A summary is provided of presentations and discussions from the NASA Radiation Biomarker Workshop held September 27-28, 2007, at NASA Ames Research Center in Mountain View, California. Invited speakers were distinguished scientists representing key sectors of the radiation research community. Speakers addressed recent developments in the biomarker and biotechnology fields that may provide new opportunities for health-related assessment of radiation-exposed individuals, including for long-duration space travel. Topics discussed include the space radiation environment, biomarkers of radiation sensitivity and individual susceptibility, molecular signatures of low-dose responses, multivariate analysis of gene expression, biomarkers in biodefense, biomarkers in radiation oncology, biomarkers and triage following large-scale radiological incidents, integrated and multiple biomarker approaches, advances in whole-genome tiling arrays, advances in mass-spectrometry proteomics, radiation biodosimetry for estimation of cancer risk in a rat skin model, and confounding factors. Summary conclusions are provided at the end of the report.

  12. RADIATION RESEARCH 156, 594597 (2001) 0033-7587/01 $5.00

    E-Print Network [OSTI]

    Brenner, David Jonathan

    2001-01-01T23:59:59.000Z

    594 RADIATION RESEARCH 156, 594­597 (2001) 0033-7587/01 $5.00 2001 by Radiation Research Society Doses. Radiat. Res. 156, 594­597 (2001). The patterns of DSBs induced in the genome are different for sparsely and densely ionizing radiations: In the former case, the patterns are well described by a random

  13. RADIATION RESEARCH 151, 225-229 (1999) 0033-7587199 $5.00

    E-Print Network [OSTI]

    Brenner, David Jonathan

    1999-01-01T23:59:59.000Z

    Society INTRODUCTION One of the most important issues in radiation protection is the effect of doseRADIATION RESEARCH 151, 225-229 (1999) 0033-7587199 $5.00 0 1999 by Radiation Research Society of Breast Cancer Induced by Low-LET Radiation? D. J. Brenner Centerfor Radiological Research, Columbia

  14. Clinical Response of Pelvic and Para-aortic Lymphadenopathy to a Radiation Boost in the Definitive Management of Locally Advanced Cervical Cancer

    SciTech Connect (OSTI)

    Rash, Dominique L. [Department of Radiation Oncology, University of California Davis Medical Center, Sacramento, California (United States); Lee, Yongsook C. [Department of Radiation Oncology, University of Kansas School of Medicine, Kansas City, Kansas (United States); Kashefi, Amir [Division of Nuclear Medicine, Department of Radiology, University of California Davis Medical Center, Sacramento, California (United States); Durbin-Johnson, Blythe [Division of Biostatistics, Department of Public Health Sciences, University of California Davis School of Medicine, Sacramento, California (United States); Mathai, Mathew; Valicenti, Richard [Department of Radiation Oncology, University of California Davis Medical Center, Sacramento, California (United States); Mayadev, Jyoti S., E-mail: jyoti.mayadev@ucdmc.ucdavis.edu [Department of Radiation Oncology, University of California Davis Medical Center, Sacramento, California (United States)

    2013-10-01T23:59:59.000Z

    Purpose: Optimal treatment with radiation for metastatic lymphadenopathy in locally advanced cervical cancer remains controversial. We investigated the clinical dose response threshold for pelvic and para-aortic lymph node boost using radiographic imaging and clinical outcomes. Methods and Materials: Between 2007 and 2011, 68 patients were treated for locally advanced cervical cancer; 40 patients had clinically involved pelvic and/or para-aortic lymph nodes. Computed tomography (CT) or 18F-labeled fluorodeoxyglucose-positron emission tomography scans obtained pre- and postchemoradiation for 18 patients were reviewed to assess therapeutic radiographic response of individual lymph nodes. External beam boost doses to involved nodes were compared to treatment response, assessed by change in size of lymph nodes by short axis and change in standard uptake value (SUV). Patterns of failure, time to recurrence, overall survival (OS), and disease-free survival (DFS) were determined. Results: Sixty-four lymph nodes suspicious for metastatic involvement were identified. Radiation boost doses ranged from 0 to 15 Gy, with a mean total dose of 52.3 Gy. Pelvic lymph nodes were treated with a slightly higher dose than para-aortic lymph nodes: mean 55.3 Gy versus 51.7 Gy, respectively. There was no correlation between dose delivered and change in size of lymph nodes along the short axis. All lymph nodes underwent a decrease in SUV with a complete resolution of abnormal uptake observed in 68%. Decrease in SUV was significantly greater for lymph nodes treated with ?54 Gy compared to those treated with <54 Gy (P=.006). Median follow-up was 18.7 months. At 2 years, OS and DFS for the entire cohort were 78% and 50%, respectively. Locoregional control at 2 years was 84%. Conclusions: A biologic response, as measured by the change in SUV for metastatic lymph nodes, was observed at a dose threshold of 54 Gy. We recommend that involved lymph nodes be treated to this minimum dose.

  15. A hybrid electron and photon IMRT planning technique that lowers normal tissue integral patient dose using standard hardware

    SciTech Connect (OSTI)

    Rosca, Florin [Department of Radiation Oncology, Massachusetts General Hospital, Danvers, Massachusetts 01923 (United States)

    2012-06-15T23:59:59.000Z

    Purpose: To present a mixed electron and photon IMRT planning technique using electron beams with an energy range of 6-22 MeV and standard hardware that minimizes integral dose to patients for targets as deep as 7.5 cm. Methods: Ten brain cases, two lung, a thyroid, an abdominal, and a parotid case were planned using two planning techniques: a photon-only IMRT (IMRT) versus a mixed modality treatment (E + IMRT) that includes an enface electron beam and a photon IMRT portion that ensures a uniform target coverage. The electron beam is delivered using a regular cutout placed in an electron cone. The electron energy was chosen to provide a good trade-off between minimizing integral dose and generating a uniform, deliverable plan. The authors choose electron energies that cover the deepest part of PTV with the 65%-70% isodose line. The normal tissue integral dose, the dose for ring structures around the PTV, and the volumes of the 75%, 50%, and 25% isosurfaces were used to compare the dose distributions generated by the two planning techniques. Results: The normal tissue integral dose was lowered by about 20% by the E + IMRT plans compared to the photon-only IMRT ones for most studied cases. With the exception of lungs, the dose reduction associated to the E + IMRT plans was more pronounced further away from the target. The average dose ratio delivered to the 0-2 cm and the 2-4 cm ring structures for brain patients for the two planning techniques were 89.6% and 70.8%, respectively. The enhanced dose sparing away from the target for the brain patients can also be observed in the ratio of the 75%, 50%, and 25% isodose line volumes for the two techniques, which decreases from 85.5% to 72.6% and further to 65.1%, respectively. For lungs, the lateral electron beams used in the E + IMRT plans were perpendicular to the mostly anterior/posterior photon beams, generating much more conformal plans. Conclusions: The authors proved that even using the existing electron delivery hardware, a mixed electron/photon planning technique (E + IMRT) can decrease the normal tissue integral dose compared to a photon-only IMRT plan. Different planning approaches can be enabled by the use of an electron beam directed toward organs at risk distal to the target, which are still spared due the rapid dose fall-off of the electron beam. Examples of such cases are the lateral electron beams in the thoracic region that do not irradiate the heart and contralateral lung, electron beams pointed toward kidneys in the abdominal region, or beams treating brain lesions pointed toward the brainstem or optical apparatus. For brain, electron vertex beams can also be used without irradiating the whole body. Since radiation retreatments become more and more common, minimizing the normal tissue integral dose and the dose delivered to tissues surrounding the target, as enabled by E + IMRT type techniques, should receive more attention.

  16. Range of Glaciers: The Exploration of the Northern Cascade Range

    E-Print Network [OSTI]

    Hook, Robert D.

    2006-01-01T23:59:59.000Z

    Review: Range of Glaciers: The Exploration of the NorthernUSA Fred Beckey. Range of Glaciers: The Exploration of thewill find that Range of Glaciers is a must read. The book

  17. Population exposure dose reconstruction for the Urals Region

    SciTech Connect (OSTI)

    Degteva, M.O.; Kozheurov, V.P.; Vorobiova, M.I.; Burmistrov, D.S. [Urals Research Center for Radiation Medicine, Chelyabinsk (Russian Federation); Khokhryakov, V.V. [Mayak Production Assn., Ozyorsk (Russian Federation); Suslova, K.G. [Moscow Biophysics Inst., Ozyorsk (Russian Federation); Anspaugh, L.R. [Lawrence Livermore National Lab., CA (United States); Napier, B.A. [Pacific Northwest Lab., Richland, WA (United States); Bouville, A. [National Cancer Inst., Bethesda, MD (United States)

    1996-06-01T23:59:59.000Z

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

  18. Parameters used in the environmental pathways and radiological dose modules (DESCARTES, CIDER, and CRD codes) of the Hanford Environmental Dose Reconstruction Integrated Codes (HEDRIC)

    SciTech Connect (OSTI)

    Snyder, S.F.; Farris, W.T.; Napier, B.A.; Ikenberry, T.A.; Gilbert, R.O.

    1994-05-01T23:59:59.000Z

    This letter report is a description of work performed for the Hanford Environmental Dose Reconstruction (HEDR) Project. The HEDR Project was established to estimate the radiation doses to individuals resulting from releases of radionuclides from the Hanford Site during the period of 1944 to 1992. This work is being done by staff at Battelle, Pacific Northwest Laboratories under a contract with the Centers for Disease Control and Prevention with technical direction provided by an independent Technical Steering Panel (TSP).

  19. alpha particles radiative: Topics by E-print Network

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

    rate includes a constant term and a linear term of radiation dose, implying that the damage to some cell nuclei has a time accumulating effect. This model ... Liu, Longjian...

  20. Estimation of food consumption. Hanford Environmental Dose Reconstruction Project

    SciTech Connect (OSTI)

    Callaway, J.M. Jr.

    1992-04-01T23:59:59.000Z

    The research reported in this document was conducted as a part of the Hanford Environmental Dose Reconstruction (HEDR) Project. The objective of the HEDR Project is to estimate the radiation doses that people could have received from operations at the Hanford Site. Information required to estimate these doses includes estimates of the amounts of potentially contaminated foods that individuals in the region consumed during the study period. In that general framework, the objective of the Food Consumption Task was to develop a capability to provide information about the parameters of the distribution(s) of daily food consumption for representative groups in the population for selected years during the study period. This report describes the methods and data used to estimate food consumption and presents the results developed for Phase I of the HEDR Project.

  1. Enhanced radiation detectors using luminescent materials

    DOE Patents [OSTI]

    Vardeny, Zeev V. (Holladay, UT); Jeglinski, Stefan A. (Durham, NC); Lane, Paul A. (Sheffield, GB)

    2001-01-01T23:59:59.000Z

    A radiation detecting device comprising a radiation sensing element, and a layer of luminescent material to expand the range of wavelengths over which the sensing element can efficiently detect radiation. The luminescent material being selected to absorb radiation at selected wavelengths, causing the luminescent material to luminesce, and the luminescent radiation being detected by the sensing element. Radiation sensing elements include photodiodes (singly and in arrays), CCD arrays, IR detectors and photomultiplier tubes. Luminescent materials include polymers, oligomers, copolymers and porphyrines, Luminescent layers include thin films, thicker layers, and liquid polymers.

  2. Possible options for reducing occupational dose from the TMI-2 basement

    SciTech Connect (OSTI)

    Munson, L. F. [Pacific Northwest Lab., Richland, WA (United States); Harty, R. [Pacific Northwest Lab., Richland, WA (United States)

    1985-11-01T23:59:59.000Z

    The major sources of exposure in the basement include the enclosed stairwell/elevator shaft structure, water and sludge in the elevator shaft, cast concrete walls, concrete floor slab, water and sludge on the floor, and activity in the paint and loose surface contamination. The sources were identified using data obtained by the utility from water processing, water and solid samples, remote video inspections and radiation monitoring with a robot, and strings of thermoluminescent dosimeters lowered from upper elevations. The area dose rates in the basement range from approximately 4 R/hr (in the NE quadrant) to over 1100 R/hr (near the enclosed stairwell/elevator shaft structure). It is estimated that the basement contains between 11,000 and 21,000 curies of /sup 137/Cs. Specific decontamination and cleanup techniques are discussed. These techniques include flushing with water, high-pressure water blasting, leaching, scabbling and chemical cleaning. The applicability of these techniques to the major sources of radiation are discussed, and possible approaches and work sequences for basement cleanup are given.

  3. INTEGRATED CODES FOR ESTIMATING ENVIRONMENTAL ACCUMULATION ANd INDIVIDUAL DOSE FROM PAST HANFORD ATMOSPHERIC RELEASES Hanford Environmental Dose Reconstruction Project

    SciTech Connect (OSTI)

    Ikenberry, T. A.; Burnett, R. A.; Napier, B. A.; Reitz, N. A.; Shipler, D. B.

    1992-02-01T23:59:59.000Z

    Preliminary radiation doses were estimated and reported during Phase I of the Hanford Environmental Dose Reconstruction (HEDR) Project. As the project has progressed, additional information regarding the magnitude and timing of past radioactive releases has been developed, and the general scope of the required calculations has been enhanced. The overall HEDR computational model for computing doses attributable to atmospheric releases from Hanford Site operations is called HEDRIC (Hanford Environmental Dose Reconstruction Integrated Codes). It consists of four interrelated models: source term, atmospheric transport, environmental accumulation, and individual dose. The source term and atmospheric transport models are documented elsewhere. This report describes the initial implementation of the design specifications for the environmental accumulation model and computer code, called DESCARTES (Dynamic EStimates of Concentrations and Accumulated Radionuclides in Terrestrial Environments), and the individual dose model and computer code, called CIDER (Calculation of Individual Doses from Environmental Radionuclides). The computations required of these models and the design specifications for their codes were documented in Napier et al. (1992). Revisions to the original specifications and the basis for modeling decisions are explained. This report is not the final code documentation but gives the status of the model and code development to date. Final code documentation is scheduled to be completed in FY 1994 following additional code upgrades and refinements. The user's guide included in this report describes the operation of the environmental accumulation and individual dose codes and associated pre- and post-processor programs. A programmer's guide describes the logical structure of the programs and their input and output files.

  4. On the Sensitivity of ?/? Prediction to Dose Calculation Methodology in Prostate Brachytherapy

    SciTech Connect (OSTI)

    Afsharpour, Hossein [Centre de Recherche sur le Cancer, Université Laval and Département de Radio-Oncologie, Centre Hospitalier Universitaire de Québec, Québec, QC (Canada); Centre Intégré de Cancérologie de la Montérégie, Hôpital Charles-LeMoyne, Greenfield Park, QC (Canada); Walsh, Sean [Department of Radiation Oncology Maastricht Radiation Oncology (MAASTRO), GROW, University Hospital Maastricht, Maastricht (Netherlands); Gray Institute for Radiation Oncology and Biology, The University of Oxford, The United Kingdom (United Kingdom); Collins Fekete, Charles-Antoine; Vigneault, Eric [Centre de Recherche sur le Cancer, Université Laval and Département de Radio-Oncologie, Centre Hospitalier Universitaire de Québec, Québec, QC (Canada); Verhaegen, Frank [Department of Radiation Oncology Maastricht Radiation Oncology (MAASTRO), GROW, University Hospital Maastricht, Maastricht (Netherlands); Medical Physics Unit, Department of Oncology, McGill University, Montréal, Québec (Canada); Beaulieu, Luc, E-mail: Luc.Beaulieu@phy.ulaval.ca [Centre de Recherche sur le Cancer, Université Laval and Département de Radio-Oncologie, Centre Hospitalier Universitaire de Québec, Québec, QC (Canada)

    2014-02-01T23:59:59.000Z

    Purpose: To study the relationship between the accuracy of the dose calculation in brachytherapy and the estimations of the radiosensitivity parameter, ?/?, for prostate cancer. Methods and Materials: In this study, Monte Carlo methods and more specifically the code ALGEBRA was used to produce accurate dose calculations in the case of prostate brachytherapy. Equivalent uniform biologically effective dose was calculated for these dose distributions and was used in an iso-effectiveness relationship with external beam radiation therapy. Results: By considering different levels of detail in the calculations, the estimation for the ?/? parameter varied from 1.9 to 6.3 Gy, compared with a value of 3.0 Gy suggested by the American Association of Physicists in Medicine Task Group 137. Conclusions: Large variations of the ?/? show the sensitivity of this parameter to dose calculation modality. The use of accurate dose calculation engines is critical for better evaluating the biological outcomes of treatments.

  5. Radiation detector

    DOE Patents [OSTI]

    Fultz, Brent T. (Berkeley, CA)

    1983-01-01T23:59:59.000Z

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

  6. Radiation detector

    DOE Patents [OSTI]

    Fultz, B.T.

    1980-12-05T23:59:59.000Z

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

  7. LFS-3 - new radiation hard scintillator for electromagnetic calorimeters

    E-Print Network [OSTI]

    Kozlov, V A; Zavartsev, Yu D; Zavertyaev, M V; Zerrouk, A F

    2009-01-01T23:59:59.000Z

    Radiation damage of new heavy LFS-3 scintillating crystals has been studied using powerful $^{60}Co$ source at the dose rate of 4 Krad/min. No deterioration in optical transmission of LFS-3 crystals was observed after irradiation with the dose of 23 Mrad.

  8. Technical basis for dose reconstruction

    SciTech Connect (OSTI)

    Anspaugh, L.R.

    1996-01-31T23:59:59.000Z

    The purpose of this paper is to consider two general topics: technical considerations of why dose-reconstruction studies should or should not be performed and methods of dose reconstruction. The first topic is of general and growing interest as the number of dose-reconstruction studies increases, and one asks the question whether it is necessary to perform a dose reconstruction for virtually every site at which, for example, the Department of Energy (DOE) has operated a nuclear-related facility. And there is the broader question of how one might logically draw the line at performing or not performing dose-reconstruction (radiological and chemical) studies for virtually every industrial complex in the entire country. The second question is also of general interest. There is no single correct way to perform a dose-reconstruction study, and it is important not to follow blindly a single method to the point that cheaper, faster, more accurate, and more transparent methods might not be developed and applied.

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

    SciTech Connect (OSTI)

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

    2013-12-01T23:59:59.000Z

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

  10. Spallation Neutron Source Radiation Shielding Issues

    SciTech Connect (OSTI)

    Azmy, Y.Y.; Barnes, J.M.; Drischler, J.D.; Johnston, J.O.; Lillie, R.A.; McNeilly, G.S.; Santoro, R.T.

    1999-11-14T23:59:59.000Z

    This paper summarizes results of Spallation Neutron Source calculations to estimate radiation hazards and shielding requirements for activated Mercury, target components, target cooling water, and {sup 7}Be plateout. Dose rates in the accelerator tunnel from activation of magnets and concrete were investigated. The impact of gaps and other streaming paths on the radiation environment inside the test cell during operation and after shutdown were also assessed.

  11. Intrarectal amifostine suspension may protect against acute proctitis during radiation therapy for prostate cancer: A pilot study

    SciTech Connect (OSTI)

    Singh, Anurag K. [Radiation Oncology Branch, National Cancer Institute, National Institutes of Health, Department of Health and Human Services, Bethesda, MD (United States); Menard, Cynthia [Radiation Medicine Program, Princess Margaret Hospital, University Health Network, University of Toronto, Toronto, Ontario (Canada); Guion, Peter [Radiation Oncology Branch, National Cancer Institute, National Institutes of Health, Department of Health and Human Services, Bethesda, MD (United States)]. E-mail: guionp@mail.nih.gov; Simone, Nicole L. [Radiation Oncology Branch, National Cancer Institute, National Institutes of Health, Department of Health and Human Services, Bethesda, MD (United States); Smith, Sharon [Radiation Oncology Branch, National Cancer Institute, National Institutes of Health, Department of Health and Human Services, Bethesda, MD (United States); Crouse, Nancy Sears [Radiation Oncology Branch, National Cancer Institute, National Institutes of Health, Department of Health and Human Services, Bethesda, MD (United States); Godette, Denise J. [Radiation Oncology Branch, National Cancer Institute, National Institutes of Health, Department of Health and Human Services, Bethesda, MD (United States); Cooley-Zgela, Theresa; Sciuto, Linda C.; Camphausen, Kevin; Coleman, C. Norman [Radiation Oncology Branch, National Cancer Institute, National Institutes of Health, Department of Health and Human Services, Bethesda, MD (United States); Coleman, Jonathan; Pinto, Peter [Urologic Oncology Branch, National Cancer Institute, National Institutes of Health, Department of Health and Human Services, Bethesda, MD (United States); Albert, Paul S. [Biometric Research Branch, Division of Cancer Treatment and Diagnosis, National Cancer Institute, Bethesda, MD (United States)

    2006-07-15T23:59:59.000Z

    Purpose: Our goal was to test the ability of intrarectal amifostine to limit symptoms of radiation proctitis. Methods and Materials: The first 18 patients received 1 g of intrarectal amifostine suspension placed 30-45 min before each radiation treatment. The following 12 patients received 2 g of amifostine. Total dose prescribed ranged from 66 to 76 Gy. All patients were treated with three-dimensional conformal radiation therapy. The suspension remained intrarectal during treatment and was expelled after treatment. For gastrointestinal symptoms, during treatment and follow-up, all patients had a Radiation Therapy Oncology Group (RTOG) grade recorded. Results: Median follow-up was 18 months (range, 6-24 months). With 2 g vs. 1 g amifostine, there was a nearly significant decrease in RTOG Grade 2 acute rectal toxicity. Seven weeks after the start of radiation therapy, the incidence of Grade 2 toxicity was 33% in the 1-g group (6/18) compared with 0% (0/12) in the 2-g group (p = 0.06). No Grade 3 toxicity or greater occurred in this study. Conclusion: This trial suggests greater rectal radioprotection from acute effects with 2 g vs. 1 g amifostine suspension. Further studies should be conducted in populations at higher risk for developing symptomatic acute and late proctitis.

  12. Fan-less long range alpha detector

    DOE Patents [OSTI]

    MacArthur, D.W.; Bounds, J.A.

    1994-05-10T23:59:59.000Z

    A fan-less long range alpha detector is disclosed which operates by using an electrical field between a signal plane and the surface or substance to be monitored for air ions created by collisions with alpha radiation. Without a fan, the detector can operate without the possibility of spreading dust and potential contamination into the atmosphere. A guard plane between the signal plane and the electrically conductive enclosure and maintained at the same voltage as the signal plane, reduces leakage currents. The detector can easily monitor soil, or other solid or liquid surfaces. 2 figures.

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

    SciTech Connect (OSTI)

    Maldonado, Delis [Oak Ridge Institute for Science and Education, Oak Ridge, TN (United States). Independent Environmental Assessment and Verification Program

    2012-06-01T23:59:59.000Z

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

  14. Parameterization of solar flare dose

    E-Print Network [OSTI]

    Lamarche, Anne Helene

    1995-01-01T23:59:59.000Z

    A critical aspect of missions to the Moon or Mars is the safety and health of the crew. Radiation in space is a hazard for astronauts, especially high-energy radiation following certain types of solar flares. A solar flare event can be very...

  15. PRECEDENTS FOR AUTHORIZATION OF CONTENTS USING DOSE RATE MEASUREMENTS

    SciTech Connect (OSTI)

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

    2012-06-05T23:59:59.000Z

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

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

    E-Print Network [OSTI]

    Vu, An T. (An Thien)

    2011-01-01T23:59:59.000Z

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

  17. Integrated Molecular Analysis Indicates Undetectable Change in DNA Damage in Mice after Continuous Irradiation at ~ 400-fold Natural Background Radiation

    E-Print Network [OSTI]

    Olipitz, Werner

    Background: In the event of a nuclear accident, people are exposed to elevated levels of continuous low dose-rate radiation. Nevertheless, most of the literature describes the biological effects of acute radiation.

  18. Radiation-induced Genomic Instability and Radiation Sensitivity

    SciTech Connect (OSTI)

    Varnum, Susan M.; Sowa, Marianne B.; Kim, Grace J.; Morgan, William F.

    2013-01-19T23:59:59.000Z

    The obvious relationships between reactive oxygen and nitrogen species, mitochondrial dysfunction, inflammatory type responses and reactive chemokines and cytokines suggests a general stress response induced by ionizing radiation most likely leads to the non-targeted effects described after radiation exposure. We argue that true bystander effects do not occur in the radiation therapy clinic. But there is no question that effects outside the target volume do occur. These “out of field effects” are considered very low dose effects in the context of therapy. So what are the implications of non-targeted effects on radiation sensitivity? The primary goal of therapy is to eradicate the tumor. Given the genetic diversity of the human population, lifestyle and environment factors it is likely some combination of these will influence patient outcome. Non-targeted effects may contribute to a greater or lesser extent. But consider the potential situation involving a partial body exposure due to a radiation accident or radiological terrorism. Non-targeted effects suggest that the tissue at risk for demonstrating possible detrimental effects of radiation exposure might be greater than the volume actually irradiated.

  19. RADIATION SAFETY TRAINING MANUAL Radiation Safety Office

    E-Print Network [OSTI]

    Sibille, Etienne

    protection and the potential risks of ionizing radiation. Radiation Safety Office personnel provide.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 II. OVERVIEW OF REGULATIONS, PROTECTION STANDARDS, AND RADIATION SAFETY ORGANIZATION.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 V. BASIC RADIATION PROTECTION PRINCIPLES

  20. Serum Amyloid A as a Predictive Marker for Radiation Pneumonitis in Lung Cancer Patients

    SciTech Connect (OSTI)

    Wang, Yu-Shan [Department of Radiation Therapy and Oncology, Shin Kong Wu Ho-Su Memorial Hospital, Taipei, Taiwan (China) [Department of Radiation Therapy and Oncology, Shin Kong Wu Ho-Su Memorial Hospital, Taipei, Taiwan (China); Department of Animal Science, National Ilan University, Ilan, Taiwan (China); Chang, Heng-Jui [Department of Radiation Therapy and Oncology, Shin Kong Wu Ho-Su Memorial Hospital, Taipei, Taiwan (China)] [Department of Radiation Therapy and Oncology, Shin Kong Wu Ho-Su Memorial Hospital, Taipei, Taiwan (China); Chang, Yue-Cune [Department of Mathematics, Tamkang University, Taipei, Taiwan (China)] [Department of Mathematics, Tamkang University, Taipei, Taiwan (China); Huang, Su-Chen; Ko, Hui-Ling; Chang, Chih-Chia [Department of Radiation Therapy and Oncology, Shin Kong Wu Ho-Su Memorial Hospital, Taipei, Taiwan (China)] [Department of Radiation Therapy and Oncology, Shin Kong Wu Ho-Su Memorial Hospital, Taipei, Taiwan (China); Yeh, Yu-Wung; Jiang, Jiunn-Song [Department of Chest Medicine, Shin-Kong Wu Ho-Su Memorial Hospital, Taipei, Taiwan (China)] [Department of Chest Medicine, Shin-Kong Wu Ho-Su Memorial Hospital, Taipei, Taiwan (China); Lee, Cheng-Yen; Chi, Mau-Shin [Department of Radiation Therapy and Oncology, Shin Kong Wu Ho-Su Memorial Hospital, Taipei, Taiwan (China)] [Department of Radiation Therapy and Oncology, Shin Kong Wu Ho-Su Memorial Hospital, Taipei, Taiwan (China); Chi, Kwan-Hwa, E-mail: M006565@ms.skh.org.tw [Department of Radiation Therapy and Oncology, Shin Kong Wu Ho-Su Memorial Hospital, Taipei, Taiwan (China) [Department of Radiation Therapy and Oncology, Shin Kong Wu Ho-Su Memorial Hospital, Taipei, Taiwan (China); Institute of Radiation Science and School of Medicine, National Yang-Ming University, Taipei, Taiwan (China)

    2013-03-01T23:59:59.000Z

    Purpose: To investigate serum markers associated with radiation pneumonitis (RP) grade ?3 in patients with lung cancer who were treated with radiation therapy. Methods and Materials: Pretreatment serum samples from patients with stage Ib-IV lung cancer who developed RP within 1 year after radiation therapy were analyzed to identify a proteome marker able to stratify patients prone to develop severe RP by surface-enhanced laser desorption/ionization time-of-flight mass spectrometry (SELDI-TOF-MS). Dosimetric parameters and 3 biological factors were compared. Results: Serum samples from 16 patients (28%) with severe RP (grade 3-4) and 42 patients (72%) with no or mild RP (grade 0-2) were collected for analysis. All patients received a median of 54 Gy (range, 42-70 Gy) of three-dimensional conformal radiation therapy with a mean lung dose (MLD) of 1502 cGy (range, 700-2794 cGy). An m/z peak of 11,480 Da was identified by SELDI-TOF-MS, and serum amyloid A (SAA) was the primary splitter serum marker. The receiver operating characteristic area under the curve of SAA (0.94; 95% confidence interval [CI], 0.87-1.00) was higher than those of C-reactive protein (0.83; 95% CI, 0.72-0.94), interleukin-6 (0.79; 95% CI, 0.65-0.94), and MLD (0.57; 95% CI, 0.37-0.77). The best sensitivity and specificity of combined SAA and MLD for predicting RP were 88.9% and 96.0%, respectively. Conclusions: Baseline SAA could be used as an auxiliary marker for predicting severe RP. Extreme care should be taken to limit the lung irradiation dose in patients with high SAA.

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

    SciTech Connect (OSTI)

    Hall, E.J.

    1992-05-01T23:59:59.000Z

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

  2. Radiation Safety

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What's PossibleRadiation Protection Radiation Protection Regulations: The Federal Regulation

  3. A Fast local Reconstruction algorithm by selective backprojection for Low-Dose in Dental Computed Tomography

    E-Print Network [OSTI]

    Bin, Yan; Yu, Han; Feng, Zhang; Chao, Wang Xian; Lei, Li

    2013-01-01T23:59:59.000Z

    High radiation dose in computed tomography (CT) scans increases the lifetime risk of cancer, which become a major clinical concern. The backprojection-filtration (BPF) algorithm could reduce radiation dose by reconstructing images from truncated data in a short scan. In dental CT, it could reduce radiation dose for the teeth by using the projection acquired in a short scan, and could avoid irradiation to other part by using truncated projection. However, the limit of integration for backprojection varies per PI-line, resulting in low calculation efficiency and poor parallel performance. Recently, a tent BPF (T-BPF) has been proposed to improve calculation efficiency by rearranging projection. However, the memory-consuming data rebinning process is included. Accordingly, the chose-BPF (C-BPF) algorithm is proposed in this paper. In this algorithm, the derivative of projection is backprojected to the points whose x coordinate is less than that of the source focal spot to obtain the differentiated backprojection...

  4. A work bibliography on native food consumption, demography and lifestyle. Hanford Environmental Dose Reconstruction Project

    SciTech Connect (OSTI)

    Murray, C.E.; Lee, W.J.

    1992-12-01T23:59:59.000Z

    The purpose of this report is to provide a bibliography for the Native American tribe participants in the Hanford Environmental Dose Reconstruction (HEDR) Project to use. The HEDR Project`s primary objective is to estimate the radiation dose that individuals could have received as a result of emissions since 1944 from the US Department of Energy`s Hanford Site near Richland, Washington. Eight Native American tribes are responsible for estimating daily and seasonal consumption of traditional foods, demography, and other lifestyle factors that could have affected the radiation dose received by tribal members. This report provides a bibliography of recorded accounts that tribal researchers may use to verify their estimates. The bibliographic citations include references to information on the specific tribes, Columbia River plateau ethnobotany, infant feeding practices and milk consumption, nutritional studies and radiation, tribal economic and demographic characteristics (1940--1970), research methods, primary sources from the National Archives, regional archives, libraries, and museums.

  5. Does administering iodine in radiological procedures increase patient doses?

    SciTech Connect (OSTI)

    He, Wenjun; Yao, Hai, E-mail: haiyao@clemson.edu [Clemson-MUSC Bioengineering Program, Department of Bioengineering, Clemson University, Charleston, South Carolina 29425 (United States); Huda, Walter; Mah, Eugene [Department of Radiology and Radiological Science, Medical University of South Carolina (MUSC), Charleston, South Carolina 29425 (United States)

    2014-11-01T23:59:59.000Z

    Purpose: The authors investigated the changes in the pattern of energy deposition in tissue equivalent phantoms following the introduction of iodinated contrast media. Methods: The phantom consisted of a small “contrast sphere,” filled with water or iodinated contrast, located at the center of a 28 cm diameter water sphere. Monte Carlo simulations were performed using MCNP5 codes, validated by simulating irradiations with analytical solutions. Monoenergetic x-rays ranging from 35 to 150 keV were used to simulate exposures to spheres containing contrast agent with iodine concentrations ranging from 1 to 100 mg/ml. Relative values of energy imparted to the contrast sphere, as well as to the whole phantom, were calculated. Changes in patterns of energy deposition around the contrast sphere were also investigated. Results: Small contrast spheres can increase local absorbed dose by a factor of 13, but the corresponding increase in total energy absorbed was negligible (<1%). The highest localized dose increases were found to occur at incident photon energies of about 60 keV. For a concentration of about 10 mg/ml, typical of clinical practice, localized absorbed doses were generally increased by about a factor of two. At this concentration of 10 mg/ml, the maximum increase in total energy deposition in the phantom was only 6%. These simulations demonstrated that increases in contrast sphere doses were offset by corresponding dose reductions at distal and posterior locations. Conclusions: Adding iodine can result in values of localized absorbed dose increasing by more than an order of magnitude, but the total energy deposition is generally very modest (i.e., <10%). Their data show that adding iodine primarily changes the pattern of energy deposition in the irradiated region, rather than increasing patient doses per se.

  6. Determination of photon conversion factors relating exposure and dose for several extremity phantom designs

    SciTech Connect (OSTI)

    Roberson, P.L.; Eichner, F.N.; Reece, W.D. (Pacific Northwest Lab., Richland, WA (USA))

    1989-11-01T23:59:59.000Z

    Dosimetric measurements were performed to determine the exposure-to-dose conversion factors (Cx) for simple extremity phantoms suitable for extremity dosimeter performance testing. The phantoms studied represented the forearm or lower leg and the finger. Measurements were performed for solid plastic phantoms and for phantoms containing simulated bone material to determine the effect of backscattered radiations from the simulated bone to the phantom surface. Photon beam energies used for the measurements ranged from 16 keV to 1.25 MeV (average). The Cx factors for the finger phantoms did not vary significantly with phantom composition. The Cx factors in the arm/leg phantoms with the bone simulant material differed significantly from those for the solid plastic phantom over the energy range of 40-100 keV. This effect was attributed to the preferential absorption of the lower energy backscattered photons by the higher atomic number material that was contained in the bone-simulant insert. The position of the bone-simulating material below the surface of the phantom was more important than its size or level of bone equivalency. For calibrations and dosimeter testing, Al was found adequate as a bone-simulating material.

  7. Radiological survey and evaluation of the fallout area from the Trinity test: Chupadera Mesa and White Sands Missile Range, New Mexico

    SciTech Connect (OSTI)

    Hansen, W.R.; Rodgers, J.C.

    1985-06-01T23:59:59.000Z

    Current radiological conditions were evaluated for the site of the first nuclear weapons test, the Trinity test, and the associated fallout zone. The test, located on White Sands Missile Range, was conducted as part of the research with nuclear materials for the World War II Manhattan Engineer District atomic bomb project. Some residual radioactivity attributable to the test was found in the soils of Ground Zero on White Sands Missile Range and the areas that received fallout from the test. The study considered relevant information including historical records, environmental data extending back to the 1940s, and new data acquired by field sampling and measurements. Potential exposures to radiation were evaluated for current land uses. Maximum estimated doses on Chupadera Mesa and other uncontrolled areas are less than 3% of the DOE Radiation Protection Standards (RPSs). Radiation exposures during visits to the US Army-controlled Ground Zero area are less than 1 mrem per annual visit or less than 0.2% of the RPS for a member of the public. Detailed data and interpretations are provided in appendixes. 14 figs., 45 tabs.

  8. Reference Radiation for Cosmic Rays in RBE Research

    E-Print Network [OSTI]

    Feng, Shaoyong

    2011-10-21T23:59:59.000Z

    effectiveness relative to a specific radiation is usually used. For low energy heavy ions and neutrons 250 keV photons are usually used for the reference radiation but their depth dose distribution is very different from that for cosmic rays. In this research...

  9. Radiation Shielding and Radiological Protection

    E-Print Network [OSTI]

    Shultis, J. Kenneth

    .......................................... .. Dose Conversion Factors for Geometric Phantoms ............................ .. Dose Coefficients ....................................................................... Conversion of Fluence to Dose ............................................... . Local Dosimetric Quantities ....................................................... .. Energy Imparted and Absorbed Dose ............................................ .. Kerma

  10. Impulse radar with swept range gate

    DOE Patents [OSTI]

    McEwan, Thomas E. (Livermore, CA)

    1998-09-08T23:59:59.000Z

    A radar range finder and hidden object locator is based on ultra-wide band radar with a high resolution swept range gate. The device generates an equivalent time amplitude scan with a typical range of 4 inches to 20 feet, and an analog range resolution as limited by a jitter of on the order of 0.01 inches. A differential sampling receiver is employed to effectively eliminate ringing and other aberrations induced in the receiver by the near proximity of the transmit antenna (10), so a background subtraction is not needed, simplifying the circuitry while improving performance. Techniques are used to reduce clutter in the receive signal, such as decoupling the receive (24) and transmit cavities (22) by placing a space between them, using conductive or radiative damping elements on the cavities, and using terminating plates on the sides of the openings. The antennas can be arranged in a side-by-side parallel spaced apart configuration or in a coplanar opposed configuration which significantly reduces main bang coupling.

  11. Impulse radar with swept range gate

    DOE Patents [OSTI]

    McEwan, T.E.

    1998-09-08T23:59:59.000Z

    A radar range finder and hidden object locator is based on ultra-wide band radar with a high resolution swept range gate. The device generates an equivalent time amplitude scan with a typical range of 4 inches to 20 feet, and an analog range resolution as limited by a jitter of on the order of 0.01 inches. A differential sampling receiver is employed to effectively eliminate ringing and other aberrations induced in the receiver by the near proximity of the transmit antenna, so a background subtraction is not needed, simplifying the circuitry while improving performance. Techniques are used to reduce clutter in the receive signal, such as decoupling the receive and transmit cavities by placing a space between them, using conductive or radiative damping elements on the cavities, and using terminating plates on the sides of the openings. The antennas can be arranged in a side-by-side parallel spaced apart configuration or in a coplanar opposed configuration which significantly reduces main bang coupling. 25 figs.

  12. Ris National Laboratory DTU Radiation Research Department

    E-Print Network [OSTI]

    the atmosphere to the human thyroid via the food chain and inhalation, and found that the radiation dose of 131 I can not only cause external irradiation of the skin, but also an internal irradiation of the thyroid and whole body. In addition, radioiodine deposited on clothes and hair can also cause skin irradiation

  13. Physics of intense, high energy radiation effects.

    SciTech Connect (OSTI)

    Hjalmarson, Harold Paul; Hartman, E. Frederick; Magyar, Rudolph J.; Crozier, Paul Stewart

    2011-02-01T23:59:59.000Z

    This document summarizes the work done in our three-year LDRD project titled 'Physics of Intense, High Energy Radiation Effects.' This LDRD is focused on electrical effects of ionizing radiation at high dose-rates. One major thrust throughout the project has been the radiation-induced conductivity (RIC) produced by the ionizing radiation. Another important consideration has been the electrical effect of dose-enhanced radiation. This transient effect can produce an electromagnetic pulse (EMP). The unifying theme of the project has been the dielectric function. This quantity contains much of the physics covered in this project. For example, the work on transient electrical effects in radiation-induced conductivity (RIC) has been a key focus for the work on the EMP effects. This physics in contained in the dielectric function, which can also be expressed as a conductivity. The transient defects created during a radiation event are also contained, in principle. The energy loss lead the hot electrons and holes is given by the stopping power of ionizing radiation. This information is given by the inverse dielectric function. Finally, the short time atomistic phenomena caused by ionizing radiation can also be considered to be contained within the dielectric function. During the LDRD, meetings about the work were held every week. These discussions involved theorists, experimentalists and engineers. These discussions branched out into the work done in other projects. For example, the work on EMP effects had influence on another project focused on such phenomena in gases. Furthermore, the physics of radiation detectors and radiation dosimeters was often discussed, and these discussions had impact on related projects. Some LDRD-related documents are now stored on a sharepoint site (https://sharepoint.sandia.gov/sites/LDRD-REMS/default.aspx). In the remainder of this document the work is described in catergories but there is much overlap between the atomistic calculations, the continuum calculations and the experiments.

  14. Management of Pediatric Spinal Cord Astrocytomas: Outcomes With Adjuvant Radiation

    SciTech Connect (OSTI)

    Guss, Zachary D.; Moningi, Shalini [Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins Hospital, Baltimore, Maryland (United States)] [Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins Hospital, Baltimore, Maryland (United States); Jallo, George I. [Department of Neurosurgery, Johns Hopkins Hospital, Baltimore, Maryland (United States)] [Department of Neurosurgery, Johns Hopkins Hospital, Baltimore, Maryland (United States); Cohen, Kenneth J. [Division of Pediatric Oncology, Johns Hopkins Hospital, Baltimore, Maryland (United States)] [Division of Pediatric Oncology, Johns Hopkins Hospital, Baltimore, Maryland (United States); Wharam, Moody D. [Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins Hospital, Baltimore, Maryland (United States)] [Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins Hospital, Baltimore, Maryland (United States); Terezakis, Stephanie A., E-mail: stereza1@jhmi.edu [Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins Hospital, Baltimore, Maryland (United States)

    2013-04-01T23:59:59.000Z

    Purpose: Pediatric intramedullary spinal cord tumors are exceedingly rare; in the United States, 100 to 200 cases are recognized annually, of these, most are astrocytomas. The purpose of this study is to report the outcomes in pediatric patients with spinal cord astrocytomas treated at a tertiary care center. Methods and Materials: An institutional review board-approved retrospective single-institution study was performed for pediatric patients with spinal cord astrocytomas treated at our hospital from 1990 to 2010. The patients were evaluated on the extent of resection, progression-free survival (PFS), and development of radiation-related toxicities. Kaplan-Meier curves and multivariate regression model methods were used for analysis. Results: Twenty-nine patients were included in the study, 24 with grade 1 or 2 (low-grade) tumors and 5 with grade 3 or 4 (high-grade) tumors. The median follow-up time was 55 months (range, 1-215 months) for patients with low-grade tumors and 17 months (range, 10-52 months) for those with high-grade tumors. Thirteen patients in the cohort received chemotherapy. All patients underwent at least 1 surgical resection. Twelve patients received radiation therapy to a median radiation dose of 47.5 Gy (range, 28.6-54.0 Gy). Fifteen patients with low-grade tumors and 1 patient with a high-grade tumor exhibited stable disease at the last follow-up visit. Acute toxicities of radiation therapy were low grade, whereas long-term sequelae were infrequent and manageable when they arose. All patients with low-grade tumors were alive at the last follow-up visit, compared with 1 patient with a high-grade tumor. Conclusion: Primary pediatric spinal cord astrocytomas vary widely in presentation and clinical course. Histopathologic grade remains a major prognostic factor. Patients with low-grade tumors tend to have excellent disease control and long-term survival compared to those with high-grade tumors. This experience suggests that radiation therapy may enhance tumor control with an acceptably low risk of long-term sequelae in this sensitive patient population.

  15. Evaluation of radiation damage using nonlinear ultrasound

    SciTech Connect (OSTI)

    Matlack, K. H. [G.W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332 (United States); Wall, J. J. [G.W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332 (United States); Electric Power Research Institute, Charlotte, North Carolina 28262 (United States); Kim, J.-Y. [School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332 (United States); Qu, J. [Department of Civil and Environmental Engineering, Northwestern University, Evanston, Illinois 60208 (United States); Jacobs, L. J. [G.W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332 (United States); School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332 (United States); Viehrig, H.-W. [Department of Structural Materials, Helmholtz Zentrum Dresden-Rossendorf, Institute of Ion-Beam Physics and Materials Research, P.O. Box 510119, 01314 Dresden (Germany)

    2012-03-01T23:59:59.000Z

    Nonlinear ultrasound was used to monitor radiation damage in two reactor pressure vessel (RPV) steels. The microstructural changes associated with radiation damage include changes in dislocation density and the formation of precipitates, and nonlinear ultrasonic waves are known to be sensitive to such changes. Six samples each of two different RPV steels were previously irradiated in the Rheinsberg power reactor to two fluence levels, up to 10{sup 20} n/cm{sup 2} (E > 1 MeV). Longitudinal waves were used to measure the acoustic nonlinearity in these samples, and the results show a clear increase in the measured acoustic nonlinearity from the unirradiated state to the medium dose, and then a decrease from medium dose to high dose.

  16. Study on neutron radiation field of carbon ions therapy

    E-Print Network [OSTI]

    Xu, Jun-Kui; Li, Wu-Yuan; Yan, Wei-Wei; Chen, Xi-Meng; Mao, Wang; Pang, Cheng-Guo

    2015-01-01T23:59:59.000Z

    Carbon ions offer significant advantages for deep-seated local tumors therapy due to their physical and biological properties. Secondary particles, especially neutrons caused by heavy ion reactions should be carefully considered in treatment process and radiation protection. For radiation protection purposes, the FLUKA Code was used in order to evaluate the radiation field at deep tumor therapy room of HIRFL in this paper. The neutron energy spectra, neutron dose and energy deposition of carbon ion and neutron in tissue-like media was studied for bombardment of solid water target by 430MeV/u C ions. It is found that the calculated neutron dose have a good agreement with the experimental date, and the secondary neutron dose may not exceed one in a thousand of the carbon ions dose at Bragg peak area in tissue-like media.

  17. Ground-water contribution to dose from past Hanford Operations

    SciTech Connect (OSTI)

    Freshley, M.D.; Thorne, P.D.

    1992-08-01T23:59:59.000Z

    The Hanford Environmental Dose Reconstruction (HEDR) 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 migrating 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 next to the Columbia River downstream of Hanford that draw some or all of their water from the river (riparian wells); and (4) through atmospheric deposition resulting in contamination of a small watershed that, in turn, results in contamination of a shallow well or spring by transport in the ground water. These four pathways make up the ground-water pathway,'' which is the subject of this study. Assessment of the ground-water pathway was performed by (1) reviewing the existing extensive literature on ground water and ground-water monitoring at Hanford and (2) performing calculations to estimate radionuclide concentrations where no monitoring data were collected. Radiation doses that would result from exposure to these radionuclides were calculated.

  18. Method for increased sensitivity of radiation detection and measurement

    DOE Patents [OSTI]

    Miller, Steven D. (Richland, WA)

    1994-01-01T23:59:59.000Z

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

  19. Absorbed Gamma-Ray Doses due to Natural Radionuclides in Building Materials

    SciTech Connect (OSTI)

    Aguiar, Vitor A. P.; Medina, Nilberto H. [Instituto de Fisica, Universidade de Sao Paulo, SP (Brazil); Moreira, Ramon H.; Silveira, Marcilei A. G. [Departamento de Fisica, Centro Universitario da FEI, Sao Bernardo do Campo, SP (Brazil)

    2010-05-21T23:59:59.000Z

    This work is devoted to the application of high-resolution gamma-ray spectrometry in the study of the effective dose coming from naturally occurring radionuclides, namely {sup 40}K, {sup 232}Th and {sup 238}U, present in building materials such as sand, cement, and granitic gravel. Four models were applied to estimate the effective dose and the hazard indices. The maximum estimated effective dose coming from the three reference rooms considered is 0.90(45) mSv/yr, and maximum internal hazard index is 0.77(24), both for the compact clay brick reference room. The principal gamma radiation sources are cement, sand and bricks.

  20. Radiation receiver

    DOE Patents [OSTI]

    Hunt, A.J.

    1983-09-13T23:59:59.000Z

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

  1. Radiation receiver

    DOE Patents [OSTI]

    Hunt, Arlon J. (Oakland, CA)

    1983-01-01T23:59:59.000Z

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

  2. An assessment of the resolution limitation due to radiation-damage in X-ray diffraction microscopy

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

    Howells, M.R.; Beetz, T.; Chapman, H.N.; Cui, C.; Holton, J.M.; Jacobsen, C.J.; Kirz, J.; Lima, E.; Marchesini, S.; Miao, H.; et al

    2009-03-01T23:59:59.000Z

    X-ray diffraction microscopy (XDM) is a new form of x-ray imaging that is being practiced at several third-generation synchrotron-radiation x-ray facilities. Nine years have elapsed since the technique was first introduced and it has made rapid progress in demonstrating high-resolution three-dimensional imaging and promises few-nm resolution with much larger samples than can be imaged in the transmission electron microscope. Both life- and materials-science applications of XDM are intended, and it is expected that the principal limitation to resolution will be radiation damage for life science and the coherent power of available x-ray sources for material science. In this paper wemore »address the question of the role of radiation damage. We use a statistical analysis based on the so-called "dose fractionation theorem" of Hegerl and Hoppe to calculate the dose needed to make an image of a single life-science sample by XDM with a given resolution. We find that for simply-shaped objects the needed dose scales with the inverse fourth power of the resolution and present experimental evidence to support this finding. To determine the maximum tolerable dose we have assembled a number of data taken from the literature plus some measurements of our own which cover ranges of resolution that are not well covered otherwise. The conclusion of this study is that, based on the natural contrast between protein and water and "Rose-criterion" image quality, one should be able to image a frozen-hydrated biological sample using XDM at a resolution of about 10 nm.« less

  3. An assessment of the resolution limitation due to radiation-damage in X-ray diffraction microscopy

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

    Howells, M.R.; Beetz, T.; Chapman, H.N.; Cui, C.; Holton, J.M.; Jacobsen, C.J.; Kirz, J.; Lima, E.; Marchesini, S.; Miao, H.; Sayre, D.; Shapiro, D.A.; Spence, J.C.H.; Starodub, D.

    2009-03-01T23:59:59.000Z

    X-ray diffraction microscopy (XDM) is a new form of x-ray imaging that is being practiced at several third-generation synchrotron-radiation x-ray facilities. Nine years have elapsed since the technique was first introduced and it has made rapid progress in demonstrating high-resolution three-dimensional imaging and promises few-nm resolution with much larger samples than can be imaged in the transmission electron microscope. Both life- and materials-science applications of XDM are intended, and it is expected that the principal limitation to resolution will be radiation damage for life science and the coherent power of available x-ray sources for material science. In this paper we address the question of the role of radiation damage. We use a statistical analysis based on the so-called "dose fractionation theorem" of Hegerl and Hoppe to calculate the dose needed to make an image of a single life-science sample by XDM with a given resolution. We find that for simply-shaped objects the needed dose scales with the inverse fourth power of the resolution and present experimental evidence to support this finding. To determine the maximum tolerable dose we have assembled a number of data taken from the literature plus some measurements of our own which cover ranges of resolution that are not well covered otherwise. The conclusion of this study is that, based on the natural contrast between protein and water and "Rose-criterion" image quality, one should be able to image a frozen-hydrated biological sample using XDM at a resolution of about 10 nm.

  4. Dose response of selected ion chambers in applied homogeneous transverse and longitudinal magnetic fields

    SciTech Connect (OSTI)

    Reynolds, M. [Department of Oncology, Medical Physics Division, University of Alberta, 11560 University Avenue, Edmonton, Alberta T6G 1Z2 (Canada); Fallone, B. G. [Department of Medical Physics, Cross Cancer Institute, 11560 University Avenue, Edmonton, Alberta T6G 1Z2 (Canada); Departments of Oncology and Physics, University of Alberta, 11560 University Avenue, Edmonton, Alberta T6G 1Z2 (Canada); Rathee, S. [Department of Medical Physics, Cross Cancer Institute, 11560 University Avenue, Edmonton, Alberta T6G 1Z2 (Canada); Department of Oncology, Medical Physics Division, University of Alberta, 11560 University Avenue, Edmonton, Alberta T6G 1Z2 (Canada)

    2013-04-15T23:59:59.000Z

    Purpose: The magnetic fields of an integrated MR-Linac system will alter the paths of electrons that produce ions in the ionization chambers. The dose response of selected ion chambers is evaluated in the presence of varying transverse and longitudinal magnetic fields. The investigation is useful in calibration of therapeutic x-ray beams associated with MR-Linac systems. Methods: The Monte Carlo code PENELOPE was used to model the irradiation of NE2571, and PR06C ionization chambers in the presence of a transverse and longitudinal (with respect to the photon beam) magnetic fields of varying magnitude. The long axis of each chamber was simulated both parallel and perpendicular to the incident photon beam for each magnetic field case. The dose deposited in each chamber for each case was compared to the case with zero magnetic field by means of a ratio. The PR06C chamber's response was measured in the presence of a transverse magnetic field with field strengths ranging from 0.0 to 0.2 T to compare to simulated results. Results: The simulations and measured data show that in the presence of a transverse magnetic field there is a considerable dose response (maximum of 11% near 1.0 T in the ion chambers investigated, which depends on the magnitude of magnetic field, and relative orientation of the magnetic field, radiation beam, and ion chamber. Measurements made with the PR06C chamber verify these results in the region of measurement. In contrast, a longitudinal magnetic field produces only a slight increase in dose response (2% at 1.5 T) that rises slowly with increasing magnetic field and is seemingly independent of chamber orientation. Response trends were similar for the two ion chambers and relative orientations considered, but slight variations are present from chamber to chamber. Conclusions: Care must be taken when making ion chamber measurements in a transverse magnetic field. Ion chamber responses vary not only with transverse field strength, but with chamber orientation and type, and can be considerable. Longitudinal magnetic fields influence ion chamber responses relatively little (2% at 1.5 T), and only at field strengths in excess of 1.0 T.

  5. Gravitational Radiation

    E-Print Network [OSTI]

    Bernard F Schutz

    2000-03-16T23:59:59.000Z

    Gravity is one of the fundamental forces of Nature, and it is the dominant force in most astronomical systems. In common with all other phenomena, gravity must obey the principles of special relativity. In particular, gravitational forces must not be transmitted or communicated faster than light. This means that when the gravitational field of an object changes, the changes ripple outwards through space and take a finite time to reach other objects. These ripples are called gravitational radiation or gravitational waves. This article gives a brief introduction to the physics of gravitational radiation, including technical material suitable for non-specialist scientists.

  6. Physical and biological factors determining the effective proton range

    SciTech Connect (OSTI)

    Grün, Rebecca [Department of Biophysics, GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt 64291 (Germany) [Department of Biophysics, GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt 64291 (Germany); Institute of Medical Physics and Radiation Protection, University of Applied Sciences Gießen, Gießen 35390 (Germany); Medical Faculty of Philipps-University Marburg, Marburg 35032 (Germany); Friedrich, Thomas; Krämer, Michael; Scholz, Michael [Department of Biophysics, GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt 64291 (Germany)] [Department of Biophysics, GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt 64291 (Germany); Zink, Klemens [Institute of Medical Physics and Radiation Protection, University of Applied Sciences Gießen, Gießen 35390, Germany and Department of Radiotherapy and Radiation Oncology, University Medical Center Giessen and Marburg, Marburg 35043 (Germany)] [Institute of Medical Physics and Radiation Protection, University of Applied Sciences Gießen, Gießen 35390, Germany and Department of Radiotherapy and Radiation Oncology, University Medical Center Giessen and Marburg, Marburg 35043 (Germany); Durante, Marco [Department of Biophysics, GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt 64291, Germany and Department of Condensed Matter Physics, Darmstadt University of Technology, Darmstadt 64289 (Germany)] [Department of Biophysics, GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt 64291, Germany and Department of Condensed Matter Physics, Darmstadt University of Technology, Darmstadt 64289 (Germany); Engenhart-Cabillic, Rita [Medical Faculty of Philipps-University Marburg, Marburg 35032, Germany and Department of Radiotherapy and Radiation Oncology, University Medical Center Giessen and Marburg, Marburg 35043 (Germany)] [Medical Faculty of Philipps-University Marburg, Marburg 35032, Germany and Department of Radiotherapy and Radiation Oncology, University Medical Center Giessen and Marburg, Marburg 35043 (Germany)

    2013-11-15T23:59:59.000Z

    Purpose: Proton radiotherapy is rapidly becoming a standard treatment option for cancer. However, even though experimental data show an increase of the relative biological effectiveness (RBE) with depth, particularly at the distal end of the treatment field, a generic RBE of 1.1 is currently used in proton radiotherapy. This discrepancy might affect the effective pen