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Investigations of the biological effects of radiation: a multi-discipline approach. Progress report, September 1, 1976--August 31, 1977

Description: The quasi-free electron attachment rate, k/sub e/, and mobility, ..mu../sub e/, were studied in non-polar solutions using pulsed conductivity techniques. Measurements of k/sub e/ of >50 nitro compounds in liquids have ..mu../sub e/ ranging from <0.1 to 100 cm/sup 2//volt sec at temperatures from -100 to +40/sup 0/C indicated electron-dipole interactions are important in liquids having ..mu../sub e/ < 1 cm/sup 2//volt sec. The Smoluchowski equation was modified to include electron-dipole interac… more
Date: September 1, 1977
Creator: Friedell, H.L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Genetic effects of low x-ray doses. Progress report, October 1, 1976--September 30, 1977. [In Drosophila]

Description: A linear-quadratic model of dose-kinetics is proposed for x-ray induced recessive lethal mutations in oogonia of Drosophila. From this it should follow that at higher total doses fractionation treatments should give a lower yield of mutations than an equivalent acute exposure. A dose of 6000 R, given acutely and in 3 different fractionation regimes gave results in the expected direction for 2 x 3000 R, and a significant decrease for 3 x 2000 R and for 4 x 1500 R fractionations.
Date: September 1, 1977
Creator: Abrahamson, S. & Meyer, H.U.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Workshop on radiobiological effectiveness of neutrons

Description: The radiobiological effectiveness (RBE) of neutrons has become the subject of some heated discussions in both scientific and radiation-protection oriented communities. This has become especially so since the realization that neutron exposures of A-bomb survivors in Hiroshima were considerably lower than previously assumed, thus ''devaluating'' the importance of what we thought was a solid human data base. At the same time, more recent data from radiobiological research appeared to indicate that… more
Date: September 1, 1985
Creator: Stapleton, G. E.; Thomas, R. G. & Thiessen, J. W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Linear-quadratic dose kinetics or dose-dependent repair/misrepair

Description: Models for the response of cells exposed to low LET radiation can be grouped into three general types on the basis of assumptions about the nature of the interaction which results in the shoulder of the survival curve. The three forms of interaction are (1) sublethal damage becoming lethal, (2) potentially lethal damage becoming irreparable, and (3) potentially lethal damage saturating'' a repair system. The effects that these three forms of interaction would have on the results of specific typ… more
Date: September 1, 1991
Creator: Braby, L.A. & Nelson, J.M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Technical assessment of the prevention of micro-fouling on OTEC heat-transfer surfaces through the use of ultraviolet radiation

Description: To reduce or eliminate biofouling by microorganisms it has been suggested that the seawater entering the heat exchanger be sterilized (or at least sanitized) by uv radiation at 253.7 nm. The feasibility of applying this technology to OTEC is examined. Trivial calculations based on the Lambert-Beer equation and reasonable assumptions about seawater quality and the intensity of irradiation obtainable from a uv lamp suggest seawater may be transparent enough to a collimated beam of uv light to del… more
Date: September 1, 1981
Creator: Garrigan, G. A.; Schmitt, R. P. & Ciccone, V. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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NMR imaging and spectroscopy of the mammalian central nervous system after heavy ion radiation

Description: NMR imaging, NMR spectroscopic, and histopathologic techniques were used to study the proton relaxation time and related biochemical changes in the central nervous system after helium beam in vivo irradiation of the rodent brain. The spectroscopic observations reported in this dissertation were made possible by development of methods for measuring the NMR parameters of the rodent brain in vivo and in vitro. The methods include (1) depth selective spectroscopy using an optimization of rf pulse e… more
Date: September 1, 1984
Creator: Richards, T.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The potential for new methods to assess human reproductive genotoxicity

Description: The immediate prospects are not good for practical methods for measuring the human heritable mutation rate. The methods discussed here range from speculative to impractical, and at best are sensitive enough only for large numbers of subjects. Given the rapid development of DNA methods and the current status of two-dimensional gel electrophoresis, there is some hope that the intermediate prospects may be better. In contrast, the prospects for useful cellular-based male germinal methods seem more… more
Date: September 1, 1987
Creator: Mendelsohn, M.L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Mechanistic models

Description: Several models and theories are reviewed that incorporate the idea of radiation-induced lesions (repairable and/or irreparable) that can be related to molecular lesions in the DNA molecule. Usually the DNA double-strand or chromatin break is suggested as the critical lesion. In the models, the shoulder on the low-LET survival curve is hypothesized as being due to one (or more) of the following three mechanisms: (1) interaction'' of lesions produced by statistically independent particle tracks; … more
Date: September 1, 1990
Creator: Curtis, S.B.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Low-level radiation: biological interactions, risks, and benefits. A bibliography

Description: The bibliography contains 3294 references that were selected from the Department of Energy's data base (EDB). The subjects covered are lower-level radiation effects on man, environmental radiation, and other biological interactions of radiation that appear to be applicable to the low-level radiation problem.
Date: September 1, 1978
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Phenomenological models

Description: The biological effects of ionizing radiation exposure are the result of a complex sequence of physical, chemical, biochemical, and physiological interactions. One way to begin a search for an understanding of health effects of radiation is through the development of phenomenological models of the response. Many models have been presented and tested in the slowly evolving process of characterizing cellular response. A range of models covering different endpoints and phenomena has developed in pa… more
Date: September 1, 1990
Creator: Braby, L.A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Brookhaven Lecture Series No. 227: The Chernobyl Accident

Description: This lecture discusses the events leading to, during, and following the Chernobyl Reactor number 4 accident. A description of the light water cooled, graphite moderated reactor, the reactor site conditions leading to meltdown is presented. The emission of radioactive effluents and the biological radiation effects is also discussed. (FI)
Date: September 24, 1986
Creator: Kouts, H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Laser-based flow cytometric analysis of genotoxicity of humans exposed to ionizing radiation during the Chernobyl accident

Description: An analytical technique has been developed that allows laser-based flow cytometric measurement of the frequency of red blood cells that have lost allele-specific expression of a cell surface antigen due to genetic toxicity in bone marrow precursor cells. Previous studies demonstrated a correlation of such effects with the exposure of each individual to mutagenic phenomena, such as ionizing radiation, and the effects can persist for the lifetime of each individual. During the emergency response … more
Date: September 12, 1990
Creator: Jensen, R.H.; Bigbee, W.L.; Langlois, R.G.; Grant, S.G. (Lawrence Livermore National Lab., CA (USA)); Pleshanov, P.G. (Ministerstvo Zdravookhraneniya SSSR, Moscow (USSR)); Chirkov, A.A. (Institut Biofiziki, Moscow (USSR)) et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Light ion irradiation for unfavorable soft tissue sarcoma

Description: Between 1978 and 1989, 32 patients with unfavorable soft tissue sarcoma underwent light ion (helium, neon) irradiation with curative intent at Lawrence Berkeley Laboratory. The tumors were located in the trunk in 22 patients and head and neck in 10. Macroscopic tumor was present in 22 at the time of irradiation. Two patients had tumors apparently induced by previous therapeutic irradiation. Follow-up times for surviving patients ranged from 4 to 121 months (median 27 months). The overall 3-year… more
Date: September 1, 1990
Creator: Linstadt, D.; Castro, J.R.; Phillips, T.L.; Petti, P.L.; Collier, J.M.; Daftari, I. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Uranium miner lung cancer study. Progress report for period, July 1, 1977--July 1 1978

Description: This study was initiated in 1957 by the U.S. Public Health, and many facets of this project are reaching final objectives. Many new studies have developed in the course of this study and will continue. The projects supported by The Department of Energy during the past year are of utmost importance and consist of: (a) collection of material from uranium miners known to have cancer of the lung into a tumor registry; (b) completion and publication of the Manual on Pulmonary Cytology; (c) regressio… more
Date: September 15, 1978
Creator: Saccomanno, G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Fatality Risk Estimation for Replacement Tritium Facility

Description: Prompt and latent cancer fatality risks are estimated in this report for the operation of the Replacement Tritium Facility (RTF) at the Savannah River Site (SRS). The purpose of this report is to demonstrate that: (1) the calculated fatality risk for the RTF operation is well within the quantitative Nuclear Safety Goals established by the Department of Energy (DOE) and (2) a simple point estimate method can produce results comparable to those of more detailed calculation utilizing computer code… more
Date: September 1, 1994
Creator: Kim, K. S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Uranium miner lung cancer study. Progress report, July 1, 1975--July 1, 1976

Description: This study on the rate of lung cancer development in uranium miners was initiated in 1957 by the U. S. Public Health and many facets of this project are reaching final objectives. Many new studies have developed in the course of this study and will continue. The projects supported by The Energy Research and Development Administration are of utmost importance and consist of: collection of material from uranium miners known to have cancer of the lung into a tumor registry; manual on pulmonary cyt… more
Date: September 15, 1976
Creator: Saccomanno, G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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CHORD simulation for insult assessment to the red bone marrow. [Photons, neutrons]

Description: Critical Human Organ Radiation Dosimetry (CHORD) probability density functions for A-P, P-A, bilateral, rotational, and isotropic incidence, plus simple depth-dose data, permit the rapid estimation of the radiation insult to the active red bone marrow system of the ICRP Reference Man. The CHORD concept follows the variations in the microscopic processes of absorption, attenuation, and scattering on a macroscopic level so that it is not necessary to attempt detailed calculations for each and eve… more
Date: September 1, 1976
Creator: Jones, T. D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Evaluating the effects of low-level chronic exposures. [Methods used at Hanford]

Description: Problems involved in assessing health effects of chronic low-level exposures to environmental contaminants are reviewed. This problem is illustrated by a study of health effects of occupational exposure to ionizing radiation at Hanford. Hanford was established in the early forties as an installation for plutonium production. Since this time, over 33,000 workers have been employed, many in jobs involving some exposure to radiation. Yearly records of this exposure, as well as occupational data, a… more
Date: September 1, 1976
Creator: Gilbert, E S
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Theory of RBE. Third triennial report, 1 January 1967--31 December 1975. [Model based on tracks of heavy ions in nuclear emulsions]

Description: From a single set of themes, the theory of RBE has developed a picture of the response of many biological, physical, and chemical systems to radiations of different quality, that depends on a model of the structure of the tracks of nuclear projectiles in condensed matter. Its characterizations arise from the tracks of heavy ions in nuclear emulsions, as extended to accommodate biological cells. Most recently emulsions have been identified whose radiosensitivity changes with radiation quality pa… more
Date: September 1, 1975
Creator: Katz, R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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E Division activities report, FY 1976

Description: Some of the activities in E (Experimental Physics) Division are described. E Division carries out basic and applied research in atomic and nuclear physics as well as in material and biomedical sciences, centered around the Laboratory&#x27;s four major accelerators. Experiments are grouped under the headings of neutron, photon, and charged-particle interactions. Investigations in this past year involved fission cross sections, nuclear reactions with neutrons, charged particles and gamma rays, in… more
Date: September 24, 1976
Creator: Barschall, H. H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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