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Preliminary assessment of tree mortality near F- and H-area seepage basins

Description: A preliminary assessment was conducted to evaluate factors that may have been responsible for the vegetation damage that has occurred in groundwater seeps downslope from the F- and H-area seepage basins. The factors that were considered included altered hydrology, toxicity from hazardous chemical constituents associated with seepage basin operation, and toxicity from non-hazardous constituents associated with basin operation. It was concluded that the observed damage was not likely to have resu… more
Date: January 28, 1988
Creator: Loehle, C & Gladden, J
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Clonal theory of radiation carcinogenesis

Description: In some cases, usually involving high-LET radiations, the dose response at low doses follows a power function of dose with exponent less than one over a wide dose range. This type of response is of great interest since (a) it implies greater effect per unit dose at progressively smaller doses, and (b) it is not predicted by most models and theories of radiobiology. A theoretical framework is presented for responses having the above characteristics over a dose range extending over a factor of 10… more
Date: January 1, 1982
Creator: Baum, J.W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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TRITOX: a multiple parameter evaluation of tritium toxicity

Description: The increased use of nuclear reactors for power generation will lead to the introduction of tritium into the environment. The need for assessing possible immediate and long-term effects of exposure to this tritium led to the development of a broad program directed towards evaluating the possible somatic and genetic effects of continuous exposure to tritiated water (HTO). Among the parameters measured are the genetic, cytogenetic, reproductive efficiency, growth, nonspecific lifetime shortening,… more
Date: January 1, 1982
Creator: Carsten, A.L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Analytical review of structure and regulation of hemopoiesis

Description: The development of knowledge on the structure of hemopoiesis and its regulation can be divided into four broad areas: descriptive morphology, kinetics of cell proliferation, regulation of rates of cell proliferation through interaction of molecular regulators and their cell surface receptors, and clinical applications. 60 refs., 6 figs.
Date: January 1, 1987
Creator: Cronkite, E.P.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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DNA repair in spermatocytes and spermatids of the mouse

Description: When male mice are exposed to chemical agents that reach the germ cells several outcomes are possible in terms of the germ cell unscheduled DNA synthesis (UDS) response and removal of DNA adducts. It is possible that: the chemical binds to the DNA and induces a UDS response with concomittant removal of DNA adducts; the chemical binds to the DNA but no UDS response is induced; or the chemical does not bind to DNA and no UDS is induced. Many mutagens have been shown to induce a UDS response in po… more
Date: January 1, 1982
Creator: Sega, G.A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Dose-rate models for human survival after exposure to ionizing radiation

Description: This paper reviews new estimates of the L/sub 50/ in man by Mole and by Rotblat, the biological processes contributing to hematologic death, the collection of animal experiments dealing with hematologic death, and the use of regression analysis to make new estimates of human mortality based on all relevant animal studies. Regression analysis of animal mortality data has shown that mortality is dependent strongly on dose rate, species, body weight, and time interval over which the exposure is de… more
Date: January 1, 1986
Creator: Jones, T.D.; Morris, M.D. & Young, R.W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Qualitative analysis of mouse specific-locus mutations: information on genetic organization, gene expression, and the chromosomal nature of induced lesions

Description: Analysis of mouse specific-locus (SL) mutations at three loci has identified over 33 distinct complementation groups - most of which are probably overlapping deficiencies - and 13 to 14 new functional units. The complementation maps that have been generated for the d-se and c regions include numerous vital functions; however, some of the genes in these regions are non-vital. At such loci, hypomorphic mutants must represent intragenic alterations, and some viable nulls could conceivably be intra… more
Date: January 1, 1982
Creator: Russell, L.B.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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UV action spectra for mammalian systems: their implications for the predicted effects of ozone depletion on skin cancer incidence

Description: The predicted environmental effect of UV-B depend on the action spectrum for the response studied. Since such spectra change rapidly - usually decreasing with increasing wavelength - and since the biological effects depend on the product of the action spectrum and the sun's spectrum at the surface of the earth which decreases with decreasing wavelength, a slight change in action spectrum will markedly influence the predicted effects of ozone depletion on biological systems. Thus, the key, but b… more
Date: January 1, 1982
Creator: Setlow, R.B.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Mechanisms for radiation damage in DNA. Progress report, January 1, 1982-December 31, 1982

Description: In this project several mechanisms are proposed for radiation damage to DNA constituents and DNA, and a series of experiments utilizing electron spin resonance spectrometry to test the proposed mechanisms have been detailed. In the past studies have concentrated chiefly on the direct effect of radiation on DNA. We are currently investigating irradiated systems of DNA constituents which may shed light on indirect effects. In addition, studies of radiation effects on lipids have been undertaken w… more
Date: May 1, 1982
Creator: Sevilla, M. D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Assessment of the response of spent fuel transports to malevolent acts

Description: This paper describes the results of a program conducted at Sandia National Laboratories (SNL) for the US Department of Energy to provide an experimental data base for more accurately assessing the radiological consequences from a hypothetical sabotage attack on a spent fuel shipping cask. The primary objectives of the program were limited to: (1) evaluating the effectiveness of selected high explosive devices (HED) in breaching full-size spent fuel casks, (2) quantifying and characterizing rele… more
Date: December 20, 1983
Creator: Sandoval, R.P.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Some properties of the log-Laplace distribution

Description: A random variable ..gamma.. is said to have the Laplace distribution or the double exponential distribution whenever its probability density function is given by lambda exp(-lambda absolute value (y)), where -infinity < y < infinity and lambda > 0. The random variable X = exp(..gamma..) is said to have the log-Laplace distribution. With the problem of extrapolation to low doses in dose response curves as a motivation, an axiomatic characterization of the log-Laplace distribution is obtained. 1 … more
Date: August 1, 1980
Creator: Uppuluri, V.R.R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Does oxygen enhance the radiation-induced inactivation of penicillinase. Progress report, December 1, 1979-November 30, 1980

Description: The radiation-induced inactivation of penicillinase in dilute aqueous solutions buffered with phosphate was studied, by examining enzyme radiosensitivity in the presence of various gases (He, O/sub 2/, H/sub 2/, N/sub 2/O, N/sub 2/O + O/sub 2/). The introduction of either N/sub 2/O or O/sub 2/ was found to reduce the radiodamage. On the other hand H/sub 2/ or N/sub 2/O + O/sub 2/ gas-mixture enhanced the radiosensitivity. In the presence of formate and oxygen, no enzyme inactivation was detecte… more
Date: January 1, 1980
Creator: Samuni, A.; Kalkstein, A. & Czapski, G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Utilization of critical periods during development to study the effects of low levels of environmental agents

Description: Careful definition of critical periods in the development of selected characters can result in experimental systems that may be highly useful in studying risk at low levels of exposure. Three examples are presented. Epidemiological investigations can lose much of their value unless critical periods are known for the end points being studied.
Date: January 1, 1980
Creator: Russell, L.B.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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(In vivo mutagenicity and clastogenicity of ionizing radiation in nuclear medicine)

Description: The overall goals of our research remains to investigate the mutagenic and clastogenic effects of exposure to low levels of ionizing radiation in human lymphocytes. We are studying hospital patients referred to a nuclear medicine department for diagnostic cardiac imaging and nuclear medicine technologists who administer radionuclides.
Date: January 1, 1989
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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UV dose-effect relationships and current protection exposure standards

Description: In this paper we have attempted to quantify the health effects in man of uv-radiation exposure of wavelengths from 240 nm to 320 nm. Exposure to uv in this region could result in the formation of skin cancer or premature aging in man. The induction of cancer by uv radiation results from changes in genetic material. We have used the DNA action spectrum coupled with the uv skin cancer data available in the literature to derive the dose-effect relationships. The results are compared against the cu… more
Date: April 1, 1982
Creator: Singh, M.S. & Campbell, G.W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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DNA repair in human cells exposed to combinations of carcinogenic agents

Description: Normal human and XP/sup 2/ fibroblasts were treated with uv plus uv-mimetic chemicals. The uv dose used was sufficient to saturate the uv excision repair system. Excision repair after combined treatments was estimated by unscheduled DNA synthesis, BrdUrd photolysis, and the loss of sites sensitive to a uv specific endonuclease. Since the repair of damage from uv and its mimetics is coordinately controlled we expected that there would be similar rate-limiting steps in the repair of uv and chemic… more
Date: January 1, 1980
Creator: Setlow, R.B. & Ahmed, F.E.
Item Type: Refine your search to only Article
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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Ultrastructural effects of radiation on cells and tissues: concluding remarks

Description: Concluding remarks which condense the subject matter covered in the preceding series of reports which indicate the complex nature of the biological response to ionizing radiation and the inherent difficulties associated with developing unifying concepts and definitions. The multiplicity of the major response variables, i.e., specimen type, radiation parameters, analytical approach and endpoints measured, is undoubtedly a major problem. In these studies, the specimens analyzed ranged from eucary… more
Date: January 1, 1982
Creator: Seed, T.M. & Carr, K.E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Mammary carcinogenesis in rats: basic facts and recent results in Brookhaven

Description: Some research results from experiments investigating neutron-induced mammary carcinogenesis in rats are presented. The additive effects of neutrons and 3-methylcholanthrene on mammary adenocarcinoma were determined. Synergism between diethylstilbestrol and neutrons was likewise studied. Differences in mammary neoplastic response between strains of laboratory rats was also investigated. (ACR)
Date: January 1, 1982
Creator: Shellabarger, C.J.; Stone, J.P. & Holtzman, s.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Low-exposure tritium radiotoxicity in mammals

Description: Studies of tritium radiotoxicity involving chronic /sup 3/H0H exposures in mammals demonstrate in both mice and monkeys that biological effects can be measured following remarkably low levels of exposure - levels in the range of serious practical interest to radiation protection. These studies demonstrate also that deleterious effects of /sup 3/H beta radiation do not differ significantly from those of gamma radiation at high exposures. In contrast, however, at low exposures tritium is signific… more
Date: February 11, 1982
Creator: Dobson, R.L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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BEIR-III controverly

Description: How certain of the areas addressed by the Committee on the Biological Effects of Ionizing Radiation (BEIR) have attempted to deal with the scientific basis for establishing appropriate radiation protection guides is discussed, and what effect this may have on decision-making for the regulation of societal activities concerned with the health effects in human populations exposed to low-level radiation. (ACR)
Date: June 1, 1980
Creator: Fabrikant, Jacob I.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Quantitative and molecular analyses of mutation in a pSV2gpt transformed CHO cell line

Description: Following NDA-mediated gene transfer we have isolated a cell line useful for studying gene mutation at the molecular level. This line, AS52, derived from a hypoxanthine-guanine phosphoribosyl transferase (HGPRT) deficient Chinese hamster ovary (CHO) cell line, carries a single copy of the E. coli xanthine-guanine phosphoribosyl transferase (XGPRT) gene (gpt) and exhibits a spontaneous mutant frequency of 20 TG/sup r/ mutants/10/sup 6/ clonable cells. As with HGPRT/sup -/ mutants, XGPRT/sup -/ m… more
Date: January 1, 1983
Creator: Stankowski, L.F. Jr.; Tindall, K.R. & Hsie, A.W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Analysis of potential radiation-induced genetic and somatic effects to man from milling of uranium

Description: Potential mortality from natural causes and from radiation exposure conditions typical of those in the vicinity of uranium mills in the western USA was calculated. The exposure conditions were those assumed to exist in the vicinity of a hypothetical model mill. Dose rates to organs at risk were calculated as a function of time using the Uranium Dispersion and Dosimetry Code (Momeni et al. 1979). The changes in population size, birth rates, and radiation-induced and natural mortalities were calc… more
Date: January 1, 1984
Creator: Momeni, M. H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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