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in subjects: "Biological Radiation Effects"

open access

Tumor production in Syrian hamsters following inhalation of PuO/sub 2/--ZrO/sub 2/ aerosol

Syrian golden hamsters of both sexes were exposed to aerosols of ZrO/sub 2/ containing PuO/sub 2/. The starting material in the aerosol generator also had a small amount of /sup 57/Co added as a tracer. The mixture of all three constituents was nebulized and the droplets passed through a heating column at 1000/sup 0/C. Aerosol sampling was accomplished with a cascade impactor and electrostatic precipitator. The median aerodynamic diameters in all inhalation runs were approximately 2 ..mu..m wit… more

Date: January 1, 1978

Creator: Thomas, R. G. & Smith, D. M.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Health effects models for nuclear power plant accident consequence analysis: Low LET radiation

This report describes dose-response models intended to be used in estimating the radiological health effects of nuclear power plant accidents. Models of early and continuing effects, cancers and thyroid nodules, and genetic effects are provided. Weibull dose-response functions are recommended for evaluating the risks of early and continuing health effects. Three potentially lethal early effects -- the hematopoietic, pulmonary, and gastrointestinal syndromes -- are considered. In addition, model… more

Date: January 1, 1990

Creator: Evans, J. S.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Basic aspects of radiation action on microorganisms. Final report for the period ending October 31, 1977. [Radioresistance of micrococcus luteus]

Progress is reported on studies on the basic aspects of radiation effects on microorganisms. Results are included from studies on the effects of uv pretreatment on the survival of ..gamma..-irradiated micrococcus luteus and uv-induced radioresistance to bacteriophage.

Date: December 1, 1977

Creator: Pollard, E.C.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

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

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: Report

Partner: UNT Libraries Government Documents Department

open access

Clonal theory of radiation carcinogenesis

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: Article

Partner: UNT Libraries Government Documents Department

open access

Radiation induced micrencephaly in guinea pigs

A brain weight deficit of about 70 mg was induced at doses of approximately 75-mGy and a deficit of 60 mg was induced at 100 mGy. This confirms the effects projected and observed by Wanner and Edwards. Although the data do not demonstrate a clear dose-response relationship between the 75-mGy and 100-mGy groups, the data are statistically consistent with a dose-response effect because of the overlapping confidence intervals. The lack of a statistically significant observation is most likely rela… more

Date: January 1, 1991

Creator: Wagner, L.K.; Johnston, D.A. & Felleman, D.J.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Comparative mutagenesis of human cells in vivo and in vitro

This report discusses measuring methods of point mutations; high density cell cultures for low dose studies; measurement and sequence determination of mutations in DNA; the mutational spectra of styrene oxide and ethlyene oxide in TK-6 cells; mutational spectrum of Cr in human lymphoblast cells; mutational spectra of radon in TK-6 cells; and the mutational spectra of smokeless tobacco. (CBS)

Date: May 1, 1992

Creator: Thilly, W.G.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

TRITOX: a multiple parameter evaluation of tritium toxicity

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: Article

Partner: UNT Libraries Government Documents Department

open access

Health physics aspects of nuclear radiations from deuterium beam injectors

Estimations are made for X-ray generation from the accelerator column of various neutral beam injectors. For the case of deuterium beam operation where 2.5-MeV D-D neutrons pose a serious health physics concern, neutron and tritium production rates from beam targets are calculated for different beam energies. Biological doses from these radiations and shielding requirements are discussed.

Date: February 1, 1978

Creator: Kim, J.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Analytical review of structure and regulation of hemopoiesis

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: Article

Partner: UNT Libraries Government Documents Department

open access

DNA repair in spermatocytes and spermatids of the mouse

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: Article

Partner: UNT Libraries Government Documents Department

open access

Dose-rate models for human survival after exposure to ionizing radiation

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: Article

Partner: UNT Libraries Government Documents Department

open access

Qualitative analysis of mouse specific-locus mutations: information on genetic organization, gene expression, and the chromosomal nature of induced lesions

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: Article

Partner: UNT Libraries Government Documents Department

open access

Presence of UV-endonuclease sensitive sites in daughter DNA of UV-irradiated mammalian cells. [3H-thymidine tracer]

Asynchronous Chinese hamster cells were irradiated with 10 Jm/sup -2/ uv radiation and 0.25 to 4 hours later pulse-labeled with (/sup 3/H)thymidine. Cells synchronized by shaking off mitotic and G/sub 1/ cells were irradiated in either the G/sub 1/-phase or S-phase of the cell cycle and pulse-labeled with (/sup 3/H)thymidine in the S-phase. After a 12 to 14 hour chase in unlabeled medium, the DNA was extracted, incubated with Micrococcus luteus uv-endonuclease and sedimented in alkaline sucrose… more

Date: February 1, 1978

Creator: D'Ambrosio, S. & Setlow, R.B.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

UV action spectra for mammalian systems: their implications for the predicted effects of ozone depletion on skin cancer incidence

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: Article

Partner: UNT Libraries Government Documents Department

open access

Mechanisms for radiation damage in DNA. Progress report, January 1, 1982-December 31, 1982

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: Report

Partner: UNT Libraries Government Documents Department

open access

Removal of uv-induced pyrimidine dimers from the replicated and unreplicated DNA of human fibroblasts

Excision repair in uv irradiated human fibroblasts has been examined in portions of DNA replicating after irradiation versus those remaining unreplicated. Two approaches, one using a uv-endonuclease to estimate pyrimidine dimers remaining in DNA, the other using density labeling to measure excision resynthesis, indicate that the extent of repair is the same for both replicated and unreplicated DNA.

Date: January 1, 1978

Creator: Waters, R.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Response of Shortgrass Plains Vegetation to Chronic and Seasonally Administered Gamma Radiation

In order to determine the effect of radiation on the structure of native shortgrass plains vegetation, an 8750 Ci 137Cs source was installed on the Central Plains Experimental Range near Nunn, Colorado; The experimental area was divided into 6 treatment sectors, a control, 2 sectors for chronic exposure (irradiation initiated April 1969 and continuing as of August 1971), and one each for spring, summer and late fall seasonal semi-acute (30 day), exposures which were administered during April, J… more

Date: August 1, 1971

Creator: Fraley, L. Jr.

Item Type: Thesis or Dissertation

Partner: UNT Libraries Government Documents Department

open access

Distinction between the roles of O/sub 2/ and of O/sup -//sub 2/ in biological radiodamage

The paper attempts to elucidate the roles of oxygen and superoxide radical in biological damage due to ionizing radiation. Specifically, the effect of gamma radiation on the survival of T4 bacteriophage and of E. coli B has been investigated. (ACR)

Date: January 1, 1978

Creator: Samuni, A.; Chevion, M.; Halpern, Y. S.; Ilan, Y. A. & Czapski, G.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Excision repair in mammalian cells. [uv radiation, N-acetoxy-2-acetylaminofluorene]

Excision repair after combined treatments of uv and N-acetoxy-2-acetylaminofluorene (AAAF) was studied by three different techniques in cells proficient in uv excision repair and in cells deficient in uv repair. Two patterns of repair were observed: in repair proficient cells total repair was additive, and in repair deficient cells total repair was much less than additive--usually less than observed for separate treatments--and AAAF inhibited dimer excision. We conclude that in the 1st class of… more

Date: January 1, 1978

Creator: Ahmed, F.E. & Setlow, R.B.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Assessment of the response of spent fuel transports to malevolent acts

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: Article

Partner: UNT Libraries Government Documents Department

open access

Studies of human mutation rates

The three objectives of the program are: To isolate by the technique of two-dimensional polyacrylamide gel electrophoresis (2-D PAGE), proteins of special interest because of the relative mutability of the corresponding gene, establish the identity of the protein, and, for selected proteins, move to a characterization of the corresponding gene; To develop a more efficient approach, based on 2-D PAGE, for the detection of variants in DNA, with special reference to the identification of a variant… more

Date: July 15, 1991

Creator: Neel, J.V.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Some properties of the log-Laplace distribution

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: Report

Partner: UNT Libraries Government Documents Department

open access

Life sciences

This document is the 1989--1990 Annual Report for the Life Sciences Divisions of the University of California/Lawrence Berkeley Laboratory. Specific progress reports are included for the Cell and Molecular Biology Division, the Research Medicine and Radiation Biophysics Division (including the Advanced Light Source Life Sciences Center), and the Chemical Biodynamics Division. 450 refs., 46 figs. (MHB)

Date: April 1, 1991

Creator: Day, L.

Item Type: Report

Partner: UNT Libraries Government Documents Department