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in subjects: "63 Radiation, Thermal, And Other Environmental Pollutant Effects On Living Organisms And Biological Materials"  
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Comparative Plutonium-239 Dose Assessment for Three Desert Sites: Maralinga, Australia; Palomares, Spain; and the Nevada Test Site, USA - Before and After Remedial Action

Description: As a result of nuclear weapons testing and accidents, plutonium has been distributed into the environment. The areas close to the sites of these tests and accidental dispersions contain plutonium deposition of such a magnitude that health authorities and responsible officials have mandated that the contaminated areas be protected, generally through isolation or removal of the contaminated areas. In recent years remedial actions have taken place at all these sites. For reasons not entirely clear… more
Date: July 14, 2000
Creator: Church, B. W.; Shinn, J.; Williams, G. A.; Martin, L. J.; O'Brien, R. S. & Adams, S. R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Genetic Analysis of Stress Responses in Soil Bacteria for Enhanced Bioremediation of Mixed Contaminants

Description: The purpose of this project is to provide fundamental knowledge on environment stress response of subsurface bacteria and a radiation-resistant bacterium (Deinococcus radiodurans). This information will be particularly useful in the development of successful bioremediation strategies. These organisms represent two phylogenetically distinct groups of soil bacteria, each of which has specific features of interest for bioremediation. The subsurface bacteria, Sphingomonas spp (Savannah River Site),… more
Date: June 1, 2000
Creator: Wong, Kwong-Kwok
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Monitoring Genetic and Metabolic Potential for In-Situ Bioremediation: Mass Spectrometry

Description: A number of DOE sites are contaminated with dense non-aqueous phase liquids (DNAPLs) such as carbon tetrachloride and trichloroethylene. At many of these sites, microbial bioremediation is an attractive strategy for cleanup, since it has the potential to degrade DNAPLs in situ. A rapid screening method to determine the broad range potential of a site's microbial population for contaminant degradation would greatly facilitate assessment for in situ bioremediation, as well as for monitoring ongoi… more
Date: June 1, 2000
Creator: Buchanan, Michelle V.; Britt, Phillip F.; Doktycz, Mitchel J.; Hurst, Gregory B. & Lidstrom, Mary E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Mechanisms of enhanced cell killing at low doses: Implications for radiation risk

Description: Our overall aim is to gather understanding of the mechanisms underlying low-dose hyperradiosensitivity (HRS) and induced radioresistance (IRR). There is now some direct evidence that this dose-dependent radiosensitivity phenomenon reflects changes in the amount, rate or type of DNA repair, rather than indirect mechanisms such as modulation of cell-cycle progression, growth characteristics or apoptosis. There is also indirect evidence that cell survival-related HRS/IRR in response to single dose… more
Date: June 1, 2000
Creator: Joiner, Michael C.; Johnston, Peter J.; Marples, Brian; Scott, Simon D. & Wilson, George D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Bioavailability of Organic Solvents in Soils: Input into Biologically-Based Dose- Response Models for Human Risk Assessments

Description: The purpose of this study is to determine the bioavailability of organic solvents following dermal exposures to contaminated soil and water. Breath analysis is being used to obtain real-time measurements of volatile organics in expired air following exposure in rats and humans. Rhesus monkeys were used as surrogates for humans in benzene exposures. The exhaled breath data was analyzed using physiologically based pharmacokinetic (PBPK) models to determine the dermal bioavailability of organic so… more
Date: June 1, 2000
Creator: Wester, Ronald C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Adaptive response against spontaneous neoplastic transformation induced by low dose ionizing radiation

Description: This project is being conducted to ascertain the shape of the dose response curve for neoplastic transformation in vitro over the dose range 0.0 to 10 cGy, and how this depends on radiation quality and dose fractionation. Preliminary data already have indicated that at a dose of 1 cGy the induced transformation frequency is less than the spontaneous transformation frequency. The results will be compared with animal and human epidemiological data on the induction of cancer by low doses of radiat… more
Date: June 1, 2000
Creator: Redpath, J. Leslie
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Long Term Risk from Actinides in the Environment: Modes of Mobility

Description: The overall goal of the study is to quantify the mobility of soil actinides from all three modes of mobility: wind erosion, water erosion, and vertical migration. We are conducting a set of studies at DOE facilities where actinide kinetics are of concern, particularly Rocky Flats, Hanford, and WIPP. Wind erosion is being quantified using spatially-distributed aerosol measurements, including finely time-resolved measurements, and will be correlated with meteorological and ground cover conditions… more
Date: June 1, 2000
Creator: Breshears, David D.; Ibrahim, Shawki A.; Hakonson, Thomas E.; Whicker, F. Ward; Whicker, Jeffrey J. & Kirchner, Thomas B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Human Genetic Marker for Resistance to Radiations and Chemicals

Description: The major objective of this project is to understand the genetic basis for resistance of humans to radiations and chemicals. In the fission yeast S. pombe, a gene called rad9 plays a key role in promoting resistance to DNA damaging agents and controlling cell cycle progression after radiation or chemical exposure. This investigation focuses on the characterization of a human homologue of this yeast gene, called HRAD9, with the longterm goal of developing the gene as a genetic marker to predict … more
Date: June 1, 2000
Creator: Lieberman, Howard B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Bioavailability Of Organic Solvents In Soils: Input Into Biologically Based Dose-Response Models for Human Risk Assessments

Description: The purpose of this study is to determine the bioavailability of organic solvents following dermal exposures to contaminated soil and water. Breath analysis is being used to obtain real-time measurements of volatile organics in expired air following exposure in rats and humans. Rhesus monkeys were used as surrogates for humans in benzene exposures. The exhaled breath data was analyzed using physiologically based pharmacokinetic (PBPK) models to determine the dermal bioavailability of organic so… more
Date: December 31, 2000
Creator: Wester, Ronald C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Genetic Analysis of Stress Responses in Soil Bacteria for Enhanced Bioremediation of Mixed Contaminants

Description: In order to realize the full potential of bioremediation, an understanding of microbial community and individual bacterial responses to the stresses encountered at contaminated sites is needed. Knowledge about genetic responses of soil and subsurface bacteria to environmental stresses, which include low nutrients, low oxygen, and mixed pollutants, will allow extrapolation of basic principles to field applications, either using indigenous bacteria or genetically engineered microorganisms. Defini… more
Date: December 31, 2000
Creator: Wong, Kwong-Kwok
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Radiation Effects in Nuclear Waste Materials

Description: This research project is investigating radiation effects in glasses and ceramics at the atomic, microscopic, and macroscopic levels. By using experimental and computer simulation approaches, this research endeavors to develop the underpinning science and models necessary to assess radiation effects on the performance of glasses and ceramics designed for the immobilization of high-level tank waste and nuclear materials. The ultimate objective of this project is to provide the scientific understa… more
Date: June 1, 2000
Creator: Weber, William J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

RADIATION EFFECTS IN NUCLEAR WASTE MATERIALS

Description: The objective of this research was to develop fundamental understanding and predictive models of radiation effects in glasses and ceramics at the atomic, microscopic, and macroscopic levels, as well as an understanding of the effects of these radiation-induced solid-state changes on dissolution kinetics (i.e., radionuclide release). The research performed during the duration of this project has addressed many of the scientific issues identified in the reports of two DOE panels [1,2], particular… more
Date: December 31, 2000
Creator: Weber, William J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Molecular Profiling of Microbial Communities from Contaminated Sources: Use of Subtractive Cloning Methods and rDNA Spacer Sequences

Description: The major objective of the research was to provide appropriate sequences and to assemble a DNA arrays of oligonucleotides to be used for rapid profiling of microbial populations, from polluted areas and from areas of other interest. The sequences to be assigned to the DNA array are chosen from cloned genomic DNA from groundwater at DOE sites containing organic solvents. The sites, Hanford Nuclear Plant and Lawrence Livermore Site 300 (LLNL), have well characterized pollutant histories, which ha… more
Date: June 1, 2000
Creator: Robb, Frank T.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Plant Rhizosphere Effects on Metal Mobilization and Transport

Description: The myriad of human activities including strategic and energy development at various DOE installations have resulted in the contamination of soils and waterways that can seriously threaten human and ecosystem health. Development of efficacious and economical remediation technologies is needed to ameliorate these immensely costly problems. Bioremediation (both plant and microbe-based) has promising potential to meet this demand but still requires advances in fundamental knowledge. For bioremedia… more
Date: December 31, 2000
Creator: Fan, Teresa W.-M; Higashi, Richard M. & Crowley, David E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Linking Molecular Events to Cellular Responses at Low Dose Exposures

Description: The studies proposed in this project are to define thresholds in cell signaling pathways that are required for cellular transformation and may be targeted by low-dose radiation. Defining thresholds in transformation-related signal transduction pathways that are sensitive to low-dose radiation would be an important advancement in risk assessment and could be used to demonstrate nonlinear relationships between low-dose radiation and cancer.
Date: June 1, 2000
Creator: Weber, Thomas J.; Colburn, Nancy H. & Bowman, Michael K.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

DETERMINING SIGNIFICANT ENDPOINTS FOR ECOLOGICAL RISK ANALYS ES

Description: Our interest is in obtaining a scientifically defensible endpoint for measuring ecological risks to populations exposed to chronic, low-level radiation, and radiation with concomitant exposure to chemicals. To do so, we believe that we must understand the extent to which molecular damage is detrimental at the individual and population levels of biological organization. Ecological risk analyses based on molecular damage, without an understanding of the impacts to higher levels of biological orga… more
Date: December 31, 2000
Creator: Hinton, Thomas G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Biological Effects of LLIR and Normal Oxidative Damage: The Same or Different?

Description: Epidemiology alone is insufficient to estimate risks associated with low-level ionizing radiation (LLIR) with confidence. Yet much of the concern in mitigating environmental effects of the ''cold war legacy'' of radiation contamination involves LLIR. For example, a question arises as to how clean a contaminated site needs to be in order to be considered adequately restored. The answer depends in part on the risk associated with residual contamination. Incorporation of radiobiological principles… more
Date: June 1, 2000
Creator: Goodwin, Edwin H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Long-Term Risk From Actinides In The Environment: Modes Of Mobility

Description: The mobility of actinides in surface soils remains a key issue of concern at several DOE facilities in arid and semiarid environments, including Rocky Flats, Hanford, Nevada, Idaho, and Los Alamos. Over the last 50 years, nuclear research and development programs have resulted in releases of plutonium to both on-site and off-site locations. Most of this plutonium and other actinides are currently in soils where it is tightly bound to soil particles (Watters et al. 1983), but these particles the… more
Date: December 31, 2000
Creator: Breshears, David D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Mechanisms Involved in Trichloroethylene-Induced Liver Cancer: Importance to Environmental Cleanup

Description: The project is organized around two interrelated tasks: Task 1 develops the basic dosimetry parameters and provides in vivo data describing the mode of action tumorigenic and for the metabolites of TCE that produce liver cancer in mice, dichloroacetate (DCA) and trichloroacetate (TCA). Early work suggested that TCA was primarily responsible for TCE-induced liver tumor. More recent, mechanistic observations indicated that DCA played a prominent role. Therefore, studies were designed to determine… more
Date: June 1, 2000
Creator: Bull, Richard J. & Thrall, Brian D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Implementation of ANSI 13.36 - Radiation Safety Training for Workers

Description: ''Radiation Safety Training for Workers'' (ANSI 13.36) specifies a process for developing and implementing radiation safety training using performance-based concepts. In general, radiation safety training includes radiological safety policies, fundamental radiological controls, and the technical functions of specific facilities. Actual training, however, can vary significantly from one site to another, depending on the requirements and potential risks associated with the specific work involved.… more
Date: November 18, 2000
Creator: Trinosky, P.A. & Wells, L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Interactive, Computer-Based Training Program for Radiological Workers

Description: Lawrence Livermore National Laboratory (LLNL) is redesigning its Computer-Based Training (CBT) program for radiological workers. The redesign represents a major effort to produce a single, highly interactive and flexible CBT program that will meet the training needs of a wide range of radiological workers--from researchers and x-ray operators to individuals working in tritium, uranium, plutonium, and accelerator facilities. The new CBT program addresses the broad diversity of backgrounds found … more
Date: January 18, 2000
Creator: Trinoskey, P.A.; Camacho, P.I. & Wells, L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Environmental Report 1999 Data Supplement

Description: This Data Supplement to the Lawrence Livermore National Laboratory's (LLNL's) annual ''Environmental Report 1999'' was prepared for the U.S. Department of Energy. The main volume is intended to provide all information on LLNL's environmental impact and compliance activities that is of interest to most readers. The Data Supplement supports main volume summary data and is essentially a detailed data report that provides individual data points, where applicable. Some summary data are also included… more
Date: September 1, 2000
Creator: Larson, J. M.; Biermann, A. H.; Harrach, R. J.; Althouse, P. E.; Bertoldo, N. A.; Blake, R. G. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Environmental Report 1999

Description: Lawrence Livermore National Laboratory (LLNL), a U.S. Department of Energy (DOE) facility operated by the University of California (UC), serves as a national resource of scientific, technical, and engineering capabilities. The Laboratory's mission focuses on nuclear weapons and national security, and over the years has been broadened to include areas such as strategic defense, energy, the environment, biomedicine, technology transfer, the economy, and education. The Laboratory carries out this … more
Date: September 1, 2000
Creator: Larson, J. M.; Biermann, A. H.; Harrach, R. J.; Althouse, P. E.; Bertoldo, N. A.; Blake, R. G. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Cloud-Resolving Model Intercomparison with the ARM Summer 1997 IOP Data

Description: The Atmospheric Radiation Measurement (ARM) Program's Single Column Model (SCM) working group conducted its intercomparison study of midlatitude summertime continental convection using the July 1995 Intensive Operational Period (IOP) data set (Ghan et al. 2000). Only one cloud-resolving model (CRM) participated in the study. On the other hand, several CRMs participated in the GEWEX (Global Energy and Water-cycle Experiment) Cloud System Study (GCSS) Working Group 4's intercomparison study of tr… more
Date: March 13, 2000
Creator: Xu, K. M.; Johnson, D. E.; Tao, W. K.; Krueger, S. K.; Khairoutdinov, M.; Randall, D. A. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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