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Syntheses of Antimetabolites

Description: In these studies several different types of antimetabolites were synthesized, and their biological effects were examined in various assay systems. More extensive investigations were done in microbial systems in which many of the compounds proved to be inhibitory to growth, and attempts were made to determine the mode of biochemical action by adding supplements of the appropriate natural metabolite.
Date: January 1970
Creator: Clifton, George Gil
Partner: UNT Libraries

Mechanisms of immunosuppression and cellular mechanisms of secondary disease. Final report, September 1, 1971--August 31, 1973

Description: The development of antibody-producing cells was studied in vivo and in vitro using radiation, anti-tumor drugs, and antibiotics. The mechanism of action of phenothiazines was studied at the cellular level using a cell separation technique. The effects of puromycin and purine antimetabolites on the various development stages of cells were studied. (HLW)
Date: January 1, 1973
Creator: Uyeki, E M
Partner: UNT Libraries Government Documents Department

Report of Flood, Oil Sheen, and fish Kill Incidents on East Fork Poplar Creek at the Oak Ridge Y-12 Plant

Description: Water quality and plant opemtion irriiormation provided by the Y-12 Plant strongly suggest that a dechlorinating agent, applied to the raw water released below the North-South Pipes was responsible for the toxicity resulting in the fish kill of July 24. Dissolved oxygen (DO) measurements in upper EFPC indicai e that low oxygen levels (3-5 ppm) occurred for a period of up to 30 min. This slug of low DO water traveling down EFPC to the lake could easily explain the massive fish kill and the resulting observations. Dissolved oxygen levels of 5.2 ppm or lower are documented as causing problems for warmwater fish species (Heath 1995). The presence of other stressors, including a range of petrochemicals, tends to lower resistance to low oxygen conditions. Given the sequence of events in upper EFPC in the few days prior to July 24, where extremely high flows were followed by inputs of a wide range of low concentrations of oils, the sensitivity to low DO conditions might be heightened. The possible toxic impact of ::he oils and other contaminants reaching EFPC as a result of the heavy rainfidl on July 22 doesn't appear significant enough to be the sole cause of the kill on July 24. Even during the height of the kill, a large school of fish remained immediately downstream of the North-South Pipes. If the toxicity of waters flowing through this outlet were the primary cause of the kill, then it would be expected that this school of fish would not have been present immediately below the pipes. Any impact of waters entering from other sources, such as pumping of basements WOUIC1 have produced a staggered pattern of mortality, with fishing dying in different localities at different times and rates. Further, it would be expected that the morta.lhy observed would have ...
Date: September 1, 1997
Creator: Skaggs, B.E.
Partner: UNT Libraries Government Documents Department

Molecular dosimetry of chemical mutagens: measurement of molecular dose and DNA repair germ cells

Description: Molecular dosimetry in the germ cells of male mice is reviewed with regard to in vivo alkylation of sperm heads, in vivo alkylation of sperm DNA, and possible alkylation of sperm protamine. DNA repair in male germ cells is reviewed with regard to basic design of experiments, DNA repair in various stages of spermatogenesis, effect of protamine on DNA repair following treatment with EMS or x radiation, and induction of DNA repair by methyl methanesulfonate, propyl methanesulfonate, and isopropyl methanesulfonate. (HLW)
Date: January 1, 1975
Creator: Sega, G.A.
Partner: UNT Libraries Government Documents Department

The effect of elevated carbon dioxide on a Sierra-Nevadan dominant species: Pinus ponderosa

Description: The impact of increasing atmospheric C0{sub 2} has not been fully evaluated on western coniferous forest species. Two year old seedlings of Pinusponderosa were grown in environmentally controlled chambers under increased C0{sub 2} conditions for 6 months. These trees exhibit morphological, physiological, and biochemical alterations when compared to our controls. Analysis of whole plant biomass distribution has shown no significant effect to the root to shoot ratios, however needles subjected to elevated C0{sub 2} exhibited an increased overall specific needle mass and a decreased total needle area. Morphological changes at the needle level included decreased mesophyll to vascular tissue 91 ratio and variations in starch storage in chloroplasts. The elevated CO{sub 2} increased internal CO{sub 2} concentrations and assimilation of carbon. Biochemical assays revealed that ribulose-bisphosphate carboxylase specific activities increased on per unit area basis with C0{sub 2} treatment levels. Sucrose phosphate synthase (SPS) activities exhibited an increase of 55% in the 700 uL L{sup {minus}1} treatment. These results indicate that the sink-source relationships of these trees have shifted carbon allocation toward above ground growth, possibly due to transport limitations.
Date: January 1, 1995
Creator: Pushnik, J.C.; Demaree, R.S.; Flory, W.B.; Bauer, S.M.; Houpis, J.L.J. & Anderson, P.D.
Partner: UNT Libraries Government Documents Department

Initial studies to assess microbial impacts on nuclear waste disposal

Description: The impacts of the native and introduced bacteria on the performance of geologic nuclear waste disposal facilities should be evaluated because these bacteria could promote corrosion of repository components and alteration of chemical and hydrological properties of the surrounding engineered and rock barriers. As a first step towards investigating these potentialities, native and introduced bacteria obtained from post-construction Yucca Mountain (YM) rock were isolated under varying conditions, including elevated temperature, low nutrient availability, and the absence of available oxygen. Individual isolates are being screened for activities associated with microbially induced corrosion of metals (MIC). Preliminary determination of growth rates of whole YM microbial communities under varying conditions was also undertaken.
Date: February 20, 1996
Creator: Horn, J.M.; Meike, A.; McCright, R.D. & Economides, B.
Partner: UNT Libraries Government Documents Department

Lower Columbia River Terminal Fisheries Research Project : Final Environmental Assessment.

Description: This notice announces BPA`S`s decision to fund the Oregon Department of Fish and Wildlife (ODFW), the Washington Department of Fish and Wildlife (WDFW), and the Clatsop Economic Development Committee for the Lower Columbia River Terminal Fisheries Research Project (Project). The Project will continue the testing of various species/stocks, rearing regimes, and harvest options for terminal fisheries, as a means to increase lower river sport and commercial harvest of hatchery fish, while providing both greater protection of weaker wild stocks and increasing the return of upriver salmon runs to potential Zone 6 Treaty fisheries. The Project involves relocating hatchery smolts to new, additional pen locations in three bays/sloughs in the lower Columbia River along both the Oregon and Washington sides. The sites are Blind Slough and Tongue Point in Clatsop County, Oregon, and Grays Bay/Deep River, Wahkiakum County, Washington. The smolts will be acclimated for various lengths of time in the net pens and released from these sites. The Project will expand upon an existing terminal fisheries project in Youngs Bay, Oregon. The Project may be expanded to other sites in the future, depending on the results of this initial expansion. BPA`S has determined the project is not a major Federal action significantly affecting the quality of the human environment, within the meaning of the National Environmental Policy Act (NEPA) of 1969. Therefore, the preparation of an environmental impact statement is not required, and BPA`S is issuing this FONSI.
Date: April 1, 1995
Creator: United States. Bonneville Power Administration.
Partner: UNT Libraries Government Documents Department

Small mammal study of Sandia Canyon, 1994 and 1995

Description: A wide range of plant and wildlife species utilize water discharged from facilities at Los Alamos National Laboratory (LANL). The purpose of this study was to gather baseline data of small mammal populations and compare small mammal characteristics within three areas of Sandia Canyon, which receives outfall effluents from multiple sources. Three small mammal trapping webs were placed in the upper portion of Sandia Canyon, the first two were centered in a cattail-dominated marsh with a ponderosa pine overstory and the third web was placed in a much drier transition area with a ponderosa pine overstory. Webs 1 and 2 had the highest species diversity indices with deer mice the most commonly captured species in all webs. However, at Web 1, voles, shrews, and harvest mice, species more commonly found in moist habitats, made up a much greater overall percentage (65.6%) than did deer mice and brush mice (34.5%). The highest densities and biomass of animals were found in Web 1 with a continual decrease in density estimates in each web downstream. There is no statistical difference between the mean body weights of deer mice and brush mice between sites. Mean body length was also determined not to be statistically different between the webs (GLM [deer mouse], F = 0.89, p = 0.4117; GLM [brush mouse], F = 2.49, p = 0.0999). Furthermore, no statistical difference between webs was found for the mean lean body masses of deer and brush mice (GLM [deer mouse], F = 2.54, p = 0.0838; GLM [brush mouse], F = 1.60, p = 0.2229). Additional monitoring studies should be conducted in Sandia Canyon so comparisons over time can be made. In addition, rodent tissues should be sampled for contaminants and then compared to background or control populations elsewhere at the Laboratory or at an off-site ...
Date: November 1, 1996
Creator: Bennett, K. & Biggs, J.
Partner: UNT Libraries Government Documents Department

Ultrasound: Biological Effects and Industrial Hygiene Concerns

Description: This paper discusses biological effects associated with overexposure to ultrasound, exposure standards proposed for airborne and contact ultrasound, industrial hygiene controls that can be employed to minimize exposure, and the instrumentation that is required for evaluating exposures.
Date: December 3, 1984
Creator: Wiernicki, C.
Partner: UNT Libraries Government Documents Department

Laboratory and Field Evidence for Long-Term Starvation Survival of Microorganisms in Subsurface Terrestrial Environments

Description: BIOGEOCHEMICAL MODELING OF GROUNDWATER FLOW AND NUTRIENT FLUX IN SUBSURFACE ENVIRONMENTS INDICATES THAT INHABITANT MICROORGANISMS EXPERIENCE SEVERE NUTRIENT LIMITATION. USING LABORATORY AND FIELD METHODS, WE HAVE BEEN TESTING STARVATION SURVIVAL IN SUBSURFACE MICROORGANISMS. IN MICROCOSM EXPERIMENTS, WE HAVE SHOWN THAT STRAINS OF TWO COMMONLY ISOLATED SUBSURFACE GENERA, ARTHROBACTER AND PSEUDOMONAS, ARE ABLE TO MAINTAIN VIABILITY IN LOW-NUTRIENT, NATURAL SUBSURFACE SEDIMENTS FOR OVER ONE YEAR. THESE NON-SPORE-FORMING BACTERIA UNDERGO RAPID INITIAL MINIATURIZATION FOLLOWED BY A STABILIZATION OF CELL SIZE. MEMBRANE LIPID PHOSPHOLIPID FATTY ACID (PLFA) PROFILES OF THE PSEUDOMONAS ARE CONSISTENT WITH ADAPTATION TO NUTRIENT STRESS; ARTHROBACTER APPARENTLY RESPONDS TO NUTRIENT DEPRIVATION WITHOUT ALTERING MEMBRANE PLFA. TO TEST SURVIVABILITY OF MICROORGANISMS OVER A GEOLOGIC TIME SCALE, WE CHARACTERIZED MICROBIAL COMMUNITIES IN A SEQUENCE OF UNSATURATED SEDIMENTS RANGING IN AGE FROM MODEM TO {gt}780,000 years. Sediments were relatively uniform silts in Eastern Washington State. Porewater ages at depth (measured by the chloride mass-balance approach) were as old as 3,600 years. Microbial abundance, biomass, and activities (measured by direct counts, culture counts, total PLFAs, and radiorespirometry) declined with sediment age. The pattern is consistent with laboratory microcosm studies of Microbial survival: rapid short-term change followed by long-term survival of a proportion of cells. Even the oldest sediments evinced a small but viable Microbial community. Microbial survival appeared to be a function of sediment age. Porewater age appeared to influence the markup of surviving communities, as indicated by PLFA profiles. Sites with different Porewater recharge rates and patterns of Pleistocene flooding had different communities.
Date: December 31, 1997
Creator: Kieft, T.L.; Murphy, E.M.; Amy, P.S.; Haldeman, D.L. & Ringelberg, D. B.
Partner: UNT Libraries Government Documents Department

Physiological ecology of SRS Carolina bay phytoplankton communities: Effects of nutrient changes and CO{sub 2} sources

Description: Impacts of land-use activities on wetland ecosystems are important issues for environmental planners, conservation groups, and government agencies. The progress report of this project at DOE`s Savannah River Site focused on two specific objectives: determination of the effects of nutrient enrichment (fertilizing during wetlands restoration) on phytoplankton communities and comparison of phytoplankton community dynamics during the current extended hydroperiod for Carolina Bays with patterns in previous drier years.
Date: November 1, 1992
Creator: Williams, J.B.
Partner: UNT Libraries Government Documents Department

ELEVATED CO{sub 2} IN A PROTOTYPE FREE-AIR CO{sub 2} ENRICHMENT FACILITY AFFECTS PHOTOSYNTHETIC NITROGEN RELATIONS IN A MATURING PINE FOREST

Description: A maturing loblolly pine (Pinus taeda L.) forest was exposed to elevated CO{sub 2} in the natural environment in a perturbation study conducted over three seasons using the free-air CO{sub 2} enrichment (FACE) technique. At the time measurements were begun in this study, the pine canopy was comprised entirely of foliage which had developed under elevated CO{sub 2} conditions (atmospheric [CO{sub 2}] {approx} 550 {micro}mol mol{sup {minus}1}). Measurements of leaf photosynthetic responses to CO{sub 2} were taken to examine the effects of elevated CO{sub 2} on photosynthetic N nutrition in a pine canopy under elevated CO{sub 2}. Photosynthetic CO{sub 2} response curves (A-c{sub i} curves) were similar in FACE trees under elevated CO{sub 2} compared with counterpart trees in ambient plots for the first foliage cohort produced in the second season of CO{sub 2} exposure, with changes in curve form detected in the foliage cohorts subsequently produced under elevated CO{sub 2}. Differences in the functional relationship between carboxylation rate and N{sub a} suggest that for a given N{sub a} allocated among successive cohorts of foliage in the upper canopy, V{sub c max} was 17% lower in FACE versus Ambient trees. The authors also found that foliar Rubisco content per unit total protein derived from Western blot analysis was lower in late-season foliage in FACE foliage compared with ambient-grown foliage. The results illustrate a potentially important mode of physiological adjustment to growth conditions that may operate in forest canopies. Their findings suggest that mature loblolly pine trees growing in the field may have the capacity for shifts in intrinsic nitrogen utilization for photosynthesis under elevated CO{sub 2} that are not dependent on changes in leaf N. While carboxylation efficiency per unit N apparently decreased under elevated CO{sub 2}, photosynthetic rates in trees at elevated CO{sub 2} concentrations {approx} 550 pmol mol{sub ...
Date: March 1, 1998
Creator: ELLSWORTH,D.S.; LA ROCHE,J. & HENDREY,G.R.
Partner: UNT Libraries Government Documents Department

A STUDY OF FISCHER 344 RATS EXPOSED TO SILICA DUST AT CONCENTRATIONS OF 0, 2, 10 OR 20 MG/M3, THEN MAINTAINED FOR SIX MONTHS PRIOR TO ASSESSMENT.

Description: The major objective of this study was to relate the results of a series of functional tests to the compositional and structural alterations in the rat lung induced by subchronic exposure to silica dust. To induce a fibrotic lesion, Fischer-344 rats were exposed to either 0, 2, 10, or 20 mg Si0{sub 2}/m{sup 3} for 6 hours/day, 5 days/week for six months and then maintained in an animal room, equipped with a laminar flow unit, for six months prior to assessment of the end points.
Date: November 1, 1984
Creator: KUTZMAN,R.S.
Partner: UNT Libraries Government Documents Department

Evaluating the risk of air pollution to forests in central and Eastern Europe

Description: Foliar damage to trees by air pollution in Central and Eastern Europe has been a major scientific and political issue. Emissions of toxic gases such as sulfur dioxide and nitrogen oxides can have wide-ranging effects on local and regional vegetation that can be compounded by other environmental stresses to plant growth. Since uptake and physiological effects of these gases on tree leaves we largely, mediated by stomata, surrogate methods for estimating pollutant conductances into leaves and forest canopies may lead to risk assessments for major vegetation types that can then be used in regional planning. Management options to ameliorate or mitigate air pollutant damage to forests and losses in productivity are likely to be more difficult to widely implement than on-the-stack emissions abatement. Informed management and policy decisions regarding Central and Eastern European forests are dependent on the development of quantitative tools and models for risk assessment of the effects of atmospheric pollutants on ecosystem health and productivity.
Date: September 1, 1996
Creator: Ellsworth, D.S. & Oleksyn, J.
Partner: UNT Libraries Government Documents Department