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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

Effects of Total Dissolved Gas on Chum Salmon Fry Incubating in the Lower Columbia River

Description: This report describes research conducted by Pacific Northwest National Laboratory in FY 2007 for the U.S. Army Corps of Engineers, Portland District, to characterize the effects of total dissolved gas (TDG) on the incubating fry of chum salmon (Onchorhynchus keta) in the lower Columbia River. The tasks conducted and results obtained in pursuit of three objectives are summarized: * to conduct a field monitoring program at the Ives Island and Multnomah Falls study sites, collecting empirical data on TDG to obtain a more thorough understanding of TDG levels during different river stage scenarios (i.e., high-water year versus low-water year) * to conduct laboratory toxicity tests on hatchery chum salmon fry at gas levels likely to occur downstream from Bonneville Dam * to sample chum salmon sac fry during Bonneville Dam spill operations to determine if there is a physiological response to TDG levels. Chapter 1 discusses the field monitoring, Chapter 2 reports the findings of the laboratory toxicity tests, and Chapter 3 describes the field-sampling task. Each chapter contains an objective-specific introduction, description of the study site and methods, results of research, and discussion of findings. Literature cited throughout this report is listed in Chapter 4. Additional details on the study methdology and results are provided in Appendixes A through D.
Date: January 30, 2008
Creator: Arntzen, Evan V.; Hand, Kristine D.; Geist, David R.; Murray, Katherine J.; Panther, Jenny; Cullinan, Valerie I. et al.
Partner: UNT Libraries Government Documents Department

Using DUSTRAN to Simulate Fog-Oil Dispersion and Its Impacts on Local Insect Populations at Ft. Hood: Final Report

Description: Smokes and obscurants (S&O) are important screening agents used during military training exercises on many military installations. Although the use of S&O is subject to environmental laws, the fate and effects of S&O on natural habitats are not well documented. One particular concern is the impact S&O may have on local insect populations, which can be important components of terrestrial food chains of endangered species. Fog-oil (FO) is an S&O that is of particular concern. An important part of assessing potential ecosystem impacts is the ability to predict downwind FO concentrations. This report documents the use of the comprehensive atmospheric dispersion modeling system DUST TRANsport (DUSTRAN) to simulate the downwind transport and diffusion of a hypothetical FO release on the U.S. Army installation at Ft. Hood, TX.
Date: December 29, 2006
Creator: Rishel, Jeremy P.; Chapman, Elaine G.; Rutz, Frederick C. & Allwine, K Jerry
Partner: UNT Libraries Government Documents Department

Effects of burial by the disposal of dredged materials from the Columbia River on Pacific razor clams (Siliqua patula)

Description: Annual maintenance of the Columbia River navigation channel requires the U.S. Army Corps of Engineers (Corps) to dredge sediment from the river and dispose of the sediment in coastal areas at the mouth of the Columbia River. Some of these disposal areas can be as shallow as 12 m deep in waters off the coastal beaches, and dredged material disposal activities have therefore raised concerns of impacts to local razor clam (Siliqua patula) populations that are prevalent in the area. The Corps’ Portland District requested that the Marine Sciences Laboratory of the U.S. Department of Energy’s Pacific Northwest National Laboratory conduct laboratory experiments to evaluate the potential impacts of burial by dredged material to razor clams during disposal. Prior modeling of disposal events indicates three stresses that could have an impact on benthic invertebrates: convective descent and bottom encounter (compression forces due to bottom impact), dynamic collapse and spreading (surge as material washes over the bottom), and mounding (burial by material). Because the razor clam is infaunal, the effects of the first two components should be minimal, because the clams should be protected by substrate that is not eroded in the event and by the clams’ rapid digging capabilities. The mound resulting from the disposal, however, would bury any clams remaining in the footprint under as much as 12 cm of new sediment according to modeling, and the clams’ reaction to such an event and to burial is not known. Although the literature suggests that razor clams may be negatively affected by siltation and therefore perhaps by dredging and disposal activity, as well, impacts of this type have not been demonstrated. The primary purpose of this study was to evaluate the potential impacts of dredge material disposal on adult subtidal razor clam populations at the mouth of the Columbia River. ...
Date: May 7, 2007
Creator: Vavrinec, John; Kohn, Nancy P.; Hall, Kathleen D. & Romano, Brett A.
Partner: UNT Libraries Government Documents Department

Laboratory Assessment of Potential Impacts to Dungeness Crabs from Disposal of Dredged Material from the Columbia River

Description: Dredging of the Columbia River navigation channel has raised concerns about dredging-related impacts on Dungeness crabs (Cancer magister) in the estuary, mouth of the estuary, and nearshore ocean areas adjacent to the Columbia River. The Portland District, U.S. Army Corps of Engineers engaged the Marine Sciences Laboratory (MSL) of the U.S. Department of Energy’s Pacific Northwest National Laboratory to review the state of knowledge and conduct studies concerning impacts on Dungeness crabs resulting from disposal during the Columbia River Channel Improvement Project and annual maintenance dredging in the mouth of the Columbia River. The present study concerns potential effects on Dungeness crabs from dredged material disposal specific to the mouth of the Columbia River.
Date: May 7, 2007
Creator: Vavrinec, John; Pearson, Walter H.; Kohn, Nancy P.; Skalski, J. R.; Lee, Cheegwan; Hall, Kathleen D. et al.
Partner: UNT Libraries Government Documents Department

A PRIORI PREDICTIVE METHODS OF ASSESSING HEALTH EFFECTS OF CHEICALS IN THE ENVIRONMENT

Description: Passage of the Toxic Substances Control Act (TSCA) last year emphasized the urgent need for the formulation of viable criteria and interim standards limiting the exposure of increasingly large segments of the U.S. population to environmental chemical toxicants. Unfortunately, current methods of developing these standards are both time-consuming and costly. The resulting need for a priori predictive techniques to assess the inherent potential of chemicals, such as the halocarbons found in chlorinated waters, for inducing adverse biological effects, has led to the use of a number of analytical methods designed primarily for screening large numbers of chemical compounds before they impose unacceptable environmental hazards, frequently of crisis proportions. Four of the techniques best adapted to dealing with the multifactorial environmental problems of chemical health effects will be briefly described: (1) quantitative structure/activity relationships (QSAR); (2) factor analysis (FA); (3) pattern recognition/artificial intelligence (PR/AI); and (4) molecular connectivity (MC). While it is clear that none provides easy answers, it would appear that the more recent areas of PR and MC both merit more intensive investigation as predictive tools. In particular, the relative simplicity of the MC approach and the possibility of substantially reducing the empirical component are attractive incentives for pursuing further work in this area.
Date: October 1, 1977
Creator: Kland, M.J.
Partner: UNT Libraries Government Documents Department

Biological effects of underground nuclear testing on marine organisms. II. Observed effects of Amchitka Island, Alaska, tests on marine fauna

Description: >From conference on the environmental effects of explosives and explosions; White Oak, Maryland, USA (30 May 1973). The biological effects of the Longshot, Milrow, and Cannikin underground nuclear tests at Amchitka lsland, Alaska, on marine mammals, fishes, and birds are summarized. The biological effects observed were related to the water-borne shock waves produced by the explosions. (CH)
Date: January 1, 1973
Creator: Isakson, J.S.
Partner: UNT Libraries Government Documents Department

Tolerance of selected fish species to atmospheric gas supersaturation

Description: Several fish species were collected in SE Washington, acclimated to 2O deg C and 100 to 150% gas supersaturation, and exposed to high-gas-content waters (100 to 140% supersaturation) at 20 deg C under standard acute bioassay conditions. The flsh were monitored to determine death time and necropsied to determine the cause of death. The species exhibited a differential tolerance to high gas levels with smallmouth bass more tolerant and salmonids less tolerant. Nearly all fish that died during the test exhibited signs of gas bubble disease, ranging from massive heart embolism to mild subepidermal emphysema. These signs were related to exposure time and to gas supersaturation levels. Gas concentrations were monitored by molecular sieve gas chromatography. (auth)
Date: January 1, 1973
Creator: Fickeisen, D.H.; Montgomery, J.C. & Schneider, M.J.
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