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Brookhaven highlights for fiscal year 1991, October 1, 1990--September 30, 1991

Description: This report highlights Brookhaven National Laboratory's activities for fiscal year 1991. Topics from the four research divisions: Computing and Communications, Instrumentation, Reactors, and Safety and Environmental Protection are presented. The research programs at Brookhaven are diverse, as is reflected by the nine different scientific departments: Accelerator Development, Alternating Gradient Synchrotron, Applied Science, Biology, Chemistry, Medical, National Synchrotron Light Source, Nuclea… more
Date: January 1, 1991
Creator: Rowe, M.S.; Cohen, A.; Greenberg, D.; Seubert, L. & Kuper, J.B.H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Electrochemistry of Thiobacillus ferrooxidans reactions with pyrite

Description: The objective of this project is to provide the fundamental information on the mechanisms of bacterial leaching of pyrite. The knowledge of how bacterial leaching of pyrite functions is essential for design and development of a technology for coal cleaning with bacteria. The features of major electrochemical techniques will be examined to find out if any of them can provide a diagnostic information on the mechanisms of related reactions.
Date: January 1, 1992
Creator: Pesic, B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Growth regulation by macrophages

Description: The evidence reviewed here indicates that macrophages, either acting alone or in concert with other cells, influence the proliferation of multiple types of cells. Most of the data indicate that these effects are mediated by soluble macrophage-elaborated products (probably proteins) although the role of direct cell-to-cell contacts cannot be ruled out in all cases. A degree of success has been achieved on the biochemical characterization of these factors, due mainly to their low specific activit… more
Date: January 1, 1982
Creator: Wharton, W.; Walker, E. & Stewart, C.C.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Resource capture by single leaves

Description: Leaves show a variety of strategies for maximizing CO{sub 2} and light capture. These are more meaningfully explained if they are considered in the context of maximizing capture relative to the utilization of water, nutrients and carbohydrates reserves. There is considerable variation between crops in their efficiency of CO{sub 2} and light capture at the leaf level. Understanding of these mechanisms indicate some ways in which efficiency of resource capture could be level cannot be meaningfull… more
Date: May 1, 1992
Creator: Long, S.P.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Institutional research and development, FY 1987

Description: The Institutional Research and Development program at Lawrence Livermore National Laboratory fosters exploratory work to advance science and technology, disciplinary research to develop innovative solutions to problems in various scientific fields, and long-term interdisciplinary research in support of defense and energy missions. This annual report describes research funded under this program for FY87. (DWL)
Date: January 1, 1987
Creator: Struble, G. L.; Lawler, G. M.; Crawford, R. B.; Kirvel, R. D.; Peck, T. M.; Prono, J. K. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Biological Production of Ethanol From Coal

Description: The fermentation pH has been observed to be the key parameter affecting the ratio of ethanol to acetate produced by Clostridium ljungdahlii. The effects of controlled pH on cell growth and product formation by C. ljungdahlii were measured. It was found that cell concentration and acetate concentration increased with pH, while the ethanol concentration was highest at the lower pH. The molar product ratio of ethanol to acetate was 0.74 at pH 4.0, 0.39 at pH 4.5 and 0.12 at pH 5.0. Future experime… more
Date: January 1, 1990
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Potential effects of maternal contribution on egg and larva population dynamics of striped bass: Integrated individual-based model and directed field sampling

Description: We have used a bioenergetically-driven, individual-based model (IBM) of striped bass as a framework for synthesizing available information on population biology and quantifying, in a relative sense, factors that potentially affect year class success. The IBM has been configured to simulate environmental conditions experienced by several striped bass populations; i.e., in the Potomac River, MD; in Hudson River, NY; in the Santee-Cooper River System, SC, and; in the San Joaquin-Sacramento River S… more
Date: January 1, 1991
Creator: Cowan, J.H., Jr. (Maryland Univ., Solomons, MD (United States). Chesapeake Biological Lab.) & Rose, K.A. (Oak Ridge National Lab., TN (United States))
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Drug metabolizing enzyme systems and their relationship to toxic mechanisms

Description: The metabolism and toxicity of 3-methylfuran (3-MF) are described. The major product of metabolic activation of 3-MF appears to be disemicarbazones. Cursory description of toxic effects of 3-MF on lung and kidneys are provided. 18 refs.
Date: January 1, 1983
Creator: Boyd, M. R.; Ravindranath, V.; Burka, L. T.; Dutcher, J. S.; Franklin, R. B.; Statham, C. N. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Biological Production of Ethanol From Coal

Description: Research is continuing in an attempt to increase both the ethanol concentration and product ratio using C. ljungdahlii. The purpose of this report is to present data utilizing a medium prepared especially for C. ljungdahlii. Medium development studies are presented, as well as reactor studies with the new medium in batch reactors. CSTRs and CSTRs with cell recycle. The use of this new medium has resulted in significant improvements in cell concentration, ethanol concentration and product ratio.
Date: January 1, 1992
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The bioenergetics of salt tolerance

Description: The aim of this project was to try to understand the adaptive mechanisms that organisms develop in order to respond to a sudden transformation in their environment to a salt shock.'' To study this problem we used a fresh water oxygenic photosynthetic cyanobacterium known as Synecoccus 6311. This organism suffers injury after this sudden exposure to high concentrations of sodium chloride equivalent to or even higher than that in sea water. Yet they are able to re-establish their photosynthetic a… more
Date: January 1, 1991
Creator: Packer, L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Radiation induced micrencephaly in guinea pigs

Description: 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: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Stochastic modelling of physiologic processes with radiotracers and positron emission tomography

Description: The compartment model, so often used in nuclear medicine and in pharmacokinetics, is formed by a set of linear differential equations of order one with constant coefficients; its validity depends upon the hypothesis that the system described contains a finite number of components, and that each component is homogeneous. These hypotheses exclude the presence of diffusion and of age-dependent processes, or in general of transport of a non-Markovian nature. The fact that frequently the experimenta… more
Date: January 1, 1982
Creator: Rescigno, A.; Lambrecht, R. M. & Duncan, C. C.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Research on human genetics in Iceland. Progress report

Description: Records of the Icelandic Population are being used to investigate the possible inheritance of disabilities and diseases as well as other characters and the effect of environment on man. The progress report of research covers the period 1977 to 1980. The investigation was begun in 1965 by the Genetical Committee of the University of Iceland and the materials used are demographic records from the year 1840 to present and various medical information. The records are being computerized and linked t… more
Date: October 31, 1980
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Tumors of the skin and soft tissues

Description: The majority of the body surface is covered by the skin. Many internal disorders are reflected in the condition of the skin. One of the major functions of the skin is protection of the other organ systems from a variety of environmental insults. In this role, the skin itself is exposed to factors that can ultimately cause chronic diseases and cancer. Since it is relatively easy to recognize skin abnormalities, most skin cancers are brought to professional attention sooner than other types of ca… more
Date: October 1, 1991
Creator: Weller, R. E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Comparative mutagenesis of human cells in vivo and in vitro

Description: 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: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Emission computed tomography of /sup 18/F-fluorodeoxyglucose and /sup 13/N-ammonia in stroke and epilepsy

Description: The ECAT Positron Tomograph was used to scan normal control subjects, stroke patients at various times during recovery, and patients with partial epilepsy during EEG monitoring. /sup 18/F-fluorodeoxyglucose (/sup 18/FDG) and /sup 13/N-Ammonia (/sup 13/NH/sub 3/) were used as indicators of abnormalities in local cerebral glucose utilization (LCMR/sub glc/) and relative perfusion, respectively. Hypometabolism, due to deactivation or minimal damage, was demonstrated with the /sup 18/FDG scan in de… more
Date: January 1, 1980
Creator: Kuhl, D. E.; Phelps, M. E. & Engel Jr., J.
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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Purification of phospholamban, a 22,000 dalton protein from cardiac sarcoplasmic reticulum that is specifically phosphorylated by cyclic AMP-dependent protein kinase

Description: Very low concentrations deoxycholate (DOC) were used to isolate two proteins from canine cardiac sarcoplasmic reticulum. These two proteins are phospholamban, a 22,000 dalton protein, and the Ca/sup 2 +/ + Mg/sup 2 +/-ATPase, the major protein of the sarcoplasmic reticulum, responsible for the active transport of calcium. The 22,000 dalton protein is first solubilized in a very low concentration of DOC and then subjected to column chromatography. After molecular weight sieving on a Sephadex G-7… more
Date: January 1, 1979
Creator: Bidlack, J. M. & Shamoo, A. E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Tapered fluidized-bed bioreactor: an improved device for continuous cultivation

Description: The bioreactor concept utilizing a tapered fluidized bed has shown considerable promise for use in bioprocesses where the biological agents can be immobilized on a fluidizable solid phase, but the operating characteristics of such a reactor are not yet fully understood. A simple mathematical model (steady state, plug flow conditions) has been developed and tested with experimental data, and calculated values compare favorably with experimental values. A more complete and presumably more valid m… more
Date: January 1, 1978
Creator: Pitt, Jr., W. W.; Hancher, C. W.; Scott, C. D. & Hsu, H. W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Photoproduction of hydrogen by membranes of green photosynthetic bacteria

Description: Photoproduction of H/sub 2/ from ascorbate by unit-membrane vesicles from Chlorobium limicola f. thiosulfatophilum was achieved with a system containing gramicidin D, tetramethyl-p-phenylenediamine, methyl viologen, dithioerythritol, Clostridium hydrogenase, and an oxygen-scavenging mixture of glucose, glucose oxidase, ethanol, and catalase. Maximum quantum yield was less than one percent. Half maximum rate of H/sub 2/ production occurred at a white-light intensity of approximately 0.15 cm/sup … more
Date: January 1, 1980
Creator: Bernstein, J D & Olson, J M
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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