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Regulation of Meiotic Recombination

Description: Meiotic recombination results in the heritable rearrangement of DNA, primarily through reciprocal exchange between homologous chromosome or gene conversion. In plants these events are critical for ensuring proper chromosome segregation, facilitating DNA repair and providing a basis for genetic diversity. Understanding this fundamental biological mechanism will directly facilitate trait mapping, conventional plant breeding, and development of genetic engineering techniques that will help support… more
Date: November 9, 2011
Creator: Copenhaver, Gregory P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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DEVELOPMENT OF REMOTE HANFORD CONNECTOR GASKET REPLACEMENT TOOLING FOR DWPF

Description: The Defense Waste Processing Facility (DWPF) requested the Savannah River National Laboratory (SRNL) to develop tooling and equipment to remotely replace gaskets in mechanical Hanford connectors to reduce personnel radiation exposure as compared to the current hands-on method. It is also expected that radiation levels will continually increase with future waste streams. The equipment is operated in the Remote Equipment Decontamination Cell (REDC), which is equipped with compressed air, two mast… more
Date: May 5, 2009
Creator: Krementz, D. & Coughlin, Jeffrey
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Hot Dry Rock Geothermal Energy Development Program Annual Report Fiscal Year 1988

Description: The complete list of HDR objectives is provided in Reference 10, and is tabulated below in Tables 1 and 2 for the reader's convenience. The primary, level 1, objective for HDR is ''to improve the technology to the point where electricity could be produced commercially from a substantial number of known HDR resource sites in a cost range of 5 to 8 cents/kWh by 1997''. A critically important milestone in attaining this cost target is the level II objective: ''Evaluate the performance of the Fento… more
Date: January 1, 1988
Creator: Dash, Zora V.; Murphy, Hugh D. & Smith, Morton C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Impact of switching to the ICRP-74 neutron flux-to-dose equivalent rate conversion factors at the Sandia National Laboratory Building 818 Neutron Source Range.

Description: Sandia National Laboratories (SNL) maintains a neutron calibration facility which supports the calibration, maintenance, and repair of Radiation Protection Instruments. The SNL neutron reference fields are calibrated using the following methodology: Fluence rate is initially established by calculation using the NIST traceable source emission rate (decay corrected). Correction factors for the effects of room return or scatter, and source anisotropy are then developed by using a suitable radiatio… more
Date: March 1, 2009
Creator: Ward, Dann C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Optimal recovery sequencing for critical infrastructure resilience assessment.

Description: Critical infrastructure resilience has become a national priority for the U. S. Department of Homeland Security. System resilience has been studied for several decades in many different disciplines, but no standards or unifying methods exist for critical infrastructure resilience analysis. This report documents the results of a late-start Laboratory Directed Research and Development (LDRD) project that investigated the identification of optimal recovery strategies that maximize resilience. To t… more
Date: September 1, 2010
Creator: Vugrin, Eric D.; Brown, Nathanael J. K. & Turnquist, Mark Alan (Cornell University, Ithaca, NY)
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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[News Script: Skylab]

Description: Script from the WBAP-TV/NBC station in Fort Worth, Texas, relating a news story about a meeting held by space officials of the Skylab space center discussing a repair job for a jammed solar panel.
Date: June 4, 1973, 6:00 p.m.
Creator: WBAP-TV (Television station : Fort Worth, Tex.)
Item Type: Refine your search to only Script
Partner: UNT Libraries Special Collections
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Stainless steel submerged arc weld fusion line toughness

Description: This effort evaluated the fracture toughness of austenitic steel submerged-arc weld (SAW) fusion lines. The incentive was to explain why cracks grow into the fusion line in many pipe tests conducted with cracks initially centered in SAWS. The concern was that the fusion line may have a lower toughness than the SAW. It was found that the fusion line, Ji. was greater than the SAW toughness but much less than the base metal. Of greater importance may be that the crack growth resistance (JD-R) of t… more
Date: April 1995
Creator: Rosenfield, A. R.; Held, P. R. & Wilkowski, G. M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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ROBOTIC TANK INSPECTION END EFFECTOR

Description: The objective of this contract between Oceaneering Space Systems (OSS) and the Department of Energy (DOE) was to provide a tool for the DOE to inspect the inside tank walls of underground radioactive waste storage tanks in their tank farms. Some of these tanks are suspected to have leaks, but the harsh nature of the environment within the tanks precludes human inspection of tank walls. As a result of these conditions only a few inspection methods can fulfill this task. Of the methods available,… more
Date: October 1999
Creator: Landry, Rachel
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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[News Script: Auto repairs]

Description: Script from the WBAP-TV/NBC station in Fort Worth, Texas, relating a news story about Dallas attorneys drafting guidelines for new regulations for auto repair shops.
Date: October 31, 1973, 6:30 a.m.
Creator: WBAP-TV (Television station : Fort Worth, Tex.)
Item Type: Refine your search to only Script
Partner: UNT Libraries Special Collections
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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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Cells, targets, and molecules in radiation biology

Description: Cellular damage and repair are discussed with regard to inactivation models, dose-effect curves and cancer research, repair relative to damage accumulation, potentially lethal damage, repair of potentially lethal vs. sublethal damage, cell killing and DNA damage due to nonionizing radiation, and anisotonicity vs. lethality due to nonionizing radiation. Other topics discussed are DNA damage and repair in cells exposed to ionizing radiation, kinetics of repair of single-strand DNA breaks, effects… more
Date: January 1, 1979
Creator: Elkind, M. M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Decreased uv mutagenesis in cdc8, a DNA replication mutant of Saccharomyces cerevisiae

Description: A DNA replication mutant of yeast, cdc8, was found to decrease uv-induced reversion of lys2-1, arg4-17, tryl and ural. This effect was observed with all three alleles of cdc8 tested. Survival curves obtained following uv irradiation in cdc8 rad double mutants show that cdc8 is epistatic to rad6, as well as to rad1; cdc8 rad51 double mutants seem to be more sensitive than the single mutants. Since uv-induced reversion in cdc8 rad1 and cdc8 rad51 double mutants is like that of the cdc8 single mut… more
Date: January 1, 1978
Creator: Prakash, L.; Hinkle, D. & Prakash, S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Photoreactivation in bacteria and in skin

Description: In many procaryotic and eucaryotic cells, photoreactivating enzyme mediates light-dependent repair of uv-induced damage; the enzyme binds to a pyrimidine dimer in DNA, and, on absorption of a photon (300 to 600 nm), specifically monomerizes the dimer, thus repairing the DNA. Photoreactivating enzyme has been found in human tissues and human cells in culture can photoreactivate cellular dimers, and can mediate photoreactivation of Herpes (human fibroblasts) and Epstein-Barr virus (human leukocyt… more
Date: January 1, 1980
Creator: Sutherland, B. M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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uv photobiology: DNA damage and repair

Description: The following topics are discussed: targets that determine the fate of the cell when uv light interacts with a cell; comparison of action spectrum for a given biological effect with the absorption spectrum of different biological macromolecules; biological effects of damage to DNA; measurement of mutations; chemical damage to DNA; photoreactivation; role of pyrimidine dimers in induction of skin cancer by uv. (HLW)
Date: January 1, 1978
Creator: Sutherland, B. M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Mutational repair in mammals and its bearing on risk assessment

Description: Most of the genetic risk from radiation in humans will involve germ cell stages that are of long duration, namely, the spermatogonial stem cells in the male and the oocytes in the female. Mutagenic studies in the mouse that are concerned with risk assessment have, therefore, concentrated on these stages. The first evidence that some repair of mutational damage could occur came from investigations with the specific-locus method in the mouse in which it was shown that when a given dose of radiati… more
Date: January 1, 1977
Creator: Russell, W.L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Mechanisms in endogenous leukemia virus induction by radiation and chemicals

Description: A model of endogenous leukemia virus induction in AKR strain mouse cells based on two distinct types of alterations in cellular or proviral DNA is presented. The first type are non-repairable alterations, such as those caused by the incorporation of halogenated pyrimidines; the second type are repairable lesions, such as those caused by irradiation or certain other chemicals. The production of non-repairable lesions leads to the formation of a stable, proviral state which is dependent upon cell… more
Date: January 1, 1976
Creator: Tennant, R. W.; Rascati, R. J. & Lavelle, G. C.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Repair of DNA treated with. gamma. -irradiation and chemical carcinogens. Progress report, June 1, 1975--January 31, 1976. [MMS, methylnitrosourea, 7-bromomethyl-12-methylbenz(a)-anthracene, Escherichia coli]

Description: Enzymatic mechanisms of DNA repair are under investigation. From E. coli an endonuclease active on apurinic acid has been separated from endonuclease II active on DNA treated with methylmethane sulfonate, methylnitrosourea, 7-bromomethyl-12-methylbenz(a)anthracene and ..gamma..-irradiation. Mutants have been identified for each enzyme. The purification of both enzymes is proceeding and the mechanism of action of endonuclease II which has both an N-glycosidase and a phosphodiester hydrolase acti… more
Date: February 1, 1976
Creator: Goldthwait, D. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Genetics of x-ray induced double strand break repair in saccharomyces cerevisiae

Description: The possible fates of x-ray-induced double-strand breaks in Saccharomyces cerevisiae were examined. One possible pathway which breaks can follow, the repair pathway, was studied by assaying strains with mutations in the RAD51, RAD54, and RAD57 loci for double-strand break repair. In order of increasing radiation sensitivity one finds: rad57-1(23/sup 0/)> rad51-1(30/sup 0/)> rad54-3(36/sup 0/). At 36/sup 0/, rad54-3 cells cannot repair double-strand breaks, while 23/sup 0/, they can. Strains wit… more
Date: July 1, 1982
Creator: Budd, Martin Ellsworth
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Operations, Maintenance, and Replacement 10-Year Plan, 1990 -1999.

Description: In 1988 Bonneville Power Administration (BPA) began work on this Operations, Maintenance, and Replacement 10-Year Plan to develop a levelized program that would assure high system reliability. During the Programs in Perspective (PIP) meetings in the late summer and fall of 1988, many of the concerns to be addressed in an Operations, Maintenance, and Replacement Plan were identified. Following these PIP meetings BPA established internal work groups. During the winter and spring of 1989, these wo… more
Date: August 1990
Creator: United States. Bonneville Power Administration.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Molecular basis for the mutagenic and lethal effects of ultraviolet irradiation. Progress report, December 1, 1977--November 30, 1978. [Micrococcus luteus, Escherichia coli]

Description: Our earlier work on the chemical basis of mutagenesis led to certain chemical generalities necessary to explain how certain mutagens such as UV light and hydroxylamine functioned in information transfer systems (replicative, transcriptive and translational). When such modifications were applied to biologically active DNA in a controlled manner biological expression was non-stoichiometric because much of the damage was removed from the DNA by repair systems. Our efforts were then directed to the… more
Date: July 1978
Creator: Grossman, L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Compensatory Paracrine Mechanisms That Define The Urothelial Response to Injury in Partial Bladder Outlet Obstruction

Description: Diseases and conditions affecting the lower urinary tract are a leading cause of dysfunctional sexual health, incontinence, infection, and kidney failure. The growth, differentiation, and repair of the bladder's epithelial lining are regulated, in part, by fibroblast growth factor (FGF)-7 and -10 via a paracrine cascade originating in the mesenchyme (lamina propria) and targeting the receptor for FGF-7 and -10 within the transitional epithelium (urothelium). The FGF-7 gene is located at the… more
Date: June 21, 2007
Creator: Bassuk, James; Lendvay, Thomas S.; Sweet, Robert; Han, Chang-Hee; Soygur, Tarkan; Cheng, Jan-Fang et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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