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Life History Energetics of The Red-Eared Turtle, Pseudemys scripta in North Central Texas

Description: A population of the red-eared slider, Pseudemys scripta, in north central Texas was studied from 1975 to 1980. A life history energy budget was developed for a typical individual in the population and the population dynamics were estimated. A growth model relating growth rate to mean plastron length (PL) was developed from recapture data and used to 1) establish age classes and 2) age individuals. Growth rate was highly variable in both sexes. Females grew more rapidly than males and attained a… more
Date: December 1984
Creator: Glidewell, Jerry Ray, 1945-
Item Type: Refine your search to only Thesis or Dissertation
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A Study of Polynuclear Aromatic Hydrocarbon Carcinogen Transport and Deoxyribonucleic Acid Repair

Description: This investigation addresses the interrelated problems of A) Uptake and vascular transport of lipophilic chemical carcinogens, and intracellular interactions between lipoproteins and carcinogens; B) Biochemical mechanisms by which polynuclear aromatic hydrocarbon carcinogens inhibit the replicative and repair DNA synthesis in cells. The results observed in this study suggest that ingested benzo(a)pyrene (BaP) enters the gastrointestinal lymphatic drainage sequestered within lymphatic lipoprotei… more
Date: December 1984
Creator: Joe, Cheol O., 1949-
Item Type: Refine your search to only Thesis or Dissertation
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Some Responses of Bacillus subtilis Spores to Glutaraldehyde

Description: Bacillus subtilis (ATCC 19659) were damaged by exposure to various concentrations of glutaraldehyde, as shown by decreased germination rates. The damage caused was repaired or otherwise obviated by the presence of sodium lactate in the holding medium. When two different salts of lactic acid were compared for ability to overcome the effect of glutaraldehyde, it was found that calcium salt of lactate was more effective than the sodium salt. The damage repair system involved l-alanine, lactate and… more
Date: May 1985
Creator: Crum, Morris G. (Morris Glenn)
Item Type: Refine your search to only Thesis or Dissertation
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Aquatic Vegetation Nutrient Budgets and Sedimentation in a Southwestern Reservoir

Description: During four growing seasons, aquatic vascular plant production and distribution were studied in Pat Mayse Lake, Texas, a 2425 hectare oligo-mesotrophic reservoir. The dominant macrophyte population was Myriophyllum spicatum L. Growth rates and regrowth rates of mechanically harvested Myriophyllum beds were found to be dissimilar. Based on estimates of watermilfoil nutrient content, there were insufficient nutrients in the entire population to alter the trophic status of this reservoir should al… more
Date: May 1986
Creator: Clifford, Philip A. (Philip Alan)
Item Type: Refine your search to only Thesis or Dissertation
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Fitness-Related Alterations in Blood Pressure Control: The Role of the Autonomic Nervous System

Description: Baroreflex function and cardiovascular responses to lower body negative pressure during selective autonomic blockade were evaluated in endurance exercise trained (ET) and untrained (UT) men. Baroreflex function was evaluated using a progressive intravenous infusion of phenylephrine HCL (PE) to a maximum of 0.12 mg/min. Heart rate, arterial blood pressure, cardiac output and forearm blood flow were measured at each infusion rate of PE. The reduction in forearm blood flow and concomitant rise in … more
Date: December 1986
Creator: Smith, Michael Lamar, 1957-
Item Type: Refine your search to only Thesis or Dissertation
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Gene Dosage Study on Human Chromosome 22

Description: A gene dosage study was conducted on a rare complete trisomy 22 human fibroblast cell line utilizing three lysosomal enzymes, ∝-iduronidase, ∝-galactosidase B, and arylsulfatase A, whose genes are located on chromosome 22 and two control enzymes, ,β-hexosaminidase A and -- fucosidase, with genes not on chromosome 22. A gene dosage effect was clearly demonstrated for an early passage number of the fibroblasts; however, later passage numbers gave inconclusive results. This study suggests that gen… more
Date: December 1986
Creator: Hinkley, Craig S. (Craig Steven)
Item Type: Refine your search to only Thesis or Dissertation
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New Descriptions, Intraspecific Variation and Systematic Importance of Drumming Behavior in Selected North American Plecoptera

Description: Drumming behavior is described for the first time in 33 North American Plecoptera species, and signals of an additional five species, Pteronarcys pictetii, Acroneuria abnormis, Paragnetina media, Clioperla clio and Isogenoides zionensis, are further detailed. An out-group comparison of behavioral characters in all 104 world species whose drumming is known showed that the behavior is more advanced in the Arctoperlaria Group Systellognatha than in the Group Euholognatha. In general, tapping, mono… more
Date: December 1986
Creator: Maketon, Monchan
Item Type: Refine your search to only Thesis or Dissertation
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An Evaluation of the Short-Term Embryo-Larval and Seven-Day Larval Test Methods for Estimating Chronic Toxicity of Zinc to the Fathead Minnow (Pimephales promelas)

Description: Chronic toxicity of zinc to Pimephales promelas was estimated by conducting replicate static and static-renewal short-term embryo-larval tests and static-renewal seven-day larval tests. The two test methods were highly reproducible. Daily renewal of test solutions had little effect on the toxicity of zinc, however, the stage of development at which exposure was initiated affected the sensitivity of the toxic endpoints measured. The most sensitive and reproducible endpoint in the embryo-larval t… more
Date: May 1987
Creator: Stewart, Susan Michels
Item Type: Refine your search to only Thesis or Dissertation
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Predicting the Site-Specific Bioavailability of Zinc Using the Indicator Species Procedure: A Case Study

Description: National Water Quality Criteria intended to protect aquatic life and their uses from the adverse effects of pollutants may not be appropriate due to site-specific factors that alter chemical bioavailability. The Indicator Species Procedure may be used to derive site-specific criteria in order to account for differences in site-specific bioavailability. This procedure was implemented using zinc for three chemically different site (river) waters. The purpose of this study was to quantify the bioa… more
Date: May 1987
Creator: Parkerton, Thomas F.
Item Type: Refine your search to only Thesis or Dissertation
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Rapid Isolation and Purification of Plasmid DNA Using High Performance Liquid Chromatography

Description: High Performance Liquid Chromatography (HPLC) has been employed as an analytical tool for the purification and separation of nucleic acids. A Nucleogen DEAE 4000-10 weak anion exchange column, prepacked with modified silica gels, was used to purify and separate a number of Escherichia coli plasmids. Plasmid DNAs were extracted by the alkaline lysis method. The cleared lysate was injected directly onto the Nucleogen column, and the peaks were collected, desalted and analysed by gel electrophores… more
Date: May 1987
Creator: Nam, Kiebang
Item Type: Refine your search to only Thesis or Dissertation
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Temperature Tolerance of Freshwater Fish Exposed to Water-Borne Cadmium

Description: Lethal toxicity values (96 h LC50; mg Cd/L) for the test species were similar: Lepomis cyanellus, 11.52; Notropis lutrensis, 6.62; Pimephales promelus, 3.58. However the effects of cadmium concentration and exposure time on temperature tolerance varied between species. Neither cadmium concentration nor exposure time had a significant effect on the CTM of green sunfish. Both cadmium concentration and exposure time had a significant effect on the CTMs of red shiners and fathead minnows. By day 10… more
Date: May 1987
Creator: Carrier, Roxie
Item Type: Refine your search to only Thesis or Dissertation
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Endogenous Nucleotide Pools in Growing Cells of Azotobacter Vinelandii

Description: The objective of this investigation was to examine the changes in the nucleotide pools of Azotobacter vinelandii during the growth cycle. Endogenous ribonucleotides were extracted from A. vinelandii using trichloroacetic acid (TCA; 12% w/v). The 5' mono-, di- and triphosphates of adenine, guanine, uracil and cytosine were separated and quantified by anion-exchange high performance liquid chromatography. Results indicated that the adenylate energy charge of A. vinelandii paralleled the growth ra… more
Date: August 1987
Creator: Lee, Yick-Shun
Item Type: Refine your search to only Thesis or Dissertation
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Neuropharmacological Characteristics of Tolerance for Cocaine Used as a Discriminative Stimulus

Description: The main purpose of this research was to investigate the phenomenon of tolerance to cocaine. Tolerance is operationally defined as a decreased drug effect due to prior history of drug administration. The animal model that was chosen to investigate tolerance to cocaine was the drug discrimination model, which is an animal analogue of human subjective drug effects. In the drug discrimination procedure, animals are trained to emit one behavior when injected with saline. In the present experimen… more
Date: August 1987
Creator: Wood, Douglas M. (Douglas Michael)
Item Type: Refine your search to only Thesis or Dissertation
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Life History Biology of the Desert Nesting Seagull Larus modestus

Description: Gray gulls Larus modestus are unique among birds of northern Chile as the only species nesting in the interior Atacama Desert, and the only seagull nesting far (30 - 100 km) from surface water. During breeding-nesting (August - February) gray gulls congregate on the coast of northern Chile where they feed and initiate courtship. As early as August, breeding pairs commute daily to the inner desert to establish nesting territories, round-trip distances of 60-200 Km. During incubation (30 days) an… more
Date: December 1987
Creator: Guerra Correa, Carlos Guillermo
Item Type: Refine your search to only Thesis or Dissertation
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Teratogenic and Mutagenic Potential of Triethylenemelamine, Ethyl Methanesulfonate, and N-Ethyl-N-Nitrosourea for Causing Fetal Anomalies in Mus Musculus

Description: In five separate experiments, weight-adjusted doses of TEM, EMS, and ENU were injected intraperitoneally into twelve week-old female mice six hours after mating. On day seventeen of gestation, the females were sacrificed and their uterine contents were examined. The effect of each agent was determined by its ability to cause malformations and death to the developing embryos. All treatment groups showed statistically significant elevated levels of malformations in comparison to their correspondi… more
Date: December 1987
Creator: Gans, Murry J. (Murry Joe)
Item Type: Refine your search to only Thesis or Dissertation
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Use of Remote Sensing for Cover Type Interpretation Over the Ray Roberts Reservoir Area

Description: As part of a pre-impoundment study for the Ray Roberts Reservoir Area, Landsat-5 multi-spectral scanner (MSS) imagery was used for cover type interpretation. This research was concerned with analysis techniques for MSS images and a comparison of results obtained using computer assisted interpretatin of MSS images and a comparison of results obtained using computer assisted interpretation of MSS images with those obtained using manual interpretation of false color infrared (CIR) photographs.
Date: December 1987
Creator: Cassidy, Kelly Michela
Item Type: Refine your search to only Thesis or Dissertation
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The Effect of N, N Bis (ethylene)-P (1-adamantyl) Phosphonic Diamide on Rous Sarcoma Virus

Description: The drug, N,N bis (ethylene)-P (1-adamantyl) phosphonic diamide inhibits focus formation of Rous Sarcoma Virus in tissue culture. Transformation of chick cells was inhibited when the drug was added to chick cells prior to infection. The drug did not inhibit the transformation of Normal Rat Kidney Cells infected with RSV, when the cells were grown at non-permissive temperatures and shifted to permissive temperatures upon addition of the drug. Nor did the drug revert cells transformed at permissi… more
Date: March 1988
Creator: McGraw, Thomas L. (Thomas Lee)
Item Type: Refine your search to only Thesis or Dissertation
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Effects of Lysolecithin on Macrophages

Description: The effect of lysolecithin on the macrophage was studied using five macrophage function assays. The results of indicate that lyso lecithin is a macrophage activating agent which causes enhanced cell spreading, increased phagocytosis of sheep erythrocytes, heightened membrane activity in the presence of damaged autologous red blood cells, chemotaxis, and vigorous phagocytosis and intracellular killing of Staphylococcus albus.
Date: May 1988
Creator: Swee, Mei Hua
Item Type: Refine your search to only Thesis or Dissertation
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Niche Structure of an Anole Community in a Tropical Rain Forest within the Choco Region of Colombia

Description: Ten species of anoles at Bajo Calima within the Choco of Western Colombia separate into two principal microhabitat groups: forest species, and those inhabiting openings and edges. The ten anoles further separate according to ground and vegetation dwellers. There is a relation at Bajo Calima between the number of anole species and vegetational structural diversity. Anole diversity within a given macrohabitat is by perch microsite/microclimate heterogeneity. These are the two major ecological dim… more
Date: May 1988
Creator: Castro-Herrera, Fernando
Item Type: Refine your search to only Thesis or Dissertation
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Physiological Responses of Myriophyllum spicatum to Time Varying Exposures of Diquat, 2,4-D and Copper

Description: The physiological responses of Myriophyllum spicatum to 2,4-D, diquat and copper were quantified using a plant tissue viability assay, and daily measures of dissolved oxygen and pH. Correlations of herbicide tissue residues to physiological response measures were determined and the relationship was used to develop exposure-response models. Diquat and copper had a greater effect on plant tissue viability than was observed for 2,4-D. Diquat produced greater reductions in dissolved oxygen concentr… more
Date: May 1988
Creator: Rocchio, Patricia Mary
Item Type: Refine your search to only Thesis or Dissertation
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Production, Location, and Binding of Violacein in Janthinobacterium

Description: Violacein is a purple pigment typically produced by species of Chromobacterium and Janthinobacterium. A soil isolate, identified as Janthinobacterium, was studied. Maximal pigmentation occurred at 250C under aerobic conditions in the Keeble and Cross medium. Intracellular pigment was shown to be located in the cell membrane. Comparision of pigment production and growth curves indicated that violacein is synthesized in the cell and released into the environment possibly as a result of cell lysis… more
Date: May 1988
Creator: Lin, Ying-Chuan
Item Type: Refine your search to only Thesis or Dissertation
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Adenylate Energy Charge Determinations of Soil Bacteria Grown in Soil Extract Medium

Description: The adenylate energy charge values of twenty bacteria isolated from soil and cultured in a medium consisting of soil and distilled water were determined by the luciferin-luciferase bioluminescense method. The purpose of this study was to examine the growth and energy charge values of these organisms in soil extract medium, and to determine what effect the addition of glucose has on their energy charge values. Three of the organisms employed in this study showed energy charge values similar to t… more
Date: August 1988
Creator: Rodriguez, Luis A. (Luis Antonio)
Item Type: Refine your search to only Thesis or Dissertation
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Genetic Differentiation of the Geomys Pocket Gopher Complex of Texas

Description: Genetic variation was analyzed for populations of seven taxa comprising four cytotypes of the Geomys bursarius chromosome complex, including G. b. major, G. b. knoxjonesi, and the Edwards Plateau taxa, G. b. llanensis and G. b. texensis. Genetic relationships of the Edwards Plateau gophers with other taxa and between themselves were examined. Genetic similarity, number of fixed allelic differences, and ectoparasite distribution indicate the Edwards Plateau gophers are a distinct gene pool. Isol… more
Date: August 1988
Creator: Block, Scott B. (Scott Bishop)
Item Type: Refine your search to only Thesis or Dissertation
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Genetic Variation in a Population of the Plains Woodrat Neotoma micropus

Description: Neotoma micropus from Jack County, Texas, were studied over a 9-month period. Loci from blood and saliva were used to determine genetic variation within the population. Deviations from Hardy-Weinberg equilibrium were found at one locus. The average temporal F over all seven loci was 0.040. Genetic structuring was subtle, fluctuated on a seasonal basis, and was due to differential migration or predation on genotypes. Heterozygotes tended to move more than homozygotes, and a greater proportion of… more
Date: August 1988
Creator: Stewart, John E. B. (John Edward Bakos)
Item Type: Refine your search to only Thesis or Dissertation
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