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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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A Floristic Study of the Woody Vegetation of the North American Cross Timbers

Description: This research represents the first systematic collection of the woody plants throughout the Cross Timbers. It provides the first keys to these plants in their vegetative condition, plant descriptions, distribution maps, and some quantitative measurements used for descriptive purposes. Descriptions of the woody plants were constructed as an aid in verification after a specimen has been identified by use of the keys. The measurements given pertain only to the woody plants as they occur in the Cro… more
Date: December 1974
Creator: Harrison, Thieron Pike
Item Type: Refine your search to only Thesis or Dissertation
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A New LC Column for the Separation and the Quantitation of Nucleotides

Description: A new column, Dionex AS4A, (polystyrenedivinylbenzene matrix) used for the separation of ribonucleotides and deoxyribonucleotides for the first time, and previously used for ion analysis was found superior to conventional silica columns because it separates ribonucleotides and deoxyribonucleotides. Resolution of dGTP was not possible with the Dionex column and CTP and GDP often co-eluted. Using conventional silica columns, monophosphates separated from diphosphates and diphosphates from triphos… more
Date: December 1987
Creator: Brock, Patricia C. (Patricia Charlene)
Item Type: Refine your search to only Thesis or Dissertation
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Molecular Cloning and Functional Analysis of Transposable Mercury Resistance Genes Encoded by the OCT Plasmid

Description: Translocation of a 17.1 kilobase region of the OCT plasmid encoding mercury resistance (mer) in Pseudomonas putida was shown to occur in a recombination-deficient host with plasmid PP1 serving as a recipient replicon. The frequency of transposition in Pseudomonas was estimated at 10^3 -10 -^2, but undetectable in Escherichia soli. ' DNA comprising all of mr as well as subregions there of were cloned and subjected to DNA sequence analysis. Like other transposons, mer was found to contain inverte… more
Date: August 1991
Creator: Wang, Chien-Sao
Item Type: Refine your search to only Thesis or Dissertation
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Changes in Heterozygosity Through Time in American Standardbred and American Saddlebred Horses (1960-1990)

Description: Observed and expected heterozygosity (H) levels for ten electrophoretic blood marker loci and expected H for seven red blood cell (RBC) anitgen/antibody loci were examined for 20 years in American Standardbred and 30 years in American Saddlebred horses. Standardbreds were classed by gait, Trotter and Pacer, and evaluated separately in most analyses. 4,404 Trotters and 12,271 Pacers were found to have statistically highly significant losses of mean total observed H through time for the ten elect… more
Date: May 1992
Creator: King, Judith A. (Judith Ann), 1955-
Item Type: Refine your search to only Thesis or Dissertation
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Immunofluorescence as a Method for the Rapid Identification of Streptococcus Faecalis in Water

Description: The development and refinement of FA has been adequately investigated with major emphasis on pathogenic microorganisms. The development of this technique has reduced both the time and number of biochemical tests necessary to identify a diversity of organisms. The organisms included are the protozoans, as described by Goldman (1953 and 1957) and by Ingram (1961), viruses, as reported by Liu (1955a) and Burgdorfer and Lackman (1960a), pathogenic bacteria which have been investigated by Moody, Gol… more
Date: August 1970
Creator: Abshire, Robert Louis
Item Type: Refine your search to only Thesis or Dissertation
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Effects of Long-Term Moderate Ethanol Intake on the Stress Response in Rats

Description: The effect of ethanol on the stress response in rats was examined. Experimental animals were given 0.25 ml of 28 percent ethanol or 0.25 ml of water orally once a day, five days a week, for a period of twelve months and were then subjected to fifteen minute cold stress. Corticosterone levels in ethanol-treated males following stress were significantly lower (22 percent) than in the sham group. Adrenal weights in sham-treated females were significantly higher (15 percent) than in the ethanol gro… more
Date: December 1984
Creator: Williams, Judy L. (Judy Lee)
Item Type: Refine your search to only Thesis or Dissertation
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Biological Control of the Red Imported Fire Ant by the Entomopathogenic Nematode, Steinernema Carpocapsae (Weiser)

Description: Field trials were conducted in 1988 to evaluate the effectiveness of Steinernema (=Neoaplectana) carpocapsae (Weiser) in controlling the fire ant. Infective juveniles (IJ) of the nematode were applied as drench on 235 and 422 mounds, respectively for 2-month summer and 6-week fall evaluation periods. In comparative trials, amidinohydrazone (Amdro) was applied to 249 (summer) and 65 (fall) active mounds, with 245 (summer) and 78 (fall) untreated active as controls. Nematode treatments resulted i… more
Date: August 1989
Creator: Morris, John R. (John Robert), 1949-
Item Type: Refine your search to only Thesis or Dissertation
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Opthalmic Use Of Sodium Cephalothin: An In Vivo Comparison

Description: A rabbit keratoconjunctivities model was used to evaluate ophthalmic formulations containing 1 percent sodium cephalothin in silicon oil, a 1 percent sodium cephalothin aqueous solution, and a 0.3 percent gentamicin sulfate solution. Rabit eyes were inoculated intracorneally with Pseudomonas aeruginosa, Staphylococcus aureus, or Streptococcus pneumoniae, After topical treatment, none of the antibiotic formulations were effective in the P. aeruginosa model; all three showed good activity agains… more
Date: August 1979
Creator: Carney, Gerald R.
Item Type: Refine your search to only Thesis or Dissertation
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Diphenyloxazole Metabolism by Aryl Hydrocarbon Hydroxylase

Description: 2,5-Diphenyloxazole (PPO) was tested as a potential alternate inducer for the aryl hydrocarbon hydroxylase (AHH) system. Its apparent lack. of carcinogenicity and toxicity provide a possible system for investigation of enzyme systems related to chemical carcinogenesis without exposure of the researcher to potent carcinogenic compounds. These studies found PPO to be an inducer of AHH in cultured human lymphocytes. When PPO was utilized as a substrate for the AHH assay system, the major metabolit… more
Date: December 1976
Creator: Abreu, Mary E.
Item Type: Refine your search to only Thesis or Dissertation
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Brain Activity in Rats Exposed to Short-Term External Electrical Fields

Description: The effects of external electric fields (EEF) on brain activity in anesthetized rats were studied. The field strengths used, 9 kV/m and 5 kV/m, both D.C. and A.C. (60Hz) were in the range of those measured beneath current overhead transmission lines. Brain activity was monitored from surface electrodes and from electrodes stereotaxically implanted in the posterior-lateral portion of the hypothalamus. It was found that 9 kV/m and 5 kV/m EEF's both D.C. and A.C. brought about statistically signif… more
Date: May 1985
Creator: Hines, Gregory M. (Gregory Manuel)
Item Type: Refine your search to only Thesis or Dissertation
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The Hypothermic Perfusion of the Isolated Thyroid Gland and Its Release of T₃ And T₄

Description: Investigations have shown that the hypothalamus and pituitary respond to decreases in body temperature by stimulating thyroid release of T_3 and T_4 . This study was designed to bypass the control of the hypothalamus and pituitary gland and investigate the direct effect of temperature on the thyroid gland. Hypothermia was by an in vivo isolated perfusion of the thyroid gland. Radio-immunoassay was used to measure T_3 and T_4 concentrations. Significant increases were observed in animals perfuse… more
Date: December 1976
Creator: Haenke, Richard F.
Item Type: Refine your search to only Thesis or Dissertation
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Nutritional Requirements of Corynebacterium poinsettiae

Description: In a minimal medium supplemented with glucose and yeast extract, the optimum pH for the growth of C. poinsettias was found to be 7.5. The organism requires thiamine, biotin, and pantothenic acid for growth. No absolute requirement was found for any amino acid, purine or pyrimidine although an amino acid mixture was stimulatory. Casamino acids could be substituted for the synthetic amino acid mixture. Yeast extract provided an additional factor(s) necessary for maximal growth. The results sugges… more
Date: December 1983
Creator: Hooshdaran, Farideh
Item Type: Refine your search to only Thesis or Dissertation
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Life History Allocation of Energy to Growth and Reproduction in Gizzard Shad, Dorosoma cepedianum, in North Central Texas

Description: Life history allocation of energy to growth and reproduction was determined for female gizzard shad. Absolute caloric energy allocated to eggs increased with age. The relative amount of production energy directed to reproduction increased with age up to 5 years and then decreased. Seasonal variation in lipids was studied. Quantitative changes occurred in ovarian lipids during the reproductive cycle. Carcass lipids varied seasonally. Age of sexual maturity was 3 years. Delayed maturity is attrib… more
Date: December 1976
Creator: Fagan, Joseph A.
Item Type: Refine your search to only Thesis or Dissertation
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Plasma Ion Concentrations in Selected Fishes from Four North Central Texas Reservoirs with Different Salinities

Description: Mean salinity concentrations in the four reservoirs (Moss, Ray Hubbard, Texoma and Possum Kingdom) ranged from 0.2 ppt in Moss Lake to 2.01 ppt in Possum Kingdom Lake. Reservoir sodium and chloride concentrations were hypotonic to hypertonic to plasma levels in all species. Interspecific differences were seen in ionic concentrations within each reservoir. Total osmotic and sodium concentrations in carp, Cyprinus carpio, were correlated to their concentrations in the reservoirs. No such relation… more
Date: December 1983
Creator: Del Regno, Kenneth J. (Kenneth Joseph)
Item Type: Refine your search to only Thesis or Dissertation
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Properties of Normal Rat Kidney Cells Transformed by a Temperature-Sensitive Mutant (LA31) of Rous Sarcoma Virus

Description: The basis of this investigation is to characterize growth property differences in normal versus virally transformed cells. Using a temperature-sensitive mutant of Rous sarcoma virus, the cells' transformation state is regulated by the growth temperature; at 33°C the cells are transformed, while at 39°C the cells have normal characteristics. The morphology of NRK cells is elongated and fibroblastic; when transformed the cells are rounded. Normal cells grow to a monolayer and stop, while transfor… more
Date: August 1983
Creator: Connolly, John R. (John Robert)
Item Type: Refine your search to only Thesis or Dissertation
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Ethylbromo Acetate as an Olfactory Probe

Description: Olfactory transduction mechanisms are best studied when specific blocking agents are available with which to modify cellular responses to odorant stimulation. This study is an electrophysiological investigation of functional group-specific olfactory acceptor mechanisms using ethylbromo acetate (EtBrAc), a World War I war gas which inhibits olfactory responses to odorant stimulation. The major findings of this investigation show that (1) vaporous EtBrAc is found to be a quick and effective inhib… more
Date: August 1980
Creator: McClure, Fred Leland
Item Type: Refine your search to only Thesis or Dissertation
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Studies on the Purification and Phosphorylation of Phosphofructokinase from Ascaris suum

Description: A new procedure has been developed to concentrate the phosphofructokinase from muscle of Ascaris suum with minimum loss of activity. By utilizing this method, 50 ml fraction was concentrated to a final volume of 3 ml in about 1.5 h without loss in enzyme activity. The concentrated enzyme had a specific activity of 64 units per mg. Ascaris muscle-cuticle was incubated in 50 1M solutions of either acetylcholine, serotonin, y-aminobutyric acid, levamisole, or saline alone. Phosphate analysis of th… more
Date: August 1983
Creator: Kaeini, Mohammad R. (Mohammad Reza)
Item Type: Refine your search to only Thesis or Dissertation
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The Dynamics of a Planktonic Microcrustacean Community in a Small North Central Texas Pond Ecosystem

Description: Seven species of planktonic microcrustacea were identified from the North Texas State University Golf Course Pond. Total adult microcrustacean community density, biomass and biocontent, and seasonal cycles of each species were compared with northern populations. Species diversity and evenness indices were highest in summer and lowest in spring. Variations in microcrustacean density showed a positive correlation with density of phytoplankton. Temperature had a direct effect on metabolic rates of… more
Date: December 1976
Creator: Smith, George Arthur
Item Type: Refine your search to only Thesis or Dissertation
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Circulatory and Respiratory Responses to Cycle Ergometry at Different Pedal Rates

Description: The effects of moderate workload exercise at different pedal rates on circulatory and respiratory parameters were studied. Five subjects performed seven discontinuous constant-load cycle ergometer tests of 30 minutes duration at pedal rates of 40, 50, 60, 70, 80, 90 and 100 rpm. Oxygen uptake and carbon dioxide production were determined by standard open circuit spirometry, while heart rate was recorded by electrocardiograph. The CO₂ rebreathing procedure was administered during the exercise bo… more
Date: May 1991
Creator: Hernandez, Raymundo
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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Effects of N⁶,O²'-Dibutyryl Cyclic Adenosine 3' ,5' Monophosphate on Transformation of Rat Kidney Cells and Chick Embryo Fibroblasts by Wild-Type and Temperature-Sensitive Rous Sarcoma Virus

Description: N^6,O^2' -Dibutyryl cyclic adenosine 3',5'-monophosphate (Bt_2cAMP) was investigated for its effects on various tissue culture cells infected with temperature-sensitive (ts) mutant, LA31 and Bratislava 77 (B77), a wild-type Rous sarcoma virus. Specifically, known parameters of transformation were investigated and a possible site of action has been tenably proposed. The drug Bt_2cAMP was found to have little effect on the transformation related properties of primary chick embryo fibroblasts (CEF… more
Date: December 1983
Creator: Marshall, David A. (David Allen)
Item Type: Refine your search to only Thesis or Dissertation
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Physiological Studies of the Bdellovibrio-Host Interaction

Description: The purpose of this study was to focus attention on the physiology of the bdellovibrio-host interaction and to determine the metabolic requirements for this reaction. Since bdellovibrio is an aerobic organism, direct measurements of respiration, turbidity, and viable cell counts are reliable indications of the metabolic activity of the cells. It was determined that the metabolic requirements for the parasitic interaction are constituents from either metabolically active host cells or cells whi… more
Date: December 1976
Creator: Dunton, Philip J.
Item Type: Refine your search to only Thesis or Dissertation
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Isolation and Partial Characterization of Pigment Mutants of Corynebacterium poinsettie ATCC 9682

Description: Carotenoid pigments were extracted from Corynebacteriuma poinsettiae (wild type) ATCC 9682, and from 108 mutants obtained by exposure of a streptomycin resistant strain of C. poinsettiae to ultra-violet light irradiation and N-methyl- N'-nitro-N-nitrosoguanidine. The pigments were characterized by their absorption maxima, Rf-values, and partition ratios in petroleum ether and methanol. Thin layer chromatography was used to compare pigments of the wild type with those of the mutants. Possible bi… more
Date: August 1980
Creator: Wariso, Benjamin A.
Item Type: Refine your search to only Thesis or Dissertation
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