UNT Theses and Dissertations - 27 Matching Results

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Biochemical Genetics of the Pocket Gopher Genus Geomys, and its Phylogenetic Implications

Description: Electrophoretic techniques were utilized for the demonstration of variation in 22 proteins from 24 natural populations of four species ( G. bursarius, G. pinetis, G. arenarius and G. personatus ) of the Geomys complex of pocket gophers. Of the 24 structural loci , 19 were considered to be polymorphic. Five of the six esterases contributed greatested to the polymorphism while non-esterase proteins generally showed low values. In the GeoMys complex of pocket gophers in this study,selection appear… more
Date: December 1974
Creator: Penney, Dan F.
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Biological Nitrogen Fixation in Two Southwestern Reservoirs

Description: This investigation has determined the presence of biological nitrogen fixation in two reservoirs in the southwestern United States: Lake Arlington and Lake Ray Hubbard. Subsequent tests have gathered baseline data on the effects of various biological, chemical, and physical parameters on in situ nitrogen fixation in these reservoirs. Of specific importance is the relationship between nitrogen fixation arid occasional blooms of blue-green algae which produce such problems as testes and odors in … more
Date: August 1973
Creator: Lawley, Gary G.
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Carbon Flux in Reservoir Sediments

Description: The central objective of the study was to fractionate sedimenting organic materials according to their source (allochthonous or autochthonous) and ultimately to determine the degree of biodegradability of contributions from either source with particular reference to activities at the mud-water interface.
Date: May 1973
Creator: Newton, Charles Eugene
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Effect of 2,450 MHz Microwave Radiation on Microorganisms

Description: The effect of microwave radiation on soil bacteria in situ has been studied in both lab and field conditions. Radiation and thermal profiles show that heterotrophic bacteria, spores, fungi, and actinomycetes were not affected by total microwave radiations over the range 0 to 80 seconds of exposure at a net input of 1 KW of intensity. Nitrogen-fixing bacteria and nitrifying bacteria were also resistant to these doses. The soil microorganisms were inactivated as a function of microwave radiation … more
Date: May 1977
Creator: Wu, Jung Fu
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Effects of Carbaryl (1-Naphthyl-n-methylcarbamate) on Trichocorixa Reticulata (Hemiptera: Corixidae) and Glyptotendipes Barbipes (Diptera: Chironomidae)

Description: My study of the effects of carbaryl in aquatic systems under controlled laboratory conditions emphasized four major objectives: (1) to determine the acute toxicity of carbaryl to the herbivorous adult and immature Trichocorixa reticulata (Guerin)(Hemiptera: Corixidae), and to the omnivorous larvae of Glyptotendipes barbipes (Staeger) (Diptera: Chironomidae) under static bioassay; (2) to adapt a quantitative method of analysis for carbaryl in water and whole insect tissue extract; (3) to measure… more
Date: December 1971
Creator: Gash, Stephen L.
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Partner: UNT Libraries
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Effects of Phytohormones on Scenedesmus quadricauda

Description: The literature on the effects of phytohormone on algae is clouded with contradictory reports. Reports have been published which substantiate and deny the effects of phytohormones in enhancing the growth and developmental processes in algae. The overall aim of this study was to investigate the response, if any, of the phytohormones indole-3-acetic acid (IAA), gibberellic acid A3 (GA) and kinetin on the physiology of the green alga, Scenedesmus quadricauda. Results obtained for the uptake of 14^C… more
Date: August 1977
Creator: Alam, Mohammad Ihtisham
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Evolutionary Genetics of Certain Mice of the Peromyscus boylii Species Group

Description: The genetic structure of 49 natural populations of four species (P. attwateri, P. boylii, P. pectoralis, and P. polius) of the Peromyscus boylii species group was analyzed through application of chromosomal and electrophoretic techniques. Chromosomal variation within and among populations of the boylii species group was analyzed from 178 specimens. Electrophoretic techniques were utilized for the demonstration of variation in enzymes and other proteins encoded by structural loci and applied to … more
Date: December 1973
Creator: Kilpatrick, Charles William
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Partner: UNT Libraries
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Food, Feeding Selectivity, and Ecological Efficiencies of Fundulus notatus (Rafinesque) (Osteichthyes; Cyprinodontidae)

Description: This study was made to further define the trophic dynamics of Fundulus notatus by determining its ration composition under natural conditions, measuring feeding selectivity under various laboratory conditions of prey-species composition and availability, and determining the efficiencies with which F. notatus utilizes ingested chironomid larvae.
Date: August 1970
Creator: Atmar, Gerald Legare
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Partner: UNT Libraries
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Identification of Glycine as the Factor in Peptone Which Induces Pleomorphism in Azotobacter Vinelandii

Description: The rigid peptidoglycan layer of the cell wall is responsible for maintaining the structural integrity of bacteria. Antibiotics such as penicillin exert their anti-bacterial effect by inhibiting synthesis of peptodoglycan, and enzymes such as lysozyme destroy cell integrity by hydrolyzing specific bonds in the interior of this macromolecule. Defective cells can no longer withstand the high turgor pressure within the cell because they are no longer protected by a rigid wall and tend to become fr… more
Date: December 1972
Creator: Rosenthal, Raoul Simon
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Partner: UNT Libraries
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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
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In Vivo and In Vitro Transformations of Mouse Tissues from a Murine Lymphosarcoma

Description: The problem with which this investigation is concerned is that of determining the nature of events leading to the change. of normal cells into malignant cells. The design of the study is multi-phasic: (A) to establish the presence or absence of an oncogenic virion, (B) to demonstrate by use of the electron microscopy any ultracellular alteration in malignant or transformed tissues, (C) to investigate the nature of the transforming agent in the murine lymphosarcoma, and (D) to employ various met… more
Date: August 1972
Creator: Carnes, James Edgar
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The Influence of a Return of Native Grasslands upon the Ecology and Distribution of Small Rodents in Big Bend National Park

Description: In the southwestern United States there is a delicate balance between the existing grasslands and the rodent fauna. The purpose of this investigation was to determine the influence of secondary succession of native grasslands upon the ecology and distribution of small rodents. Two methods of determining the rodent species were plot quadrates and trap lines using Sherman live traps.
Date: August 1971
Creator: Baccus, John T.
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The Isolation and Characterization of a Hitherto Undescribed Gram-Negative Bacterium

Description: A unique undosciribed gramnegative rod is extensively characterized in this study. The cells of this unusual water isolate measure 1.2 X 6.5 microns, The most distinguishing characteristic of the bacterium is a polar tuft of 35-40 flagella that aggregate to function as a single organelle which is visible under phase contrast. Aging cells deposit poly- -hydroxybutyric acid granules which are bound by an inclusion membrane made up of four distinct layers. It also possesses an unusual exterior mem… more
Date: August 1972
Creator: Lassiter, Carroll Benson
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Partner: UNT Libraries
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Isolation and Characterization of Malic Enzyme from Ascaris suum

Description: A procedure for the isolation of malic enzyme from muscle tissue of the roundworm Ascaris suum is described. The fractionation method yields relatively large quantities of the enzyme,with a specific activity of fifteen moles of malate converted to pyruvate and carbon dioxide per min per mg at 25º. Homogeneity was established with analytical ultracentrifugation, zone electrophoresis, isoelectric focusing, and rechromatography. The molecular weight of the enzyme was 250,000, and it is dissociated… more
Date: December 1972
Creator: Fodge, Douglas W.
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Partner: UNT Libraries
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Light and Electron Microscope Studies on the Chemotherapeutic Effect of a Combination of Dimethyl Sulfoxide and Hematoxylin on a Transplantable Lymphosarcoma

Description: Investigations concerning the cellular response of tumor tissue to treatment with dimethyl sulfoxide and hematoxylin have not been reported. To establish the response of neoplastic tissue and cells to this combination of agents, this study was undertaken to determine the effects of dimethyl sulfoxide and hematoxylin on a transplantable lymphosarcoma in mice.
Date: January 1970
Creator: Rogers, Thomas D., 1939-
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Partner: UNT Libraries
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Linkage Relationships of Greenbug Resistance in Barley, Hordeum Vulgare L.

Description: The linkage relationship and arm location of the gene for greenbug resistance in the variety Will was determined by using primary trisonomics and tertiary trisomic homozygous translocations. The gene for greenbug resistance was found to be on linkage group 1 by using primary trisonomics. The gene was located on the cetromere segment of the Tl-6a translocation by using a tertiary trismoic homozygous for greenbug resistance. The data further substantiates the feasibility of using trisomics in pla… more
Date: December 1972
Creator: Gardenhire, James H.
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Partner: UNT Libraries
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Microbiological Treatment of Wastewater from a Wood-Preserving Plant

Description: This research investigates interacting biological, chemical, and physical factors affecting the efficiency of microbiological wastewater treatment at the W. J. Smith Wood- Preserving Company in Denison, Texas. The treatment process consisted of collecting exhaust boiler water containing unidentified boiler treatment compounds, steam condensate contaminated with preservatives and wood extracts, plant process waters, and rainfall runoff from plant grounds. With a 5-minute residence time, wastewat… more
Date: August 1974
Creator: Ralston, James R.
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Partner: UNT Libraries
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Odorous Metabolite and Other Selected Studies of Cyanophyta

Description: The purpose of this study was as follows: 1. Elucidate the laboratory conditions under which Anabaena circinalis produces the noxious odor component or components in maximum concentration, 2. Isolate the major noxious odorous metabolite(s), 3. Structurally define the odorous metabolite(s), 4. Quantitate the amount of metabolite(s) that a given amount of the organism produced.
Date: August 1970
Creator: Henley, Don E.
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Partner: UNT Libraries
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Passive Dispersal of Algae and Protozoa Internally and Externally by Selected Aquatic Insects

Description: This investigation was concerned with three aspects of the problem of passive dispersal of algae and protozoa by aquatic insects: the role of odonates in passive dispersal of viable small aquatic organisms, the passage of viable algae and protozoa through digestive tracts of field-collected herbivorous and carnivorous aquatic insects, and the viability duration of selected algae, during insect transport under monitored conditions.
Date: December 1970
Creator: Solon, Bernard M. (Bernard Michael), 1932-
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Population Genetics, Karyology, and Morphology of Certain Species of the Peromyscus Truei Group

Description: The systematic relationship of two species of the Peromyscus truei group (P. truei and P. difficilis) was analysed through the application of starch gel electrophoresis, numerical taxonomy, and chromosomal techiques. Of 20 loci examined, 11 were monomorphic in all populations, two exhibited variation in only two populations, and seven loci were polymorphic in two or more populations. The mean number of polymorphic loci per population was 0.186, the mean number of polymorphic loci per individual… more
Date: May 1976
Creator: Hart, Billy Joe
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Primary Productivity and Nutrient Relationships in Garza-Little Elm Reservoir

Description: A large, multi-basin, reservoir (Garza-Little Elm Reservoir) in north central Texas was studied to determine the relative effects of various parameters on primary productivity. The basins were impounded several years apart,thus allowing the influence of age on water chemistry and biota to be considered. Another principal influence on water quality was secondary sewage effluent that entered one basin from a nearby source.
Date: May 1973
Creator: Smith, Jerry Allen
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Studies on the Morphology and Biology of Cotton Rats (Sigmodon hispidus) from Northern Mexico to Southern Nebraska

Description: This investigation was designed to evaluate the need for retaining both Sigmodon hispidus texianus and Sigmodon hispidus berlandieri as subspecific designations. An attempt was made to demonstrate bioclimatic variation and reproductive seasonality in cotton rats. The validity of applying the results of isolated studies of cotton rat populations to the species as a whole was examined.
Date: December 1971
Creator: Cleveland, Arthur Gordon
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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