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Individual, Social, and Seasonal Behavior of the Thirteen-Lined Ground Squirrel (Spermophilus tridecemlineatus)

Description: The purpose of this study is to provide a qualitative, detailed description of individual and social behavior in a free-living population of thirteen-lined ground squirrels. Behavioral differences in relation to various periods of the annual cycle are also evaluated.
Date: January 1970
Creator: Wistrand, Harry E.
Item Type: Refine your search to only Thesis or Dissertation
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A Characterization of Liver Glyoxalase I From Normal Mice and Mice Bearing Lymphosarcoma

Description: The purpose of this investigation was (1) to isolate and purify glyoxalase I from the livers of normal DBA/lJ mice and the livers from mice bearing a lymphosarcoma tumor; and (2) to determine, at least with respect to glyoxalase I, if the tumor has an effect on the chemical properties or structure of macromolecules in an organ removed from tumor locale and not histologically affected by its presence.
Date: August 1970
Creator: Strzinek, Robert Alfred
Item Type: Refine your search to only Thesis or Dissertation
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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
Item Type: Refine your search to only Thesis or Dissertation
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Mixed Culture of Chlorella Pyrenoidosa TX71105 and a Variant Strain of Bacillus Megaterium

Description: Very little work has been done on bacteria capable of significantly inhibiting algal growth. This thesis reports the research on mixed cultures of a high-temperature strain of algae, Chlorella pyrenoidosa TX71105, and an organism isolated from the air and tentatively identified as a variant strain of Bacillus megaterium.
Date: August 1970
Creator: Yao, Raymond Che-Fong
Item Type: Refine your search to only Thesis or Dissertation
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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.
Item Type: Refine your search to only Thesis or Dissertation
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Obligately Thermophilic Nitrogen-Fixation in Some Soil Bacteria

Description: In the work presented here, it is claimed that bacteria have been isolated which are capable of growth at high temperatures utilizing molecular nitrogen as their sole nitrogen source. Soil bacteria were isolated which grew at 55 C in nitrogen-free media. They were found to be obligatory thermophiles in nitrogen-free media and facultative thermophiles in media containing organically bound nitrogen.
Date: August 1971
Creator: Milam, Mary
Item Type: Refine your search to only Thesis or Dissertation
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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.
Item Type: Refine your search to only Thesis or Dissertation
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Some Effects of Electrostatic Fields on Brain Activity in Rats

Description: This study concerned the effects of short-term exposures to continuous (10 kv/meter) and pulsed 20 volts at 640 cps/100 msecs) electrostatic fields on the EEG recorded from external electrodes and hypothalamic activity recorded from implanted electrodes in rats. Each experiment lasted at least 90 minutes. The total energies of the waveforms recorded were integrated and printed out for plotting and analysis. Besides the brain activity, the ECG, respiration, and temperature of the animals were al… more
Date: December 1971
Creator: McCain, Harry B.
Item Type: Refine your search to only Thesis or Dissertation
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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
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X-irradiation Effects on the Action Potentials of Frog Sciatic Nerves Inhibited by Carbon Monoxide and Ouabain

Description: The response of frog sciatic nerve action potentials to x-irradiation and metabolic (carbon monoxide) or transport (ouabain) inhibition was determined in an attempt to further identify the nature of radiation insult to nervous tissue. Carbon monoxide, ouabain (2 X 10-5 M), and nitrogen anoxia were shown to produce a near linear decline in action potential amplitude. The carbon monoxide and nitrogen inhibitions of activity were reversible in air; the carbon monoxide inhibition was light reversib… more
Date: December 1971
Creator: Thompson, Wesley J.
Item Type: Refine your search to only Thesis or Dissertation
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Effect of Indole-3-Acetic Acid on the Nucleic Acids of Synchronous Cultures of Chlorella Pyrenoidosa

Description: It was the purpose of this study to investigate the effect of various concentrations of IAA on the nucleic acids of Chlorella pyrenoidosa TX 7-11-05. The time during the life cycle when the greatest effect occurred was investigated by the use of synchronous cultures.
Date: May 1972
Creator: Peterson, James Arthur
Item Type: Refine your search to only Thesis or Dissertation
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Effects of a Methylcholanthrene-Induced Lymphosarcoma on the Blood of DBA/1J Mice

Description: This investigation was concerned with characterizing a tumor line induced and maintained in this laboratory. Various chemical assays, cell counts, and electron microscopy were the methods employed to characterize the blood of mice bearing the tumor at days 3, 6, 9, and 12 after injection of the 1.2 x 10^8 tumor cells.
Date: May 1972
Creator: Lindsey, Jerri Kay
Item Type: Refine your search to only Thesis or Dissertation
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Some Acute Effects of X-Irradiation (LD100) on Plasma and Adrenal Tissue Histamine in Rats

Description: The effects of a lethal dose (1380 r) of X-irradiation on plasma and adrenal tissue histamine levels of rats were studied. The plasma histamine response was triphasic (increase at 1-3 hours, decrease at 5 and 9 hours and return to control at 24 hours post-irradiation). The adrenal tissue histamine response was found to be biphasic (decrease at 1 to 9 hours and a return to control level at 24 hours post-irradiation).
Date: May 1972
Creator: Ferguson, James L.
Item Type: Refine your search to only Thesis or Dissertation
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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
Item Type: Refine your search to only Thesis or Dissertation
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Lipids and Phospholipase Activity of Vibrio Cholerae

Description: One purpose of this investigation is to determine the fatty acid and lipid content of typical Vibrio cholerae cells. The comparison of cholera lipid constituents with those of closely-related bacteria might be of taxonomic value. Furthermore, chemical characterization of the cholera vibrio could provide useful criteria for identification of these disease-producing microorganisms.
Date: August 1972
Creator: Brian, Buford Leo
Item Type: Refine your search to only Thesis or Dissertation
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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
Item Type: Refine your search to only Thesis or Dissertation
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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.
Item Type: Refine your search to only Thesis or Dissertation
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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.
Item Type: Refine your search to only Thesis or Dissertation
open access

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
Item Type: Refine your search to only Thesis or Dissertation
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