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Spring Food Habits of Corydalus Cornutus L. in the Brazos River, Texas

Description: The objective of this study was to determine the kinds and numbers of food organisms consumed by Corydalus cornutus, and to investigate its periodicity of feeding during the spring months in the Brazos River, Palo Pinto County, Texas. A total of 468 larvae were collected at two-week intervals from February 29 to May 14, 1971. Larvae were taken at opportunity during three periods of the day, 6am.-12pm., 12pm.-6pm., and 6pm.-12am. A total of 23 different food items was observed in the 121 stomachs containing food. An expedient method of dissection of the digestive tract is included.
Date: August 1971
Creator: Friday, Gary P.
Partner: UNT Libraries

An Ecological Study of the Pine Vole, Microtus Pinetorum, in Northeast Texas

Description: This study dealt with the life history and population dynamics of the pine vole, Microtus pinetorum. In the past there has been a void of ecological material concerning this small mammal in the southwestern region of its range. From November, 1969, through February, 1970, a survey was conducted in Marion County and Harrison County, Texas, to determine the most suitable habitat for an ecological study of Microtus pinetorum. A study was then initiated in March, 1970, and continued through March, 1971, on an undisturbed marsh five miles south of Marshall, Harrison County, Texas.
Date: August 1971
Creator: Greer, Roy E.
Partner: UNT Libraries

Isolation and Partial Characterization of Carotenoid Pigments of Mycobacterium Rhodochrous

Description: It was the purpose of this investigation to isolate and characterize the pigments of Mycobacterium rhodochrous by partition behavior, chromatographic data, and absorption spectra. In addition, it was the purpose to determine whether or not the type of pigments found in M. rhodochrous is typical of those found in other mycobacteria.
Date: August 1971
Creator: Jorgensen, Joyce A.
Partner: UNT Libraries

Effects of X-Irradiation of Respiration in Frog Brain Tissue Slices Using the Oxygen Electrode Method

Description: The effects of X-irradiation at dosages of 40 r, 80 r, 160 r, 240 r, 320 r, 400 r, 800 r, 4 Kr, 8 Kr, and 16 Kr on the oxygen uptake of frog brain (Rana pipiens) tissue slices were studied. A membrane-covered oxygen electrode method was used to measure the respiratory rate. Continuous recordings were made before, during, and following X-irradiation in all of the test experiments. X-irradiation was delivered from a G. E. beryllium window X-ray unit at 120 KVP, 5 ma with a 1/4 mm Al filter.
Date: August 1971
Creator: Lin, Chen-hsiung
Partner: UNT Libraries

Studies on Malic Enzyme from Hymenolepis Diminuta

Description: Malic enzyme from the rat tapeworm, Hymenolepis diminuta, has been purified 320-fold to a final specific activity of 29.4. The purification procedure included heat treatment, followed by column chromatography with Sephadex G-20, two phosphocellulose columns, and Sephadex G-200, respectively. The final purified enzyme appeared to be homogeneous on disc gel electrophoresis and G-200 gel filtration.
Date: December 1971
Creator: Li, Tung
Partner: UNT Libraries

Effects of High Altitude Exposure on Capillary Permeability

Description: Observations of decreases in plasma volume, shifts in plasma and lymph protein concentrations, and increases in capillary permeability at high altitude have been reported in the literature by several investigators. This investigation was begun in an attempt to elucidate the possible significance of these phenomena in future space exploration, and because of the lack of knowledge concerning the underlying mechanisms. The purpose of this investigation was to determine the effects of exposure to hypobaric pressures on the capillary permeability to the normal plasma and lymph proteins.
Date: December 1971
Creator: Reaves, Troy Albert
Partner: UNT Libraries

Lactate Dehydrogenase of Hymenolepis Diminuta: Isolation and Characterization

Description: Lactate dehydrogenase was isolated in pure form from crude extract of the cestode Hymenoleois diminuta by heat treatment and column chromatography. The purified enzyme has a specific activity of 106 units per mg protein. The molecular weight of the purified protein was 75,000 as determined by Sephadex gel filtration and analytical ultracentrifugation. An equilibrium ultracentrifugation study suggests a subunit molecular weight of 39,000. From these data, a dimer form of the native enzyme is proposed.
Date: December 1971
Creator: Burke, William F.
Partner: UNT Libraries

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
Partner: UNT Libraries

The Biological Elimination of Phenols in the Effluent of a Wood Preserving Plant

Description: The removal of phenols from the waste waters of wood preserving plants has always presented problems. The purpose of this paper is to investigate the possibility of employing a biological system to reduce the phenol content of effluent from these plants.
Date: August 1971
Creator: Rainey, John G.
Partner: UNT Libraries

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 the accumulation of the insecticide by G. barbipes under static exposure; and (4) to quantify the uptake and loss of carbaryl by G. barbipes under daily-renewed sublethal dosages.
Date: December 1971
Creator: Gash, Stephen L.
Partner: UNT Libraries

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
Partner: UNT Libraries

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 reversible. Ouabain inhibition was partially reversible by soaking the nerve in aerated Ringer's. Application of 120 kv x-rays (75 Kr at 4.9 Kr/min) to nerves during the linear decline in spike amplitude brought about a marked enhancement (146%) of inhibition by 99% CO/l% 02, nitrogen (136%), and ouabain (265%). All bhanges were shown to be statistically significant by a regression analysis. However, x-irradiation did not appear to alter the air reversibility of carbon monoxide and nitrogen inhibitions nor the reversibility in Ringerts of the ouabain inhibition. Additionally x-irradiation completely blocked light reversal of 98% CO/2% 02 inhibition and produced a decline in activity. A possible interpretation of these results is a compensation for radiation action at this dosage requiring metabolism and ion pump activity.
Date: December 1971
Creator: Thompson, Wesley J.
Partner: UNT Libraries

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.
Partner: UNT Libraries