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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

An Ecological Survey of the Herpetofauna of Palo Pinto County, Texas

Description: The purpose of this research was to compile a presence list of reptiles and amphibians that occur in Palo Pinto County, Texas, and to investigate the ecological distributions and zoogeographic affinities of these herpetiles. The study area was chosen primarily because of its location in North Central Texas and its rugged topography, which sets it apart from the surrounding area.
Date: August 1969
Creator: Porter, Stuart T.
Partner: UNT Libraries

An Ecological Survey of the Reptiles and Amphibians of Wise county, Texas

Description: The purpose of this study was to record the relationships between the reptiles and amphibians of Wise County and the ecological subdivisions of the area. Wise County was chosen because of the heterogenity of the area and because of its proximity to other counties which have been previously and similarly studied.
Date: January 1970
Creator: Welch, Donald A.
Partner: UNT Libraries

The Effect of Carbon Monoxide on the Growth of an Aquatic Streptomycete

Description: The major purpose of this investigation was to determine the effect of carbon monoxide on the development of various morphological phases of a single isolate of the aquatic streptomycetes and to elucidate the physiological differences between terminal respiration in the primary and secondary stages. A secondary purpose was to repeat the work of Michael Lee Higgins involving the effect of anaerobiosis on the growth of the organism.
Date: August 1966
Creator: Francisco, Donald Edward
Partner: UNT Libraries

Effect of Colchicine on Neuronal Excitabilty

Description: The abundance of microtubules in receptive dendrites suggests they may function in sensory transduction. Responses of frog muscle spindle receptors and joint receptors is inhibited within 25 minutes by 50 mM colchicine, a microtubuledisrupting agent. The inhibition is reversible upon removal of colchicine, and the time course of recovery is comparable to that of inhibition. Frog olfactory responses are briefly inhibited by washing the olfactory mucosa with perfusion fluid. Colchicine accentuates the inhibition and substantially retards the rate of recovery in a dose-dependent fashion. Colchicine does not affect axonal conduction, nor the oxygen uptake of isolated crab or frog leg nerves. The inhibitory action of colchicine is therefore an effect on the electrical excitability of the receptive dendrites or soma, and not an effect on axonal conduction.
Date: August 1978
Creator: Okafo, Ngozi
Partner: UNT Libraries

Effect of Light and Other Environmental Factors on Growth and Carotenogenesis of Corynebacterium Species Strain 7E1C

Description: This investigation studies effects of environmental factors on growth and carotenogenesis in Corynebacterium strain 7ElC. Changes in pH were found to effect growth more than carotenogenesis. However, certain nutrients or long incubation periods stimulated carotenoid formation more than growth. Dark conditions in a mineral salts-glucose medium stimulated growth, but minimized carotenogenesis. Tryptic soy broth or yeast extract elicited carotenogenesis in darkness. Although brief light exposure during inoculation was photoinductive, continuous exposure to light following inoculation was required for maximum pigment synthesis. Dark grown stationary phase cells required 24-hours of light for maximum pigment synthesis. Chloramphenicol inhibition of carotenogenesis in dark grown cells exposed to light showed that enzymes needed for carotenoid synthesis were absent from dark grown cultures.
Date: August 1974
Creator: Howard, Marta E.
Partner: UNT Libraries

The Effect of Light on Carotenoid Synthesis in Corynebacterium 7E1C

Description: The effects of light, light "mimicking" chemicals, and protein synthesis inhibitors on the photo-induced carotenogenesis of Corynebacterium 7EIC were studied. Changes in the dosage of fluorescent light applied to dark grown cells showed a dose related carotenogenic response. Maintaining the same dosage but varying the wavelength of monochromatic light revealed that light with a wavelength of 280 to 450nm was responsible for photo-induction. It further showed a peak of photo-induction between the wavelengths of 370 and 430nm. The light "mimicking" chemicals antimycin A and p-Chloromercurybenzoate were shown to have no light "mimicking" effects. The transcriptional inhibitor of protein synthesis actinomycin D partially inhibited, and chloramphenicol a translational inhibitor, completely inhibited photo-induced carotenogenesis.
Date: May 1977
Creator: Endicott, George R.
Partner: UNT Libraries

The Effect of Media Constituents on Growth and Pigment Production of Mycobacterium Phlei, Pseudomonas Fluorescens, Pseudomonas Aeruginosa, and Staphylococcus Citreus

Description: Little is known concerning the production and significance of bacterial pigments. There is seemingly an open field for studying the effects produced by varying the nutritive content of culture media upon which organisms are grown. This has led to an especial interest in, and the purpose of this investigation.
Date: 1947
Creator: Robbins, Finis E.
Partner: UNT Libraries

The Effect of Repeated Antigen Injections on the C' and C'4 Titers in Guinea Pig Serum

Description: In this study the effects of repeated antigen injections on total complement (C') and C'4 of guinea pig serum were investigated to determine if constant antigenic stimulation would show changes in the C' and C'4 titers. Attempts were also made to correlate any changes with variations in antibody titers during the repeated antigen injections.
Date: June 1961
Creator: Teague, Perry Owen
Partner: UNT Libraries

The Effect of Sodium Salicylate on the Ultrastructure of Trypanosoma lewisi

Description: This study examines ultrastructural changes occurring in seven- and fourteen-day populations of Trypanosorfa lewisi when 60 mg sodium salicylate is administered to the host. These changes were related to the host-immune response. Seven-day trypanosomes showed approximately 10 posterior volutin granules. Seven-day trypanosomes whose host had received salicylate exhibited. 30 to 40 volutin granules, and their posterior tip exhibited volutin granules in high numbers sometimes excluding other cellular elements. Fourteen-day trypanosones showed fewer volutin granules than seven-day, salicylate-treated ones. Salicylate treatment caused no additional ultrastructural alterations. Thus the volutin granules are not linked to the reproduction inhibiting antibody (ablast in) but may be involved in the formation of the trypanocidal antibodies.
Date: August 1974
Creator: Beck, Charles F.
Partner: UNT Libraries

The Effects of 3-Deazaguanine on Chick Embryo Fibroblasts and Rat Kidney Cells Infected with Temperature-Sensitive Mutant and Wild-Type Rous Sarcoma Viruses

Description: Chick embryo fibroblasts and rat kidney cells infected in vitro with Rous Sarcoma viruses were treated with 3-deazaguanine (3-DG). The findings revealed that 3-DG inhibited virus-induced cellular transformation. Degree of inhibition is dependent on concentration and frequency of media change. 3-DG at the concentrations tested will not reverse transformed cells to the untransformed state and does not have marked effect on replication of viruses. Upon removal of 3-DG, its effect was shown to be reversible. Cell growth was generally retarded in medium containing 3-DG. When xanthosine and inosine were added to the medium, cell growth was unaffected, but it increased in guanosine.
Date: December 1979
Creator: Fadare, Samuel O.
Partner: UNT Libraries

Effects of Altitude on Pressure-Flow Relationships in the Vascular Bed of the Hind Limb of the Dog

Description: The purpose of this investigation was to study the effects of decreasing barometric pressure upon the pressure-flow relationships in a peripheral vascular bed in an attempt at better delineation of the autoregulatory mechanisms. A decrease in barometric pressure does influence the transmural pressure and could theoretically affect smooth muscle tone. An evaluation of the extent of the transmural effect is essential to understanding vascular dynamics at altitudes.
Date: August 1966
Creator: Roberts, Donald E.
Partner: UNT Libraries

Effects of Antigen Injection on Titer of C'3 and C'4 Complement Components of Rat Serum

Description: This work attempts to establish some phenomenon of a rise in titer of C'3 and C'4 due to antigenic stimulation. Normal level of complement is established and compared to other workers as well as against guinea pig levels. Young rats were bled to establish normal levels of complement. The animals were then injected with an antigenic substance and after a period of seven days were bled again to determine the level of complement. Various antigenic and non-antigenic substances were used as well as normal saline injections for control.
Date: August 1957
Creator: Whalen, Paul Lorrance
Partner: UNT Libraries

The Effects of Common Electrolytes on Growth and Development of Selected Species of Aquatic Actinomycetes

Description: The role that aquatic actinomycetes play, in the production of tastes and odors in water supplies has been investigated since 1948. The ability of these organisms to produce by-products in lakes and streams, which renders the water unpalatable, is of considerable public health importance. It is desirable that the waterworks industry has as much information as possible concerning the factors that contribute to the growth of these organisms. Since it appears that the aquatic actinomycetes may be isolated from most fresh-water sources, the problem of diversified environments and nutritional requirements offers an excellent field of investigation. The fresh-waters of the world contain variable quantities of electrolytes that may determine in part the biological activity of these organisms. The unsolved questions in this instance are concerned with the electrolytes present and their quantitative effects on the growth and development of these forms.
Date: August 1959
Creator: Sissom, Stanley L.
Partner: UNT Libraries