Factors Involved in Passive Transfer of Contact Hypersensitivity (open access)

Factors Involved in Passive Transfer of Contact Hypersensitivity

Delayed hypersensitivity can be conferred passively to normal animals. There exists a period when whole peritoneal exudate cells will passively confer delayed sensitivity, but a sonic extract from them will not; however, after a few more days, both whole cells and sonic extracts could transfer sensitivity. This investigation was undertaken to study the differences in cells collected at two different time intervals after initial sensitization of guinea pigs with 1-fluoro-2,4-dinitrobenzene.
Date: August 1966
Creator: Ellis, Walter L.
System: The UNT Digital Library
Presence of Krebs Cycle Intermediates in Primary Mycelia of an Actinomycete (open access)

Presence of Krebs Cycle Intermediates in Primary Mycelia of an Actinomycete

The purpose of this study is to determine the presence or absence of a typical Krebs cycle metabolism in the primary mycelia of an aquatic streptomycete.
Date: August 1968
Creator: Callaway, Joe Raymon
System: The UNT Digital Library
The Effect of Carbon Monoxide on the Growth of an Aquatic Streptomycete (open access)

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

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
System: The UNT Digital Library
Studies of Mouse Hypersensitivities (open access)

Studies of Mouse Hypersensitivities

Having considered the data collected thus far concerning immediate and delayed hypersensitivity reactions in the mouse, the experimentation following is devised essentially to follow the pattern of Crowle in the production and testing for immunoresponse. Instead of using the normal solvent, that is, acetone, this work is also intended to partially evaluated the use of dimethyl sulfoxide as a solvent for the contact allergin, dinitroflurobenzene.
Date: August 1966
Creator: Meador, Earl C.
System: The UNT Digital Library
Laboratory and field studies of cadmium effects on  Hyalella azteca in effluent dominated systems. (open access)

Laboratory and field studies of cadmium effects on Hyalella azteca in effluent dominated systems.

Laboratory single-species toxicity tests are used to assess the effects of contaminants on aquatic biota. Questions remain as to how accurately these controlled toxicity tests predict sitespecific bioavailability and effects of metals. Concurrent 42-day Hyalella azteca exposures were performed with cadmium and final treated municipal effluent in the laboratory and at the University of North Texas Stream Research Facility. Further laboratory testing in reconstituted hard water was also conducted. Endpoints evaluated include survival, growth, reproduction, and Cd body burden. My results demonstrate that laboratory toxicity tests may overestimate toxicity responses to cadmium when compared to effluent dominated stream exposures. Discrepancies between endpoints in the three tests likely resulted from increased food sources and decreased cadmium bioavailability in stream mesocosms
Date: August 2003
Creator: Stanley, Jacob K.
System: The UNT Digital Library
Heat Resistance in Vegetative Cells and Cysts of Azotobacter (open access)

Heat Resistance in Vegetative Cells and Cysts of Azotobacter

The purpose of the current study is to determine something of the nature of the heat resistance in Azotobacter, if in fact this is found to exist. An attempt is made to determine the specific physiological state associated with heat resistance as well as to resolve this resistance quantitatively.
Date: August 1969
Creator: Rosenthal, Raoul S.
System: The UNT Digital Library
Metabolism of Hydrocortisone by X-Irradiated Rat Liver Tissue as Determined by the Porter-Silber Chromagen Method (open access)

Metabolism of Hydrocortisone by X-Irradiated Rat Liver Tissue as Determined by the Porter-Silber Chromagen Method

The present study may be considered endocrinological and radiobiological in nature. The endocrinology phase was concerned with studying the changes in endocrine function following the application of a stress agent. X-irradiation was chosen as the stressor in order to determine any difference in effect of this stressor from others which have been studied, e. g. heat, cold, metabolic poisons. Liver slices taken from rats at various time intervals following whole body X-irradiation were tested for their ability to metabolize hydrocortisone from a Krebs-Ringer solution.
Date: August 1959
Creator: Pryor, Nan Webb
System: The UNT Digital Library
Studies on the Nutrition of Rhodospirillum Rubrum (open access)

Studies on the Nutrition of Rhodospirillum Rubrum

The purpose of this study has been to examine the nutritional requirements of Rhodospirillum rubrum and, on the basis of the results, develop a culture medium which could be use to promote more rapid and abundant growth facilitating the laboratory cultivation and observations of the properties so exhibited.
Date: August 1957
Creator: Wentworth, Margaret Earl
System: The UNT Digital Library
X-irradiation and Drug Effects on Ventral Root Potentials in Cat Spinal Cords (open access)

X-irradiation and Drug Effects on Ventral Root Potentials in Cat Spinal Cords

The purpose of the present study was sixfold: 1. To study the effects of x-irradiation on spinal cord activity. 2. To study the effects of CNS drugs on spinal cord function as reflected by changes in the ventral root potentials. 3. To ascertain whether one can alter the observed spinal response to ionizing radiation by applying CNS drugs prior to, during, and following x-irradiation of a given spinal cord segment. 4. To shed some light on the role of higher brain centers on spinal reflexes. 5. To shed some light on the loci of radiation insult to the spinal cord. 6. To establish evidence for a possible drug-irradiation interaction in mammals.
Date: August 1964
Creator: Crow, Robert V.
System: The UNT Digital Library
Photoreactivation Studies on Azotobacter vinelandii ATCC 12837 (open access)

Photoreactivation Studies on Azotobacter vinelandii ATCC 12837

This thesis was written to study photoreactivation in different physiological conditions of the vegetative cell as well as the photoreactivation of the two morphological states of the Azotobacter cell: the vegetative cell and the cyst.
Date: August 1968
Creator: Peterson, Johnny Wayne
System: The UNT Digital Library
Effects of X-irradiation on Potassium Flux in Isolated Nerves (open access)

Effects of X-irradiation on Potassium Flux in Isolated Nerves

The purpose of this study, therefore, was threefold in nature: (1) to determine the effects of x-irradiation on the influx and efflux of potassium in compound nerve fibers (2) to attempt to relate the radiation-induced changes in electrical activity with potassium flux and (3) to use the information obtained to gain insight into the possible cellular site (s) of radiation insult to compound nerves.
Date: August 1966
Creator: Ramsey, Christian Norman
System: The UNT Digital Library
Thyroid Ultrastructural Changes Induced by Hypothermia (open access)

Thyroid Ultrastructural Changes Induced by Hypothermia

Investigations have shown that the hypothalamus and pituitary respond to decreases in body temperature by stimulating the thyroid gland to release T3 and T4 hormones. This study was designed to investigate ultrastructural changes of the thyroid gland induced by hypothermia. The ultrastructural changes produces by stimulation by Thyroid Stimulating Hormone were also examined as an adjunct to the hypothermic stimulation of the gland. There was a significant increase in microvilli on the luminal border of follicle cells along with a remarkable increase in numbers of dense granules. The dense granules also demonstrated a polarity being found near the border of the colloid lumen. The glandular changes induced by Thyroid Stimulating Hormone were very similar to those of hypothermia.
Date: August 1979
Creator: Kent, James Simpson
System: The UNT Digital Library
Teratogenesis in Inbred Strains of Mice (open access)

Teratogenesis in Inbred Strains of Mice

The purpose of this investigation is to determine if differences exist between four inbred strains of mice in susceptibility to the drug thalidomide.
Date: August 1966
Creator: Morgan, Robert A.
System: The UNT Digital Library
Anaerobic Organisms in Acute and Chronic Pulmonary Diseases (open access)

Anaerobic Organisms in Acute and Chronic Pulmonary Diseases

This study concerns a determination as to whether anaerobic organisms are involved in pulmonary diseases, particularly those of the chronic type.
Date: August 1958
Creator: Riddel, George Hugh
System: The UNT Digital Library
The Effect of Sodium Salicylate on the Ultrastructure of Trypanosoma lewisi (open access)

The Effect of Sodium Salicylate on the Ultrastructure of Trypanosoma lewisi

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.
System: The UNT Digital Library
Adenylate Energy Charge Determinations of Soil Bacteria Grown in Soil Extract Medium (open access)

Adenylate Energy Charge Determinations of Soil Bacteria Grown in Soil Extract Medium

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 those reported for bacteria grown in enriched media. The remainder of the isolates demonstrated low energy charge values, and scant growth in the soil medium.
Date: August 1988
Creator: Rodriguez, Luis A. (Luis Antonio)
System: The UNT Digital Library
Opthalmic Use Of Sodium Cephalothin: An In Vivo Comparison (open access)

Opthalmic Use Of Sodium Cephalothin: An In Vivo Comparison

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 against S. aureus, and against S. pneumoniae, the caphalothin formulations were more effective than gentamicin.In a related stability study, the cephalothin potency of the silicon formulation was maintained for 16 weeks at 4, 25, and 450 C These studies suggest that sodium cephalothin can be formulated as an effective and stable ophthalmic dosage form.
Date: August 1979
Creator: Carney, Gerald R.
System: The UNT Digital Library
Assimilation of Inorganic Nitrogen by Aquatic Actinomycetes (open access)

Assimilation of Inorganic Nitrogen by Aquatic Actinomycetes

It was the purpose of this investigation to present laboratory data concerning the assimilation of inorganic nitrogen by the aquatic actinomycetes. The strains of aquatic actinomycetes under consideration represented a cross section of those currently under culture at North Texas State University.
Date: August 1962
Creator: Davis, Ernst M.
System: The UNT Digital Library
Some Effects of X-irradiation on the Plasma Corticosterone, Adrenal Weights, and Differential Leukocyte Count in the Rat (open access)

Some Effects of X-irradiation on the Plasma Corticosterone, Adrenal Weights, and Differential Leukocyte Count in the Rat

The purpose of the present study was twofold: (1) to determine if X-irradiation can be considered a direct stress agent, and if so, to what extent it differs from other stressors; and (2) to further elucidate the role of the adrenal cortex in the radiation syndrome by determining the more immediate responses of this system to X-irradiation.
Date: August 1962
Creator: Gaugl, John F.
System: The UNT Digital Library
A Multiphasic Study of the Interaction Between the Branchiobdellid Cambarincola Vitrea and its Crayfish Host Procambarus Simulans (open access)

A Multiphasic Study of the Interaction Between the Branchiobdellid Cambarincola Vitrea and its Crayfish Host Procambarus Simulans

The host-parasite interface between the branchiobdellid Cambarincola vitrea Ellis and its crayfish host is investigated along ecological, ultrastructural, serological, and endocrinological lines of evidence. Monthly analysis of a natural branchiobdellid from a vernal habitat demonstrates the annelid to be particularly sensitive to changes involving both the physical habitat as well as the host crayfish.
Date: August 1973
Creator: Koepp, Stephen John
System: The UNT Digital Library
Relationship of Certain Fungi to Azotobacter in Nitrogen-Free Media (open access)

Relationship of Certain Fungi to Azotobacter in Nitrogen-Free Media

Azotobacter and various fungi were grown together in nitrogen-free media. Maximal fungal growth in the medium used was possible only at the expense of Azotobacter cells and growth was always accompanied by acid production. When the medium reached a pH of 2, the bacterial cells were aggregated on fungal hyphae and the culture fluid appeared to be free of Azotobacter. Aspergillus niger grew well at the expense of viable bacteria and other fungi grew well on heat-killed cells of A. vinelandii. Members of the genus Hormodendrum, although not causing significant decrease in pH, were also able to clear turbid cultures of Azotobacter. However, clearing, which involved the attachment of bacteria to fungal hyphae, was dependent on acid production by the fungi. Bacterial aggregation was followed by hyphal attachment, bacterial inactivation, and finally, bacterial cell lysis.
Date: August 1976
Creator: Ray, Manfred G.
System: The UNT Digital Library
A geospatial tool for assessing potential wildland fire risk in central Texas. (open access)

A geospatial tool for assessing potential wildland fire risk in central Texas.

Wildland fires in the United States are not always confined to wilderness areas. The growth of population centers and housing developments in wilderness areas has blurred the boundaries between rural and urban. This merger of human development and natural landscape is known in the wildland fire community as the wildland urban interface or WUI, and it is within this interface that many wildland fires increasingly occur. As wildland fire intrusions in the WUI increase so too does the need for tools to assess potential impact to valuable assets contained within the interface. This study presents a methodology that combines real-time weather data, a wildland fire behavior model, satellite remote sensing and geospatial data in a geographic information system to assess potential risk to human developments and natural resources within the Austin metropolitan area and surrounding ten counties of central, Texas. The methodology uses readily available digital databases and satellite images within Texas, in combination with an industry standard fire behavior model to assist emergency and natural resource managers assess potential impacts from wildland fire. Results of the study will promote prevention of WUI fire disasters, facilitate watershed and habitat protection, and help direct efforts in post wildland fire mitigation and …
Date: August 2005
Creator: Hunter, Bruce Allan
System: The UNT Digital Library