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  Partner: UNT Libraries
 Degree Discipline: Biology
 Degree Level: Master's
 Collection: UNT Theses and Dissertations
Comparative Ultrastructural Study between Young and Adult forms of Trypanosoma Lewisi

Comparative Ultrastructural Study between Young and Adult forms of Trypanosoma Lewisi

Date: August 1973
Creator: Abdul-Salam, Jasem M.
Description: The purpose of this study was to examine the ultrastructure of both young (dividing form) and adult (stationary form) of Trypanosoma lewisi. Changes observed between the two forms of the organism were related directly to data obtained from previous comparative biochemical studies conducted on these forms of Trypanosoma lewisi.
Contributing Partner: UNT Libraries
Ultrastructural Changes of Tumor Implants in Mice

Ultrastructural Changes of Tumor Implants in Mice

Date: January 1970
Creator: Abrams, Joe A.
Description: The purpose of this investigation was to observe the sequential ultrastructural changes in tumor implants of a well established tumor line in isologous mice.
Contributing Partner: UNT Libraries
Diphenyloxazole Metabolism by Aryl Hydrocarbon Hydroxylase

Diphenyloxazole Metabolism by Aryl Hydrocarbon Hydroxylase

Date: December 1976
Creator: Abreu, Mary E.
Description: 2,5-Diphenyloxazole (PPO) was tested as a potential alternate inducer for the aryl hydrocarbon hydroxylase (AHH) system. Its apparent lack. of carcinogenicity and toxicity provide a possible system for investigation of enzyme systems related to chemical carcinogenesis without exposure of the researcher to potent carcinogenic compounds. These studies found PPO to be an inducer of AHH in cultured human lymphocytes. When PPO was utilized as a substrate for the AHH assay system, the major metabolites produced were strongly fluorescent. A simple fluorometric assay was developed which employed PPO as the substrate and which measured constitutive activity more efficiently than similar assays using benzo(a)pyrene as the substrate. Quantitation of both basal and induced lymphocyte AHH metabolism of PPO may be applicable to human population studies and may provide a tool to determine possible genetic variables with respect to carcinogen metabolism related to cancer risk.
Contributing Partner: UNT Libraries
DNA-DNA Hybridization of Methane Oxidizing Bacteria

DNA-DNA Hybridization of Methane Oxidizing Bacteria

Date: December 1976
Creator: Ackerson, Jill W.
Description: Bacteria classified in the family Methylomonadaceae must derive their carbon from one-carbon compounds. They are characterized by the possession of internal membranes of two types. Type I membranes are layered and fill the middle of the cells while type II membranes form concentric layers around the periphery of the cells. Also, there are two metabolic pathways by which the methylobacteria assimilate one-carbon compounds. Further evidence of this dichotomy was sought by DNA-DNA saturation hybridization of DNAs from both types of methylobacteria. Very low DNA-DNA homology was seen between types I and II or within the types. It was not possible, therefore, to correlate the degree of genetic relatedness with either the nature of the internal membranes or the pathway of carbon assimilation.
Contributing Partner: UNT Libraries
A Study of the Bacterial Flora of Food Utensils in Hardin College Cafeteria and Twenty-Five Eating Establishments in Wichita Falls, Texas

A Study of the Bacterial Flora of Food Utensils in Hardin College Cafeteria and Twenty-Five Eating Establishments in Wichita Falls, Texas

Date: 1949
Creator: Adams, Isaac Newton
Description: The problem of this thesis consists primarily of a bacteriological survey of the eating utensils of Hardin College Cafeteria and twenty-five other eating establishments in the city of Wichita Falls, Texas. This investigation was made primarily with reference to a determination of the possible presence of typhoid and related organisms, and secondarily to an investigation of the actual presence of those bacterial organisms associated with the more common outbreaks of food poisoning.
Contributing Partner: UNT Libraries
Solvent Effects and Bioconcentration Patterns of Antimicrobial Compounds in Wetland Plants

Solvent Effects and Bioconcentration Patterns of Antimicrobial Compounds in Wetland Plants

Date: May 2011
Creator: Adhikari, Sajag
Description: This study looked at effects of organic solvents dimethylsulfoxide, dimethylformamide and acetone at 0.01%, 0.05% and 0.1% concentration on germination and seedling development wetland plants. Even at 0.01% level, all solvents affected some aspect of seed germination or seedling growth. Acetone at 0.01% was least toxic. Root morphological characteristics were most sensitive compared to shoot morphological characteristics. This study also looked at bioconcentration patterns of antimicrobial compounds triclosan, triclocarban and methyl-triclosan in wetland plants exposed to Denton Municipal Waste Water Treatment Plant effluent. Bioconcentration patterns of antimicrobial compounds varied among species within groups as well as within organs of species. The highest triclocarban, triclosan and methyltriclosan concentration were in shoot of N. guadalupensis, root of N. lutea and in shoots of P. nodous respectively.
Contributing Partner: UNT Libraries
Some Effects of X-Irradiaion on the Adrenal Response to Hypothalamic Stimulation in Rats

Some Effects of X-Irradiaion on the Adrenal Response to Hypothalamic Stimulation in Rats

Date: January 1967
Creator: Agnew, Robert Laing
Description: Exactly where in the hypothalamus is the adrenal-pituitary response to X-irradiation "triggered" or initiated? Moreover, does ionizing radiation act directly on specific centers in the brain or does it act indirectly via the production of some humoral agents? Finally, what role does the hypothalamus play in the radiation-syndrome? The purpose of the present study was to attempt to answer these questions by determining the effects of two stressor agents, X-irradiation and electrical stimulation applied either singly or together, on the activity of the adrenal-pituitary axis. The parameters measured were changes in plasma corticosterone, in circulating eosinopihils, and in adrenal gland weight.
Contributing Partner: UNT Libraries
Effects of X-irradiation on Ion Flux in Desheathed Toad Sciatic Nerves

Effects of X-irradiation on Ion Flux in Desheathed Toad Sciatic Nerves

Date: January 1969
Creator: Albin, Leslie O.
Description: The purpose of this thesis is to determine the effects of x-irradiation on the efflux of potassium, sodium and calcium ions from stimulated and unstimulated desheathed sciatic nerves.
Contributing Partner: UNT Libraries
Food Habits and Dietary Overlap of Four Species of Rodents from the Mesquite Plains of Texas

Food Habits and Dietary Overlap of Four Species of Rodents from the Mesquite Plains of Texas

Date: May 1972
Creator: Alcoze, Thomas M.
Description: The coexistence of Dipodomys ordii and Perognathus hispidus with Peromyscus maniculatus and Reithrodontomys montanus was studied in a grassland association of central Texas. The food habits of these species were compared with information from habitat vegetation analysis in an effort to determine food selectivity and the amount and importance of niche overlap and competition among these rodents.
Contributing Partner: UNT Libraries
Pressure-Flow Relationships in the Isolated Cerebral Circulation of the Dog

Pressure-Flow Relationships in the Isolated Cerebral Circulation of the Dog

Date: June 1962
Creator: Alexander, William Carter
Description: The purpose of this investigation is to determine the pressure-flow relationships in the isolated canine cerebral vascular bed. These relationships in vessels which supply an organ surrounded by bone are theoretically influenced by limiting factors which are not present in those vessels surrounded by soft tissue. An evaluation of the extent of these limitations is essential to thorough understanding of the dynamics of the cerebral vascular bed.
Contributing Partner: UNT Libraries
Isolation, Purification, and Characterization of Aldolase from Human Heart

Isolation, Purification, and Characterization of Aldolase from Human Heart

Date: August 1972
Creator: Allen, Benja L.
Description: Aldolase from human heart has been purified 128-fold to a final specific activity of 11.52 units per mg. The purification procedure employed column chromatography on phosphocellulose.
Contributing Partner: UNT Libraries
Microbiotic Cycles in Lake Hefner

Microbiotic Cycles in Lake Hefner

Date: January 1966
Creator: Allison, Richard C.
Description: The purposes of this paper are 1) to determine the microbiotic cycles which occur in Lake Hefner in order to form a basis for ascertaining the effects of future additions of evaporation control chemicals on the biological life of this reservoir, and 2) to make a generalization as to the microbiotic cycles which might occur in Southwestern reservoirs.
Contributing Partner: UNT Libraries
Retinoic acid Treatment Affects Kidney Development and Osmoregulatory System in the Developing Chicken (Gallus Gallus)

Retinoic acid Treatment Affects Kidney Development and Osmoregulatory System in the Developing Chicken (Gallus Gallus)

Date: May 2011
Creator: Alvine, Travis Douglas
Description: Development is a dynamic process characterized by critical periods in which organ systems are sensitive to changes in the surrounding environment. In the current study, critical windows of embryonic growth and kidney development were assessed in the embryonic chicken. All‐trans retinoic acid (tRA) influences not only organogenesis and cell proliferation, but also targets metanephric kidney nephrogenesis. Embryonic chickens were given a single injection of tRA on embryonic day 8. tRA decreased embryo, kidney, and heart mass from day 16 to day 18. However, mass specific kidney and heart masses showed no differences. Whole blood, plasma, and allantoic fluid osmolality were altered in tRA treated embryos from day 16 to day 18. In addition, hematocrit, red blood cell count, and hemoglobin concentration were altered in tRA treated embryos. The results suggest that although nephrogenesis was not affected by tRA, the developing osmoregulatory system was altered in tRA treated embryos.
Contributing Partner: UNT Libraries
Callibaetis Floridanus (Ephemeroptera: Baetidae) Life History and Production in a West Texas Playa

Callibaetis Floridanus (Ephemeroptera: Baetidae) Life History and Production in a West Texas Playa

Date: May 1998
Creator: Anderson, Gregory (Gregory Mark)
Description: A life history study of Callibaetis floridanus was conducted over the wet cycle of a playa on the Southern High Plains of Texas from June through September 1995.
Contributing Partner: UNT Libraries
A Comparative Study of Four Genealogies to Determine Predisposition to Cancer

A Comparative Study of Four Genealogies to Determine Predisposition to Cancer

Date: 1941
Creator: Andrew, Vivian Wilson
Description: This study was made in an effort first, to determine the mode of transmission of the inheritance of a predisposition to cancer as revealed through the analyses of four separate human genealogies, and second, to make a comparative study of the genealogies to determine whether the mode of transmission is the same.
Contributing Partner: UNT Libraries
Evaluation of virulence in wild type and pyrimidine auxotrophs of  Pseudomonas aeruginosa using the eukaryotic model system  Caenorhabditis elegans.

Evaluation of virulence in wild type and pyrimidine auxotrophs of Pseudomonas aeruginosa using the eukaryotic model system Caenorhabditis elegans.

Access: Use of this item is restricted to the UNT Community.
Date: August 2004
Creator: Anvari, Sara
Description: The human opportunistic pathogen, Pseudomonas aeruginosa PAO1, has been shown to kill the nematode Caenorhabditis elegans. C. elegans has been a valuable model for the study of bacterial pathogenesis, and has reinforced the notion that common virulence and host defense mechanisms exist. Recently, the pyrimidine pathway was shown to regulate virulence levels. Therefore, mutations in the pyrimidine pathway of PAO1 showed decrease virulence in the nematode. When starving the nematode, bacterial resistance was also shown to increase. It was hypothesized that starvation induced the DAF pathway, which regulates the transcription of genes involved with the antibacterial defense mechanism. Further research will be conducted to test this theory by performing RNAi experiments for the genes functioning in the antibacterial defense mechanism.
Contributing Partner: UNT Libraries
Inquiry-based science for high school students: a forensic unit

Inquiry-based science for high school students: a forensic unit

Access: Use of this item is restricted to the UNT Community.
Date: August 2000
Creator: Apple, Kendra Kea
Description: This project constitutes an instructional unit for honors biology that involves the use of science in the field of criminal investigation and forensics. Before beginning the unit, the learners should have mastered basic laboratory skills, including use of the microscope. They should also have an understanding of the basic structure and function of DNA and its role in heredity and protein synthesis. The standard time frame is 24 days with 70-minute periods, but can be easily adjusted to meet classroom needs. Several instructional strategies enhance student learning and make science fun. The unit is inquiry-driven and activity-based. Students are surprised by the crime, gather and analyze evidence, and work towards proposing an explanation. This real world problem involves the use of cooperative learning and a variety of assessment techniques.
Contributing Partner: UNT Libraries
Effector Response of the Aspartate Transcarbamoylase From Wild Type  Pseudomonas Putida and a Mutant with 11 Amino Acids Deleted at the N-terminus of PyrB.

Effector Response of the Aspartate Transcarbamoylase From Wild Type Pseudomonas Putida and a Mutant with 11 Amino Acids Deleted at the N-terminus of PyrB.

Date: May 2002
Creator: AsFour, Hani
Description: Like its enteric counterpart, aspartate transcarbamoylase (ATCase) from Pseudomonas putida is a dodecamer of two different polypeptides. Unlike the enterics, the Pseudomonas ATCase lacks regulatory polypeptides but employs instead inactive dihydroorotases for an active dodecamer. Previous work showed that PyrB contains not only the active site but also the effector binding sites for ATP, UTP and CTP at its N-terminus. In this work, 11 amino acids were deleted from the N-terminus of PyrB and the ATCase with the truncated protein was expressed in E. coli pyrB- and purified. The wild type enzyme was similarly treated. Velocity-substrate plots without effectors gave Michaelis-Menten kinetics in all cases. Deleting 11 amino acids did not affect dodecameric assembly but altered effector responses. When carbamoylphosphate was varied, the mutant enzyme was inhibited by UTP while the wild type enzyme was activated 2-fold. When the aspartate was varied, CTP had no effect on the mutant enzyme but strongly inhibited the wild type enzyme.
Contributing Partner: UNT Libraries
Evaluation of a Constructed Wetland to Reduce Toxicity from Diazinon at the Pecan Creek Wastewater Treatment Plant, Denton, TX

Evaluation of a Constructed Wetland to Reduce Toxicity from Diazinon at the Pecan Creek Wastewater Treatment Plant, Denton, TX

Date: May 1996
Creator: Baerenklau, Amy L. (Amy Lyn)
Description: The City of Denton Pecan Creek Wastewater Treatment Facility has periodically failed effluent toxicity testing. A Toxicity Identification Evaluation has determined that Diazinon in the effluent is contributing to the observed toxicity. Chlorpyrifos is also implicated as a factor. The City of Denton constructed a half acre experimental wetland to remove Diazinon related toxicity. Results from spiking and microcosm experiments indicate that the wetland can reduce the Diazinon.
Contributing Partner: UNT Libraries
The Isolation, Cultivation and Testing of Organisms Anatagonistic to a Streptomycin Resistant Strain of Pseudomonas Aeruginosa

The Isolation, Cultivation and Testing of Organisms Anatagonistic to a Streptomycin Resistant Strain of Pseudomonas Aeruginosa

Date: 1951
Creator: Banister, Jack Warren
Description: The problem of finding an efficient antibiotic against Pseudomonas aeruginosa which can be used in the clinical treatment of genito-urinary tract infections resistant to treatment by streptomycin has not yet been solved. Therefore, this problem has consisted of first, the acquisition of possible inhibitors of the streptomycin resistant strain of Pseudomonas aeruginosa; second, the selection and identification of those which show a marked antagonism toward this organism; third, the determination of the antibiotic spectra of the inhibitors; fourth, the determination of whether the streptomycin resistant strain could also acquire a resistance to the antibiotic produced by its inhibitors; and last, an attempt to evaluate the therapeutic possibilities of the antibiotics demonstrated.
Contributing Partner: UNT Libraries
The Use of Similarity Indicies to Assess the Spatial Differences of the Phytoplankton Communities in Lake Ray Roberts, Texas

The Use of Similarity Indicies to Assess the Spatial Differences of the Phytoplankton Communities in Lake Ray Roberts, Texas

Date: August 1996
Creator: Banks, Kenneth E. (Kenneth Edward)
Description: A study of the phytoplankton communities of Lake Ray Roberts was conducted at three sampling sites on two sampling dates during the summer of 1995, assessing both community structure and chlorophyll a concentrations. Eight similarity indices were then used to characterize and compare the communities of these sites. Both community similarity and chlorophyll a concentrations were evaluated using a minimum detectable difference equation to determine the amount of change that must occur in these parameters in order to be deemed statistically significant. The Bray-Curtis Index was shown to be the most adequate index evaluated, and was subsequently used in conjunction with bootstrap analysis to determine the similarity between the three sampling sites.
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A Comparative Study of Egg Media in the Primary Isolation of Mycobacterium Tuberculosis

A Comparative Study of Egg Media in the Primary Isolation of Mycobacterium Tuberculosis

Date: 1949
Creator: Barberousse, Loris J.
Description: The primary purpose of this investigation is not only to improve the present technique of culture of Mycobacterium tuberculosis, but also to make a comparative study of the media use, namely, Veterans Administration modification of Trudeau's medium, Lowenstein's egg medium, and that developed by the author, in order to find which, if any, of these will most easily and effectively meet the needs of the hospital laboratory.
Contributing Partner: UNT Libraries
Bacterial Survey of Representative Wells of Canyon, Texas, with Special Emphasis on Sanitation

Bacterial Survey of Representative Wells of Canyon, Texas, with Special Emphasis on Sanitation

Date: 1944
Creator: Barnes, Adele
Description: The problem of this thesis consists of a bacterial analysis of twenty-five representative wells within a radius of thirty miles of Canyon, Texas. An attempt has been made to determine the possible presence of the typhoid organism in these wells.
Contributing Partner: UNT Libraries
The Effect of Geosmin on the Growth of Bacillus cereus

The Effect of Geosmin on the Growth of Bacillus cereus

Date: August 1972
Creator: Barnes, Randall D.
Description: The purpose of this study was to determine the effect of varying concentrations of geosmin on the growth of Bacillus cereus.
Contributing Partner: UNT Libraries
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