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Advanced Techniques in Microbial and Molecular Biology: Laboratory Procedures for a Graduate Level Course

Description: Advanced laboratory techniques for Microbial and Molecular Biology at the graduate level are presented in this thesis. The procedures for the laboratory experiments are set forth in detail. This laboratory is conducted as two parts, each by a different professor. Part 1 covers the experiments conducted by Dr G.A.O. Donovan. These experiments include an introduction, staining procedures, biochemical reactions, mutagenesis experiment, essays,. preparation and analysis of plasmid DNA and various o… more
Date: August 1998
Creator: Kumar, Shalini
Partner: UNT Libraries
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Assessment of Changes in Aquatic Macrophyte Occurrence Following Introduction of Triploid Grass Carp in a North Texas Reservoir

Description: The objectives of this project were to measure changes in frequency of occurrence of submerged macrophytes over the first two growing seasons following stocking with triploid grass carp at two fish per acre and to measure differences in macrophyte biomass between areas excluded from herbivory and adjacent control sites after 16 months following establishment of exclosures. The project also seeks to measure concentrations of fluridone following the herbicide treatment, and to compare two methods… more
Date: August 1997
Creator: Bickel, Ken (Kenneth E.)
Partner: UNT Libraries
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Assessment of Radio-Tagged Grass Carp (Ctenopharnygodon idella) Dispersion, Vegetation, and Temperature Preferences in North Lake Reservoir

Description: Twenty-nine (Group One, June 8,1995) grass carp (Ctenopharyngodon idella) and five (Group Two, April 18, 1996) grass carp were radio-tagged to monitor movement patterns and habitat preferences on North Lake, a 335 hectare multi-use reservoir located in Irving, Texas. Overall fish mean Average Daily Movement (ADM) rates were 49.2 meters/day (during Half One, 6/8/95-11/30/95) and 5.3 meters/day (during Half Two, 12/14/95-6/6/96). Aquatic macrophtye distribution data were obtained. Radio-tagged gr… more
Date: August 1996
Creator: Lacewell, Jason (Jason Lawrence)
Partner: UNT Libraries
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Biological and Toxicological Responses Resulting from Dechlorination of a Major Municipal Wastewater Treatment Plant Discharge to the Trinity River

Description: Federal regulations such as the Clean Water Act (P.L. 92-500), and its amendments, direct the Environment Protection Agency (EPA) to implement programs to control the releases of conventional pollutants and toxics into the waterways of the United States. The EPA began requiring treatment plants to conduct toxicity tests (biomonitoring) of their effluent discharges. To control toxicity caused by chlorination of wastewater discharges, the EPA also began requiring some treatment facilities to dech… more
Date: August 1995
Creator: Guinn, Richard J. (Richard Joe)
Partner: UNT Libraries
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Changes in Heterozygosity Through Time in American Standardbred and American Saddlebred Horses (1960-1990)

Description: Observed and expected heterozygosity (H) levels for ten electrophoretic blood marker loci and expected H for seven red blood cell (RBC) anitgen/antibody loci were examined for 20 years in American Standardbred and 30 years in American Saddlebred horses. Standardbreds were classed by gait, Trotter and Pacer, and evaluated separately in most analyses. 4,404 Trotters and 12,271 Pacers were found to have statistically highly significant losses of mean total observed H through time for the ten elect… more
Date: May 1992
Creator: King, Judith A. (Judith Ann), 1955-
Partner: UNT Libraries
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Circulatory and Respiratory Responses to Cycle Ergometry at Different Pedal Rates

Description: The effects of moderate workload exercise at different pedal rates on circulatory and respiratory parameters were studied. Five subjects performed seven discontinuous constant-load cycle ergometer tests of 30 minutes duration at pedal rates of 40, 50, 60, 70, 80, 90 and 100 rpm. Oxygen uptake and carbon dioxide production were determined by standard open circuit spirometry, while heart rate was recorded by electrocardiograph. The CO₂ rebreathing procedure was administered during the exercise bo… more
Date: May 1991
Creator: Hernandez, Raymundo
Partner: UNT Libraries
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Comparative Toxicity Responses in Earthworms Lumbricus Terrestris and Eisenia Foetida to Cadmium Nitrate and Chlordane Using Artificial Soil and Filter Paper Exposures

Description: This research compares LC50 and LD50 of earthworms, Lumbricus terrestris and Eisenia foetida exposed to cadmium nitrate and chlordane using 48-h contact filter paper (FP) and 14-d artificial soil (AS) protocols. Both LC50 and LD50 showed that chlordane was more toxic than cadmium in both species regardless of the exposure. The reference toxicant 2-chloroacetamide using the standardized 48-h FP exposure was used to assess the general response of the earthworm prior to toxicity experiments. A glu… more
Date: August 1992
Creator: Muratti Ortiz, Joseph F.
Partner: UNT Libraries
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A Comparison of Predicted and Actual Trophic Status of Lake Ray Roberts, Texas Based on Chlorophyll A

Description: Two years before impoundment, the trophic status of Lake Ray Roberts was predicted by applying the total phosphorus input into the Organization for Economic Cooperation and Development (OECD) eutrophication model. Predicted mean summer epilimnetic (MSE) chlorophyll a of Elm Fork arm, Isle duBois arm and Main Body were in the eutrophic category of the OECD model. Observed MSE chlorophyll a two years after impoundment of Elm Fork arm, Isle duBois and Main Body had not reached their predicted mean… more
Date: May 1999
Creator: Lytle, Lili Lisa
Partner: UNT Libraries
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Development and Application of an Assessment Protocol for Watershed Based Biomonitoring

Description: With numerous bioassessment methodologies available, a regional protocol needs to be developed to ensure that results are comparable. A regional assessment protocol was developed that includes collecting five benthic macroinvertebrate samples, identifying organisms to genus, and calculating the following metrics: Number of Taxa, Total Number of Individuals, Simpson's Diversity Index, Shannon's Diversity Index, Percent Contribution of Dominant Taxa, Hilsenhoffs Biotic Index, and Percent Contribu… more
Date: May 1998
Creator: Schwartz, Joseph Howard
Partner: UNT Libraries
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Development and Validation of a Ramping Treadmill Protocol for the On-Line Measurement of Four Aerobic Parameters

Description: Previously, Whipp et. al. (J. Appl. Physiol.: Respirat. Environ. Exerc. Physiol. 50(1):217-221, 1981) demonstrated the feasibility of determining four parameters of aerobic function, identified as maximum oxygen uptake (μVO_2), VO_2 at anaerobic threshold (θan), the time constant for oxygen uptake kinetics (rVO_2) and work efficiency (η), using a short duration ramped bicycle ergometer exercise test. Because of the importance of being able to measure these parameters on a variety of measurement… more
Date: May 1990
Creator: Cowell, Lynda L. (Lynda Lea)
Partner: UNT Libraries
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Development of an In Vitro Protoplast Culture System for Albizia Lebek (L.) Benth., an Economically Important Leguminous Tree

Description: An in vitro system of generating protoplasts from their callus cultures was established. The friable callus was more productive in terms of producing protoplasts than the green compact callus. The concentration of the various cell wall degrading enzymes had an effect on the viability of the protoplasts in the medium. The protoplast system developed from the experiments was stable and could be used for the transformation experiments of Albizia lebek and for other plant improvement practices.
Date: August 1998
Creator: Sinha, Debleena
Partner: UNT Libraries
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The Effect of Long-Term Moderate Amounts of Ethanol on Paraventricular Nuclei Activity on Cold Stressed Adult Rats

Description: The effects of moderate, long-term intake of ethanol on the hypothalamic response to cold stress were examined. The long-term experimental animals were given .25 ml of 28% ethanol or .25 ml of water orally once a day, five days a week for fourteen months. A stainless steel electrode was then surgically implanted into the paraventricular nucleus, after which the animal was subjected to cold stress (-150 C, 10 min.). Recordings were taken in the forms of frequency and activity. The data clearly i… more
Date: December 1990
Creator: McKinnon, Mark S. (Mark Steven)
Partner: UNT Libraries
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Effect of pH on the Persistence and Toxicity of Cyfluthrin to Chironomus Tentans

Description: The effect of pH upon the aquatic toxicity of cyfluthrin was determined in 48 h static acute toxicity tests using 2nd instar Chironomus tentans larvae. Tests were conducted in both dechlorinated tap water and lake water of pH 8.0, 7.2, and 6.6. After 48 h, immobilized and dead larvae were removed and replaced with 2nd instar larvae to assess the persistence of toxicity. Midges were cultured in water adjusted to the pH values used in testing. Toxicity if cyfluthrin varied inversely with pH. An i… more
Date: May 1992
Creator: Hambleton, Faith Ann (Faith Ann Elizabeth)
Partner: UNT Libraries
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The Effects of Organic Surface Amendments on Soil Nutrients and Initial Tree Establishment

Description: This study examined the effects of replicating woodland soil surface horizonation on the nutrient status of underlying soils and the initial establishment and growth of trees. A total of 283 container grown trees were planted in a bufferzone around a future landfill site. Control amendments consisted of an 8 cm layer (0.5 m3) of wood chips applied in a circular area of 4.6 m2 around the trees' planting pit. For the treatment, a 2.5 cm layer of composted biosolids (0.15 m3 or 80 Mg/ha) was appli… more
Date: May 1999
Creator: Thuesen, Kevin (Kevin Andrew)
Partner: UNT Libraries
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Estimated Extent and Fate of Chlorinated Solvent Contamination in the Soil of the Naval Air Station, Dallas, Texas

Description: This thesis estimates the spatial extent of chlorinated solvent contamination of the soil at the Naval Air Station, Dallas, then estimates the fate and transport of these contaminants, over time, using the Soil Transport and Fate database and the Vadose-Zone Interactive Processes (VIP) modeling software. Geostatistical analysis identifies two areas with serious chlorinated solvent contamination. Fate and transport modeling estimates that this contamination will degrade and disperse from the soi… more
Date: August 1998
Creator: Trescott, Jill V. (Jill Virginia)
Partner: UNT Libraries
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Evaluation of a Constructed Wetland to Reduce Toxicity from Diazinon at the Pecan Creek Wastewater Treatment Plant, Denton, TX

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.
Date: May 1996
Creator: Baerenklau, Amy L. (Amy Lyn)
Partner: UNT Libraries
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The Evolution, Applications, and Statistical Interpretations of DNA Typing in Forensic Science

Description: This thesis examines the evolution, applications, and statistical interpretations of DNA typing as a tool in the field of forensic science as well as in our criminal justice system. The most controversial aspect of DNA typing involves the determination of how likely it is that two people share the same DNA profile. This involves the use of population genetics and databases of allelic frequencies as well as some assumptions about population structuring.
Date: August 1997
Creator: Schober, Cassandra C. (Cassandra Carolyn)
Partner: UNT Libraries
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Forest Landscape Dynamics: a Semi-Markov Modeling Approach

Description: A transition model (MOSAIC) is used to describe forest dynamics at the landscape scale. The model uses a semi-Markov framework by considering transition probabilities and Erlang distributed holding times in each transition. Parameters for the transition model are derived from a gap model (ZELIG). This procedure ensures conceptual consistency of the landscape model with the fine scale ecological detail represented by the forest gap model. Spatial heterogeneity in the transition model is driven b… more
Date: August 1997
Creator: Ablan, Magdiel
Partner: UNT Libraries
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Genetics Lecture and Laboratory Syllabus for a Junior-Level Course

Description: The following is a complete syllabus for a college level genetics course. The syllabus contains lecture outlines and notes for each chapter, along with a list of transparencies needed. The quizzes and exams are prepared and placed at the beginning of the syllabus. The beginning of the course will consist of a lecture to introduce the students to the basics of genetics, followed by many applications of genetics. The process of cell division will be mastered by the students, as well as Mendelian … more
Date: August 1999
Creator: Harper, Kasey
Partner: UNT Libraries
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Impacts of the Pyrethroid Insecticide Cyfluthrin on Aquatic Invertibrate Populations in Outdoor Experimental Tanks

Description: The chemical fate and biological impacts of cyfluthrin in aquatic ecosystems were investigated using microcosms (1.9 m^3 concrete tanks) during 1989. Results were compared to a concurrent pesticide registration study using mesocosms (634.7 m^3 earthen ponds). Ten spray drift and five soil runoff simulations were conducted. Pesticide loadings were scaled by system volume, with the same experimental design in ponds and microcosms. Aqueous cyfluthrin concentrations and sediment residue values were… more
Date: May 1992
Creator: Johnson, Philip C. (Philip Charles)
Partner: UNT Libraries
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A Laboratory Study of the Asiatic Clam (Corbicula fluminea Müller) as Influenced by Substrate, Food Source and Water Type

Description: Growth of Corbicula fluminea was monitored in the laboratory. Three experiments were conducted. Experiment I utilized three substrates and one food type. Experiment II utilized three substrates and two food types. Experiments I and II were conducted to determine if substrate type or food type effected growth. Experiment III used no substrates, one food type and was conducted to determine growth response to different types of water. Clams were maintained in three substrates: sand, gravel and cla… more
Date: May 1995
Creator: Halbrook, Courtney (Courtney Ann)
Partner: UNT Libraries
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Landscape Ecological Characteristics of Habitat of the Red-cockaded Woodpecker

Description: Geographic information systems (GIS) technology was used to analyze factors influencing habitat use by an endangered species, the red-cockaded woodpecker. The study area was the western part of the Raven Ranger District of the Sam Houston National Forest, Texas. The factors considered included both structural characteristics and spatial relationships among stands of trees in the habitat.
Date: December 1993
Creator: Thomlinson, John Richard
Partner: UNT Libraries
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