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Construction of a Physical Map of Moraxella (Branhamella) catarrhalis Strain ATCC25238 (open access)

Construction of a Physical Map of Moraxella (Branhamella) catarrhalis Strain ATCC25238

In order to gain a better understanding of this microorganismand its role in human pathogenesis, a physical map of Moraxella catarrhalis type strain ATCC25238 was constructed using pulsed field gel electrophoresis (PFGE) in combination with Southern hybridization techniques. Restriction endonucleases Not I, Rsr II, and Sma I were used to digest the chromosomal DNA. An overlapping circular map was generated by cross-hybridization of isolated radiolabeled fragments of Moraxella catarrhalis genomic DNA to dried PFGE gels. The number and location of the 16S and 23S ribosomal RNA genes were determined by digestion with l-Ceul enzyme and by Southern hybridization. Virulence-associated genes, the gene for β-lactamase, and housekeeping genes were also placed onto the physical map.
Date: May 1999
Creator: Nguyen, Kim Thuy
System: The UNT Digital Library
Evaluation of a Constructed Wetland to Reduce Toxicity from Diazinon at the Pecan Creek Wastewater Treatment Plant, Denton, TX (open access)

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

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)
System: The UNT Digital Library
A Comparison of Predicted and Actual Trophic Status of Lake Ray Roberts, Texas Based on Chlorophyll A (open access)

A Comparison of Predicted and Actual Trophic Status of Lake Ray Roberts, Texas Based on Chlorophyll A

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 means and were at the mesotrophic-eutrophic boundary of the OECD model. Six years after impoundment, observed MSE chlorophyll a for Main Body, was closer to its predicted mean and in the eutrophic category of the OECD model. Six years after impoundment, Elm Fork arm was the most productive area of Lake Ray Roberts. Observed means of chlorophyll a, total phosphates, suspended solids and turbidity were often highest in the Elm Fork arm. Wastewater effluent from Gainesville and Valley View, TX, had an impact on productivity in Elm Fork arm.
Date: May 1999
Creator: Lytle, Lili Lisa
System: The UNT Digital Library
A Two Semester Life Science Syllabus for Use in Texas Public Schools with Seventh Grade Students (open access)

A Two Semester Life Science Syllabus for Use in Texas Public Schools with Seventh Grade Students

The problem of using a state adopted textbook written to apply to a large body of students with varying interests and needs was overcome by using a detailed syllabus that arranged course content in a meaningful sequence that appealed to student interest. The outlined syllabus prepared a two semester life science curriculum to be used by the teacher to guide lesson planning. Both semesters were divided into three units each. Materials included in the syllabus were given to actual student groups in real classroom settings. Since hands on learning was an important part of classroom instruction, two laboratory sections were included in the appendices to be used with the syllabus.
Date: May 1995
Creator: Edwards, Gail G. (Gail Graham)
System: The UNT Digital Library
Development and Application of an Assessment Protocol for Watershed Based Biomonitoring (open access)

Development and Application of an Assessment Protocol for Watershed Based Biomonitoring

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 Contribution of Dipterans. Once the protocol was developed, it was used to assess the Bayou Chico tributaries and watershed. All three tributaries had been significantly impacted by human activity as had the watershed as a whole. This study indicates that a regional protocol could be developed and is appropriate for biomonitoring at the watershed scale.
Date: May 1998
Creator: Schwartz, Joseph Howard
System: The UNT Digital Library
Responses of Cultured Neuronal Networks to the Cannabinoid Mimetic Anandamide (open access)

Responses of Cultured Neuronal Networks to the Cannabinoid Mimetic Anandamide

The effects of cannabinoid agonists on spontaneous neuronal network activity were characterized in murine spinal cord and auditory cortical cultures with multichannel extracellular recording using photoetched electrode arrays. Different cultures responded reproducibly with global decreases of spiking and bursting to anandamide and methanandamide, but each agonist showed unique minor effects on network activity. The two tissues responded in a tissue-specific manner. Spontaneous activity in spinal tissue was terminated by 1 μM anandamide and 6.1 μM methanandamide. Cortical activity ceased at 3.5 μM and 2.8 μM respectively. Irreversible cessation of activity was observed beyond 8 μM for both tissues and test substances. Palmitoylethanolamide, demonstrated that CB2 receptors were not present or not responsive. However, the data strongly suggested the presence of CB1 receptors.
Date: May 1998
Creator: Morefield, Samantha I. (Samantha Irene)
System: The UNT Digital Library
Short Term Effects of External Electric Fields on Electrical Activity of the Pineal Gland in Rats (open access)

Short Term Effects of External Electric Fields on Electrical Activity of the Pineal Gland in Rats

The effects of short term exposure (5 minutes) to EEFs at relatively high dosages (10, 25, 39, kV/m) on the electrical activity in rat pineal glands was studied. Daytime and nighttime recordings were taken from an implanted microelectrode in the gland. The data show that (1) both the activity and frequency were enhanced when the animals were exposed to EEFs at 39 kV/m continuously and discontinuously; (2) the later condition yielded a sustained increase (36%) whereas the former a brief (10 sec) increase. This enhancement was statistically significant under both conditions (day and night). The effects observed were thought to be due to membrane alterations either in the pineal gland itself or in the neural inputs to the gland.
Date: May 1996
Creator: Vu, Hung Quoc
System: The UNT Digital Library
Comparison of Heteranthera Dubia (Jacq.) MacM.-associated Macroinvertebrates Between Georgraphical Regions in the United States (open access)

Comparison of Heteranthera Dubia (Jacq.) MacM.-associated Macroinvertebrates Between Georgraphical Regions in the United States

Macroinvertebrates associated with the aquatic plant, water stargrass (Heteranthera dubia), were sampled from 12 waterbodies in four regions of the United States from June to August 2005. Taxa richness, evenness, and diversity were lowest in the Lower Midwest (LMW) region, and higher in Northern sites, especially the Upper Midwest (UMW), and Northeast (NE). While relative abundance varied from site to site and region to region, utilization of the plant by functional groups remained fairly constant. Collector-gatherers consistently comprised the largest portion of invertebrates sampled. The shredder/ herbivore functional group comprised an average of 17 % of total groups. Through an exhaustive literature review, it was found that shredder/ herbivores of water stargrass have not been reported in the literature. Because of this, the herbivore group was analyzed separately and consisted of 2,383 specimens representing 23 species. The most common groups were Rhopalosiphum sp., Nectopsyche spp. and chironomids. No differences were found in herbivore diversity or evenness between sampling regions, but species richness was significantly different.
Date: May 2010
Creator: Harms, Nathan Earl
System: The UNT Digital Library
Modulation of the Coelomic Fluid Protein Profile in the Earthworm, Lumbricus Terrestris, After Exposure to Copper as Copper Sulfate (open access)

Modulation of the Coelomic Fluid Protein Profile in the Earthworm, Lumbricus Terrestris, After Exposure to Copper as Copper Sulfate

Proteomic techniques were used to analyze the protein profile of earthworm, Lumbricus terrestris, coelomic fluid collected by either whole body dissection method or the coelomic cavity puncture method. Data demonstrated that collection of coelomic fluid using the coelomic cavity puncture method protocol resulted in a 32% reduction, 377 +/- 4.5 vs 253+/- 19.9 (p=0.0007), in the number of individual proteins. It was determined that the coelomic cavity puncture method yielded a "cleaner" preparation, one less contaminated with extraneous proteins from intestinal tissue, gut contents, and body wall materials. This protocol was used in all later studies. The same proteomic techniques were used to evaluate the effects that exposure to Cu (1.0 μg/cm2) as CuSO4 had on the earthworm coelomic fluid profile. Comparison of protein profile from exposed earthworms demonstrated a significant reduction in the number of proteins expressed (184 ± 2.64 vs 253 ±19.9 p=0.0192) when compared to control organisms. Cu exposure also resulted in a modulation of the protein profile with treated earthworms expressing 47 new proteins that were not identified in unexposed worm coelomic fluid. Additionally, 116 proteins found in coelomic fluid collected from normal worms were absent in Cu exposed organisms. Finally, 137 proteins were conserved or …
Date: May 2010
Creator: Herring, Reese
System: The UNT Digital Library
Bioconcentration and Morphological Effects of Triclosan on Three Species of Wetland Plants (open access)

Bioconcentration and Morphological Effects of Triclosan on Three Species of Wetland Plants

Triclosan (TCS) is an antimicrobial compound found in several types of common household products. After being washed down the drain, TCS will then end up in the local watershed. Although numerous studies have been conducted to evaluate the fate and effects of TCS in aquatic environments, there have been no studies evaluating the role arbuscular mycorrhizal fungi (AM) play in a plants response to TCS exposure. Three species of wetland plants native North Texas were inoculated with AM spores and exposed to 0, 0.4 g/L and 4.0 g/L TCS concentrations. Root morphology of E. prostrata and S. herbacea showed AM and exposure responses. S. herbacea produced the greatest amounts biomass and TCS bioaccumulation, in all but one treatment. It also displayed opposing results to E. prostrata in measures of root length, root surface area, relative root mass, relative shoot mass and shoot:root ratio. TCS root tissue concentrations increased with increased exposures for both E. prostrata and S. herbacea. Even though E. prostrata had the lowest levels in each measure of biomass production, it had the highest amount of root TCS bioaccumulation in the AM inoculated 4.0 g/L treatment. H. laevis was between the other two species in terms of biomass …
Date: May 2013
Creator: Smith, Caleb M.
System: The UNT Digital Library
Exploring the Evolutionary History of North American Prairie Grouse (Genus: Tympanuchus) Using Multi-locus Coalescent Analyses (open access)

Exploring the Evolutionary History of North American Prairie Grouse (Genus: Tympanuchus) Using Multi-locus Coalescent Analyses

Conservation biologists are increasingly using phylogenetics as a tool to understand evolutionary relationships and taxonomic classification. The taxonomy of North American prairie grouse (sharp-tailed grouse, T. phasianellus; lesser prairie-chicken, T. pallidicinctus; greater prairie-chicken, T. cupido; including multiple subspecies) has been designated based on physical characteristics, geography, and behavior. However, previous studies have been inconclusive in determining the evolutionary history of prairie grouse based on genetic data. Therefore, additional research investigating the evolutionary history of prairie grouse is warranted. In this study, ten loci (including mitochondrial, autosomal, and Z-linked markers) were sequenced across multiple populations of prairie grouse, and both traditional and coalescent-based phylogenetic analyses were used to address the evolutionary history of this genus. Results from this study indicate that North American prairie grouse diverged in the last 200,000 years, with species-level taxa forming well-supported monophyletic clades in species tree analyses. With these results, managers of the critically endangered Attwater's prairie-chicken (T. c. attwateri) can better evaluate whether outcrossing Attwater's with greater prairie-chickens would be a viable management tool for Attwater's conservation.
Date: May 2013
Creator: Galla, Stephanie J.
System: The UNT Digital Library
Evaluating the Habitat Requirements of the Golden Orb Mussel (Quadrula Aurea) for Conservation Purposes (open access)

Evaluating the Habitat Requirements of the Golden Orb Mussel (Quadrula Aurea) for Conservation Purposes

Many freshwater mussels are imperiled, due to a number of interrelated factors such as habitat alteration, degradation of water quality, and impoundments. The Golden Orb mussel (Quadrula aurea, I. Lea, 1859) is endemic to the state of Texas and is currently a candidate for the endangered species list, as the number of known populations has been declining in recent years. Little is currently known about Q. aurea aside from basic distribution data. This study is focused on evaluating a combination of macro-habitat and micro-habitat variables to determine their influence on the distribution and density of this species. Macro-habitat variables, including dominant land cover, surface geology, and soil erodibility factor, did not have a significant relationship with mussel distributions. The best model of micro-habitat variables that impacts the Q. aurea distributions is comprised of relative substrate stability (RSS) at moderate flows and current velocity at low flows. For all mussel species in this study, current velocity at low flows is the primary variable that influences distribution. Q. aurea are associated with habitats where larger sediment particles (large gravel and cobble) help to stabilize the substrate in areas with higher current velocities. An understanding of the preferred habitats for Q. aurea can …
Date: May 2013
Creator: Hammontree, Sarah
System: The UNT Digital Library
Primary Cilia in the Oligodendrocyte Lineage (open access)

Primary Cilia in the Oligodendrocyte Lineage

oligodendrocytes migrate from the corpus callosum into the overlying cortex. The incidence of cilia did not change markedly across age groups, and did not vary consistently with the number of processes per cell, which was used as an indication of the maturation stage of OPCs and young OLs. The mean percent of Olig1 immunopositive (Olig1+) cells having cilia across ages was 33.1% + 16.5%, with all ages combined. In O4+ cells of these mice, 56.7 + 3.6% had primary cilia. If it is the case that adult OLs do not have cilia, the point in the lineage when primary cilia are lost is still unknown. Adult mice that had been injected with cyclopamine to block cilia-dependent Shh signaling were examined to determine whether the rate of generating new OPCs was influenced. In the CC of control mice, the numerical density of Olig1+/BrdU+ cells was 1.29 + 0.07/mm2 was reduced to 0.68 + 0.38/mm2 in the cyclopamine-injected group, and the numerical density of all BrdU+ cells (including both Olig1+ and Olig1- cells) of 4.55 + 1.50/mm2 in the control group was reduced to 3.14 + 1.27/mm2 in the cyclopamine-injected group. However, there were only 2 mice in each group and the …
Date: May 2013
Creator: Hao, Yung-Chia
System: The UNT Digital Library
Examination of the Relationship Between Glucuronic Acid and Vascular Damage in Rats (open access)

Examination of the Relationship Between Glucuronic Acid and Vascular Damage in Rats

The goal of this experiment was to examine the role of glucuronic acid in the development of vascular damage in the kidneys and retinas of diabetic individuals. Glucuronic acid was provided to rats in their water at various concentrations in order to increase plasma levels of the compound. Kidneys and retinas were excised and compared to control specimens using microscopy to determine the effect of elevated blood glucuronic acid levels on the occurrence of microaneurysms in renal capillary networks. No differences were seen between the treatment and control groups. Further study needs to be conducted to determine a more suitable time frame for this experiment.
Date: May 2013
Creator: Moore, Ryan
System: The UNT Digital Library
Genetic Interest Assessment (open access)

Genetic Interest Assessment

Genetics is becoming increasingly integrated into peoples' lives. Different measures have been taken to try and better genetics education. This thesis examined undergraduate students at the University of North Texas not majoring in the life sciences interest in genetic concepts through the means of a Likert style survey. ANOVA analysis showed there was variation amongst the interest level in different genetic concepts. In addition age and lecture were also analyzed as contributing factors to students' interest. Both age and lecture were evaluated to see if they contributed to the interest of students in genetic concepts and neither showed statistical significance. The Genetic Interest Assessment (GIA) serves to help mediate the gap between genetic curriculum and students' interest.
Date: May 2013
Creator: Doughney, Erin
System: The UNT Digital Library
Enallagma civile (Odonata: Coengrionidae) life history and production in a west Texas playa (open access)

Enallagma civile (Odonata: Coengrionidae) life history and production in a west Texas playa

A life history and productivity study of Enallagma civile was conducted in a playa that was located in the southern High Plains of Texas. Other odonates were also studies to identify their contributions to the habitat.
Date: May 2002
Creator: Booker, Jennifer Suzanne
System: The UNT Digital Library
College Freshman Biology Two Semester Course: Integrating Deep Processing Teaching Techniques (open access)

College Freshman Biology Two Semester Course: Integrating Deep Processing Teaching Techniques

Development of a college level freshman biology course was undertaken in response to government reports that American students have fallen behind students of other countries in the area of the sciences. Teaching strategies were investigated to accomplish two objectives, to define essential academic material to include in the course and to investigate teaching techniques that would increase deep processing of the information. An active process that consisted of applying the cognitive information to solving problems or developing answers to questions was defined as critical thinking. Critical thinking was incorporated into the course by the use of case studies.
Date: May 2002
Creator: Blevins, Mary Jean
System: The UNT Digital Library
The Use of Genetic Polymorphisms and Discriminant Analysis in Evaluating Genetic Polymorphisms as a Predictor of Population (open access)

The Use of Genetic Polymorphisms and Discriminant Analysis in Evaluating Genetic Polymorphisms as a Predictor of Population

Discriminant analysis is a procedure for identifying the relationships between qualitative criterion variables and quantitative predictor variables. Data bases of genetic polymorphisms are currently available that group such polymorphisms by ethnic origin or nationality. Such information could be useful to entities that base financial determinations upon predictions of disease or to medical researchers who wish to target prevention and treatment to population groups. While the use of genetic information to make such determinations is unlawful in states and confidentiality and privacy concerns abound, methods for human “redlining” may occur. Thus, it is necessary to investigate the efficacy of the relationship of certain genetic information to ethnicity to determine if a statistical analysis can provide information concerning such relationship. The use of the statistical technique of discriminant analysis provides a tool for examining such relationship.
Date: May 2002
Creator: Howell, Bruce F.
System: The UNT Digital Library
Bacterial Challenge in Lumbricus Terrestris: A Terrestrial Invertebrate Immunotoxicity Model. (open access)

Bacterial Challenge in Lumbricus Terrestris: A Terrestrial Invertebrate Immunotoxicity Model.

A bacterial challenge assay was developed utilizing the earthworm, Lumbricus terrestris, in order to assess potential immunotoxic effects from exposure to specific polychlorinated biphenyl congeners. Earthworms were inoculated with Aeromonous hydrophila, establishing a 10-day LD50. In vitro assays for effects of PCBs on phagocytosis agreed with mammalian studies, demonstrating potent suppression of phagocytosis by the non-coplanar PCB congener 138 and no suppression by the coplanar congener 126. However, when the effects of the two PCB congeners were evaluated for suppression of resistance to a whole animal infection challenge assay, coplanar PCB 126 decreased the ability of L. terrestris to withstand infection while non-coplanar PCB 138 did not.
Date: May 2007
Creator: McDonald, Jennifer C.
System: The UNT Digital Library
Influence of parental swimming stamina on the cardiac and metabolic performance of larval zebrafish (Danio rerio). (open access)

Influence of parental swimming stamina on the cardiac and metabolic performance of larval zebrafish (Danio rerio).

Superior swimming stamina in adult fish is presumably passed on to their offspring, but the ontogeny of the appearance of superior stamina and the requisite enhanced cardio-respiratory support for locomotion in larval fishes has not been determined. Is the expression of the suite of parental traits enabling superior swimming stamina in their offspring dependent upon their achieving juvenile/adult morphology, or does it appear earlier in their larvae? To answer this, adults were classified into three groups based on swimming stamina, followed by measurement of length, mass, and width. Larval offspring from the two parental groups -high stamina larvae (HSL) and low stamina larvae (LSL)- were reared at 27°C in aerated water (21% O2). Routine and active heart rate, routine and active mass specific oxygen consumption were recorded through 21dpf, and cost of transport (COT) and factorial aerobic scope were derived from oxygen consumption measurements. Routine heart rate at 2dpf of LSL was 164 ± 1 b·min-1, compared to only 125 ± 2 b·min-1 for HSL. Routine heart rate subsequently peaked at 203 ± 1 b·min-1 at 5dpf in the HSL group, compared to 207 ± 1 b·min-1, at 4dpf in the LSP larvae. Active heart rate at 5 dpf of …
Date: May 2007
Creator: Gore, Matthew R.
System: The UNT Digital Library
Immunohistochemical characterization of neuronal cilia in the rat central nervous system. (open access)

Immunohistochemical characterization of neuronal cilia in the rat central nervous system.

An anti-G"11 antibody was used to label neuronal cilia throughout the rat central nervous system. Immunoreactive cilia were observed in every examined region of the rat CNS, but not in monkey or mouse tissue. Antibodies to G"q and G"q/11 failed to label cilia. Immunoreactive cilia were observed as early as postnatal day 0 in spinal tissue, and postnatal day 3 in hypothalamic tissue. There was a statistically significant negative correlation between a region's mean cilium length and that region's distance to the nearest ventricle; regions nearest ventricles were those with the longest cilia. This correlation suggests neuronal cilia may function as chemosensors, detecting substances as they move out from the cerebrospinal fluid and into the extracellular space of the brain.
Date: May 2002
Creator: Hughes, Rhome
System: The UNT Digital Library

Macroinvertebrate Community Structure as an Indicator of Watershed Health in the Upper Trinity River Basin, North Central Texas

Access: Use of this item is restricted to the UNT Community
This study describes macroinvertebrate community structure and assesses its potential in detecting point and non-point sources of disturbance associated with rural and urban areas in the Upper Trinity River Basin. Geospatial techniques were used to quantify landuse within the watershed in a GIS. At rural sites near the headwaters of the Trinity River, collector-gathering burrowers that are adapted to minimal flow comprised the majority of taxa. Destinies of taxa compositions at downstream sites increased and shifted toward psammophilic and rheophilic invertebrates, including primarily collector-filtering clingers, that are characteristic of shifting sand habitats in large prairie rivers. Benthic community structure generally benefited from point source impacts including wastewater treatment plant effluents that maintained higher flow. Community indices were negatively associated with forest landuse and positively associated with urban landuse. Partial CCA determined that flow and landuse contributed equally to species dispersions. Comparisons with historical biomonitoring studies in upper Trinity River Basin indicate improved watershed health.
Date: May 2000
Creator: Stephenson, Jaynie M.
System: The UNT Digital Library
Anatomy and Physiology Syllabus for Community Colleges (open access)

Anatomy and Physiology Syllabus for Community Colleges

This syllabus includes both lecture notes and laboratory activities for a two-semester anatomy and physiology community college course. The syllabus is based on a 16-week semester that is comprised of a three-hour lecture section and a one-hour laboratory class each week. Both the lecture course and laboratory are necessary to fulfill the requirement for anatomy and physiology. Laboratory activities coincide with lectures to enhance understanding of each topic by providing visual and hands-on experiments for the concepts learned in the lecture. Laboratory quizzes will be given each week to help students maintain a working knowledge of the material learned in the laboratory. This course is appropriate for the typical anatomy and physiology student and should benefit both students who plan to major in biology and also those who are non-biology majors. Because subject matter in anatomy and physiology is quite difficult, the importance of attendance and good study skills is stressed.
Date: May 2000
Creator: Schulz, Leslie
System: The UNT Digital Library
Effects of Daily Oral Injections of Quercetin on Implanted Colon-25 Tumor Growth in Balb-C Mice (open access)

Effects of Daily Oral Injections of Quercetin on Implanted Colon-25 Tumor Growth in Balb-C Mice

The effects of three oral dosages (0.4 mg, 0.8 mg, and 1.6 mg) of quercetin on Colon-25 tumors implanted in Balb-c mice were studied. The data in this study show that: (1) certain dosages of quercetin in alcohol solutions, reduces the weight, and size of implanted Colon-25 tumors in Balb-c mice, (2) these same dosages of quercetin all produce a profound neutrophilia combined with a significant lymphopenia at day 20 post-implantation, and (3) there was relatively little evidence of histological changes in the quercetin-treated tumor section which would indicate that the action(s) of quercetin is primarily at the subcellular level probably within the nuclei of the tumor cells.
Date: May 2000
Creator: Hayashi, Adam
System: The UNT Digital Library