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 Department: Department of Biological Sciences
 Degree Level: Doctoral
 Collection: UNT Theses and Dissertations
Biodiversity of Dragonflies and Damselflies (Odonata) of the South-Central Nearctic and Adjacent Neotropical Biotic Provinces

Biodiversity of Dragonflies and Damselflies (Odonata) of the South-Central Nearctic and Adjacent Neotropical Biotic Provinces

Date: May 1999
Creator: Abbott, John C.
Description: The south-central United States serves as an important biogeographical link and dispersal corridor between Nearctic and Neotropical elements of western hemisphere odonate faunas. Its species are reasonably well known because of substantial collections, but there has been no concerted effort to document the extent of biodiversity and possible geographic affinities of dragonflies and damselflies of this region. The recent discoveries of Argia leonorae Garrison, Gomphus gonzalezi Dunkle and Erpetogomphus heterodon Garrison from southern and western Texas and northern Mexico suggest that Odonata species remain to be discovered in this area, particularly from far south Texas and northern Mexico. I have documented a total of 12,515 records of Odonata found in 408 counties within the south-central U.S. A total of 73 species of damselflies and 160 species of dragonflies was revealed in the region. The 233 (197 in Texas) Odonata species are distributed among 10 families and 66 genera. Illustrated family, generic, and species-level keys are provided. Since the beginning of this work in the Fall of 1993, one species has been added each to the Louisiana and Oklahoma faunas, and 12 species have been added, previously unreported from Texas, including four new to the U.S. The area of highest Odonata ...
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The Eosinophil and Lysophospholipase Responses in Mice Infected with Trichinella spiralis: A Role for the Lymphocyte and Macrophage

The Eosinophil and Lysophospholipase Responses in Mice Infected with Trichinella spiralis: A Role for the Lymphocyte and Macrophage

Date: August 1986
Creator: Adewusi, Iyabode Olukemi, 1958-
Description: The relationship among eosinophils, lysophospholipase activity and the immune response in animals infected with Trichinella spiralis was studied using in vivo and in vitro techniques. In an in vivo experiment, anti-thymocyte serum (ATS) was administered to mice infected with T. spiralis and its effects on intestinal lysophospholipase (EC 3.1.1.5.) activity, peripheral blood, bone marrow and intestinal eosinophilia were measured in the same experimental animal. The ATS caused a significant temporally related suppression of both the tissue lysophospholipase response and eosinophilia, in all three compartments. These findings support the hypothesis that parasite-induced eosinophilia is the cause of the increased lysophospholipase activity of parasitized tissue and that the responses are thymus cell-dependent. In vitro experiments demonstrated that the eosinophil was the primary inflammatory cell source of lysophospholipase among eosinophils, neutrophils macrophages and lymphocytes. The role of other cells and antigen in the production of the enzyme by the eosinophil was also investigated in vitro• Results demonstrated that eosinophils cultured with both T. spiralis antigen and other leukocytes yielded enzyme activities significantly greater than eosinophils cultured alone or with only antigen. More specific experiments showed that T-lymphocytes were the cells responsible for influencing the eosinophils' lysophospholipase activity in the presence of antigen, and ...
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Identification and Characterization of an Arabidopsis Thaliana Mutant with Tolerance to N-lauroylethanolamime

Identification and Characterization of an Arabidopsis Thaliana Mutant with Tolerance to N-lauroylethanolamime

Date: December 2015
Creator: Adhikari, Bikash
Description: N-Acylethanolamines (NAEs) are fatty acid derivatives in plants that negatively influence seedling growth. N-Lauroylethanolamine (NAE 12:0), one type of NAE, inhibits root length, increases radial swelling of root tips and reduces root hair numbers in a dose dependent manner in Arabidopis thaliana L. (ecotype Columbia). A forward genetics approach was employed by screening a population of T-DNA “activation-tagged” developed by the Salk Institute lines for NAE resistance to identify potential genes involved in NAE signaling events in Arabidopsis thaliana L. (ecotype Columbia). Seeds of the activation tagged lines were grown at 0, 25, 30, 50, 75 and 100 µM N-lauroylethanolamime (NAE 12:0). Ten plants which displayed NAE tolerance (NRA) seedling phenotypes, compared with wildtype (Columbia, Col-0) seedlings were identified. I focused on one mutant line, identified as NRA 25, where the tolerance to NAE 12:0 appears to be mediated by a single dominant, nuclear gene. Thermal asymmetric interlaced (TAIL) PCR identified the location of the T-DNA insert as 3.86 kbp upstream of the locus At1g68510. Quantitative PCR indicated that the transcript level corresponding to At1g68510 is upregulated approximately 20 fold in the mutant relative to wildtype. To determine whether the NAE tolerance in NRA 25 is associated with overexpression of ...
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Proteomic Responses in the Gill of Zebrafish Following Exposure to Ibuprofen and Naproxen

Proteomic Responses in the Gill of Zebrafish Following Exposure to Ibuprofen and Naproxen

Date: August 2012
Creator: Adhikari, Prem R.
Description: Non-steroidal anti-inflammatory drugs (NSAIDs) are among the most abundant environmental pharmaceutical contaminants. In this study, a proteomic analysis was conducted to identify proteins differentially expressed in gill tissue of zebrafish (Danio rerio) after a 14-day exposure to the NSAIDs ibuprofen or naproxen. A total of 104 proteins with altered expression as indicated by 2-dimensional electrophoresis were analyzed by liquid chromatography with ion trap mass spectrometry (MS/MS). A total of 14 proteins fulfilled our requirements for identification which included consistency among replicate gels as well as successful MS/MS ion searches with the MASCOT database. The most prominent feature of the differential protein expression observed after NSAID exposure was an up-regulation of proteins belonging to the globin family which are involved in the transport of oxygen from gills and availability of heme molecules required for synthesis of cyclooxygenase. Differential expression was observed at exposure concentrations as low as 1-10 µg/L indicating that altered gene expression may occur in fish subjected to environmentally realistic levels of NSAID exposure.
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Chronic Ventricular Sympathectomy : Effects on Myocardial Metabolism

Chronic Ventricular Sympathectomy : Effects on Myocardial Metabolism

Date: August 1993
Creator: Adix Longlet, Nancy J.
Description: Chronic ventricular sympathectomy elicits changes in the coronary circulation, myocardial oxygen consumption and size of infarction resulting fromcoronary occlusion. These changes indicate a change occurring in the basic metabolism of the heart in response to the removal of its sympathetic nervous input. This hypothesis was tested using two groups of dogs, a shamoperated control and a ventricular sympathectomized group. The sympathectomy procedure was an intrapericardial surgical technique which selectively removes ventricular sympathetic input. Four weeks after surgery, left ventricular tissue samples were obtained and rapidly frozen to -80°C. Selected metabolic variables were then compared between the two groups.
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Nesting Ecology and Reproductive Correlates in the Desert-nesting Gray Gull Larus Modestus

Nesting Ecology and Reproductive Correlates in the Desert-nesting Gray Gull Larus Modestus

Date: May 1993
Creator: Aguilar Pulido, Roberto E. (Roberto Eric)
Description: General objectives of my study were to describe the reproductive ecology of gray gulls in the large Lealtad colony, with emphasis on demographic parameters and physiological adaptations of eggs and chicks, which would complete some original objectives established in the early 1980's by Guerra and Fitzpatrick. Specifically, my study focused on describing, then comparing with other desert and non-desert nesting larids, interactive effects of ambient physical conditions and nest-site predation on eggs and chicks.
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Development of a Procedure to Evaluate Groundwater Quality and Potential Sources of Contamination in the East Texas Basin

Development of a Procedure to Evaluate Groundwater Quality and Potential Sources of Contamination in the East Texas Basin

Access: Use of this item is restricted to the UNT Community.
Date: May 2001
Creator: Alderman, John H.
Description: This study contributes a procedure, based on data analysis and geostatistical methods, to evaluate the distribution of chemical ratios and differentiate natural and anthropogenic contaminant sources of groundwater quality in the East Texas Basin. Four aquifers were studied, Sparta, Queen City, Carrizo and Wilcox. In this study, Carrizo- Wilcox is considered as one aquifer, and Sparta-Queen City as another. These aquifers were divided into depth categories, 0-150 feet for Sparta-Queen City and 300-600 feet and 600-900 feet for Carrizo-Wilcox in order to identify individual sources of contamination. Natural sources include aquifer mineral make up, salt domes and lignite beds. Major anthropogenic sources include lignite and salt dome mining and oil-gas production. Chemical ratios selected were Na/Cl, Ca/Cl, Mg/Cl, SO4/Cl, (Na+Cl)/TDS, SO4/Ca and (Ca+Mg)/(Na+K). Ratio distributions and their relationships were examined to evaluate physical-chemical processes occurring in the study area. Potential contaminant sources were used to divide the Basin into three areas: Area 1 to the east, Area 2 in the west and Area 3 in the center. Bivariate analysis was used to uncover differences between the areas. The waters in Area 1 are potentially impacted primarily from oil field waters. Sources present in Area 2 include lignite beds and oil ...
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Development, Validation, and Evaluation of a Continuous, Real-time, Bivalve Biomonitoring System

Development, Validation, and Evaluation of a Continuous, Real-time, Bivalve Biomonitoring System

Access: Use of this item is restricted to the UNT Community.
Date: December 2002
Creator: Allen, H. Joel
Description: A biological monitoring tool to assess water quality using bivalve gape behavior was developed and demonstrated. The purpose of this work was to develop methodologies for screening water quality appropriate to the goals of the watershed paradigm. A model of bivalve gape behavior based on prediction of behavior using autoregressive techniques was the foundation of the bivalve biomonitoring system. Current technology was used in developing the system to provide bivalve gape state data in a continuous real-time manner. A laboratory version of the system, including data collection and analysis hardware and software, was developed for use as a toxicological assay for determination of effective concentrations of toxicant(s) or other types of stress on bivalve gape behavior. Corbicula fluminea was monitored and challenged with copper, zinc, and chlorpyrifos using the system. Effective concentrations of 176±23µg/L copper, 768±412µg/L zinc, and 68µg/L chlorpyrifos were observed using a natural water with high dissolved organic carbon concentrations. A rugged field version of the bivalve biomonitoring system was developed and deployed in two locations. The field systems were fitted with a photovoltaic array, a single board computer, and a CDPD telemetry modem for robust remote operation. Data were telemetered at a time relevant rate of once ...
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Investigation of Strategies for Improving STR Typing of Degraded and Low Copy DNA from Human Skeletal Remains and Bloodstains

Investigation of Strategies for Improving STR Typing of Degraded and Low Copy DNA from Human Skeletal Remains and Bloodstains

Date: August 2014
Creator: Ambers, Angie D.
Description: Forensic STR analysis is limited by the quality and quantity of DNA. Significant damage or alteration to the molecular structure of DNA by depurination, crosslinking, base modification, and strand breakage can impact typing success. Two methods that could potentially improve STR typing of challenged samples were explored: an in vitro DNA repair assay (PreCR™ Repair Mix) and whole genome amplification. Results with the repair assay showed trends of improved performance of STR profiling of bleach-damaged DNA. However, the repair assay did not improve DNA profiles from environmentally-damaged bloodstains or bone, and in some cases resulted in lower RFU values for STR alleles. The extensive spectrum of DNA damage and myriad combinations of lesions that can be present in forensic samples appears to pose a challenge for the in vitro PreCR™ assay. The data suggest that the use of PreCR™ in casework should be considered with caution due to the assay’s varied results. As an alternative to repair, whole genome amplification (WGA) was pursued. The DOP-PCR method was selected for WGA because of initial primer design and greater efficacy for amplifying degraded samples. Several modifications of the original DOP-PCR primer were evaluated. These modifications allowed for an overall more robust amplification ...
Contributing Partner: UNT Libraries
Engineered Microbial Consortium for the Efficient Conversion of Biomass to Biofuels

Engineered Microbial Consortium for the Efficient Conversion of Biomass to Biofuels

Date: August 2014
Creator: Anieto, Ugochukwu Obiakornobi
Description: Current energy and environmental challenges are driving the use of cellulosic materials for biofuel production. A major obstacle in this pursuit is poor ethanol tolerance among cellulolytic Clostridium species. The first objective of this work was to establish a potential upper boundary of ethanol tolerance for the cellulosome itself. The hydrolytic function of crude cellulosome extracts from C. cellulolyticum on carboxymethyl cellulose (CMC) with 0, 5, 10, 15, 20 and 25% (v/v) ethanol was determined. Results indicated that the endoglucanase activity of the cellulosome incubated in 5% and 10% ethanol was significantly different from a control without ethanol addition. Furthermore a significant difference was observed in endoglucanase activity for cellulosome incubated in 5%, 10%, 15%, 20% and 25% ethanol in a standalone experiment. Endoglucanase activity continued to be observed for up to 25% ethanol, indicating that cellulosome function in ethanol will not be an impediment to future efforts towards engineering increasing production titers to levels at least as high as the current physiological limits of the most tolerant ethanologenic microbes. The second objective of this work was to study bioethanol production by a microbial co-culture involving Clostridium cellulolyticum and a recombinant Zymomonas mobilis engineered for the utilization of oligodextrans. The ...
Contributing Partner: UNT Libraries
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