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open access

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

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 Erpeto… more
Date: May 1999
Creator: Abbott, John C.
Partner: UNT Libraries
open access

Landscape forest modeling of the Luquillo Experimental Forest, Puerto Rico.

Description: This thesis contributes to modeling the dynamics of forest community response to environmental gradients and disturbances over a mountain landscape. A gap model (FACET) was parameterized for species of various forest types (Tabonuco, Colorado, Dwarf and Palm), for many terrain conditions and was modified and extended to include species response to excess soil moisture and hurricanes. Landscape cover types were defined by dominance of species of each forest type and canopy height. Parameters of … more
Date: December 2002
Creator: Abbott-Wood, Chris
Partner: UNT Libraries

Impact of Anti-S2 Peptides on a Variety of Muscle Myosin S2 Isoforms and Hypertrophic Cardiomyopathy Mutants Revealed by Fluorescence Resonance Energy Transfer and Gravitational Force Spectroscopy

Description: Myosin subfragment-2 (S2) is an intrinsically unstable coiled coil. This dissertation tests if the mechanical stability of myosin S2 would influence the availability of myosin S1 heads to actin thin filaments. The elevated instability in myosin S2 coiled coil could be one of the causes for hypercontractility in Familial Hypertrophic Cardiomyopathy (FHC). As hypothesized FHC mutations, namely E924K and E930del, in myosin S2 displayed an unstable myosin S2 coiled coil compared to wild type as mea… more
Date: August 2020
Creator: Aboonasrshiraz, Negar
Partner: UNT Libraries
open access

DNA-DNA Hybridization of Methane Oxidizing Bacteria

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 hybri… more
Date: December 1976
Creator: Ackerson, Jill W.
Partner: UNT Libraries
open access

Integrating Selective Herbicide and Native Plant Restoration to Control Alternanthera philoxeroides (Alligator Weed)

Description: Exotic invasive aquatic weeds such as alligator weed (Alternanthera philoxeroides) threaten native ecosystems by interfering with native plant communities, disrupting hydrology, and diminishing water quality. Development of new tools to combat invaders is important for the well being of these sensitive areas. Integrated pest management offers managers an approach that combines multiple control methods for better control than any one method used exclusively. In a greenhouse and field study, we t… more
Date: December 2011
Creator: Adams, Justin
Partner: UNT Libraries
open access

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

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 tempo… more
Date: August 1986
Creator: Adewusi, Iyabode Olukemi, 1958-
Partner: UNT Libraries
open access

Identification and Characterization of an Arabidopsis thaliana Mutant with Tolerance to N-lauroylethanolamine

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 … more
Date: December 2015
Creator: Adhikari, Bikash
Partner: UNT Libraries
open access

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

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 … more
Date: August 2012
Creator: Adhikari, Prem R.
Partner: UNT Libraries
open access

Solvent Effects and Bioconcentration Patterns of Antimicrobial Compounds in Wetland Plants

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 comp… more
Date: May 2011
Creator: Adhikari, Sajag
Partner: UNT Libraries

Identification, Characterization and Engineering of UDP-Glucuronosyltransferases for Synthesis of Flavonoid Glucuronides

Description: Flavonoids are polyphenolics compounds that constitute a major group of plant specialized metabolites, biosynthesized via the phenylpropanoid/polymalonate pathways. The resulting specialized metabolites can be due to decoration of flavonoid compounds with sugars, usually glucose, by the action of regiospecific UDP-glycosyltransferase (UGT) enzymes. In some cases, glycosylation can involve enzymatic attachment of other sugar moieties, such as glucuronic acid, galactose, rhamnose or arabinose. Th… more
Date: December 2020
Creator: Adiji, Olubu Adeoye
Partner: UNT Libraries
open access

Presence of Wolbachia, A Potential Biocontrol Agent: Screening for Vertebrate Blood Meal Source and West Nile Virus in Mosquitoes in the North Texas Region

Description: West Nile virus (WNV) is a geographically endemic mosquito-borne flavivirus that has spread across the United States infecting birds, mosquitos, humans, horses and other mammals. The wide spread nature of this virus is due to the ability of the mosquito vector to persist in broad, ecological diverse environments across the United States. In this study, mosquito populations in North Texas region were sampled for detection of Wolbachia, blood meal source, and WNV. The ultimate goal of this study … more
Date: August 2016
Creator: Adiji, Olubu Adeoye
Partner: UNT Libraries

Traffic-Generated Air Pollution-Exposure Mediated Expression of Factors Associated with Progression of Multiple Sclerosis in a Female Polipoprotein E Knockout Mouse Model

Description: Environmental air pollution is one risk factor associated with the onset and progression of multiple sclerosis (MS). In this project, we investigated the effects of ubiquitous traffic-generated pollutants, namely a mixture of gasoline and diesel vehicle exhaust (MVE), on signaling pathways associated with the pathophysiology of MS in the central nervous system (CNS) of either ovary intact (ov+) or ovariectomized (ov-) female Apolipoprotein (Apo) E-/-. Specifically, we investigated whether a sub… more
Date: December 2020
Creator: Adivi, Anna
Partner: UNT Libraries
open access

Chronic Ventricular Sympathectomy : Effects on Myocardial Metabolism

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 whic… more
Date: August 1993
Creator: Adix Longlet, Nancy J.
Partner: UNT Libraries

Exploring Flavonoid Glycosylation in Kudzu (Pueraria lobata)

Description: The isoflavones in kudzu roots, especially the C-glycosylated isoflavone puerarin, have been linked to many health benefits. Puerarin contains a carbon-carbon glycosidic bond that can withstand hydrolysis. The C-glycosylation reaction in the biosynthesis of puerarin has not been thoroughly investigated, with conflicting reports suggesting that it could take place on daidzein, isoliquiritigenin, or 2,7,4ʹ-trihydroxyisoflavanone. Kudzu species were identified for use in comparative transcriptomic… more
Date: August 2021
Creator: Adolfo, Laci Michelle
Partner: UNT Libraries

Analysis of the Cytochrome P450 and UDP-Glucuronosyltransferase Families and Vitamin D3- Supplementation in Anoxia Survival in Caenorhabditis elegans

Description: Alteration in diet and knockdown of detoxification genes impacts the response of C. elegans to oxygen deprivation stress. I hypothesized that feeding worms a vitamin D3-supplementation diet would result in differential oxygen deprivation stress response. We used a combination of wet lab and transcriptomics approach to investigate the effect of a vitamin-D3 supplemented diet on the global gene expression changes and the anoxia response phenotype of C. elegans (Chapter 2). C. elegans genome consi… more
Date: December 2020
Creator: Agarwal, Sujata
Partner: UNT Libraries
open access

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

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 … more
Date: May 1993
Creator: Aguilar Pulido, Roberto E. (Roberto Eric)
Partner: UNT Libraries
open access

Immune Response of the Rat to Outer Membrane Proteins of Legionella Pneumophila

Description: Outer membrane proteins (OMPs) were recovered from eleven strains (eight serogroups) of Legionella pneumophila by sequential treatment with Tris buffer (pH 8), citrate buffer(pH 2.75) and Tris buffer (pH 8). Transmission electron microscopy revealed clearly the separation of the outer membrane from the bacteria. The development of delayed hypersensitivity was also noted by measuring the area of arythema and induration produced by intradermal injections of the MPSs from Chicago 8 strain. The adj… more
Date: August 1985
Creator: Ahanotu, Ejemihu Ndu
Partner: UNT Libraries
open access

Determination of Habitat Preferences of Pronghorn (Antilocapra americana) on the Rolling Plains of Texas Using GIS and Remote Sensing

Description: The Rocker b Ranch on the southern Rolling Plains has one of the last sizeable populations of pronghorn (Antilocapra americana) in Texas. To investigate habitat utilization on the ranch, pronghorn were fitted with GPS/VHF collars and were released into pastures surrounded by a variety of fences to determine how fence types affected habitat selection. Habitat parameters chosen for analysis were vegetation, elevation, slope, aspect, and distances to water, roads, and oil wells. Results showed … more
Date: May 2005
Creator: Aiken, Robin A.
Partner: UNT Libraries
open access

Photoactivatable Quantum Dots in Super-Resolution Microscopy of Muscle

Description: Super-resolution 3D imaging was achieved using newly synthesized photoactivatable quantum dot (PAQ dot) probes. Quantum dots were modified with a novel quencher system to make them photoactivatable. The unique properties of these PAQ dots enable single-fluorophore localization in three dimensions using a confocal microscopy optical sectioning method. Myosin and tropomyosin of rabbit myofibrilar bundles were specifically labeled with the newly synthesized PAQ dot. A sufficient number of single q… more
Date: December 2010
Creator: Akel, Amal
Partner: UNT Libraries

Role of MicroRNAs and Their Downstream Targets in Zebrafish Thrombopoiesis

Description: Previous studies have shown that human platelets and megakaryocytes carry microRNAs suggesting their role in platelet function and megakaryocyte development, respectively. However, there is limited information on microRNAs' role in zebrafish thrombopoiesis. Zebrafish thrombocytes could be used as a model to study their role in megakaryocyte maturation and platelet function because thrombocytes have both megakaryocyte features and platelet properties. In our laboratory, I identified 15 microRNAs… more
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Date: May 2023
Creator: Al Qaryoute, Ayah
Partner: UNT Libraries
open access

Degradation of Phenolic Acids by Azotobacter Species Isolated from Sorghum Fields

Description: Sorghum plants excrete phenolic acids which reduce subsequent crop yields. These acids accumulate in field soil by combining with soil and clay particles to form stable complexes which remain until degraded by bacterial metabolism. The amount of phenolic acids in soil samples were obtained by gas chromatography measurements, while Azotobacter populations were obtained by plate counts in 40 sorghum field samples from Denton County, Texas. One can conclude that increasing the Azotobacter populati… more
Date: August 1989
Creator: Al-Hadhrami, Mohamed N. (Mohamed Nasser)
Partner: UNT Libraries
open access

Site Directed Mutagenesis of Dienelactone Hydrolase

Description: The clcD gene encoding dienelactone hydrolase (DLH) is part of the clc gene cluster for the utilization of the B-ketoadipate pathway intermediate chlorocatechol. The roles that individual amino acids residues play in catalysis and binding of the enzyme were investigated. Using PCR a 1.9 kbp clcD fragment was amplified and subcloned yielding a 821 bp BamHi to ZscoRI subclone in the plasmid pUC19.
Date: August 1995
Creator: Al-Khatib, Haifa Yousef
Partner: UNT Libraries
open access

The Physiology of Azotobacter Vinelandii Cysts

Description: The value of the adenylate energy charge [(ATP)+1/2(ADP)/(ATP)+(ADP)+(AMP)] in Azotobacter vinelandii cells was monitored during growth and germination in flask cultures. The miximal value of 0.88 was attained during mid-log phase; this declined gradually to 0.50 by late stationary phase. When these cultures were transferred to encystment media, the adenylate energy charge decreased to an average value of 0.40 as the vegetative cells encysted and remained unchanged during the next 20 days. Ency… more
Date: December 1980
Creator: Aladegbami, Solomon L.
Partner: UNT Libraries
open access

Effects of Phytohormones on Scenedesmus quadricauda

Description: The literature on the effects of phytohormone on algae is clouded with contradictory reports. Reports have been published which substantiate and deny the effects of phytohormones in enhancing the growth and developmental processes in algae. The overall aim of this study was to investigate the response, if any, of the phytohormones indole-3-acetic acid (IAA), gibberellic acid A3 (GA) and kinetin on the physiology of the green alga, Scenedesmus quadricauda. Results obtained for the uptake of 14^C… more
Date: August 1977
Creator: Alam, Mohammad Ihtisham
Partner: UNT Libraries
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