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Greater, Lesser, Guessers: A Look into the Hybridization of Greater and Lesser Prairie-Chickens

Description: My thesis focuses on the conservation consequences of the hybridization of Lesser Prairie-Chickens in Kansas. Specifically, examining how past land management practices altering the species ranges impact the distinctiveness of Lesser Prairie-Chickens. Each chapter is an individual publication that addresses if the Greater and Lesser Prairie-Chicken are distinct when applying the morphological and biological species concepts. Chapter 2 compares the evolutionary history and morphological construc… more
Date: May 2023
Creator: Stein, Carleigh M.
Item Type: Refine your search to only Thesis or Dissertation

Identification and Characterization of Two Putative Sulfate Transporters Essential for Symbiotic Nitrogen Fixation in Medicago truncatula

Description: The process of symbiotic nitrogen fixation (SNF) in legume root nodules requires the channeling and exchange of nutrients within and between the host plant cells and between the plant cells and their resident rhizobia. Using a forward genetics approach in the Medicago truncatula Tnt1 mutant population followed by whole genome sequencing, two putative sulfate transporter genes, MtSULTR3;5 and MtSULTR3;4b, were identified. To support the hypothesis that the defective putative sulfate transporter … more
This item is restricted from view until January 1, 2025.
Date: December 2022
Creator: Pradhan, Rajashree
Item Type: Refine your search to only Thesis or Dissertation

Developing Informatics Tools and Methods Utilizing Whole Genome Sequencing and Transcription Data to Aid Gene Discovery in Medicago truncatula

Description: Research into the mechanism of symbiotic nitrogen fixation between legumes and rhizobia involves a complex interaction between the organisms, and many genes involved in this remain either uncharacterized or undiscovered. Using forward genetics, mutant plant lines are screened to find new genes without reliance on software-based gene prediction. A large population of Tnt1-mutagenized Medicago truncatula lines is used for this purpose. Herein, the aid of tools like whole genome sequencing (WGS) i… more
This item is restricted from view until January 1, 2025.
Date: December 2022
Creator: Troiani, Taylor
Item Type: Refine your search to only Thesis or Dissertation

Investigating the Spatial Relationship between Suicide and Race/Ethnicity: The Case for Alternate Rate Adjustment Techniques in Medical Geography

Description: This work explores potential distortions created by race and ethnicity on the visualization, interpretation, and understanding of the spatial distribution of suicide in the United States. Due to radically different suicide rates among racial/ethnic groups, traditional crude or age-adjusted rates may introduce statistical confounding in both linear and spatial models. Using correlation, choropleth mapping, hot spot analysis, and location-allocation modeling, this work shows how traditional metho… more
Date: December 2022
Creator: Lester, Katherine Ann
Item Type: Refine your search to only Thesis or Dissertation

Developing a Generalizable Two-Input Genetic AND Logic Gate in Arabidopsis thaliana for Multi-Signal Processing

Description: With effective engineering using synthetic biology approaches, plant-based platforms could conceivably be designed to minimize the production costs and wastes of high-value products such as medicines, biofuels, and chemical feedstocks that would otherwise be uneconomical. Additionally, modern agricultural crops could be engineered to be more productive, resilient, or restorative in different or rapidly changing environments and climates. To achieve these complex goals, information-processing ge… more
Date: December 2022
Creator: Anderson, Charles Edgar
Item Type: Refine your search to only Thesis or Dissertation

Data Mining Using Direct Injection Triple Quadrupole Mass Spectrometry, Infrared Spectroscopy, Inductively Coupled Plasma Optical Emission Spectroscopy, and Polymerase Chain Reaction for the Rapid Identification of Nutraceuticals and Contaminants

Description: There has been a rapid surge toward "organic" products devoid of GMOs, MSGs, and other common compounds found in processed foods that continue to indicate an association with an increased risk for disease. These consumers seek nutrients and vitamins that are lacking in their diet and lifestyle in the form of nutraceuticals for disease prevention and treatment as well as overall lifestyle enhancement. However, these products generally lack clinical evidence as well as legal definition. Due to th… more
Date: December 2022
Creator: Yazici, Micayla Rose Morgan
Item Type: Refine your search to only Thesis or Dissertation
open access

Migration Tracking, Survival, and Pairing Behavior of American Kestrels Wintering in North Central Texas

Description: The American Kestrel (Falco sparverius) is the smallest and most abundant falcon in North America with a wide geographic range. Unfortunately, surveys have suggested that some kestrel populations have been in decline since the 1950s, though the nominal causes of this decline are unknown. Migratory movement patterns and connectivity have yet to be established for any population of migratory kestrels. In Chapter 2, I investigated methods for attaching migration trackers to kestrels. Specifically,… more
Date: December 2022
Creator: Biles, Kelsey S
Item Type: Refine your search to only Thesis or Dissertation

Alterations in the Expression of Proteins Associated with Non-Alcoholic Fatty Liver Disease Observed in the Liver of the C57Bl/6 Wild-Type Male Mouse in Response to Exposure of Mixed Vehicle Emissions and/or High Fat Diet Consumption

Description: Recent epidemiological studies have demonstrated a correlation between the manifestation of non-alcoholic fatty liver disease (NAFLD) and ambient air pollution levels, which is exacerbated by the presence of other risk factors, such as diabetes, dyslipidemia, obesity, and hypertension. We investigated the hypothesis that exposure to a mixture of gasoline and diesel engine emissions (MVE) coupled with the concurrent consumption of a high-fat (HF) diet promotes the development of a NAFLD phenotyp… more
This item is restricted from view until January 1, 2025.
Date: December 2022
Creator: Schneider, Leah Jayne
Item Type: Refine your search to only Thesis or Dissertation
open access

Space Use, Microhabitat and Macrohabitat Use of the Three-Toed Box Turtle (Terrapene carolina) in North Texas

Description: Box turtle (Terrapene carolina) populations are steadily declining due their unique natural history, effects of climate change, and anthropogenic land use change. There is a need for updated information on box turtle space and micro and macro-habitat use to inform conservation efforts. This study used VHF radiotelemetry and GPS data loggers to examine box turtle space and habitat use in North Texas. Box turtle home range sizes averaged 6.6ha (range = 0.79 - 18.08, n = 23), and males (n = 9) had… more
Date: December 2022
Creator: Joseph, Sara A.
Item Type: Refine your search to only Thesis or Dissertation

Medicago truncatula NPF1.7: Structure-Function Assessment and Potential as a Phytohormone Transporter

Description: In Medicago truncatula, the MtNPF1.7 transporter has been shown to be essential for root morphology and nodulation development. The allelic MtNPF1.7 mutants, Mtnip-1 (A497V), Mtnip-3 (E171K), and Mtlatd (W341STOP), show altered lateral root growth and compromised legume-rhizobium symbiosis. To assess the role of a series of distinct amino acids in the transporter's function, in silico structural predictions were combined with in planta complementation of the severely defective Mtnip-1 mutant pl… more
Date: December 2022
Creator: Yu, Yao Chuan
Item Type: Refine your search to only Thesis or Dissertation
open access

Seeing in the Light: Using Expansion Microscopy to Achieve Super-Resolution in Transmitted Light

Description: Light microscopy is inherently limited in resolution by properties of light such as diffraction and interference to 170-250 nm. Expansion microscopy is a quickly-developing method which achieves super-resolution by using a swellable hydrogel to physically expand biological samples themselves, rather than depending on the properties of fluorophores. This thesis demonstrates that expansion microscopy is a feasible means for achieving super-resolution in transmitted light microscopy modes. Though … more
Date: December 2022
Creator: Migliore, Julia R.
Item Type: Refine your search to only Thesis or Dissertation
open access

Multi-Level Effects of Oxygen Exposure in Endothermic Insects

Description: This dissertation examined the phenotypic plasticity of endothermic, flight and respiratory physiology in response to developmental oxygen exposure in the moth Manduca sexta. Development in both 10% O2 hypoxia and 30% O2 hyperoxia treatments were used to look at the physiological consequence on both ends of the oxygen spectrum. Hypoxic insects reached smaller sizes as adults and had longer pupation lengths than controls. Hyperoxic insects were larger at the end of the larval stage, had increase… more
Date: August 2022
Creator: Wilmsen, Sara M
Item Type: Refine your search to only Thesis or Dissertation

Inferring a Network of Horizontal Gene Flow among Prokaryotes Using Complementary Approaches

Description: Horizontal gene transfer (HGT), a mechanism that facilitates exchange of genetic material between organisms from different lineages, has a profound impact on prokaryotic evolution. To infer HGT, we first developed a comparative genomics-based tool, APP, which can perform phyletic pattern analysis using completely sequenced genomes to identify genes are unique to a genome or have sporadic distribution in its close relatives. Performance assessment against currently available tools on a manually … more
This item is restricted from view until September 1, 2024.
Date: August 2022
Creator: Sengupta, Soham
Item Type: Refine your search to only Thesis or Dissertation
open access

Acute Toxicity of Crude Oil Exposures to Early Life Stage Teleosts: Contribution of Impaired Renal Function and Select Environmental Factors

Description: Oil spills are well-known adverse anthropogenic events, as they can induce severe impacts on the environment and negative economic consequences. Still, much remains to be learned regarding the effects of crude oil exposure to aquatic organisms. The objectives of this dissertation were to fill some of those knowledge gaps by examining the effects of Deepwater Horizon (DWH) crude oil exposure on teleost kidney development and function. To this end, I analyzed how these effects translate into pote… more
Date: August 2022
Creator: Bonatesta, Fabrizio
Item Type: Refine your search to only Thesis or Dissertation

A Sensitive and Robust Machine Learning-Based Framework for Deciphering Antimicrobial Resistance

Description: Antibiotics have transformed modern medicine in manifold ways. However, the misuse and over-consumption of antibiotics or antimicrobials have led to the rise in antimicrobial resistance (AMR). Unfortunately, robust tools or techniques for the detection of potential loci responsible for AMR before it happens are lacking. The emergence of resistance even when a strain lacks known AMR genes has puzzled researchers for a long time. Clearly, there is a critical need for the development of novel app… more
This item is restricted from view until September 1, 2024.
Date: August 2022
Creator: Sunuwar, Janak
Item Type: Refine your search to only Thesis or Dissertation

Regulation of Receptors in Neuronal Cilia with Development, Seizures, and Knockouts: Implications for Excitability

Description: Neurons commonly have a primary cilium, which is a non-motile organelle extending from the centrosome into the extracellular space. In most brain regions, neuronal cilia are enriched in either somatostatin receptor type 3 (SstR3) or melanin concentrating hormone receptor type 1 (MCHR1), or both. The present immunohistochemical study provides novel evidence that primary cilia regulate neuronal excitability via G-protein coupled receptors (GPCRs), and that their identity is governed by brain re… more
This item is restricted from view until September 1, 2027.
Date: August 2022
Creator: Shrestha, Jessica
Item Type: Refine your search to only Thesis or Dissertation
open access

Assessing Student Perceptions in Short Research Experiences and Course Research Experiences in Undergraduate Biology Laboratories

Description: This study examined students' perception between short research experiences (SRE) courses and full-semester course research experiences (CRE) using the Persistence in the Sciences (PITS) survey and the interview questionnaire. The study also aimed to correlate the influence of student's demographic as a predictive indicator for Project Ownership Scores (POS) and Quantitative Literacy (QL) score means. The three courses studied at the University of North Texas were Biology for Science Majors Lab… more
Date: August 2022
Creator: Alberts, Arland Dulcey
Item Type: Refine your search to only Thesis or Dissertation

Temperature Change and Its Consequences for the Physiology of the Eurythermic Sheepshead Minnow (Cyprinodon variegatus)

Description: The estuarine sheepshead minnow (Cyprinodon variegatus) is the most eurythermic fish species, with a thermal tolerance window between 0.6°C and 45.1°C. However, little is known about the physiological mechanisms that allow this species to survive this temperature range. In order to understand how sheepshead minnow physiology is affected by temperature acclimation and acute changes in temperature, I conducted research on this species using a multi-level approach. I began at the organismal level,… more
Date: August 2022
Creator: Reynolds, Amanda Caroline
Item Type: Refine your search to only Thesis or Dissertation

Investigation of Gene Functions in the Cyanotrophic Bacterium Pseudomonas fluorescens NCIMB 11764

Description: Pseudomonas fluorescens NCIMB 11764 (Pf11764) is one of a group of bacteria known as cyanotrophs that exhibit the unique ability to grow on toxic cyanide as the sole nitrogen source. This ability has previously been genetically linked to a conserved cluster of seven genes (Nit1C), the signature gene (nitC) coding for a nitrilase enzyme. Nitrilases convert nitriles to ammonia and a carboxylic acid. Still, for the Pf11764 NitC enzyme (Nit11764), no in vivo substrate has been identified, and the… more
This item is restricted from view until June 1, 2027.
Date: May 2022
Creator: Gullapalli, Jaya Swetha
Item Type: Refine your search to only Thesis or Dissertation

Metacommunity Dynamics of Medium- and Large-Bodied Mammals in the LBJ National Grasslands

Description: Using metacommunity theory, I investigated the mechanisms of meta-assemblage structure and assembly among medium- to large-bodied mammals in North Texas. Mammals were surveyed with camera-traps in thirty property units of the LBJ National Grasslands (LBJNG). In Chapter II the dispersal and environmental-control based processes in community assembly were quantified within a metacommunity context and the best-fit metacommunity structure identified. A hypothesis-driven modelling approach was used … more
Date: May 2022
Creator: McCain, Wesley Craig Stade
Item Type: Refine your search to only Thesis or Dissertation

Ecosystem Services and Sustainability: A Framework for Improving Decision-Making in Urban Areas

Description: Ecosystem services are the varied goods and benefits provided by ecosystems that make human life possible. This concept has fostered scientific explorations of the services that nature provides to people with the goal of sustaining those services for future generations. As the world becomes increasingly urban, ecosystems are reshaped, and services are degraded. Provisioning and regulating ecosystem services, landscape planning, decision making, and agricultural systems and technologies play a d… more
This item is restricted from view until June 1, 2024.
Date: May 2022
Creator: Valencia Torres, Angélica
Item Type: Refine your search to only Thesis or Dissertation
open access

Correlation of Watershed NDVI Values to Benthic Macroinvertebrate Biodiversity in Eight North American Wadeable Streams

Description: Water quality of a stream or river is influenced by the surrounding landscape and vegetation. The Normalized Difference Vegetation Index (NDVI) is commonly used to characterize landcover and vegetation density. Benthic macroinvertebrates are ubiquitous in freshwater streams and are excellent indicators of the quality of freshwater habitats. Data from one NDVI remote sensing flight and one macroinvertebrate sampling event for eight wadeable stream study sites in the National Ecological Observ… more
Date: May 2022
Creator: Gallagher, Denice Lynne
Item Type: Refine your search to only Thesis or Dissertation

Role of DEFECTIVE IN SYSTEMIC DEFENSE INDUCED BY ABIETANE DITERPENOID 1 (DSA1), a Putative O-Fucosyltransferase, in Plant Systemic Acquired Resistance (SAR)

Description: Dehydroabietinal (DA), an abietane diterpenoid, was previously demonstrated to be a potent activator of systemic acquired resistance (SAR). DA also promotes flowering time in Arabidopsis thaliana by repressing expression of the flowering repressor FLOWERING LOCUS C (FLC) while simultaneously upregulating expression of FLOWERING LOCUS D (FLD), FLOWERING LOCUS VE (FVE) and RELATIVE OF EARLY FLOWERING 6 (REF6), a set of flowering time promoters. To further understand the mechanism underlying signa… more
This item is restricted from view until June 1, 2024.
Date: May 2022
Creator: Mohanty, Devasantosh
Item Type: Refine your search to only Thesis or Dissertation

Influence of Hypoxia on Acute Lead Toxicity and Calcium Homeostasis in Early Life Stage Zebrafish (Danio rerio)

Description: The purpose of this study was to investigate the effects of Pb and hypoxia co-exposure on Pb toxicity and Ca homeostasis in early life stage (ELS) zebrafish (Danio rerio). Previous evidence indicates that exposure of ELS zebrafish to hypoxia (~20% air saturation) reduces Ca uptake, likely through down-regulation of the apical epithelial Ca channel (ECaC). Considering that Pb and Ca are known antagonists and compete for uptake pathways, it was hypothesized that co-exposure of Pb with hypoxia wou… more
Date: December 2021
Creator: Moghimi, Mehrnaz
Item Type: Refine your search to only Thesis or Dissertation
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