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Linkage of the Nitrilase-Encoding Nit1C Gene Cluster to Cyanotrophy in Acinetobacter haemolyticus

Description: The Nit1C cluster is a conserved gene cluster of seven genes that confers bacterial growth on cyanide as the sole nitrogen source. Bacteria with this ability are referred to as cyanotrophs. To date, the linkage between Nit1C and cyanotrophy has only been demonstrated for environmental isolates but the cluster also exists in certain medically related bacteria. In this study, a nosocomial isolate, Acinetobacter haemolyticus ATCC 19194, carrying Nit1C also displayed the ability to grow on cyanide.… more
This item is restricted from view until August 1, 2028.
Date: July 2023
Creator: Dale, Layla Momo
Partner: UNT Libraries
open access

Air Breathing Fish: Development of Air Breathing in Bristlenose Plecos (Ancistrus cirrhosus)

Description: The bristlenose pleco (Ancistrus cirrhosus) is a species of armored catfish in the Loricariidae family that breathes air facultatively when the aquatic environment becomes hypoxic. The bristlenose pleco uses its highly vascularized stomach as an air breathing organ. The two main goals of this developmental study were to determine the size of onset of air breathing and to determine the frequency of air breathing behavior in bristlenose plecos from juveniles to adults. Developing juveniles reach … more
Date: July 2023
Creator: Crowder, Lauren Whitney
Partner: UNT Libraries
open access

Hypoxia-Induced Cardiac Arrest Alters Central Nervous System Concentrations of the GLYT2 Glycine Transporter in Zebrafish (Danio rerio)

Description: Hypoxia as a stressor has physiological implications that have been a focal point for many physiological studies in recent years. In some studies, hypoxia had large effects on the organ tissue degeneration, which ultimately effects multiple ecological processes. These organ tissue studies played a part in the development of new fields like neurocardiology, a specialty that studied the relationship between the brain and the heart. This thesis focuses on how hypoxia-induced cardiac arrest alte… more
Date: July 2023
Creator: Auzenne, Alexis
Partner: UNT Libraries
open access

Conservation, Connectivity, and Coexistence: Understanding Corridor Efficacy in Fragmented Landscapes

Description: Conservation corridors, areas of land connecting patches of natural land cover, are frequently cited and implemented as a restorative strategy to counteract fragmentation. Current corridor ecology focuses on experimental corridor systems or designed and built conservation corridors to assess functionality. Such systems and designs are typically short, straight swaths of homogenous land cover with unambiguous transitions between patches. Quantifying the degree to which amorphous landscape config… more
Date: May 2023
Creator: Long, Amanda M.
Partner: UNT Libraries
open access

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.
Partner: UNT Libraries

Combined Effects of Polycyclic Aromatic Hydrocarbons and Ultraviolet Light on Benthic and Pelagic Macroinvertebrates

Description: Crude oil commonly enters freshwater aquatic ecosystems as thin sheens forming on the water surface. Oil contains mixtures of toxic compounds called polycyclic aromatic hydrocarbons (PAHs), some of which are known to be photodynamic, increasing toxicity when combined with ultraviolet radiation. Benthic macroinvertebrate communities are commonly utilized as bioindicators, and as such rely on abundant data in literature concerning benthic macroinvertebrates' relative tolerances to a wide range of… more
Date: May 2023
Creator: Chapman, Abigail L.
Partner: UNT Libraries
open access

Ecological Responses to Severe Flooding in Coastal Ecosystems: Determining the Vegetation Response to Hurricane Harvey within a Texas Coast Salt Marsh

Description: Vegetative health was measured both before and after Hurricane Harvey using remotely sensed vegetation indices on the coastal marshland surrounding Galveston Island's West Bay. Data were recorded on a monthly basis following the hurricane from September of 2005 until September of 2019 in order to document the vegetation response to this significant disturbance event. Both initial impact and recovery were found to be dependent on a variety of factors, including elevation zone, spatial proximity … more
Date: August 2021
Creator: Hudman, Kenneth Russell
Partner: UNT Libraries

Studies on the Fibrinolytic Pathway in Zebrafish

Description: Fibrinolysis pathway is an important mechanism for dissolution of fibrin clot by the action of plasmin which is formed from plasminogen, a zymogen via the action of plasminogen activators, i.e. tissue plasminogen activator and urinary plasminogen activator. The regulation of fibrinolysis system in vivo is maintained by plasminogen activators and natural inhibitors i.e. α2-antiplasmin, α2-macroglobulin, Thrombin-activatable fibrinolysis inhibitor (TAFI) and plasminogen activator inhibitor 1 and … more
Date: August 2021
Creator: Gill, Jaspreet Kaur
Partner: UNT Libraries
open access

The Effects of Probiotics on Growth, and Metabolism in Juvenile Oreochromis mossambicus (Mozambique Tilapia)

Description: Improving growth, lowering mortality rates, and having a faster turnaround to harvest is essential for the future of commercial aquaculture. The primary goal of this study was to determine if introducing a single strain probiotic Lactobacillus rhamnosus IMC 501 into the feed regimen of a commercially important aquaculture freshwater fish, Mozambique tilapia (Oreochromis mossambicus), would decrease mortality; change metabolic rates; and increase tissue wet mass (MW), standard length, growth rat… more
Date: May 2020
Creator: Anderson, Michael Earl
Partner: UNT Libraries
open access

Comparative Resistomics of Ancient and Modern Human Microbiomes

Description: Increased exposure to antibiotics has led to the dissemination of genes conferring resistance to antimicrobial metabolites throughout human microbiomes globally via horizontal gene transfer (HGT). This has resulted in the emergence of new resistant strains leading to a rising epidemic of deaths from previously treatable infections. Evidence suggests that before the age of anthropogenic antibiotic use, microbes living within a community produced antibiotic metabolites and, subsequently, maintain… more
Date: August 2020
Creator: Johnson, Sarah
Partner: UNT Libraries

Peregrine Falcon (Falco peregrinus) Subspecies Phylogenomics Using Whole Genome Re-Sequencing

Description: Peregrine falcon subspecies taxonomy is widely debated due to uncertainty in their evolutionary history and unresolved phylogenetic reconstruction using both morphological and molecular data. Previous genetic work has shown limited support for subspecies taxonomy largely as a result of molecular markers used, potential contemporary gene flow, incomplete lineage sorting, and ancestral polymorphisms. With the advent of next-generation sequencing, the cost of generating large amounts of sequence d… more
Date: December 2020
Creator: Meeks, Garrett W.
Partner: UNT Libraries

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
Partner: UNT Libraries
open access

Flow-Recruitment Relationships of Smallmouth Buffalo (Ictiobus bubalus) in Three Texas River Basins

Description: This project focused on the relationship between instream flows and smallmouth buffalo (Ictiobus bubalus) recruitment in the Gulf Coastal Plain of Texas. The flow regime is the dominant factor in lotic systems and, consequently, the relationship between instream flows, including impacts to natural flow regimes, and life-history is a subject of growing interest. Smallmouth buffalo is a good model to investigate the relationship between river flows and variable interannual recruitment success of … more
Date: August 2021
Creator: Reeves, Cole Griffin
Partner: UNT Libraries

Metabolic Responses to Crude Oil during Very Early Development in the Zebrafish (Danio rerio)

Description: The present study sought to determine some morphological and physiological critical windows during very early development in zebrafish exposed to crude oil. I hypothesized that exposed zebrafish would present a decrease in survival rate and body mass, and an increase in routine oxygen consumption (ṀO2), and critical oxygen tension (PCrit). To test these hypotheses, zebrafish were acutely exposed (24 h) during different days of development (1 to 6 days post-fertilization, dpf) to different conce… more
Date: August 2020
Creator: Vazquez Roman, Karem Nathalie
Partner: UNT Libraries

A Genetic Assessment of the Mating System of a Suburban Red-Shouldered Hawk Population in Southwest Ohio

Description: Considering the high reproductive investment of the social male and the cost to the female of losing this benefit by soliciting copulations outside the social pair bond, it is expected that most raptor populations would exhibit low to no occurrence of extra-pair paternity (EPP). This holds true for the majority of raptor species studied to date with only one exception of an urban Cooper's hawk (Accipiter cooperii) study which reported an unexpectedly high extra-pair young frequency of 19.29%. I… more
Date: May 2021
Creator: Wrona, Anna Maria
Partner: UNT Libraries
open access

Sociality in Harris's Hawks Revisited: Patterns of Reproductive Output and Delayed Dispersal

Description: In the lower Rio Grande Valley of south Texas, more than half the nesting groups of Harris's hawks (Parabuteo unicinctus) include at least one auxiliary group member in addition to a breeding pair. To provide further insight into cooperatively breeding raptors, I evaluated sociality in Harris's hawks through the dual benefits framework. I explored the formation, structure, and stability of cooperative group formation across a spatially variable study area, which includes high levels of urbaniza… more
Date: August 2021
Creator: Gibbons, Andrea L
Partner: UNT Libraries

A Test of the Female Mimicry Hypothesis in Painted Buntings (Passerina ciris)

Description: While female mimicry and lower status signaling hypotheses of delayed plumage maturation have received much discussion in the literature, the experimental tests of these hypotheses have been infrequent. Those experimental tests often use a simulated intruder method with artificial model intruders rather than using live conspecific birds as intruders. Subadult male painted buntings (Passerina ciris) possess delayed plumage maturation where they appear visually identical to adult females during t… more
Date: May 2021
Creator: Gurley, Christine E
Partner: UNT Libraries
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.
Partner: UNT Libraries

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
Partner: UNT Libraries
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.
Partner: UNT Libraries

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
Partner: UNT Libraries
open access

Analysis of N-Acylethanolamines in the Oilseed Crop Camelina sativa

Description: To better understand the nature and function of N-acylethanolamines (NAEs) in Camelina sativa, we used mass spectrometry analysis to identify and quantify NAE types in developing seeds, desiccated seeds and seedlings. Developing seeds showed a differential increase in individual NAE species and an overall increase in NAE content with seed development and maturation. The NAE composition in mature, desiccated seeds mostly reflected the total fatty acid composition in the seed tissues, except fo… more
Date: August 2020
Creator: Corley, Chase D
Partner: UNT Libraries

Storm Water Retention Ponds: An Important Source of Aquatic Macroinvertebrate Diversity in a Semi-Arid Urban Landscape of Denton, Texas

Description: The City of Denton, located in a semi-arid region of Texas, has over 200 manmade ponds within its city limits. Many of these ponds, located in densely populated areas, are engineered to control storm water runoff. There is a general lack of recognition of the value these waters contribute to regional biodiversity and as greenspaces. This study, conducted in Denton, is monitoring habitat variables and macroinvertebrate diversity in a series of ponds selected to represent a gradient of urban in… more
Date: May 2020
Creator: Moore, Sabrina
Partner: UNT Libraries
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
Partner: UNT Libraries
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