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open access

Investigating Novel Streptomyces Bacteriophage Endolysins as Potential Antimicrobial Agents

Description: As antibiotic resistance has become a major global threat, the World Health Organization has urgently called scientists for alternative strategies for control of bacterial infections. Endolysin, a protein encoded by a phage gene, can degrade bacterial peptidoglycan (PG). Currently, there are three endolysin products in the clinical phase. We, thus, are interested in exploring novel endolysins from Streptomyces phages as only a few of them have been experimentally characterized. Using bioinforma… more
Date: December 2023
Creator: Maneekul, Jindanuch
Item Type: Refine your search to only Thesis or Dissertation

Factors Affecting MeHg Contamination of Spiders and Insect-Mediated MeHg Flux from Human-Made Ponds

Description: The present study focused on methylmercury (MeHg) in emergent aquatic insects and spiders from human-made ponds. This dissertation addresses two main topics: (1) factors affecting variation in spider MeHg concentrations around human-made ponds and (2) the magnitude of MeHg transported out of human-made ponds by emergent aquatic insects (insect-mediated MeHg flux). Spiders were specifically targeted in this study because they have been proposed as sentinels of MeHg contamination (organism whose … more
This item is restricted from view until January 1, 2029.
Date: December 2023
Creator: Hannappel, Madeline Pratt
Item Type: Refine your search to only Thesis or Dissertation

Investigating the Molecular Framesworks of Phloem-Cap Fiber Development in Cotton (Gossypium hirsutum)

Description: The current study focuses on the vascular cambium and the reiterative formation of phloem fiber bundles in cotton stems. The role of the TDIF-PXY-WOX pathway was examined in regulating cambial activity and the differentiation of phloem fibers. A study was conducted to identify and characterize the cotton WOX family genes, focusing on WOX4 and WOX14, aiming to identify and analyze their phylogenetic relationships, tissue-specific expression profiles, functional roles, and metabolic consequences… more
This item is restricted from view until January 1, 2026.
Date: December 2023
Creator: Kaur, Harmanpreet
Item Type: Refine your search to only Thesis or Dissertation
open access

Glucose-Induced Developmental Delay is Modulated by Insulin Signaling and Exacerbated in Subsequent Glucose-Fed Generations in Caenorhabditis elegans

Description: In this study, we have used genetic, cell biological and transcriptomic methods in the nematode C. elegans as a model to examine the impact of glucose supplementation during development. We show that a glucose-supplemented diet slows the rate of developmental progression (termed "glucose-induced developmental delay" or GIDD) and induces the mitochondrial unfolded protein response (UPRmt) in wild-type animals. Mutation in the insulin receptor daf-2 confers resistance to GIDD and UPRmt in a daf-1… more
Date: December 2023
Creator: Nahar, Saifun
Item Type: Refine your search to only Thesis or Dissertation

The Effect of Developmental Hypoxia on Cardiac Physiology in Three Species: Alligator mississippiensis, Chelydra serpentina, and Danio rerio

Description: In this dissertation, I explored the effects of developmental hypoxia on heart contractility in three separate species of ectotherms: the common snapping turtle (Chelydra serpentina), the American alligator (Alligator mississippiensis), and the zebrafish (Danio rerio). I began with the common snapping turtle and tested whether the utilization of the sarcoplasmic reticulum was altered in response to developmental hypoxia. In the next two chapters, developmental hypoxia of the American alligator … more
This item is restricted from view until January 1, 2025.
Date: December 2023
Creator: Smith, Brandt Ragan
Item Type: Refine your search to only Thesis or Dissertation

Suburban Succession and Stream Dynamics

Description: Increasingly higher numbers of people are moving into urbanizing environments, yet our understanding of ecosystem consequences of rapid urbanization is still in its infancy. In this dissertation, I assessed dynamics of residential landscapes during suburban succession and consequences for ecosystem functioning. First, I used a space-for-time approach to quantify more than a century of suburban succession in the Dallas – Fort Worth metroplex (DFW). Attributes of residential landscape plant diver… more
This item is restricted from view until January 1, 2025.
Date: December 2023
Creator: McGillewie, Sara B.
Item Type: Refine your search to only Thesis or Dissertation

Bottom-Up Impacts of Grazing Disturbance on Ground-Nesting Bee Assemblages: Do They Dig It?

Description: In my thesis, I examined impacts of nesting and floral resources on ground-nesting bee assemblages at nine ranch sites with differing grazing histories. Because ecological disturbances can strongly affect the availability of foraging and nesting resources over time, I also examined the impacts of grazing history on nesting and floral resources for ground-nesting bees. I sampled bee assemblages, a comprehensive array of vegetation and soil measures, and floral abundance and richness. I used thes… more
This item is restricted from view until January 1, 2025.
Date: December 2023
Creator: Collins, Shannon Marie
Item Type: Refine your search to only Thesis or Dissertation
open access

Avian Community Response to Riverby Ranch Restoration Reconstruction

Description: Anthropogenic activities have caused many wildlife spices to decline in populations worldwide. The grassland bird communities are especially being impacted by these land use changes. Breeding success is closely tied to functional habitats for most grassland bird species in North Texas. Restoring these degraded habitats is an important component to aid in conserving wildlife biodiversity. We surveyed the bird population at Riverby Ranch Mitigation site by conducting point count sampling. This si… more
Date: December 2023
Creator: Boucher, Tessa Katrish
Item Type: Refine your search to only Thesis or Dissertation

Acute and Sublethal Impacts of Crude Oil Photo-Induced Toxicity in an Early Life Stage Marine Fish (Sciaenops ocellatus) and Invertebrate (Americamysis bahia)

Description: We investigated the modifying effects of ultraviolet (UV) light and chemical dispersant (Corexit 9500A) on crude oil toxicity in juvenile mysids (≤ 24 h) (Americamysis bahia) and larval red drum (24-72 hpf) (Sciaenops ocellatus). These results demonstrate that crude oil toxicity significantly increases with co-exposure to environmentally relevant UV levels in both species, indicating photo-induced toxicity. This toxicity was further exacerbated by the application of chemical dispersants which i… more
This item is restricted from view until January 1, 2025.
Date: December 2023
Creator: Leads, Rachel Renee
Item Type: Refine your search to only Thesis or Dissertation

Proteomic-Based Assessment of Estrogenic Endocrine Disruption in Hyalella azteca

Description: In our studies, we used the environmentally important crustacean Hyalella azteca (H. azteca) as an invertebrate model and 17β-estradiol (E2) as a representative of environmental estrogenic endocrine disrupting compounds (EDCs) for proteomics-based investigations of endocrine disruptions in an aquatic ecosystem. Using liquid chromatography coupled with tandem mass spectrometry, our investigation focused for the first time on the recognition of biological and molecular events affected by E2 expos… more
This item is restricted from view until January 1, 2029.
Date: December 2023
Creator: Prokai, Marcel Laszlo
Item Type: Refine your search to only Thesis or Dissertation

Fatty Acid Amide Hydrolases in Upland Cotton (Gossypium hirsutum L.) and the Legume Model Medicago truncatula

Description: Fatty acid amide hydrolase (FAAH) is a widely conserved amidase in eukaryotes, best known for inactivating the signal of N-acylethanolamine (NAE) lipid mediators. In the plant Arabidopsis thaliana, FAAH-mediated hydrolysis of NAEs has been associated with numerous biological processes. Recently, the phylogenetic distribution of FAAH into two major branches (group I and II FAAHs) across angiosperms outside of Arabidopsis (and in other Brassicaceae), suggests a previously unrecognized complexity … more
This item is restricted from view until January 1, 2025.
Date: December 2023
Creator: Arias Gaguancela, Omar Paul
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

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

Production and Optimization of Para-Hydroxybenzoic Acid (pHBA) in Algae Using Metabolic Engineering and Genomics Approaches

Description: Microalgae being photosynthetic and having quick growth cycles can prove to be excellent candidates as biofactories for the production of aromatic compounds like para-hydroxybenzoic acid (pHBA) that act as a monomer in liquid crystal polymers. We developed transgenic lines of the model alga Chlamydomonas reinhardtii by performing nuclear transformation using electroporation. The transgenic cell lines expressed the ubiC gene that utilized chorismate from the shikimate pathway as a substrate to p… more
Date: December 2021
Creator: Saxena, Garima Girish
Item Type: Refine your search to only Thesis or Dissertation

Reduced Visceral Fat and Biological Indices of Inflammation Following Combined Prebiotic/Probiotic Supplementation in Free Living Adults

Description: Probiotics/prebiotic supplementation represents a viable option for addressing systemic inflammation and chronic disease risk resulting from excessive body weight. The purpose of this feasibility study was to determine if 90-d of supplementation with prebiotic and probiotic could alter mRNA responsible for inflammation and subsequently metabolic health in weight stable overweight adults. Participants were advised to not change their diet or exercise habits during the study. All protocols were a… more
Date: December 2021
Creator: Tanner, Elizabeth A.
Item Type: Refine your search to only Thesis or Dissertation
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