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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
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
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
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

Analysis of Multipartite Bacterial Genomes Using Alignment-Free and Alignment-Based Pipelines

Description: In this work, we have performed comparative evolutionary analysis, functional genomics analysis, and machine learning analysis to identify the molecular factors that discriminate between multipartite and unipartite bacteria, with the goal to decipher taxon-specific factors and those that are prevalent across the taxa underlying the these traits. We assessed the roles of evolutionary mechanisms, namely, horizontal gene transfer and gene gain, in driving the divergence of bacteria with single and… more
Date: August 2021
Creator: Almalki, Fatemah
Item Type: Refine your search to only Thesis or Dissertation
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
Item Type: Refine your search to only Thesis or Dissertation
open access

Analysis of the Accumulation, Toxic Effects, and Risk of Persistent Organic Pollutants in Pinnipeds

Description: The present studies determine the accumulation of persistent organic pollutants (POPs) in three pinniped species, evaluate the relationship with relevant biomarkers of exposure, and calculate toxic effect thresholds. Stranded harp and hooded seals were found to be accumulating PBDEs at levels which could pose a based on threshold levels determined in this study. Northern fur seals are accumulating all three classes of POPs (PCBs, PBDEs, and OCPs) with significant relationships being seen with b… more
Date: August 2021
Creator: Soulen, Brianne K
Item Type: Refine your search to only Thesis or Dissertation

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
Item Type: Refine your search to only Thesis or Dissertation
open access

Anti-S2 Peptides and Antibodies Binding Effect on Myosin S2 and Anti-S2 Peptide's Ability to Reach the Cardiomyocytes in vivo and Interfere in Muscle Contraction

Description: The anti-S2 peptides, the stabilizer and destabilizer, were designed to target myosin sub-fragment 2 (S2) in muscle. When the peptides are coupled to a heart-targeting molecule, they can reach the cardiomyocytes and interfere with cardiac muscle contraction. Monoclonal antibodies, MF20 and MF30, are also known to interact with light meromyosin and S2 respectively. The MF30 antibody compared to anti-S2 peptides and the MF20 antibody is used as a control to test the central hypothesis that: Both … more
Date: July 2023
Creator: Quedan, Duaa Mohamad Alhaj Mahmoud
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
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

Benefits of Probiotics on Mortality, Growth Performance, Physiological Condition and Gut Histomophology of Juvenile Red Drum (Sciaenops ocellatus)

Description: Results from the present study found for the first time that the use of bacterial strains of Lactobacillus acidophilus, Lactobacillus casei, Bifidobacterium thermophilum, and Enterococcus faecium from the commercial product PrimaLac® had the potential to act as a possible probiotic for juvenile red drum. The addition of PrimaLac® probiotics [whether as a water-soluble probiotic (WSP) or in a probiotic enhanced starter feed (PESF)] reduced mortality (%M), enhanced growth rates (MW, LT, SGR, and … more
Date: May 2021
Creator: Busby, Wren Adell
Item Type: Refine your search to only Thesis or Dissertation

Biomonitoring at Dallas-Fort Worth International Airport: Relating Watershed Land Use with Aquatic Life Use

Description: The Dallas-Fort Worth International (DFW) Airport is located in a densely urbanized area with one of the fastest-growing populations in the U.S.A. The airport property includes a large tract of "protected" riparian forest that is unique to the urban surroundings. This dissertation explores variables that influence the benthic macroinvertebrate community structure found in urbanized prairie streams that were initially assessed by the University of North Texas (UNT) Benthic Ecology Lab during fou… more
Date: August 2021
Creator: Harlow, Megann Mae Lewis
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

Breeding Ecology and Migratory Connectivity of Passerines in the World's Southernmost Forests

Description: In the extensive and remote sub-Antarctic forests of South America, birds are the dominant terrestrial vertebrates. Despite considerable efforts to understand the ecology of birds breeding in these forests, our current knowledge for many species is still incomplete. During three breeding seasons (2014 – 2017), I studied the breeding ecology of the five most abundant open-cup forest-dwelling passerines in the sub-Antarctic forest of Navarino Island, Chile (55°04′S, 67°40′W). There were differenc… more
Date: May 2021
Creator: Jara Millar, Rocio Fernanda
Item Type: Refine your search to only Thesis or Dissertation
open access

CO2 Transport and Acid-Base Status during Fluctuations in Metabolic Status in Reptiles

Description: Reptiles can often experience perturbations that greatly influence their metabolic status (e.g., temperature, exercise, digestion, and ontogeny). The most common cause of fluctuations in metabolic status in post-embryonic reptiles is arguably digestion and physical activity (which will be further referred to as exercise). The objective of this thesis is to determine the mechanisms involved in CO2 transport during digestion, determine the mechanisms that allow for the maintenance of acid-base ho… more
Date: December 2021
Creator: Conner, Justin Lawrence
Item Type: Refine your search to only Thesis or Dissertation

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
This item is restricted from view until June 1, 2024.
Date: May 2023
Creator: Chapman, Abigail L.
Item Type: Refine your search to only Thesis or Dissertation
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
Item Type: Refine your search to only Thesis or Dissertation

Conducting Tick-Borne Disease Research in Texas with a Focus on Rickettsia spp.

Description: The field of vector-borne disease research uses multidisciplinary approaches to help understand complicated interactions. This dissertation, covers three different aspects of tick-borne disease research which all focus on exploring tick-borne diseases in the non-endemic areas of Denton, County Texas and the state of Texas with a focus on Rickettsia spp. These aspects include tick sampling, testing ticks for the presence of Rickettsia spp., and creating species distribution maps of the Rickettsi… more
Date: May 2020
Creator: Huddleston, Jody Sue
Item Type: Refine your search to only Thesis or Dissertation

The Consequences of Early Life Stage Thyroid Suppression on Immune Function in the Fathead Minnow (Pimephales promelas)

Description: Current evidence suggests that thyroid hormones (THs) may impact development of the immune system. However, studies that explore the role of THs in immune development are limited, and the mechanisms leading to alterations in immune function are poorly understood. It is important to elucidate the role of THs in immune development given that many environmental contaminants have been shown to disrupt TH homeostasis and may also have negative impacts on the immune system. As such, the main goal of … more
Date: May 2020
Creator: Thornton Hampton, Leah Marie
Item Type: Refine your search to only Thesis or Dissertation
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.
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

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

Detection and Classification of Cancer and Other Noncommunicable Diseases Using Neural Network Models

Description: Here, we show that training with multiple noncommunicable diseases (NCDs) is both feasible and beneficial to modeling this class of diseases. We first use data from the Cancer Genome Atlas (TCGA) to train a pan cancer model, and then characterize the information the model has learned about the cancers. In doing this we show that the model has learned concepts that are relevant to the task of cancer classification. We also test the model on datasets derived independently of the TCGA cohort and s… more
Date: July 2023
Creator: Gore, Steven Lee
Item Type: Refine your search to only Thesis or Dissertation
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