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Impact Of Retinoic Acid Receptor Alpha Conditional Knockout On Ovarian Follicle Development In The Mouse, Zlata Bogin

College of Science and Health Theses and Dissertations

When there is abnormal endocrine signaling in the follicles, infertility, and ovarian diseases such as polycystic ovarian syndrome (PCOS), premature ovarian failure (POF), and different types of ovarian cancers may occur. Retinoic acid (RA), a biologically active derivative of vitamin A, is a critical signaling molecule that plays a vital role in various physiological processes, including embryonic development, tissue differentiation, and reproductive function. RA has been observed to influence granulosa cell proliferation through a cell signaling cascade involving Retinoic Acid Receptors (RARs), which have three isoforms alpha, beta, and gamma. We characterized a new retinoic acid receptor alpha (RARA) conditional …

Investigating The Salinity Tolerance Of The Swordtail (Xiphophorus Hellerii), Alexandra Megan Krak

College of Science and Health Theses and Dissertations

The swordtail, Xiphophorus hellerii, is a freshwater fish species native to Mexico and Central America and is commonly used in the tropical aquarium trade. Swordtails have been shown to have limited survival in 6 ‰ salinity (Nanda et al., 2016), suggesting they may have a greater salinity tolerance than previously expected. Using a gradual acclimation method, we examined the salinity tolerance and swim performance of this species. Freshwater-reared female swordtails were housed in 29-gallon aquaria. A control group was held in freshwater throughout the experiment. For the experimental group, the salinity was increased by 2 ‰ every week until 30 …

Characterization Of The Immune Deficiency Pathway During Female Meiosis In Drosophila Melanogaster, Sarah Mashburn

College of Science and Health Theses and Dissertations

Organisms can defend against pathogens by significantly increasing the diversity of their progeny, so that some progeny are more likely to survive infection. This led to the prediction that infection should cause an increase in recombination rates which was seen in a previous study. However, the mechanism that regulates recombination rates in response to infection is not understood and in that study they did not provide a mechanism for how that can occur. In an RNAi screen, our lab found the gene mustard (mtd) is required for normal recombination rates. This gene was previously shown to be part of the …

Observations Of 25 Ghz Methanol Masers In W51a, Peter Wagstaff

College of Science and Health Theses and Dissertations

High mass stars are important because they alone are responsible for creating the heavy elements in the Universe. The observation of high mass star formation remains a challenging problem in astronomy because high mass stars form in densely clustered environments at large distances from us. Therefore, high angular resolution observations are required to unravel the action taking place in these dense environments. Masers can be used to observe distant regions with high angular resolution because masers are compact and bright sources. Class I methanol masers are believed to form in outflows from protostars where the shock generated by the outflowing …

Attention Visual, Baris Dingil

College of Computing and Digital Media Dissertations

This research presents an innovative approach to improving visual-spatial attention using a research tool based on the web. Recognizing the significant role visual-spatial attention plays in everyday life and cognitive function for humans, this research was undertaken with the aim of developing a user-friendly, accessible web-based tool called Attention Visual (attentionvisual.com) to enhance this crucial cognitive skill. This tool also facilitates data collection, potentially accelerating the pace and enhancing the quality of related research. Both qualitative and quantitative methods were utilized for data collection and analysis. In order to stimulate improvements in visual-spatial attention, the tool’s algorithm was structured to …

Spatiotemporal Dynamics Of Ticks And Tick-Borne Disease At Neon Sites Across A Sub-Continental Scale, Ana Sofia Rivera

College of Science and Health Theses and Dissertations

Tick-borne diseases in humans such as Lyme disease cases in the United States have doubled between 2004 and 2016. Understanding the dynamics of infectious diseases has long been of interest for ecologists. Tick and tick-borne diseases are influenced by temperature and precipitation at local scales, indirectly through mast seeding in forest trees which increases the abundance of tick hosts (e.g., small mammals), as well as direct effects on survival. Most tick studies occur at local scales that comprise only a small part of their range. The aim of my thesis is to characterize spatiotemporal dynamics of ticks and tick-borne diseases …

Temperature Effects On The Development Of The Axial Skeleton And Body Shape In Astyanax Mexicanus (Teleostei: Characidae), Joseph David Forberg

College of Science and Health Theses and Dissertations

Humans are causing large-scale changes in environmental conditions across the planet including in temperature. Changes in the environmental conditions can lead to phenotypic changes in ectotherms that affect adaptively important traits like body shape and the axial skeleton. Previous studies have shown that temperature changes during development significantly affects body shape and vertebral number in the Mexican tetra Astyanax mexicanus. How these changes arise early in development is not clear. In this study, I examine how changes in developmental temperature affect body shape in larval and juvenile fish, the order of ossification of elements of the axial skeleton, the size …

Characterization Of A Stenotrophomonas Maltophilia Bacteriophage, Edward Eshoo

College of Science and Health Theses and Dissertations

Stenotrophomonas maltophilia is a ubiquitous Gram-negative, multidrug resistant, opportunistic bacterial pathogen that causes various infections in humans. Recently, the use of bacteriophages as therapeutic agents, has gained interest as an alternative to traditional antibiotics. This thesis describes the isolation, purification, and characterization of S. maltophilia bacteriophage Bfi2 and discusses its activity against related, and often co-isolated, bacterial pathogens. Amplification of the phage resulted in clear, well-defined plaques and a titer of 1.73 ± 0.38 x 1011 PFU/ml. Bfi2 demonstrated the ability to lyse 55% of the S. maltophilia strains tested, suggesting that it has a moderate host range. However, the …

Niche Overlap In Sympatric Rocio (Teleostei: Cichlidae) Of Guatemala, Cesar Estuardo Fuentes Montejo

College of Science and Health Theses and Dissertations

Rocio is a small genus of Neotropical freshwater fishes that is distributed in Atlantic drainages of northern Middle America. Two species in the genus exhibit sympatry in the Río Dulce basin (in Izabal, Guatemala), where one species is endemic (R. spinosissima), while the other only includes this area as part of a larger geographic range (R. octofasciata). Unfortunately, the ecology of these species has been poorly studied. This study sought to determine the ecological and morphological differences between these two closely related sympatric freshwater fishes. We hypothesized that R. octofasciata would exhibit greater ecological and morphological …

Hiding Behind The Title: Bridging The Gap Between Identity And Leadership Through Neuroscience, Emotional Intelligence And Ethical Management, Alicia S. Huddleston

College of Education Theses and Dissertations

Leadership is the key determinant in the success of any organization, and leaders have an immeasurable impact on the lives and performances of those they have been entrusted to develop, support and lead. School principals are an integral part of the leadership tapestry within society and many people have been impacted by a school principal. Often enough, there are individuals who lead with or behind their title versus understanding first who they are intrinsically, and then working through those dynamics to effectively lead their own lives. When leaders are able to do this, then and only then are they equipped …

The Effects Of Triaminopyrimidine Analogs And Gold(I) Chloride Compounds On Cell Proliferation And Apoptosis In Mda-Mb-231 Human Breast Cancer Cells, Robin Redline

College of Science and Health Theses and Dissertations

Breast cancer is a common disease that affects both women and men all over the world. Triple negative breast cancer is an aggressive subtype of breast cancer with poor survival statistics and few available treatment options. Uncontrolled cell proliferation and the ability to avoid programmed cell death, apoptosis, are two shared hallmarks of cancers. Previous research has shown a group of heterocyclic molecules called triaminopyrimidines, not tested in this study, may be effective antiproliferative agents. Previous research has also shown that some gold(I) complexes not tested in this study, may be promising anticancer agents. In this study, a few chemicals …

Phylogenomics And Population History Of Cichlid And Live-Bearing Fish Species In Lowland Neotropical Rivers, Konrad Taube

College of Science and Health Theses and Dissertations

Within Middle America, cichlids and poeciliids account for more than half of the fish biodiversity. This richness in fish fauna highlights the complexity of Middle American biogeography: no other continental area on earth contains within its range the unparalleled abundance of secondary freshwater fish species (fish that can tolerate both saltwater and freshwater). Research into the biogeography of widely distributed Middle American freshwater fish is essential to understanding this unique region.

Three species of freshwater fishes (Belonesox belizanus – Pike killifish, Vieja maculicauda – Black belt cichlid, and Gambusia nicaraguensis – Nicaraguan mosquitofish) are widely distributed across rivers on …

Patterns Of Torso Morphology In Extant Quadrupedal Amniotes And Their Paleontological Applications, Myles M.A. Walsh

College of Science and Health Theses and Dissertations

The relationship between form and function is an overarching theme in the field of biology. Specifically, body size and shape are important factors when considering the biology of an organism. This study examined the torso morphology of a diverse set of 124 extant terrestrial and semi-aquatic amniote taxa using a novel approach to construct approximated torso shape groupings. My study shows the presence of 10 distinct torso shapes within the examined amniotes, and these torso shape groupings were used to evaluate hypotheses associated with diet and limb bone length as well as explore potential evolutionary patterns. Herbivores had a more …

Lgbtqia+ Care Simulation: Examining Participating Students’ Attitude And Comfort, Grezelro Gonzalez

College of Science and Health Theses and Dissertations

Background: The LGBTQIA+ communities face healthcare disparities that contribute to reduced overall health. One factor affecting LGBTQIA+ communities’ reduced overall health is poor health-promoting behaviors or avoidance of care due to healthcare providers’ lack of knowledge, poor attitude, and low comfort levels with LGBTQIA+ care. There are limited studies to date that address nursing students’ attitude and comfort with LGBTQIA+ affirming care interventions outside of lectures. Therefore, the purpose of this study was to evaluate the effect of a simulation intervention on the attitude and comfort of prelicensure nursing students towards providing care to members of the LGBTQIA+ community. Sample: …

Fossil Vertebrates From A Unique Marine Bonebed Of The Upper Cretaceous Niobrara Chalk, Western Kansas, U.S.A.: New Insights Into The Niobrara Vertebrate Paleoecology, Jonathan Allen

College of Science and Health Theses and Dissertations

The Smoky Hill Chalk Member of the Niobrara Chalk is a sedimentary deposit formed in the Western Interior Seaway of North America during the Late Cretaceous. In this study, I examined a unique fossiliferous bonebed from an uncertain horizon within the Smoky Hill Chalk in Gove County, Kansas, U.S.A. Over 40,450 taxonomically identifiable specimens were collected, where they consisted of at least four chondrichthyans, 24 osteichthyans, and two tetrapods, including taxa such as Nanocorax, Squalicorax, Rhinobatos, pycnodontids, Lepisosteidae, Protosphyraena, Pachyrhizodus, ichthyodectiforms, plethodids, Albulidae, Apateodus, Ichthyotringidae(?), cf. Stratodus, Cimolichthys, Enchodus, Acanthomorpha, Platecarpus, and Hesperornithiformes. The diversity of these vertebrates suggests the …

The Effects Of Repeat Concussive Injury On Hippocampal Neurogenesis In Rats, Duane Yu

College of Science and Health Theses and Dissertations

Abstract

A concussion is one of the most common types of traumatic brain injury. Repeat concussion has been associated with an increased likelihood of developing neurodegenerative diseases, such as Parkinson's and Alzheimer's Disease, and chronic traumatic encephalopathy. Although treatments are available to tolerate the symptoms, one potential treatment to address the pathology is to use adult neurogenesis to promote and recruit cells to injury sites for repair. Neurogenesis is the study of new neurons from neural stem cells (NSCs) present in adult humans at the hippocampal dentate gyrus. This study explored whether repeat concussion induces the proliferative capabilities of NSCs …

Physiological Effects Of Sustained Swimming On Salinity Acclimation In Chinook Salmon (Oncorhynchus Tshawytscha), Fritzman Geena

College of Science and Health Theses and Dissertations

Juvenile chinook salmon (Oncorhynchus tshawytscha) encounter a variety of environmental conditions on their migration from freshwater to the ocean. These migrations are physiologically demanding, requiring salmon to reverse their osmoregulatory strategies to successfully acclimate to changing salinity. This reversal occurs primarily at the gills (main osmoregulatory organ) where respiratory and osmoregulatory functions are occurring simultaneously. When subjected to a physiological stressor, the gills will compromise in design to alleviate the most limited function. This tradeoff is known as the ‘osmorespiratory compromise’. This thesis examined whether an osmorespiratory compromise in chinook salmon induced by sustained exercise (a gas exchange stressor) would …

The Impact Of Temperature On The Early Stages Of The Development Of The Body Axis In The Model Species Astyanax Mexicanus (Teleostei: Characidae), Sara Mohammad Alharbi

College of Science and Health Theses and Dissertations

Environmental fluctuations can change the phenotypic traits of ectotherms. Ectotherms such as fishes are very susceptible to changes in temperature. Recent studies on adults of the Mexican tetra, Astyanax mexicanus, indicate that variation in temperature during development significantly impacts vertebral number and body shape. Since vertebral number and somite number are related, I examined whether temperature significantly impacts somitogenesis and the early development of the body axis in this species. Fertilized eggs of the surface form of lab-reared Astyanax mexicanus were subjected to temperature treatments of 20°C, 24°C, and 28°C, and fixed hourly as they developed until they hatched. Embryos …

Songbird Use Of Problem-Solving Feeders In Urban And Rural Areas, Kayce Miller

College of Science and Health Theses and Dissertations

Behavioral flexibility is important for animals to adapt to novel situations in their environment. It has been suggested that birds living in complex environments (e.g., urban areas) should be more flexible than conspecifics in less complex environments. Birds are a particularly well studied group, where novel foraging problems are used to assess flexibility and problem-solving performance of urban and rural animals of the same species; however, this is most frequently done in a lab setting with wild-caught birds originating from different habitats. Using a field-based method to test problem-solving performance should give additional insight into other factors influencing birds’ flexibility. …

Developing A Transfection Method For Didymium Iridis, Uriel Adolfo Baray

College of Science and Health Theses and Dissertations

The plasmodial slime mold and member of Mycetozoa, Didymium iridis, has been studied in a variety of contexts such as RNA editing (Traphagen et al., 2010; Hendrickson and Silliker, 2010a; Hendrickson and Silliker, 2010b), mitochondrial inheritance (Silliker et al., 2002), biological speciation (Betterley and Collins, 1983; Clark et al., 1991) and mating competency (Shipley and Holt, 1982). Further studies are hindered by the lack of a transfection protocol, which would allow for gene manipulation in D. iridis (hereafter Didymium). Transfection methods developed in the related slime molds, Physarum polycephalum (Burland et al., 1993) and Dictyostelium discoideum (Fey et al., 1995; …

Zygote Gene Expression And Plasmodial Development In Didymium Iridis, Sean Schaefer

College of Science and Health Theses and Dissertations

Didymium iridis is a cosmopolitan species of plasmodial slime mold consisting of two distinct life stages. Haploid amoebae and diploid plasmodia feed on microscopic organisms such as bacteria and fungi through phagocytosis. Sexually compatible haploid amoebae act as gametes which when fused embark on an irreversible developmental change resulting in a diploid zygote. The zygote can undergo closed mitosis resulting in a multinucleated plasmodium. Little is known about changes in gene expression during this developmental transition. Our principal goal in this study was to provide a comprehensive list of genes likely to be involved in plasmodial development. We performed suppressive …

Comparative Brain Anatomy Of Lamniform Sharks (Elasmobranchii: Lamniformes) And Its Implications To Function, Behavioral Ecology, And Evolution, Francesco Guzzo

College of Science and Health Theses and Dissertations

Understanding the diversity of brain morphology is important to understand the evolution of cognitive ability and how ecology and phylogeny have influenced the variation in brain complexity. I examined the morphological variation of the brain in the shark order Lamniformes based on museum specimens and literature. Where I illustrate a wide range of morphological diversity in lamniform brains, my study shows that there is a strong positive correlation between brain size and body size that sharks with a larger brain tend to have a more foliated cerebellum, but that the body weight over brain weight did not correlate with cerebellar …

Integument-Based Inferences On The Swimming Ability And Prey Hunting Strategy Of The Bigeye Thresher Shark, Alopias Superciliosus (Lamniformes: Alopiidae), Joseph Aaron Frumkin

College of Science and Health Theses and Dissertations

Alopias is a group of lamniform sharks characterized by a highly elongate caudal fin with three known extant species: A. pelagicus (pelagic thresher shark), A. superciliosus (bigeye thresher shark), and A. vulpinus (common thresher shark). Alopias pelagicus and A. vulpinus are considered fast swimmers and use their caudal fin to hunt for small schooling fish by stunning them, but the feeding behavior has never been directly observed for A. superciliosus. Under the ecomorphological framework, I examined the following four integumentary variables of selected fast swimming (e.g., A. pelagicus, A. vulpinus, and Lamna) and slow swimming (e.g., Mitsukurina and Megachasma) lamniform …

A New Pachyrhizodontid Fish (Actinopterygii: Teleostei) From The Tarrant Formation (Cenomanian) Of The Upper Cretaceous Eagle Ford Group Of Texas, U.S.A., Maxwell G. London

College of Science and Health Theses and Dissertations

SMU 76938 is a fossil skeleton of a large, nearly complete actinopterygian bony fish housed in Southern Methodist University in Dallas, Texas, USA. It was collected from the Upper Cretaceous Tarrant Formation (middle Cenomanian; ~96 Ma) of the Eagle Ford Group in Tarrant County, Texas, an area where it was near the western margin of the East Texas Embayment during the Late Cretaceous. Although parts of the skull and dorsal fin are damaged, SMU 76938 is relatively complete, especially in the preservation of the caudal fin with its soft tissue outline. The fish has a fusiform body and measures about …

Modification Of Host Behavior And Transmission In The Acanthocephalan Acanthocephalus Dirus: Effects Of Development, Intraspecific Conflict, And Host Sex, Sara R. Teemer

College of Science and Health Theses and Dissertations

Parasites are organisms that live on or in another in order to survive. In some cases, parasites require more than one host to complete their life cycle and rely on a predation event for transmission to the next host. Inside the host, the parasite must access host resources to grow and develop from the non-infective to infective stages. At the infective stage, the parasite is able to survive within the definitive host. Development to this stage has been correlated with changes in antipredatory behaviors, body size and color, and reproduction of intermediate hosts in ways that may increase predation by …

Body Forms In Sharks (Chondrichthyes: Elasmobranchii), And Their Functional, Ecological, And Evolutionary Implications, Phillip C. Sternes

College of Science and Health Theses and Dissertations

Sharks are among the oldest vertebrate lineages in which their success has been attributed to their diversity in body shape and locomotor design. In this study, I investigated the diversity of body forms in extant sharks using landmark-based geometric morphometric analyses on lateral view illustrations of nearly all the known (ca. 470) extant sharks in a published guidebook. I ran three different analyses: the ‘full body,' ‘precaudal body,’ and ‘caudal fin' analyses. My study suggests that there are two basic body forms in sharks. The two major body forms are characterized as a ‘shallow-bodied’ form (Group A) and ‘deep-bodied’ form …

Wavelet Analysis Of Short Globular Homologous Proteins In Mesophile And Thermophile Prokaryotes, John B. Linehan

College of Science and Health Theses and Dissertations

This study looked to identify features related to thermal stability and function in the amino acid chains of short globular proteins from mesophile and thermophile species, within the constraint that the protein fold to perform a speci_c function. To do so 540 homologous pairs of proteins were studied. The amino acid chains were con-verted to hydrophobicity signals by assigning a hydropathy score to each residue in the polypeptide. The hydrophobicity signals were passed through a wavelet packet transform and the resulting spectra analyzed. Bootstrapping was used to gener-ate a control data set to determine if the true ordering of amino …

Phylogeography Of The Neotropical Fish Genus Rhoadsia (Teleostei: Characidae) In Ecuador, Roberto Valentino Cucalón Tamayo

College of Science and Health Theses and Dissertations

Western Ecuador is considered a biodiversity hotspot. Nevertheless, studies of population genetic structure and variation are rare, especially in aquatic species. The genus Rhoadsia is an endemic freshwater fish in this region with two recognized species, Rhoadsia minor and R. altipinna. Little is known about the evolutionary relationships of their populations, and due to morphological similarities, their validity as distinct species has been questioned. The present study uses a phylogeographic approach to examine the evolutionary history of the genus and the validity of the two described species. Furthermore, I investigated the possible geographical origin of the genus based on patterns …

Sex Differences In Behavioral Responses To Repeat Subconcussive Events, Rebecca J. Wilson

College of Science and Health Theses and Dissertations

Although concussions, especially those in athletes and military, have become a popular focus of neurotrauma research, subconcussions occur with higher frequency and are less well-studied. A subconcussion is loosely defined as an impact to the head that does not result in a diagnosable concussion but can result in neuronal alterations. Repeat subconcussions have been shown to produce behavioral impairments along with neuropathology that is similar to or worse than those seen in a single concussion injury. These studies have primarily included male subjects. Given the potential effects of hormones and NIH’s call for sex-inclusion in biomedical research, assessing female responses …

Lcp1 Mutant Zebrafish: A Look At Neutrophils, Cancer, And Gene Compensation, Taylor Mitchell

College of Science and Health Theses and Dissertations

Lymphocyte cytosolic protein 1 (lcp1 or L-plastin) is a small actin-bundling protein that is typically only expressed in motile leukocytes, such as neutrophils and macrophages. However, it is also overexpressed in cancer cells, which may be related to tumor metastasis. Using CRISPR/Cas9 gene editing, our lab has created zebrafish that are genetic knockouts for lcp1 in order to better understand the relationship between L-plastin and cell motility.

Previous studies on L-plastin knockout mice have shown that the mutants have a decreased immune response, and therefore I predicted that our zebrafish mutants might have impaired development or distribution of immune cells. …