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Analysis Of Developmental Cardiogenic Processes Mediated By Fox And Zinc-Finger Transcription Factors, Rajnandani Katariya

All-Inclusive List of Electronic Theses and Dissertations

Cardiogenesis is a highly choreographed biological process requiring the precise integration of gene regulatory networks to govern cell division, fate determination, and spatial positioning. Disruptions in these mechanisms lead to congenital heart defects (CHDs), which affect approximately 1% of live births globally. Due to the evolutionary conservation of cardiac signaling pathways and the structural homologies between the Drosophila dorsal vessel and the early vertebrate heart tube, Drosophila melanogaster serves as a powerful model for dissecting the fundamental mechanisms of heart development. This dissertation investigates the molecular orchestration of cardiac development, specifically focusing on the roles of the transcription factors Jumu …

Foraging Plasticity And Mercury Contamination In Red-Legged Kittiwakes: A Multiple Stressor Perspective, Sam E. Clay

All-Inclusive List of Electronic Theses and Dissertations

Arctic seabirds are facing increasing stress from climate change, yet the interactive effects of multiple stressors on behavior remain poorly understood. Adopting a multiple stressor perspective promises to advance understanding of avian behavioral responses to climate change, as climate change is exposing Arctic and subarctic animals to a complex set of stressors rather than a single stressor in isolation. Using the red-legged kittiwake (Rissa brevirostris) as a model, I examined how multiple stressors, including mercury (Hg) exposure, shifting wind conditions, and varying foraging conditions linked to sea surface temperature (SST) may interact to constrain behavioral plasticity and energetically expensive behavior …

Reconstruction Of Fox Transcription Factor-Regulated Subnetworks Mediating Cardiac Progenitor Cell Divisions, Md Rezaul Hasan

All-Inclusive List of Electronic Theses and Dissertations

Congenital heart disease (CHD) is the most common congenital anomaly worldwide, affecting approximately 1% of live births, corresponding to 1.35 million infants born with CHD each year, and remains a leading cause of infant mortality; therefore, it is urgent to understand the genetic and molecular mechanisms underlying CHD for advancing early diagnosis and treatment. Because many aspects of the Drosophila heart formation are highly reminiscent of vertebrate heart development, Drosophila melanogaster serves as a simple yet powerful model system for studying cardiac development and CHD. While at least eight Forkhead box (Fox) transcription factors (TFs) are required for proper cardiac …

Dendroclimatic Response Of The Wet Miombo Woodland Species: A Case Study Of Mufulira District, Copperbelt Province, Zambia, Collins Chibuye Malubeni

All-Inclusive List of Electronic Theses and Dissertations

Zambia is a tropical, landlocked country that lies in the South-Central part of Africa. The climate in Zambia includes distinct dry and rainy seasons, mainly influenced by the north-south movement of the Intertropical Convergence Zone (ITCZ), which shifts seasonally. This research is focused on understanding the relationship between tree growth and climate using dendrochronology. Forty-nine tropical species, including Julbernardia paniculata, Brachystegia longifolia, and Pericopsis angolensis, were analysed for dendroclimatic potential, and 70% showed clear ring formation, indicating that trees in this locality produce distinct annual ring boundaries. For the single species chronology, thirteen cores from eight trees that were initially …

Microplastic Composition And Exposure Pathways In Freshwater Systems: A Multi-Matrix Comparison Between Streams And Retention Ponds In Hamilton County, In, Mya Whaley

All-Inclusive List of Electronic Theses and Dissertations

Since the early 1900s, the use of plastics has increased exponentially. The breakdown of plastic materials has exposed all ecosystems to microplastics (small particles of plastic < 5 mm), which are now ubiquitous in natural settings. Microplastics have a relatively large surface area, and many chemicals adsorb to these small particles, impacting their fate and transport of pollution. While microplastics have been found in virtually every setting on Earth, research is necessary to understand their impact on freshwater ecosystems and biogeochemical cycles. The focus of this research was to investigate microplastic compositions in crayfish, sediments, and water samples collected in streams and retention ponds. We analyzed trends in microplastic counts across different land-cover classes, waterbody types, and species, and compared concentrations among matrices to improve our understanding of microplastic exposure pathways in freshwater ecosystems. As a secondary objective, lead and arsenic concentrations were analyzed from sediment samples to investigate metal burdens and compare them to microplastic concentrations. Our findings revealed that, in general, urban streams had the highest microplastic concentrations within land cover categories, and retention ponds had higher microplastic counts than streams. Crayfish, such as F. rusticus had higher microplastic concentrations than F. virilis and F. propinquus, although these results may be influenced by study design. The most common microplastic type was fibers, and most common color was transparent. There was no significant correlation between microplastic and metal concentrations in sediments. We found crayfish to be adequate bioindicators of microplastic pollution, because they were less impacted by environmental variability than sediment and water samples. This research presents the first evidence of microplastics in our study species, F. propinquus, F. rusticus, and F. virlis. This work presents new evidence of microplastic accumulation in crayfish, sediments, and water from freshwater systems in the Midwestern United States. Microplastics were found in every sample type—crayfish, water, and sediment—across urban, rural, and forested landscapes, highlighting their pervasive distribution. The findings provide foundational data for assessing emerging ecological and human-health risks and emphasize the importance of sustained monitoring and research on MP contamination in freshwater environments.

The Role Of Floodplain Connectivity In Shaping The Abundance, Size-Class Distribution, And Schooling Behavior Of The Associated Fish Assemblage, Adam H. Quade

LSU New Orleans Theses and Dissertations

The life histories of many Louisiana fishes are closely tied to the timing, magnitude, and duration of the Mississippi River flood pulse, which regulates the ecological connectivity and productivity of adjacent floodplain habitats. Anthropogenic modifications such as levee construction and water-control structures have disrupted these natural hydrologic linkages, altering habitat quality and community structure across the Lower Mississippi River Basin. This dissertation used high-resolution imaging sonar to investigate how fish assemblages, species, and collectives respond to changes in floodplain connectivity within the Richard K. Yancey Wildlife Management Area prior to hydrologic restoration. In the first chapter, I applied imaging sonar …

The Undergraduate Education And Scientific Literacy: Exploring How College Influences Student Perception Of Covid-19 Events, Peyton Brooking

Theses/Capstones/Creative Projects

Current undergraduate students received much of their education following the events of the COVID-19 pandemic. Many of these students experienced pandemic events before receiving any or most of their science-based higher education. Exploring their progress through higher education, and how it retroactively influenced their perception of pandemic events, serves as an informative research area. This study explores how undergraduate education in the sciences influences student engagement with complex recent events in science. In addition, this study asked how higher education builds confidence in interpreting this information. Additionally, students were surveyed to understand their scientific literacy baseline at the beginning of …

Analysis Of The Effects Of Astaxanthin On Human Colorectal Cancer Cells, Kara A. Walters

Theses/Capstones/Creative Projects

Astaxanthin (AXT) is an antioxidant carotenoid that is produced by the microalgae Haemococcus pluvialis. This supplement is best known for its potential health benefits including anti-inflammatory, antitumor, immunomodulatory, anticancer and antidiabetic activities. Astaxanthin is marketed as an oral dietary supplement and is widely used in the nutraceutical industry as well as a coloring agent in the food industry. Since Astaxanthin has been increasingly popular as a dietary supplement, cytotoxicity is relevant to consumer exposure. Obtaining the IC50, the concentration that inhibits 50% of cell growth, is important to find how Astaxanthin may interact with cancer, and this can be found …

The Beat Behind The Bark: Investigating The Effects Of Music Tempo On Canine Physiological And Psychological States, Marley Lanier

Poster Presentations

Music is a universal component of human culture that has been demonstrated influencing emotional, cognitive, and physiological responses, specifically heart rate and hormonal responses (Mehr et al., 2019; Trappe, 2012). Recently, this research has expended to explore how music may affect non-human animals, particularly dogs, due to their roles as therapy animals, service animals, and human companions (Lindig et al., 2020; Gee et al., 2021). Being able to understand how music influences canine stress and relaxation hold important applications in environments such as shelters, veterinary clinics, and at home. One important feature of music is tempo, or beats per minute …

Evaluating Fungal Endophytes Inoculation As A Mechanism For Salt Tolerance In Juncus Roemarianus, Rani Badve

Honors Theses

Salinity stress is increasing in coastal and estuarine ecosystems due to increasing temperatures and the reduction of freshwater inputs via precipitation pattern changes. Elevated salinity can negatively affect plant survival, threatening the stability of coastal wetlands and the ecosystem services they provide. Juncus roemerianus is a common and dominant marsh plant in the Northern Gulf Coast that lives in varying salinities. Growing evidence suggests that root-associated fungal endophytes may contribute to enhanced stress tolerance; however, the response of fungal communities to salinity remains poorly understood.

This study evaluated how salinity influences the abundance and diversity of culturable root-associated fungal communities …

Acute Effects Of The Psychoactive Pollutant Fluoxetine On The Antipredator Behavior Of The Gulf Killifish (Fundulus Grandis), Semyra Reus

Honors Theses

Pharmaceutical contaminants are increasingly prevalent in aquatic environments, yet their sublethal effects on ecologically relevant behaviors remain poorly understood, particularly in estuarine systems. Selective serotonin reuptake inhibitors (SSRIs), such as fluoxetine, are of particular concern due to the conserved role of serotonin in regulating behavior across vertebrates. Here, we investigated how acute exposure to environmentally relevant concentrations of fluoxetine influences anti-predator behavior in Gulf killifish (Fundulus grandis), a key estuarine fish commonly found in saltmarsh habitats. Killifish were exposed to control (0 ng/L), low (17.8 ng/L), and high (596 ng/L) fluoxetine concentrations and subsequently tested in the presence …

Urea-Based Boronium Salts As Antimicrobial Agents, Gabriel Allen Merchant

Honors Theses

Quaternary ammonium compounds (QACs) are widely used in disinfectants due to their ability to inhibit the growth of and eliminate microbes. The potency, broad-spectrum activity, and low cost of QACs have made them a cornerstone of modem hygiene. In recent years, QACs have garnered many health and safety concerns due to their overuse and subsequent accumulation in the environment. The increased use of QACs has further led to an increase in antimicrobial-resistant bacteria, making the synthesis of novel antibacterial compounds vital to combat this growing threat. Recent advances in boronium salts offer a unique alternative to address these adverse effects. …

Spectral Characterization Of Colorectal Cancer Using Excitation-Scanning Hyperspectral Imaging, Natalie Hadad

Honors Theses

Colorectal cancer is one of the most common and deadly cancers worldwide, with a lifetime risk of approximately one in twenty-three for men and one in twenty-five for women. Although early detection significantly improves survival, current diagnostic approaches such as tissue biopsy are invasive, reliant on subjective interpretation, have extended turnaround times, and risk missing flat or depressed lesions that are more difficult to detect than raised polyps. These limitations highlight the need for objective, minimally invasive technologies capable of detecting early tissue changes. This study investigates excitation-scanning hyperspectral imaging (Ex-HSI) as a label-free optical approach for identifying colorectal cancer–associated …

Novel Biomarker Discovery In Multiple Sclerosis, Manisha Gangasani

Honors Theses

Multiple Sclerosis (MS) is a chronic neuroinflammatory disorder affecting the brain, spinal cord, and optic nerve. Patients experience cognitive, motor, autonomic, and emotional symptoms that often overlap with other neurological conditions, making early diagnosis challenging. Current diagnostic criteria require evidence of lesions with dissemination in time and space. Racial disparities in MS outcomes are well documented, with Black individuals often exhibiting greater disease severity, higher relapse rates, and increased disability compared to White individuals. These differences likely reflect a combination of genetic, biological, environmental, and healthcare access factors, underscoring the need to improve early diagnosis and reduce inequities in care. …

Developing A Protocol For Non-Cellular Transplantation Of Donor Mitochondria Into Recipient Cells, Andrew Parton

Honors Theses

Tumor innervation has emerged as a critical feature of cancer progression, with increased nerve density correlating with enhanced aggressiveness, metastatic dissemination, and poor clinical outcome. However, the functional contribution of neurons to tumor biology remains incompletely defined. We recently identified the intercellular transfer of mitochondria from neurons to cancer cells as a mechanism that promotes tumor progression. We therefore hypothesized that disruption of this transfer could attenuate tumor aggressivity. To directly investigate this process, we developed an approach to isolate mitochondria from donor cells and transplant them into recipient cancer cells independently of canonical cell-cell interactions. Transferred mitochondria were tracked …

Discerning Patterns Of Floral Sugar-Feeding: Dynamics Of The Mosquito Culex Antillummagnorum In Puerto Rico, Ella J. Branham

Master's Theses

Mosquitoes rely on sugar feeding for survival, primarily from flowering plants, yet mosquito–plant interactions remain understudied. I examined plant-feeding associations of the mosquito Culex antillummagnorum in the Luquillo Experimental Forest of Puerto Rico, which may clarify patterns of habitat use, disease dynamics, and broader species interactions. First, plant DNA was extracted from field-collected Cx. antillummagnorum to identify potential nectar sources. DNA barcoding produced positive matches to the flowering plant genera Billia, Aesculus, Cladium, Fimbristylis, Xyris, Cakile, and Habenaria. Habenaria was the most compelling result because it belongs to the same subtribe of orchids …

Redeveloping Mississippi: A Case Study On Brownfields In Central & Southern Mississippi, Sahrah R. Yeroozedek

Master's Theses

Brownfields, or properties that are or possibly are contaminated with dangerous materials, represent a common obstacle for communities in Mississippi. The real or potential presence of contaminants at these sites often deters investors due to costly cleanup requirements (EPA, n.d. -b). The Environmental Protection Agency (EPA), through its Brownfield Revitalization Program, implemented guidelines for covering the costs and labor associated with the remediation of these properties. The EPA is not, however, responsible for redevelopment that supports long-term environmental and economic sustainability. Although the EPA maintains inventories of all Brownfields, there is also no comprehensive database of Brownfields and their current …

Exploring A 'Fishy' Solution: Uncovering Human Norovirus Using A Zebrafish Model, Sahaana Chandran

Graduate Theses and Dissertations

Human norovirus (HuNoV) is the leading cause of acute gastroenteritis worldwide; however, the lack of robust laboratory culture systems and reliable animal models has limited progress in understanding viral replication and developing effective intervention strategies. While alternative models such as the zebrafish system have been explored, gaps remain in evaluating their ability to support replication across diverse HuNoV strains and in identifying factors that influence infectivity. This dissertation provides a comprehensive investigation into the use of the zebrafish model for studying viral replication, host interactions, and potential inhibition strategies. Initial studies focused on optimizing viral delivery methods using Tulane virus …

Leveraging Historic Collections: Investigating Morphometric Differentiation In Members Of The Arisaema Triphyllum (L.) Schott (Araceae) Species Complex, Morgan Bradley Russell

Graduate Theses and Dissertations

The Jack-in-the-pulpit (Arisaema triphyllum (L.) Schott) is an herbaceous perennial herb of North America, and its taxonomic history is full of confusion and rank shifts. Now split into six species, the A. triphyllum species complex consists of morphologically similar taxa that have differing ploidy levels. In Chapter I, I compiled a detailed introduction and history for these taxa, focusing on their taxonomic complexity and morphological ambiguity in herbarium specimens and immature plants. I also presented their ploidy distinctions and how the implications of polyploidy may hold answers to parsing them apart, especially in dried herbarium specimens where defining characteristics are …

Bats And Bacteria: Infection Dynamics At The Human-Wildlife Interface, Isabella Katherine Deanglis

Graduate Theses and Dissertations

As the second most diverse mammalian order, bats host an array of pathogens, some of which are known to infect humans. Synanthropic bats share spaces with humans, resulting in bat-borne pathogen exposure. While most bat-borne disease research has focused on viral pathogens, bats host numerous bacterial pathogens with zoonotic potential. By integrating a global meta-analysis with field studies in Sub-Saharan Africa, I characterize the structural attributes that facilitate shared interfaces, the bacterial pathogens present in synanthropic bats of rural Kenya, and the physiological and environmental dynamics influencing odds of infection in these synanthropic bats. Finally, I evaluate the clinical relevance …

Dissecting The Complex Genomic Landscape Underlying Oxidative Stress Resistance Using Natural Variation In Yeast, Sonali Lakshika Anne Lenaduwe

Graduate Theses and Dissertations

Stress is experienced across the tree of life. Survival in fluctuating environments depends on a robust genetic architecture. This dissertation examines the genetic and metabolic determinants underlying one such adaptive response: cross-protection. Leveraging natural variation in the stress responses of budding yeast, Saccharomyces cerevisiae, I examine the genetic variation contributing to ethanol-induced cross-protection against oxidative stress. Acquired stress resistance, in which mild pre-exposure improves survival to subsequent stresses, is prevalent across diverse organisms and can involve both same-stress and cross-protection. Using high-throughput bulk segregant analysis (BSA-seq) and advanced intercross mapping populations derived from natural yeast isolates, I identify quantitative trait …

Understanding Tlr3 Immune Response Activation In Cryptosporidium Parvum And Cryspovirus Pathogenesis, Surayya Hudayberganova

Biochemistry and Molecular Biology

Cryptosporidiosis is a serious gastrointestinal illness caused by a protozoan parasite known as Cryptosporidium. It is particularly dangerous for malnourished children and those with compromised immune systems. My research focuses on the Toll-like receptor 3 (TLR3) response to the Cryptosporidium parvum infection, specifically in the presence of the parasite’s viral mutualist named cryspovirus (CSpV1). Results using research methodologies like ELISA and RT-qPCR have indicated that TLR3 expression increases during the infection process of Cryptosporidium parvum (C. parvum). Furthermore, one intriguing observation concluded during this study suggests that administering the TLR3-specific inhibitor CU-CPT4a to infected cells drastically decreased this activation. This …

Unveiling Factors Influencing Extract Yield From Milled Rice In Brewing, Matthew Aitkens

Graduate Theses and Dissertations

Rice (Oryza sativa L.) presents a locally sourced, climate-resistant starch source for the brewing industry. As barley faces increased uncertainty due to rising temperatures, Arkansas-grown rice offers a more stable and cost-effective alternative starch source. However, the use of milled adjunct rice by brewers has remained limited, largely due to knowledge gaps about cultivar-specific properties relative to brewing. Chapter 1 provides an overview of rice as a brewing adjunct, reviewing the physiochemical properties important to brewing success. These properties include kernel size, kernel breakage, amylose content, and gelatinization temperature. Mashing strategies for multiple different brewing layouts are overviewed, showing practical …

Revised - The Role Of Gad67/65 In The Therapeutic Effects Of Ketamine And Fluoxetine In Fear-Conditioned Mice, Alex G. Ottimer

All NMU Master's Theses

Post-traumatic stress disorder (PTSD) is a chronic psychiatric disorder and the most common disorder following exposure to a traumatic event. The most commonly used drugs in PTSD treatment are selective serotonin reuptake inhibitors (SSRIs), though only about 50% of patients respond to this treatment. Previous work in our lab demonstrated the combination of chronic fluoxetine (FLX) and acute ketamine treatment decreased fear response in a contextual fear paradigm in male C57/BL mice. In rodents, fear conditioning (FC) is commonly used in the literature to induce behaviors related to PTSD. The mammalian central fear memory circuit involves a dynamic interplay between …

Recruitment Of Chrysaora Chesapeakei On Floating Docks Versus Bulkhead Surfaces: Which Axis Is Foulset?, Alyssa Lamberto

Theses, Dissertations and Culminating Projects

Blooms of Chrysaora chesapeakei (bay nettles) have increased sharply in Barnegat Bay, New Jersey, reducing both ecological integrity and economic value. Because population expansion is driven primarily by the benthic polyp stage, where individuals attach to hard substrates and reproduce asexually, effective management must target the surfaces where polyps settle and clone themselves. The rapid growth of artificial infrastructure, particularly vinyl docks and bulkheads, has expanded available habitat for polyp recruitment. Scrubbing these structures has been shown to reduce ephyrae production, but it remains unclear whether both docks and bulkheads warrant equal management attention. This study compared recruitment on horizontal …

Individual Recognition: Do Horned Passalus, Odontotaenius Disjunctus, Display Individual Discrimination Of Familiar And Unfamiliar Conspecifics Through Changes In Their Behavior?, Sabrina Galloza

Theses, Dissertations and Culminating Projects

The horned passalus, Odontotaenius disjunctus, are subsocial beetles that inhabit and defend decaying wood where they create galleries to live, mate, breed and provide brood care. The species is well known for their stridulations, making up to 14 different sounds, having one of the greatest repertoire of sounds for any known arthropod. Typically living in family units, it has been found that several families can inhabit the same log, therefore, the horned passalus can come into contact with both kin and non-kin. It is currently unknown whether the horned passalus can distinguish between nestmates and non-nestmates. Additionally, it is unknown …

Antimicrobial Activity Of Sulbactam-Durlobactam Against Acinetobacter Baumannii-Calcoaceticus Complex Strains Causing Non-Respiratory And Non-Bloodstream Infections From The United States (2023–2025), Erik Munson

Clinical Lab Sciences Faculty Research and Publications

Acinetobacter baumannii most often causes pneumonia in critically ill patients. However, A. baumannii is also an important cause of a broader range of infections, including skin/wound and urinary tract infections. This study aims to evaluate the in vitro activity of sulbactam-durlobactam and comparator antibiotics, including meropenem and cefiderocol against A. baumannii-calcoaceticus complex isolates from non-respiratory and non-bloodstream sources. Samples included 285 A. baumannii-calcoaceticus complex isolates enriched for carbapenem resistance collected across 17 states in the United States (January 2023–May 2025). Antimicrobial susceptibility tests were conducted by manual broth microdilution and interpreted according to Clinical and Laboratory Standards Institute (CLSI) and …

College Of Natural Sciences Spring Newsletter, College Of Natural Sciences

College of Natural Sciences Newsletters and Reports

[Page 1] Dean's Message
[Page] 2 Awards & Recognitions // Student Spotlights
[Page] 3 Zhang Named to Landsat Science Team // The Power of Teaching
[Page] 4 “Science as Art” Competition Welcomes High School Artists
[Page] 5 Testing for “Forever Chemicals” in Surface Water // New Faculty Spotlight
[Page] 6 Ambassador Initiated Outreach
[Page] 7 57th Annual Geography Convention
[Page] 8 Twice the Impact on On Call with the Prairie Doc
[Page] 9 Making Staple Foods Healthier // Halaweish & Cole-Dai Retire
[Page] 10 Drone Day 2026
[Page] 11 Student Research, Scholarship, and Creative Activity Day (SRSCAD)
[Page] 12 Ceremony …

Morphological Variation Of Lingual Glands In Wild American Alligator (Alligator Mississippiensis) Populations, Benjamin Angalet

Master's Theses

American alligators (Alligator mississippiensis) inhabit diverse aquatic ecosystems including freshwater wetlands, swamps, and estuarine rivers. As apex predators, their physiological resilience has implications for ecosystem stability and long-term conservation. With projected sea-level rise and increasing saltwater intrusion into coastal freshwater habitats, understanding the osmoregulatory capacity of alligators is increasingly important. Unlike marine-tolerant crocodilians such as the saltwater crocodile (Crocodylus porosus), which possess specialized salt-secreting lingual glands in addition to renal and cloacal mechanisms, the morphology and physiological significance of lingual glands in wild American alligators remain poorly understood. This study examined lingual gland morphology and plasma …

Preliminary Vascular Plant Checklist Of The City Of Chattanooga, Matthew J. Scott

Honors Theses

The City of Chattanooga, Tennessee was designated as a National Park City in April 2025 by the National Park City Foundation. Yet, there has not been a comprehensive vascular flora compiled for the city, though there have been extensive collections and observations made of the plant biodiversity in the area from the late 1800s onward. The goal of this project was to examine both the existing herbarium collections and public observation records from iNaturalist to compile a preliminary vascular plant checklist for Chattanooga, and to include conservation and ecological data for the species currently documented to provide a holistic review …