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Effects Of Tourist Feeding On The Gut Microbiome And Ecophysiology Of Endangered Northern Bahamian Rock Iguana (Cyclura Cychlura), Erin Lucy Lewis

All Graduate Theses and Dissertations, Fall 2023 to Present

The lifespan and reproduction of an animal depends on maintaining a healthy physiology. The proportion of individuals that survive to an age at which procreation can occur is important to long-term stability of populations and contributes to species survival. Health in an animal is measured in a variety of ways, including through monitoring of the body’s physiological systems, as well as its ability to respond to invading pathogens, and through the different types of bacteria present in the gut. Relationships among those different health metrics have been discovered in recent years and have been found to play important roles in …

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 …

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 …

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 …

From Prairie To Practice: Forensic Taphonomy, Ethics, And Regional Ecology In Southeastern Nebraska, Jessica F. L. Gammage

Department of Anthropology: Theses and Student Research

Forensic taphonomy examines the postmortem processes that affect human remains within specific environmental contexts and plays a critical role in medicolegal death investigation. Despite significant advances in decomposition research, experimental studies remain geographically and environmentally uneven, limiting the transferability of postmortem interval (PMI) estimation methods across regions. The Central Great Plains are underrepresented in forensic taphonomic research despite its distinct ecological and geomorphological characteristics.

This thesis evaluates southeastern Nebraska as a specific regional setting for forensic taphonomic research by integrating ecological, pedological, and geomorphological data with current forensic literature. Tallgrass prairie vegetation, loess-derived soils, seasonal moisture variability, and dynamic fluvial …

Understanding Roma Oppression In Europe Through Humantarian Forensic Analysis, Christal L. Quinn

Department of Anthropology: Theses and Student Research

This thesis examines the marginalization of Roma people in Europe, and how humanitarian forensic practices may help Roma communities in their quest for justice and recognition. The study draws exclusively on secondary information to examine the social, political, and legal issues affecting the Roma communities, who have endured centuries of institutional discrimination, marginalization, and violence. This thesis identifies ways in which systematic oppression continues to limit Roma communities’ access to education, housing, healthcare, and legal protection through a review of relevant literature and applicable theoretical frameworks. The study also examines the relevance of forensic science, particularly its humanitarian applications, in …

Non-Destructive Automated Classification Of Human And Large Mammal Long Bone Fragments: A Deep Learning Approach Using Micro-Ct Histomorphology And Grad-Cam Interpretation, Kathleen Marie Kelley

Department of Anthropology: Theses and Student Research

This study explores the development and validation of an automated, deep learning system designed to differentiate human from large mammal long bone fragments using micro-CT imagery. A comprehensive dataset of cross-sectional µCT images was assembled from human and animal skeletal material processed at the DPAA, Nebraska. A convolutional neural network (CNN) based on a ResNet-18 architecture, utilizing transfer learning from ImageNet weights, was trained to classify µCT images as human or animal. The model achieved a mean classification accuracy of 89.85% (± 8.27%) across five sample-level cross-validation folds, with a sensitivity of 96.21% and a 95% bootstrap confidence interval of …

Effects Of Vitamin E Deficiency On Anxiety-Like Behavior In Zebrafish With Distinct Stress Coping Styles, Areem Zahid

Theses/Capstones/Creative Projects

Stress and anxiety disorders affect millions worldwide and represent a significant public health burden. Individual differences in stress coping style and antioxidant regulation contribute to variability in stress responsiveness and anxiety-related behaviors. Oxidative imbalance has been implicated in the neurobiology of anxiety, but its interaction with inherent stress coping phenotypes remains unclear. This study examined whether long-term dietary vitamin E deficiency alters anxiety-like behaviors in zebrafish selectively bred for proactive and reactive stress coping styles. Adult zebrafish were maintained on either a vitamin E–sufficient or vitamin E–deficient diet for five months, followed by behavioral assessment using the novel tank diving …

Cancer Gets Extreme: How Extremophiles Can Improve Research And Therapy, Jason Malmgren

Celebrating Scholarship and Creativity Day (2018-)

Extremophiles are organisms that can survive in extreme environmental conditions, and their unique biological adaptations have gained attention for potential applications in cancer research. This paper explores how the molecular characteristics of extremophiles, such as enhanced DNA repair, resistance to oxidative stress, and structural stability, may be useful in improving cancer treatment strategies. A range of studies were examined to understand both direct and indirect roles of extremophile-derived compounds in oncology. Some research shows that compounds from organisms like Deinococcus radiodurans and extremophilic Streptomyces species can inhibit cancer cell growth, increase reactive oxygen species, and trigger apoptosis. Other studies highlight …

Cytoplasmic Shift Of Interferon Regulatory Factors Co‐Evolved With Jawed Vertebrate Innate Immunity, Vanessa M. Hubing

Honors Program: Senior Projects (Public)

The emergence of jaws in early vertebrates introduced a novel feeding apparatus and powerful oral defenses, but it also increased the risk of physical injury and pathogen exposure. Interferon regulatory factors (IRFs) play critical roles in orches-trating innate immunity and inflammation in response to invading microbes and tissue damage, with their subcellular local-ization being essential to some IRFs' function. Our results indicate that IRF members underwent independent expansion and diversification in two distinct vertebrate lineages: jawed and jawless vertebrates. The jawed vertebrate-specific factor, IRF5, has maintained conserved nuclear export sequences throughout evolution, while newly diversified IRF members in jawed verte-brates …

Exploring Student Sensemaking During A Collaborative Biology Lab, Rebecca Kollipara

School of Natural Resources: Dissertations, Theses, and Student Research

Collaborative learning environments offer valuable opportunities for students to construct scientific understanding through dialogue, yet the conditions that support sustained conceptual reasoning in group settings remain incompletely understood. While prior research has identified discourse moves associated with productive collaboration, less attention has been paid to how those moves function together across turns and conceptual boundaries, or how individual student characteristics shape their emergence. This thesis examines collaborative sensemaking in an undergraduate General Biology II course, drawing on two complementary analyses of student discourse during a bryophyte life-cycle modeling activity.

Chapter 1 investigates how student groups participated in sensemaking and how …

Biohybrid Robotic Jellyfish For Swimming-Enhanced Vertical Ocean Profiling, Kelsi M. Rutledge, Sean Colin, John H. Costello, Noa Yoder, Simon R. Anuszczyk, Kelly R. Sutherland, Brad L. Gemmell, John O. Dabiri

Arts & Sciences Faculty Publications

Ocean monitoring is essential for understanding climate change and marine ecosystem dynamics, yet achieving comprehensive global coverage remains a challenge in oceanography. Current technologies face limitations in cost, power, hardware, and depth capacity that restrict widespread monitoring capabilities. Here we show that biohybrid robotic jellyfish (Aurelia aurita) can serve as autonomous vertical ocean profilers by integrating microcontrollers with positively buoyant sensor payloads, achieving controlled vertical-profiling capabilities. Laboratory experiments demonstrated repeatable up–down trajectories, quantified force balance limits, and identified predictable, size-dependent descent swimming speeds. Field deployments in Massachusetts coastal waters and the open ocean off the Florida Keys demonstrated field operation …

The Effect Of Drought On Avian Migratory Patterns And Stopover Through Texas And Louisiana, Ian Becker

Theses and Dissertations

Extreme weather events pose a massive threat for native ecosystems. As precipitation and temperature patterns are altered due to climate change, drought may become an incredibly severe event on the landscape. Drought directly impacts resources that migratory birds need during stopover en route to breeding and non-breeding grounds. Here, I quantify the impacts of drought on migration through Texas and Louisiana using 26 years of weather surveillance radar data. To understand how drought interacts with the local environment to impact migration, I tested 4 hypotheses displaying drought’s ability to impact migrants in conjunction with climatic and habitat level characteristics. Fall …

Developing A Qpcr Method For Evaluating Parasitoid Wasps As A Potential Means Of Control Of The Southern Cattle Fever Tick Rhipicephalus (Boophilus) Microplus In South Texas, Abbey Abalos

Theses and Dissertations

Ixodiphagus spp. wasps are natural enemies of ticks that have been reported to cause mortality in multiple tick species. Parasitoid wasps may represent a potential biocontrol alternative to traditional chemical tick control methods, which are challenged by non-target toxicity and the development of pesticide resistance in species of concern such as Rhipicephalus microplus, a pest of livestock that causes billions of dollars in loss to the livestock industry worldwide. Rhipicephalus sanguineus s.l. is a congeneric species of R. microplus, and parasitism of R. sanguineus by Ixodiphagus sp. in areas of co-occurrence has been observed. It is unknown if R. microplus …

The Impact Of Nutrition On Insecticide Resistance And Gene Expression In Aedes Aegypti, Esmeralda Guadalupe Rosas

Theses and Dissertations

The development of insecticide resistance in Aedes aegypti, a major vector of dengue and Zika viruses, threatens vector control efforts, particularly in endemic regions such as South Texas. Insecticides remain widely used; however, their overuse has accelerated metabolic resistance mediated by cytochrome P450 enzymes. Environmental factors such as larval nutrition may influence mosquito physiology and resistance-associated gene expression, yet this relationship remains poorly understood. This study examines how larval nutritional conditions affect the expression of cytochrome P450 genes linked to pyrethroid resistance in Aedes aegypti. Larvae were reared under five dietary treatments differing in lipid and protein ratios, and adults …

Resource Allocation Trade-Offs Between Longevity And Reproduction In Daphnia Magna, Amelia Pearson

Electronic Theses and Dissertations

Although trade-offs between longevity and reproduction have been described for a long time, the genetic mechanisms by which organisms modulate allocation of resources between these two essential processes remain poorly understood, due to their complex nature and their modification by existing nutritional states and environmental cues. Daphnia magna represents a valuable model for investigation in this area due to their moderate lifespan and cyclic parthenogenetic mode of reproduction, allowing for the easy study of gene by environment interactions. This dissertation first investigates the change in mortality, reproduction, activity, and gene expression when fully fed Daphnia and calorically restricted Daphnia are …

Volume 17, Christian O’Neill, Kyara Greene, Savva Sidorov, Laura Bisaillon, Luke Clemmer, Hannah Gordon, Kitt Benson, Taylor Blount, Rachel Danzitz, Nicholas Duellman, Chase Gionis, Hima Fernando, Seth Franzyshen, Onyx Gonzalez, Bryan Lin, Samantha Start, Ysabel Wells, Maggie Duncan

Incite: The Journal of Undergraduate Scholarship

Introduction Dr. Amorette Barber, Director, Office of Student Research

From the Editor Dr. Hannah Dudley-Shotwell

Cover Artist’s Statement Maggie Duncan

On Mentoring Dr. Yulia Uryadova

Ukrainian Resistance in the Face of Russification: Nestor Makhno and Anarchism

by Christian O’Neill

Life Vest by Kyara Greene

Isolation and 16S rRNA Identification of Bacteria from Fire Department Connection Pipe by Savva Sidorov

The Effectiveness of Planned Exercise in Reducing ADHD Symptoms in Children by Laura Bisaillon & Luke Clemmer

Linguistic Analysis on Confidence and Communication Strategies with Disparities Between Sign Fluency and Hearing Impairment by Hannah Gordon

Freedmen in Indian Territory by Kitt …

From Antigen Presentation To Tumor Control: Mechanisms Of Type I Conventional Dendritic Cell-Based Cancer Vaccines, Josue E. Pineda

Dissertations and Theses (Open Access)

Type 1 conventional dendritic cells (cDC1s) are important for generating and sustaining antitumor immunity. Accordingly, the abundance of cDC1s in human tumors correlates with improved outcomes in cancer. Capitalizing on this role, we previously demonstrated that vaccination with in vitro-derived murine cDC1s elicits durable tumor control in multiple preclinical models; however, the immunological mechanisms underlying the efficacy of cDC1 vaccination remain unclear. Here, we examined whether in vitro-derived cDC1s resemble tumor-infiltrating DC populations and whether MHC-I and MHC-II antigen presentation contribute to cDC1-mediated tumor control following vaccination in melanoma.

As expected, MHC-I- or MHC-II-deficiency had minimal impact on …

Enhancing Walleye (Ogaa) Recruitment: Evaluating Assisted Reproduction As A Mitigation Strategy, Douglass Keiser

Biology Graduate Theses

Over the past several decades, cold- and cool-water fish populations across the Upper Midwest, including Minnesota and Wisconsin, have shown troubling signs of decline. Among the most affected is the walleye/Ogaa (Sander vitreus), a species deeply embedded in the ecological balance, cultural identity, and economic vitality of the region, and central to the lifeways, treaty-reserved rights, and resource stewardship of Tribal Nations, including Ojibwe communities across the Upper Midwest. Despite ongoing stocking efforts and harvest regulations, many lake systems have experienced persistent declines in natural recruitment, prompting resource agencies to investigate the underlying causes. One such system is …

Decomposition Study Using Pigs In Southeastern Nebraska During The Fall And Winter Seasons, Ryan Bodine

Department of Anthropology: Theses and Student Research

When an individual is found deceased, one of the tools used in the identification process is estimating the post-mortem interval (PMI). This estimate is used to determine how long an individual has been deceased once their remains are found. To estimate an accurate PMI, knowing how decomposition is affected by external factors is key. The transition period from fall to winter in southeastern Nebraska consists of fluctuating temperatures as the seasons transfer from fall to winter. This thesis investigates how decomposition is affected during this transition period while also looking at two different environments that are common in Nebraska, prairies …

Nadh Flim Reveals Cellular Bioenergetics And Mitochondrial Morphology During Drosophila Convergent Extension, Maria Espana Pena

Graduate Theses and Dissertations

Mitochondria are dynamic organelles that can fragment or fuse to support different bioenergetic demands and cellular processes, although the role of mitochondrial fission and fusion during embryonic development is not well understood. Fluorescence lifetime imaging (FLIM) of the mitochondrial cofactor NADH can be used to visualize mitochondrial networks and infer aspects of cellular bioenergetics in a label-free manner. We used NADH FLIM to test whether germband cells undergo changes in cellular metabolism during Drosophila convergent extension (CE)––a process in which hundreds of epithelial cells undergo coordinated intercalation to elongate the embryo. Contrary to our expectations, we did not observe significant …

Genomic Surveillance Of Guillain–Barré Syndrome-Associated Genes In Campylobacter Jejuni Across Human And Non-Human Reservoirs, Emma Doughty

Biological Sciences

Campylobacter jejuni is a leading cause of foodborne illness and a major trigger of Guillain–Barré Syndrome (GBS), an autoimmune neuropathy caused by molecular mimicry between bacterial lipooligosaccharides (LOS) and host nerve gangliosides. While prior genomic studies have focused primarily on human clinical isolates, the prevalence and distribution of GBS-associated genes in non-human reservoirs remain poorly characterized. This study used genomic datasets derived from analyses of human and non-human C. jejuni isolates to assess the distribution of GBS-associated genes, with a focus on the neuABC sialylation pathway. Results demonstrate that these genes are present in both host types, across multiple geographic …

Cell-Type Specific Control Of Visual Fixation In Drosophila Melanogaster, Meagan Leung

Biological Sciences

Navigation in complex environments requires precise visual processing. To move effectively through their surroundings, animals must orient toward and maintain fixation on objects of interest to preserve a stable heading. However, the neural mechanisms underlying this behavior remain poorly understood. We use Drosophila melanogaster as our model organism because its visual behavior can be precisely measured and the availability of genetic tools which enables us to perturb the underlying neural circuits. Using a closed-loop virtual reality environment combined with locomotion tracking, we developed a stimulus protocol that reliably elicits fixation responses. To determine whether specific visual neurons drive fixation responses, …

Structural Evidence For Innervation Of A Single Epitheliomuscular Cell By Multiple Sensory Neurons In The Sea Anemone Nematostella Vectensis, Aparajita Das

Graduate Theses and Dissertations

Abstract Here, I report new ultrastructural evidence for multineuronal innervation (many-one) of a single epithelia-muscular cell in sea-anemone cnidarian Nematostella vectensis. Using Serial Block-Face Scanning Electron Microscopy (SBF-SEM) and ImageJ, I found that EMCs are located at the base of ectoderm, with an elongated cell body that includes basal processes, a bilobed nucleus, and myofibrils aligned parallel to the basal surface along with their structural quantification. Notably, I found multiple mechanosensory neurons form synapses with a single EMC. These findings enhance our understanding of cnidarian neuromuscular organization and reveal that coordination between sensory and contractile systems in N. vectensis is …

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 …

Mitogenomic And Physiological Comparison Between Wild And Domesticated Congeners, Nicholas Enriquez

Open Access Theses & Dissertations

Domestication is a process in which wild populations are morphologically and/or behaviorally manipulated through selective breeding to become optimized for living in captivity. Consequently, many traits become quickly and significantly diverged from their ancestral, wild lineages, a process known as part of domestication syndrome. Captive breeding of mallards (Anas platyrhynchos) was one of the last major successful domestication events resulting in dozens of recognized breeds today. Many breeds were optimized for either ornamental or agricultural purposes (i.e., meat and/or egg production), but the game-farm mallard was specifically bred for sport hunting. In North America, the use of game-farm mallards to …

Drug Repurposing Against Giardia Targeting Lipid Rafts, Extracellular Vesicles, And Sphingolipid Synthesis, Breanna Chantal Pence

Open Access Theses & Dissertations

Giardia lamblia is a protozoan parasite responsible for the intestinal disease giardiasis worldwide. Giardia is one of the major intestinal parasites in the world, with over 500,000 new cases annually. Symptoms of giardiasis include diarrhea, abdominal pain, and nausea. Children are particularly vulnerable to giardiasis, with cases of malnutrition, stunted growth, and cognitive impairment in countries where the disease is endemic. Giardia consists of two morphologic forms: an infective cyst which transmits the disease and a motile trophozoite which attaches to the epithelium of the small intestine during infection. Metronidazole is a common treatment for giardiasis, but cases of toxicity …

High-Resolution Mapping Of Brainstem Feeding Circuits: A Framework For Targeted Neuroscience Tools, Geronimo Tapia

Open Access Theses & Dissertations

The neural control of energy balance is mediated in part by distributed brainstem circuits that integrate metabolic, visceral, and hormonal signals to coordinate appropriate motivated behaviors and autonomic responses. Despite extensive study, the precise neuroanatomical architecture regulating metabolism remains incompletely defined within standardized atlas frameworks. This work addresses that gap through complementary studies examining an acute glycemic challenge methodology known to stimulate feeding, the acute delivery of an anorexigenic-associated neurohormone, and the chemoarchitecture of a major feeding-related region, the parabrachial nucleus. First, utilizing 2-deoxy-D-glucose (2-DG) induced glucoprivation, we map the rapid response of dorsal medullary neuronal populations with high spatial …

Determining Zap-70 Signaling Pathways Mediated By Ccr7 In Tcr T Cell Activation, Vivian Torres

Open Access Theses & Dissertations

Activation of T lymphocytes is the main event that occurs in the adaptive immune response after engagement of the T cell receptor (TCR) with the peptide of the major histocompatibility complex (pMHC) molecules that are demonstrated by antigen presenting cells [1]. A key step in this process is the recruitment and activation of the zeta chain associated protein of 70 kDa (ZAP-70). ZAP-70 couples TCR engagement to downstream intracellular signaling pathways through phosphorylation of tyrosine residues within intracellular tyrosine activation motifs (ITAMs) [2]. Although there have been extensive studies on the signaling response through TCR activation, the regulatory influence of …

Characterization Of The Antiviral Activity Of Mouse Schlafen Proteins, Wendy Paola Alvarez Leal

Open Access Theses & Dissertations

The goal of this work was to characterize the anti-viral role of mouse Schlafen8 and Schlafen9. Expression of these proteins is induced by type I interferon in response to viral infections. Importantly, their human functional orthologs exhibit anti-viral functions, and the structural element required for these activities are conserved in Schlafen8 and Schlafen9. Therefore, it is expected that these proteins will also impair viral replication. An important limitation in this field is that the anti-viral function of human SLFNs has been evidenced only in in vitro cellular models. No informative mutations have been described in human populations so far. Thus, …