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The Genetic Basis Of High Transformation Efficiency In The Model Yeast Saccharomyces Cerevisiae, Mary Kathryn E. Cheek

Biological Sciences Undergraduate Honors Theses

Transformation, a type of horizontal gene transfer, describes the uptake, maintenance, and integration of environmental DNA by cells. Despite the known effects of transformation on evolutionary processes, little is known about the genetic basis of this phenomenon. Saccharomyces cerevisiae is a eukaryote able to transform at quantifiable rates when made chemically competent and treated with a heat shock. S. cerevisiae also has variation in transformation efficiencies between various strains, and high recombination rates allow for sufficient allele “shuffling” in intercross populations. This project utilizes a bulk segregant analysis approach to compare sequencing data between transformant pools and non-transformant pools of …

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 …

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 …

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 …

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 …

Differential Salinity Tolerance And Compositional Shift In Zooplankton Communities From Coastal And Inland Wetlands, Marisa Contreras

Theses, Dissertations and Culminating Projects

Anthropogenic salinization from road salt application has degraded freshwater ecosystems across the United States, yet the tolerance of freshwater communities to elevated salinity may depend on their historical exposure. Coastal systems experience natural salt intrusion through tides and storm events, potentially fostering greater salinity tolerance amongst resident organisms, while inland systems lack this exposure history. To investigate, I studied the abiotic and biotic responses of zooplankton communities from four wetlands across a salinity gradient to assess tolerance to experimental salt exposure. Two inland freshwater wetlands are subject to anthropogenic salinization from road salt runoff, while two coastal wetlands experience natural …

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 …

Rehumanizing Anatomized Individuals: Using Osteobiographies As A Step Towards Reparative Justice, Lillie C. Turpin

Department of Anthropology: Theses and Student Research

In 1985, India banned the export of human remains. This ended the major trade route for primarily US and European anatomical supply companies. Until this point, companies like Carolina Biological Supply exploited and erased vulnerable people's identities, molding them into anonymous anatomical specimens. This study investigates the life and postmortem history of twenty-five individuals, previously used as anatomical specimens, housed at the University of Nebraska–Lincoln. Using an osteobiographical approach, this research reconstructs aspects of these individuals' lived experiences and examines how anatomical preparation practices reflect structural violence and apathy.

Skeletal analysis of twenty-five individuals revealed a range of biological profiles, …

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 …

Genetic Screen For Regulators Of Pol4, A Dna Repair Polymerase In Saccharomyces Cerevisiae, Pasang Dolma Sherpa

Theses and Dissertations

In Saccharomyces cerevisiae, DNA polymerase 4 (POL4) is the beta repair polymerase, the product of the POL4 gene, and is involved in base excision repair (BER) and microhomology-mediated end joining (MMEJ). Despite its involvement in these repair pathways and its conservation across eukaryotes, deletion of POL4 shows no detectable phenotype under standard laboratory conditions. I hypothesized that unknown genes act as backup systems, providing redundant activities that allow pol4Δ cells to survive. To test this, a genetic screen for mutants showing synthetic lethality with pol4Δ was implemented. I constructed a strain lacking the POL4 gene and carrying …

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 …

Unveiling The Biochemical Pathway Responsible For Ankyloglossia (Tongue-Tie) By Tracking Enzymatic Activity Of Apoptosis Pathways, Becca Ringstad

Celebrating Scholarship and Creativity Day (2018-)

Ankyloglossia (Tongue-tie) is a condition that is caused by failed cellular degeneration leading to a short lingual frenulum. This short lingual frenulum tethers the tongue to the bottom palate of the mouth and leads to problems, including breastfeeding for infants, depriving them of important proteins that build the gut microbiome, strengthen the immune system, and fight off antigens. If left untreated, it leads to problems with speech articulation, airway development, and obstructive sleep apnea. Treatment involves a frenectomy, which is the release of the short lingual frenulum using surgical scissors or a laser. Ankyloglossia can occur with conditions such as …

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 …

Geospatial Science And The Changing Environment: Applied Methods For Sustainable Agriculture And Landscape Management, Harrison Wakefield Smith

Graduate Theses and Dissertations

Rapid environmental change is disrupting agricultural productivity, ecological function, and the long-term resilience of managed landscapes. At the same time, the rapid growth of geospatial data science has improved our understanding of environmental change and increasingly is being used to improve sustainability in agricultural and environmental management. However, critical gaps remain that limit the applicability of data-driven insights in landscape management. This dissertation investigates the potential of geospatial analytics for sustainable agriculture and landscape management, with a focus on applied methods that operate across spatial and temporal scales. Using field, landscape, regional, and national datasets, it explores the capabilities and …

Aggregation And Collation Of Texas Crayfish Museum Specimens To Determine Their Current Conservation Statuses, Adrian Alvarez

Biology Theses

Crayfish account for over half of the macroinvertebrate biomass in many ecosystems and serve as crucial bioindicators because of their behavioral and physiological adaptability to environmental changes. Despite being home to approximately 52 native crayfish species, Texas currently lacks protective regulations. This gap is primarily because of insufficient information regarding their distribution and occurrences within the state, including their statuses as Species of Greatest Conservation Need (SGCN). This study focuses on compiling and comparing crayfish museum records with current iNaturalist field survey data across Texas to address these knowledge gaps and recommend updates to SGCN statuses. Five species not currently …

Developing Training And Streamlining Training Management Process For Smithfield Fire Department Employees In Aha, Naemt, And Aap Certifications, Michael Christopher Popa Ii

Undergraduate Honors Capstone Projects

The rapid operational expansion of the Smithfield Fire Department and EMS (SFD)—marked by a 300% increase in call volume and a transition to a fully professional, independent paramedic service—exposed critical systemic inefficiencies in clinical preparedness and personnel credentialing. This project addresses the "HALO Paradox," wherein high-acuity, low-occurrence emergencies require expert-level proficiency that cannot be maintained through call volume alone. Historically, the agency relied on fragmented, external continuing education (CE) that incurred high financial costs, lacked equipment standardization, and created administrative bottlenecks during biannual recertification cycles. The central objective of this capstone was to engineer a sustainable, in-house training infrastructure that …

Behind The Smile: A Qualitative Study On Dentist Burnout And Workplace Satisfaction In Cache Valley, Luke Thomas Hatch

Undergraduate Honors Capstone Projects

This qualitative research study examined satisfaction, stressors, and burnout among dental professionals in Cache Valley, Utah. Eight practitioners at various points in their careers were interviewed with a range of specialties including general dentistry (n = 3), pedodontics (n = 3), oral and facial surgery (n = 1), and orthodontics (n = 1). Analysis of the interviews showed that level of clinical autonomy was a primary factor influencing burnout levels. Stress levels in more experienced practitioners and owners tended to be lower than those who worked in multiple practices (multi-doctor) or with corporations. Individuals in these environments reported higher levels …

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 …

Bio 23 Human Anatomy & Physiology I Syllabus, Rujin Tian

Open Educational Resources

The syllabus for BIO 23 contains a course description, course objectives, course readings divided by week and a link to an OER textbook.

Bio 24 Human Anatomy And Physiology Ii, Rujin Tian

Open Educational Resources

The syllabus for BIO 24 contains a course description, course objectives, course readings divided by week and a link to an OER textbook.

Examining Pathogenic Vibrio Abundance And Environmental Controls Across Macroalgae, Sediment, And Oysters, Alexandra H. Geisser, Abigail K. Scro, Roxanna Smolowitz, Robinson W. Fulweiler

Arts & Sciences Faculty Publications

Climate change is accelerating the geographic spread and abundance of pathogenic Vibrio species in coastal waters, posing growing threats to ecosystems and human health. We investigated the abundance and pathogenic gene presence of V. vulnificus and V. parahaemolyticus across three common estuarine substrates (macroalgae, sediment, and oysters) in a temperate estuary. Macroalgae consistently harbored the highest Vibrio counts in conjunction with elevated pathogenic gene frequencies, while oysters contained the lowest. Environmental conditions related to Vibrio abundance were substrate and Vibrio species specific. Temperature and salinity were most closely related to pathogenic Vibrio abundance in oysters. In contrast, pathogenic Vibrio abundance …

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 …

Optimizing Citriculture In South Texas With Endemic Hlb, Ruth Lilia Galan

Theses and Dissertations

The Texas citrus industry has a long history of resilience, rebounding from environmental and economic disasters. Over the last decade it has endured several hurricanes, freezes, pests and diseases. Huanglongbing (HLB), a graft-transmissible disease caused by Gram-negative bacterium Candidatus Liberibacter asiaticus which is vectored by the Asian citrus psyllid (ACP) (Diaphorina citri Kuwayama), is an endemic citrus disease posing serious threat to the long-term viability of the industry. Rapid production of high quality nursery trees and effective protection of young citrus transplants from HLB are critical for long term sustainability of citriculture in this region. Studies were performed to improve …

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 …