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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 …

Mechanisms Of Life History Trade-Offs In The Evolution Of Eusociality, Frances Katherine Hunter

All Graduate Theses and Dissertations, Fall 2023 to Present

When faced with stressors such as pathogen infection, organisms must invest energy in defense or risk death. Because resources are limited, mounting an immune response often comes at the expense of other costly activities such as reproduction. The costs of immunity are shaped by factors including behavior, nutrition, age, and evolutionary history.

Social insects (e.g., ants, bees, and wasps) offer a powerful system for studying these trade-offs because queens in these colonies appear to escape them—living long lives while reproducing prolifically. Bees, which include species that range from those which nest solitarily to those with complex social systems and many …

Cannabis: A Model Plant To Study Light-Mediated Reproductive Development, Madigan J.H. Eckels

All Graduate Theses and Dissertations, Fall 2023 to Present

Cannabis (Cannabis sativa) is a plant of increasing importance for research, medical, recreational, industrial, and agricultural purposes, but a strict legal landscape means that it was chronically understudied. Now that research institutions can utilize this plant for study, we require updated terminology to describe various cannabis flowering types that occur under ideal and non-ideal growing conditions. We introduce new flowering terminology and describe them in text and with photographs.

Plants use light as a resource to power photosynthesis, and a greater total sum of photons generally increases yield. In controlled environment agriculture where growers utilize light fixtures instead …

Exploring The Correlation Between Malnutrition And Food And Nutrition Insecurity In Inflammatory Bowel Disease, Heather Burr

All Graduate Theses and Dissertations, Fall 2023 to Present

Inflammatory Bowel Disease (IBD) may increase the risk of malnutrition because of nausea, vomiting, diarrhea and restrictive eating. In addition, patients with IBD may experience food and nutrition insecurity. Therefore, we conducted an online survey to assess risk of malnutrition and food and nutrition insecurity among adult patients with IBD in outpatient and community settings. Patients were recruited between July and December 2025, aiming to reach adults in the Rocky Mountain Region diagnosed with IBD. Data collected included demographics, health-related factors, risk of nutrition insecurity, risk of food insecurity, and barriers and facilitators to dietary management of IBD.

Fifty-seven patients …

Effect Of Agroecological Feeding Systems Of Dairy Cattle On The Nutritional Composition Of Milk, Sree Bhavya Immadi

All Graduate Theses and Dissertations, Fall 2023 to Present

How food is produced can influence both its nutritional quality and its impact on the environment. In recent years, regenerative (agroecological) farming practices have gained attention for their potential to improve soil health, biodiversity, and the nutritional value of foods. In dairy production, these practices often involve growing more diverse forage crops, reducing soil disturbance, and relying less on monoculture-grown feed rations. However, there is still limited real-world evidence showing how these practices affect the nutritional composition of milk produced on commercial dairy farms.

This dissertation explores how regenerative feeding and feed production practices influence the nutritional quality of milk, …

Dried Water Treatment Residuals Might Be An Option To Reduce Soluble Reactive Phosphorus Release From Soils, Katie B. Mckay

Biological and Agricultural Engineering Undergraduate Honors Theses

Nonpoint source pollution from agricultural landscapes contributes to freshwater eutrophication, with legacy phosphorus (P) in soils potentially driving soluble reactive phosphorus (SRP) losses to surface waters. The objectives of this study were to evaluate SRP adsorption by dried water treatment residuals (WTRs) produced by Beaver Water District, quantify reductions in soil SRP release across increasing WTR application rates, and compare dried WTR performance to prior WTR studies.

Dried WTRs (~98% solids) were assessed using batch sorption experiments and soil core incubations. Phosphorus sorption was measured by mixing WTRs with CaCl₂ solutions containing increasing SRP concentrations and fitting results to …

Cross-Facility Reliable Deep Learning Based Beef Marbling Assessment Via Unsupervised Domain Adaptation Regression, Samuel Vinson

Biological and Agricultural Engineering Undergraduate Honors Theses

Inconsistent quality grading in beef production leads to inefficiencies, economic disparity, and consumer mistrust. While USDA meat grading traditionally relies on skilled visual inspectors, these human evaluations suffer from cross-facility variability and subjectivity. This paper introduces the first known application of unsupervised domain adaptation regression for cross-facility beef marbling score prediction—an innovation that improves generalization across diverse environments in the beef supply chain. Utilizing numerical scores ranging from 100-900, the research employed convolutional neural networks (CNNs), including ResNet, VGG, and AlexNet architectures. The study specifically introduced and validated a unified unsupervised domain adaptation regression method using the ResNet-50 architecture to …

Preserving The Past: Exploring The Last Frontier's Ecosystem Shifts And Biodiversity Of The Tallgrass Prairies, Gisell Maldonado, Amelia Villaseñor

Anthropology Undergraduate Honors Theses

In North America, grasslands are a cornerstone of the environment. Historically, the tallgrass prairie was expansive and reached from Manitoba in Canada to Texas. Today this unique ecosystem is highly fragmented and reduced, but it remains an important ecosystem for biodiversity and cattle management. While there are many complex ecological interactions in the prairie, recent research shows that large herbivores are vital in maintaining grasslands through grazing and other behaviors that reduce woody encroachment and support nutrient cycling. Here, we examine cow and bison dietary behaviors and connect these to the ecosystem services provided by these large herbivores. In the …

Historical Comparison Of Bridal Fashion Symbolism: Contrasting Queen Elizabeth Ii, Princess Diana, And Catherine, Princess Of Wales, Rebecca O'Dea

Apparel Merchandising and Product Development Undergraduate Honors Theses

The purpose of this study was to gain understanding and insight into the profoundness behind the practice of dress. Throughout history, royal attire has been used to demonstrate aspects about the individual and regency. Royal fashion served as an excellent area to narrow in on, due to the influential status, and high standards expected of their appearance and actions. This research project studied members of British royal family, Queen Elizabeth II, Princess Diana, and Catherine, Princess of Wales, and analyzed fashion elements of their wedding dresses. The examination of bridal fashion was conducted through thematic framework determining if the concepts …

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 …

Sequential Products Of Anaerobic Denitrification In Calcareous And Noncalcareous Soils By Use Of The Gas Chromatograph, Grant S. Cooper

All Graduate Theses and Dissertations, Fall 2023 to Present

The sequential products of anaerobic denitrification were determined on seven Western soils (four alkaline, two acid, and one neutral) by soil and gas analysis. The soils with 1% alfalfa and added KNO3 were incubated at moistures slightly greater than field capacity and with an atmosphere of He. The soils and gases were periodically analyzed and balance sheets prepared. The sequence of NO3-->NO2-->N2O-->N2 operated in all soils. The rates of nitrogen interchanges and maximal amounts of nitrate, N2O2 and N2 were determined. From this data it was postulated that the rate-limiting process for denitrification in acid soils is …

Evaluation Of Fertilizer Recommendation And Soil Amendment Impacts On Crop Production In The Intermountain West, Megan Baker

All Graduate Theses and Dissertations, Fall 2023 to Present

Fertilizers improve crop yield and quality by supplying crops with essential nutrients, but can also be a significant input cost. Determining what nutrients and rates to apply for optimal crop growth can be difficult, leading many growers to use external sources for these decisions. Land-grant universities are a common source for fertilizer recommendations, but often based on decades-old research and should be evaluated periodically to verify effectiveness and calibrated to current soil analysis methods. Current Utah State University (USU) guidelines for sulfur (S) and zinc (Zn) were tested across Utah in on-farm trials in 2021-2025. Zinc applications of 5 or …

Forage Responses To Biological Inoculant And Seed Rates In The Intermountain West, Roy Reid

All Graduate Theses and Dissertations, Fall 2023 to Present

Improving the efficiency of fertilizer and seed use is increasingly important for forage producers in the Intermountain West, where alfalfa and silage corn form the foundation of dairy and livestock feed. This thesis evaluates two strategies designed to boost crop productivity: microbial fertilizer coatings and variable-rate seeding.

The first study examined whether Powercoat®, a fertilizer-applied microbial inoculant, could enhance yield, forage quality, or soil phosphorus availability in alfalfa grown on four commercial fields in northern Utah. Across all locations, fertilizer increased yield at only two sites, and Powercoat did not provide additional improvements in yield, forage quality, or soil nutrient …

Post-Wildfire Erosion And Biogeochemistry: Integrating Aerial Imagery And Soil Testing To Assess Landscape Recovery, Justin A. Allred

All Graduate Theses and Dissertations, Fall 2023 to Present

After a wildfire, land managers are required to monitor large tracts of land with limited time and budgets. Traditionally, tracking landscape recovery is a time intensive process. This research explored the effectiveness of using drones (UAVs), strategic soil sampling, and computer modeling as additional tools for land managers in order to monitor the recovery more efficiently.

By using drones to collect aerial imagery and using machine learning, plant regrowth was monitored in back-to-back years. The machine learning model performed well at telling broad groups apart (trees vs grass) but it struggled to identify differences between plant species. Because many plants …

Influence Of Predation Risk On Elk Feeding Behavior In A Multi-Predator Environment, Rosemarie C. Pugh

All Graduate Theses and Dissertations, Fall 2023 to Present

Sometimes predators don’t just affect prey by killing them, they can also change how prey behave. For example, animals may spend more time watching for danger and less time eating, which could affect their health and survival. In Yellowstone National Park, past research has suggested that elk may reduce feeding because they are trying to avoid predators like wolves and cougars. However, most previous studies have only looked at elk behavior during the daytime and have often looked at responses from single predators rather than multiple.

In this study, I used high-resolution tracking collars equipped with motion sensors to directly …

Mapping Spatial Variability For Precision Management In Utah’S Tart Cherry Orchards, Kurt T. Wedegaertner

All Graduate Theses and Dissertations, Fall 2023 to Present

Tart cherry orchards are a major part of the agricultural landscape in Utah, but producing cherries is becoming increasingly difficult and expensive. Orchard land is not uniform. Some parts of a field grow strong, healthy trees, while other parts struggle because of differences in soil, water, and landscape. Even though these differences exist, orchards are usually managed the same way everywhere. Over many years, this causes some trees to become much larger than others, making orchards harder to manage, less efficient to harvest and prune, and more costly to maintain.

This research focused on finding practical ways to measure these …

Food-Form Delivery Of Spore-Forming Probiotics As An Alternative To Gavage In Animal Models, Aubreyona Faith Migliori Skalka

All Graduate Theses and Dissertations, Fall 2023 to Present

Western dietary patterns are characterized by nutrient-poor, calorie-rich diets and have been linked to poor health outcomes and gut inflammation phenotypes. Probiotics are often taken to support gut health, but many beneficial bacteria do not survive transport through the digestive system to produce any effect. Spore-forming bacteria, such as Bacillus coagulans, are more resilient due to their hardy outer coat which aids in survival through many obstacles encountered in the gastrointestinal tract, including acidic stomach conditions. In research studies, probiotics are usually given to mice through a procedure called oral gavage, where a tube is used to deliver the …

Production Of Hydrolyzed Lactose Syrup From The Acid Whey, Aubrey Jean Arbon

All Graduate Theses and Dissertations, Fall 2023 to Present

Acid whey has gained significant attention within the dairy industry due to its complex matrix and the processing challenges. This by-product contains lactose that can be isolated, hydrolyzed, and further processed to produce hydrolyzed syrup. To optimize lactose utilization, it is essential to fine-tune the kinetics of the β-galactosidase enzymes used for lactose hydrolysis. To analyze sugars in acid whey, and LC-MS-based chromatographic method was developed. Once the method was developed, the kinetics of β-galactosidase were optimized with respect to enzyme concentration, pH, and temperature. The goal was to achieve the highest possible lactose hydrolysis. The hydrolyzed acid whey was …

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 …

Which Energy Expenditure Equation Is Most Accurate In A Field-Based Setting?, Merrill C. Ward

All Graduate Reports and Creative Projects, Fall 2023 to Present

Several energy expenditure prediction equations for walking on varied terrain exist; however, these predictions are often theoretical and have not undergone rigorous field testing for accuracy. Field research on this topic is sparse. The aim of this study was to determine if any existing energy expenditure prediction equations are accurate in a field-based setting with load and gradient being taken into account (i.e., under conditions that are most applicable to day hiking). This was done by directly measuring relative VO₂ (ml/kg/min) of study participants and comparing these direct measurements to the values generated from the existing prediction equations. Fifteen …

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 …