Digital Commons Network^™

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 …

Effects Of Serum And Commercial Serum-Free Media On Development Of In Vitro Produced (Ivp) Embryos In Cattle, Kyla Miller

All Graduate Theses and Dissertations, Fall 2023 to Present

Serum-containing media has been shown to increase incidence of large offspring syndrome and to alter gene expression, protein synthesis, and cell signaling. These factors together can result in increased pregnancy loss when combined with assisted reproduction technologies. However, there are very few direct comparisons of commercial serum-free media (IVF Bioscience™) and serum-containing media on both IVF and cloned embryo development in cattle. The aim of this study was to determine the role of serum in oocyte maturation and subsequent embryo development. Three culture systems, including in vitro maturation (IVM) and in vitro culture (IVC), were used in this study. Both …

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, …

Ecological Insights And Management Implications Of The Global Migratory Connectivity Of Green Turtles, Jaime Restrepo, Dina Nisthar, Harris Wei-Khang Heng, Lily K. Bentley, Corrie Curtice, Sarah Deland, Ei Fujioka, Patrick N. Halpin, Sarah K. Poulin, Roldán A. Valverde

School of Earth, Environmental, & Marine Sciences Faculty Publications

Aim

Green turtles are a widely distributed and highly migratory species; despite extensive data on their movement, there is no species-specific global synthesis on the subject. Based on three decades of published literature and building on previous global analyses, we developed a global network model of migratory connectivity for green turtles to better understand their spatial biology.

Location

Global.

Time Period

1990–2022.

Major Taxa Studied

Green Sea Turtle (Chelonia mydas).

Methods

We conducted a structured literature review extracting georeferenced information on the movement of green turtles from 1990 to 2022, aggregating this information into a single connectivity model, …

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 …

The Rise And Fall Of The World's Greatest Marine Biodiversity Hotspot, Alexandre C. Siqueira, Kiessling, Nussaïbah Raja, David R. Bellwood

Research outputs 2022 to 2026

Habitat condition and area shape global species distributions, with shallow-water reefs hosting a disproportional share of marine biodiversity. Although reef area is a well-established predictor of marine species richness, its historical context is less well understood. Here, we show that the rise of tropical marine biodiversity is closely tied to reef expansion in space and time. During the Early/Mid Miocene (23 to 11.6 million years ago), Indo-Pacific reefs reached unprecedented size and thickness, surpassing any reef systems in the past 66 million years. These massive reefs, likely driven by unique environmental, biotic, and tectonic conditions, fostered the expanding diversity and …

Comparing Microbial Communities Of Diseased And Healthy Isopora Palifera Corals And Adjacent Waters At The Cocos (Keeling) Islands, Sophie Preston, Jacquelyn Jones, Megan J. Huggett, Arne A.S. Adam, Nicole E. White, Kar Chun Tan, Zoe Richards

Research outputs 2022 to 2026

Growth anomalies (GAs) are coral diseases characterised by tumour-like skeletal lesions reported globally, yet their causes remain poorly understood. Microorganisms are integral to coral health, but the role of bacterial communities in GAs remains unclear. We investigated an outbreak of GAs in Isopora palifera at the Cocos (Keeling) Islands using 16S rRNA amplicon sequencing to compare bacterial communities of GA-affected and asymptomatic corals, surrounding water and potential pollution sources. Significant differences in bacterial beta diversity were observed across sites, with an interaction between location and coral health status. Coral and water samples hosted distinct microbial communities, but there was no …

Arkansas Soybean Research Studies 2024, Jeremy Ross

Arkansas Agricultural Experiment Station Research Series

The 2024 Arkansas Soybean Research Studies includes research reports on topics pertaining to soybean across several disciplines from breeding to post-harvest processing. Research reports contained in this publication may represent preliminary or only data from a single year or limited results; therefore, these results should not be used as a basis for long-term recommendations. Several research reports in this publication will appear in other University of Arkansas Division of Agriculture’s Arkansas Agricultural Experiment Station publications. This duplication is the result of the overlap in research coverage between disciplines and our effort to inform Arkansas soybean producers of the research being …

Solvent-Dependent Proteome Profiling In Edible Mushrooms (Hypsizygus Marmoreus And Agaricus Bisporus), Tanvir Ahmed, O'Lone, Angéla Juhász, Utpal Bose, Kenneth U. Agbo, Netsanet Shiferaw Terefe, Michelle L. Colgrave

Research outputs 2022 to 2026

This study compared five solvents - urea, carbonate-bicarbonate, citrate, phosphate, and water - for their ability to extract proteins from beech (BM) (Hypsizygus marmoreus) and Swiss brown (SB) (Agaricus bisporus) mushrooms. Using mass spectrometry-based proteomics and bioinformatics, we found that urea produced the highest total protein identifications by data-dependent acquisition at 1% false discovery rate (FDR): BM: 1739, SB: 1907; and by data-independent acquisition: BM: 1969, SB: 2172 proteins, especially enriching cytosolic and ribosomal proteins. Carbonate-bicarbonate favoured the extraction of metabolic and translational proteins, while citrate targeted extracellular and membrane-associated proteins related to cell wall dynamics. Phosphate-enriched catalytically active proteins, …

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 …

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 …

Effects Of Mineral Supplementation On Ovine Performance, Forage Selectivity, And Rangeland Utilization In Southern Utah, Ryan A. Spurling

All Graduate Theses and Dissertations, Fall 2023 to Present

Sheep producers in the Intermountain West region of the US rely on productive rangeland ecosystems that vary widely in forage composition and nutrient availability. As such, supplementation is often necessary to offset dietary deficiencies. Soils and forages grown on rangelands are known to be highly variable in mineral content. Even so, a third to half of the producers in the Intermountain West choose not to provide a complete mineral supplement. Rangeland environments are often characterized by rugged geographical features that make optimal supplement placement difficult. New advances in technology have allowed us to measure individual animal intake on rangelands via …

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 …

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 …

Recovery Timeframe Is A Critical Component In Preserving Carbon Stocks In Disturbed Tropical Seagrass Meadows, Taylor Renee Condron, Timothy M. Smith, Paul H. York, Nicholas J. Murray, Pere Masque, Michael A. Rasheed

Research outputs 2022 to 2026

Seagrass meadows, though covering a small percentage of the ocean floor, play a critical role in marine carbon sequestration. However, the mechanisms behind this role remain uncertain due to challenges in mapping seagrass extent and flux, accounting for spatial variation in carbon storage, and incorporating site-specific histories. This study investigates the effects of short-term (≤10 years) seagrass loss on sediment carbon stocks within a large seagrass meadow in the Great Barrier Reef region. Using remote sensing data to construct a seagrass recovery timeline, combined with field sampling and assessments of ecological factors, we found higher sediment organic carbon in areas …

Exploring The Spectrum Of Anxiety During Concussion Recovery: A Comprehensive Examination Of Symptom-Based Anxiety Disorders, Kori J. Durfee

Graduate Theses and Dissertations

Background: Anxiety is common following a concussion, arising from both psychosocial and physiological changes, and can manifest in diverse ways. Despite its complexity and association with worse outcomes, post-concussion anxiety is often assessed as a single construct. Characterizing anxiety presentations following injury may improve the identification of clinically meaningful symptoms and help inform future targeted interventions that can improve concussion outcomes. Purpose: The primary purpose was to determine if symptom-based anxiety disorders occur in adults with concussion and identify pre- and post-injury predictors associated with these disorders. Additionally, the clinical utility and predictive abilities of symptom-based anxiety disorders and variability …

Applying Motivational Interviewing-Based Health Coaching Within An Existing Exercise Referral Program: A Cost, Implementation, And Effectiveness Analysis, Zachary Joseph Friedman

Graduate Theses and Dissertations

Higher levels of physical activity (PA) are known to be associated with lower rates of chronic disease and better quality of living. However, population-wide deficits in PA continue to demand strategies for supporting PA-related behavior change. Health coaching represents a promising intervention strategy for behavior change, but its effectiveness in generally healthy, non-clinical populations is not clear. The purpose of this project was to evaluate the feasibility, cost, and effectiveness of integrating student-delivered, motivational interviewing (MI)-based health coaching into an existing university-based exercise referral program (ERP). Additionally, this study aimed to use students as health coaches, and to document training …

Low Methane Emissions From Nutrient-Rich Former River Channels In A Hydrologically Managed Dryland Delta, Siena Stassi, Jude A. Benavides, Chu-Lin Cheng, Marcelo Gomes Da Silva, Nicholas E. Ray, Nathan O. Barros, Rafael M. Almeida

School of Earth, Environmental, & Marine Sciences Faculty Publications

Anthropogenic stresses in dryland regions can alter hydrology, salinization, and biogeochemical processes. How these pressures influence methane (CH4) cycling and emissions from aquatic ecosystems remains poorly understood. Over the course of 1 year, we measured diffusive and ebullitive CH4 emissions from resacas—shallow, hydrologically managed distributary channels prevalent throughout the Lower Rio Grande Valley along the US–Mexico border. Despite warm, nutrient-rich waters, CH4 emissions from resacas were low, and more comparable to rates observed in estuarine systems. CH4 fluxes were positively related to temperature but negatively related to salinity and rainfall. Elevated salinity, driven by evaporation and source water from the …

Landscape Connectivity And Wildlife Access To Water Across An International Border: Barriers And Opportunities For Facilitating Transboundary Movement, Bogdan Chivoiu, Erin L. Koen, Michael J. Osland, Christopher A. Gabler, Jerald T. Garrett, Ernesto Reyes, Stephanie A. Bilodeau, Mitch A. Sternberg, Jude A. Benavides, James Martinez

School of Earth, Environmental, & Marine Sciences Faculty Publications

Rapid global acceleration in the construction of physical barriers along international borders has greatly influenced biodiversity and animal movement. Physical barriers can fragment landscapes, hinder access to essential resources, impact long-distance migrations, and inhibit dispersal and gene flow. The effects of physical barriers on animal movement and landscape connectivity can be exacerbated in dryland environments where access to water is a limiting factor. In recent decades, the construction of border barrier infrastructure has accelerated along the international boundary between the United States and Mexico. Here, we used a landscape connectivity model to investigate the effects of barriers on wildlife access …

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, …

Impact Of Inhibiting Mitochondrial Calcium Uptake On Calcium Homeostasis And Postmortem Metabolism In Porcine Muscle, Fatema Rahaman Mishu

All Graduate Theses and Dissertations, Fall 2023 to Present

After harvesting the animal, pork muscle continues to undergo changes as it turns from muscle into meat. During this early period, the muscle uses up energy and produces acid, which lowers pH and can affect important quality traits such as color and how well the meat holds water. A key driver of these early changes is calcium, a natural mineral inside muscle cells that helps control contraction and energy use. In this study, we tested whether mitochondria (the cell’s “powerhouse”) help control calcium after harvest and, in turn, influence early postmortem changes in pork. We used a research compound (DS16570511) …

Alfalfa Yield, Quality, And Nutrient Use Response To Pivot Sprinkler Technology, Deficit Irrigation, And Genetics, Dakota Boren

All Graduate Theses and Dissertations, Fall 2023 to Present

In water limited environments, alfalfa is often criticized for its high water use, prompting implementation of new irrigation technologies, deficit irrigation, and adapted crop genetics. Cumulative potential benefits from combining, or stacking, these water-optimizing practices have not been identified. The objective of this on-farm research study was to determine how irrigation technologies, deficit irrigation, genetics, and combinations of these practices impact alfalfa yield and forage quality. Trials were conducted at three sites in Utah from 2020 to 2022 on young alfalfa stands (establishment and first one to three production years). Treatments included five irrigation technologies, four irrigation rates, and two …