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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 …

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 …

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

Honors Theses

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

Mechanisms Of Synergy Between Nanosecond Pulsed Electric Field (Nspef) And Cold Atmospheric Pressure Plasma Discharge (Cap) In Pancreatic Cancer: The Role Of Ros-Mediated Oxidative Stress And Apoptosis, Zobia Minhas

Biomedical Sciences Theses & Dissertations

Pancreatic ductal adenocarcinoma is a highly lethal malignancy characterized by poor prognosis and resistance to conventional therapies. Novel treatment strategies are needed to overcome this resistance. Non-thermal physical modalities, including nanosecond pulsed electric field (nsPEF) and cold atmospheric pressure plasma discharge (CAP), have emerged as potential anticancer approaches; however, the mechanisms underlying their combined effects remain unclear.

This study evaluated whether nsPEF enhances CAP-induced cytotoxicity and investigated the associated molecular mechanisms using the murine Pan02 pancreatic cancer cell line. Cell viability was assessed by WST-1 metabolic activity assays and electric cell–substrate impedance sensing (ECIS). Intracellular reactive oxygen species (ROS) were …

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 …

Sensing Rna’S Conformation With A Solid-State Nanopore Device At Various Ph And Temperature, Haopeng Li

Graduate Theses and Dissertations

This study uses solid-state nanopore technology to investigate the stability and dynamics of RNA molecules under thermal stress and pH fluctuations. Two distinct mRNA samples were analyzed: (1) heat shock protein (HSP)-encoding mRNA extracted from Sulfolobus solfataricus P2, a thermophilic archaeon inhabiting extreme environments such as geothermal sulfuric hot springs (pH < 4, temperature range: 65–90°C), and (2) total RNA extracted from White Leghorn chickens, which thrive under standard physiological conditions. ΦX174 virion single-stranded DNA (ssDNA) were included as a comparative reference. Nanopores, fabricated in silicon nitride membranes, were used to electrically characterize the structural properties of individual RNA molecules in solution, close to their native environments. The nanopore membrane separates two chambers containing salt buffer solution, where ionic current is the primary measurement parameter. When a voltage bias is applied across the membrane, ion flow and an ionic current can be measured. Charged RNA molecules driven translocation through the nanopore induces pore resistance changes, resulting in detectable current blockade events. Variations in these events provide insights into RNA secondary structure and conformational dynamics. By systematically altering pH and temperature, this study elucidates the effects of environmental stressors on RNA stability and structural integrity. The findings reveal distinct responses between thermophilic HSP-encoding mRNA and mesophilic RNA, underscoring the adaptive mechanisms of thermophilic RNA under extreme conditions. These results contribute to a better understanding of RNA behavior under stress and establish a foundation for future applications in RNA-based diagnostics and biotechnology development.

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

Honors Theses

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

Contrasting Roles Of Downed Wood And Leaf Litter In Structuring Aphaenogaster Ants And Other Forest-Floor Arthropod Communities, Danielle E. Dolan

Great Lakes Center Masters Theses

Forest floors are dynamic and spatially heterogenous landscapes characterized by differing amounts of light, temperature, and moisture. Bounded substrates, like downed wood and leaf litter, add further complexity to this landscape. Specifically, downed wood is noted for its ability to retain a higher moisture level than the surrounding environment, and as such can serve as an ideal microhabitat for desiccation intolerant organisms (e.g., salamanders and eusocial insects). Here, I attempt to disentangle the relationship between forest floor arthropods and microhabitat selection (i.e., downed wood vs leaf litter) on a northeastern forest floor. The ant, Aphaenogaster picea, was chosen as my …

Carcass Mass And Cooling Dynamics As Determinants Of Beef Color, Tenderness, And Dark-Cutting Risk, Grace C. Johnson

Department of Animal Science: Dissertations, Theses, and Student Research

Discoloration in beef has important implications to the beef industry. Dark-cutting (DC) beef remains one of the most economically significant color defects; however, industry prevalence has only marginally declined (≈ 0.1%) despite mitigation efforts. This lack of improvement largely stems from research focused on pre-harvest stress and glycogen depletion leading to dark, firm, and dry (DFD) beef. However, not all darkcutting beef originates from DFD phenotypes. Atypical dark-cutting (ATDC) phenotypes have recently been observed and do not exhibit the classic metabolic indicators of DFD. This trend coincides with steadily increasing carcass weights in the beef industry and raises the possibility …

Monitoring Biodiversity Growth In An Oyster Reef Restoration: Understanding How Oyster Reef Life Cycle May Impact Biodiversity., Gabriel A. Roses

Theses and Dissertations

Oyster reefs are vital to marine ecosystem health, improving water quality and providing food and habitat for diverse species. We assessed biodiversity changes for a proposed oyster reef restoration site to help guide management, future assessment, and deepen understanding of how oyster reefs function and their ecosystems dynamics.

Bugs, Birds, Blue: Queer Ecologies Of Embodiment, Kinship, And Survival, Celeste B. Newcomb

Theses and Dissertations

bugs, birds, blue is a multi-channel audiovisual installation that examines queer ecology as a framework for understanding transgender embodiment, kinship, and survival amid environmental crisis and ongoing political attacks on trans life (Mortimer-Sandilands and Erickson). Through sculpture, projection, sound, reflective surfaces, and biological imagery, the installation places human bodily matter alongside microbial and aquatic life forms to challenge narratives that frame trans existence as unnatural, recent, or isolated. Instead, the work proposes transness as relational, adaptive, and deeply entangled with broader ecological systems. The installation is composed of two interconnected environments. On one side of the space, three aquariums rest …

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 …

Application Of High-Pressure Processing To Improve The Color Of Dark Beef, Kara Ann Reynolds

Department of Animal Science: Dissertations, Theses, and Student Research

Deviation of beef from the bright cherry-red color preferred by consumers is often discounted or discarded at retail, resulting in substantial annual economic loss to the beef industry. One such deviation is dark cutting beef, which is characterized by a darker lean appearance that is undesirable to consumers and often rejected. Similarly, beef from mature cattle tends to exhibit a darker surface color, which can also reduce consumer acceptability. High-Pressure processing (HPP) has been investigated as a strategy to improve the color of dark cutting beef. Previous studies have focused on identifying pressure levels and holding times that optimize color …

Preclinical Animal Modeling To Investigate Redox-Mediated Molecular Dysfunction In Traumatic Brain Injury, Brandon Z. Mcdonald

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

Impacts associated with traumatic brain injury (TBI) induce a multitude of neurological morbidities mediated by a spread of biochemical dysfunction. Redox stress is a significant contributor to TBI pathophysiology and several redox stress markers have substantial evidence to support their role in diagnosing preclinical and clinical TBI. However, there is a critical need to verify their translational utility through correlations with behavioral, imaging, and molecular modalities. In chapter two, we examined the therapeutic efficacy of an antioxidant treatment (NPC3) using a controlled cortical impact (CCI) mouse model of TBI. NPC3 alleviated glial expression and reactivity while influencing the expression of …

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 …

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 …

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, …

Precision To Protein: Comparative Characterization Of Printability, Physicochemical, And Nutritional Properties Of Cricket, Pea, And Whey Proteins In 3d-Printed Nutrition Bars, Sophia Hinkebein

Food Science Undergraduate Honors Theses

Protein is a priority nutrient in the American diet, being fueled by the demands of weight loss drugs, diet culture, and new dietary guidelines. However, meeting these elevated protein goals sustainably requires diversifying beyond standard sources like whey protein isolate. 3D printing offers an opportunity to present a variety of protein sources in a palatable, customized, and consumer-acceptable format. In this study, 3 protein sources (cricket, whey, and pea), were optimized within food inks for 3D printing. Optimization involved different hydration levels, with whey requiring 7 grams of added water, cricket 22 grams, and pea the most at 47 grams. …

Gaining Mussel: Evaluating Reintroduction Success Of Native Freshwater Mussels In Nebraska And Eastern Wyoming, Travis A. Moore

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

Freshwater mussels are one of the most imperiled groups of organisms in North America, with over two-thirds of species considered threatened, endangered, or of special concern. These long-lived bivalves are essential to stream ecosystems, acting as filter feeders that improve water quality and as indicators of aquatic health. In Nebraska and Wyoming, native mussel populations have declined sharply due to habitat modification, pollution, and reduced connectivity. Two species of particular concern are the Plain Pocketbook Lampsilis cardium, listed as Tier I at-risk in Nebraska, and the Fatmucket Lampsilis siliquoidea, a Tier II at-risk species. In response, state agencies …

The Development Of A Crispr-Based Calibrated Functional Assay For Classifying Pathogenicity Of Msh2 And Msh6 Variants In Lynch Syndrome, Olivia N. Amodeo

Honors Scholar Theses

Lynch syndrome is a hereditary disease caused by the inheritance of a mismatch repair gene variant. Individuals with this condition are predisposed to cancer development, most commonly colorectal cancer. Current guidelines for variant classification are based on numerous evidence categories, including functional evidence. However, many novel clinical variants are not well characterized, and evidence is difficult to obtain if functional assays are not calibrated.

To address this, our lab created a calibrated functional assay that calculates an odds of pathogenicity score for MSH2 and MSH6 gene variants that can be used as evidence for classifying variants of uncertain significance. This …

Reversible, Light-Controlled Inhibition Of Stim1-Mediated Calcium Signaling Using Photoswitchable Ml-9 Derivatives In Jurkat-Lucia Nfat Reporter T Cells, José L. Matute Gálvez

Honors Scholar Theses

Store-operated calcium entry (SOCE) through calcium release-activated

calcium (CRAC) channels is the dominant pathway for sustained Ca2+ influx in

non-excitable cells and is essential for T cell activation, driving downstream

signaling through the calcineurin-NFAT transcriptional axis. Dysregulation of

SOCE produces multi-systemic disease phenotypes, establishing that precise,

spatiotemporally controlled modulation of this pathway is a fundamental

therapeutic requirement. ML-9 is one of the only characterized small molecules

capable of targeting SOCE upstream at the level of STIM1 localization, but lacks

the selectivity, pharmacokinetic properties, and spatiotemporal control necessary

for therapeutic development.

This work describes the design, synthesis, and biological evaluation of …

Tips For Health Care Practitioners: A Guide For Adolescent Obesity, Regina Santana

Electronic Theses, Projects, and Dissertations

Adolescent obesity continues to be a significant public health concern that is associated with long term physical consequences. The purpose of this project was to develop an evidence based, user friendly guidebook that supports healthcare professionals in the education of adolescents with obesity and their families. A structured literature review development process was used to inform the current development of the guidebook. The guidebook includes components of obesity management such as nutrition and physical activity recommendations. The validity of the content was established through the evaluation of five healthcare professionals that include registered dietitians and licensed therapists. The guidebook was …

Assessment Of Super Absorbent Polymer In Soybean Cultivation Under Variable Irrigation Conditions In Nebraska, Ankit Chandra, Abia Katimbo, Ronaldo Marchezan, Martha Nabaggala

Department of Agricultural and Biological Systems Engineering: Presentations and White Papers

Water limitation is a primary constraint to soybean productivity in both irrigated and rainfed systems. Soil-applied superabsorbent polymers (SAPs) have been proposed as a strategy to buffer crops against episodic drought stress; however, their physiological and agronomic performance under varying irrigation regimes remains insufficiently quantified. Here, we evaluate three biodegradable polymer formulations: broader granules (BB), original granules (OG), and powder (PWR) applied at low (17.7 lb/ac) and high (120 lb/ac) rates under full (100% ET), reduced (50% ET), and no irrigation conditions in western Nebraska. Polymer application had negligible effects under full irrigation, with yields comparable to untreated controls. Under …

Can Carpobrotus Edulis Cause Significant Changes To The Soil Microbiome?, Samantha J. Cowan

Electronic Theses, Projects, and Dissertations

Invasive species cause significant damage to ecosystem biodiversity and can cost billions of dollars to restore native species (Van der Wal et al, 2008; Diagne et al., 2021).  In certain instances, even if the invasive species are removed, they can leave legacy effects on the environment that make restoration more challenging (Conser and Connor, 2008; Elgersma et al., 2011). Carpobrotus edulis is an invasive species of plant that is known to cause changes to its environment such as affecting the soil nitrogen cycle and the pH, potentially leading to persistent changes in the soil microbiome and causing native species to …

Identification, Pathogenicity, And Fungicide Sensitivity Of Itersonilia Perplexans Associated With Petal Spot Of Gerbera Cut Flowers In Colombia, Matheus Beger

All Theses

Petal diseases significantly affect gerbera cut flower production, as minor visual damage renders flowers unmarketable. Among those pathogens causing petal spots, Itersonilia perplexans affects some Asteraceae plants. However, this pathogen's impact on Colombian gerbera remains poorly studied. This study was designed to fill four gaps: molecular identification of Colombian isolates, confirmation of pathogenicity, standardized culture media, and fungicide sensitivity data. Four objectives were pursued: (i) isolate and identify the causal agent through sequencing the Internal Transcribed Spacer, Small Subunit and Large Subunit from the rDNA; (ii) evaluate pathogenicity on detached gerbera petals; (iii) identify optimal culture media for I. perplexans …

Wrky Transcription Factors: Integral Regulators Of Defence Responses To Biotic Stress In Crops, Dongjiao Wang, Ruize Zhang, Wenhui Zou, Yuanyuan Zhang, Wanying Zhao, Tingting Sun, Qibin Wu, Zheng Qing Fu, Youxiong Que

Faculty Publications

Crops are continually challenged by biotic stresses, including fungal, bacterial and viral pathogens and insect pests, which cause substantial yield and quality losses worldwide. WRKY transcription factors constitute a plant-specific and functionally diverse family that is central to immune regulation. Recent advances in genomic resources and multi-omics approaches have accelerated the identification and functional characterisation of WRKYs in crops. This review summarises the structural features and classification of WRKY genes and their genome-wide distribution across crop species. It also synthesises WRKY-centred regulatory modules that mediate resistance to major classes of biotic stress. In antifungal defence, WRKYs reinforce pattern- and effector-triggered …

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 …

Effects Of M6a Dna Methylation By Bacterial Methyltransferase In Colorectal Cancer, Fabian Alejandro Mendoza Galvan

Dissertations and Theses (Open Access)

Effects of m6A DNA methylation by bacterial methyltransferase in colorectal cancer Fabian Alejandro Mendoza Galvan Advisory Professor: Angela H. Ting, Ph.D. Fusobacterium nucleatum animalis (Fna) is found in the human oral cavity and gut. A distinct clade of Fna is primarily enriched in the tumor microenvironment (TME) and within colorectal cancer (CRC) cells. This clade DNA methylation pattern is primarily catalyzed by a cell-cycle regulated methyltransferase (CcrM) ortholog, M.FnI, that targets the GANTC sequence motif through methyl-6-Adenine (m6A) DNA methylation. We hypothesized that M.FnI enzyme can induce m6A methylation abnormalities in CRC cells to promote cancer progression. Evidence for endogenous …

Refining Treatment Thresholds Of Insect Pests In South Carolina Soybeans Using Simulated Injury And Natural Populations, Adam Whitfield

All Dissertations

Insect pests are a major limiting factor to profitable soybean, Glycine max (L.) Merr., production in South Carolina, yet current economic thresholds are largely based on historical data and may not reflect modern cultivars, production practices, or input costs. Key insect pests in South Carolina can be categorized into three major feeding groups: defoliators, stem feeders, and pod feeders. Defoliating insects include, but are not limited to, soybean looper, Chrysodeixis includens (Walker); velvetbean caterpillar, Anticarsia gemmatalis (Hubner); green cloverworm, Hypena scabra (Fabricius); grasshoppers; and numerous species of beetles. Stem feeders include, but are not limited to, kudzu bug, Megacopta cribraria …