Mitigating Nitrogen Losses: The Role Of Enhanced Efficiency Fertilizers In Sustainable Corn Production, Dipesh Giri

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Nitrogen (N) is essential for crop production, but its inefficient use often leads to environmental losses through nitrate leaching, ammonia volatilization, and nitrous oxide (N₂O) emissions. Enhanced efficiency fertilizers (EEFs), such as nitrification inhibitors (NIs) and urease inhibitors (UIs), have been developed to minimize these losses and improve nitrogen use efficiency (NUE). This research combined a multi-year field experiment and a controlled laboratory study to evaluate how dual-inhibitor fertilizers compare to conventional urea and single-inhibitor formulations in Nebraska cropping systems. The main objective was to understand how nitrogen inhibitors influence N availability, crop performance, and nitrogen losses across different environmental …

Improving Nitrogen Management And Corn Productivity Through Enhanced Efficiency Fertilizer And Cover Crop Integration In Nebraska Cropping Systems, Madhusudhan Adhikari

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Effective nitrogen (N) management is vital for sustaining corn yield and reducing environmental impacts in Nebraska cropping systems. Three field studies were conducted to evaluate the impact of 1) fertilizer type (anhydrous ammonia [AA] with nitrification inhibitor: enhanced efficiency fertilizer [EEF] or AA without EEF) and N application timing (pre-plant vs. split with side-dress UAN) on in-season soil N availability, crop response, nitrous oxide (N₂O) emissions, residual soil N and N use efficiencies (NUEs); 2) winter cover crop (CC) species and crop rotation variability on CC biomass production, N uptake, soil N dynamics, and cash crop performance in …

Extending Cover Crop Growing Window To Improve The Health Of Environmentally Sensitive Soils, Noshin Ara Tunazzina

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Sloping and sandy soils are highly susceptible to degradation. The health of these soils could be improved with cover crops (CCs). However, CC effectiveness in improving soil health mainly depends on CC biomass production, which is often low in temperate regions. The question is: how can we increase CC biomass production? Lengthening the CC growing window can be a potential strategy. This study assessed how 1) interseeded and terminated early (2-3 weeks before crop planting) CC, 2) interseeded and terminated late (at crop planting) CC, 3) drilled (after harvest) and terminated early CC, 4) drilled and terminated late CC, and …

Examining The Molecular Mechanisms Of Glucagon-Like Peptide-1 Receptor Agonists In Cancer Cell Biology, Oliver G. Sabet

Honors Scholar Theses

Glucagon-like peptide-1 receptor agonists (GLP-1RAs) are synthetic analogs of glucagon-like peptide-1 (GLP-1) used to treat obesity and diabetes by reducing blood glucose levels and appetite. While early rodent studies suggested a link between GLP-1RAs and thyroid cancer pathogenesis, evidence in humans remains inconclusive, with randomized controlled trials not supporting that link. Due to the rapid, widespread use of these drugs, concerns have expanded to other obesity-associated cancers, with conflicting findings on their role in cancer progression. With this contradictory evidence in a novel intersection of obesity medicine and oncology, this literature review aims to summarize current understandings between GLP-1-RAs and …

The Role Of Myosin L In The Survival Of Toxoplasma Gondii And The Importance Of Mlc1 For In Vitro And In Vivo Myosin F Motility, Victoria K. Yi

Honors Scholar Theses

My thesis discusses the work that I have conducted on two myosins in Toxoplasma gondii, which is an obligate intracellular parasite that has chronically infected around 10% of the American population. It causes toxoplasmosis and severe health consequences for individuals with compromised immune systems or when infections occur in utero. However, immunocompetent individuals are asymptomatic or present with subclinical symptoms. In the Heaslip lab, I investigated two myosins in the parasite: Myosin L and Myosin F. MyoL is an uncharacterized motor that localizes at the apical end of the parasite. It was shown to be important for parasite …

Identifying Cognitive, Affective, And Developmental Mechanisms Linking Threat And Deprivation With Adolescent Psychopathology, Ekaterina Sadikova, David G. Weissman, Maya L. Rosen, Elise Robinson, Liliana J. Lengua, Margaret A. Sheridan, Henning Tiemeier, Katie A. Mclaughlin

Neuroscience: Faculty Publications

Background: The mechanisms linking early-life adversity with psychopathology over the life-course are complex. In this prospective study, we collectively examined cognitive, affective, and developmental mediators previously found to individually link childhood threat and deprivation experiences to adolescent psychopathology to identify the most potent mechanisms. Methods: Data came from a community sample of 227 children (mean child age 11.5 ± 0.5 years, 48.5% female) from the Seattle metro area with recruitment designed to reflect diversity in family income. Candidate mechanisms included self-rated pubertal development and task-measured attention bias to threat, emotion regulation, theory of mind, fear learning, inhibitory control, language ability, …

Dna Gyrase Inhibition By Ni(Ii)-Schiff Base Complexes Via In Silico Molecular Docking Studies: Spectroscopic, Dft Calculations And In Vitro Pharmacological Assessment, Ikechukwu P. Ejidike, Amani Direm, Cemal Parlak, Solomon A. Olaleru, Charles O. Adetunji, Athar Ata, Et. Al.

Michigan Tech Publications

The current world's life-threatening illnesses have amplified multidrug resistance infections, bringing about immune system mayhem, thus, the quest for novel antimicrobial compounds with a broad spectrum of action. Four Ni(II) complexes, [Ni(YB)Cl]·2H₂O (C1), [Ni(YB)Br]·H₂O (C2), [Ni(YB)NO₃]·3H₂O (C3), [Ni(YB)COOCH₃]·2H₂O (C4) [HYB = 4-[(1E)-N-{2-[(Z)-(4-methoxybenzylidene)amino]ethyl}ethanimidoyl]benzene-1,3-diol], were synthesized. Analytical techniques like CHNS analysis, UV–Vis, FT-IR, molar conductance, XRD, ¹H NMR, and TGA/DTA were utilized for characterization. The calculated …

Educational Empowerment: Building Connections Through Interventions, Melanie V. Partida

Capstone Projects and Master's Theses

This capstone project explores the intersection of substance use disorder (SUD) recovery and educational empowerment, focusing on the clients and peer supporters at Janus of Santa Cruz. The initiative developed an educational support model to enhance recovery through access to adult education, vocational training, and reliable study environments. Utilizing structured surveys, the project identified the educational barriers faced by peer supporters and clients, such as limited access to internet connectivity, mental health challenges, and a lack of awareness regarding local resources. In response, this project included the creation of a comprehensive educational resource directory and a Peer Mentorship Model, enabling …

Leveraging Predictive Analytics To Improve Prognostic Models For Uterine Cancer, Arnav Joshi

Open Access Theses & Dissertations

Uterine Corpus Endometrial Carcinoma (UCEC) presents notable disparities in incidence and outcomes across racial groups, warranting deeper investigation through transcriptomic and predictive modeling approaches. This thesis presents a comprehensive transcriptomic analysis of RNA-Seq data from 177 individuals, comprising both tumor and control samples, specifically from the UCEC_CN_High molecular subtype. The cohort was stratified by race, focusing on differences between Black and White individuals to explore race-associated gene expression patterns. To uncover genes with prognostic significance, LASSO (Least Absolute Shrinkage and Selection Operator) regression was applied for feature selection, identifying a subset of genes most strongly associated with overall survival. These …

Clinicogenomic Insights For Prostate Cancer Progression, Kelvin Ofori-Minta

Open Access Theses & Dissertations

Prostate cancer (PrCa) remains a critical challenge in precision oncology due to several reasons including its apparent heterogenous condition, recurrence following treatment and rapid progressive forms. Therefore, identifying patients at risk of progression is essential to fast-track therapeutic decisions and improve outcomes. Despite recent advances in genomic and molecular profiling, conventional PrCa risk assessment tools heavily rely on a few clinical parameters, neglecting the prognostic potential of genomic biomarkers in the presence of clinical biomarkers. This study presents a computational pipeline to harmonize and evaluate the prognostic value of clinicogenomic profiles of patients in modelling progression free survival (PFS). PFS, …

Multiscale Integration Of Receptor-Ligand Dynamics Into Discrete And Continuous Tumor Growth Models With Application To Tyrosine Kinase Inhibitor Treatment, Romasa Qasim

Open Access Theses & Dissertations

The epidermal growth factor (EGF) receptor cascade plays a crucial role in the survival and proliferation of tumor cells. Tyrosine kinase inhibitors (TKIs) are a class of drugs that inhibit epidermal growth factor receptors (EGFRs), thereby preventing the downstream signal transduction. Despite their importance, models that link spatial receptor dynamics to tumor growth remain scarce. Further, TKIs act through selective mechanisms, inhibiting active, inactive, or all receptor states, which poses a challenge to traditional modeling approaches.

We propose to numerically study two mathematical models incorporating receptor-dynamics into cancer models to describe the impact of EGFR overexpression and TKIs. The first …

Pathways Of Nitrogen Loss After Fertilization In Dryland Ecosystems, Fidel Manuel Renteria

Open Access Theses & Dissertations

Dryland ecosystems cover approximately 41% of the Earth’s terrestrial surface, and are characterized by limited moisture, nutrient-poor soils, and pulsed precipitation regimes that collectively constrain nutrient cycling. Although nitrogen (N) is often assumed to be a primary limiting nutrient in these environments, fertilization studies frequently reveal minimal biotic response to added N—a pattern known as the "dryland nitrogen paradox." This paradox has been attributed to rapid nitrogen loss via gaseous emissions and leaching, exacerbated by interactions with water and phosphorus (P) availability. To investigate these loss pathways, we conducted a field experiment at the Jornada Experimental Range in the northern …

Direct Synthesis Of Cerium Oxide Nanoparticles In Reducing Sugars: Enhanced Ce3+ Surface Density For Biological Application, Balaashwin Babu, Elayaraja Kolanthai, Craig J. Neal, Samarah V. Harb, Udit Kumar, Yifei Fu, Sudipta Seal

Rowan-Virtua Research Day

Cerium oxide nanoparticles (CNPs) are recognized for their ability to scavenge reactive oxygen species (ROS), making them promising candidates for mitigating oxidative damage in biomedical applications. However, many conventional synthesis methods limit the formation of Ce³⁺ states, which are critical for this antioxidant function. Building upon previous findings that glucose can promote Ce³⁺ formation, this study investigates the broader impact of both reducing (glucose, fructose, galactose) and non-reducing (dextran, sucrose, cyclodextrin) natural sugars on CNP synthesis. CNPs were synthesized in the presence of these sugars, and the surface densities of Ce³⁺ were measured. Results showed that reducing sugars significantly increased …

Biophysical Characterization Of Thermophilic Branched-Chain Amino Acid Periplasmic Binding Protein From Thermotoga Maritima, Sky Marsicano

Honors Theses

Members of the periplasmic binding protein superfamily are involved in the selective passage of ligands through bacterial cell membranes. The hyperthermophilic eubacterium Thermotoga maritima encodes a putative periplasmic branched chain amino acid binding protein (TM1135). The gene was cloned into pET21a(+), overexpressed in Escherichia coli, purified using Ni-NTA chromatography, and confirmed with SDS-PAGE and MALDI mass spectrometry. Biophysical characterization of the protein was performed with fluorescence spectroscopy, absorbance spectroscopy, and circular dichroism experiments to investigate structural stability and ligand binding ability. Using circular dichroism, we demonstrate that TM1135 binds to the branched chain amino acids isoleucine, leucine, and valine, and …

Evaluation Of Fecal Egg Counts (Fec) As A Viable Means To Estimate Ascaridia Galli, Heterakis Gallinarum And Capillaria Obsignata Burdens In Laying Hens, Alexander H. Moss

Animal Science Undergraduate Honors Theses

The control of gastrointestinal helminths, specifically Ascaridia galli, Heterakis gallinarum, and Capillaria obsignata, is a critical component of poultry health management, particularly in free-range and organic farming systems. Methods of estimating parasite burdens, such as post-mortem examinations, are not feasible for large-scale commercial operations due to their invasiveness and time requirements. This study aimed to evaluate the use of fecal egg counts (FEC) as a non-invasive and efficient method for estimating the worm burdens of these parasites in laying hens. A flock of 12 brown egg laying, spent, hens were individually penned on concrete. Fecal samples (both cecal and intestinal) …

Acetylcholine Release In The Dorsal Lateral Straitum During Social Approach Task, Taylor Good, Oyku Dinckol, Noah Wenger, Jake Caselli, Munir Gunes Kutlu

Rowan-Virtua Research Day

Nicotine Decreases ACh Release in the DS leading to a Serenic Effect during Social Approach Task

Acetylcholine (ACh) regulates attention, learning, and stress responses (Benarroch E. E., 2012). The dorsal striatum (DS), essential for stimulus-response learning, is also linked to anxiety and compulsivity (Casado-Sainz et al., 2021). We used behavioral pharmacology and in vivo fiber photometry to study ACh responses during social approach tasks in the dorsal striatum. Male and female C57BL/6J mice underwent stereotaxic surgeries to inject a fluorescent ACh sensor (ACh.Sn.Fr) and implant fiber optic cannulas in the DS. Using in vivo fiber photometry, we tracked ACh release …

Hypoxia Induced Ribosomal Rna Fragmentation Mediated By Rnase L, Vanessa Kristina Pizutelli, Dimitri G Pestov

Rowan-Virtua Research Day

Ischemic injury contributes to a range of global pathologies. Ischemia/Reperfusion Injury (IRI) is a paradoxical phenomenon that involves an initial restriction of blood flow followed by a sudden restoration of perfusion. This type of injury takes place in conditions such as myocardial infarction, acute kidney disease, and ischemic stroke and often leads to cellular death. Additionally, IRI exacerbates post-surgical outcomes and plays a role in graft dysfunction and transplant rejection. Despite efforts to develop therapies targeting known IRI pathways, clinical trials have largely been unsuccessful, underscoring the need for alternative mechanisms and biomarkers associated with IRI-induced apoptosis. Reactive oxygen species …

Modulation Of Opioid Receptor Expression In The Ventral Tegmental Area Following Stress Exposure In Rats, Maya Patel, John Tkaczynski, Jordan Riser, Nicole Shellenbarger, Jin Park, Daniel Manvich, Daniel J. Chandler

Rowan-Virtua Research Day

Background: The ventral tegmental area (VTA) contains dopamine-producing neurons projecting to various brain regions. VTA dysfunction is linked to addiction and depression. Delta opioid receptor upregulation relates to chronic pain, inflammation, cancer, and early adversity. Kappa receptors in the VTA influence stress, drug-seeking, mood, and reward. Notably, chronic substance abuse upregulates the κ-receptor/dynorphin system, and the opioid system regulates social interaction needs.

Hypothesis: Stress will upregulate opioid receptors.

Methods: We compared group-housed and individually-housed rats using stress tests, analyzing behavior and quantifying VTA opioid receptor expression.

Results: Social isolation upregulated delta and kappa opioid receptors in …

Investigating The Effects Of Prenatal E-Cigarette Exposure On Postnatal Liver Histology, Emma Mcclellan

College of Arts & Sciences Senior Theses

The electronic cigarette (e-cigarette) entered the American market in the mid-2000s and quickly became popular. This product poses a significant threat to youth with 1.63 million students reporting use in 2024. Adverse health effects to different organs are well known. The liver is less studied, and despite its role in detoxification of e-cigarette chemicals, is a target of injury. Unlike the known effects of cigarettes and nicotine on the liver from adult or prenatal exposure, effects of prenatal exposure to e-cigarettes on liver remain to be defined. The current study investigated the effects of prenatal exposure of e-cigarettes on liver …

Effects Of Cadmium And Diet On Metal Accumulation And Kidney Cell Death Pathways., Justin Xu

College of Arts & Sciences Senior Theses

Cadmium (Cd) is a non-biodegradable environmental toxin and accumulates in the body with an estimated half-life of 30-45 years. Humans can be exposed to Cd through diet, drinking water, tobacco smoking, and industrial pollution. Cd can especially accumulate in the kidney due to the release of Cd from protein-metal complexes when filtering blood in the tubules causing oxidative stress and inducing kidney injury. Obesity is another risk factor for kidney disease therefore we examined the dual effects of Cd and obesity on the accumulation of essential metals in mouse kidneys. Starting in utero and continuing until 24 weeks postweaning, male/female …

Understanding The Properties Of Repair Protein P26 For Dry-State Preservation Of Biological Materials., Hannah Skaggs

College of Arts & Sciences Senior Theses

The preservation of complex biological materials in the frozen state has been well established and plays a critical role in the advancement of clinical applications and the pharmaceutical industry. Cryopreservation of complex biological materials has several clinical applications, including vaccine preservation, bone marrow transplants, cell therapeutics, and increasing the shelf life of red blood cells (RBCs) for transfusion. However, many challenges are present, including the use of toxic protective agents and the financial burden of maintaining extremely low temperatures between 193.15 and – 77.6 K (Parihar, Kumar et al. 2023). Lyophilization, or freeze-drying, presents an opportunity to mitigate such challenges. …

Recombinant Expression And Purification Of Porphyromonas Gingivalis Tyrosine Kinase 1 In Escherichia Coli., Laura K. Hanna

College of Arts & Sciences Senior Theses

The goal of this study was to optimize the expression and purification of Porphyromonas gingivalis Tyrosine Kinase 1 (Ptk1) in recombinant Escherichia coli containing the plasmids Gro_ESL and Ptk1, with a His₆ tag_, to obtain a highly pure protein sample. Various experimental conditions were tested to determine the most effective parameters for protein expression and purification, including adjustments in induction timing, buffer composition, and purification techniques.

Optimal protein expression was achieved when cells were induced at an optical density (OD) of 0.3 to 0.4. β-D-1-thiogalactopyranoside (IPTG), which activates the lac operon, was used to induce Ptk1 expression. A …

Sacred Grounds: A Risk Assessment Framework Developed For Historic African American Cemeteries Threatened By Sea Level Rise In Georgetown, Sc, Jocelyn Patterson

All Theses

ABSTRACT

This study acknowledges historic African American cemeteries as vital cultural and historical landmarks that preserve the stories and traditions of often overlooked communities. However, coastal cemeteries, particularly in Georgetown, South Carolina, face increasing environmental threats. These burial sites risk severe damage or complete loss as climate change accelerates from sea level rise, flooding, storm surges, neglect, development pressure, and land development.

This research develops and considers a risk assessment framework to address the risks of cemeteries proximity to water, elevation, flood risk, and cultural significance. The research employs Geographic Information Systems (GIS) mapping, historical records, and site analysis to …

Behavior Change: Actions To Restore Piedmont Prairie And Adopt Sustainable Behavior, Kacey Marie Kaibery

All Theses

Restoration of an ecosystem or adoption of sustainable behavior could benefit the environment. Valuable ecosystem services, like water filtration and habitat for pollinators, inspire investigation into the restoration of grasslands, like Piedmont prairies. This research endeavors to determine the impact of disturbance type (tilling, herbicide, mowing, fire, control with seed or no seed). The second-year aboveground biomass was harvested, identified, counted, and weighed to understand plant species’ response after the application of the disturbance. Target species and plant community diversity did not significantly vary between disturbance types. Planting methods (hand dispersal, drill, one-month and six-month transplanting) on Asclepias tuberosa establishment …

Dual-Task Cost Of Gait Measures In Individuals With And Without Parkinson's Disease, Addison G. Miller

Health, Human Performance and Recreation Undergraduate Honors Theses

Parkinson’s disease (PD), estimated to affect over one million people by 2030, is a neurodegenerative disease that damages the dopaminergic neurons located in the brain. Losing these neurons cause individuals with PD to experience impairments in basic motor and cognitive functions. Symptoms of PD often include bodily shaking, muscle stiffness, and abnormalities in gait and posture. Individuals with PD can also experience impairment when walking and performing secondary tasks, such as walking while talking, known as dual tasking. Dual tasking can lead to increased risk of falling or losing balance, as well as the inability to move freely while carrying …

Characterization Of 3d Printed Microdialysis Probes For Solute Recovery And Non-Specific Adsorption, Bailey N. Scoggins

Chemistry & Biochemistry Undergraduate Honors Theses

Microdialysis is an important sampling technique that has uses in a wide range of disciplines, such as neuroscience and pharmacokinetics. 3D printing aims to address adaptability and customization issues that are present in standard “off-the-shelf” microdialysis probes. This work aims to lay the groundwork for characterizing a 3D printed microdialysis probe designed at the University of Arkansas. One experiment involved measuring solute recovery of caffeine as a function of flow rate of a standard CMA 11 probe to assess its membrane performance. The other goal was to learn about non-specific adsorption tendencies of enzymes (i.e., to what degree proteins stick …

Maximizing Crop Production And Profitability Through Double Cropping Corn And Soybean Systems In South Carolina, Bennett Harrelson

All Dissertations

Profitability is critical for farm sustainability, efficiency, and longevity. Over the last decade, corn and soybean commodity prices have fluctuated considerably, and more recently, extreme increases in input prices have narrowed profit margins. Non-traditional cropping systems that can boost profit are becoming of interest to farmers in South Carolina, specifically double cropping soybean behind corn. In this scenario, corn is harvested at high moisture contents and followed by ultra-late planted soybean. However, prior research related to the agronomic production practices of double cropping corn and soybean is minimal. To develop best management practices for growers interested in double cropping corn …

Stromal Cells In The Small Intestine: Physiology, Localization, Function, And Alterations Induced By Chronic Arsenic Exposure, Scott Ventrello

All Dissertations

Arsenic is a prevalent toxicant found to affect around 94 to 240 million individuals in over fifty countries who are exposed to levels above the EPA and WHO standard of 10 ppb. As one of WHO’s top ten chemicals of public health concern, it is linked to several chronic diseases including diabetes, obesity, cancers, and inflammatory bowel diseases. Arsenic increases inflammation and disrupts the intestinal barrier in the small intestine and colon. Further, previous studies found that arsenic decreased secretory cell lineage and stromal cell gene expression markers in the small intestine. Thus, our goal was to investigate arsenic’s effect …

Variations In Sensory And Emotional Responses To Gluten-Containing And Gluten-Free Cookie Products Under Blind And Labeled Conditions, Eniola Ola, Han-Seok Seo

Food Science Faculty Publications and Presentations

The gluten-free food market is expanding rapidly. However, consumer acceptance and emotional responses to gluten-free food, especially commercially available products, have received relatively underexplored. This study aimed to determine how consumer perceptions, acceptance, and emotional responses differ between gluten-containing (C) and gluten-free (F) chocolate chip cookies from three brands under both blind and labeled conditions. In the labeled condition, 84 participants without celiac disease evaluated 3 F cookies labeled "gluten-free" and 3 C cookies presented without claims on a plain white card. In the blind condition, they tested the six cookies without labels. Participants provided hedonic ratings, Just-About-Right (JAR) ratings, …

Morphology Of Smallmouth Bass (Micropterus Dolomieu) In Arkansas, Robert Laroche

Biological Sciences Undergraduate Honors Theses

The Smallmouth Bass, Micropterus dolomieu, is one of the most important game fishes in Arkansas. Three distinct lineages are recognized from different river basins: the Northern, Neosho, and Ouachita Smallmouth Bass. Understanding the biodiversity within this species complex inhabiting different water bodies in Arkansas is important for effective management of the fisheries resource and to guide conservation efforts. But current data on distribution of distinct forms are insufficient to guide management. The primary goals of the study presented here was to quantify morphological characteristics to identify distinct lineages of Smallmouth Bass, and to determine their specific locations within Arkansas streams …