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Asymmetric Synthesis Of Borylated Amines Via Rhodium Catalyzed Hydroboration Of Allylamine Derivatives: Surprising Role Of Counterions And Accelerators, Rukshani Wickrama Arachchilage

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

The Catalytic Asymmetric Hydroboration (CAHB) reaction is a valuable method for synthesizing chiral organoboron compounds. Nevertheless, key mechanistic details, including catalyst activation, ligand effects, and rate-determining steps, are difficult to generalize and remain not fully understood. Building on previous research from the Takacs group, this work explores acyclic N-acyl allylamines as substrates in rhodium-catalyzed hydroboration and investigates the formation of active catalysts from various rhodium precursors, the role of counterions (e.g. BF₄, BArF-), ligand-to-metal ratios, and the impact of external fluoride additives (e.g. TBAT). Hydroboration of acyclic N-acyl allylamines achieves up to 90% yield and 99 : 1 …

Host Genetic Variation And Environmental Stress Shape Microbiome Assembly And Host–Microbe–Pathogen Dynamics In Drosophila, Nitin Bansal

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

Host-associated microbiomes play central roles in host physiology, development, and susceptibility to disease, yet their composition and stability vary widely across genetic, environmental, and ecological contexts. Understanding the factors that shape microbiome structure remains a key challenge in host–microbe biology. This thesis examines how host genetic background and environmental perturbations independently influence gut microbiome composition in Drosophila, and uses mechanistic modeling to explore how microbial dynamics can affect pathogen invasion outcomes.

In Chapter 1, I investigate how mito-nuclear genetic variation influences gut microbiome structure across developmental stages and generations. Using 16S rRNA sequencing, I show that microbiome composition differs between …

Interparental Relationship Quality Reduces Parental Stress And Subsequent Family Dysfunction Across Pregnancy And Early Childhood, Rachel Clara-Beth Beck

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

In this multiple paper dissertation, I found that a higher quality interparental relationship, characterized by more emotional intimacy, support, responsiveness and better conflict management skills, plays a key role in reducing stress and its subsequent impact on family dynamics. Aims and hypotheses were tested using longitudinal data collected from mixed-sex couples during the pregnancy-postpartum transition and into early childhood. In study #1, higher quality interparental support during pregnancy was associated with lower postpartum stress which, in turn, predicted fewer parent–infant bonding impairments. In study #2, a mutually responsive orientation in the couple relationship during pregnancy interacted with intrapersonal regulatory resources …

Analysis Of Dynamic Difficulty Scaling Ai In Video Games, Tyrese W. Walker

Honors Program: Senior Projects (Public)

Video games are a popular form of interactive media and, since their inception, have become one of the largest forms of media consumed. As such, they have evolved greatly from their humble beginnings into much more complex experiences, and adjusting the difficulty level to suit the needs of the player has become common practice. While there are simple ways to do so, the best games often feature a dynamic difficulty-scaling system that adapts to the player. Classics like Resident Evil and Left 4 Dead are excellent examples of innovative dynamic scaling design. By analyzing the strongest elements of these works, …

Examining Associations Between Cognitive Factors And Behavior To Promote Culturally Responsive Teaching In Middle School Math: A Conceptual Replication Study, Ashley Struebing

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

The purpose of this research was to examine the association of middle school math teachers’ cognitive processes on their use of culturally responsive teaching (CRT) practices to promote CRT in middle school math classrooms. Specifically, a quantitative, cross-sectional research design was used to conduct a conceptual replication of Comstock et al. (2023), and to extend their research by exploring the association between teachers’ self-efficacy in teaching math and their use of CRT practices. Participants in the current study were urban and rural middle school math teachers who may or may not have been involved in a CRT professional development program, …

Hormesis In Plants: Implications For Weed Management And Crop Production, Luka Milosevic

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

Hormesis is a biphasic toxicological phenomenon in which low doses of a stressor stimulate biological performance of an organism, while higher doses inhibit it. In plants, hormesis has been documented following exposure to various environmental stressors, including herbicides, pollutants, and thermal stress. However, the physiological basis of hormesis and its implications for crop production and weed management remain poorly understood. Thus, the objective of this dissertation was to investigate hormetic responses in plants and evaluate their agronomic significance for crops and weeds using representative model species. A combination of field and controlled-environment experiments was conducted to quantify plant responses to …

Developing Best Recommendations For Aerial Application And Chemigation Of Insecticides For Western Bean Cutworm (Striacosta Albicosta Smith) Management In Corn, Andrea Rilakovic

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

Western bean cutworm, Striacosta albicosta (Smith), is a univoltine moth in North America, recognized as an economic threat to both corn (Zea mays L.) and dry bean (Phaseolus vulgaris L.). In the Midwest of the United States, S. albicosta can cause severe damage by reducing the quantity and quality of corn ears through larval feeding. Currently, options for Bacillus thuringiensis (Bt) proteins that can effectively control S. albicosta are limited, relying on only one Vip3A effective protein, while other growers use insecticide application via airplanes or center pivot irrigation systems, known as chemigation. Given the importance …

A New Subspecies Of Papilio Indra (Papilionidae) From The West Desert Of Utah, Usa, Wayne H. Whaley, Alexander A. Jason, Todd L. Stout

The Taxonomic Report of the International Lepidoptera Survey

Papilio indra bonnevillensis is a new described subspecies partly based on taxonomic rearrangement of its larval host plant reproductive phenology relative to Wasatch Range nominate P. indra. It is geographically isolated in Utah’s West Desert from populations of ssp. nevadensis to the west and ssp. calcicola to the south. In addition to phenological differences compared to these two subspecies, it merits description based on host Lomatium depauperatum which recently speciated from L. grayi, neither of which is used as host by other subspecies of P. indra. The evolution of new host L. depauperatum is …

The Intersection Between Adolescent Pregnancy, Mental Health Concerns, Stigma, And Sex Education, Madelon Cox

Honors Program: Senior Projects (Public)

This thesis discusses research from the past two decades focused on factors contributing to an increased risk of adolescent pregnancy and the lasting impact of that pregnancy. The consequences of being a pregnant adolescent can be compounded by race, gender, socioeconomic class, and access to education. Adolescent pregnancy also carries significant physical and mental health risk for the adolescent and the child. Awareness and various interventions can help pregnant adolescents or those who may be at risk for adolescent pregnancy to support them, prevent isolation, and reduce further negative mental health conditions, such as depression and anxiety.

Unl Emeriti And Retirees Association Newsletter, May 2026

UNL Emeriti and Retirees Association: Newsletters and Other Materials

University of Nebraska-Lincoln Emeriti and Retirees Association Newsletter, May 2026

Message from the ERA President, Vicki Highstreet

Welcome to new members

Recipe

Volunteer service

Funding opportunity

Wake up your well-being

Programming recaps

Celebration of life: Larry Dlugosh

Memory moments

Evaluating The Impact Of Intercropping Vegetables And Cut Flowers On Yield And Conservation Biological Control, Alliance Igiraneza

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

Specialty crops such as vegetables are some of the most susceptible to yield losses and increased management difficulty over time due to pests. One of the potential solutions to this problem, which aims at ensuring the sustainability of the sector, is using conservation biological control practices such as intercropping to increase diversity, while maintaining the economic feasibility and profitability of the system. This study was conducted to evaluate the impact of this management practice using Bell pepper (Capsicum annuum var. King Arthur) as the main crop, intercropped with flowers including zinnia (Zinnia elegans var. Benary’s Giant), sunflower ( …

Beyond The Cycle: How Menstruation Influences Gender Identity And Well-Being In Binary And Non-Binary Adults, Rin Nguyen

College of Education and Human Sciences: Dissertations, Theses, and Student Research

Approximately 1.8 billion people worldwide menstruate, including transgender and gender-diverse (TGD) people, yet their experiences remain underrepresented in research. Given that menstruation can affect gender alignment and psychological well-being, understanding its impact on TGD people is critical. Gender congruence, or alignment between one’s gender identity and expression, is a key factor influencing well-being, with research linking it to reduced depression and anxiety. Furthermore, emerging research on gender euphoria, the joy experienced when gender congruence is experienced, suggests it may serve as a protective factor for mental health and well-being. Gender euphoria has been associated with reduced psychological distress and increased …

Improving Genomic Prediction For Feed Efficiency Traits In Beef Cattle Using Microbiome As An Intermediate Omics, Egodage Bhagya Sewwandi Samarakoon

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

Feed efficiency traits, including feed conversion ratio (FCR), average daily gain (ADG), and average daily dry matter intake (ADDMI), are economically important in beef cattle production. Emerging evidence suggests that host genetics influences feed efficiency traits through the microbiome. This study evaluates the integration of microbiome data as an intermediate layer in the Neural Network Mixed Model (NNMM), which hierarchically models genotype–microbiome–phenotype relationships as a unified regulatory network to improve genomic prediction accuracy. To reduce the computational burden of NNMM, microbiome features dimension were reduced using principal component analysis (PCA) and direct feature selection of top-ranked open reading frames (ORFs) …

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 …

From Prairie To Practice: Forensic Taphonomy, Ethics, And Regional Ecology In Southeastern Nebraska, Jessica F. L. Gammage

Department of Anthropology: Theses and Student Research

Forensic taphonomy examines the postmortem processes that affect human remains within specific environmental contexts and plays a critical role in medicolegal death investigation. Despite significant advances in decomposition research, experimental studies remain geographically and environmentally uneven, limiting the transferability of postmortem interval (PMI) estimation methods across regions. The Central Great Plains are underrepresented in forensic taphonomic research despite its distinct ecological and geomorphological characteristics.

This thesis evaluates southeastern Nebraska as a specific regional setting for forensic taphonomic research by integrating ecological, pedological, and geomorphological data with current forensic literature. Tallgrass prairie vegetation, loess-derived soils, seasonal moisture variability, and dynamic fluvial …

Understanding Roma Oppression In Europe Through Humantarian Forensic Analysis, Christal L. Quinn

Department of Anthropology: Theses and Student Research

This thesis examines the marginalization of Roma people in Europe, and how humanitarian forensic practices may help Roma communities in their quest for justice and recognition. The study draws exclusively on secondary information to examine the social, political, and legal issues affecting the Roma communities, who have endured centuries of institutional discrimination, marginalization, and violence. This thesis identifies ways in which systematic oppression continues to limit Roma communities’ access to education, housing, healthcare, and legal protection through a review of relevant literature and applicable theoretical frameworks. The study also examines the relevance of forensic science, particularly its humanitarian applications, in …

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

Department of Anthropology: Theses and Student Research

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

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

Non-Destructive Automated Classification Of Human And Large Mammal Long Bone Fragments: A Deep Learning Approach Using Micro-Ct Histomorphology And Grad-Cam Interpretation, Kathleen Marie Kelley

Department of Anthropology: Theses and Student Research

This study explores the development and validation of an automated, deep learning system designed to differentiate human from large mammal long bone fragments using micro-CT imagery. A comprehensive dataset of cross-sectional µCT images was assembled from human and animal skeletal material processed at the DPAA, Nebraska. A convolutional neural network (CNN) based on a ResNet-18 architecture, utilizing transfer learning from ImageNet weights, was trained to classify µCT images as human or animal. The model achieved a mean classification accuracy of 89.85% (± 8.27%) across five sample-level cross-validation folds, with a sensitivity of 96.21% and a 95% bootstrap confidence interval of …

Roads To Antiochia Ad Cragum: Pedestrian Survey And A Least Cost Path Model Of Roman Roads In The Vicinity Of Antiochia Ad Cragum, Southern Türkiye, Alexander W. Pastor

Department of Anthropology: Theses and Student Research

Antiochia ad Cragum, a Roman site located in modern southern Türkiye, has been intensively investigated through archaeological study. However, the surrounding landscape has received less attention. This thesis addresses this gap by examining how this past settlement might have been accessed, which is an important step in gaining a better understanding of how people and resources traveled overland and how infrastructure was made to accommodate this travel. Pedestrian survey was conducted along posited western and eastern segments of a Roman-era road, finding remains consistent with but not definitively establishing this interpretation. In addition, Geographic Information Systems (GIS) was used to …

A New Electroencephalography Electrode Design For Curly And Kinky Hair Types, Elena Butler

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

Medical discrimination and implicit bias are present in both societal systems and into the design and validation of medical devices. Traditional electroencephalography (EEG) systems often fail to provide reliable physiological recordings on curly and kinky hair types (3B–4C), associated typically with Black American and others of African descent. EEG on these hair types often results in high electrode-scalp impedance, poor signal quality, and participant discomfort. Consequently, such technical biases contribute to the underrepresentation of these populations in neuroscience research and clinical diagnostics, while simultaneously limiting equitable access to EEG-based medical care.

To address this gap, a novel conductive electrode attachment …

Beyond Local Pathology: Exploring The Role Of Gut Microbiota In Chronic Low Back Pain Using An Integrated Behavioral And Microbiological Approach, Adan L. Redwine

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

Chronic low back pain (LBP) affects millions worldwide, often originating from intervertebral disc (IVD) degeneration. While the gut microbiome modulates musculoskeletal pain, prior studies of the gut-disc axis have focused entirely on structural changes. This leaves a critical gap: does the microbiome influence the experience of discogenic pain? To answer this, an integrated approach using longitudinal gut microbiome profiling, machine learning-based behavioral phenotyping, and structural disc assessments in a rat model of discogenic LBP was utilized.

Female Sprague Dawley rats underwent one of four conditions: sham surgery, IVD injury, antibiotic-mediated microbiome depletion + IVD injury, or IVD injury + treatment …

Lipid Deposition In Beef Cattle, Kyra L. Elliott

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

Both the amount and types of lipid deposition in beef cattle are key determinants of carcass value and meat quality. Amounts of intramuscular, subcutaneous, and visceral fat influence carcass grading outcomes, palatability, and composition traits that are important to beef producers as well as consumers. The objectives of this thesis were to: 1) compare beef grading camera estimates of intramuscular fat to amounts of chemically extractable lipid, 2) characterize the lipidomes of beef intramuscular fat, subcutaneous fat, and lean muscle using shotgun lipidomics, and 3) identify and characterize a novel genetic variant in cattle that may have important implications for …

Characterization Of Activity Changes In Gilts During Estrus Using The NuTrack Livestock Monitoring System, Emily P. Aquino

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

Early and accurate detection of estrus in replacement gilts is essential for reproductive success and to ensure efficient production. The objective of this study was to evaluate activity changes occurring relative to first estrus of gilts and subsequent cycles. At ~ 110 days of age, 112 gilts were randomly assigned to 14 pens and placed under continuous video monitoring until the end of the trial at ~ 200 days of age. Daily boar exposure (~ 10 minutes per day) began at ~ 122 days of age. During this period, recorded observations included vulva scores (based on swelling and redness), mounting …

Evaluation Of Maternal Bovine Appeasing Substance Administration And Feed Access Time On Finishing Cattle Performance, Behavior, And Carcass Characteristics, Carsten L. Loseke

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

Novel products and bunk management techniques may significantly influence economically relevant performance metrics of feedlot cattle. The objective of the first experiment was to evaluate maternal Bovine Appeasing Substance (mBAS) administration on performance, carcass, health, and cortisol outcomes of yearling steers. Steers (n = 1,754, initial BW = 423 kg, SD = 25 kg) were received and assigned to pens for treatment allocation. Steers received either 10 mL of the mBAS or a mineral oil placebo at initial processing and reimplant. Hair samples were collected from a subset (n = 4 steers/pen) on d 0 and d 14. …

Integrating Growth Performance And Pathogen Detection To Investigate Disease Resilience In Commercial Swine, Emmalise Hope Marie Meyer

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

Disease resilience is an important trait in commercial swine production, influencing both animal health and growth performance under natural disease challenge. The primary objective of this study was to integrate growth performance data with longitudinal pathogen detection to better understand factors contributing to disease resilience in commercial pigs. A population of 1,014 pigs across four batches was monitored from weaning through the grow-finish phase, with body weights collected to calculate average daily gain (ADG). Genome-wide association analyses were conducted using BayesC and BayesIM approaches to identify genomic regions associated with growth performance. Longitudinal pathogen surveillance was performed using pen-level oral …

Tail Biting In The Nursery: Evaluating Postural, Spatial, And Behavioral Differences Between Tail Biter And Victim Pigs, Storey L. Forster

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

This study examined behavioral differences among pigs classified as tail biters, victims, or neutral during the nursery period. A total of 192 undocked nursery pigs were assigned to eight pens and monitored for 30 days using the NUtrack system. Tail biting events were identified from video observations, and pigs contributing to the top 25% of observed tail biting activity were classified as tail biters. Based on weekly tail scoring, pigs assigned a maximum tail injury score ≥ 2 were classified as victims. All other pigs were considered neutral. A total of 700 tail biting events were observed. Thirty-eight pigs …

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 …

Factors Affecting The Efficacy Of Free Choice Vitamin & Mineral Supplementation Programs, Tanner K. Wansing

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

While free choice vitamin and mineral supplements are widely used within the cow/calf sector, large knowledge gaps exist around the proper management of those supplements. This thesis discusses two factors affecting the efficacy of supplementation. The first interest was the stability of vitamin A when stored with a common free choice mineral supplement. This research addressed a critical data gap by generating information on vitamin A stability within the beef industry, as current data are predominantly based in the swine industry. Vitamin A was discovered to be stable until 4 months of storage regardless of storage conditions, whereas after 4 …

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 …