Digital Commons Network^™

Development And Evaluation Of Supported Ionic Liquid Membrane And Porphyrin Frameworks For Carbon Capture Separation, Sarang Ismail

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

The global urgency to mitigate anthropogenic CO₂ emissions has intensified the pursuit of energy-efficient separation technologies. Supported Ionic Liquid Membranes (SILMs) have emerged as promising candidates for CO₂ capture due to their tunable solubility-selectivity and low energy requirements. However, challenges such as mechanical instability, limited scalability, and trade-offs in transport performance have impeded their widespread adoption.

This thesis explores a systematic approach to designing and optimizing SILMs for enhanced CO₂ separation by tailoring polymer–ionic liquid interactions, processing conditions, and material architectures. A comprehensive set of studies were conducted using poly(vinylidene fluoride) (PVDF) with varying molecular weights, different grades of PEBAX®, …

How Beliefs Shape What We Consider When Choosing What To Eat, Christopher Gustafson

Cornhusker Economics

What determines which foods we consider? One factor, certainly, is what we like to eat, and if liking what we eat were the sole relevant outcome of food consumption, there would be little to say about incomplete consideration. However, diet quality has important, well-documented effects on health outcomes (as well as other important considerations, such as differential environmental impact). Close to 75 percent of American adults are overweight or obese, which increases the likelihood that the individual will experience one or more serious non-communicable diseases. A food’s healthiness is an important consideration for many people when making food choices, but, …

Investigating The Impact Of Agent Openness On Planning In Multi-Agent Systems, Bala Subramanyam Duggirala

School of Computing: Dissertations, Theses, and Student Research

Multi-agent systems (MAS) possess significant potential for modeling real-world scenarios requiring coordinated actions (like wildfire fighting or ridesharing) among autonomous entities or agents (e.g., wildfire fighting agents) in complex, dynamic environments. Effective decision-theoretic planning (where each agent must carefully consider both the immediate and the future situations or states, and coordinate with the other agents (neighbors) to evaluate what needs to be done at present) within MAS, especially multiagent planning, where the planning agent directly models its neighbors in order to estimate their optimal actions, is critical, yet challenged by factors like partial observability, openness, and diverse agent types with …

Zambia's Poor Septic Waste Management: A Disaster In Waiting, Andrew Mwape

School of Natural Resources: Faculty Publications

In the shadows of Zambia’s rapidly growing urban and peri-urban communities lies an invisible but mounting threat, the mismanagement of septic waste. While national dialogue often focuses on economic development, climate change, or energy, the sanitation crisis receives little public attention, yet it poses an equally severe risk to public health, environmental integrity, and sustainable urbanization. Zambia’s poor septic waste management, if left unaddressed, is a disaster in waiting.

Septic waste refers to the wastewater and solid waste that flows from toilets, sinks, and other domestic plumbing fixtures into on-site sanitation systems such as septic tanks or pit latrines. This …

Veterinary Drug Residue Regulations In Major U.S. Export Markets, Elliott James Dennis, Akinbode Okunola

Cornhusker Economics

Trade agreements shape the global agricultural trade landscape, encompassing both tariff and non-tariff measures. Among the latter, sanitary and phytosanitary (SPS) measures such as maximum residue limits (MRLs) are gaining attention. As trade tensions escalate, there is growing concern that countries could use SPS measures as a tool of retaliation in international agricultural markets, as they are often a focal point in trade negotiations (Disdier and Marette, 2010; Disdier and van Tongeren 2010; Grant et al., 2015).

Geophysical Tools For Agricultural Management: Trends, Challenges, And Opportunities, Sophia Becker, Trenton Franz, Yufeng Ge, Joe Luck, Derek M. Heeren

School of Natural Resources: Faculty Publications

Agrogeophysics is a convergence of proximal soil sensing and hydrogeophysics in which geophysical methods are used to describe soil patterns and dynamics that shape agronomic management (including precision agriculture). To fully realize its potential for optimizing agricultural production, current barriers and targets for future agrogeophysics research must be identified. In this review, we compare the trajectory of agrogeophysics within peer-reviewed literature, patents, and the US university extension literature and examine the current challenges and opportunities for supporting agricultural production and sustainability with agrogeophysical tools. We conducted a repeatable search of Web of Science and Scopus for seven geophysical methods (electromagnetic …

Attitudes Towards Insects: An Attempt To Change Negative Attitudes To Neutral Or Positive, Christina Chapman

Department of Entomology: Distance Master of Science Projects

Purpose and Summary

The purpose of this project was to examine whether negative attitudes towards insects could be changed in children after learning about them in a safe and enjoyable environment. At the start of this project, I was a science teacher in an urban middle school, where most students were neither fond of nor interested in insects. This experience shaped my project: I wanted to change attitudes from negative to positive, transforming “eww gross, kill it!” into “let it live; it has a job to do.” Through my studies in the entomology program, my belief that insects are highly …

Up In Smoke: How Recent Court Rulings Have Torched Big Tech’S Litigation Strategy And Why It Matters, David Earl Wietlispach

Nebraska Law Bulletin (Selected Issues)

As the title of this paper suggests, there are parallels between what happened to Big Tobacco and what could happen to Big Tech should its litigation strategy fail. Big Tech, like Big Tobacco before it, could stand to lose billions of dollars in judgments and settlements. More importantly, regulations—if allowed to take root—could upend Big Tech’s platform business model. Either outcome, or both, could fundamentally rewrite the relationship between Big Tech and its users. If Big Tech’s litigation strategy truly goes up in smoke, these colossal corporations could find themselves in a magnificent mess.

Adaptation Planning To Mitigate Flood Risk: Bellevue, Nebraska As A Case Study, Michael Nti Ababio

Community and Regional Planning Program: Theses

Flooding remains one of the most pressing natural hazards in the United States, with increasing frequency and intensity driven by climate change. This thesis explores the adaptation planning strategies employed to mitigate flood risks in Bellevue, Nebraska, a city significantly impacted by the 2019 floods in eastern Nebraska. Using a mixed-methods approach, the study combines quantitative analysis of flood vulnerability with a critical review of local planning policies using documents, zoning ordinances and institutional frameworks. Spatial analytical tools such as Global Moran’s I and Hot Spot Analysis (Getis-Ord Gi*) were used to detect clustering of inundated buildings during the 2019 …

Data-Driven Methods For Signal Analysis And Nonlinear System Identification, Cristian Felipe López Ruano

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

In recent years, data-driven modeling has gained considerable attention in nonlinear system identification, offering a powerful alternative to traditional physics-based methods. This has been possible by advances in machine learning, sparse regression, and differential equations in a weak form, which allow the accurate capture of complex nonlinear dynamics, even when the measurements are in strong background noise. Moreover, integrating these models with physical knowledge further enhances their reliability and interpretability, making them suitable for a wide range of science and engineering applications.

In this dissertation, we investigate algorithms for data-driven nonlinear system identification to obtain ordinary differential equations that govern …

Water Current, Volume 57, No. 2, Summer 2025

Water Current Newsletter

No abstract provided.

Soil Health In Nebraska: Exploring Practitioners' Needs And Insights From A Long-Term Organic Farm, Ingrids Isabel Mata Vigil

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

Soil health is foundational to sustainable agriculture, environmental resilience, and long-term food security. Yet, the adoption of soil health assessments remains limited, often perceived as too technical, costly, or difficult to implement in real-world contexts. To better understand these challenges, the first chapter presents findings from a statewide survey of 41 soil health practitioners in Nebraska, including farmers, extension educators, NRCS staff, and conservation professionals. Respondents highlighted the need for simpler, more accessible, and context-specific tools for soil health assessment that help practitioners make informed decisions aligned with their management goals. Complementing these insights, the second chapter includes an independent, …

Evaluating The Effects Of Row Spacing, Legume Intercropping, Fertilizer Source, And Fertilizer Timing On Intermediate Wheatgrass In Eastern Nebraska, Madeline M. Johnston

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

Kernza^® is the trademarked name of the perennial crop intermediate wheatgrass (Thinopyrum intermedium). In addition to its potential for dual-use as a grain and forage crop, Kernza is marketed to provide needed environmental services by increasing crop biodiversity, sequestering soil carbon, and reducing nitrate leaching. However, more work is needed in cultivar selection and crop management to increase total grain yields and prevent long-term grain yield decline. Furthermore, research in quantifying and understanding Kernza’s ability to affect soil properties and water dynamics is limited.

Two field experiments were conducted at the Eastern Nebraska Research Extension and Education …

Evaluating Biodegradable Mulch As A Soil Conservation Tool And The Impact On Soil Properties And Yield In Soybean (Glycine Max) Cropping Systems In Eastern Nebraska, Ana Clara Gomes

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

This study, conducted during the 2024 growing season, evaluated short-term effects of soil management practices on greenhouse gas (GHG) emissions, soil microclimate, nitrogen dynamics, weed suppression, and soybean (Glycine max) yield. In addition to conventional tillage and no-till, this research included cereal rye (Secale cereale) cover cropping and a novel sprayable biodegradable mulch (BioWRAP®) to assess emerging strategies for sustainable soybean systems under contrasting moisture regimes.

Field trials were established at two eastern Nebraska locations: Havelock (dryland, silty clay loam) and ENREEC (irrigated, clay loam). A strip-block randomized design with four replications tested six soil management …

The Lived Experience Of Religious Trauma Among Transgender And Gender Diverse People: An Interpretative Phenomenological Analysis, Patrick T. Meyer

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

Religion has served as a framework to support the psychological well-being of people across cultures throughout human history, yet there is growing scholarly and public interest in how religious institutions and people inflict harm on members through spiritual means. Extant literature demonstrated that transgender and gender diverse (TGD) people experience gendered microaggressions in religious spaces, and their social position within the church likely holds unique insights into the subjective experience of religious trauma. Even though research with people who have had adverse religious experiences has increased over time, little is known about TGD people who experience lasting psychological damage due …

Development And Implementation Of A Vector-Quantized Transformer Autoencoder For Monitoring Bicycle Road Conditions, Kewei Ren

Department of Construction Engineering and Management: Dissertations, Theses, and Student Research

Adviser: Chun-Hsing Ho

The long-term, sustainable assessment of bicycle road conditions is essential for ensuring cyclist safety and promoting equitable infrastructure management. While traditional detection methods based on manual thresholds have demonstrated some effectiveness, they carry limitations due to the diversity of pavement materials, cyclist behaviors, and sensor platforms. Although recent advances in deep learning offer promising alternatives, established techniques are primarily applied to highway anomaly detection and are rarely adapted for bicycle roads. Furthermore, most related studies lack clear definitions for anomalies and transparent annotation procedures, resulting in a shortage of effective datasets and detection methods specifically for bicycle …

Extracting From The Extracurriculum: Using Extracurricular Composition Practices To Bring Purpose, Voice, And Engagement Back To The English Classroom, Grace N. Ellis

Department of English: Dissertations, Theses, and Student Research

This thesis explores how principles and practices from extracurricular literacy spaces and the extracurriculum as a whole can inform and revitalize the secondary English classroom. In response to growing student disengagement, apathy, and disconnection, particularly within highly standardized and product-focused classrooms, this argument investigates how programs such as the Nebraska Writers Collective’s All Writes Reserved program and the University of Nebraska–Lincoln’s Young Writer Camp model authentic engagement, identity exploration and development, and rhetorical agency through creative, student-centered writing practices. Drawing from composition theory, educational research, and experiential data from Nebraska-based writing initiatives, the thesis argues that incorporating choice, safe-risk taking, …

The Effect Of Individual Variation On Epidemiological Dynamics: From Super-Spreaders To Landscapes Of Risk, Alexis Shannon Beagle

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

Individuals that make up a population always display some level of variation between members. At the smallest scale, individuals always maintain genetic variation, but variation continues to arise at other scales of biological organization from physiological or immunological variation within individuals to variation in behavior between individuals that can be both genetically and environmentally mediated. The role of individual variation is particularly important in the context of infectious diseases because there is strong evidence that infections are highly heterogenous, indicating that patterns of individual variation drive a significant portion of the epidemiological patterns we observe. Individual variation leads to heterogeneity …

Use Of High-Throughput Phenomics With And Without Fungicide As A Wheat Breeding Tool, Gerardo Ivan Rivera Collazo

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

Wheat (Triticum aestivum) is an important food staple for many countries around the world and current consumption and production data demonstrate a production deficit. Breeders are challenged to help close this gap in production by selecting better cultivars with improved yields. Several methods aim to accelerate the breeding process to reduce the time required for releasing an elite variety. One of the main breeding bottlenecks is the lack of fast and reliable phenotypic data acquisition that could dissect physiological and morphological plant data. High-throughput remote sensing could have the potential to reduce this bottleneck by streamlining data acquisition, …

A Study Of Ice And Fire: Environmental Change Impacts On Lakes Of The Nebraska Sandhills, Daniel Gschwentner

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

The Nebraska Sandhills contain thousands of shallow, groundwater-fed lakes. These lakes are extremely sensitive to environmental and climatic changes due to their isolated hydrological setting and small volume. Building on previous work on the hydrology, geochemistry and long-term climate response of Sandhill lakes, my research considers how ecosystem processes such as primary production, nutrient limitation and water quality respond to short-term environmental and climatic change. In my first data chapter, I highlight that Sandhill lakes are nitrogen (N) but not phosphorus (P) limited and that N:P ratios are poor predictors of nutrient limitation status in Sandhill lakes. In my second …

Catching A Fever: A Comparison Of Vachellia Xanthophloea Populations In The Limpopo And Luvuvhu River Floodplains Of The Makuleke Contractual Park, Kianie B. David

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

This study investigates patterns of stand structure regeneration, growth characteristics, and coarse woody debris (CWD) patterns in Vachellia xanthophloea (fever tree) stands within the Makuleke Contractual Park (MCP), a semi-arid savanna system in northern Kruger National Park (KNP), South Africa. Fieldwork was conducted across two stand types: a monospecific fever tree stand in Rietbok Vlei and a mixed-species stand in the Western Nhlangaluwe Floodplain where fever tree is established with Faidherbia albida (ana tree). Data were collected from 20 total 1/4-acre (1,011 m²) circular plots between both stands in 2024 and 2025, including seedling root collar diameter (RCD), …

Bioenergy Crop Production: Implications For Grassland Bird Communities In Southwestern Nebraska, Grace E. Schuster

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

Biofuel and bioenergy systems are components of most climate stabilization pathways to reduce greenhouse gas emissions and limit global warming. Currently, corn (Zea mays) is the predominant feedstock used for bioenergy production in the United States. However, widespread production of this monoculture crop has resulted in many negative environmental impacts. The most notorious impact has been the loss of grassland habitat due to agriculture expansion which has had detrimental effects on wildlife that depend on grassland habitat. One such group, grassland birds, has faced steeper, more consistent, and more widespread declines than any other avian guild. Therefore, strategies …

Biocomputing Approach To Modeling And Modulating Calcium Signaling, Sehee Sun

School of Computing: Dissertations, Theses, and Student Research

Biocomputing is an emerging field that seeks to perform computational tasks using biological substrates and processes. Unlike conventional computing systems based on silicon hardware, biocomputing leverages the parallelism, energy efficiency, and complex dynamics of living systems. Among various cellular mechanisms, calcium (Ca2+) signaling stands out as a central regulator of diverse biological functions, offering a promising basis for programmable logic and control in living cells.

This thesis introduces a novel framework for modeling and modulating Ca2+ dynamics using biologically inspired Boolean logic circuits. Specifically, we propose the Ca2+ Boolean Logic (CaBL) model, in which Ca2+ fluxes and interactions are abstracted …

Cazyme Gene Cluster Diversity In Human Gut Microbiome, Yi Xing

Department of Food Science and Technology: Dissertations, Theses, and Student Research

In gut microbiome research, carbohydrate-active enzyme gene clusters (CGCs) have emerged as key functional units for understanding microbial glycan degradation. Unlike taxonomic or broad pathway annotations, CGCs offer gene-cluster-level resolution and capture substrate-specific microbial functions. However, their diversity and distribution in relation to host metabolic phenotypes, such as obesity, remain poorly characterized. This study tests the hypothesis that the composition and abundance of fiber-targeting CGCs vary between obese and healthy human gut microbiomes, reflecting distinct microbial carbohydrate utilization strategies. To examine this, we constructed a high-quality reference CGC dataset comprising 94,019 clusters from the Unified Human Gastrointestinal Genome and profiled …

Overcoming Maternal Antibody Interference In Swine Influenza: Advancing Dna Vaccine Strateies For Enhanced Immune Protection In Piglets, Danh Cong Lai

School of Veterinary and Biomedical Sciences: Dissertations, Theses, and Student Research

Maternally derived antibodies (MDAs) play a vital role in protecting neonates from infectious diseases, but their presence at the time of vaccination can interfere with vaccine-induced immune responses, thereby reducing vaccine effectiveness. MDA interference has been documented in pigs vaccinated with whole inactivated virus (WIV) vaccines against swine influenza A virus (IAV). In this thesis, we evaluated the efficacy of a lipid nanoparticle encapsulated DNA (LNP-DNA) vaccine against swine IAV in the presence and absence of MDAs, comparing it to a WIV vaccine. In MDA-negative piglets, both the LNP-DNA and WIV vaccines induced strong immune responses and effectively prevented the …

Exploring And Characterizing Organic Chemistry Students’ Meaningful Engagement In Science Practices, John Zhou

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

Undergraduate organic chemistry frequently engages students in key science practices such as analyzing and interpreting spectroscopic data and constructing explanations through reaction mechanisms. However, these activities are often framed as procedural tasks rather than as tools for constructing knowledge. As a result, students may develop incomplete understanding of these practices, making it harder for them to see how scientific knowledge is generated and to use them meaningfully as tools for sensemaking. To better understand how students take up these practices as epistemic tools, three qualitative studies were conducted in this dissertation to investigate how undergraduate organic chemistry students reason with …

Primary Investigation Of Rice-Fish Co-Culture: Investigating The Feasibility Of Raising Fish In Flooded Rice Paddies In The Southern Usa, Yulin Jia, Aaron K. Jackson, Bartholomew Green, S. Adam Fuller, Heather Box, Laduska Sells, Candis Ray, Paxton Harper, Brennan Smith

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

With limited land and water resources available it has become critical to maximize output for agricultural products while maintaining sustainable farming practices. Ricefish co-culture can be used to maximize limited land and water resources for production of rice and fish concurrently and reduce the need of chemical inputs. While rice-fish co-culture has been practiced in Asia for centuries, very few studies have examined the feasibility and economic impact of rice fish co-culture in the U.S.A. Two studies were conducted in Stuttgart, Arkansas, U.S.A. from 2023-2024 to investigate the suitability of raising Koi carp in flooded rice paddies with a sushi …

Reaction Control Mechanism In Deoxyuridine 5'-Triphosphate Nucleotidohydrolase, Aaron Delay

School of Biological Sciences: Dissertations, Theses, and Student Research

Deoxyuridine 5'-triphosphate nucleotidohydrolase (dUTPase) is an enzyme involved in the pyrimidine biosynthesis pathway, a key component of cellular DNA metabolism. It regulates intracellular uracil carrying triphosphate levels by hydrolyzing dUTP, thereby providing a substrate for thymidylate synthase (TS). The effective inhibition of dUTPase is expected to enhance TS-targeted chemotherapy by promoting thymine-less apoptosis.

Although the reaction mechanism of dUTPase has been studied, the human nuclear homotrimeric form remains complex, as all three subunits cooperatively form a single active site. As a result, the detailed molecular dynamics of its catalysis are still not fully understood. In this study, I investigated the …

A Discrete-Time Adaptive Sliding Mode Controller For A Multicopter With A Suspended Payload, John Helzer

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

This thesis presents a Discrete-time Adaptive Sliding Mode Controller (DASMC) for control of a multicopter with a suspended payload. DASMC is designed to stabilize the multicopter at a desired position while minimizing the load oscillations induced by a significant hanging payload. The proposed DASMC minimizes the need for system-specific parameters like tunable gains and improves robustness to both external disturbances and model uncertainties compared with existing controllers. The controller is designed for direct digital implementation on a variety of multicopter platforms with considerations like discrete-time design, adaptive gain shrinking, and saturation handling. When deployed on a real multicopter in an …

A Quantitative Examination Of The Sexual Health Of Aging Black Men In Rural South Africa, Esihle Lupindo

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

This dissertation uses survey data primarily from Wave 1 of the Health and Aging in Africa: Longitudinal Study of In-depth Community in South Africa (HAALSI) which was collected in 2015 to study the sexual health of Black men in rural Mpumalanga, South Africa. Broadly speaking, I examine aging men’s sexual health as it related to HIV, well-being, loneliness, social networks and disclosure. The definition that I use for sexual health was coined by MacPhail and Campbell (2001) who define it as “not only sexual practices but also what people know and believe about sex, particularly what they think is natural, …