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Bridging Conservation And Disaster Recovery: A Dual Study On Wetland Program Plans Evaluation And Midwest Post Disaster Recovery Assessment, Rao Nargis Jahan

Community and Regional Planning Program: Theses

Wetlands provide essential ecological, social, and economic benefits for our society. In the United States, states and tribes play crucial roles in wetland protection, restoration, and management. However, no research has systematically measured state-level wetland planning efforts towards national conservation goals. This study is the first to comprehensively evaluate how state-level Wetland Program Plans (WPPs) align with national missions, particularly the "no-net-loss" of wetlands goal. Our research assesses the EPA-approved state-level WPPs from 42 out of 50 states in the United States during the period from 2015 to 2024. Using a protocol of 30 indicators across five categories, this study …

Flood Resilience Through Working-Land Conservation: Assessment Of Wetland Inundation Dynamics Across Wrp, Wma, Wpa, Padus And Crp Lands In Nebraska (2018–2024), Pranjay Joshi

Community and Regional Planning Program: Theses

This study first confirms whether Nebraska’s wetlands are still functioning hydrologically in ways that reduce flood impacts. Wetlands are known to lessen flood damage by storing water, slowing runoff, and moderating peak flows, but these benefits depend on the wetlands’ ability to maintain inundation and saturation through time. Many wetlands across the state have undergone drainage, hydrologic alteration, or isolation from surrounding watersheds, raising uncertainty about their present-day functioning. Using seven years of Sentinel-2 imagery processed in Google Earth Engine, this research establishes a clear, long-term record of inundation patterns across thousands of wetland parcels. This analysis verifies which wetlands …

A Comparative Analysis Of Complete Streets And Multimodal Transport Approaches: Implications For Sustainable Urban Mobility In Lincoln, And Global Contexts, Oliva Richard Kilyenyi

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

Movement of people and goods in urban areas through different modes of transportation including walking, cycling, public transit and by autos is termed as urban mobility. Urban mobility presents significant environmental, social, and economic challenges for cities worldwide as they grapple with the impacts of conventional transportation systems, particularly in North America context where car-centric planning approaches has dominated urban developments since 1950s. Car-centric dominance is 80% in North American Metropolitan areas (Manaugh et al., 2015). The impacts of these conventional systems include greenhouse gas emission emissions contributing approximately 24% of global carbon dioxide (CO₂) emissions, air pollution …

A Temporal Extension Of Tasselnet With Uncertainty Quantification Using Bayesian Latent Autoregressive Model, Gayara Demini Fernando Muthunama Gonnage

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

Manual counting of maize tassels remains a time-consuming and labor-intensive process. Automating tassel counting using maize field images has received significant interest, with researchers exploring methods to streamline this task. Accurate tassel detection can substantially reduce both time and labor costs, offering a practical solution for large-scale agricultural management. Current studies in this area predominantly focus on training object detection algorithms to enhance prediction accuracy and efficiency. Images for this task are often captured in sequences, meaning they capture the exact location of the maize fields over time. However, existing tassel detection and counting methods typically ignore this sequential nature, …

Patch Mow Grazing: Investigating The Effects Of Mowing On Forage Nutritive Value, The Biomass–Nutritive Value Relationship, And Herbivore Selection, Trace R. Stauble

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

Herbivore foraging behavior plays a critical role in shaping grassland structural heterogeneity, with selection often driven by forage biomass and nutritive value. Currently, it is thought that herbivores primarily select areas that are greater in nutritive value, and low in biomass. More specifically, disturbances like fire and grazing have been thoroughly studied showing that recently burned and grazed areas are not only higher in nutritive value but disproportionately selected by herbivores in comparison to undisturbed areas. However, most studies address only narrow ranges of defoliation, comparing intensely defoliated sites (< 10 cm) to those that are either not defoliated or have experienced a much longer time since defoliation, thereby decreasing grazing pressure as biomass increases. However, one of the most widely used methods of defoliation in grasslands, mowing, hasn’t been thoroughly studied for its effects on nutritive value, and how it impacts herbivore selection. Our study aimed to (1) evaluate how mowing treatments—i.e., short (5 cm), medium (18 cm), and tall (>30 cm, unmown)—affect nutritive value and herbivore selection, (2) assess …

Cover Crop Influence On Arthropod Biodiversity And Soil–Water Dynamics In A Semi-Arid Maize–Soybean Sequence Of The Nebraska High Plains, Carlos Eduardo De Oliveira Martins

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

With the expansion of cover crop (CC) use in semi-arid regions, producers in the Nebraska High Plains are increasingly interested in understanding how CCs influence both beneficial arthropods and soil-water within maize-soybean (Zea mays L., Glycine max [L.] Merr.) rotations. Integrating CCs in these systems can enhance soil water availability and beneficial insect activity, but potential trade-offs include higher early-season water use by CCs and the risk of increasing potential pest populations. This thesis addresses these questions through two complementary studies conducted under field conditions near Brule, Nebraska. The first study evaluated the effects of a multi-species CC mixture …

Post-Fire Soil Health Assessment Of The Grasslands And Woodlands In The Semi-Arid Nebraska Sandhills, Stephanie M. Lugo

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

Grasslands in the Nebraska Sandhills are shaped by natural wildfires, which help maintain the structure and function of native grasslands. In recent decades, afforestation with ponderosa pine and eastern redcedar has introduced new woodlands that altered the region’s fire dynamics and raised important questions about the effects of wildfire on different vegetation types. As wildfires become more frequent, understanding their impacts on soil health in grasslands and woodlands becomes increasingly important. This study examines the short-term effects of the 2022 Bovee Fire on physical, chemical, and biological soil properties in native grasslands and ponderosa pine and eastern redcedar afforested woodlands. …

Assessing The Language And Reading Abilities Of Students With Mosaic Down Syndrome, Emma G. Conradi

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

Language and reading are important skills for academic and social success, yet individuals with Down syndrome often face significant challenges developing these skills (Abbeduto et al., 2007; Martin et al., 2009). However, almost all the available research on the language and reading abilities of individuals with Down syndrome comes from research focused on individuals with Full Trisomy 21. To date, there has been virtually no research specifically examining the language and reading skills of individuals with mosaic Down syndrome (Buckley & Bird, 2002), a rare karyotype of Down syndrome. Therefore, the purpose of this study is to describe the language …

Defining The Causal Contribution Of The Gut Microbiota To Cardiomyopathy Pathogenesis As A Basis For Developing Microbiome-Targeted Therapies, Xu Shi

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

Heart failure (HF) is a leading cause of morbidity and mortality worldwide, placing substantial clinical and economic burdens on society. Although advances in therapy have improved patient outcomes, the biological mechanisms that drive HF onset and progression remain incompletely understood. Increasing evidence suggests that the gut microbiota, the trillions of microorganisms residing in the gastrointestinal tract, plays a key role in some forms of heart disease, especially cardiovascular disease. Moreover, gut microbial dysbiosis has been associated with systemic inflammation, metabolic imbalance, and immune dysregulation, all of which contribute to the pathophysiology of HF. Cardiomyopathy, a primary disorder of the heart …

Soil Characterization With Proximal Geophysics, Sophia M. Becker

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

High quality soil data is crucial for addressing numerous threats to human well-being such as water scarcity, food insecurity, and intensified natural disasters. True soil property values are determined by analyzing soil samples in a laboratory, but soil sampling is often expensive and time-consuming. Some in-field point sensors and remote sensing products are available to measure soil properties, but they have inherent limitations in measurement extent and resolution. Geophysical methods can fill the measurement scale gap between point measurements and remote sensing products, but various research questions remain open. This dissertation aims to advance understanding of geophysics-derived soil property measurements …

Ai-Enabled Robotic Nitrogen Management, Ankita Kalra

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

Nitrogen management in corn agriculture faces economic and environmental challenges, motivating development of precision, site-specific solutions. This dissertation presents AIR-N (AI-Enabled Robotic Nitrogen Management), a novel system that integrates cloud-based artificial intelligence with an autonomous field robot (Flex-Ro) to optimize nitrogen fertilizer application in real time. The research is driven by the need to improve nitrogen use efficiency while reducing leaching and emissions.

Comprehensive architecture (Cloud-E) was designed using Amazon Web Services to ingest multi-modal agronomic data (soil sensors, crop reflectance, weather) and host machine learning models. A Random Forest-based model was trained on historical field data to predict spatially …

From Vision To Practice: Implementing An Instructional Model Through Teacher Experience And Leadership Support, Stefanie Novotny

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

Implementing change in any organization is challenging. It requires careful planning, effective communication, and strong leadership. Principals provide support and empower stakeholders to take ownership of the change process. They create opportunities for others to contribute ideas, take on leadership roles, and drive innovation, fostering a culture of shared responsibility and collective action. Change leaders inspire creativity and encourage teachers to think outside the box, leading to the development of new ideas and processes that drive growth and success. This mixed-methods action research study investigated how teachers can enhance educational practices by implementing an instructional model to improve teaching strategies …

Evaluating Fall And Spring Planted Cover Crops For Integrated Management Of Herbicide Resistant Palmer Amaranth And Effect On Soil Health, Vipin Kumar

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

Herbicide-resistant Palmer amaranth (Amaranthus palmeri S. Watson) pose a severe threat to agronomic crop productivity in the United States, including corn and soybean production in Nebraska. Therefore, there is an urgent need for diversified and sustainable management approaches. Integrating cover crops (CCs) with herbicide programs represents a promising strategy to achieve Palmer amaranth suppression, sustain crop yields, and contribute to long-term soil health in irrigated corn–soybean production systems in Nebraska.

A meta-analysis of 41 studies and 595 paired observations demonstrated that CCs reduced Amaranthus spp. density and biomass by 37–59% depending on the growing season, with grasses and mixtures …

Synthesis And Study Of Stable Organic Radicals For Mri Contrast Agents And New Materials, Sabina Dhakal

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

The first part of this dissertation focuses on the design, synthesis, and characterization of a thermally robust S =1/2 phototetrazolinyl monoradical and the development of synthetic methodologies for a high-spin (S = 1) phototetrazolinyl diradical. Electrochemical studies of the phototetrazolium cation (precursor to the monoradical) revealed a remarkably narrow electrochemical band gap (Ecell ≈ 0.82 V), suggesting promising electrical conductivity. Thermal analysis of the monoradical demonstrated excellent stability, with the onset of decomposition at 232 °C. Building on the excellent thermal stability and promising properties for electrical conductivity of the monoradical, we developed two condensation-based synthetic routes that provide viable …

Rainfall-Runoff Modelling In An Indonesian Humid Tropical Area Using Satellite-Based Precipitation Products, Noordiah Helda

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

This dissertation explores three rainfall-runoff models in the humid tropical regions of Indonesia using satellite-based precipitation products (SBPPs) and develops integrated machine-learning modeling frameworks. Several ground-based observations from BMKG (Badan Meteorologi, Klimatologi, dan Geofisika (also known as the Indonesian Agency for Meteorology, Climatology, and Geophysics)) stations across Indonesia (133−165 stations) are compared and evaluated against satellite products, indicating that GPM performs well, with R-squared values ranging from 0.54 to 0.76 and correlation coefficients ranging from 0.45 to 0.69, respectively.

In the Martapura Watershed, South Kalimantan, due to a lack of observational discharge data, streamflow was generated using the FJ Mock …

Public Perceptions Of Leadership Effectiveness In Ethiopia Over The Last Decade, Fikadu Reta Alemayehu

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

Ethiopia is one of the largest countries in Africa, with a fast-growing economy, rich history, diverse agroecology, more than 70 languages, and a population exceeding 130 million. However, the country continues to face serious internal conflict, high malnutrition, and economic hardship, while the study of leadership effectiveness remains limited and lacks consistent longitudinal research. To help fill this gap, this study examined how public perceptions of leadership effectiveness and development outcomes changed in Ethiopia between 2013 and 2023, using Afrobarometer survey data. The analysis explored how citizens’ views about governance, wellbeing, and access to services evolved during a decade of …

Large-Scale Experimental Study On The Impact Of Air Cleaning & Ventilation On Indoor Air Quality And Student Illness-Related Absenteeism, Daud Nosham

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

This large-scale randomized experimental field study investigated the effect of portable air purifiers (PAPs) on classroom’s air quality and student’s illness related absenteeism. PAPs were installed in 317 classrooms from various school districts located in Eastern Nebraska. The classrooms were randomly assigned into four conditions: three treatment conditions (T1, T2 & T3) and one control condition (device without any filter). T1 was equipped with HEPA filters, T2 added Activated Carbon (AC) layer to HEPA, and T3 further integrated Germicidal Ultraviolet (GUV) alongside HEPA and AC filters. The measured variables were carbon dioxide (CO2), fine particles (PN2.5) and coarse particles (PNcoarse), …

Assessing Crop Rotation Productivity, Soil Health, And Fertility, And Economic Performance, To Enhance Semi-Arid High Plains Cropping Systems Sustainability, Ezequiel Maria Villamil

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

Sustainable crop production in the semi-arid High Plains of Nebraska faces challenges from limited precipitation, high interannual variability, and economic risk. This dissertation investigates the long-term productivity, water use, soil health, and economic sustainability of dryland crop rotations, with emphasis on the role of pulses as alternatives to fallow.

Chapter 1 analyzes nearly three decades (1995–2023) of on-farm data from the High Plains Agricultural Laboratory (Sidney, Nebraska) to compare seven crop rotations, including wheat, corn, millet, sunflower, and field peas. Results showed that wheat–corn–fallow (W–C–F) consistently outperformed traditional wheat–fallow (W–F) and more intensified four-year rotations, providing the highest grain yields, …

Resources For The Beginning And Intermediate Jazz Educator: Reviews Of Modern Resources And Implementation In The Classroom, Bryan Canonigo

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

This document is a compilation and discussion of different modern jazz education resources geared towards beginning and intermediate students. It is intended for the younger high school jazz educator who may have just started their careers and are searching for new(er) resources to aid their teaching and rehearsal techniques. For the seasoned high school jazz educator, this document may suggest additions to their current lesson plans and/or updates to their current resource compilations and rehearsal practices. A primary goal of this document is to suggest ideas to aid these educators in teaching jazz music more wholistically, in small or large …

Development Of Databases For Glycan Utilization And Anti-Prokaryotic Defense In Microbiomes, Yuchen Yan

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

Microbiomes in humans, animals, plants, and other environments are necessary components of the biosphere for global nutrient cycling and maintaining ecosystem balance. In particular, the gut microbiome plays an essential role in modulating human health through glycan utilization. Carbohydrate-active enzymes (CAZymes), CAZyme gene clusters (CGCs), and polysaccharide utilization loci (PULs) are key genomic features that determine microbial capacities for carbohydrate metabolism. Meanwhile, the arms race between phages and prokaryotes has led to the evolution of various anti-prokaryotic immune systems (APIS) in phages to counteract prokaryotic immune systems (PIS).

As bioinformatics methods used to analyze microbiome information advance rapidly, there is …

Advancing Precision Agriculture Through The Application Of Remote Sensing Technologies In Plant Health Assessment, Thomas Wilbur Davis

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

Monitoring plant health, including nutritional status assessment, is an important component of crop management decisions. This doctoral document addresses the use of agricultural remote sensing through focused investigations of plant disease detection and nutrient status assessment technologies that advance precision agriculture. The first chapter provides a comprehensive overview of remote sensing technologies in agriculture and examines current capabilities, limitations, and future directions. The final two chapters address studies that evaluated the virus-nitrogen interaction in wheat and compared methods to determine the nitrogen status of midseason field corn.

The first study evaluated the wheat streak mosaic virus (WSMV) × nitrogen interaction …

Detecting Prescribed Fire, Haying And Grazing Events Via Remote Sensing To Create Grassland Disturbance Landcovers For The Ring-Necked Pheasant (Phasianus Colchicus), Megan A. Baldissara

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

This dissertation developed disturbance detection models to fulfill the need for remote sensing landcover products describing grassland structure. The use of landcover products derived from remote sensing is increasing over time in pheasant (Phasianus colchicus) research. Such landcover, however, does not provide relevant pheasant structural habitat information (Chapter 1). Pheasants require tall, high-density grassland for nesting, tall grassland with medium density for brood rearing, and tall grassland for wintering. Time since disturbance can serve as a proxy for structure, as it shapes vegetation by removing biomass and resetting succession. Disturbance is easier to detect than structure with current …

On Bayesian Empirical Likelihood-Based Method For Complex Survey Data With Application To Non-Probability Sampling, Md Hasibur Rahman

Department of Statistics: Dissertations, Theses, and Student Research

This thesis develops a Bayesian empirical likelihood (BEL) framework for inference under complex survey designs and extends it to non-probability sampling. Parametric likelihood based methods are difficult to apply to complex survey data because the likelihood is rarely available in closed form. EL provides a flexible alternative by replacing the parametric likelihood with an empirical likelihood constructed from moment conditions. The proposed method first integrates empirical likelihood constraints with survey design features then extends BEL to non-probability sampling through selection models and design consistent restrictions. Posterior inference is carried out using a Metropolis–Hastings MCMC algorithm. A real-data analysis further illustrates …

Brands & Virtual Personas: How Virtual Influencer Types Impact Brand Awareness, Carol Calderon Ambelis

Department of Textiles, Merchandising and Fashion Design: Dissertations, Theses, and Student Research

As social media continues to shape how consumers interact with brands, virtual influencers (VIs) have emerged as a new type of digital celebrity. While previous research has explored how VIs contribute to brand image and awareness, there has been limited attention on how different types of VIs, both anime-like and human-like, affect consumer perceptions across different markets. This study examines how these two types of VIs impact relatability, aspiration, and brand awareness, with a focus on the differences between luxury and mass market. Using a within-subjects experimental design, this study recruited 574 participants with social media experience using MTurk. The …

The Role Of Peroxisomal Acot4 And Acot8 In Modulating Lipid Metabolism And Stress Pathways In Steatotic Hepatocytes, Sylwia Miekus

Department of Nutrition and Health Sciences: Dissertations, Theses, and Student Research

Metabolic dysfunction-associated steatotic liver disease (MASLD) is characterized by excessive lipid accumulation in hepatocytes and the development of lipotoxic stress that disrupts cellular homeostasis. Peroxisomal lipid metabolism plays an important role in maintaining acyl-CoA balance during fatty acid overload, yet the contribution of peroxisomal acyl-CoA thioesterases to early lipotoxic responses remains insufficiently understood. The aim of this study was to investigate the functional involvement of the peroxisomal enzymes acyl-CoA thioesterase 4 (ACOT4) and acyl-CoA thioesterase 8 (ACOT8) in hepatocyte lipid handling under acute lipotoxic conditions. An in vitro model of steatosis was established in AML12 cells through exposure to a …

A Low-Power Mixed-Signal Potentiostat System-On-Chip With Integrated Dual-Slope Adc, Seth Mcrobert

Department of Electrical and Computer Engineering: Dissertations, Theses, and Student Research

This thesis presents the design and characterization of a low-power mixed-signal potentiostat that was integrated with a 65 nm core in a SoC for low-power electrochemical sensing applications. The system integrates a low-noise transimpedance-based potentiostat front end with a 12-bit dual-slope analog-to-digital converter (ADC) for accurate current-to-digital conversion. The potentiostat core—comprising the control amplifier, current-mirror network, and transimpedance amplifier—consumes 38.2 µA from a 2.5 V supply (95.5 µW) and achieves an input-referred noise floor of 113 µVRMS over a 330 Hz bandwidth, while having an input current range from 1 nA to 20 µA and a noise-limited sensitivity of 56.4 …

Characterization Of Mitochondrial Dna Repair Components And Repair Choices At Targeted Double-Strand Breaks In Arabidopsis Thaliana, Moira Rodriguez

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

Plant mitochondrial genomes are complex when compared to most other eukaryotic mitochondrial genomes. They are large and variable in size, expand and rearrange frequently, abundant in non-tandem repeats, but maintain a very low synonymous substitution rate in the remaining coding regions. Many of these complexities can be explained by the increased use of double-strand break repair for DNA damage. To advance the understanding of mitochondrial genome dynamics as it relates to double-strand break repair, we performed a forward genetics screen to identify proteins involved in DNA repair in plant mitochondrial genomes. Through this screen, we identified an RNA/DNA helicase, Suv3, …

Investigating Programming Behaviors To Understand Student Engagement And Experience In Introductory Programming Courses, Marcus Eugene Gubanyi

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

Introductory programming courses are foundational to developing students’ problem-solving abilities and shaping their persistence in computing pathways. Engagement with programming tasks plays a central role in student learning and experience. Many research measures, including self-reports and code submissions, offer only a limited view of student engagement with programming tasks. This dissertation leverages programming process data, consisting of keystrokes and compilation events, to capture the programming process as it unfolds and to investigate observable programming behaviors. Guided by educational theories, three studies examine how students’ programming behaviors vary across instructional and assessment contexts, how they relate to motivational profiles, and how …

Proso Millet In Us High Plains Dryland Agriculture: Systems Resilience, Phenology, And Consumer Preferences For Alternative Grains, Pratiksha Baishya

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

Dryland crop production in Nebraska's semi-arid High Plains faces challenges from fluctuating weather impacts of climate change, including extreme temperatures, short growing seasons, and recurring droughts. Proso millet is an alternative crop used to build a more robust three-year rotation in the region, rather than the traditional two-year wheat-fallow cycle. This dissertation provides a systems-level assessment of proso millet, a climate-resilient crop with great potential to support sustainable cropping systems in the US High Plains. Using a field-to-consumer approach, it highlights its agronomic and environmental advantages in dryland rotations, develops a phenological framework to aid future research on production, crop …

Modelling Groundwater Nitrate Transport In Bazile Creek Watershed Using Modflow, Prajwol Thapa

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

Excessive application of inorganic nitrogen fertilizers has led to pervasive nitrate contamination of groundwater in agricultural regions worldwide. This study evaluates the fate and transport of nitrate beneath the Bazile Creek watershed in northeastern Nebraska by coupling groundwater‐flow (GWF) and solute‐transport (GWT) simulations within MODFLOW 6. A conceptual model was developed using hydrogeologic, topographic, recharge, and boundary‐condition data, and the domain was discretized with a quadtree-refined grid to capture surface-subsurface interactions. The steady-state flow model was calibrated against observed hydraulic heads and baseflow measurements using NSE, RMSE, and PBIAS metrics, and subsequently extended to a transient flow simulation spanning 2002-2023. …