Digital Commons Network^™

Two-Photon Imaging For Characterizing Tumor Microenvironmental Changes In Non-Small Cell Lung Cancer Associated With Metastatic Recurrence, Paola Monterroso Diaz

Graduate Theses and Dissertations

Lung cancer remains the leading cause of cancer deaths, comprising nearly 25% of all cancer deaths (Sung et al., 2021a). The five-year survival rate of patients with non-small cell lung carcinoma (NSCLC) remains significantly low given that over half present with locally advanced or metastatic disease at time of diagnosis, and experience tumor recurrence following therapeutic intervention (Tamura et al., 2015; Uramoto & Tanaka, 2014). Current evaluation techniques to assess treatment response are lacking, given they are implemented several weeks after treatment completion and are solely based on anatomical changes in tumor size, forgoing other criteria such as functional or …

An Exploration Of Adverse Childhood Experiences In K-12 Teachers, Michelle E. Marciniak

Doctorate in Education

“Trauma during childhood has the potential to adversely affect one’s physical, cognitive, emotional, and social development across the lifespan” (Champine et al., 2021). Given the epidemic of trauma across the United States, it is statistically probable that teachers who serve in the trenches to provide safe, engaging, and nurturing environments for students are still suffering from the impacts of Adverse Childhood Experiences (Dunn, 2022). This qualitative grounded theory study sought to capture and highlight the experiences of 12 K-12 teachers who have experienced past childhood trauma and shed light on their experiences in the classroom day to day. Participants were …

Exploring Green Photochemical Reactions Of Bio-Based Heterocyclic Compounds: 4-Hydroxy-2(5h) Furanone And 2-Pyridone, Solmaz Asadi

Theses and Dissertations

The present work examines the photoreactivity of 4-hydroxy-2(5H)-furanone and 2-pyridone un-der varying conditions, with the aim of investigating how solvent and wavelength can influence their photochemical reactivity. In the first chapter, the photoreactivity of 4-hydroxy-2(5H)-furanone in its crystalline state was observed to undergo a [2+2] photocycloaddition reaction when exposed to UV-C light and led to a new cyclobutane containing dimer (CB-SA-1). More impressively, CB-SA-1 was determined to be stable at room temperature for two years. This method was solvent-free and catalyst-free offering an environmentally friendly method for synthesizing furanone deriva-tives. Further, in order to study the photoreactivity of 4-hydroxy-2(5H)-furanone in …

The Impact Of Land Use And Land Cover Change On Vegetation, Ecosystem Dynamics, And Conservation In The Northern Great Plains, Seth R. Fore

Theses and Dissertations

Land use and land cover change (LULCC) is one of the primary contributors to global biodiversity and habitat loss. Identifying sustainable development strategies requires understanding the social drivers of land use and conservation decisions as well as their impacts on ecological processes. These socio-ecological interconnections were explored in Northern Great Plains region. Results showed that common responses to socio-economic drivers have resulted in widespread loss of grassland areas throughout the region and that shifts in the functional characteristics of plant communities caused by LULCC have significantly altered key ecosystem functions linked to primary production, carbon/nutrient turnover, and water cycling. Expanding …

Developing Inclusive Practices Through Peer Coaching In College Science Teaching, Briana Miller

Theses and Dissertations

Historically underrepresented students pursuing STEM majors encounter systemic barriers. Students are more likely to experience success when faculty implement inclusive practices. Faculty often lack the pedagogical training necessary to adopt inclusive practices, further perpetuating inequities. To eliminate barriers and offer equitable opportunities for success in STEM majors, this case study explores the implementation of peer coaching and Culturally Relevant Science Teaching (CRST) in college level science teaching, focusing on the experiences of three participating faculty. Through a year-long professional development (PD) cycle, three science faculty members from a small liberal arts college engaged in reflective practices aimed at improving their …

Assessing Reproducibility Challenges In Clinical Metabolics, Darcy Lin Cochran

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

Current metabolomics research is expanding to be multiplatform and interdisciplinary. Metabolomic analysis has the potential to provide detailed insight into any biological system of interest to analyze the underlying molecular mechanisms of variables like environment, disease, and genetics. Human clinical metabolomics is a major research area that is often focused on finding biomarkers or panels of biomarkers for different diseases. However, results are difficult to compare across different laboratories since the field of metabolomics has yet to widely adopt best practices for sample preparation, data acquisition and data processing, results are difficult to compare across different laboratories.

This thesis focuses …

Microbiome Variation In Production Phenotypes And The Role Of Colonization History In Microbiome Establishment, Seidu Adams

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

Ruminant-based agriculture is expected to continue to be a major contributor to food security to feed the growing population. At the heart of nutrient degradation of complex organic matter within the rumen are its microbes. These microbes can convert otherwise unusable organic matter into usable protein and energy and can provide up to 50% of the animal’s protein needs and up to 70% of the energy needs. The microbial functional capacity within the rumen determines the nutrients utilized and the end products of fermentation. However, our understanding of microbial functional capacity within the rumen and factors that influence the rumen …

Domain-Specific Machine Learning Approaches For Geospatial Problems, Shine Bedi

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

This dissertation explores novel algorithms for complex geospatial problems at the intersection of environmental, social, and computational sciences. Emphasizing the unique challenges of the geospatial domain, particularly the deviation from the independent and identical distribution (IID) assumption, the research spans various methodologies across different domains, demonstrating the benefits of specialized approaches in spatial analysis.

First, we show that machine learning techniques can be effectively used in environmental modeling, which often has severe class imbalance challenges. Using artificial neural networks (ANN), support vector machines (SVM), and extreme gradient boosting (XGB) and techniques to address class imbalance provides insights into groundwater quality …

Nitrogen Limitation In Soybean: Physiology And Diagnosis, Luzviminda Ann Ramos Sazon

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

In high-yield soybean environments, the seed yield is limited by nitrogen (N) supply. However, the response of soybean to N fertilizer application is inconsistent. Understanding the seasonal N uptake dynamics in soybean can provide insights on diagnosing N limitation if soybean. To understand soybean N dynamics, we assessed seasonal trends on dry matter and N accumulation in vegetative organs (leaves, stems, and petioles) from 42 field experiments. Each experiment included a ‘zero-N’ treatment, where crops relied on N supply from soil and biological N fixation (BNF), and a ‘full-N’ that received ample N via N fertilizer addition. Vegetative storage proteins …

Draft Assembly And Annotation Of The Cuban Crocodile (Crocodylus Rhombifer) Genome, Robert W. Meredith, Yoamel Milián-García, John Gatesy, Michael A. Russello, George Amato

Department of Biology Faculty Scholarship and Creative Works

Objectives: The new data provide an important genomic resource for the Critically Endangered Cuban crocodile (Crocodylus rhombifer). Cuban crocodiles are restricted to the Zapata Swamp in southern Matanzas Province, Cuba, and readily hybridize with the widespread American crocodile (Crocodylus acutus) in areas of sympatry. The reported de novo assembly will contribute to studies of crocodylian evolutionary history and provide a resource for informing Cuban crocodile conservation. Data description: The final 2.2 Gb draft genome for C. rhombifer consists of 41,387 scaffolds (contigs: N50 = 104.67 Kb; scaffold: N50-518.55 Kb). Benchmarking Universal Single-Copy Orthologs (BUSCO) identified 92.3% of the 3,354 genes …

The Effects Of Mosaicism On Biological And Clinical Markers Of Alzheimer's Disease In Adults With Down Syndrome, Laura Xicota, Lam-Ha T. Dang, Alice Lee, Sharon Krinsky-Mchale, Deborah Pang, Lisa Melilli, Sid E. O’Bryant, Rachel L. Henson, Charles Laymon, Florence Lai, H. Diana Rosas, Beau Ances, Ira Lott, Christy Hom, Bradley Christian, Sigan Hartley, Shahid Zaman, Elizabeth Head, Mark Mapstone, Zhezhen Jin, Wayne Silverman, Nicole Schupf, Benjamin Handen, Joseph H. Lee, Alzheimer’S Biomarker Consortium – Down Syndrome (Abc-Ds)

Neurology Faculty Publications

Background Individuals with Down syndrome (DS) are at high risk of early-onset Alzheimer’s disease (AD); yet, some 20 percent do not develop any signs of dementia until after 65 years or in their lifetime. Mosaicism could contribute to this phenotypic variation, where some disomic cells could lead to lower levels of gene products from chromosome 21.

Methods We examined longitudinal neuropsychological and biomarker data from two large studies of DS: the Alzheimer Biomarker Consortium–Down syndrome study (ABC-DS) (n = 357); and a legacy study (n = 468). We assessed mosaicism using karyotyping or GWAS data. Participants had data on plasma …

Training In Ecological Thinking: Narrative Practices For Educational Professional, Cristina Trovato

University of South Florida (USF) M3 Publishing

Since the 1970s, the issue of environmental education has assumed relevance in the context of a theory of training towards new forms of sustainability education. Literary ecology, a discipline born from the contamination of ecology and literature, proposes itself as a critical response to environmental distress, enhancing the implicit dialogue and interconnections between the text and the circumstances of the environment. The literary heritage constitutes a precious resource for promoting, in educational contexts from early childhood, dimensions that range from the cognitive to the emotional and for activating sustainable processes, through ecological paths that develop a civic conscience, capable of …

Targeted Long-Read Sequencing To Quantify Methylation Of The C9orf72 Repeat Expansion, Evan Udine, Nicole Finch, Mariely Dejesus-Hernandez, Jazmyne L. Jackson, Matthew C. Baker, Siva Arumugam Saravanaperumal, Eric Wieben, Mark T. W. Ebbert, Jaimin Shah, Leonard Petrucelli, Rosa Rademakers, Björn Oskarsson, Marka Van Blitterswijk

Neurology Faculty Publications

Background The gene C9orf72 harbors a non-coding hexanucleotide repeat expansion known to cause amyotrophic lateral sclerosis and frontotemporal dementia. While previous studies have estimated the length of this repeat expansion in multiple tissues, technological limitations have impeded researchers from exploring additional features, such as methylation levels.

Methods We aimed to characterize C9orf72 repeat expansions using a targeted, amplification-free long-read sequencing method. Our primary goal was to determine the presence and subsequent quantification of observed methylation in the C9orf72 repeat expansion. In addition, we measured the repeat length and purity of the expansion. To do this, we sequenced DNA extracted from …

Conceptualizing Centrality In Micro-Level Internationalization Through A Decolonial Approach, Omolabake Fakunle

Journal of Comparative & International Higher Education

Micro-level internationalization offers possibilities to explore different human experiences in international higher education. This is especially crucial given well-reported issues of racism, micro-aggression, and underrepresentation of racially minoritized international academic staff, whose voices remain mostly invisible in internationalization discourses. Previous research connects these issues to the continuing legacy of colonial logic, that privileges hegemonic Westerncentric knowledge systems. In this paper, centrality is proposed as a conceptual framework that offers a direct response to the question of epistemicide which Santos (2014) explains as the exclusion of the knowledges of racially marginalized persons [in or with origins] from the Global South. It …

Design And Synthesis Of Therapeutic Molecules Targeted At Metabolic Pathways Of Cancer And Lipid Signaling In Fungal Diseases, Jennifer Uzoamaka Nnaemeka

All Theses

Cancer remains a leading cause of global mortality, with 20 million new cases and 9.7 million deaths recorded in 2022 (WHO, 2024). While advancements like nanoparticles and monoclonal antibodies offer new treatments, they often cause severe toxicity to normal cells. This study introduced novel thiamin-based compounds targeting enzymes critical for cancer cell proliferation. These compounds were synthesized via a three-step process involving tosylation, SN2 coupling with phenolic compounds, and subsequent reactions to form thiamin-like-phenol derivatives. Yields ranged from 50-70%, and Nuclear Magnetic Resonance (NMR) confirmed their structures. Anticancer activity was assessed by the National Cancer Institute. Separately, drug-resistant fungal infections, …

Sorgoleone (Lipophilic Benzoquinones) Levels In The Root Exudates Of Elite Sorghum [Sorghum Bicolor (L.) Moench] Cultivars, Suleica J. Lee

All Theses

Nitrogen loss from cropping systems is significant and is estimated at more than 50% of the amounts applied. Root exudates of certain plant species including sorghum [Sorghum bicolor (L.) Moench] contain sorgoleone which can reduce nitrification and nitrogen loss through biological nitrification inhibition (BNI). Therefore, the goal of this study was to screen selected elite sorghum germplasm comprising hybrids and parents to determine the best sorgoleone secreting cultivars. The hypothesis was that nitrogen loss from croplands could be curbed through exploring sorghum BNI traits. Screening of the cultivars selected was done using an established sorghum culture and extraction pipeline that …

A Report Summarizing Hsc Faculty Participants: Ithaka S+R Coordinated Study Making Ai Generative For Higher Education, Laura J. Hall, Robyn Gleasner

Publications

This report presents findings from the University of New Mexico Health Sciences Center’s (HSC) participation in the ITHAKA S+R study Making AI Generative for Higher Education. Seven faculty members from HSC disciplines including internal medicine, pathology, psychiatry, nursing, radiology, and population health were interviewed to explore their perspectives on generative AI (GenAI) in teaching and learning, research and scholarship, and institutional support. A unique theme of “practice” emerged, reflecting how GenAI is influencing clinical care, bench-to-bedside translation, and the preparation of students for future professional practice. The report highlights faculty experiences, ethical concerns, and support needs, offering insight into how …

Understanding And Intervening In Children's Tick Risk Perceptions And Protective Behaviors: A Grounded Theory, Ariel Dawdy

Department of Entomology: Dissertations, Theses, and Student Research

Children, ages 8 years and younger, are at a particularly high risk of contracting a tick-borne disease. This is partially due to the misconceptions spread about tick protective behavior and a poor understanding of how antibiotic treatment can help. Because most communities and families believe that tick control is the individual’s responsibility, looking at the interaction between ticks and human children is essential to understanding the individual’s motivations to protect themselves. To help alleviate the number of individuals contracting tick-borne diseases, misconceptions must be addressed, intervention programs implemented, and a behavioral change must occur. This study used a qualitative research …

Soybean Cyst Nematode (Heterodera Glycines Ichinohe) Virulence Assay Against Resistance Sources In Nebraska, Pratibha Karki

Department of Plant Pathology: Dissertations, Theses, and Student Research

Soybean cyst nematode (SCN, Heterodera glycines Ichinohe), one of the major yield-limiting pathogens of soybean, is currently found in 60 counties of Nebraska that produce more than 90% of the state’s soybean. Often, yield loss occurs without any above-ground symptoms, which makes it difficult to manage. The primary management option is the use of SCN-resistant varieties. Several soybean plant introductions serve as resistance sources against SCN. Unfortunately, the single source, PI 88788, is used in approximately 90% of resistant varieties and its prolonged use has increased the virulence status of SCN in the U.S. A study was conducted to assess …

Analysis Of Impulsive Differential Equation Models Of Cell Populations Undergoing Radiation Therapy, Abigail D'Ovidio Long

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

Radiation therapy is a mode of treatment which is implemented for approximately 50% of cancer patients. Treatment needs to be able to kill cancer cells, but also do minimal damage to surrounding healthy tissue. We propose two main impulsive differential equation models of radiation therapy to capture the periodic nature of the treatment. These models build off of previous studies using clinical data to ensure biological relevance. The first model incorporates only cancer cell populations, and we provide parameter relationships which theoretically ensure treatment outcomes of cancer eradication, cancer approaching a carrying capacity, and cancer approaching a periodic solution. We …

Local Rural Knowledge And Early Childhood Informal Science Education In Rural Nebraska, Sarah Michelle Paulos

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

This study aims to discover the existing experiences that lead to local rural knowledge (LRK) of specific rural Northeast Nebraska communities. This information will assist in understanding the impact that LRK has on young children’s science knowledge in rural communities. By engaging in hands-on experiences and interactions, science learning goals for children may be achieved and developed through science outreach programs. During Phase 1 of this study, adults in the selected rural communities participated in an online survey indicating their knowledge of various common rural phrases with the option to share personal stories of experiences and family history. This information …

Characterization Of The Final Enzyme In The Coenzyme M Biosynthesis Pathway In Methanosarcina, Connor John Hines

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

Methanogenesis is known to be one of the oldest forms of energy generation on our planet. Methanogens rely on this method of energy conservation and have evolved to metabolize a variety of substrates, including the waste products of other organisms. This feature has made methanogens beneficial to both wastewater treatment and landfill-to-energy projects. Methane itself is a greenhouse gas twenty times more potent than carbon dioxide, viewed as a particularly influential contributor to global greenhouse emissions. Climate change was known to be on the horizon throughout the 20^th century but has made itself known vocally during this 21^{st …}

Variable Selection In Distance Metric Learning And Triplet Constraints For Deep Learning Based Ordinal Classification, James D. Clothier

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

The purpose of this research is to augment linear and kernelized ordinal distance metric learning (L/KODML) techniques with a proposed variable selection methodology that integrates the Sequential Multi-Response Feature Selection (SMuRFS) algorithm. Additionally, we aim to embed ordinal triplet constraints into a deep learning architecture, and to propose a general framework for deep learning-based ordinal classification. A variety of simulation studies and real data experiments were conducted to evaluate the various methodologies. For the distance metric learning and variable selection, results showed that the integration of SMuRFS performed effective variable selection and improved prediction accuracy. For the triplet constraints, incorporating …

Novel Mouse Models To Study The Role Of T Cells In Cardiac Autoimmunity, Meghna Sur

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

Myocarditis patients can chronically develop dilated cardiomyopathy and autoreactive T cells could contribute to the disease pathogenesis, but defining their antigen specificity remains a major challenge. To fill this gap, we generated T cell receptor (TCR) transgenic (Tg) mice specific to cardiac myosin heavy chain (Myhc)-α 334–352 and made a few observations. First, we unexpectedly noted both CD4 and CD8 T cells expressing TCRs specific to Myhc-α 334–352. Second, while Tg T cells from myocarditis-resistant C57BL/6J mice did not respond to Myhc-α 334–352, those from immunized mice responded, indicating that in vivo priming is necessary to break tolerance. Third, upon …

Performance Of Acoustic Telemetry And Space Use Of Pallid Sturgeon In The Lower Platte River, Nebraska, Christopher F. Pullano

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

Pallid Sturgeon (Scaphirhynchus albus) are centenarian, potamodromous, rheophiles that historically occupied the Missouri River and Mississippi River basins. Listed on the U.S. Endangered Species Act in 1990, population declines are attributed to habitat fragmentation and degradation, as well as overharvest, and hybridization. A knowledge gap exists regarding the extent to which tributaries facilitate key life stages for Pallid Sturgeon. This study evaluated the capacity of acoustic telemetry to monitor the movements of Pallid Sturgeon in a shallow, braided tributary to the Missouri River. The specific objectives were to (1) evaluate the environmental variables influencing the performance of acoustic …

Occupancy Of Fish Species Of Greatest Conservation Need And Temporal Patterns Of Assemblage Occurrence In Sandhills Ecoregion, Nebraska Streams, Braxton M. Newkirk

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

Fish species’ occurrence is influenced by environmental conditions across multiple spatial and temporal scales. Alteration to stream systems has the potential to affect occurrence patterns of fish species. Stream systems of the North American Great Plains face threats originating from climate change and anthropogenic activities resulting in negative implications for many fish species. The Sandhills Ecoregion, Nebraska is considered one of the largest intact grasslands in North America, and thus may experience fewer threats than surrounding areas. Stream systems of the Sandhills Ecoregion are home to 12 fish species of greatest conservation need (SGCN). Little context exists regarding the environmental …

Spatial Ecology Of American Bison On Vermejo Park Ranch, New Mexico, Kate Ann Asmus

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

American bison (Bison bison) are a keystone species that impact grassland productivity, plant diversity, and landscape heterogeneity. We used GPS telemetry and a replicate herbivore grazing experiment on Vermejo Park Ranch in northeastern New Mexico to advance understanding of bison spatial ecology and grazing dynamics. First, we evaluated the potentially disparate influences of forage productivity and site fidelity on the size and selection of home ranges of bison. Home range size was strongly negatively influenced by forage productivity. However, home range selection was influenced more strongly by site fidelity than spatial variation in forage, as bison selected home …

(R2104) On The Qualitative Results Of Riemann-Liouville Fractional Order Nonlinear Neutral Singular Systems With Mixed Delays, Abdullah Yiğit, Cemil Tunç

Applications and Applied Mathematics: An International Journal (AAM)

In this manuscript, we discuss new conditions for asymptotic stability of nonlinear Riemann- Liouville fractional mixed-delay neutral singular systems. By constructing a set of improved Lyapunov-Krasovski˘ı functionals (LKFs), we establish some new delay-dependent conditions in terms of matrix inequality, which guarantees that the systems are asymptotically stable. In the particular case, we give four numerical examples with their solutions and graphs via MATLAB software demonstrating the practical applicability of these proven conditions. With this study, some conditions existing in the literature are developed and generalized.

(R2113) A Numerical Method For Solving Linear First-Order Volterra Integro-Differential Equations With Integral Boundary Condition, Zelal Temel, Musa Cakir

Applications and Applied Mathematics: An International Journal (AAM)

We investigate an efficient numerical method for the linear first-order Volterra integro-differential equations with integral boundary condition. To solve this problem, boundaries are determined for its derivative and the solution. The numerical solutions of the problem are modeled over a uniform mesh using the composite right-side rectangle concept for the integral component and the implicit difference rules for the differential component. Next, the stability and convergence of the numerical approach are discussed. The numerical experiments are presented confirming the accuracy of the proposed scheme.

Blend Matters: Interactions Of Rice Cultivars On Milling, Physico-Chemical & End Use Traits, Bindu Regonda

Graduate Theses and Dissertations

Rice blending or mixing of different rice cultivars, a common practice in the industry, significantly impacts processing efficiency and end-product quality, yet its effects on end products remain understudied. This research investigated the implications of blending contemporary Arkansas rice cultivars through two comprehensive studies focusing on milling yields and physicochemical properties, instantization, and parboiling processes. Five long-grain cultivars, including hybrids (RT 7521 FP, RT 7321 FP, XP 753) and purelines (Ozark, CLL 16), were blended in various combinations and different drying.

The first study revealed that blending significantly affected milling yields and physicochemical attributes. Pre-drying blending yielded better results compared …