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Dominant Tree Species As A Driver Of Forest Herb Community Assembly: The Peculiar Case Of Pawpaw (Asimina Triloba), Anna Wassel

Arts & Sciences Graduate Student Theses and Dissertations

Understanding the drivers of community assembly is a key goal in ecology and conservation. One way to better understand community assembly is to understand how the presence or absence of dominant species– highly abundant species with a proportionally large effect on the ecosystem–affects assembly. This approach allows for a more generalized understanding of community assembly based on the presence or abundance of one species rather than pairwise interactions among all species in a community. In forests, studies on dominant tree species have focused on how they affect patterns of species diversity. In contrast, surprisingly little is known about how dominant …

Asymmetric Fgf Receptor Dimerization: Implications For Fgf23 Biology And Drug Discovery, Mohammed S. Razzaque, Moosa Mohammadi

School of Medicine Publications

Fibroblast growth factor 23 (FGF23) requires both αKlotho and heparan sulfate proteoglycans (HSPGs) as obligatory coreceptors to bind, dimerize, and activate its FGF receptors (FGFRs) in the kidney, thereby regulating mineral ion and vitamin D homeostasis. Cryogenic electron microscopy studies reveal that FGF23 signaling proceeds through an asymmetric 1:2:1:1 FGF23–FGFR–αKlotho–HS assembly. According to this structural model, αKlotho simultaneously anchors FGF23 and one FGFR chain, referred to as the primary receptor (FGFRP), to form a 1:1:1 FGF23-FGFRP-αKlotho triplex, which boosts FGF23-FGFRP interaction. Subsequently, the HS coreceptor aids the triplex in recruiting a second FGFR chain, or secondary receptor (FGFRS), leading to …

Cardiac And Coronary Hemodynamics: Using An Integrated Ex-Vivo Beating Heart Experiments And Computational Modeling, Chenghan Cai

Master's Theses (2009 -)

Cardiovascular function arises from the complex interactions among the heart, the arterial system, and the coronary circulation. Questions such as how variations in left ventricular (LV) loading conditions affect LV and aortic functions through LV–aorta interactions; and how coronary artery diseases, such as stenosis, impact cardiac function and myocardial perfusion including left and right coronary perfusion via LV–coronary interactions, remain understudied. To answer these questions, this thesis focuses on two core objectives: (1) investigate the effects of LV loading conditions on LV and aortic functions through LV–aortic interactions by performing ex-vivo beating rat heart experiments, and (2) elucidate the impact …

In Silico Investigations Of Class Ii Trans Activator (Ciita): Its Plausible Implications In Neuroinflammation And Neurological Disorders, Kishore N

Theses and Dissertations

Inflammation plays a significant role in maintaining homeostasis. Neuroinflammation is a chronic inflammatory response in the central nervous system (CNS), leading to brain or spinal cord dysfunction. To promote mental health, it is crucial to understand the regulation of neuroinflammation. Class II transactivator (CIITA) is a master-regulator of the major histocompatibility complex II (MHCII).

Modulation of CIITA has been suggested as a promising intervention for inflammatory conditions, including neurological disorders. However, there is limited knowledge about the role of CIITA and its interactors in inflammation. This study aimed to understand the role of CIITA in neuroinflammation and neurological disorders using …

3d Bioprinting On Electrospun Nanofibrous Scaffolds To Fabricate Myocardial Patches, Muthu Parkkavi S

Theses and Dissertations

Tissue-engineered three-dimensional (3D) myocardial patches offer superior and innovative treatment strategy for myocardial infarction (MI). Among the various scaffold fabrication techniques, electrospinning and 3D bioprinting have received great attention due to their ability to recreate native cardiac tissue mimetic characteristics. Despite several advantages, electrospun nanofibers have limitations in cell delivery due to random cell seeding, while bioprinting faces challenges in creating hydrogel constructs with ideal mechanical properties capable of supporting cardiac contraction/relaxation cycle. Hence in this work, hybrid myocardial patches were developed by converging electrospinning and bioprinting techniques.

Electrospinning of PLCL:PEOz (B73, 7:3 blend of poly-L-lactide-co-ε-caprolactone (PLCL) and polyethyl oxazoline …

Biogenic Calcite Precipitation For Coastal Sand Stabilization: A Synergistic Approach Using Marine Bacteria And Natural Fibers, Aparna Gs

Theses and Dissertations

Coastal erosion, driven by natural forces such as waves, tides, winds, and currents and further intensified by anthropogenic activities like urbanization, climate change, and coastal infrastructure development, poses a significant threat to shoreline stability. Conventional erosion control methods, including jetties, embankments, and artificial reefs, often face limitations in sustainability and effectiveness. In this context, microbially induced calcite precipitation (MICP) has emerged as a promising ecofriendly solution for ground stabilization.

The present study investigates the potential of an indigenous ureolytic marine bacterium, Bacillus sp. N₉, isolated from the coastal sediments of Nagapattinam, Tamil Nadu, for coastal sand stabilization. The strain was …

Fabrication Of Protein-Based Nanomicelle Against Inflamed Synoviocytes In Rheumatoid Arthritis, Madhumithra Thangadurai

Theses and Dissertations

Rheumatoid arthritis (RA) is a chronic autoimmune disease marked by persistent synovial inflammation, progressive cartilage and bone destruction, and systemic complications. 1% of the global population are affected by RA, when their immune system targets synovial tissues, leading to joint pain, swelling, and functional disability. Standard treatments, such as disease-modifying antirheumatic drugs (DMARDs) like methotrexate (MTX), are limited by systemic toxicity and inconsistent patient responses, highlighting the need for improved therapies. This research work explores protein-glycosaminoglycan nanomicelles engineered using Zein with Chondroitin or carboxymethylated Dextran Sulfate as targeted drug delivery vehicles for RA.

MTX was encapsulated within these nanomicelles to …

Genomic Surveillance Of Indian Klebsiella Pneumoniae And Exploration Of Resistance Inhibitors, Abhirami Ks Ms

Theses and Dissertations

Klebsiella pneumoniae is an important ESKAPE pathogen that causes life threatening infections. The strains exhibiting multidrug-resistance (MDR) and hypervirulence are the priority pathogens for which immediate treatment and dissemination prevention strategies are required. To address this, genome profiling was performed to understand the AMR patterns, role of episomes, phages, virulence determinants and its association with sequence types.

The study includes 267 publicly available Indian K. pneumoniae genomes over a period of ten years and four sequenced isolates. Whole genome analysis revealed the widespread presence of diverse β-lactamase genes, with β-lactam resistance being predominant. Genes such as blaCTX-M-15, blaTEM-1B and blaOXA-232 …

Understanding Salt Stress In Watermelon: Impacts On Plant Performance, Adaptive Solutions, And Future Prospects, Sukhmanjot Kaur, Milena Maria Tomaz De Oliveira, Amita Kaundal

Plants, Soils and Climate Student Research

Soil salinity stress, intensified by extreme weather patterns, significantly threatens global watermelon [Citrullus lanatus (Thunb.) Matsum & Nakai] production. Watermelon, a moderately salt-sensitive crop, exhibits reduced germination, stunted growth, and impaired fruit yield and quality under saline conditions. As freshwater resources decline and agriculture’s dependency on irrigation leads to soil salinization, we need sustainable mitigation strategies for food security. Recent advances highlight the potential of using salt-tolerant rootstocks and breeding salt-resistant watermelon varieties as long-term genetic solutions for salinity. Conversely, agronomic interventions such as drip irrigation and soil amendments provide practical, short-term strategies to mitigate the impact of salt …

Evaluation Of South Carolina’S Extension And Outreach Agents’ Knowledge Of Harmful Algal Bloom Management And The Impacts Of One-Day Training, George Strickland, Debabrata Sahoo, Michael Vassalos, Heather Nix, Sarah White

Journal of Extension

Harmful algal blooms (HABs) impact livestock producers. Most Extension agents have limited knowledge about HAB management. Our study goal was to assess agent readiness and training on HABs. We used data from in-person surveys of South Carolina (SC) Extension personnel. We examined how training influenced HAB knowledge using pre/post-tests. Training improved agent knowledge of HAB management, but water resource agents learned more. The results of this study can be used to identify Extension training shortfalls and drive policy to better prepare agents throughout the state. Further research should involve prioritizing additional extension topics and assessing knowledge in a similar manner.

Small Meat Processor Needs Are Similar Across Region, Jordan C. Wicks, Alexis Wivell, Thomas Archibald, David Gerrard

Journal of Extension

This needs-based assessment provides insight into the challenges of small meat processors in two regions of the US. On-line surveys were provided to processors and despite regional differences, data show approximately 70% of processors in each state find retention of skilled labor the greatest challenge in maintaining current levels of operation and impede future growth. These findings suggest educational and certification programing may help improve small processor viability and mitigate local food security concerns. Given the disparity in animal production and livestock availability between these diverse states but similarity in responses, we posit this information is translatable across the US.

Partial Budgets Quantify Economic Outcomes Of Soil Health Management For Farmers, Jessica A. Kelton, W. Archie Flanders, Emily P. Ball, Dianna K. Bagnall, C. Wayne Honeycutt

Journal of Extension

Implementation of soil health management systems, such as reduced tillage and cover cropping, can reduce soil erosion, increase water infiltration, and improve soil productivity. Adoption of these practices can also improve net farm income, but effects vary based on region, commodity, and production methods. A partial budget analysis approach was used to evaluate impacts of adoption of soil health management systems on profitability from a regional, on-farm, perspective. The approach provides farmers with a resource to support decisions when considering the adoption of soil health management systems.

Economic Analysis Of Stockers Grazing Botanically Diverse Summer Annual Pasture, Kelly M. Mercier, Christopher D. Teutsch, S. Ray Smith, Kenneth H. Burdine, Eric S. Vanzant, Edwin L. Ritchey

Journal of Extension

Economic analyses were performed to determine the feasibility of retaining weaned fall-born calves on summer annual pastures (a monoculture, a 3-species mixture, or a 12-species mixture). Average daily gain was reduced by 0.3 lbs/day in calves grazing the complex mixture in two out of three years. Enterprise budgeting illustrated that retaining calves on summer annual forages was not economical. Two-way net return tables indicated that this scenario would only be profitable when cattle prices are high and pasture establishment costs are low. Extension educators should be sure to emphasize the economic risks when discussing these systems.

Using Vegetation Communities To Compare Natural And Constructed Wetlands In The Red River Basin In Texas And Louisiana, Kennedi K. Davis

Biology Theses

Wetland vegetation provides an abundance of ecosystem services such as water quality regulation, flood control, and it provides habitat space for fish, amphibians, and macroinvertebrates. Not only that, but these plants also act as excellent indicators of wetland conditions as dominant vegetation types are often used as biological criteria for classifying wetlands and other habitats (Cowardin and Golet, 1995). This project will assess the structure of vegetation communities to determine how they differ in constructed and natural wetlands within the Red River drainage basin to see if Agricultural Conservation Easement Program – Wetland Reserve Easement (ACEP-WRE) constructed wetlands are effective …

Variation In Phenotype, Genotype, And Somatic Diversity Among Asexual Schmidtea Mediterranea Planarians, S. Kershenbaum, Danielle Ireland, Ziad Sabry , '20, Christina Rabeler, Vir Shetty , '22, A. Aboobaker, Eva-Maria S. Collins

Biology Faculty Works

Most multicellular life reproduces sexually, utilizing a single-celled stage that acts as a genetic bottleneck. This bottleneck limits the evolution of selfish cell adaptations by ensuring all cells descend from a single progenitor. We investigated an obligately asexual strain of Schmidtea mediterranea planarians that reproduces by self-bisection and lacks a single-cell bottleneck. Using 2.5 yearlong data on planarian reproductive behavior combined with genotyping, we revealed two previously undescribed genetically distinct substrains within the CIW4 strain. One substrain showed reduced fitness, which correlated with substantial losses of heterozygosity and increased somatic diversity. By genotyping consecutive head offspring over multiple generations, we …

Advance S In The Generation And Transport Behavior Of Secondary Hazards From Food Packaging Sterilization, Mengjia Ren, Ye Liu, Jinpeng Wang, Shuang Bi

Journal of Food Science and Biotechnology

Food packaging sterilization is an important technical means to avoid the spread of SARS-CoV- 2 and the cross-contamination of foodborne viruses.However,the secondary hazards generated after sterilization are complex and have different characteristics,and a wide range of factors affect the formation of these hazards.The studies about the migration behavior of secondary hazards from packaging materials to food remain to be reviewed.Therefore,the author systematically reviewed the correspondence between sterilization technologies and secondary hazards generated after food packaging sterilization,the characteristics of secondary hazards,the factors affecting the formation of secondary hazards,and the detection technologies of secondary hazards.By outlining the classical migration model,the author summarized …

Oral Administration Of Lacticaseibacillus Paracasei Ccfm 1433 Boosts Host Immunity To Prevent Candida Albicans Infections, Xinya Zhang, Qiuxiang Zhang, Xin Tang, Bingyong Mao, Jianxin Zhao, Shumao Cui

Journal of Food Science and Biotechnology

[Objective ] This study aims to explore the role of Lactobacillus in enhancing host immunocompetence and preventing vaginal infections with Candida albicans.[Method ] A human vaginal epithelial cell (VK2/E6E7 cell) model was employed to screen the most potent strain among ten vaginal Lactobacillus isolates in inducing the antimicrobial peptide LL- 37.A mouse model of vaginal infection with Candida albicans was established.The effects of oral administration of the selected Lactobacillus strain on vaginal mucosal immunity,systemic inflammatory balance,and vaginal microbiota homeostasis were systematically evaluated using hematoxylin-eosin (HE) staining,ELISA,qPCR,and 16S rRNA sequencing.[Result ] Both t he cell lysate and fermentation supernatant of Lacticaseibacillus …

Research Progress In Phytosterols (Esters ) And Their Application In Food, Shuang Mei, Huibing Luo, Tian Gan, Yonggang Qi, Chunmei Li, Chao Wang, Zao Liu

Journal of Food Science and Biotechnology

Phytosterols esters are a type of compound synthesized through the esterification reaction between phytosterols and fatty acids.To clarify the research and application of phytosterols (esters ),the author provided an overview of their structural characteristics,synthesis methods,and physiological functions.Additionally,it was elucidated that phytosterols (esters ),as functional food ingredients,play a significant role in reducing cholesterol levels and exhibiting antioxidant properties in the human body.By delving into the bioactivity of phytosterols (esters ) and enhancing peopl e’s awareness of their nutritional value,this study makes an outlook on the research and application prospects of phytosterols (esters ) in food,thereby providing a crucial theoretical basis for …

Establishment Of A Hplc-Ms/Ms Method For Determination Of Cethromycin Residue In Poultry Eggs, Chenyang Chang, Liangzi Wang, Le Wang, Kai Chang, Jiao Shan, Xiao Wang, Liqiang Guo

Journal of Food Science and Biotechnology

[Objective ] This study aims to establish a method for determining the residual amount of cethromycin in poultry eggs based on high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS ).[Method ] Four representative poultry eggs (chicken eggs,duck eggs,goose eggs,and quail eggs ) were selected as the research matrices.Cethromycin was extracted with Mcllvaine-Na 2EDTA buffer solution,purified by hydrophilic-lipophilic balanced polymer solid-phase extraction column (HLB ),separated by a C 18 column with 0.1% (volume fraction ) formic acid water and acetonitrile as the mobile phase,and determined by HPLC-MS/MS in the multiple reaction monitoring (MRM ) mode combined with an external standard method.[Result ] …

Bifidobacterium Adolescentis Fhnfq 5m4 Modulates Gut Microbiota And Alleviates Colitis In Mice, Yi Wang, Liming Huang, Xihua Yu, Liuruolan Li, Wenwei Lu, Hongchao Wang, Zhijian Zhang

Journal of Food Science and Biotechnology

[Objective ] This study aims to verify and screen the Bifidobacterium adolescentis strains with vitamin A (VA) metabolic capacity,and investigate their effects on colitis symptoms and gut microbiota in mice.[Method ] The VA metabolic capacity of a panel of Bifidobacterium adolescentis strains was evaluated through in vitro fermentation,and the strain with the highest VA metabolic capacity was ultimately selected.This strain was administered orally to mice with dextran sulfate sodium (DSS )-induced colitis for 6 consecutive days.After the intervention,histopathological changes in the colonic tissue were assessed,and the levels of intestinal injury markers in the serum and cytokines,antioxidant enzymes,and retinoic acid (RA) …

Diverse Cell Types Establish A Pathogenic Immune Environment In Peripheral Neuropathy, Julie Choi

Arts & Sciences Graduate Student Theses and Dissertations

Neuroinflammation plays a complex and context-dependent role in many neurodegenerative diseases. We identified a key pathogenic function of macrophages in a mouse model of a rare human congenital neuropathy in which SARM1, the central executioner of axon degeneration, is activated by hypomorphic mutations in the axon survival factor NMNAT2. Macrophage depletion blocked and reversed neuropathic phenotypes in this sarmopathy model, revealing SARM1-dependent neuroimmune mechanisms as key drivers of disease pathogenesis. In this study, we investigated the impact of chronic subacute SARM1 activation on the peripheral nerve milieu using single cell/nucleus RNA-sequencing (sc/snRNA-seq). Our analyses reveal an expansion of immune cells …

Rna’S Symphony: Harmonizing Splice Junctions And Exon Counts For A Novel Approach To Differential Splicing Analysis, Jelard Aquino

UNLV Theses, Dissertations, Professional Papers, and Capstones

Alternative Splicing (AS) plays a critical role in transcriptome complexity and cell-type-specific gene regulation, yet its analysis remains methodologically fragmented, especially in the context of noisy and sparse single-cell RNA sequencing (scRNA-seq) data. This dissertation addresses key computational challenges in AS detection by evaluating existing tools, developing integrative frameworks, and proposing new strategies for improving analysis accuracy in both bulk and single-cell contexts. In chapter 1, I present a comprehensive literature review of computational tools designed for detecting and quantifying AS from bulk and scRNA-seq data. This review outlines major methodological paradigms, including exon-based and splice junction-based approaches, and evaluates …

An Analysis Of The Influence Of Human Disease Pathogens On Core Behaviors Of The Black-Legged Tick, Emily F. Marinko

UNLV Theses, Dissertations, Professional Papers, and Capstones

Ixodes scapularis, the black-legged or deer tick, is a vector for several different disease-causing microbes, including the causative agent of Lyme disease. As such, it is a major health concern for people living within its range in the eastern half of the United States, a habitation area that is increasing due to climate change. Despite its medical relevance as a disease vector, there is still much to learn about the basic behavior of these arachnids in the wild. Thus, the major hypothesis of this thesis is that ticks that are infected with specific human disease-causing microbes behave differently than those …

Claudin-1-Mediated Signaling And Therapy Resistance In Colorectal Cancer: From Mechanism To Translation, Mark W. Primeaux

Theses & Dissertations

Colorectal cancer (CRC) remains a leading cause of cancer-related mortality, with metastatic cases showing poor response to chemotherapy due to both intrinsic and acquired therapy resistance. Claudin-1 (CLDN1), a tight junction protein, is overexpressed and mislocalized outside of tight junctions in CRC, where it contributes to an aggressive, metastatic phenotype. Although this causal relationship has been well established, the mechanisms by which CLDN1 promotes tumor progression were unclear due to its lack of intrinsic enzymatic activity. This dissertation investigates the molecular mechanisms through which CLDN1 drives oncogenic signaling, its role in therapy resistance, and its translational potential as both a …

Scientist Perspectives: A Correlation Analysis Of Translational Science Competencies Compared With Principles Of Engagement And Knowledge Integration, Rachel Wenzl

Theses & Dissertations

The competencies identified in the development of the “Fundamental Characteristics of the Translational Scientist” may not consider and fully integrate the concepts of knowledge integration and engagement, key components of the translational science spectrum. This gap may be widening and deepening the “valley of death” and exacerbating ongoing challenges in the field of translational science. This dissertation explored the association of knowledge integration, stakeholder engagement, and community engagement principles compared with translational science competencies.

Utilizing content review and a non-experimental, correlation study design, data were collected through a quantitative survey from adult research subjects all self-identified as a research investigator …

The Characterization Of Per- And Polyfluoroalkyl Substances (Pfas) In Nebraska Drinking Water And Human Health Impacts, Sarah Tucker

Theses & Dissertations

Per- and polyfluoroalkyl substances (PFAS) are synthetic compounds that have been detected in water sources of urban and rural environments with evidence of adverse human health effects from exposure. Humans are primarily exposed through ingestion of contaminated water and food. PFAS exposure has been linked to negative multi-system health outcomes (liver, kidneys, cardiovascular, reproductive, and immune). PFAS occur as persistent mixtures in environmental media with decades long consequences to water quality. While national agencies have launched large-scale PFAS water quality monitoring studies, limited data exists for contamination of rural water in Nebraska, especially private wells. The aims of this study …

Role Of Stabilin-1 Expressing Macrophages In Colorectal Liver Metastasis, Jampa L. Gurung

Theses & Dissertations

Colorectal cancer (CRC) is the 2nd most common cause of cancer-related mortality, primarily due to its spread to distant organs. Colorectal liver metastasis (CRLM) is the foremost form of CRC spread due to the anatomical link between the liver and intestine. Despite advancements in diagnostic tools and adjuvant therapies, the survival rate of CRLM remains low, indicating the significant need to identify targetable mechanisms. Stabilin-1 (STAB1), a scavenger receptor expressed on tumor-associated macrophages, has been linked to tumorigenesis and poor outcomes in various cancers. However, the role of STAB1 in CRLM is not known. Here, we investigated the role of …

Exploring The Processing Of Objects, Settings, And Global Properties In Natural Auditory Scenes, Margaret A. Mcmullin

UNLV Theses, Dissertations, Professional Papers, and Capstones

Our auditory system has a remarkable ability to make sense of complex environments, allowing us to identify what we are hearing and where sounds come from. This process of auditory scene analysis is essential for situational awareness, decision-making, and effective communication in daily life. While much is known about how listeners segregate and identify individual sound sources (e.g., voices), less is understood about how global properties of a scene (e.g., openness, naturalness) contribute to perception. This dissertation examined how object- and setting-level information in natural auditory scenes are processed, and whether they rely on distinct or overlapping mechanisms. In Experiment …

Isolation And Divergence Of Greater Earless Lizards (Phrynosomatidae: Cophosaurus) In Western North America Support Multiple Diversification Processes And A Complex Demographic History, Christopher Robert Blair, Carlos Joaquín Pavón-Vázquez, Qaantah Rana, Keaka Farleigh, Erika Crispo, Thomas Panzera, Felipe De Medeiros Magalhães, Britt White, Uri Omar Garcia-Vazquez

Publications and Research

The Southwestern US and northern Mexico continue to serve as ideal regions to elucidate the suite of ecological and evolutionary processes influencing lineage diversification. The complex geological history of arid North America, coupled with paleoclimate change during the Pleistocene and diverse ecoregions makes a multipronged approach to hypothesis testing necessary. We combine thousands of loci from a genotyping-by-sequencing (GBS) approach along with mitochondrial DNA (mtDNA) sequences from the Greater Earless Lizard (Cophosaurus texanus) to examine diversity and test for cryptic population structure. We also apply recently developed coalescent approaches in a Bayesian framework to estimate migration rates. Population …

Lipidomic And Proteomic Insights From Extracellular Vesicles In The Postmortem Dorsolateral Prefrontal Cortex Reveal Substance Use Disorder-Induced Brain Changes, Chioma M Okeoma, Wasifa Naushad, Bryson C Okeoma, Carlos Gartner, Yulica Santos-Ortega, Calvin Vary, Savio Lima-Bastos, Victor Corasolla Carregari, Martin R Larsen, Alessio Noghero, Consuelo Walss-Bass, Rodrigo Grassi-Oliveira

Faculty, Staff and Student Publications

Substance use disorder (SUD) significantly increases the risk of neurotoxicity, inflammation, oxidative stress, and impaired neuroplasticity. The activation of inflammatory pathways by substances may lead to reactive astrogliosis and chronic neuroinflammation, potentially mediated by the release of extracellular particles (EPs), such as extracellular condensates (ECs) and extracellular vesicles (EVs). These particles, which reflect the physiological, pathophysiological, and metabolic states of their cells of origin, might carry molecular signatures indicative of SUD. In particular, our study investigated neuroinflammatory signatures in SUD patients by isolating EVs from the dorsolateral prefrontal cortex (dlPFC) Brodmann's area 9 (BA9) from postmortem subjects. We isolated BA9-derived …