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Two Analytic Issues Arising From Models In Probability And Materials Science, Giang Vu Thanh Nguyen

Mathematics & Statistics Theses & Dissertations

This dissertation explores two distinct topics centered on mathematical models in probability theory and materials science. The first part investigates a series of functions derived from an adaptive algorithm designed to address the score-based secretary problem, a classic challenge in probability theory. This problem involves making immediate decisions to select the best candidate from a sequence of interviews. The algorithm aims to maximize the probability of selecting the optimal candidate based on observed scores. We prove two fundamental analytic properties of this sequence of functions as a theoretic support of the algorithm: first, the functions in the sequence each possess …

Systems Statistical Engineering – Hierarchical Fuzzy Constraint Propagation, Hengameh Fakhravar

Engineering Management & Systems Engineering Theses & Dissertations

Driven by the growing need in the 21st century for integrating rigorous statistical analysis into engineering research, there is a movement to develop an integrated statistical engineering science within statistics and quality communities (Hoerl & Snee, 2010; Anderson-Cook et al., 2012). Systems Statistical Engineering research seeks to integrate the Causal Bayesian hierarchical modeling (Pearl, 2009) and cybernetic control theory within Beer’s Viable System Model (1972, 1979, 1985) and the Complex Systems Governance framework (Keating, 2014; Keating & Katina, 2015, 2016) to produce multivariate systemic models for robust dynamic systems mission performance. Cotter & Quigley (2018) set forth the Bayesian systemic …

A Strict Physicality-Preserving Scheme For A 2d Q-Tensor Flow With A Singular Potential, Md Mashud Parvez

Mathematics & Statistics Theses & Dissertations

Nematic liquid crystals are a state of matter that exhibit properties between those of conventional liquids and solid crystals. Their unique ability to align molecules in specific directions makes them essential in various applications, including display technologies and advanced materials. To model their complex behavior, mathematical frameworks such as the Q-tensor model are used to describe the orientation and degree of molecular order. In this work, we introduce a numerical scheme for a two-dimensional (2D) dynamic Q-tensor model, which is formulated as an L²-gradient flow driven by the liquid crystal free energy and incorporates a singular potential to …

From First-Generation To Flourishing: Exploring The Influence Of Academic, Social, And Deeper Life Interactions In Higher Education, Melissa Jean Overton

Educational Leadership & Workforce Development Theses & Dissertations

Despite comprising half of all undergraduate students (RTI International, 2024) and being widely studied in higher education literature, first-generation students experience many barriers to success and are less likely to graduate than continuing-generation students (Engle & Tinto, 2008; Fry, 2021; Kezar et al., 2023). Social science and higher education scholars have identified flourishing, the presence of complete mental health and holistic well-being (Keyes & Haidt, 2003), as an important outcome of higher education beyond more traditional success metrics, with the thought that flourishing promotes success in other areas.

This study explored how first-generation students’ academic, social, and deeper life interactions …

Towards Improving Computational Modeling Of The Lumbar Spine - Impact Of Material Properties And Laminotomy On Spinal Biomechanics, Isaac K. Kumi

Mechanical & Aerospace Engineering Theses & Dissertations

Spinal ligaments play a crucial role in maintaining the mechanical stability of the lumbar spine. These dense, collagenous tissues not only resist excessive motion but also distribute loads between spinal components to protect neural structures. Traditionally, the mechanical response of ligaments has been modeled using linear elastic assumptions, which treat the tissue as having a constant stiffness regardless of loading history. While this simplifies analysis, it fails to capture the time-dependent behaviors, such as creep, stress relaxation, and hysteresis, that are characteristic of biological tissues.

Viscoelastic modeling may provide a more physiologically accurate representation by incorporating both elastic and viscous …

Advanced Analytical Biosensing For Cancer Detection And Neural Diagnostics Using Tapered Optical Fiber (Tof), Protonic, And High Throughput Microplate –Based Technologie, Bayan Hassan Alharbi

Chemistry & Biochemistry Theses & Dissertations

This dissertation investigates the development and application of advanced biosensing technologies to enhance early disease detection, neurological diagnostics, and bioactive compound evaluation. The research spans four key areas. First, it introduces tapered optical fiber (TOF)-based plasmonic biosensors for the non-invasive detection of prostate cancer, demonstrating high sensitivity and specificity compared to conventional diagnostic methods.

Second, it explores the use of fluorescent biosensors to test the Transmembrane Electrostatically Localized Proton (TELP) theory, shedding light on the role of localized protons in neuronal signaling and energy transfer. Third, the work presents a high-throughput, microplate-based biosensing platform for analyzing mitochondrial function under nanosecond …

Inter-Cellular Forces Modulate Cell-Ecm Traction Forces, Zaria Booth

Mechanical & Aerospace Engineering Theses & Dissertations

Epithelial cells are among the most abundant cell types in the human body, making up sheets of epithelial tissues that cover the linings of organs and body cavities. Cellular adhesion and force transmission across epithelial tissues are crucial in maintaining tissue integrity and ensuring proper tissue regeneration. Defects in cellular force transmission have been found in various diseases, including cancer. Force transmission at cell-cell and cell-ECM junctions drive cell survival and development. It has been previously shown that changes in cell-ECM traction directly modulates forces at cell-cell contacts. In this study, we aim to determine the effects of perturbations in …

Learning Regulatory Dna-Sequence Code Of Epigenetic Events Using Deep Neural Networks, Sanjeeva Reddy Dodlapati

Computer Science Theses & Dissertations

Epigenetic events, such as DNA methylation and histone modifications, arise from a complex interplay among genomic sequence, chromatin-remodeling factors, and environmental cues. These regulatory mechanisms can induce changes in gene expression without altering the underlying DNA sequence, playing critical roles in development, disease, and cellular differentiation. Among these events, DNA methylation is frequently profiled using bisulfite sequencing (e.g., whole-genome bisulfite sequencing [WGBS], reduced representation bisulfite sequencing [RRBS]). However, predictive modeling of epigenetic states—including methylation patterns and regulatory variant effects—remains challenging due to data sparsity, label noise, and limited uncertainty estimation in current deep learning approaches. This dissertation addresses these issues …

The Influence Of Monsoon Variability On The Circulation Of The Near-Surface Indian Ocean And The Depth-Integrated Chlorophyll, Marufa Ishaque

OES Theses and Dissertations

The Indian Ocean experiences a strong semiannual reversal of monsoon winds, which determines the weather and climate of Asia, including freshwater fluxes between the atmosphere, land, and ocean. Studies and model projections suggest that the timing and intensity of the seasonal monsoon have already started to change, with more dramatic changes likely in the future. However, the impact of these changes on the Indian Ocean circulation system, including the inter-basin salt/freshwater transport between the Bay of Bengal and the Arabian Sea, remains unclear. To better understand how monsoon variability affects Indian Ocean circulation patterns, a Regional Ocean Modeling System simulation …

Intersecting Realities And Evolving Landscapes: Mapping Generative Ai Within The Framework Of Digital Rhetoric, Joshua Troy Nieubuurt

English Theses & Dissertations

The increased usage of [Generative] AI technologies (GenAI) in the 21st century has called into the question the rhetorical agency of these digital things. [Gen]AI has historically been framed within a Heideggerian “readiness-to-hand” dynamic in which it has been unilaterally conceived as a tool to be used by humans. This dissertation proposes that the GenAI assemblage is capable of being a co-actor in rhetorical spaces. To provide evidence for this stance This dissertation utilizes Actor Network Theory to map the actants within a GenAI assemblage. In doing so it allows for an understanding of the stakeholders (both human and non-human) …

Career Pathways Program Annual Report For Ay 2024/25, Wie Yusuf

Career Pathways

Career Pathways launched in August 2017 as the university-wide initiative to provide professional development to graduate students. It encompasses both the Preparing Future Faculty (PFF) and the Preparing Future Professionals (PFP) Certificates. The Preparing Future Faculty Certificate was established in 2007, while the Preparing Future Professionals Certificate was launched in 2017, concurrently with the introduction of Career Pathways. The Career Pathways program prepares graduate students for a successful transition into thriving careers. With the PFP Certificate, specifically, the emphasis has been on filling the existing gap in career and professional development for master’s students and doctoral students with career plans …

Monarch: Old Dominion University Magazine, Victoria Bourne (Editor)

Monarch Magazine

Summer 2025 issue of Monarch, the Old Dominion University Magazine.

Subtitled: GLOBAL IMPACT: Monarchs Make a Difference by Land and by Sea

The Relationships Between Expectancy-Value Beliefs, Communal Value Beliefs, Family Identity, And Academic Persistence Among First- And Continuing-Generation College Students, Douglas W. Snuffer

STEMPS Theses & Dissertations

First-generation college students (students for whom neither parent has a 4-year college degree) have lower college graduation rates than their continuing-generation peers (Cahalan et al., 2021; Fry, 2021). First-generation students may experience barriers to higher education, leading to lower levels of academic achievement motivation for college. Two of these barriers may include 1) cultural mismatch (Stephens, Fryberg, et al., 2012) with colleges via communal value (a value set that emphasizes community and family over the self) and 2) a strong sense of family identity, which lends itself to perceived family obligations (Fuligni et al., 2007). To examine the relationships between …

Using Radium Isotopes To Compare Nutrient Inputs Via Submarine Groundwater Discharge To Offshore Export On The West Florida Shelf, Andrew L. Lindgren

OES Theses and Dissertations

Radium isotopes have been used to trace submarine groundwater discharge (SGD) and associated nutrient and metal inputs into the coastal ocean. They have also been used to estimate rates of diffusive mixing and export fluxes of dissolved constituents offshore. However, use of both approaches in tandem to determine the fate of groundwater inputs after they enter the coastal ocean is still relatively unexplored. Radium isotopes and nutrients were measured in two cross-shelf cruises on the West Florida Shelf in different seasons and in quarterly sampling of offshore wells. Through 226Ra mass balance and 223Ra-derived diffusive mixing rates, inputs of nutrients …

Examination Of An Experimental Paradigm Of Impaired Control Over Alcohol Use, Emily K. Junkin

Psychology Theses & Dissertations

Alcohol use disorders peak during young adulthood with nearly 27% of individuals aged 18 to 30 meeting diagnostic criteria. Impaired control, or difficulty limiting alcohol use, has been identified as one of the earliest symptoms of an alcohol use disorder and is predictive of alcohol use severity. Despite the relevance of impaired control for identifying and preventing hazardous drinking behaviors, there is a dearth of research that exists on this critical risk factor. The current study tested an experimental paradigm of impaired control whereby participants self-administered alcohol following guidelines to limit consumption to a low level. It was hypothesized that …

Understanding Anti-Racism In Counselor Education: A Narratology Of Anti-Racist Pedagogy In Sociocultural Courses, Danielle G. Rodgers

Counseling & Human Services Theses & Dissertations

Counselors have the privilege to join children, adolescents, and adults from all walks of life in a journey of working towards mental and emotional wellness. Our code of ethics outlines “honoring diversity and embracing a multicultural approach in support of the worth, dignity, potential, and uniqueness of people within their social and cultural contexts” (p.3) and promoting social justice as two of our core professional values (American Counseling Association [ACA], 2014). The ACA also stated in their Antiracist Statement in 2020 that “we have a moral and professional obligation to deconstruct institutions which have historically been designed to benefit White …

Investigating The Ability To Perceive Nonverbal Behaviors In Different Interaction Formats, Amanda J. Ashdown

Psychology Theses & Dissertations

The rapid rise in interactive video-based communication has raised important questions about how it affects the perception of nonverbal behavior and impression formation. Guided by the Parallel Process Model (PPM), Multiple Resource Theory (MRT), and Working Memory (WM) models, this study investigated the ability of individuals to observe and assess another person’s nonverbal behaviors and form accurate impressions during conversations in live, face-to-face interactions compared to virtual formats. The study employed a 2 (interaction format: live vs. virtual; within-subjects) × 2 (observation type: active vs. passive; between-subjects) × 2 (genuineness: genuine vs. nongenuine behavior; between-subjects) mixed design. Participants either actively …

Millennial And Gen-Z Experiences In Healthcare And Education In The Us, Zabia Evans, Anastasia Raymer, Beverly Khabo

Graduate Student Government Association Research Conference

In the United States, healthcare and educational institutions have a deep-rooted history of discrimination based on race, ethnicity, and other demographic factors, resulting in unequal access to services and mistreatment of minority populations. This history extends to the field of speech-language pathology, with disparities in service being cited in the literature due to lack of clinician knowledge, non-diverse standardized testing measures, lack of resources and support, among other factors. Policies and legislation in recent decades have attempted to address these serious issues. This survey research investigates the childhood healthcare and educational experiences of individuals born during or after 1981, focusing …

The Evolution Of Russian And Chinese Disinformation Tactics And The Threat They Pose To The U.S. Cybersecurity, Jehovani Sese

Cybersecurity Undergraduate Research Showcase

This paper aims to discuss how disinformation has become the most powerful tool used against the United State by foreign operatives. Of these foreign operatives, Russia and China have shown the ability to use advanced tactics to truly affect the United States security. Often these tools came in the form of state-sponsored media, influence campaigns and fake online identities. This literature review explores the evolution of Russian and Chinese disinformation tactics, examining how these approaches have changed over time and become more sophisticated. This paper will highlight major campaigns which use tools such as bot networks, and social media manipulation. …

17 - Mapping The Spatial Distribution Of Submerged Aquatic Vegetation Using Commercial Satellite Imagery, Brandon Watson

Undergraduate Research Symposium

Seagrass in the Chesapeake Bay has seen an increase due to restoration efforts since the 90s, but with the extreme change of climate, we are unsure if the seagrass will thrive or perish, and where it will occur in the bay. Seagrass stabilizes coastal sediments, reducing erosion and protecting shorelines. It provides crucial habitats and nursery grounds for a diverse range of marine species, supporting both biodiversity and fisheries. Additionally, they play a significant role in carbon sequestration, which mitigates the effects of climate change. This study specifically looked at the area from the mouth of the Rappahannock River up …

05 - Freeze Severity And Black Mangrove Growth: Influence Of Plant Origin On Side Shoot Development, Kathryn Bourlier, Katelyn Overstreet, Erik Yando

Undergraduate Research Symposium

Despite a reduction in freeze events and subsequent expansion in the southeastern US, freeze impacts still play a critical role in mangrove morphology and local range limits. Freeze events can impair growth, limit survival, and commonly prompts side shoot development. This study examines the relationship between plant origin, freeze severity, and side shoot development in black mangroves. Our findings show that plants from each location exhibited distinct morphological responses, with similarities more closely linked to environmental conditions rather than geographic proximity. Our work offers insights into thermal tolerance thresholds and implications for mangrove stature in coastal wetlands.

03 - Carbon Sequestration Of Nypa Fruticans And Metroxylon Sagu In Negros Oriental, Philippines, Sofia Baez, Dave Gauthier, Roy Olsen De Leon, Jeanette Mara Tan-Sumagaysay, Alicia Gotonero, Chris Bird

Undergraduate Research Symposium

Mangrove forests are highly productive biomes and important for many ecosystem services such as protecting against extreme weather conditions, providing a safe habitat for animals, and sequestering and storing carbon. Understanding carbon sequestration of mangrove systems can aid in understanding their capacity to buffer against climate change. In this study, we investigate the carbon potential of two mangrove palms native to Southeast Asia and Oceania: Nypa fruticans, the Nipa Palm, and Metroxylon sagu, the Sago Palm. In recent years, Nypa palm populations have declined due to their use in thatched roofing. The objective of this project was to investigate …

02 - Habitat Preference Of Ambrosia Beetles (Curculionidae) Using Bottle Traps In Southeastern Virginia, Sajrim Chowdhury, Morgan Harrison, Deborah A. Waller, Umme Akter

Undergraduate Research Symposium

Ambrosia beetles attack host trees by boring into the stem and infecting the tree with a symbiotic fungus. Infected trees suffer damage to the vascular system which often results in tree mortality. We examined whether different species of native and invasive ambrosia beetles prefer different habitats by placing bottle traps in riparian areas near streams and in forested habitats in several locations in southeastern Virginia. Numerous ambrosia beetles were collected in the traps, and we related ambrosia beetle species to the habitat in which it was collected.

Proceedings Of The 103rd Annual Virginia Academy Of Science Meeting, 2025, Virginia Academy Of Science

Virginia Journal of Science

Proceedings (abstracts) of the 103rd Annual Meeting of the Virginia Academy of Science, May 22, 2025, at the University of Virginia, in Charlottesville, Virginia.

Investigating The Demography And Parasites Of Spring-Migrating Cedar Waxwings (Bombycilla Cedrorum) In Virginia After A Single-Day Mortality Event, Karen E, Powers, William W. Sadler, Acalia J. Carter-Martin, G. Caleb Smith, Gabe W. Tieskotter, Katie E. Wheeler, Matthew T. Close, Sara O'Brien, Pavel B. Klimov, Andrew D. Sweet, Stephen A. Smith, Jamie K. Lau

Virginia Journal of Science

While investigating the cause of death in a cedar waxwing (Bombycilla cedrorum) mortality event in March 2024 in Roanoke, Virginia, we collected parasites, investigated gizzard contents, and described demography. The group of 20 was slightly male-dominated (12/20) and only contained two adults (after second year - both females). We recovered 46 ectoparasites from 16 of 20 individuals and reported two species of feather mites (Proctophyllodes ampelidis [N=37] and Analges integer [N=5]), one oribatid mite, two spider mites (order Trombidiformes), and one unknown mite (likely immature oribatid). We recovered no endoparasites. This mortality event provided a sample size …

In Memoriam: Dr. Arthur W. Burke, Jr., Richard Groover

Virginia Journal of Science

Recognition of the contributions of Dr. Arthur W. Burke, Jr. to the Virginia Academy of Science.

Program: Virginia Academy Of Science 103rd Annual Meeting, 2025, Virginia Academy Of Science

Virginia Journal of Science

Full program of the 103rd Annual Meeting of the Virginia Academy of Science. Held at the University of Virginia, Charlottesville, Virginia on May 22, 2025.

Valorization Of Industrial Wastes To Low-Carbon Minerals, Nandan Nag

Civil & Environmental Engineering Theses & Dissertations

This study concentrates on developing methods for utilizing industrial waste materials such as red mud and phosphate slag. In this study, an electrochemical process was developed for recovering iron metal powder from red mud. Red mud is a waste material from aluminum refineries. Although red mud can be utilized as a construction and building material, its use is becoming controversial due to its high metal content, which contributes to its toxicity. However, the high iron oxide content in red mud makes it a good feedstock for producing iron. In this project, we employed an electrochemical technique for extracting iron powder …

Network Analysis Of Sociotechnical Systems, Siva Kadiresan

Engineering Management & Systems Engineering Theses & Dissertations

Sociotechnical networks have become integral frameworks in the accomplishment of organizational objectives by increasingly diverse, cross-functional, and technology-enabled modern teams. In cross-disciplinary teamwork, multiple mediating and moderating factors appear to lend context to the effects of team diversity faultlines on team outcomes. In the several decades of research into teamwork from a network perspective, there has been a paucity of empirical studies that examine how team transition processes and cross-disciplinary connections influence the impact of faultlines on team performance. This study investigates the association among perceived teamwork effectiveness, transition processes, cross-functional team connections, and faultlines in the context of sociotechnical …

Modeling The Impacts Of Disruptive Events On Driving Behaviors, Transportation Safety, And Equity: Advanced Statistical Insights From The Covid-19 Pandemic, Xiaomeng Dong

Civil & Environmental Engineering Theses & Dissertations

This dissertation aims to understand how disruptive events —particularly the COVID-19 pandemic—affect driving behaviors, transportation safety and equity by leveraging advanced statistical modeling techniques and data from Virginia. This research pursues three overarching objectives. First, it employs multigroup structural equation modeling (SEM) to uncover the complex interrelationships among risky driving behaviors, injury severity, and pandemic-related factors, delineating the mechanisms through which COVID-19 has impacted crash outcomes via changing risky driving behaviors. Second, it leverages hidden Markov models to trace shifts in safety states over the pre-, during-, and post-pandemic periods, determining whether and when safety conditions return to pre-pandemic norms. …