Digital Commons Network^™

Effects Of Sediment Composition On Spartina Alterniflora And Juncus Roemerianus Productivity In Coastal Virginia: A Thin-Layer Sediment Placement Experiment, Caitlin Hemphill

Biological Sciences Theses & Dissertations

Climate change poses a major threat to the health of estuaries and their coastal wetland systems. The Chesapeake Bay’s coastal salt marshes are at high risk of inundation due to sea-level rise and land subsidence. Restoration techniques for maintaining coastal marsh resistance to sea-level rise are being developed and refined, with thin layer placement (TLP) emerging as a feasible solution in many areas of the United States. Despite TLPs use across the country, additional research is needed on species-specific responses, sediment types, and geographically focused studies in the lower Chesapeake Bay. My research addresses these gaps by combining both greenhouse …

Analysis On Plasma Propulsion Thruster Material Reconfiguration For Thrust Stabilization, Chinedumu Chidiebere Okafo

Mechanical & Aerospace Engineering Theses & Dissertations

Rocket propulsion has been a primary focus for scientific and technical advancement supporting space exploration. For long-duration, low-thrust space missions, propulsion systems designed with plasma energy as the primary source for generating thrust are of high interest. Plasma energy, like electric propulsion, involves the excited state of ionized atoms, where the ionized particles are separated and then act as a propellant to push a spacecraft in the intended direction for flight. Although more energy efficient compared to traditional rocket systems, plasma propulsion has the deficiency of consistent erosion of the metallic containment substrate, as plasma is being generated and released …

Good And Safe: Exploring The Impact Of Mindfulness And Primal World Beliefs On Psychological Well-Being, Katelyn J. Haschke

Psychology Theses & Dissertations

Dispositional mindfulness refers to the ability to intentionally focus on the present moment, which positively affects psychological well-being (PWB). Mindfulness can be practiced through formal interventions—such as meditation or body scan, where individuals engage in structured activities to cultivate awareness—or informal practices, such as focusing on one task at a time where mindfulness is integrated into routine activities. A person’s phenomenological perspective, shaped by their core beliefs about the world (primals), also influences PWB. For instance, those who view the world as mostly safe or good may be more likely to form close relationships and engage more deeply with their …

Practicing In The Laboratories Of Democracy: An Interpretive Phenomenological Analysis Of How Political Science Faculty Use Simulations With Community College Students, James Stewart Shifflett

STEMPS Theses & Dissertations

Political science faculty members have often used simulations to promote civic engagement and build political efficacy in students. However, the use of political simulations with community college students has not been studied as extensively as it has with their four-year counterparts. Through the interpretive phenomenological analysis (IPA) methodology, this study examined the experiences of nine political science faculty members who use simulations with community college students to understand how instructional designers might better support their civic engagement and design efforts. Faculty members who participated in the study use simulations as constructive social interactions; as comprehensive learning experiences integrating preparation, facilitation …

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 …

Analysis Of Multi Grade Deep Learning, Ronglong Fang

Mathematics & Statistics Theses & Dissertations

Multi-Grade Deep Learning (MGDL) is a training framework that incrementally builds deep neural networks. It does this by dividing the training process into multiple “grades,” where each grade sequentially trains a shallow neural network to learn the residue from the previous one, using the outputs of prior grades as input. This approach progresses from shallow to deep architectures. This dissertation offers a comprehensive theoretical and numerical analysis of the MGDL methodology.

We first demonstrate that MGDL can effectively learn target functions within the sum-composition learning format. In this context, MGDL approximates high-frequency components by composing multiple low-frequency functions. This unique …

Enhancing Non-Visual Interaction With Online User-Generated Content, Mohan Krishna Sunkara

Computer Science Theses & Dissertations

The Web has become the dominant medium for our everyday activities, including communication, business, e-commerce, news, and entertainment. Consequently, the online world is experiencing an explosion of User-Generated Content (UGC), particularly on social media platforms and online review systems. To facilitate convenient interaction with UGC, web platforms have adopted various presentation strategies that enable users to efficiently browse and contribute to the UGC. However, these user interfaces are primarily designed for sighted individuals, so they do little to assist blind users who rely predominantly on audio-based screen reader assistive technology. The extant efforts to improve web interaction for blind users …

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 …

Testing An Ironic Process Model Of Emotion Expression In Daily Life, Laura B. Kenneally

Psychology Theses & Dissertations

Expressive suppression, or suppressing the expression of an emotion, is a common emotion regulation approach that has been found to have substantial negative implications for one’s mental health, physical health, and relationship functioning. However, expression of emotion, and of negative emotion in particular, has not consistently been found to be beneficial for mood or relationships. Moreover, the social expression of emotion that is culturally valued among Black-identifying Americans is different in White-identifying Americans, particularly in regard to expression of negative affect. However, it is unknown whether this cultural context mitigates the potential consequences of expressive suppression and emotion expression.

Expressive …

School Counselor Burnout And Self-Efficacy And Their Impact On The Degree Of Implementation Of A Comprehensive School Counseling Program, Rebecca Pierre-Louis

Counseling & Human Services Theses & Dissertations

School Counselors are educators who are vital in supporting students’ educational development. School Counselors do this by delivering a comprehensive, developmentally appropriate, and prevention-oriented school counseling programs that provide direct, indirect, and responsive services to support students’ career, academic, and social/emotional development. School Counselors do this while often experiencing an expanded definition of their role within a school building. While research supports the benefits of comprehensive school counseling programs to schools and students, school counselors often face large student caseloads. As well, they are tasked with many non-school counseling duties, which hampers the delivery of a comprehensive school counseling program. …

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 …

Reproductive Redlining: Unraveling Historical Disparities And Facility Placement In Distance To Licensed Childcare Facilities, Reproductive Health Clinics, & Crisis Pregnancy Centers For Women In The Southern Region Of The United States, Mackenzie A. Kibler

Sociology & Criminal Justice Theses & Dissertations

This dissertation investigates how historical and structural inequalities shape contemporary access to reproductive health services, licensed childcare facilities, and crisis pregnancy centers across Mississippi, Virginia, and Maryland. Using feminist geography, reproductive justice theory, and historical trauma theory, this research develops the concept of reproductive redlining to explore how race, policy, and space intersect to produce health disparities. By combining GIS mapping with multivariate statistical analysis and redlining data from the Home Owners’ Loan Corporation (HOLC), the study evaluates spatial distributions and demographic correlates of facility access before and after the Dobbs decision. Findings reveal enduring spatial inequities that disproportionately impact …

'Managed Hearts’ In Helper-Education: Gender Non-Binary Helper-Educators’ Experiences Of Emotional Labor, Jordan Pearce

Counseling & Human Services Theses & Dissertations

The unique experiences of people who identify with a gender beyond the binary paradigm dominant in the Global West are not well understood. The literature provides little insight into the experiences and perspectives of these individuals in a variety of contexts, including in their workplaces. As various social movements collide, they bring amplified attention to the mental health of marginalized communities and to workers, as well as the dynamics of modern work environments, and the specific needs of certain individuals doing certain types of work. The current study explored the experiences of gender non-binary individuals (GNI) working as helper-educators engaged …

Influence Of Mixing Duration And Absorption Characteristics Of Superabsorbent Polymers On The Fresh And Hardened Properties Of High-Performance Concrete, Yu Cun Gu, Kamal H. Khayat

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This study investigates the combined influence of superabsorbent polymers (SAPs) with distinct absorption kinetics and extended mixing sequences on the rheological, mechanical, and transport properties of high-performance concrete (HPC). Two SAPs—an ionic acrylamide-co-acrylic acid copolymer (SAP-P) and a non-ionic acrylamide polymer (SAP-B)—were incorporated at an internal curing level of 100%. The impact of extended mixing times (3, 5, and 7 min) following SAP addition was systematically evaluated. Results showed that longer mixing durations led to increased superplasticizer demand and higher plastic viscosity due to continued water absorption by SAPs. However, yield stress remained relatively stable owing to the dispersing effect …

Role Of Cellular Proteins In The Regulation Of Herpes Simplex Virus Type 1 Gene Expression And Dna Replication, Joseph R. Heath

Electronic Theses and Dissertations

Herpes simplex virus type 1 (HSV-1) is a ubiquitous human pathogen that infects the majority of the human population. To facilitate infection, this virus relies on a combination of host and viral factors. Previous studies have revealed a number of host proteins that associate with the HSV-1 genome throughout infection but their putative role(s) in this process remain undefined. This study aims to examine two such proteins to determine their contributions to HSV-1 gene expression and DNA replication. The first of these factors is Ints3, a subunit of the Integrator complex. This protein complex functions in transcription regulation, and Ints3 …

How Dust Impacts Galaxy Evolution In The Early Universe With Champs: Data Reduction And Source Detection, Felix Martinez

Theses

How dust impacts galaxy evolution in the early universe is largely unconstrained due to under sampling in the rest-frame far-IR. New detections of optically dark galaxies (galaxies that have no rest-frame optical counterparts) have shown that there is a population of galaxies that have largely gone undetected due to this under sampling. CHAMPS (PI: A. Faisst) is designed to study how dust impacts galaxy evolution in the early universe by complimenting MIRI and NIRCam observations from JWST in COSMOS-Web and PRIMER with new ALMA observations focused at 1.2 mm (ν = 250 GHz). This thesis presents the data reduction and …

Modification Of Tini Alloy By Fast Pulse Laser Heat Treatment, Yitao Chen, Mohammad Masud Parvez, Frank Liou

Mechanical and Aerospace Engineering Faculty Research & Creative Works

In this study, the effects of local heat treatment with fast pulse laser on thin TiNi shape memory alloy strip materials were investigated. Various materials characterization methods including optical microscope, scanning electron microscope, atomic force microscope, X-ray diffraction, differential scanning calorimetry, and Vickers hardness were used to identify the differences of microstructure, mechanical properties, and functional properties between regions inside and outside the laser-scanned region. The tensile test was also conducted for both the non-laser-scanned specimen and the laser-scanned specimen. The area covered by laser scanning shows great differences by possessing a more homogeneous austenite phase without shear bands and …

Digital Twins, Ai, And Cybersecurity In Additive Manufacturing: A Comprehensive Review Of Current Trends And Challenges, Md Sazol Ahmmed, Laraib Khan, Muhammad Arif Mahmood, Frank Liou

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The development of Industry 4.0 has accelerated the adoption of sophisticated technologies, including Digital Twins (DTs), Artificial Intelligence (AI), and cybersecurity, within Additive Manufacturing (AM). Enabling real-time monitoring, process optimization, predictive maintenance, and secure data management can redefine conventional manufacturing paradigms. Although their individual importance is increasing, a consistent understanding of how these technologies interact and collectively improve AM procedures is lacking. Focusing on the integration of digital twins (DTs), modular AI, and cybersecurity in AM, this review presents a comprehensive analysis of over 137 research publications from Scopus, Web of Science, Google Scholar, and ResearchGate. The publications are categorized …

Examining The Impact Of A Utility Value Intervention On Self-Regulated Learning Engagement, Wanda D. Brooks

STEMPS Theses & Dissertations

The purpose of this study was to examine the impact of inserting a motivation intervention into a self-regulated learning training in an introductory biology course to increase academic performance and persistence to degree completion in science. The study was an experimental design with pre- and post-tests, with treatment and comparison groups. The training was in the form of three self-regulated learning cycles presented to students on a Blackboard Organization site where students were asked to record self-regulated learning activities in a journal during training. The primary aim of the intervention was to increase engagement in the self-regulated learning training by …

Valorizing Cement Kiln Dust And Glass Powder: A Binder Study On Sustainable Partial Cement Replacement, Sai Kiran Simhadri

Civil & Environmental Engineering Theses & Dissertations

The production of cement ranks as a major source of global CO₂ emissions because of the high energy requirements needed to create clinker. The construction industry is actively seeking ways to reduce its carbon footprint. Utilizing industrial waste materials to partially replace cement can lower emissions. This research evaluates a ternary binder system which uses Cement Kiln Dust (CKD) and Glass Powder (GP) to replace a portion of Type IL (Portland Limestone) cement. The mixes were made with a fixed water-to-binder ratio of 0.44 and contained 15% GP by mass while the CKD content ranged from 0% to 10%. The …

Enhancing The Design Of Strained Superlattice Gallium Arsenide Based Photocathodes With Distributed Bragg Reflector, Adam D. A. Masters

Electrical & Computer Engineering Theses & Dissertations

Particle accelerators play a crucial role in our understanding of matter and the universe and have numerous practical applications in various fields. These devices enable scientists to examine the smallest components of matter, study the forces that govern their interactions, and probe conditions from the early universe. Moreover, accelerators are valuable in medicine, industry, and research, enhancing imaging methods, cancer therapies, and manufacturing techniques. As the experiments conducted at these facilities evolve and require higher precision, improved particle sources must continue to advance to keep up with their requirements. To do that, we enhanced the design of spin polarized electron …

An Optimized Generalized Multi-Color Point Implicit Solver For Intel Gpus Using Intel Oneapis Esimd, Joseph Wassell

Computer Science Theses & Dissertations

The growing popularity of Computational Fluid Dynamics (CFD) simulations among engineers necessitates the use of GPU acceleration for increased efficiency. NASA FUN3D offers GPU accelerated CFD simulations using unstructured grids across the speed regime from incompressible to hypersonic flows involving reentry. This work focuses on the generalized multi-color point implicit solver used in FUN3D, accounting for roughly half of the run time. Specifically, this work focuses on developing three optimized multi-color linear-solver kernels for the Intel Data Center Max 1550 GPU that is available on the Argonne Leadership Computing Facility’s (ALCF) exascale machine, Aurora. These optimized kernels work for a …

Language Barriers In Accessing Healthcare Services For Refugees In The United States, Sadaf Khuram

Communication & Theatre Arts Theses

Accessing healthcare is a pivotal aspect of refugees' integration into their host countries and significantly impacts their long-term health outcomes. The literature emphasizes the critical role of language proficiency in overcoming communication barriers within healthcare settings. This thesis, however, challenges the assumption that addressing language barriers alone is universally sufficient. It argues that the importance of language solutions is context-dependent, varying with the design of healthcare systems and the diverse needs and backgrounds of refugees. In some cases, focusing primarily on language barriers can divert resources from other critical areas, particularly when healthcare facilities have limited capacities or when services …

Draining Development: The Changing Nature Of Corruption In Post-Independence India, Chandra Tiwari

Graduate Program in International Studies Theses & Dissertations

The economic growth of emerging economies, particularly India’s, stands at a crossroads as the fight against corruption intensifies. Corruption poses a significant threat to the overall development of a country, necessitating the convergence of technological advances with national and global initiatives to combat the issue. Despite several ongoing efforts taken by international bodies to enforce regulations, challenges persist in curbing this issue due to the fundamental behavioral and structural factors at play. This dissertation investigates the dynamic evolution of corruption within a cash-based economy, a period of trade openness, and the contemporary digitalized age in India through a comparative case …

“We Are Trans, But We’Re Not Transitional”: Exploring Safety, Place, And Space In The Lives Of Transgender Individuals In Southeastern Virginia, Susana Avalos

Sociology & Criminal Justice Theses & Dissertations

In general, little research exists on trans people’s spatial experiences despite space being highly relevant to their experiences of violence and perceptions of safety. To date, two criminological studies have examined LGBTQ people’s fear of crime in relation to public or private places and spaces. This is in stark contrast to the sizable place and space literature on cisgender men and women. These topics from the perspectives of trans people are underexplored primarily because most criminological research has historically upheld binarized understandings of gender. Safety should not be privileged or limited to certain groups, individuals, or spaces. Instead, safety should …

Persistence And Completion Rates Of Community College Students: The Impact Of Receptivity To Social Engagement Scores Compared To Recorded Cocurricular Activity, Nancy Wagner Boylan

Educational Leadership & Workforce Development Theses & Dissertations

This study examined the relationship between Ruffalo Noel Levitz College Student Inventory Receptivity to Social Engagement scores and the persistence and completion of community college students. The Ruffalo Levitz College Student Inventory assesses student receptivity to institutional support services. Receptivity scores indicate a student's willingness to accept help in areas such as academic support and social engagement as well as career and financial guidance.

This research explored the impact of documented cocurricular involvement, measured through student activities indicators, on persistence and completion outcomes. Using ex post facto data and binary logistic regression analyses, the research focused on three populations at …

Effect Of Moderate Decrease In Contractility On Epithelial Cell-Cell Contacts Under External Stretch, Saika Sharmin

Mechanical & Aerospace Engineering Theses & Dissertations

Epithelial tissues are characterized by extensive cell–cell contacts and often subject to stretch during normal function. Cell-cell contact adhesion strength maintains mechanical continuity from cell to cell. Mechanical forces exerted by cells via actomyosin contractility are known to strengthen cell-cell adhesions to a certain extent. While it is known that a large decrease in contractility causes cell-cell contact rupture due to weakened adhesions, it is unclear how a moderate reduction in contractility affects cell-cell junction stability. Here, we studied how a moderate inhibition of non-muscle myosin II (NMII) affects the integrity of epithelial cell-cell contacts, especially when subject to the …

Flux Trapping Sensitivity On The Metallurgical State Of Superconducting Radio Frequency Niobium, Bashu Dev Khanal

Physics Theses & Dissertations

Trapped magnetic flux in superconducting radio-frequency (SRF) niobium cavities due to the incomplete Meissner effect is a significant source of rf losses. The relationship between flux expulsion and flux trapping sensitivity to the metallurgical state of 1.3 GHz and 3.0 GHz SRF niobium cavities fabricated from standard and cold-worked Nb sheets and subjected to various heat treatments has been studied. Flux expulsion increased with higher heat treatment temperature in all cavities. Nb cavities made from cold-worked sheets showed better flux expulsion after 800 ◦C/3 h compared to the standard SRF-grade Nb cavities. Similar flux expulsion was observed after annealing at …

Exploring The Relationship Between Cannabis Use Motives And Readiness To Change Among Young Adult College Students, Emma Kathryn Rawls

Psychology Theses & Dissertations

Cannabis use among young adult college students has risen steadily over the past decade, raising concerns about the associated health, academic, and psychological consequences. While cannabis use motives and readiness to change have each been linked to use patterns and outcomes, limited research has examined how these factors interact. The current study investigated whether readiness to change, based on the Transtheoretical Model (TTM), moderates the relationship between cannabis use motives and cannabis-related consequences as well as past-30-day use frequency. A sample of 100 college students 18-25 years old (M_age = 20.08, SD = 2.12; 67% female; 55.0% Black or …

Computational Investigation Of Energetic Materials: Influence Of Electronic And Steric Properties On Sensitivity And Decomposition Mechanisms, Elizabeth Ruth Zengel

Chemistry & Biochemistry Theses & Dissertations

Developing novel high energy density materials (HEDMs) requires knowledge of the causes and mechanisms of detonation. These chemical events are almost instantaneous and involve the release of a large amount of energy, which limits the experimental studies that can be performed on them. Computational methods including density functional theory (DFT) and molecular dynamics (MD) simulations have been used to investigate trigger bonds, those which break to initiate detonation. These bonds are commonly found within explosophores, substituents that increase the explosive potential of a molecule.

The Wiberg bond index (WBI) is an estimation of orbital overlap and bond strength between two …