Digital Commons Network^™

Investigation Into The Effectiveness Of G-C3n4 For The Degradation Of Indigo Dye In Aqueous Solution Via Electrocatalysis, Rolando R. Barron Jr

Theses and Dissertations

Indigo dye (IUPAC 2-(3-hydroxy-1H-indol-2-yl)indol-3-one) is one of the most used dyes in the textile industry worldwide with more than 40,000 tons produced each year. It can elicit adverse physiological responses in humans including vomiting, diarrhea, and other gastrointestinal conditions, and it is toxic in large amounts. There is also evidence to suggest that indigo is a teratogen and genotoxic in aquatic life. Environmentally, the enormous amount of indigo used in the textile industry has caused rivers and waterways to run blue as well as severely impacting aquatic and plant ecosystems. The chemicals used in its synthesis are also …

Cross-Frame Effects And Design Optimization For Skewed Steel I-Girder Bridges, Nisha Sthapit

Theses and Dissertations

Cross-frames are critical for load distribution and stability in steel I-girder bridges with complex geometry, especially during construction. However, they are often designed with standardized cross-sections that are uniform throughout the bridge. This thesis presents an optimization approach for cross-frame cross-sections for skewed steel I-girder bridges with integral and stub abutments with skews ranging from 15⁰-60⁰. This optimization, using Method of Moving Asymptotes (MMA), minimizes girder flange lateral bending stress while maintaining or reducing the total volume of the cross-frames from the original design. Validated 3D finite element models in CSI Bridge showed that the optimization achieved around 20% decrease …

The Factors That Affect Usm Student Experience In The General Chemistry Classroom, Emma Dickerson

Honors Theses

Chemistry has a reputation for being a challenging discipline for many students. Enrollment in chemistry courses is much lower than that of other disciplines due to “chemophobia”, which can be caused by many aspects of chemistry.^1-2To increase enrollment in chemistry, it is important to understand how to improve the student experience in the classroom. To determine the factors that affect a student’s experience in their current chemistry class, the Chemistry Attitudes and Experiences Questionnaire (CAEQ) was adapted and given to students in General Chemistry I and II classes at The University of Southern Mississippi. Descriptive statistics, an Analysis …

Wind-Induced Gravel Blow-Off: Experimental Investigations And Predictive Modeling For Resilient Roof Design, Md Safwan Ahsanullah

All Dissertations

Roof gravel blow-off during severe windstorms is a major hazard, leading to roof damage and significant downwind impacts. Understanding the initiation mechanisms for gravel blow-off is critical for improving building design and mitigating windborne debris risks. Existing experimental data on the wind speed required to initiate gravel blow-off have been collected from high-speed, full-scale tests at wind tunnels. While these tests form the basis of current design guidelines, they are expensive and can lack generalizability. As a result, rooftop gravel is frequently blown off at wind speeds below the design thresholds. This dissertation investigates the onset of rooftop gravel motion, …

User Acceptance Of Shared Autonomous Vehicles, Haotian Su

All Dissertations

A dissertation is proposed to explore user acceptance of shared autonomous vehicles (SAVs). SAVs are facing limited user acceptance. To systematically tackle the user acceptance barriers of SAVs, the main problem can be disintegrated into two sub-problems of user acceptance of autonomous vehicles (AVs) and ridesharing. The comfort of the ride experience in AVs is a determinant of user acceptance. Understanding the influential factors and developing methodologies to quantify human comfort in AVs are essential to facilitating future research to improve human comfort in AVs. The current pooled rideshare (PR) service closely resembles the anticipated future of SAVs. Understanding why …

Understanding The Role Of Ligamentous Constraint In Trapeziometacarpal Pathomechanics, Lizzie Walker

All Dissertations

The trapeziometacarpal (TMC) joint is the most common site for osteoarthritis (OA) in the upper limb. This joint is characterized by its wide range of motion and limited bony stability, making it susceptible to OA. The TMC joint relies mostly on ligaments and muscles for its static and dynamic stability, respectively. While importance of both volar and dorsal capsular TMC stabilizers has been demonstrated, the role of TMC ligamentous tissues in the development of thumb basal joint OA remains unclear.

The goal of this work was to identify morphometric and mechanical changes in key TMC ligament stabilizers, including the volar …

The Effects Of Cigarette Smoke Extract On Osteoarthritis In A Primary Joint Tissue Explant Model, Emily Sawvell

All Dissertations

Osteoarthritis (OA) is the most common degenerative joint disease in the world with an economic burden of nearly $140 billion annually. Factors identified to increase the risk of developing OA include age, obesity, sex, race, genetics, and previous joint injury. However, one risk factor that has been scarcely studied in OA etiology is cigarette smoking. While some studies have reported smoking to protect against OA, increasing evidence suggests that cigarette smoking results in more severe and painful OA, increases the rate of developing OA, and reduces the efficacy of pain medications and arthritis-targeting therapies. Despite this, the impact of cigarette …

Grid Forming Inverters For Microgrid Operation Enhancement, Jan Westman

All Dissertations

Modern electric power systems are confronted with several major challenges including the increasing frequency and severity of weather events, aging infrastructure, high material costs, cyber-attacks, and substantial delays in global supply chains. Microgrids provide a solution to these challenges by insulating customers from the power outages occurring in their local distribution system. A microgrid is a small independent power system with its own power generation and energy storage resources that can supply customers’ electricity needs. When an outage occurs, a circuit breaker will disconnect the microgrid from the distribution system. Successful operation of the microgrid requires one or more devices …

Integrating Applied History And Artificial Intelligence (Ai) Into City Planning Practice, Russell H. Stall

All Dissertations

History matters. History provides a vital foundation for shaping present decisions and future planning. By understanding a city’s past, cities can make more thoughtful, informed choices to guide development and policy with greater intention and impact.

Greenville, South Carolina, is a unique city planning case study and learning laboratory. Greenville’s Downtown revitalization since the 1980s demonstrates how historical insights can be integrated into contemporary policymaking to create vibrant, human-centered, and citizen-focused urban environments. Greenville’s evolution from a deserted, forgotten Main Street to one of the world’s most livable cities is an example of community development worthy of emulation from other …

Exploring The Pedagogical Impact Of Software Development Live Streams: Informal Learning Opportunities For Software And Game Developers, Ella Kokinda

All Dissertations

Live streaming is an increasingly popular medium for throwing back the curtain on software development where streamers and viewers share their knowledge and experiences. Popular platforms like Twitch and YouTube enable developers to stream live coding sessions where people around the world can engage in real-time collaboration, feedback, knowledge sharing, and skill development. This work investigates the pedagogical implications and learning opportunities present in software and game development live streaming while focusing on the role of streaming as a learning environment and collaborative community. We begin by exploring summer camps as an informal learning opportunity for STEM education, highlighting the …

Countering Deficit Narratives Through A Blackcrit Lens By Examining Case Studies Of Black College Mathematics Students’ Classroom Experiences, Akhenaton Wilbourn

All Dissertations

This dissertation examines the lived experiences of 11 Black college mathematics students at their predominantly white institution (PWI) through the lens of Black Critical Theory (BlackCrit) to counter deficit narratives about the racial achievement gap (RAG) in mathematics education courses. Deficit narratives often attribute disparities between Black and white students’ mathematical performance to assumed deficiencies in Black students’ abilities rather than systemic inequities, historical marginalization, and ongoing anti-Blackness in educational settings (Cobb & Russell, 2015; Kress, 2021). Using multiple case studies, this study explores how anti-Blackness manifests in mathematics classrooms, how students navigate tensions between multiculturalism, neoliberal educational policies, and …

Deciphering And Translating Bioinspired Structures For Engineering Materials Design Via Computational Modeling And Machine Learning, Zhangke Yang

All Dissertations

Nature has evolved extraordinary structural materials—such as nacre, bone, and the mantis shrimp’s dactyl club—that achieve remarkable combinations of strength, toughness, and impact resistance. These properties arise from sophisticated synergies between structure and composition. Inspired by these biological systems, this dissertation presents a comprehensive investigation into bioinspired materials, uncovering fundamental mechanisms and providing guidance on designing materials with superior mechanical properties.

This dissertation begins by examining the "brick-and-mortar" structure of nacre, which informs the design of layered polymer-graphene nanocomposite films. Using coarse-grained molecular dynamics simulations, I elucidate mechanisms of dynamic wave propagation and energy dissipation in these systems, providing critical …

Real-Time Active Thermal Management And Degradation Forecasting Of Power Electronics Building Blocks In All-Electric Ships, Ali Moghassemi

All Dissertations

With advancements in semiconductor technology, power electronic devices play a critical role in modern power systems, enabling efficient energy conversion in applications such as renewable energy integration, electric vehicle drives, industrial automation, and Navy ship power systems. However, the increasing use of power converters presents challenges such as harmonic reduction, cost optimization, reliability improvement, and thermal management, especially in weight- and space-constrained environments like wind turbines and shipboard systems. High-frequency switching, while reducing passive filter size, increases thermal stress on semiconductor devices, impacting efficiency and longevity. Active thermal control, which regulates junction temperature through power loss management, and degradation forecasting, …

Live-Streaming E-Commerce: The Role Of Firms And Influencers In Driving Sales, Jingyun Hu

All Dissertations

Livestreaming is a transformative technology that removes the limitations of time and lo- cation, enabling real-time interaction between hosts and audiences. When combined with online shopping, it creates livestreaming e-commerce, a fast-growing marketing channel where influencers promote products live and engage directly with consumers.

My doctoral dissertation explores how firms and influencers collaborate effectively in this emerging retail space. Livestreaming e-commerce offers new opportunities for reaching consumers, but also raises questions about how to manage partnerships and present products in a dynamic, real-time setting. Specifically, I investigate how firms should choose and switch influencers over time, and how influencers can …

Understanding Dimensional Stability Of Polymer Surgical Mesh, Simeon J. Mckelvey

All Dissertations

Polymer surgical mesh is a biomedical implant that has revolutionized the repair of the abdominal wall and pelvic floor. Each year, over 1.6 million Americans undergo surgical procedures using polymer surgical mesh to treat conditions where internal organs protrude through weakened tissues. This material is used in approximately 90% of hernia repairs, 80% of stress urinary incontinence procedures, and 30% of pelvic organ prolapse surgeries.

Despite this widespread use of polymer surgical mesh, post-implantation complications have prompted regulatory investigation and scrutiny. These complications stem from the mesh's behavior within the human body, including wrinkling, contraction, and loss of fixation, which …

Am I Woke Enough To Serve In Healthcare: A Secondary Analysis Of Pre-Health Students’ Personal And Professional Growth By Engaging In Cultural Competency Assessments, Harolynn Williams

All Dissertations

Healthcare providers must be equipped to serve an increasingly diverse population, yet cultural competence remains underemphasized in undergraduate pre-health education. This study explored how embedded cultural competency training influences undergraduate pre-health students’ perceptions of personal and professional growth. Using a qualitative descriptive design, the research incorporated intercultural assessments, the Intercultural Development Inventory (IDI), and the Global Competence Certificate (GCC), along with qualitative reflections from students enrolled in three versions of a cultural competence course: a year-long course, a semester-long course, and a short-term study abroad immersion six-week course. Findings revealed that students demonstrated measurable growth in cultural awareness, knowledge, communication, …

An Analysis Of Principal Influence On Teacher Retention In A Rural School District: An Exploratory Qualitative Study, Stephanie Davis

All Dissertations

Research shows that nearly one-third of novice teachers leave the profession before their third year, and almost half leave by their fifth year, with turnover rates remaining steady. Teacher job satisfaction and dissatisfaction are influenced by various factors, with administrative support playing a key role. This exploratory qualitative study examined how principals' leadership behaviors affect teacher retention. Through surveys and interviews with principals and teacher representatives from nine schools, the study found that positive principal leadership significantly influences teachers' decisions to stay in their schools. Principals actively engage in behaviors, both direct and indirect, that help retain teachers. The study …

Ceramic Membrane Evaluation Via Automated Filtration Systems For Water Treatment And Resource Recovery, Weiming Qi

All Dissertations

Membranes are an advanced and mature water and wastewater treatment technology. Membrane fouling is a key difficulty for all membrane filtration processes, leading to significant attention in the literature over the years. A common problem in laboratory-scale membrane research is that the testing methods in the laboratory are often quite different than industrial applications due to the limitations of manual experimental setups. An automated membrane filtration apparatus was built in the lab to solve this problem by allowing long-term filtration, frequent backwash and CIP, and high-accuracy operation. The filtration system achieves different cleaning strategies for both theoretical research and practical …

The Effect Of Nuclear Isomers On S-Process Nucleosynthesis, Jaad Tannous

All Dissertations

s-Process nucleosynthesis is a process in which stars produce elements of mass range A = 57 to 210. Since the days of B2FH, immense work has gone into quantifying and computing s-process yields and pathways. We expand upon said work along two fronts. The first front sets up the framework for proper treatment of nuclear isomers in network calculations. We apply the framework to study 85Kr, which is a pivotal isotope in the s-process chain that affects the abundance yields of Strontium and Rubidium isotopes. In particular, we are interested in the ratio of 88Sr/86Sr and 87Rb which are important …

Synthesis Of Nanoparticles In Silicate Matrix And Stimuli Responsive Nanocomposite Polymer Films, Dimuthu Edirisinghe

All Dissertations

Interactions between aqueous metal ions and soluble silicates lead to the formation of insoluble metal silicate complexes that form nanoparticles via condensation polymerization. Metal silicates function as nanoreactors, effectively condensing metal ions into nano-sized particles that can undergo further chemical transformations. Core-shell nanostructures present an intriguing strategy for integrating materials with different properties. The silicate shell around the silver nanoparticles can be successfully infused with other metal ions, enabling subsequent reactions to tailor their properties. Silver nanoparticles exhibit strong interactions with light, surpassing other chromophores, including noble metal nanoparticles, due to their highly efficient surface plasmonic resonance. The unique optical …

Identification And Characterization Of Intermediate Phenotypes To Decipher Genetic Architecture Of Stalk Lodging Resistance In Maize (Zea Mays L.), Bharath Kunduru

All Dissertations

Maize is a key contributor to global food security and incurs severe yield losses due to stalk lodging, the permanent displacement of plants from an upright growth habit due to mechanical damage to the stem (stalk). Stalk lodging resistance, an indicator of the stalk ability to resist lodging, is a complex trait and determined by several structural, geometric, and material properties of stalks, collectively referred to as intermediate phenotypes, whose identity and genetic framework are poorly understood. Therefore, progress in resolving the genetic architecture of stalk lodging resistance was impeded by a lack of standardized phenotyping methodologies and a poor …

Decomposition And Coordination For Multiobjective Optimization: A Framework And Methodology, Philip J. De Castro

All Dissertations

In this work, we consider finding Pareto efficient solutions for complex multiobjective optimization problems (MOPs). Complex MOPs are unique in the literature because they have many more objective functions than is typically considered. In fact, such complex MOPs will have 30+ objective functions. This large problem size presents computational and coginitive difficulties. Computationally, standard techniques for solving MOPs are often ineffective and cognitively it is difficult for a decision maker (DM) to handle all of the information provided in such a large problem. To address these challenges, we develop a decomposition and coordination framework. This framework will allow us to …

Strengthening The Bonds Between Us: An Empirical Investigation Of Morale In Human-Ai Teams And The Socially Supportive Ai Teammates Who Empower It, Rohit Mallick

All Dissertations

This dissertation investigates how artificial intelligence (AI) can be designed to improve the collective emotion within a team. A team's collective emotion, or morale, describes how motivated, optimistic, and enthusiastic the group is in accomplishing its goals. We conducted four studies that compared different social support strategies that AI teammates can provide to the team. Study 1A found that AI teammates who communicate with emotions can better motivate human team members and promote awareness of team dynamics and environmental changes. Study 1B found that human teammates become more motivated and happier when their AI teammates express joy and are close …

Integrating Artificial Intelligence For Transportation Cyber-Physical Systems: From Detection To Cyber Resilience, Reek Majumder

All Dissertations

This dissertation investigates different methods for methane detection using unmanned aerial vehicles (UAVs). The author addresses the fundamental problem of methane emissions, a potent greenhouse gas responsible for global warming. The first part of the dissertation aims to create a cost-effective system for real-time methane detection and intensity prediction using ensemble learning models trained on meteorological parameters. The ensemble learning-based classification models show a high accuracy for methane detection.

The second part of the dissertation investigates cyberattack detection for UAVs using a graph-based intrusion detection system (IDS) for controller area networks (CAN). This lightweight, protocol-independent IDS uses graph-based machine learning …

Amyloid Aggregation And Mitigation, Zhenzhen Zhang

All Dissertations

The buildup of protein in tissues and organs plays a major role in unfunctional several serious diseases, including Alzheimer’s disease, Parkinson’s disease, and Type 2 diabetes, each tied to specific proteins that form harmful amyloid deposits. Amyloid aggregation typically follows a sigmoidal kinetic curve, beginning with a slow lag phase, followed by rapid fibril growth, and eventually reaching a plateau where mature, stable fibrils are formed. However, the early stage of aggregation remains particularly difficult to capture experimentally due to the highly dynamic nature and low abundance of small oligomeric species. In this dissertation, we employed discrete molecular dynamics (DMD) …

An Investigation Of Design Processes And Their Effects On Accessibility In Narrative Themed Environments, Arielle Spencer

All Dissertations

Accessibility matters, and not merely in meeting minimum codes or limited to basic necessities. Access and inclusion matter still more in places of recreation and leisure which have too often been overlooked or considered low priority, however it is precisely these places that merit special attention. Narrative Themed Environments occupy a unique position relative to the general built environment, often acting as utopic ‘other-spaces’ for enjoyment, freedom, and escape. However, for guests with disabilities, current themed experiences can often lack true inclusivity and instead create inequality, segregation, diminished experiences, and feelings of isolation and exclusion. The peculiar idiosyncratic design process …

User Acceptance Of Shared Autonomous Vehicles, Haotian Su

All Dissertations

A dissertation is proposed to explore user acceptance of shared autonomous vehicles (SAVs). SAVs are facing limited user acceptance. To systematically tackle the user acceptance barriers of SAVs, the main problem can be disintegrated into two sub-problems of user acceptance of autonomous vehicles (AVs) and ridesharing. The comfort of the ride experience in AVs is a determinant of user acceptance. Understanding the influential factors and developing methodologies to quantify human comfort in AVs are essential to facilitating future research to improve human comfort in AVs. The current pooled rideshare (PR) service closely resembles the anticipated future of SAVs. Understanding why …

Identification Of Mitochondrial Defects And Metabolic Consequences In Lynch Syndrome-Related Endometrial Cancer, Mikayla Bowen

Dissertations and Theses (Open Access)

Lynch syndrome (LS), defined by mutations in DNA mismatch repair genes including MSH2, carries a 60% lifetime risk of developing endometrial cancer (EC). Mismatch repair deficiency (MMRd) causes hypermutability, which is assumed to be the main driver of LS-related EC development. However, incomplete penetrance of EC development in women with LS suggests that other modulators are at play. The broad hypothesis of this dissertation is that MMRd causes consequences beyond hypermutability to impact LS-related EC development. Recent studies utilizing our lab’s Msh2-deficient mouse model for LS-EC revealed mitochondrial dysfunction in EC pathogenesis. This new insight led to the …

Immune Landscape Of Early Liver Metastatic Lesions In A Novel Immunocompetent Murine Colorectal Cancer Metastasis Model, Alaa Mohamed

Dissertations and Theses (Open Access)

Colorectal cancer minimal residual disease (MRD) represents a major clinical problem for colorectal cancer patients, with failure rates of surgery and adjuvant chemotherapy between 5% to 40% depending on stage of disease. In our study, we simulated MRD using genetically engineered organoids with precise somatic editing of APC and TP53, creating a murine model that mimics human liver metastatic colorectal cancer. By implementing a meticulously timed experimental metastatic model, we could detect microscopic tumor lesions. Through genomic and transcriptomic analyses, we pinpointed the importance of macrophages, particularly those expressing high levels of CSF1R, in these microscopic metastatic focal lesions. We …

Unraveling Epigenetic Mechanisms That Regulate Breast Cancer Lung Metastatic Relapse By Rewiring The Immune Microenvironment, Jayanta Mondal

Dissertations and Theses (Open Access)

Metastasis accounts for >90% of cancer-related deaths and thwarting metastasis is widely considered to be the “Holy Grail” of cancer treatment. Breast cancer is the most common cause of cancer-related death among women and is characterized by its proclivity to spread to distant secondary organs like the lungs, and the brain. These disseminated tumor cells lie dormant at the secondary site and can undergo metastatic relapse. Epigenetic alterations are a predominant hallmark of cancer, however, its role in facilitating reawakening of dormant cancer cells and the subsequent metastatic relapse remains to be elucidated. To address this gap of knowledge, we …