Digital Commons Network^™

Semi-Supervised Learning For Annotation And Representation Of Single-Cell Rna Sequencing And Spatial Transcriptomics Data, Haoran Liu

Dissertations

Semi-supervised learning has emerged as a powerful paradigm for analyzing single-cell RNA sequencing (scRNA-seq) and spatial transcriptomics (ST) data, where full annotation is often costly or impractical. scRNA-seq technologies measure the expression of thousands of genes across tens of thousands of cells, whereas ST additionally captures the spatial coordinates of gene expression within intact tissue sections. Annotation is a key step in both scRNA-seq and ST analysis pipelines, aiming to identify cell types, spatial domains, and latent biological structures. However, most existing annotation approaches rely on separate clustering methods that are typically fully unsupervised and fail to leverage side information …

Beyond Words: A Systematic Multimodal Framework For Text, Images, And Extreme Helpfulness In Online Reviews, Alvaro J. Aguado Marin

Dissertations

Online product reviews have become increasingly multimodal, combining text with media-rich elements such as images. However, academic research has largely examined textual features in isolation, overlooking how visual content and its interaction with text shape perceived helpfulness. This dissertation addresses that gap by developing and empirically validating a comprehensive framework capturing how textual, visual, and contextual features collectively influence review evaluation. Grounded in the Elaboration Likelihood Model (ELM) and extended through the Text-Image Elaboration Likelihood Model (TI-ELM), the framework advances understanding of how consumers process content from both user- and business-generated sources. It also lays the foundation for examining emerging …

Computational Design Of Nanoporous Materials For The Adsorption Of Per- And Polyfluoroalkyl Substances, Daniel D. Mottern

Dissertations

Per- and polyfluoroalkyl substances (PFAS) are a large family of chemicals that have seen wide usage due to their fluorinated carbon backbone. The presence of strong C-F bonds in the backbone lends PFAS molecules high thermal and chemical stability, as well as strong hydrophobicity and lipophobicity. This combination of properties has led to heavy use of PFAS as surfactants, non-stick coatings, and aqueous foam forming films and flame retardants. However, these properties bring their own consequences. The high chemical and thermal stability of PFAS renders them persistent, with the C-F bonds resisting naturally occurring forms of degradation. Existing forms of …

Entropic Forces Near Fluctuating Surfaces, Rubayet Hassan

Dissertations

Nanoscale structures are inherently dynamic due to persistent thermal fluctuations. Even in solid materials, these random deformations, driven by ambient thermal energy, can become significant when their characteristic scale approaches that of the structure itself and strongly influence their overall mechanical behavior. Examples of such structures include crystalline membranes, appearing in diverse forms such as nanotubes, nanoribbons, and kirigami/origami structures. Similarly, biological nanostructures, including lipid membranes, microtubules, actin filaments, and DNA, exhibit extreme flexibility and responsiveness due to their low bending rigidity. Numerous physiological processes are intrinsically linked to these thermal fluctuations, including exocytosis and endocytosis, membrane fusion, pore formation, …

Computational Methods For Single-Cell And Multi-Omic Data Integration And Regulatory Network Inference, Jianlan Ren

Dissertations

Single-cell and multi-omic technologies have transformed the dissection of cellular heterogeneity and regulatory dynamics in health and disease. However, the high dimensionality, technical variability, and biological complexity of these datasets present significant challenges for integration, annotation, and interpretation. In this dissertation, a suite of computational approaches is introduced to address key problems in single-cell and multi-omic data analysis through model-based innovations and applied statistical frameworks.

First, a constrained deep learning framework for single-cell data integration, label transfer, and clustering is proposed. By incorporating biologically motivated constraints into the training process, robust performance is achieved across simulated and benchmark datasets spanning …

Material Degradation And Analysis Of N-Doped Graphene/Mof Nanocatalysts For Orr In Electrochemical Energy Systems, Niladri Talukder

Dissertations

The development of advanced electrochemical energy conversion and storage systems is crucial for achieving sustainable energy security. As alternatives to precious metal-based catalysts in electrochemical systems, especially for the oxygen reduction reaction (ORR), Nitrogen-doped Graphene with Metal-organic Frameworks (N-G/MOF) nanocatalysts have shown exceptional promise in recent years. This research advances the understanding of N-G/MOF nanocatalysts by systematically examining their structural features, degradation traits, correlated performance losses, and other aspects related to catalytic activities.

First, nitrogen-doped graphene (N-G) nanocatalysts were thoroughly investigated, resolving their physical properties, the influence of synthesis parameters, molecular-level material structures, and chemical and electronic structural details of …

Data-Driven Analysis And Atomistic Simulations Of Next-Generation Materials For Energy Conversion And Storage, Yuliang Shi

Dissertations

Metal-organic frameworks (MOFs), with their modular architectures and tunable properties, represent an especially rich domain for accelerated material design and discovery for a range of diverse applications. Within this class of multifunctional materials, two-dimensional (2D) electrically conductive MOFs (EC MOFs) are of particular interest, as their 7r-stacked layered structures combine permanent porosity with electronic conductivity, enabling potential breakthroughs in energy storage, energy conversion, and quantum sensing. But the discovery and design of new EC MOFs based on expensive experimental screening is increasingly impractical due to the infinite chemical space. Furthermore, the practical implementation of EC MOFs for specific tasks depends …

Level Up Your Teaching: A Qualitative Analysis Of Teachers’ Perceptions On Gamification As A Tool For Learning, Bryant Wesley Lazenby

Dissertations

This qualitative study investigated K-12 teachers’ views about gamification as an instructional tool to increase student motivation, self-efficacy, and learning mastery. Kelly’s Curriculum Theory and Bandura’s Self-Efficacy Theory were used to investigate how gamified learning environments affect teacher practice and self-efficacy. Seventeen teachers participated in a researcher-designed Qualtrics survey that included both Likert-style and open-ended items. The researcher used descriptive statistics and thematic coding of responses, based on participants’ self-identified levels of gamification experience. The research produced three main findings, which showed that (1) Gamification motivates students through collaborative work, challenging tasks, and progress tracking systems, (2) Students build self-efficacy …

Student Voices On Trauma And Resilience: A Critical Phenomenological Study Of Gun Violence And College Student Experiences, Lucia Helena Garcia

Dissertations

This study posits that gun violence in the United States is a public health crisis and that colleges and universities must actively collaborate to develop and implement solutions to address and prevent this crisis, which affects communities and students. Gun violence can and does lead to disruptions in educational access, travel and safety, as well as have longstanding impacts on mental health. While extensive research exists that is focused on the impact of community and gun violence exposure on K-12 students, the impact of community violence and gun violence exposure on emerging adults in university settings is limited and remains …

Understanding Medication Adherence Among American Indian/Alaska Native People With Type 2 Diabetes Within A Commercial Health System, Leandra Bitterfeld

Dissertations

American Indian/Alaska Native (AI/AN) adults experience higher rates of type 2 diabetes and worse glycemic control than non-Hispanic White Americans. Despite the importance of medication adherence for T2DM management, there is only one study in the last 15 years examining the relationship between medication adherence and A1C among AI/ANs. Furthermore, T2DM research among AI/ANs has largely been conducted within Indian Health Service and Tribal healthcare systems, though most AI/ANs live outside of reservations, meaning many use commercial health systems. The purpose of this dissertation is twofold. We sought to first understand the experience of AI/AN people accessing T2DM in a …

Polycystin-2 Is Cardioprotective Against Myocardial Infarction By Regulating The Calcium-Mediated Er-Stress Response, Virdjinija Vuchkovska

Dissertations

Patients with autosomal polycystic kidney disease (ADPKD) have an increased risk and worse outcomes after acute myocardial infarction, but the mechanism for this is unknown. Polycystin 2 (PC2), one of the two main proteins mutated in ADPKD, is a calcium permeant channel that localizes to the ER/SR. In non-cardiac cells, PC2 regulates the unfolded protein response (UPR) pathway under ER stress. However, whether PC2 is cardioprotective against ER stress is unknown. We found that PC2 expression increased in cardiomyocytes from human ischemic hearts and infarcted murine hearts. Cardiomyocyte-specific PC2 KO (PC2 KO) mice had worsened cardiac function after myocardial infarction …

Using Light To Dissect Mechanisms Of Septin Recruitment, Shreya Chandrasekar

Dissertations

Cells interpret biochemical and mechanical signals through dynamic regulation of the cytoskeleton and adhesion complexes, enabling key processes such as shape adaptation, force generation and migration. As these signals vary in both time and space, they can be challenging to resolve using traditional bulk assays. To overcome this limitation, we employ light-based optogenetic tools to reversibly modulate biochemical signals and mechanical equilibrium within cells. Specifically, we use the iLID optogenetic approach to locally activate signaling and manipulate contractility within the cytoskeleton for the purpose of investigating the role of RhoA and contractility on septin organization and adhesion protein localization. We …

Effects Of Commission Errors During Prompting On Skill Acquisition And Maintenance, Molly K. Mutchler

Dissertations

Procedural fidelity refers to the extent to which procedures are implemented as intended. Engaging in procedural fidelity errors can lead to detrimental outcomes during skill acquisition and maintenance. The purpose of this study was to parametrically evaluate and compare two commission errors during prompting procedures using an arbitrary tacting task taught to college-aged students. Participants learned to tact four sets of arbitrary pictures and names. Prompting errors consisted of either providing the correct letters for a name in an incorrect order (i.e., an error within a component of the name) or providing the correct name for another picture (i.e., an …

Environmental Beliefs Among Evangelical Leadership, Jeffrey Stark

Dissertations

There has been consensus among climate scientists for over a decade about the reality of human caused climate change. Even with this consensus, the public understanding of this issue remains divided based on factors generally unrelated to the science. Evangelical Protestants are one group which consistently polls as more skeptical of climate change. This is true not only when compared to the general population but also when compared to other religious demographics. Most large-scale surveys of evangelicals assume the demographic to be a monolith and do not attempt to break the demographic down further. In this mixed methods study, we …

Additive Manufacturing Of Carbons From Commodity Polyolefins, Paul Smith

Dissertations

Though tremendous progress has been made engineering carbon materials across length-scales from the molecular to the macroscopic, on-demand macro-structural control of carbons is still developing. Many carbon materials like graphene, carbon nanotubes, activated carbons, and carbon fibers have powder or fiber form factors. Recent research has pioneered on-demand carbon production through additive manufacturing (AM) via 1) extrusion and post-processing of highly filled carbon slurries, or 2) printing and pyrolysis of polymeric carbon precursors such as polyimides, acrylated polyethylene glycol, and phenolics. While groundbreaking, most methods face challenges with adoption due to costly/complex materials and manufacturing processes, and large dimensional changes …

A Mixed-Methods Design-Based Research: Study Of Teacher Self-Efficacy And The Implementation Of Social Emotional Learning In The High School Classroom, Avia Brown

Dissertations

The escalating mental health crisis among adolescents, exacerbated by the COVID-19 pandemic, positioned schools as critical intervention sites for supporting student well-being (K. McNamara, 2020). However, teacher capacity and self-efficacy in implementing social-emotional learning (SEL) competencies remain significant barriers to effective, sustainable practice. This mixed-methods design-based research study examined the efficacy of professional development and instructional coaching in enhancing teacher self-efficacy and supporting the implementation of SEL competencies in high school classrooms.

The researcher employed a comprehensive, five-stage design thinking framework (empathize, define, ideate, prototype, test) to develop and evaluate a structured eight-week professional development and coaching intervention targeting SEL …

Educators’ Perspectives, Practices, And Implications Of Ai In Education For A Title I Middle School, Melanie N. Garland

Dissertations

This study examines educators’ perspectives, instructional practices, and the perceived implications of artificial intelligence (AI) integration within a Title I school context. As AI technologies become more embedded in educational settings, it is essential to understand how teachers in under resourced environments engage with these tools. The research explores how educators perceive the benefits and challenges of AI, the extent of its integration into their pedagogy, and the broader implications for access, particularly for subgroups such as students with disabilities (SWD) and English language learners (ELLs), as well as student engagement and instructional effectiveness. A qualitative case study methodology was …

Elucidating Differences In Constitutionally Isomeric Diamine- And Bisphenol-Based Polybenzoxazine Networks, Benjamin L. G. Morasch

Dissertations

This dissertation aims to expand the fundamental understanding of diamine-based benzoxazine chemistry by examining how synthesis influences the network properties of 4,4’-ddm and phenol-based (P-ddm) benzoxazine, compared to the constitutionally isomeric bisphenol-F and aniline-based (BF-a) benzoxazine. While bisphenol-based benzoxazines such as BF-a have been studied more extensively, diamine-based benzoxazines are still relatively unexplored due to the competition with the formation of 1,3,5-hexahydrotriazine intermediates and the inconsistent thermal and mechanical properties reported in the literature. These inconsistencies stem from factors including synthetic methods, curing conditions, and degradation during polymerization that have been overlooked.

To address these issues, this dissertation is organized …

General Education Teachers' Perspectives And Practices For Supporting English Language Learners In Memphis Charter Schools, Ijiah Hargrove

Dissertations

The growing enrollment of English Language Learners (ELLs) in U.S. schools, particularly within urban charter settings, presents unique challenges for general education teachers who are often underprepared to meet both linguistic and academic needs. The purpose of this study was to explore the instructional strategies, perspectives of their ability of self-efficacy, and institutional factors that shape how K–8 charter school teachers in Memphis support ELLs. This work is significant because teachers’ beliefs, preparation, and available resources directly impact ELL achievement and equity in education.

A qualitative single-case study design was employed, with twelve general education teachers recruited through purposeful sampling. …

Upcycling Commodity Polymers To Advanced Materials For Energy And Environmental Sustainability, Anthony Griffin-Espinoza

Dissertations

Synthetic polymers play an essential role in nearly every aspect of our lives. Extending beyond single-use packaging, polymeric material design has progressed to attain tailorable architectures granting exceptional performance across advanced applications, including carbon-fiber reinforced polymer composites for aerospace, conductive materials for soft electronics, and drug carriers for biomedicine. While highly promising, intricately designed polymers needed to achieve excellent performance often have limited processability, complex synthetic methods, and expensive precursors. Furthermore, due to a lack of recyclability, commodity polymer waste streams result in both environmental impacts and a substantial loss of economic value. This dissertation focuses on developing robust strategies …

Privacy Preserving-Based Artificial Intelligence For Precision Agriculture, Partha P. Sengupta

Dissertations

The research work finds a solution to precision agriculture of cotton cultivation using artificial intelligence (AI) models. Two sets of model performance based on the application are selected namely a low resource and a high resource setting. This is because using drone surveys to capture images identifying the classes of stressed and unstressed cotton plantation requires limited model architecture and CPU based computation. Thus, traditional AI models were selected for low resource settings. Again, for high computation intensive models like transfer learning-convolution neural network (CNN) based architectures were grouped into high resource settings. There was another issue of class imbalance …

The Malonate Template: The Key To Unlocking Novel Amino Acids, Thomas Owens

Dissertations

The “Malonate Template” provides access to various amino acids, all from a common intermediate. Herein, demonstrates the use of the malonate template to establish a synthetic route to both 2-thiohistidine and 2-thio-3-N-methyl-histidine from a benzyl methyl malonate derived intermediate. Furthermore, efforts exploiting the applicability of the malonate template for the of both 2-thiohistidine and 2-thio-3-N-methyl-histidine as a suitable alternative to methods previously described by Erdelmeier are described.

The method presented incorporates modifications to the biomimetic pathway described by Erdelmeier for the synthesis of 2-thiohisidine. By exploiting the biomimetic formation of 2-thiohisitidne’s mechanism via mass spectrometry, we …

Understanding Crystallization Behaviors Of Polyethylene-Derived Vitrimers, Sara Valdez

Dissertations

Polyolefins (POs), particularly polyethylene (PE) and polypropylene (PP), are among the most widely utilized polymers globally, valued for their low production costs and favorable mechanical properties stemming from their semicrystalline microstructure. However, their extensive use and improper disposal have raised serious environmental and human health concerns. In response, PO-derived covalent adaptable networks (CANs) have emerged, integrating dynamic chemistries to enable recyclability and sustainable end-of-life strategies. While existing literature has largely focused on novel CAN systems, structure–property relationships, and network rearrangement in relation to thermal transitions (e.g., topological freezing temperature), the influence of network formation on crystallinity and crystallization kinetics remains …

An Exploration Of Enablers, Barriers, And Strategies Influencing Black College Alumni's Sense Of Belonging Through The Lens Of Cultural Competence, Marc' C. Bady

Dissertations

According to Pew research, 53% of Black students in the United States are enrolled in predominantly White institutions, or PWIs (Hatfield & Anderson, 2024). Black alumni who attend PWIs are one among many marginalized and underrepresented vulnerable populations (Tucker, 2021). The purpose of this study was to engage with Black alumni who attended and graduated from PWIs to learn about their experiences with academic enablers, barriers, and strategies for success as a PWI student. The researcher interviewed six alumni who graduated from a Southeastern research one institution to explore their lived experiences at a PWI. The researcher chose to use …

Motivators And Work Role Satisfaction Among A Post-Pandemic Multi-Generational Sports And Entertainment Industry Workforce, Christopher J. Kinnan

Dissertations

This quantitative causal-comparative study explored intrinsic and extrinsic motivators and work-role satisfaction among a post-pandemic, multigenerational workforce in the North American sports and entertainment industry. Using an adapted version of the Sports Grounds Safety Authority’s (SGSA, 2022) Evaluation of Systematic Stewarding Challenges instrument, the study analyzed data from 560 participants representing safety, security, and service roles across sports and entertainment venues. The research examined generational differences in motivation, satisfaction, and barriers to retention within the framework of Human Capital Theory, Herzberg’s Two-Factor Theory, and Self-Determination Theory.

Principal component and confirmatory factor analyses verified the reliability and validity of the adapted …

An Examination Of African American Male College Students’ Perceptions Of Academic Engagement, Social Capital, And Success As Members Of Black Greek Letter Organizations On Predominantly White Campuses, Jerid P. Woods

Dissertations

This exploratory qualitative study examines the experiences of Black male students at predominantly White institutions (PWIs) through the lens of Yosso's Cultural Capital framework. It explores how membership in Historically Black Greek Letter Organizations (HBGLOs) shapes academic engagement, development of cultural and social capital, and academic success by leveraging cultural wealth.

Data were collected through semi-structured interviews with ten participants from various HBGLOs, and thematic analysis was used to identify key themes and patterns. Findings highlight that HBGLOs act as vital sources of social, cultural, and academic support, fostering a sense of belonging, promoting academic achievement, and creating leadership opportunities. …

Do They Matter? What Role Do 5th-12th Grade Teachers' Attitudes Have In The Academic Success Of Black Girls In Classrooms?, Kamita R. Thigpen

Dissertations

There is a recognized need to focus on the intersectionality of race and gender to determine the specific needs of Black girls in education and for them to gain more academic success. This study set out to determine teachers' attitudes towards Black girls in the post-racial era. A combined quantitative and qualitative methodological approach was used to determine if the attitudes of teachers towards Black girls maintain racial barriers that have been found in education.

Exploring Faculty Perspectives Of Roadblocks To Accommodating Students With Disabilities In Community Colleges, Shalither S. Cushenberry

Dissertations

This qualitative study explores faculty perspectives on student accommodation in the community college setting. The one-on-one, semi-structured, in-depth interviews with faculty and perspectives of accommodation experts will result in outcomes that better prepare faculty, as a workforce, to support students with accommodations. The study utilized the social cognitive career theory (SCCT) to understand how increasing faculty awareness and engagement through professional development can enhance their ability to provide services to students with accommodation requests. The study underscores the critical importance of understanding the rationale for students with granted accommodations and faculty members supporting their academic success. The findings revealed gaps …

Summer Melt: The Transition Of Rural Students To Post-Secondary Schools, Niquan Alston

Dissertations

Rural high-achieving students face unique challenges as they prepare to transition to college. While many graduate with aspirations for higher education, a significant number fail to transition to college in the fall due to barriers that arise between high school graduation and college enrollment. Rural schools, particularly those serving low-income populations, frequently lack the resources, counseling, and exposure opportunities that help students navigate the transition from high school to postsecondary education. These circumstances leave students to manage financial barriers, incomplete paperwork, limited support, and the pressures of balancing family and community responsibilities. Their lived experiences shape the way they respond …

A Joint Mindfulness And Growth Mindset Intervention For Reducing Math Anxiety For Pre-Service Elementary Teachers, Evan Czysz

Dissertations

Pre-service elementary teachers (PSTs) have often exhibited high levels of math anxiety, which can negatively influence their confidence, learning, and future teaching in mathematical settings. The purpose of this phenomenological case study was to understand the influences an intervention focused on growth mindset and mindfulness-based practices has on preservice elementary school teachers’ perceptions of mathematics at a mid-sized university in the Rocky Mountain Region of the United States, and sought to answer the following questions: Q1 Does a joint mindfulness-based and growth mindset intervention impact pre-service teachers’ levels of math anxiety? Q2 What were pre-service elementary teachers’ experiences with a …