Digital Commons Network^™

Analyzing The Effects Of Biodegradable Plastic Fragments On Maize Development And Defense Signaling, Ulysses Hampton

Theses

As plastic use shifts from non-degradable to biodegradable materials, the effects of biodegradable plastic fragments on crop physiology remain unclear. This study investigated how biodegradable plastic fragments influence maize development, transpiration, and defense signaling. Among five plastic types tested, poly(butylene adipate-co-terephthalate) (PBAT), polyhydroxyalkanoates (PHA), polycaprolactone (PCL), polylactic acid (PLA), and thermoplastic starch (TPS). PBAT and TPS showed the most significant effects and were selected for further oxylipin analysis. Results indicate that biodegradable plastic fragments can alter oxylipin signaling pathways in subtle but meaningful ways, suggesting that these materials are not inherently risk-free alternatives to conventional plastics.

Ramsey Chains In Graphs, Ritabrato Chatterjee

Dissertations

The research in this work deals v-rith decomposition of graphs and Ramsey theory, two popular areas of research in graph theory due to numerous fascinating problems and the sheer mathema ical beauty of the subjects. A decomposition {G1 , G2 , ... , Gk} of a graph G into subgraphs of G is ascending if the subgraph Ci is isomorphic to a proper subgraph of G;+1 for i = 1, 2, ... , k - l. The well-known and long-standing of Ascending Subgraph Decomposition Conjecture states that every graph has an ascending subgraph decomposition, that is, the subgraphs (links) in …

The Impact Of Using History On Learning In Physics Laboratory Settings, Patrick W. Clouse

Dissertations

Integrating History of Science (HOS) into science courses has many benefits. Students demonstrate improved scientific content knowledge, develop their understanding of Nature of Science (NOS), and improve their attitudes towards science. However, barriers prevent instructors from effectively incorporating history into their teaching. The traditions and culture of science instruction, individual teacher attitudes and skills, existing institutional frameworks, and prevailing curricular materials all prevent HOS integration. Preservice teachers may never be exposed to HOS in their science or education courses, meaning they lack experience and knowledge surrounding the benefits of HOS. Therefore, alternative avenues for effective integration should be considered to …

“Dynt Of Dede:” Reading The Medieval Combat Scene Through The Helmet-Cleave Motif, Andrew Sherwood Thomas

Dissertations

This research explores the continuity of chivalric combat descriptions throughout medieval literature. By tracing the history, development, and distribution of the helmet-cleave motif, this study is able to examine combat scenes spanning a wide reach of time, genera, and language. The purpose of this work is to suggest a reading methodology for the chivalric combat scene that appropriately situates it in its cross-textual context and so reveals the nuance of its expression and the value in its study.

Despite the volume of surviving combat descriptions in medieval literature, they remain underrepresented in the scholarship due to their apparent repetitious and …

Modulating Linear Frequency Modulated Pulses To Send Communications Data In A Bistatic Sar Scenario, Jarren T. Worthen

All Graduate Theses and Dissertations, Fall 2023 to Present

Synthetic aperture radar (SAR) is the technology that enables the creation of images using radar waves, allowing images to be formed regardless of weather. In bistatic SAR a radar platform uses a radar pulse from a separate platform to form an image. It is important that these radar systems are able to communicate with each other. Rather than wasting energy and space flying with a separate communication system, the radar systems could use the already existing SAR system to send data between each other while still forming SAR images. The work of this thesis is to show how very simple …

High-Throughput Characterization Of Creep In Additively Manufactured 316l Stainless Steel, Raushan Kumar Singh

All Graduate Theses and Dissertations, Fall 2023 to Present

Advanced materials are widely used in industries such as nuclear energy, aerospace, and automotive engineering, where components are exposed to extreme temperatures and stresses over long periods of time. As new materials continue to emerge, researchers need efficient ways to evaluate their mechanical performance so they can be used safely and effectively. Among several mechanical challenges, creep is a major concern in these conditions. Creep is a type of mechanical failure in which materials gradually deform when exposed to high temperatures and constant load. Conventional methods for evaluating creep typically involve testing a single specimen at a time, which can …

Magnetic Properties And Ultrafast Spin Dynamics In Quantum Materials, Trung Kien Mac

All Graduate Theses and Dissertations, Fall 2023 to Present

Modern electronics mostly work by moving electric charge, which generates heat and hence wastes energy, especially as devices become smaller and faster. An alternative is to use the spin of electrons (a tiny magnetic property) and related “valley” states in certain atomically thin materials to store and process information more efficiently. This thesis explores how magnetism and spin behavior can be created and measured in a family of ultra-thin materials known as van der Waals quantum materials. Three kinds of materials are studied. First, atomically thin semiconductors are shaped into narrow nanoribbons. Because of their narrow size, their edges can …

'Fast' And 'Slow' Water Handling Strategies Explain Pinyon Pine Decline And Juniper Expansion, M. Faraz Rehman

All Graduate Theses and Dissertations, Fall 2023 to Present

Across the western United States, pinyon and juniper woodlands are changing with pinyon pine trees dying back while juniper becoming more abundant. Previous studies suggested that pinyon may lose more water during drier periods. But water loss is only part of the story. Water inputs, or how plants absorb water, are also likely to be important, but rarely well understood. To better understand this, we measured how pinyon and juniper absorb water from different soil depths and how actively they lose water through their leaves. Measurements were made over two years at three sites that ranged from more dry to …

Investigating The Role Of Patient-Provider Interaction Quality And Illness Interference In Patients' Basic Psychological Need Fulfillment And Subjective Well-Being, Rebecca Erin Elwood

All Graduate Theses and Dissertations, Fall 2023 to Present

Patient-provider communication occurs between patients and medical professionals. This type of communication is experienced by most U.S. adults yearly, and it can lead to positive health outcomes. The purpose of this study was to examine the role of this type of communication in patient’s lives overall. Specifically, the study considered if good quality patient-provider communication is associated with people feeling an overall sense of autonomy, competence, relatedness, and an overall positive experience of their life. It also considered how much symptoms or treatment of health issues impact people’s lives. Data in the study was collected through an online survey with …

The Evolution Of Hymenopteran Recombination Rates, Timothy John Delory

All Graduate Theses and Dissertations, Fall 2023 to Present

Individuals of some species mix their DNA frequently when producing sex cells, while others do so much less. Hymenopterans (ants bees and wasps) are especially useful for understanding this variation for several reasons. They show large differences in this frequency of shuffling, or rate of recombination, have well-studied genomes, and vary widely in how they live and reproduce. I capitalized on these features examines how recombination rates have evolved in this group at the trait, and gene level.

First, I revisited long-standing ideas about why recombination rates differ among these species, incorporating more than a decade of new research. This …

Theory, Implementation, And Practical Applications Of A Modern Parabolized Navier-Stokes Code, Logan B. Freeman

All Graduate Theses and Dissertations, Fall 2023 to Present

The Parabolized Navier-Stokes (PNS) method is a specialized computational approach for solving the equations that govern fluid flowing faster than the speed of sound, known as supersonic flow. By leveraging unique physical properties of supersonic environments—specifically that information cannot travel upstream—this method allows for significantly more efficient calculations than traditional approaches. Supersonic flows are important for many military and civilian applications including hypersonic weapons, high-speed passenger aircraft, and reentry. This thesis provides a comprehensive review of the two-dimensional PNS formulation, detailing the mathematical derivation and its practical implementation for solving flow problems. Through performance analysis and error assessment, this research …

Fibrous Protein Biomaterials: Characterization Of Solitary Bee Silk And Cocoons, And Development Of Recombinant Hagfish And Bee Silk Materials, Oran Wasserman

All Graduate Theses and Dissertations, Fall 2023 to Present

This dissertation explores two complementary aspects of fibrous protein biomaterials: the characterization of understudied naturally occurring solitary bee silk and cocoons; and recombinant expression and biomaterial formation of recombinant hagfish intermediate filaments (rHIF) and a single Osmia lignaria Say (Hymenoptera: Megachilidae) silk protein. Some solitary bee species, which make up about 75% of all bee species, spin silk to construct protective cocoons during development. Despite the importance of silk and cocoons to the solitary bees' life history, their properties remain largely unexplored. This dissertation presents a novel method for isolating and testing individual silk fibers without interfering with the development …

Simulation Of Hypersonic Conditions In A Lab-Scale Environment Using A Hybrid Rocket With Nitrogen Cooling, Joshua R. Sorenson

All Graduate Theses and Dissertations, Fall 2023 to Present

Developing hypersonic vehicles requires testing under extreme heat, airflow, and pressure. Traditional facilities like shock tunnels and arc-heated wind tunnels are costly and slow to set up. This thesis proposes a simpler, low-cost method using a small-scale hybrid rocket motor as a gas generator. The rocket’s hot exhaust is directed onto the front edge of a scaled-down model that represents the nose of a hypersonic vehicle. This creates a realistic flow that matches both the intense heat energy and the pushing force experienced in high-altitude hypersonic flight. The setup allows easy measurement of motor performance, surface pressures, leading-edge temperatures, and …

Perceptions Of Situational Leadership Styles On The Behavioral Intervention Skills Of General Educators, Kendall Jordan Baethge

Electronic Theses and Dissertations

The researcher conducted the following study to describe the lived experiences and perceptions of general educators employed in a rural, central Texas school district. The study specifically inquired about the perceptions of leadership styles and strategies to successful behavior intervention strategies for inclusive general education classrooms. The problem addressed within the study was the growing diversity in general education classrooms ensuring inclusive opportunities to students with disabilities who exhibit challenging behaviors. The purpose of the study was to better understand those leadership styles currently being used and styles that are most appropriate to develop perceived self-efficacy and proficiency in behavior …

Teacher Self-Efficacy And Its Relationship To Student Achievement: A Quantitative Analysis Using Map Growth Data, Joseph T. Holzmann

Electronic Theses and Dissertations

One factor that has been widely studied is teacher self-efficacy. Teacher self-efficacy is often considered an indicator of teacher effectiveness and has been linked to a variety of positive educational outcomes. The purpose of this quantitative study was to examine the relationship between teacher self-efficacy and student achievement. Additionally, the study investigated whether teacher self-efficacy differed based on years of teaching experience, grade level taught, and subject area taught. The Teachers’ Sense of Efficacy Scale (TSES), developed byTschannen-Moran and Woolfolk Hoy, was used to measure teacher self-efficacy among 88 participants with corresponding student MAP Growth data available for analysis. Results …

Navigating The Dark Side: Emotional Labor's Impact On Hr Professionals' Wellness, Esmeralda Amelia Rendón

Electronic Theses and Dissertations

This qualitative descriptive study was designed to document and describe how female-identifying human resource (HR) generalist practitioners serving as sole or primary employee relations practitioners in small- to medium-sized organizations across the United States experience and manage emotional labor in their roles, cope with its demands, and how these experiences impact their wellness and perceptions of organizational support. Despite the centrality of emotional labor (EL) in human resource professionals’ (HRPs) roles, little was known about how HRPs in these underresourced environments cope with these demands. Data were collected through semistructured virtual interviews with eight participants and analyzed using Braun and …

Cultural Intelligence And Leadership: Examining School Principals’ Impact On Teacher Belonging, Retention, And Conflict Resolution, Quincy C. Commerford

Electronic Theses and Dissertations

The increasing diversity throughout the United States, especially reflected in the school system, has increased the need for school leaders who can effectively lead culturally diverse communities, and, specifically, for culturally diverse teachers. Cultural intelligence has gradually become a leadership competency alongside other intelligences, such as emotional and social, but little is known about how a school leader’s cultural intelligence affects culturally diverse teachers sense of belonging, their experiences with conflict, and overall teacher retention. In this study the researcher examined how a school leader’s cultural intelligence affects teachers’ sense of belonging in two culturally diverse secondary school settings. Using …

Drivers Of Employee Success And Productivity: Analyzing The Role Of An Executive Recruiting Intern, Hayden Raycher

Agricultural Economics and Agribusiness Undergraduate Honors Theses

For an experiential thesis over an internship experience in collaboration with the University of Arkansas and my advisor, Dr. Michael Popp, I collected data over a 9-month period relevant to my internship at Stout Executive Search, an executive recruiting firm. The purpose of the research was to explore the factors that influence productivity in a recruiting environment and provide quantifiable insights into the impact of different job-related achievements towards overall employee success. The research was initially designed to encompass evidence and commentary on training regimens and company culture, as well as job experience, with the latter becoming the sole focus …

The Effect Of Sustainable 3d Store Design On Consumer Online Shopping Behavior, Sophie G. Roussel

Apparel Merchandising and Product Development Undergraduate Honors Theses

Sustainability has become a significant factor in shaping consumer shopping habits. Companies are implementing 3D store designs to provide a more immersive and interactive experience. Further study is needed to investigate whether a sustainable, green-focused 3D storefront shifts consumers’ satisfaction with online shopping and their intention to buy products from a sustainable store. This study seeks to fill the research gap by examining how sustainable 3D store design influences consumer shopping behavior. Specifically, three distinct 3D store mockups were developed using Visual Retailing (VR) technology. The same number of visually appealing features, products, and store layouts was used to make …

A Primary Care Randomized Controlled Trial Investigating The Efficacy Of A Caregiver-Focused Prevention Program For Child Sexual Abuse, Cassandra Dukes

Dissertations

Child sexual abuse (CSA) affects 1 in 4 girls and 1 in 13 boys before the age of 18, resulting in significant long-term physical, emotional, and social consequences. Caregivers play a crucial role in preventing CSA by engaging in preventative behaviors with their children. Primary care settings may be an avenue through which to educate caregivers on their role in prevention of CSA. The present study used a randomized controlled trial (RCT) design to investigate the efficacy of a caregiver-focused educational program to prevent CSA, provided via integrated behavioral health (IBH) in a pediatric primary care setting. Participants (n=56) were …

A Quantitative Exploration Of Public School Teachers’ Colorblind Racial Attitudes And Their Teaching Practices, Lindsey Dopheide

Dissertations

Teachers play a significant role in shaping student’s academic experiences, social development, and understanding of race and diversity within school settings. Because schools function as important sites of racial socialization, teachers’ beliefs about race may influence how they interpret student behavior, respond to inequities, select instructional practices, and engage with culturally diverse classrooms. One framework that has received increasing attention within psychological and educational research is colorblind racial ideology (CBRI) which reflects the minimization or denial of the continuing significance of race and racism in society. Colorblind racial ideology has been identified in prior literature as a dominant framework for …

Knowledge, Physician Communication, And Psychological Predictors Of Willingness To Engage In Dementia Risk Reduction Across The Lifespan, Thomas Fisher

Dissertations

Dementia represents a growing global public health concern, with increasing evidence suggesting that a substantial portion of dementia risk may be attributable to modifiable lifestyle and health-related factors. However, relatively little is known about public knowledge of these risk factors, willingness to engage in dementia risk reducing behaviors, and psychological factors that may be associated with willingness. The present study examines these factors among adults living in the United States across the lifespan. Participants (N = 308) completed an anonymous online survey assessing dementia risk-factor knowledge, willingness to engage in dementia risk reducing behaviors, primary care provider communication regarding dementia …

Masculinity, Psychological Flexibility, And Machismo: An Initial Examination Of Relationships To Interpersonal Violence, Geraldine Granados Todd

Dissertations

Intimate Partner Violence (IPV) is a grave problem in many areas of the world. Latin American countries have some of the highest rates of IPV in the world. One factor potentially impacting these rates has been hypothesized to be traditional machismo. Machismo is a complex construct that has proven difficult to define. A substantial challenge lies in distinguishing the characteristics that are unique to machismo from broader masculine gender role norms. Additionally, machismo seems to have a more “positive” side to it, encompassing loyalty to family, honor, and responsibility. This has been coined caballerismo. Studies looking at the impact of …

The Weight We Carry: An Arts-Based Narrative Screenplay Of Academically Successful African American Male Students, Freddie Mcgee

Dissertations

The purpose of this study was to examine, understand, and creatively represent the stories of African American male college students from low-income backgrounds who were raised by single parents and were academically successful. Guided by the overarching research question — What are the stories of academically successful African American male college students from lowincome homes who single parents raised? — The study sought to understand how participants navigated institutional racism and systemic barriers while achieving academic success, and how they resisted deficit-based stereotypes and expectations in higher education.

This study employed a critical, arts-based, qualitative narrative inquiry approach grounded in …

Examining Ai Use Strategies Among Engineering Students: An Exploratory Quantitative Study, Jenny Lee Blonquist

All Graduate Theses and Dissertations, Fall 2023 to Present

Artificial intelligence tools like ChatGPT have quickly become part of everyday life for many people, including engineering students. This has raised concerns about the effects of students relying or over-relying on AI to help with their coursework. Are they still building the problem-solving and reasoning skills they will need as engineers? The purpose of this study is to understand not just whether engineering students use AI, but how they use it.

This research focused on two different ways students can use AI tools. 'Understanding-seeking' is when a student uses AI as a learning support such as asking thoughtful questions to …

Bridging Animal Production And Human Nutrition: How Production Ecology Shapes The Nutritional Quality Of Terrestrial Animal Foods And Human Omega-3 Status, Joseph Vinod Varre

All Graduate Theses and Dissertations, Fall 2023 to Present

The question at the center of this dissertation is simple: does the way food is produced change the quality of the food itself in ways that matter for human health? Across a series of studies on bison meat, eggs, and human dietary intervention, the answer was yes. This work began with a broad look at the modern food system and the nutritional consequences of industrialized diets. In particular, it focused on the growing imbalance between omega-6 and omega-3 fatty acids in the Western diet. This balance matters because omega-3 fats support heart, brain, and immune health, and diets high in …

Thermal Rating And Prediction Of Roadway-Embedded Power Electronics For Dynamic Wireless Power Transfer, Forrest D. Nichols

All Graduate Theses and Dissertations, Fall 2023 to Present

Electric vehicles can be charged while driving through wireless charging coils buried in the road surface. To avoid running expensive cables from roadside equipment to each charging pad, the electronics that control the power transfer can also be buried in the road. However, burying these circuit boards removes the ability to cool them with fans or flowing air, so the heat generated during operation must escape naturally into the surrounding road material. If the boards get too hot, components fail—a problem that has already been observed in prototype systems.

Predicting how hot each component on a circuit board will get …

Mining Time Series Shapelets And Association Rules For Solar Flare Prediction, Drew Watson

All Graduate Theses and Dissertations, Fall 2023 to Present

Solar flares are the largest explosions in the solar system; they are caused by changes in the Sun’s magnetic field. Strong solar flares can disrupt power systems, damage satellites, and interfere with radio communication, so improving flare prediction is important. This thesis develops a way to predict severe solar flares while also helping researchers understand why those predictions are made. The approach looks for short patterns in solar magnetic field data that are linked to future flare activity. It then studies how these patterns appear together and in what order they happen over time. By doing this, the research not …

Divergent Belowground Strategies Of Savanna Grasses Under Varying Fire Regimes, Abigail C. Schmidt

All Graduate Theses and Dissertations, Fall 2023 to Present

Savannas are unique ecosystems, where trees and grasses live together across the landscape, not quite forming full forests or open grasslands. The ability for trees and grass to coexist is largely the result of widespread disturbances, such as fire. Fire in savannas is largely thought of in how it maintains plants above ground, however, fire also plays a key role in ecosystem and plant processes belowground. First, fire can change how soil nutrients, namely phosphorus, are cycled. Phosphorus is a key nutrient that plants need to function, and plants acquire phosphorus through their roots. Frequent fire can enhance phosphorus availability, …

Viability Assessment Of Bovine Embryos: A Public Dataset And Deep Learning Baselines, Erfan Khayyati

All Graduate Theses and Dissertations, Fall 2023 to Present

Improving the success rates of cattle breeding is essential for sustainable agriculture, global food security, and high-quality livestock production. Currently, determining whether a lab-grown bovine embryo is healthy enough for a successful pregnancy requires highly trained experts to manually evaluate days of continuous time-lapse video footage. This process is not only incredibly time-consuming but also highly subjective; human reviewers often suffer from visual fatigue when tracking subtle, microscopic cellular changes over a seven-day period, leading to significant disagreement among even top experts on an embryo’s true potential. Furthermore, assessing bovine embryos is notoriously difficult due to their dark, lipid-dense cellular …