Digital Commons Network^™

Survival Models With Background Mortality, Shujie Chen

Theses and Dissertations

In this dissertation, we focus on studying three mixture cure models with background mortality. With the development of treatment, patients may be cured and suffer from other cause of death. The cure model with background mortality can measure the population cure which refers to the patients with comparable mortality with their counterpart in general population. Three types of survival models are investigated, including generalized odds rate (GOR) model, cure model with background mortality for right censoring and interval censoring, and extended illness death model via incorporating “cure” fraction. All methods are validated via comprehensive simulation studies and real data application. …

A Cross-Sectional Analysis Of Infectious Causes Of Congenital Morbidity And Mortality In Central America: Torch, El Salvador, Mary Katherine Lynn

Theses and Dissertations

The primary goal of this dissertation was to understand the prevalence of the most regionally salient TORCH pathogens among a group of perinatal women from a highly vulnerable region of El Salvador at the time of parturition. TORCH pathogens, that cause TORCH congenital syndromes, are classically defined as Toxoplasma gondii, other infectious causes of concern (Zika virus, malaria, human immunodeficiency virus, etc), Rubella virus, Cytomegalovirus(CMV), and Herpes Simplex Viruses. These infections can be passed from mother to fetus through the placenta or other perinatal routes and cause severe maternal and neonatal morbidity and mortality. This dissertation sought to understand perinatal …

Mouth Stuff, Jacob Connor Smith

Theses and Dissertations

The purpose of this thesis is to explore the idea of nuance in culturally oversimplified narratives, including fraught paternal relationships, sexual assault and non-consent dynamics, childhood and young adulthood LGBTQ+ experiences, and everyday life and mental health in the climate crisis. Drawing upon the 20^th century tradition of short poetry and minimalism, this thesis attempts to demonstrate the frustration of post-internet media culture’s fixation on providing a complete account of a complex issue in extremely limited linguistic space. This collection narratively demonstrates a night of insomnia, loneliness, and depression from sunset to sunrise as the speaker recalls various memories …

Reactive End Capped Polybenzimidazole Oligomers For High Temperature Thermosets And Improved Membranes For Electrochemical Devices, Caroline Marie Rohlfing

Theses and Dissertations

Polybenzimidazoles (PBI) are heterocyclic polymers that possess high thermal and oxidative stability. The inherent strength and chemical and thermal stability of PBI make it ideal for use in extreme environments; however, the current processing of PBI molded parts makes the process practically and economically unfavorable. These intrinsic properties make PBIs of particular interest for many industrial applications, varying from fabrics to membrane materials to molded parts. Processing these molded parts is extremely difficult, as the high glass transition temperature and extremely high melting point (>500°C) of PBI result in poor flow properties of PBI resins even at high temperatures. …

Coaching To Success: Moving From A Fixed Mindset To A Growth Mindset Through Positive Motivation, Shannon Dianna Ramirez

Theses and Dissertations

The purpose of this study was to explore my students’ belief perseverance and fixed mindset and help them shift toward self-determination and a growth mindset. Incorporating goal setting, positive intentions, and coachable techniques in my sixth-grade math class, I collected data through an observation journal, student artifacts, and pre and post assessments. I found that goal setting, positive intentions, and coaching techniques enabled students to shift from belief perseverance toward self-determination that will transfer into life outside of the classroom. My findings showed helping students move from a fixed mindset to one of growth is possible but takes time. Creating …

Advancements In Parametric Modal Regression, Qingyang Liu

Theses and Dissertations

This dissertation considers statistical inference methods for parametric modal regression models. In Chapter 1, we motivate the mode as the measure of central tendency instead of the median or the mean with an example. Following the motivational example, we include an overview of existing modal regression models. Later, in the same chapter, we explain advantages of the parametric modal regression models over existing nonparametric modal regression models. In Chapter 2, we address issues in statistical inference brought in by data contaminated with measurement error. With measurement error in covariates, statistical inference methods designed for modal regression models with error-free covariates …

Violence, Rebellion, And Compromise In Chinese Campus Cinema ----- The Comparison Of Cry Me A Sad River And Better Days, Chunyu Liu

Theses and Dissertations

This dissertation examines the social critiques in Chinese campus films by viewing their development and cultural context. Social Criticism, a prominent trend in Chinese cinema, addresses a wide range of widely concerned social issues, including education, romance, marriage, politics, environmental concerns, psychological repressions, etc. It appears that a Chinese mainland woman filmmaker and a Hong Kong professional director echo each other on the same theme. They are inspired by similar genuine events and share many similarities in the way they orchestrate the relationships and backgrounds of the characters. However, the two films retain their different characteristics. This thesis will discuss …

An Exploration Of Perinatal Stress And Associated Mental Health Of Transitioning First-Time Fathers, Timothy Reed Burkhalter

Theses and Dissertations

Becoming a first-time parent is a stage in life that can be full of excitement but also trepidation. Much common knowledge and research focus on the maternal experience. To add to this established knowledge, this phenomenological study will explore the perinatal stress experiences of transitioning first-time fathers in the U.S.

Semantics-Based Data Security Models, Theppatorn Rhujittawiwat

Theses and Dissertations

In this dissertation, we studied how an adversary could attack databases and how the system could prevent or recover from such an attack. Our motivation to improve the current security capabilities of database management systems. We provided better recovery capabilities of database management systems by incorporating data provenance. We also expand our study to express security and privacy needs of data in the Internet of Things (IoT) environments such as a smart home environment. For this, we proposed a stream data security model to theoretically represent the data in the IoT network. We built a dynamic authorization model on our …

High-Performance Wide Bandgap Semiconductor Power Modules Enabled By Advanced Two-Phase Mini-Channel Cooling, Bo Tian

Theses and Dissertations

There is a widespread need for high performance wide bandgap power modules in both commercial and military applications. However, given the rapid advancements of wide bandgap power module technology, conventional cooling solutions have not kept up and do not provide the thermal management performance needed for high power density. Based on the two-phase cooling approach, two-phase microchannels operating at low fluid flow rates with low pressure drops have huge potential in enabling higher power density applications. Several studies have illustrated the potential great advantages of two-phase cooling compared to single-phase cooling in terms of maximum device temperature, spatial thermal distribution …

Deep Learning Based Fault Diagnosis And Prognosis For Bearing, Guangxing Niu

Theses and Dissertations

Rolling element bearings are critical components in industrial rotating machines. Faults and failures of bearings can cause degradation of machine performance or even a catastrophe. Therefore, it is significant work to perform bearing fault diagnosis and prognosis (FDP) reliably and effectively. Diagnosis aims to detect and estimate the fault state of bearing in real-time. Prognosis aims to conduct a long-term prediction to predict the fault evolution and estimate the remaining useful life (RUL) of the bearing.

Deep learning (DL) based FDP methods have become an important branch of bearing FDP methods due to their powerful capabilities in feature automatic learning, …

An Examination Of Inter-Limb Functional Asymmetry After A Fatiguing Bout Of Exercise In High Level Soccer Players, Nestor Urrea

Theses and Dissertations

INTRODUCTION: Inter-limb functional asymmetries greater than 15% have been linked to a greater incidence of injury. Moreover, asymmetries greater than 10% have shown greater risk of injury and worsened sport performance, especially for strength and power capabilities, in athletes of multiple sports. Fatigue and sex are factors that seem to influence injury rates as well as greater asymmetries between limbs. This research project aims to investigate the effects of a fatiguing bout of exercise in strength and power inter-limb functional asymmetries in male and female soccer players. It was hypothesized that strength and power asymmetries are negatively affected after a …

Leveraging Automated Fiber Placement Computer Aided Process Planning Framework For Defect Validation And Dynamic Layup Strategies, Joshua Allen Halbritter

Theses and Dissertations

Process planning represents an essential stage of the Automated Fiber Placement (AFP) workflow. It develops useful and efficient machine processes based upon the working material, composite design, and manufacturing resources. The current state of process planning requires a high degree of interaction from the process planner and could greatly benefit from increased automation. Therefore, a list of key steps and functions are created to identify the more difficult and time-consuming phases of process planning. Additionally, a set of metrics must exist by which to evaluate the effectiveness of the manufactured laminate from the machine code created during the Process Planning …

Gluten Free Diet Ameliorates Si Enteropathy In Iga Deficient Mice, Ryan Albert William Ball

Theses and Dissertations

Secretory IgA is the most abundant antibody in the intestinal mucosal and functions as the first line of defense against pathogens and micro-organisms in the gut. Selective IgA deficiency is the most common form of antibody deficiency. Clinically, IgA deficient patients are largely asymptomatic, they are however at a higher risk of developing certain inflammatory conditions like Celiac disease; an SI-specific enteropathy triggered by exposure to dietary gluten. Interestingly, celiac patients are 10-15 times more likely to have an IgA deficiency. Recent studies have shown that IgA^-/- mice develop enteropathy specifically in the ileum. We confirmed this phenotype in …

Examining Associations Between Social Needs And Mental Health Among Youth And Young Adults With Diabetes, Andrea Danielle Brown

Theses and Dissertations

Household food insecurity (HFI) disproportionally affects people with diabetes living in the United States and is more likely to occur in households with children and in minority race/ethnicity households. Food insecure people with youth-onset diabetes likely have increased risk for poor mental health due to dealing with stress and cost related to diabetes management, especially if facing additional health-related social needs that intersect with HFI. If left untreated, poor mental health among youth and young adults (YYA) with diabetes can lead to diabetes-related complications, increased health care costs, and mortality. Yet few studies have examined associations between HFI and mental …

Portrayals Of Roman Catholicism In North American Children’S And Adolescent Literature Following Vatican Ii, Kathleen Anna Carroll

Theses and Dissertations

While American children’s literature scholars have analyzed issues of Christianity broadly, and there are many considerations of Roman Catholicism within European children’s literature scholarship, there is a lack of scholarly discourse regarding Roman Catholicism within children’s literature published in the United States. This dissertation considers how North American children’s and adolescent literature approach the issues that preoccupied North American Roman Catholicism post-Vatican II as well as how such portrayals have impacted readers’ understanding of the faith during this vital period of transition within the Church. Chapter 1 focuses on the way young adult literature published in the early 1970s addressed …

The Role Of Religious Coping Resources As Resilience Factors In The Relationship Between Stress And Health-Related Quality Of Life Among Black Americans, Sarah Grace Frary

Theses and Dissertations

Black Americans face health disparities due to a number of systemic barriers across individual, relational, environmental, structural and superstructural levels, and these barriers increase their likelihood of chronic illness and premature mortality. Addressing these disparities is urgently needed. Addressing health promotion through culturally relevant interventions has been shown to be more effective, and one target for health promotion is Health-Related Quality of Life (HRQoL), a multidimensional health indicator that aligns well with many Black Americans’ understandings of health. HRQoL is negatively related to chronic stress. This study aimed to identify factors for effective coping with chronic stress that are culturally …

Engineering Of Bio-Based And Synthetic Polymers: Synthesis And Application In Superabsorbent Materials And Antibacterial Agents, Jihyeon Hwang

Theses and Dissertations

A polymer consists of a large number of monomer units, which can be obtained naturally or via a chemical process called polymerization. Polymers are important materials that are used in our daily life. Life would not be possible without these polymers, either from plant biomass or petroleum-derived synthetic polymers. The substitution of petroleum-derived to biomass-based polymers has been highlighted to mitigate adverse environmental impact. However, the use of bio-based polymers is still a significant challenge for more demanding applications. In this dissertation work, the engineering of both bio-based and synthetic polymers and their properties are investigated.

In Chapter 1, the …

Leptin, Serotonin, And The Control Of Food Intake, Nicholas David Maxwell

Theses and Dissertations

Obesity has created a devastating public health crisis that severely affects both quality of life and exacerbates serious health conditions such as heart disease and diabetes. For this reason, better treatments are critical, yet there are very few. The systems that regulate our metabolism and food consumption are intricate, complex, and still poorly understood, as the brain integrates peripheral signals with central neural networks to control our energy balance. One of these peripheral signals, leptin, holds great promise as a way to treat obesity but has been ineffective in patients with obesity. Therefore, our goal is to better understand the …

A Randomized, Placebo Controlled, Double-Blind, Crossover Study To Evaluate The Effects Of Two Novel Hydration Beverage Formulas On Rehydration In Healthy Adults, Nathaniel David Rhoades

Theses and Dissertations

Intro: Dehydration is common in athletes and can lead to reductions in cognitive and physical performance. While there are many commercially available hydration beverages, most contain high amounts of CHO and are marketed as functional beverages. The purpose of this study was to determine the effects of two novel hydration beverage formulas (HMAA, HM) on hydration, cognitive performance, and time to exhaustion (TTE). Methods: Sixteen subjects (n=8 women, n=8 men) completed three experimental days where they consumed one of three conditions (HMAA, HM, or placebo) assigned randomly. The experimental protocol was completed in a heat chamber at 30-32℃ and 45-50% …

B-Cell-Specific Mhcii Promotes Host-Microbiome Symbiosis, Mary Melissa Roland

Theses and Dissertations

Classical major histocompatibility complex class II (MHCII) molecules are cell surface glycoproteins that bind and present peptide antigens on the surface of antigen presenting cells (APCs). MHCII:peptide complexes engage T cell receptors (TCRs) and CD4 co-receptors thereby facilitating cognate interactions between CD4+ T cells and APCs, which is responsible for the development of antigen-specific reactions and long-lived immunity; so called TD antibody responses. This is a critical step in the host’s response to pathogens, commensals, environmental stimuli and tumors. IgA is the dominant antibody isotype secreted into the gut and it is thought that most of the IgA in the …

In Her Possession And Keeping Revolutionary War Widows And The Politics Of Family Archives, 1820–1850, Riley Kathryn Sutherland

Theses and Dissertations

This thesis examines how Revolutionary War widows deployed family archives as partisan tools to claim pensions. By reconsidering the relationship between women, family archives, and state building, it challenges established understandings of revolutionary women, nineteenth-century political economy, and memory.

Revolutionary War pension laws ignited fierce partisan debates. Since pensions would require Congress to impose tariffs and assemble a fiscal bureaucracy, they were generally supported by Whigs and contested by Democrats. Knowing that, women tailored their applications to their partisan audiences. Widows often appealed to Whigs by requesting welfare, citing their poverty. But when addressing Democrats, they framed the pensions they …

Customer Discovery And Applied Research And Development For An Environmental Nanotechnology, Paul Michael Vecchiarelli

Theses and Dissertations

Technology transfer is a process by which an innovative technology, typically produced in a non-commercial setting such as academia, is developed into a potential market opportunity. The first phase of technology transfer, once a technology has been developed, is to identify a customer segment and determine a value proposition that describes what need the technology will fulfill for them. This phase has been systematized into a framework known as customer discovery. Success in customer discovery will indicate technological gaps, such as scale-up, prototyping, and realistic testing, that are needed to deliver the value proposition to the initial customer. Both phases …

Substance Use Disorder Treatment Among African American Men Living In The Rural South Of The United States, Serge Raoul Wandji

Theses and Dissertations

Substance use disorders (SUD) affect more than 40 million Americans. African American (AA) men are disproportionally affected by the negative health and social consequences of SUD, and men in rural areas may be particularly at risk due to disadvantaged socioeconomic conditions and persistent race-related stressors such as perceived discrimination. The overall purpose of this study is to advance the understanding of factors associated with SUD treatment acceptance and relapse potential among Southern rural AA men.

This purpose was achieved by determining differences in treatment acceptance and relapse potential by race and gender among rural residents admitted in a SUD treatment …

Ultra-Processed Food Consumption And Risk Of Liver Cancer, Longgang Zhao

Theses and Dissertations

Background: Studies have shown positive associations between ultra-processed food (UPF) intake and obesity and type 2 diabetes, two risk factors for liver cancer. However, the relationship between UPF intake and liver cancer has scarcely been studied. We aimed to evaluate the association between UPF intake and the risk of liver cancer in three prospective cohorts and further explore the role of genetic predisposition to fatty liver diseases and biomarkers of liver health on modifying the association.

Methods: We used data from the Nurses’ Health Study (1986-2012), the Health Professionals Follow-up Study (1986-2012), and UK Biobank (2006-2020). Diet was assessed with …

Stories From North Carolina Teachers Of Color: An Inquiry Of Racialized Experiences In The Workplace., Deborah Stephanie Harrison

Theses and Dissertations

Growing educational research shows that teachers of color are finding themselves working in racially hostile schools through experiencing racism from their White colleagues in explicit and inexplicit ways. There is a need to further categorize how North Carolina teachers of color are experiencing racism in the workplace and identify how they are affected by it through experiential knowledge and analysis underpinned by critical race theory. Through action research, this study’s goals incorporated the implementation and evaluation of a collaborative book as a method of intervention on the effects of racial trauma. The collaborative book presents full counternarratives of teachers of …

An Investigation Of The Galenic Influence On The Artistic Depiction Of Anatomical Concepts During The Renaissance, Fatima Amjad

Theses and Dissertations

The Renaissance era was a period marked by an intellectual and artistic resurgence in Europe, during which artists sought inspiration from Classical sources. This resulted in a move away from stylized medieval aesthetics and towards a renewed emphasis on accuracy and humanity in art. Renaissance artists developed art styles that emphasized perspective, proportion, and anatomy, creating more lifelike and naturalistic representations of the human figure and the natural world. The adoption of naturalism and individualism in the arts paired with the rediscovery and retranslation of ancient anatomical texts propelled artists and anatomists to deepen their understanding of the human body. …

Cultivating Community In A Sixth-Grade Classroom: An Action Research Study, Jennifer Weller Wells

Theses and Dissertations

Students who experience trauma bring this trauma to school with them in the form of exaggerated behaviors—acting out or withdrawing, being violent or extremely passive, or exhibiting rudeness or academic difficulty. Because students react to trauma in many ways, there is no one way for teachers to respond. The classroom community is vulnerable to the sheer unpredictability of behaviors. Grounded in ecological systems theory, whole-child theory, and compassionate teaching theory, this study explored my efforts to mitigate the results of trauma and increase the sense of community and well-being in my sixth-grade classroom. During the last few weeks of the …

Timing Deterministic Structural Model Updating Considering Impact And Fatigue Damage, Jason Michael Smith Jr.

Theses and Dissertations

Naval ship structures such as support trusses, hull sections, driving machinery, and load-bearing beams are subjected to various damage states that develop on short-term (i.e. impact) and long-term (i.e. fatigue) timescales. Naval structures fitted with a structural health monitoring system with damage detection abilities will enable appropriate real-time adjustments to the ships’ posture and control policies and thus have increased survivability and lethality. A digital twin can provide real-time condition assessment of naval structures when conjoined with a decision-making framework will increase naval ship survivability through informed response management. A fundamental challenge for the development of digital twins is reliable …

How Do They Do It: A Narrative Of Disabled Public School Instrumental Ensemble Conductors And Their Positive Working Relationships With Their Administrators, Lia Alexandria Patterson Snead

Theses and Dissertations

As the leader of the instrumental ensemble, the conductor’s role is important on and off the stage. Public school conductors have especially demanding jobs because they must act as a conduit between composer and ensemble as well as handle all administrative duties pertaining to running a music program. Subsequently, this results in a heavier workload than the average teacher. The demanding workload can add to any preexisting issues for disabled ensemble conductors who struggle at work due to insufficient support from their administrators. The lack of strong administrative support for disabled or impaired faculty and staff may be due to …