Digital Commons Network^™

Distribution And Ecological Effects Of Azteca Chartifex/Trigona In The Barro Colorado Nature Monument., Rachel Leann Wells

Electronic Theses and Dissertations

This dissertation explores the behavior and ecology of a conspicuous and behaviorally dominant ant species in the tropical rainforest of Panama. Competition with aggressive species is an important factor that shapes local community structure. Eavesdropping on the chemical communication systems of such behaviorally dominant species can help heterospecific species to avoid negative interactions. I review the chemical communication system and known ecological effects of the Neotropical canopy ant, Azteca chartifex/trigona (Chapter 1). There are over 40 known compounds produced by Azteca workers, yet how these compounds impact heterospecific species is unclear in many circumstances. I assessed if heterospecific …

In Bloom: Nurturing The Liberation Process Of Performer And Character As Rose In August Wilson's Fences., Paula O. Lockhart

Electronic Theses and Dissertations

Rose Maxson is the 43-year-old matriarch of the Maxson household in August Wilson’s Pulitzer Prize-winning play, Fences. She is a character with an inviolable spirit. The unwavering force she possesses rattles the pages as she relives past loves, loss, experiences heartbreak. Imagine, how I, a then 24-year old devoid of the immense life experience that Rose encompasses found my way into her. The answer is through nurture. To nurture is a process of feeding, protecting, or rearing someone or something. It is a journey with or without a destination. Rose is in a constant state of nurturing her family, …

Development And Applications Of In-Vitro And In-Silico Models Of The Cardiovascular System To Study The Effects Of Mechanical Circulatory Support., Moustafa Meki

Electronic Theses and Dissertations

Cardiovascular diseases (CVDs) are the leading cause of mortality globally. With ongoing interest in CVDs treatment, preclinical models for drug/therapeutic development that allow for fast iterative research are needed. Owing to the inherent complexity of the cardiovascular system, current in-vitro models of the cardiovascular system fail to replicate many of the physiological aspects of the cardiovascular system. In this dissertation, the main concern is with heart failure (HF). In advanced HF, patients may receive Left Ventricular Assist Devices (LVADs) as a bridge to transplant or destination therapy. However, LVADs have many limitations, including inability to adapt to varying tissue demand …

Assessing The Role Of Chronic Arsenite Exposure In Disrupting The Egfr Signaling Axis., Christine Kim

Electronic Theses and Dissertations

Chronic arsenic exposure is a risk factor for the development of pulmonary diseases, including lung cancer, but the exact mechanism is not yet fully understood. Many previous studies have relied on acute arsenic exposure (i.e. 1-10 uM arsenic for 24 hours) to study arsenic toxicological effects. However, acute exposure does not reflect the levels or duration of arsenic associated with environmental exposure, or drinking of contaminated well water. This dissertation differentiates the effects of acute versus chronic arsenic exposures on the EGFR signaling axis and suggests possible mechanisms for chronic arsenic-induced pulmonary diseases. The EGFR is a receptor tyrosine kinase …

Mapping Three Dimensional Interactions Between Biomolecules And Electric Fields., Joseph Patrick Brian P.E.

Electronic Theses and Dissertations

Electroporation is a technique that induces the formation of open pores in cell membranes by the application of an electric field. Electroporation is widely practiced in research and clinical work for transfection of genetic sequences and drug molecule transport through the membrane barrier. However, a full theoretical explanation of the molecular mechanisms and thermodynamics responsible for pore formation, structure, and longevity does not yet exist. Advances in molecular dynamics simulations have enabled theoretical studies of electroporation with previously unobtainable fidelity spanning biologically relevant timescales. All-atom simulations utilizing the recently developed method of computational electrophysiology demonstrate that pore size correlates to …

Simulation Of Fracture Strength Improvements Of A Human Proximal Femur Using Finite Element Analysis., Waleed Ebraheem Alim

Electronic Theses and Dissertations

The most common hip fracture in the elderly occurs as a result of a fall to the side with impact over the greater trochanter resulting in a fracture of the proximal femur. The fracture usually involves the femoral neck or the intertrochanteric region. It has recently been determined that the fracture crack of a hip fracture typically initiates on the superior-lateral cortex of the femoral neck and then propagates across the femoral neck, resulting in a complete fracture. The strength of the superior-lateral cortex of the femoral neck is likely determined by the combined properties of the generally thin cortex …

The Importance Of Noncapped Viral Genomic Rna To Alphaviral Infection And Pathogenesis., Autumn Lapointe

Electronic Theses and Dissertations

Alphaviruses are mosquito-borne arboviruses that have a positive sense, single-stranded RNA genome, which are capable of causing severe disease and thus pose a significant burden to public health. During alphaviral replication, significant quantities of viral genomic RNAs that lack the canonical alphaviral 5’ cap structure are produced and packaged into viral particles, despite the fact that these noncapped genomes cannot be translated and are essentially noninfectious. The production and packaging of the noncapped genomes has been found to be true for infections across multiple vertebrate and invertebrate cell lines and alphavirus species, although the proportion of ncgRNA produced differs. Despite …

Role Of Kvβ2 Subunits In Regulation Of Resistance Arterial Tone., Sean M Raph

Electronic Theses and Dissertations

Voltage-gated potassium (Kv) channels control vascular resistance and facilitate the augmentation of myocardial blood flow in response to increases in cardiac workload (i.e., metabolic hyperemia). Native sarcolemmal Kv1 channels in arterial myocytes associate with a heteromeric auxiliary complex consisting of intracellular Kvβ1 and Kvβ2 proteins. The Kvβ proteins differentially regulate the function of heterologously expressed Kv channels, as well as native Kv1 channels in excitable cells of the cardiovascular and nervous systems. The physiological importance of vascular Kvβ proteins in mediating vasodilation remains unknown. In this study, I tested the hypothesis that Kvβ proteins functionally regulate vascular tone in response …

Preclinincal Development Of Avaren-Fc: A Novel Lectin-Fc Fusion Protein Targeting Cancer-Associated High-Mannose Glycans., Matthew William Dent

Electronic Theses and Dissertations

This dissertation explores the anticancer activity of Avaren-Fc (AvFc), a novel lectin-Fc fusion protein or “lectibody” targeting cancer and virus-associated high-mannose glycans. Previously, we have shown that AvFc recognizes a broad selection of established cancer cell lines from a wide array of tissue types, can potently induce antibody-dependent cell-mediated cytotoxicity (ADCC) against them, and exhibits anti-cancer activity in vivo. However, the exact mechanism of action remains elusive. We hypothesized that the primary mechanism of action is through Fc-mediated effector functions, and the purpose of this dissertation is to explore this question through the use of Fc variants that either …

Vitamin B12 Deficiency Does Not Stimulate Amyloid-Beta Toxicity In A Ceanorhabditis Elegans Model Of Alzheimer’S Disease, Opeyemi F. Showemimo

Electronic Theses and Dissertations

Alzheimer’s disease (AD) is symptomized by amyloid-beta plaques in the brain and accounts for more than 65 percent of dementia cases. Vitamin B12 (cobalamin) deficiency can result in similar cognitive impairment and roughly 15% of the elderly are vitamin B12 deficient. Vitamin B12 deficiency results in the accumulation of toxic methylmalonic acid and homocysteine. Hyperhomocysteinemia is a strong risk factor for AD. To test if vitamin B12 deficiency stimulates amyloid-beta toxicity, Caenorhabditis elegans expressing amyloid-beta in muscle were fed either vitamin B12-deficient OP50-1 or vitamin B12-rich HT115(DE3) E. coli bacteria. Increased amyloid-beta toxicity was found in worms fed the …

Predicting Henry's Law Constants Of Volatile Organic Compounds Present In Bourbon Using Molecular Simulations., Christopher A Abney

Electronic Theses and Dissertations

Henry’s Law describes the partitioning of molecules into liquid and gas phases at low concentrations. Henry’s Law, which is based upon a species-dependent constant and the gas phase partial pressure, is useful for predicting phase behavior of dilute solutes. However, Henry’s Law constants are difficult to measure experimentally or to predict using structure-property or thermodynamic models. Herein, molecular simulations were used to calculate Henry’s Law constants for 18 volatile organic compounds (VOCs) present in bourbon. The novel simulations analyzed solvation thermodynamics of small organic molecules in 120 proof ethanol. A fast-growth non-equilibrium free energy method was used in which the …

Cfd Analysis Of Acoustofluidic Channels And The Effects On Biologic Delivery., Zachary T. Long

Electronic Theses and Dissertations

T-cell transformation is an ever-expanding treatment for several types of cancer, with a potential to be adapted to other disorders in which the immune system plays a key role in the pathophysiology. Currently, all FDA approved chimeric antigen receptor (CAR) T-cell cancer therapies rely on transformation via viral transduction. However, viral transduction is plagued by poor consistency and the potential to create adverse immune reactions when T-cells are reintroduced into a patient. Other transformation methods are being explored, with an alternative called acoustofluidic sonoporation showing promise. In these procedures, cells are passed through a channel, of the millimeter scale, while …

Automated Conversion Of Multicellds Digital Cell Lines And Isa-Tab Filesets., Connor Joseph Burns

Electronic Theses and Dissertations

Biological simulation tools are a valuable asset to bridge the gap between biological experimentation and biological theory. As systems thinking has become more regularly applied to biological materials and processes, these materials and processes have been characterized in multi-disciplinary, computational manners. This characterization has yielded an ability to create more realistic simulation tools that can provide in silico experiments for a wider range of scenarios. One prominent simulation tool is PhysiCell, an open-source physics-based multicellular simulation program which utilizes input Digital Cell Lines or Digital Snapshots from the MultiCellular Data Standard (MCDS) project.

This project aims to allow data exchange …

Image Analysis Of Charged Bimodal Colloidal Systems In Microgravity., Adam J. Cecil

Electronic Theses and Dissertations

Colloids are suspensions of two or more phases and have been topics of research for advanced, tunable materials for decades. Stabilization of colloids is typically attributed to thermodynamic mechanisms; however, recent studies have identified transport or entropic mechanisms that can potentially stabilize a thermodynamically unstable colloidal system. In this study, suspensions of silsesquioxane microparticles and zirconia nanoparticles were dispersed in a nitric acid solution and allowed to aggregate for 8-12 days in microgravity aboard the International Space Station. The suspensions were subsequently imaged periodically at 2.5x magnification. Due to the inadequacy of existing image analysis programs, the python package “Colloidspy” …

From Deficit To Strength: The Educational Influence Of Single Black Mothers On Their Sons’ Academic Achievement, Tyre’ D’Vallion Jenkins

Electronic Theses and Dissertations

The purpose of this study was to examine the lived experience of single Black mothers’ in supporting their sons’ academic achievement and to better understand their overall success. Historically, research that has been conducted on single Black mothers is viewed from a deficit lens (Copeland, 1977; Grier & Cobbs, 1968; Karon, 1958; Moynihan, 1965; Pettigrew, 1964). The role of single Black mothers has been grossly misunderstood, insinuating that they would be economically poor, uneducated, and lacked effective parenting skills. This study incorporated phenomenological and narrative methodologies, such as semi-structured interviews, focus groups, and observational field notes to capture the participants’ …

Agreement Level Of Running Temporal Measurements, Kinetics, And Force-Time Curves Calculated From Inertial Measurement Units, Austin Smith

Electronic Theses and Dissertations

Inertial measurement units (IMUs) and wearable sensors have enabled athlete monitoring and research to become more ecologically valid due to their small size and low cost. IMUs and accelerometers that are placed on the body close to the point of impact and that record at sufficiently high frequencies have demonstrated the highest validity when measuring temporal gait event moments such as ground contact time (GCT) and flight time (FT) as well as peak forces (PF) during upright running. While the use of IMUs has increased in the sport performance and athlete monitoring realm, the potential of the technology’s ability to …

Machine Learning Approaches To Dribble Hand-Off Action Classification With Sportvu Nba Player Coordinate Data, Dembe Stephanos

Electronic Theses and Dissertations

Recently, strategies of National Basketball Association teams have evolved with the skillsets of players and the emergence of advanced analytics. One of the most effective actions in dynamic offensive strategies in basketball is the dribble hand-off (DHO). This thesis proposes an architecture for a classification pipeline for detecting DHOs in an accurate and automated manner. This pipeline consists of a combination of player tracking data and event labels, a rule set to identify candidate actions, manually reviewing game recordings to label the candidates, and embedding player trajectories into hexbin cell paths before passing the completed training set to the classification …

The Role Of Src In Nsclc Cell And Lung Fibroblast Migration On 3d Cell-Derived Matrix., Austin M Krueger

Electronic Theses and Dissertations

Lung cancer is responsible for the most cancer deaths between males and females, with a 6% five-year survival rate. Cancer metastasis is one of the leading causes of lung cancer lethality. Our lab has developed a method to culture cells on cell-derived matrix (CDM) and study cell-ECM interactions. This study utilized multiple cell migration methods to investigate the migration of NSCLC cells and IMR90 lung fibroblasts, both together and independently, on 2D plastic and 3D CDM. Our results showed that inhibiting Src, a significant influencer of cell migration and member of integrin activation, blocked cancer cell migration on 2D and …

An Exploration Of Factors Related To Recidivism Rates Among Mentally Ill Parolees, Sierra Kitzmiller

Electronic Theses and Dissertations

Although criminality among mentally ill individuals is a well-documented phenomenon, limited research has focused on specific factors that need to be addressed to combat this issue. Utilizing the theoretical framework of Shaw and McKay’s (1942) Social Disorganization Theory, in conjunction with collective efficacy (Sampson et al., 1997) and social capital (Coleman, 1988), different factors were explored in an attempt to discover their relationship with recidivism. Using secondary data from Criminal Justice Drug Abuse Treatment Studies, variables such as homelessness, unemployment, and religious importance were analyzed in relation to rearrest rates from 889 parolees nine months post-release. Marriage, sex, and age …

“I Done Been Through Hell”: An Existential Phenomenological Study Of The Lived Experience Of Fathers Who Have Lost A Child, Dynisha Wigginson

Electronic Theses and Dissertations

The rise in American pediatric death led to a shift in pediatric end-of-life care from focusing care only on the dying pediatric patient to include focus on the family. Most literature has focused only on mothers’ experiences or the combined experiences of mothers and fathers. Fathers’ experiences at their child’s end of life, as an individual phenomenon, is overlooked and ignored. Hence, significant knowledge gaps exist related to the repeated exclusion of fathers’ individual experiences. This study aimed to begin to fill this gap. Using the lens of Merleau-Ponty, this existential phenomenological study aimed to describe the lived experiences of …

A Phenomenological Inquiry Exploring Parental Involvement At Alternative Schools In Eastern North Carolina, Irv Glenn Ii

Electronic Theses and Dissertations

The purpose of this phenomenological study was to discover the perceptions of caregivers and teachers regarding parental involvement at alternative schools in Eastern North Carolina. The lack of parental involvement at some schools is a systemic issue that involves continued efforts by school staff to include caregivers in promoting student success. The difficulties of engaging parents of alternative students result in little interaction between caregivers and educators. It is essential to understand how caregivers and educators perceive parental involvement and assess the quality of parental participation in an alternative educational setting. A qualitative research method was chosen to comprehensively examine …

Influence Of Student Characteristics, Class Size, And Instructor Characteristics In Online Student Success, Melody K. Edmonds

Electronic Theses and Dissertations

The purpose of this non-experimental quantitative case study was to compare the academic success of community college students over three academic years (2016-17 through 2018-19) before the onset of COVID-19 based on final grades and the influence of student factors, class size, and faculty characteristics using archival data from selected online and on-ground classes at a Middle Tennessee community college. Student factors reviewed include gender, full-time or part-time status, and age (traditional or non-traditional status). Instructor characteristics reviewed included full-time or part-time (adjunct) teaching status and tenure or non-tenure status of faculty. Institutional data for this study consisted of 44,568 …

Sarcopenia Screening By Registered Dietitian Nutritionists (Rdns) In The United States (U.S.), Madison Marcom

Electronic Theses and Dissertations

Sarcopenia is a disease of muscle wasting primarily seen in older adults. Although this term was first coined over three decades ago, there is a lack of consensus on a definition, screening criteria, and treatment protocol for sarcopenia. The primary purpose of this study is to determine whether registered dietitian nutritionists (RDNs) in the United States (U.S.) screen for sarcopenia. Study participants were recruited through a randomized email list and included RDNs throughout the U.S. Respondents completed a survey questioning knowledge of sarcopenia, screening tools and company protocols in place, and the need and desire for sarcopenia education. Data revealed …

Not All Pollinator Gardens Are Created Equally: Determining Factors Pertinent To Improving Pollinator Garden Effectiveness, Travis Watson

Electronic Theses and Dissertations

Increasing evidence documenting the decline of insect populations, resulting from increasing human disturbances has resulted in efforts to establish pollinator gardens to provide additional resources for insect populations. However, our understanding of biotic and abiotic garden characteristics important for attracting and sustaining pollinator diversity is limited. Here, we evaluated 17 pollinator gardens to evaluate the effect of five biotic and three abiotic garden characteristics on pollinator species richness, abundance, and proportional representation of four pollinator functional groups. Plant species richness positively influenced pollinator richness and negatively influenced flower visitation. Bombus proportional abundance responded to several variables (distance to vegetation, plant …

First-Generation Women Students’ Perceptions Of Support While Enrolled In Higher Education Institutions: A Phenomenological Study, Erin Blankenship Messmer

Electronic Theses and Dissertations

This phenomenological study used qualitative research methods to explore the perceptions of support first-generation women students enrolled in college have. Eleven first-generation women students who were enrolled in undergraduate and graduate programs across the United States completed one-on-one interviews with the researcher. The participants explained the support they felt from family, friends, and members of their college or university, as well as areas where further support could be given. In these interviews, key themes emerged, such as the roles of mentorship and emotional support, the need for financial assistance, the role of family in support and providing cultural capital, the …

If You Can Dream It, You Can Do It: Walt Disney’S Hero’S Journey To Professional Identity, Charles Mccoin

Electronic Theses and Dissertations

The purpose of this multi-method single-case study was to examine the application of Joseph Campbell's Heroic Journey model as a means of professional identity creation in the life of Walt Disney.

Walt Disney was an entrepreneur, cartoonist, filmmaker, inventor, studio head, and family man whose career stretched through the first half of the 20th century. Walt used his imagination and creativity to establish industry norms in the animation, film, television, and amusement park industries. Walt Disney's legacy and vision continue to be a viable influence within the Walt Disney Company today.

Campbell's Heroic Journey model was used as the theoretical …

Fanfiction: A Look Into The Disruptions Of Gender Identity Through Tropes, Stephanie Preslar

Electronic Theses and Dissertations

Fanfiction provides the unique opportunity to explore disruptions of heteronormativity through tropes. By exploring different fanfictions in the Soulmate AU, ABO Dynamics, and Mpreg tropes, the disruptions indicate a desire to explore gender, identity, and sexuality through queered characters. Male slash fanfiction provides the chance to examine the disruption of the heteronormative through the queering of male characters and placing them into situations that may embrace the feminine or a female-gendered experience. The situating of heterosexual male characters into queered roles allows an examination of how this disrupts canonical ideas of gender, identity, and sexuality. By reviewing the male slash …

Theranostic Nanoparticles Folic Acid-Carbon Dots-Drug(S) For Cancer, Godwin Kweku Babanyinah

Electronic Theses and Dissertations

This study aims to prepare theranostic nanoparticles (NPs) that are expected to increase cancer diagnostics and therapeutic efficacy. We prepared the NPs constituting carbon dots (CDs) as an imaging agent, folic acid as a targeting agent, doxorubicin (DOX), or gemcitabine (GEM) as chemotherapy agents. The NPs include noncovalent FA-CDs-DOX, covalent CDs-FA-DOX, and covalent FA-CDs-GEM. Through ultraviolet-visible spectroscopy, fluorescence spectroscopy, and Fourier transform-infrared spectroscopy, the fabrication of these NPs was confirmed. It was discovered that the high drug loading efficiency is the noncovalent series while the high drug loading capacity is the covalent series The in-vitro pH-dependent drug release data indicate …

Hemin Utilization In Rhizobium Leguminosarum Atcc 14479, John Lusby

Electronic Theses and Dissertations

Rhizobium leguminosarum is a Gram negative, motile, nitrogen-fixing soil bacterium. Due to the scarcity of iron in the soil bacteria have developed a wide range of iron scavenging systems. The two types of iron scavenging systems used are indirect and direct. In-silico analysis of the genome identified a unique direct iron scavenging system the Hmu operon. This system has been identified in other closely related rhizobium species and is believed to be involved in utilizing heme compounds as a sole source of iron. We have attempted to characterize the role of the Hmu operon in iron utilization by monitoring the …

Effects Of Respiratory Perturbations On Aging And Healthspan In Daphnia Magna, Millicent Nkiruka Ekwudo

Electronic Theses and Dissertations

Aging is a degenerative process characterized by a decline in physiological functions and cellular activities. Environmental and pharmacological interventions affecting longevity pathways have been extensively studied in model organisms. This study investigated the effect of chronic mild intermittent hypoxia (4 mg O2/L) or mild mitochondrial uncoupling with three doses of 0 (control), 0.1, 1, and 5 μM of 2,4-Dinitrophenol (DNP), on life history and gene expression in four clones of Daphnia magna. Interestingly, clones from intermittent ponds displayed better tolerance to hypoxia and DNP. Although neither treatments extended longevity, hypoxia increased fecundity and body size, and decreased food consumption and …