Digital Commons Network^™

Quantifying Impacts Of Climate Change On Headwater Streamflow Regime In Robinson Forest: Insights From 35-Years Of Data Collection., Lauren Brown

Electronic Theses and Dissertations

Climate change may shift patterns of streamflow permanence in headwater systems by altering the frequency, magnitude, duration, timing, and rate of change of surface streamflow, impacting both local ecosystems as well as regional water budgets and availability. While much uncertainty surrounds modeling-based methods to quantify the impacts of climate change on water budgets, long-term hydrologic data collected from headwaters in experimental research forests serve as critical evidence to reduce such uncertainty. The objective of this study is to quantify shifts in frequency, magnitude, duration, timing, and rate of change of streamflow in two headwater catchments with relatively little recent disturbance …

Building Efficacy In Special Educators: An Examination Of Basic Readiness Factors, Clarice Wright Edwards

Electronic Theses and Dissertations

This phenomenological study examined the perceptions of self-efficacy of elementary special education teachers (SETs) providing services for students with disabilities (SWD) in the general education classroom setting. Additionally, this study explored the effect of job-embedded supports and the skill sets deemed essential to meet the needs of SWDs. Understanding methods that can enhance the skill sets and pedagogical knowledge of SETs beyond teacher preparation can provide schools and school districts with opportunities to build highly efficacious teachers and improve student outcomes. Participants were asked about the perceived impact of teacher preparation programs on the self-efficacy of practicing SETs and about …

Publication Of Undergraduate Experiments, Development Of Additional X-Ray Crystallography Experiments, And Proof-Of-Concept Cyclopropanation Reactions, Alain Beauparlant

Electronic Theses and Dissertations

Single crystal X-ray crystallography instructional materials were developed using a variety of compounds including sugar, Epsom salt, pyrite, copper(II) acetate, and rhodium(II) acetate. Rhodium(II) acetate was reacted with a variety of functionalized benzonitriles, and when crystals were obtained, characterized using single crystal X-ray crystallography. Rhodium(II) acetate with adducts of 4-nitrobenzonitrile and 4-(dimethylamino)benzonitrile were also characterized using proton NMR spectroscopy and Fourier Transform Infrared Spectroscopy. Rhodium(II) acetate with adducts of 4-(dimethylamino)benzonitrile was used as a catalyst in a proof-ofconcept reaction to determine if it acts as a catalyst in cyclopropanation reactions. Further, the new rhodium(II) acetate dinitrile compounds were investigated to …

Synthesis Of Bacterial Glycerophospholipids For Biomembrane Model Studies: A Means To Advanced Biofuels, Felix Adulley

Electronic Theses and Dissertations

To reduce reliance on fossil fuels, sustainable biofuels are being pursued, especially advanced biofuels like 1-butanol that have higher energy content and greater compatibility with existing infrastructure than ethanol. A persistent challenge is the yield-limiting toxicity of biofuels and process solvents, such as tetrahydrofuran, to the microbes that ferment biomass into biofuel. The cell membrane is a focal point of toxicity, and understanding how it interacts with fuels and solvents is key to improving yield. Phospholipid bilayers are the core of biomembranes, and model biomembranes of defined composition provide the ideal platform for biophysical studies. To this end, glycerophospholipids characteristic …

Once Upon Online: Conversations With Professional Storytellers About Adapting From In-Person To Virtual Storytelling Performance, Leticia Pizzino

Electronic Theses and Dissertations

This study examines how professional storytellers negotiated a new storytelling stage—the videoconference platform—as they pivoted their careers during mandated shutdowns due to COVID-19. An examination of the literature reveals extremely limited research involving either professional storytellers or live virtual storytelling. After interviewing five professional storytellers, I analyzed their stories through narrative inquiry. Analysis revealed that the storytellers negotiated the limitations and affordances of Zoom and adapted their storytelling to successfully connect with their audiences. Through crafting a narrative of their stories, I was able to represent their emotions, unique experiences, and abilities to adapt to the online environment. Their stories …

Strategic Blended Learning: 9-12 Teacher Perceptions Of Digital Engagement Post Covid-19, Brandon D. Weaver

Electronic Theses and Dissertations

This quantitative study examined teacher perceptions on the relationship between technology, student academic behaviors, and performance in blended 9^th-12^th grade settings through pre-COVID-19 Pandemic and post-COVID-19 Pandemic learning experiences. This replicate study explored the relationship between teacher perceptions of student motivation and student autonomy and their relation to technology implementation in face-to-face instruction and blended learning environments. Particularly, this study analyzed how student motivation and student autonomy were affected by blended learning technologies and teaching strategies introduced after the onset of the COVID-19 Pandemic.

Data were examined to investigate teacher perceptions on the relationship between technology, student …

Intestinal Microbiome, Fecal Fermentation Profile, And Health Indices In Hiv Infected Men Versus Non-Infected Controls, Mary Andreae, Mary C. Andreae Mrs

Electronic Theses and Dissertations

Many HIV-positive (HIV+) males on Highly Active Anti-Retroviral Therapy (HAART) experience metabolic abnormalities, including Non-Alcoholic Fatty Liver Disease (NAFLD) and lipodystrophy. The intestinal microbiota and short chain fatty acids (SCFA), participate in bidirectional communication with their host. Dysbiosis in HIV+ males on HAART demonstrate a Prevotella-rich enterotype shaped by multiple factors including, medications, adiposity, diet, intestinal permeability, and lifestyle; our objective was to investigate these factors. 19 HIV+ and 21 HIV- males were enrolled. BMI and hip-to-waist ratio (H:W) were obtained, and FibroScan for liver health. Intestinal permeability markers Claudin-21, flagellin, and intestinal fatty acid binding protein (IFABP) in …

School Nurses And The Sexual Health And Education Of Public-School Students In Tennessee, Amy Wake

Electronic Theses and Dissertations

Tennesseans have been experiencing increasing rates of sexually transmitted diseases since the year 2000. Those rates are highest among those 15- to 24-year-olds. At the same time, Tennessee policy requires the teaching of abstinence as the primary form of sexual health education and emphasized the use of abstinence-only curriculum. The school nurse represents an available resource in the Tennessee public schools. The purpose of the qualitative study was to explore, describe, and interpret the perceptions and experiences of public-school nurses from rural, suburban, and urban areas of Tennessee related to the sexual health and sexual health education of students. School …

Electrodeposition Studies Of Gold Nanoparticles And Alginate Hydrogel Films., Harikrishnan Nambiathan Nambiar

Electronic Theses and Dissertations

This dissertation investigates the electrochemical deposition (ECD) and electrophoretic deposition (EPD) processes involving citrate (cit)-stabilized Au nanoparticles (NPs) and calcium alginate (Ca-Alg-Au NP) hydrogel films. The first part of the dissertation investigates the influence of NP size, surface area (SA) coverage, and ligand stabilizers on the electrochemical growth of Au on Au NPs, aiming to enhance our understanding of the growth process during the nucleation and growth of metal NPs. The growth kinetics depend on Au NP size (4 nm > 15 nm > 50 nm) for a constant SA coverage, as determined by the overpotentials for ECD. The growth rate increases …

What Discrimination? Christian Microaggression Rhetoric Against Nontheists, Nicole Dolfi Hall

Electronic Theses and Dissertations

Theories of microaggressions have been used in the last decade as a framework for studying subtle forms of discrimination against racial minorities and other marginalized groups. However, there is a dearth of research on the scope and types of microaggressions nontheists face. This qualitative study examines microaggressions against nontheists by interviewing 16 religious Christians on their experiences and opinions of the discrimination Christians and nontheists face. The narratives were analyzed for thematic patterns between the rhetoric used and the type of microaggressions employed. The study revealed nine categories of microaggressions. The findings also showed how experiences of discrimination, political viewpoint, …

Implementation Of Hierarchical And K-Means Clustering Techniques On The Trend And Seasonality Components Of Temperature Profile Data, Emmanuel Ogedegbe

Electronic Theses and Dissertations

In this study, time series decomposition techniques are used in conjunction with Kmeans clustering and Hierarchical clustering, two well-known clustering algorithms, to climate data. Their implementation and comparisons are then examined. The main objective is to identify similar climate trends and group geographical areas with similar environmental conditions. Climate data from specific places are collected and analyzed as part of the project. The time series is then split into trend, seasonality, and residual components. In order to categorize growing regions according to their climatic inclinations, the deconstructed time series are then submitted to K-means clustering and Hierarchical clustering with dynamic …

Computational Quantum Chemistry Studies Of The Stabilities Of Radical Adducts Formed During The Oxidation Of Melatonin Derivatives, James Horne

Electronic Theses and Dissertations

Melatonin is a natural antioxidant that has been investigated for properties as a potential spin trap to identify short-lived free radicals. Computational quantum chemistry studies have been performed for the oxidation of melatonin to N¹-acetyl-N²-formyl-5-methoxykynuramine. This research focused on modification of melatonin into derivatives and analyzing the change in total molecular energy from melatonin to its oxidation product, as well as the corresponding derivatives. Each of the molecular geometries were optimized at the DFT/B3LYP/6-31G(d), DFT/B3LYP/cc-pVXZ (X = D, T), HF/6-31G(d), HF/cc-PVXZ (X = D, T), MP2/6-31G(d), and MP2/cc-PVXZ (X = D, T) levels of theory. …

Community College Students' Perceptions Of Sense Of Community And Instructor Presence In The Online Classroom, Marla Cartwright

Electronic Theses and Dissertations

The purpose of this non-experimental, comparative, quantitative study was to determine if there were significant differences between the perceptions of male and female community college students about the importance of sense of community (SoC) in online classes and sense of instructor presence (IP) at eight southern, public, community colleges using survey data. It was the intent of the study to determine if there were significant relationships of students’ perceptions of the presence of sense of community in online classes among factors of age, race, grade point average, cumulative credit hours, credential type, major area of study, and number of previous …

Obstetric Violence And Postpartum Adjustment: Exploration Of Risk And Resilience Factors, Hope O'Neill

Electronic Theses and Dissertations

Obstetric violence includes acts of abuse, coercion, or disrespect that occur during the labor process. The present study explores how obstetric violence impacts a person’s postpartum psychosocial adjustment. This study used a subset of data (N = 339) from a larger online study, which attempted to explore multiple facets of a person’s postpartum health. The psychological constructs examined are postpartum depression and postpartum anxiety. Additional constructs assessed were protective and risk factors: self-compassion and medical mistrust. Self-compassion and medical mistrust were examined by using moderation models. Additional analyses were completed using simple regression models to explore whether obstetric violence predicts …

Administrators’ Perceptions Of Alternatives To Suspension In Virginia Urban Public Schools, Hayley Poland

Electronic Theses and Dissertations

The purpose of this phenomenological study was to examine the perceptions of the use of alternatives to suspension of high school administrators in Virginia urban public schools. The phenomenological research design allowed better understanding of the participant’s view and perception of their use of alternatives to suspension. While there is research focusing on the use of alternatives to suspension, there has been little research in Virginia urban public schools on the perceptions of administrators on the use of alternatives to suspension. The framework this research study utilized to focus the data analysis was Social Learning Theory.

Data collection strategies included …

Papa Was A Missing Stone: An Exploration Into The Lived Experiences Of Father-Absent African American Women, Jamila Jordan Moody

Electronic Theses and Dissertations

This qualitative phenomenological study examines the lived experiences of adult father-absent African American women to extrapolate from their stories the meaning they attached to the experience and to hear in their own words how they perceived the absence of their father shaped their lives and affected them socially, emotionally, behaviorally, and educationally. Twelve semi-structured interviews were conducted via Zoom audio-conferencing with adult African American women who ranged in age from 20-62 years of age living in various parts of the U.S. The findings of this study revealed that father-daughter relationship bonds held a special meaning to each participant as most …

College Commute Distance And Retention For First-Time, Community College Freshmen, Michael O'Hagan

Electronic Theses and Dissertations

The purpose of this non-experimental, quantitative correlational study was to investigate whether any significant relationships existed between one-way student commute distance and retention for first-time, community college freshmen. Additional student success metrics such as three-year graduation rates, enrollment status, credit hours attempted and completed, and GPA were also analyzed for any possible relationship with commute distance.

Archival student data were collected from the participating institution, a public community college in the southeastern United States with four separate instructional site locations. This study followed the incoming class of 2016, entering in the fall semester, through the end of their third year, …

Convolution And Autoencoders Applied To Nonlinear Differential Equations, Noah Borquaye

Electronic Theses and Dissertations

Autoencoders, a type of artificial neural network, have gained recognition by researchers in various fields, especially machine learning due to their vast applications in data representations from inputs. Recently researchers have explored the possibility to extend the application of autoencoders to solve nonlinear differential equations. Algorithms and methods employed in an autoencoder framework include sparse identification of nonlinear dynamics (SINDy), dynamic mode decomposition (DMD), Koopman operator theory and singular value decomposition (SVD). These approaches use matrix multiplication to represent linear transformation. However, machine learning algorithms often use convolution to represent linear transformations. In our work, we modify these approaches to …

Covid-19 Vaccine Uptake In The Hispanic And Latinx Communities Of Northeast Tennessee, Gabriela Abrego

Electronic Theses and Dissertations

This work addresses the underlying issues surrounding COVID-19 vaccine uptake in Hispanic and Latinx communities in the Northeast region of Tennessee. A qualitative, phenomenological research approach was used to conduct interviews and data from the interviews was used to inform a survey instrument. The interview guide in the qualitative phase of the study was based on the Health Belief Model (HBM) developed by Rosenstock (Rosenstock, 1974). A quantitative approach was then used by piloting the survey instrument in the study population. Common themes found through the interviews were: previous negative experience with COVID-19 vaccination, previous negative experience as a result …

Educators’ Perceptions Of Trauma-Informed Instructional Practices In One Northeast Tennessee School District, Alecia Burleson

Electronic Theses and Dissertations

The purpose of this qualitative phenomenological study was to investigate the perceptions of classroom-level educators regarding the application of trauma-informed instructional practices. This was achieved by evaluating educators' understanding of the influence of trauma on students, their level of familiarity with trauma-informed instructional practices, and their assessments of the effectiveness of these practices. Trauma refers to an individual's response to a single traumatic incident, a succession of traumatic events, or extended exposure to a traumatic event (SAMHSA, 2014). As awareness of the prevalence of childhood trauma has increased, it is acknowledged as a serious public health issue (Lang et al., …

Effect Of Macrophage Expressed Α7 Nicotinic Acetylcholine Receptor (Α7nachr) On Migration Of Macrophages During Inflammation, Kasey Keever

Electronic Theses and Dissertations

Sepsis is a life-threatening condition characterized by overwhelming inflammation, resulting in organ system damage, leading to a high mortality rate. Care in the clinical setting is supportive, and there are no approved sepsis-specific treatments. In septic mice, activation of the cholinergic anti-inflammatory pathway decreases cytokine secretion by leukocytes and improves survival. The cholinergic anti-inflammatory pathway is a reflex of the parasympathetic nervous system, converging on the α7 nicotinic acetylcholine (α7nAChR) at the surface of macrophages. Signaling through the receptor blocks NF-kB activation, thus cytokine secretion. Receptor activation has other effects on macrophages, including modulating their migration to …

Flavonol Glucosylation: A Structural Investigation Of The Flavonol Specific 3-O Glucosyltransferase Cp3gt, Aaron S. Birchfield

Electronic Theses and Dissertations

Flavonoid glycosyltransferases (GTs), enzymes integral to plant ecological responses and human pharmacology, necessitate rigorous structural elucidation to decipher their mechanistic function and substrate specificity, particularly given their role in the biotransformation of diverse pharmacological agents and natural products. This investigation delved into a comprehensive exploration of the flavonol 3-O GT from Citrus paradisi (Cp3GT), scrutinizing the impact of a c-terminal c-myc/6x histidine tag on its enzymatic activity and substrate specificity, and successfully achieving its purification to apparent homogeneity. This established a strong foundation for potential future crystallographic and other structure/function analyses. Through the strategic implementation of site-directed mutagenesis, a thrombin …

Early Pliocene Mice And Rats From The Gray Fossil Site Of Eastern Tennessee: Implications For The Evolution Of Cricetidae And Understanding Of The Past Ecosystem, Ziqi Xu

Electronic Theses and Dissertations

Cricetidae ranks as the second-most species-rich and abundant mammalian family, with limited studies on eastern North American records prior to the Pleistocene. While cricetids has been previously noted at the early Pliocene Gray Fossil Site (GFS), this study provides a detailed description of eight taxa: Postcopemys (two species), Symmetrodontomys, Oryzomyini, Peromyscus, Neotoma, Neotomodon, and Xenomys. Postcopemys is the most common cricetid taxon at GFS, followed by Peromyscus and Neotoma. These records expand the stratigraphic and geographic range of multiple genera. Distinctive morphological features of GFS taxa suggest presence of several new species. The …

Crossing The Pond: The Influence Of Southern Appalachian Old-Time On Contemporary Irish Music, Amanda Morgan

Electronic Theses and Dissertations

Numerous studies examine Irish traditional music influencing old-time music, but few examine the influence of old-time on contemporary Irish. As our societies become more global, folk music travels faster and becomes more open to influence. Thes influences can be heard in the music of “Alfi” and “Lankum,” two ensembles steeped in Irish traditional music.

This study defines common musical elements of old-time and examines the use of those elements in two recordings: Alfi’s, “Jubilee” and Lankum’s, “The Old Man from Over the Sea.” Much of my data comes from interviews with Irish and American musicians and my own professional knowledge, …

The Experiences Of Students During Covid-19 School Disruptions, Brandi Bullock

Electronic Theses and Dissertations

The purpose of this study was to identify the perceptions of educators with respect to student experiences between March 2020 and February 2021 related to academics, social-emotional health, and safety and security. Data collection strategies included one-on-one interviews with 12 educators in one East Tennessee school district. To qualify for the study, participants had to have taught during COVID-19 schooling disruptions and have taught either 1st, 2nd, 3rd, 4th, or 5th grade in the 2022-23 school year. Data analysis was based on Systems Theory (Laszlo & Krippner, 1998) and Change Theory (Fullan, 2020). The results revealed 5 key themes that …

Elucidation Of The Role Of Avocado Wri1 And Wri2 And Their Ability To Affect Oil Content And Composition When Co-Expressed With Pdat1 And Dgat1, Jyoti Ranjan Behera

Electronic Theses and Dissertations

Plants synthesize and store oil, mostly as triacylglycerols (TAG), in seeds that is transcriptionally controlled by WRINKLED1 (WRI1), an APETALA2 (AP2) transcription factor. Among the four Arabidopsis WRI paralogs, WRI2 is nonfunctional, while the others are expressed in a tissue-specific manner. Additionally, two rate-limiting enzymes, diacylglycerol acyltransferase (DGAT) and phospholipid diacylglycerol acyltransferase (PDAT) catalyze the terminal step in TAG assembly and contribute to oil accumulation. Avocado (Persea americana) mesocarp, a non-seed tissue, accumulates significant amounts of TAG (~70% by dry weight) enriched with heart-healthy oleic acid. The oil accumulation stages in mesocarp coincide with the high expression of …

Assessing Virtual Versus In-Person Experiential Learning And Medical High-Fidelity Simulation In Medical Student Pediatric Clerkship Training, Andrew Mitchell Berry

Electronic Theses and Dissertations

Simulation and experiential training have been incorporated into medical school training for decades. The utilization of medical simulations has become an invaluable tool in healthcare education and training. However, circumstances such as limited resources, geographical constraints, or global health crises may hinder the feasibility of conducting in-person medical simulations. In these scenarios, virtual medical simulations emerge as a compelling alternative. While there are many ways to accomplish experiential-based learning, many faculty and students feel Socratic learning styles provide the best learning experience.

As medical students had just finished a predominantly virtual preclinical year due to the COVID-19 pandemic, the research …

Ethanol Dysregulates Sirt1-Mediated Lipogenic Signaling Pathways Through Α4*-Nicotinic Acetylcholine Receptors In Hepatocytes., Caitlin Christina Wilkerson

Electronic Theses and Dissertations

Alcohol-associated liver disease (ALD) is a broad spectrum of diseases ranging from steatosis to severe hepatic cirrhosis, none of which have any FDA approved therapies. Downregulation of hepatic Sirtuin 1 (Sirt1) activity by ethanol has been shown to lead to an upregulation of the pro-lipogenic gene targets under its jurisdiction, resulting in increased lipogenesis and triglyceride accumulation. It was hypothesized that ethanol acts on α4*-nicotinic acetylcholine receptors (α4*-nAChRs) in hepatocytes to decrease Sirt1 expression, which ultimately dysregulates lipid metabolic homeostasis. Ethanol’s effects were investigated in cultured AML12 hepatocytes and in WT primary mouse hepatocytes acutely exposed to ethanol. Consistent with …

Connections Between Polyvictimization, Daily Stress, Emotion Regulation, And Mental Health Symptoms: An Ecological Momentary Assessment Study., Zoe L. Bridges-Curry

Electronic Theses and Dissertations

Background and Objectives: Individuals who experience polyvictimization, or victimization across multiple life contexts, evidence particularly severe outcomes across a range of mental health diagnoses. Preliminary evidence suggests that emotion regulation difficulties and stress sensitization effects may help explain observed links between trauma exposure and mental health symptoms. However, the use of between-subjects designs to address within-subjects processes – a common approach across this literature – can result in erroneous interpretation of findings. Moreover, widespread reliance on retrospective trait measures of emotion regulation, daily stressors, and mental health symptoms have limited insight into the ways that these processes unfold in daily …

Environmental Exposures And Aging., Daniel Chris Gomes

Electronic Theses and Dissertations

In recent years, research into air pollution has shown that exposure to certain components in air pollution, primarily PM2.5 can accelerate biological aging and thereby lead to increased susceptibility to multiple diseases. We hypothesize that prolonged exposure to air pollutants can result in premature aging leading to extensive tissue dysfunction and susceptibility to diseases. To examine this, we exposed mice to PM2.5 for 9, 15, and 21 days, then measured the telomere lengths, cellular senescence, and histone methylation patterns of multiple cell types. We found consistently increased telomere attrition, cellular senescence and advanced age-consistent histone methylation patterns in groups exposed …