Digital Commons Network^™

New Reports Of Smilodon And Panthera From North American Cave Sites With Reviews Of Taxonomy, Biogeography, And History, Matthew Bushell

Electronic Theses and Dissertations

In this study, three new reports of large felids from the Pleistocene are presented and discussed. A single partial left dentary from Jawbone Cave represents the first confirmed presence of S. fatalis in east Tennessee and was sampled for radiocarbon dating. Wind Tunnel and Chilly Bowl Cave are among the first records of P. onca to be identified confidently from Arkansas. Chilly Bowl Cave also produced two trackways attributable to Panthera sp., one set potentially belonging to P. atrox. In addition to the description of these remains and the caves they were found in, taxonomic histories for both S. fatalis …

Non-Destructive Imaging Of Phytosulfokine Trafficking In Plants Using Fiber-Optic Fluorescence Microscopy, Bernard Abakah

Electronic Theses and Dissertations

Plants secrete peptide ligands and use receptor signaling to respond to stress and control development. Understanding these phenomena is key to improving plant health and productivity for food, fiber, and energy applications. Phytosulfokine (PSK), a sulfated peptide hormone, regulates plant cell division, growth, and stress tolerance via specific phytosulfokine receptors (PSKRs). This study uses fiber-optic fluorescence microscopy to elucidate trafficking of PSK in live plants. The microscope features two-color optics and an objective lens connected to a 1-m coherent imaging fiber mounted on either a conventional upright microscope body or 5-axis positioning system (X–Y–Z plus pitch and yaw). PSK and …

Assessing A Pandemic: Spatiotemporal Analysis Of Covid-19 In Tennessee School-Age Children, Omobolaji Olawuyi

Electronic Theses and Dissertations

This study is a spatiotemporal analysis of the COVID-19 pandemic in school-age children (5-18 years) in Tennessee, from 2020-03-19 to 2022-02-12. Trend Analysis, Emerging Hot Spot Analysis, and a time series revealed three significant waves in both age groups. Therefore, Change Point Detection at the county level was completed using six defined change points to identify the wax and wane of the three COVID-19 waves. Hierarchical Cluster Analysis grouped counties with similar change points into six clusters. No spatial pattern was observed in distribution of the six clusters, however, when each change point was evaluated separately, spatial autocorrelation was present, …

Early College High School: A Study Of Dual Enrollment Students' Academic Success Based On Classroom Environment, Cynthia A. Johnston

Electronic Theses and Dissertations

This ex post facto, causal-comparative, quantitative study examined variations in academic success of Early College High School (ECHS) students who completed a dual credit course in two separate classroom environments, specifically a high school classroom environment and a college classroom environment. The researcher sought to determine if a relationship existed between classroom environment and final grades of students enrolled in an ECHS. Students in the high school classroom environment sample completed a dual credit English 101 course in a high school classroom located in an ECHS, taught by a high school teacher who had been credentialed by the partnering community/technical …

The Rise Of Wavetable Synthesis In Commercial Music And Its Creative Applications, Garrett Norman Scroggs

Electronic Theses and Dissertations

Wavetable synthesis is a powerful tool for music creation that helps composers and producers develop their own unique sounds. Though wavetable synthesis has been utilized in music since the early 1980s, advancements in computer technologies in the 2000s and the subsequent releases of software synthesizers in the late 2000s and early 2010s has led to the increased presence of wavetable synthesis in commercial music. This thesis chronicles a historical overview of the use of wavetable synthesis in commercial music and demonstrates the accessibility and power that wavetable synthesis delivers in music creation. The demonstration portion of this thesis features two …

First Skulls Of Arctomeles Dimolodontus (Mustelidae: Melinae) From The Gray Fossil Site (Early Pliocene, Tn) Reveal Extreme Intraspecific Variation, Charles Bruce

Electronic Theses and Dissertations

Here, a morphological description of the extinct meline badger Arctomeles dimolodontus from the Gray Fossil Site (GFS), Tennessee is provided with comparison to extant Meles meles. Originally described solely on upper teeth of a single individual, the recovery of several crania and jaws provides a sample of at least five individuals, affording the largest known fossil sample in North America of the enigmatic Melinae. Examination of A. dimolodontus skull material reveals extreme intraspecific variation in previously identified diagnostic characters, highlighting the need for caution when identifying fossil taxa based on similarly fragmentary remains. Dental variation is likely a result …

Examining Teachers' Referral And Placement Decisions Of Hispanic Children For Gifted And Talented Programs, Guillermo I. Mendoza

Electronic Theses and Dissertations

This quantitative survey design study examined whether children’s ethnicity makes a difference in teachers’ referral and placement decisions in gifted and talented (G/T) programs. A total of 524 teachers from all over the United States who have taught or currently teach pre-kindergarten through 5th grade participated. The participants were randomly given one of six vignettes adapted from a previous similar study (Elhoweris et al., 2005). Participants answered whether the child described should be referred and placed into gifted and talented programs. All six vignettes described gifted and talented characteristics; the only differences were the children's ethnicity and socioeconomic status. Data …

Identifying Taphonomic Distribution Patterns At The Gray Fossil Site, Shawn Haugrud

Electronic Theses and Dissertations

Since the early days of the discovery of the Gray Fossil Site (GFS), meticulous efforts to preserve the spatial data were a priority. Direct surveying of fossils prior to recovery, as well as grid mapping the site, provided relative spatial data within a square meter. Such efforts meant that even fragments and microfossils, recovered during the screening operations and eventual concentrate picking, maintained some spatial data. Available spatial data are used to identify smaller deposits within the greater system, as well as non-random distribution patterns among a number of GFS taxa. Patterns are particularly pronounced in the large-bodied taxa, Teleoceras …

Identifying And Analyzing Multi-Star Systems Among Tess Planetary Candidates Using Gaia, Katie E. Bailey

Electronic Theses and Dissertations

Exoplanets represent a young, rapidly advancing subfield of astrophysics where much is still unknown. It is therefore important to analyze trends among their parameters to learn more about these systems. More complexity is added to these systems with the presence of additional stellar companions. To study these complex systems, one can employ programming languages such as Python to parse databases such as those constructed by TESS and Gaia to bridge the gap between exoplanets and stellar companions. Data can then be analyzed for trends in these multi-star exoplanet systems and in juxtaposition to their single-star counterparts. This research was able …

Narratives Of Existence And The Narrative Existence: Ontological Unity In The Border Trilogy And Quantum Theory, Rebecca Leigh Mcintosh

Electronic Theses and Dissertations

Because the humanities and the sciences approach philosophical questions in contrasting ways, the study of literature and the study of physical science are often viewed as unrelated realms of scholarly inquiry. Science aims to provide a methodological approach for gathering knowledge about the world, while the humanities focus on criticism or analysis of cultural artifacts. However, even though the conceptual frameworks applied in scientific study and literary study are often incompatible or remarkably divergent, their methods for conceptualizing and transmitting ideas are the same, for humanity understands the world and experience of this world through narratives composed of referential metaphors. …

A Qualitative Case Study On How The Transition To Remote Learning Affected Elementary Language Arts Instruction During The Covid-19 Pandemic, Matthew B. Bergman

Electronic Theses and Dissertations

Emergency remote learning (or remote learning) altered K-12 instruction and occurred during the COVID-19 pandemic in the spring of 2020. Mandatory lockdowns and social distancing efforts transformed face-to-face instruction into a new pedagogical model called emergency remote learning or remote learning. In this qualitative case study, I aimed to understand how third-grade language arts instruction was affected during the transition to remote learning during the COVID-19 pandemic from the perspective of general education teachers, learning support teachers, school administrators, and residential care providers. Additionally, the researcher used Moore’s (1997) transactional distance theory to investigate which strategies (methods, materials, and technologies) …

Special Education Teacher Attrition: K-12 Administrator Perspectives, Tia Alove Stevens-Hicks

Electronic Theses and Dissertations

Abstract

Teacher attrition is a significant contributor to the teacher shortages, with preretirement attrition accounting for two thirds of all attrition. Special education teachers leave teaching at significantly higher rates than their general education peers. In addition, there is a greater demand for special education teachers due to the increase in public school students requiring special education services. As a result, many K–12 administrators and other educational leaders often fill vacant positions with unqualified or new teachers with less experience than their predecessors. Special education teachers have reported that teachers who remained in their positions reported high levels of administrative …

Emotional Intelligence Of Leaders In Higher Education And Its Impact On Employees, Jenny R. De Los Santos

Electronic Theses and Dissertations

The purpose of this quantitative research study was to further understand the relationship between the emotional intelligence of faculty who have moved up into administrative positions and nonfaculty leaders within university academic affairs. Higher education institutions have a history of high employee turnover. There is a lack in the hiring process within higher education, and the lack of a hiring process causes difficulties when leaders go from faculty or staff roles to administrative and supervisory roles with little training on managing their emotions and employees’ emotions, hindering leaders from thriving in their leadership positions. The sampling was leaders from traditional …

Exploring The Indicators Of The Two Social And Emotional Learning Competencies And Their Relationship To Community College Grade Point Average, Arvinder Kaur Gill

Electronic Theses and Dissertations

This study was done to help understand how social emotional learning impacts student academics and performance for incoming freshmen college students. The study looks at students who have had some social-emotional learning versus those who have not had any social-emotional learning skills and if impacts them at a community college setting. Also, this study looked at the relationship between instructors and students and how instructors can play a positive role in student success. A student survey on incoming freshmen entering a community college was recorded along with instructor/professor interviews to get a better idea of student experiences and outcomes. The …

Reference Frames In Human Sensory, Motor, And Cognitive Processing, Dongcheng He

Electronic Theses and Dissertations

Reference-frames, or coordinate systems, are used to express properties and relationships of objects in the environment. While the use of reference-frames is well understood in physical sciences, how the brain uses reference-frames remains a fundamental question. The goal of this dissertation is to reach a better understanding of reference-frames in human perceptual, motor, and cognitive processing. In the first project, we study reference-frames in perception and develop a model to explain the transition from egocentric (based on the observer) to exocentric (based outside the observer) reference-frames to account for the perception of relative motion. In a second project, we focus …

Deep Learning For Power Flow Estimation And High Impedance Fault Detection, Kun Yang

Electronic Theses and Dissertations

My thesis is divided into two parts.

The first part is: “Optimal Power Flow Estimation Using One-Dimensional Convolutional Neural Network [1]“. Optimal power flow (OPF) is an important research topic in power system operation and control decisions. Traditional OPF problems are solved through dynamic optimization with nonlinear programming techniques. For a large power system with large amounts of variables and constraints, the solving process would take a long time. This paper presents a new method to quickly estimate the OPF results using a one-dimensional convolutional neural network (1D-CNN). The OPF problem is treated as a high-dimensional mapping between the load …

Small Gtpase Regulated Intracellular Protein Trafficking In Endothelium, Caitlin Francis

Electronic Theses and Dissertations

Intracellular protein trafficking is the movement of membrane-bound organelles to and from requisite locations within the cell. Small GTPases are a critical component to the spatiotemporal accuracy of intracellular trafficking pathways as they determine the specificity and direction of organelle transport. There exists over 150 small GTPases categorized into 5 sub-families and are employed across all cell types. Despite their universal expression and relevance to cellular function, small GTPases remain incompletely understood across tissue types. In various instances, the trafficking pathway of a particular Rab in one cell type may belong to a completely disparate pathway in another cell type. …

Unsupervised Learning Algorithm For Noise Suppression And Speech Enhancement Applications, Abdullah Zaini Alsheibi

Electronic Theses and Dissertations

Smart and intelligent devices are being integrated more and more into day-to-day life to perform a multitude of tasks. These tasks include, but are not limited to, job automation, smart utility management, etc., with the aim to improve quality of life and to make normal day-to-day chores as effortless as possible. These smart devices may or may not be connected to the internet to accomplish tasks. Additionally, human-machine interaction with such devices may be touch-screen based or based on voice commands. To understand and act upon received voice commands, these devices require to enhance and distinguish the (clean) speech signal …

A Unified Approach To Regression Testing For Mobile Apps, Zeinab Saad Abdalla

Electronic Theses and Dissertations

Mobile Applications have been widely used in recent years daily all over the world and are essential in our personal lives and at work. Because Mobile Applications update frequently, it is important that developers perform regression testing to ensure their quality. In addition, the Mobile Applications market has been growing rapidly, allowing anyone to write and publish an application without appropriate validation. A need for regression testing has arisen with the growth of different Mobile Apps and the added functionalities and complexities. In this dissertation, we adapted the FSMWeb [14] approach for selective regression testing to allow for selective regression …

Moving From Theory To Practice: Examining Teaching Mathematics For Social Justice In An Elementary School Classroom, Krystal Giles

Electronic Theses and Dissertations

Teaching mathematics for social justice is a distinctive approach to mathematics education that seeks to have students use mathematics to navigate their identities, understand their lived experiences, examine inequities, and become agents of change. Current research provides a rich explanation of what teaching mathematics for social justice entails. Still, there is a need for research that studies how to move from theory to practice. The purpose of this research study is to examine the experience of teaching mathematics for social justice within my fifth-grade mathematics classroom for myself and my students, analyze the extent to which students’ ethnic and academic …

Flood Hydrology In Tropical Coastal Catchments: Linking Watershed Dynamics To Mangrove Sedimentation, Shannon L. Jones

Electronic Theses and Dissertations

Coastal flooding is expected to be more frequent and severe from amplified flooding from sea level rise (SLR) and upstream anthropogenic activity, particularly in tropical regions. Improved hydrologic modeling and characterization are needed to better understand, predict, and manage flooding where these amplifications are expected. Yet tropical catchments are often ungauged or have limited hydrogeomorphic data. Thus, locally calibrated models that incorporate local knowledge and alternative data can be used to provide greater information. This doctoral dissertation quantifies relationships between land use, precipitation, discharge, and downstream sediment accretion in a representative ungauged catchment using a locally calibrated rainfallrunoff model validated …

Uncovering Zn2+ And Ca2+ Homeostasis And Crosstalk In Primary Hippocampal Neurons, Chen Zhang

Electronic Theses and Dissertations

Zn²⁺ has been suggested to act as an intracellular signaling molecule due to its regulatory effects on numerous protein targets including enzymes, transcription factors, ion channels, neurotrophic factors, and postsynaptic scaffolding proteins. However, intracellular Zn²⁺ concentration is tightly maintained at steady levels under natural physiological conditions. Dynamic changes in intracellular Zn²⁺ concentration have only been detected in cells exposed to pathologic stimuli or upon receptor ligand binding. In the first project of my dissertation, for the first time, we revealed that developing neurons fire spontaneous and synchronous Zn²⁺ spikes at a specific time window (from 14 …

Design, Determination, And Evaluation Of Gender-Based Bias Mitigation Techniques For Music Recommender Systems, Sunny Shrestha

Electronic Theses and Dissertations

The majority of smartphone users engage with a recommender system on a daily basis. Many rely on these recommendations to make their next purchase, download the next game, listen to the new music or find the next healthcare provider. Although there are plenty of evidence backed research that demonstrates presence of gender bias in Machine Learning (ML) models like recommender systems, the issue is viewed as a frivolous cause that doesn’t merit much action. However, gender bias poses to effect more than half of the population as by default ML systems are designed to cater to a cisgender man. This …

How Coteaching Impacts Student Academic Growth In Elementary School, Sally-Rose Cragin

Electronic Theses and Dissertations

The purpose of this study is to determine the effects of co-teaching on the academic achievement of elementary students in English Language Arts (ELA). The current body of research related to co-teaching is primarily qualitative and mostly inconclusive (Hurd & Weilbacher 2017). After the reauthorization of the Individuals with Disabilities Education Act (IDEA) in 2004, it is vital for educational institutions to implement research-based practices to support students with and without disabilities in their Least Restrictive Environments (LRE). This study took a quantitative approach and utilized a causal-comparative design to answer the question: How does a co-taught classroom in comparison …

Academic Performance Of Low Ses At-Risk Black And Latinx Students: A Case Study Of Teachers’ Perceptions, Shelly Lynn Anderson

Electronic Theses and Dissertations

This study determined the perspective of the teacher when researching low SES at-risk Black and Latinx students’ academic performance. Research, over the years, not only highlight reasons and evidence for the low academic performance and the struggles the low SES at-risk Black and Latinx students face. In addition, research also recommends educational interventions that are not effective in bridging the achievement gap of low SES at-risk Black and Latinx students in comparison to their wealthier, White counterparts. Previous research denotes that school districts desire to implement educational interventions for struggling learners; however, theories, strategies, and interventions often do not translate …

Numerical Study Of Owls’ Leading-Edge Serrations, Asif Shahriar Nafi

Electronic Theses and Dissertations

The silent flight ability of owls is often attributed to their unique wing morphology and its interaction with their wingbeat kinematics. Among these distinctive morphological features, leading-edge serrations stand out – these are rigid, miniature, hook-like patterns located at the leading edge of the primary feathers of their wings. It had been hypothesized that these leading-edge serrations serve as a passive flow control mechanism, influencing the aerodynamic performance and potentially affecting the boundary layer development over the wing, subsequently influencing wake flow dynamics. Despite being the subject of research spanning multiple decades, a consensus regarding the aerodynamic mechanisms underpinning owls’ …

Neural And Behavioral Evolution In An Eavesdropper With A Rapidly Evolving Host, Aaron W. Wikle

Electronic Theses and Dissertations

The diversification of animal communication systems is driven by many interacting factors. Unintended receivers play an important part in this process, yet little is known about their role in signal evolution. Flies of the genus Ormia are parasitoids of crickets and rely on acoustic cues to locate hosts. In Hawaii, selection imposed by Ormia ochracea has led to recent and rapid diversification in the songs of their host. Here, we compare neural and behavioral responses of Hawaiian flies to those of an ancestral population to understand the role of parasitoid sensory and behavioral variation in the evolution of host songs. …

Surviving The Serenade: How Conflicting Natural And Sexual Selection Drove Rapid Diversification Of Mating Signals In An Insect, James H. Gallagher

Electronic Theses and Dissertations

Understanding how the early stages of sexual signal diversification proceed is of critical importance because the nature of these microevolutionary dynamics can directly shape species trajectories and macroevolutionary patterns. Unfortunately, studying signal diversification is challenging because signals involve complex interactions between behavioral, morphological, and physiological components, many of which can only be measured in real time. Here we had the opportunity to directly study this process with the recent increase in sexual signal variation in Hawaiian populations of the Pacific field cricket (Teleogryllus oceanicus). In Hawaii, male song attracts both female crickets and a deadly acoustically orienting parasitoid …

Power System Dynamic Control And Performance Improvement Based On Reinforcement Learning, Wei Gao

Electronic Theses and Dissertations

This dissertation investigates the feasibility and effectiveness of using Reinforcement Learning (RL) techniques for power system dynamic control, particularly voltage and frequency control. The conventional control strategies used in power systems are complex and time-consuming due to the complicated high-order nonlinearities of the system. RL, which is a type of neural network-based technique, has shown promise in solving these complex problems by fitting any nonlinear system with the proper network structure.

The proposed RL algorithm, called Guided Surrogate Gradient-based Evolution Strategy (GSES) determines the weights of the policy (which generates the action for our control reference signal) without back-propagation process …

Quantification Of Nuclear Dynamics During Epithelial Remodeling, Noah De Leeuw

Electronic Theses and Dissertations

The morphogenesis of developing tissues is contingent on an extensive array of rearrangements in cellular shape, position and identity at large and small scales. One commonly used process to reshape tissues is the cell intercalation-driven elongation of a tissue in a common axis, in which rows of epithelial cells undergo oriented intercalation in a directional fashion. In most models of intercalation, cells are treated as homogeneous objects directed in their shape changes by cortical forces localized along cell-cell interfaces or tricellular junctions. However, less attention has been paid to how inhomogeneities in mechanical resistance of their own internal structures affects …