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Synthesis And Characterization Of Cobalt(Iii) Complexes And A Vanadium(Iv) Complex With Flavonoids As Ligands, Ethan Schroeder

Chemistry & Biochemistry Theses & Dissertations

For many years now, transition metal complexes have been used as favorable additional chemotherapeutic approaches to medicine that were previously unexplored in the literature. One well-known chemotherapeutic drug, cisplatin, has been applied, but is limited in use due to its toxicity to the cells and its undesirable side effects to humans. Newly developed cobalt-based complexes with ligands known as flavonoids are being used to fight cancer. Flavonoids, compounds mainly found in fruits and vegetables, are shown to have antioxidative and anticancer properties. Use of flavonoids as ligands in transition metal complexes, e.g., those with a Ru(II) metal center, have been …

Effects Of Chewing Time On Gastrointestinal Discomfort, Substrate Use, And Performance During Running, Thomas Geaney

Human Movement Studies & Special Education Theses & Dissertations

Previous research has shown that food particle size affects gastric processing. For example, food particles greater than 3 mm may delay gastric emptying under certain conditions. Delays in gastric emptying can be problematic during aerobic exercise, leading to nausea, bloating, fullness, and other gastrointestinal (GI) symptoms. In some cases, symptoms can be severe enough to negatively affect athletic performance. This study investigated the effects of manipulating chewing duration of carbohydrate sports bars on GI discomfort, physiological responses, and performance during endurance running. This crossover study recruited 12 male runners (age: 36.4 ± 7.2 years, VO_2peak: 57.2 ± 4.7 …

Exploring Methods To Reduce Stress In College Students: Dog-Assisted Therapy, Ashley A. Green

Psychology Theses & Dissertations

Many young adults find their college years to be highly stressful. The American College Health Association (2021) found 48% of college students reported moderate to severe levels of psychological stress. Research has found that chronic stress, commonly found in the college population, can adversely affect the health and academic performance of college students (Campbell & Svenson, 1992). Universities have begun experimenting with and adopting a variety of strategies to help students manage stressors associated with college attendance. These initiatives have included relatively well-researched procedures such as meditation and yoga as well as emerging practices. Recently, some colleges have begun testing …

Effects Of Physical Characteristics Of Placebos On Exercise Performance, Owen Sipes

Human Movement Studies & Special Education Theses & Dissertations

Previous research has shown that placebos can impact medical conditions such as irritable bowel syndrome and depression as well as elicit analgesic effects and improvements in certain exercise performances. These placebo responses occur from a variety of alterations to the placebo itself or through verbal suggestion of how helpful the placebo will be. This study aimed to observe whether changing the color and quantity of capsules can induce improvements in both vertical jump and hand grip strength. This deceptive, parallel study consisted of 28 participants, with a mean age of 24.9 (±4.3) years old, that were randomly assigned to receive …

Data-Driven Predictive Modeling To Enhance Search Efficiency Of Glowworm-Inspired Robotic Swarms In Multiple Emission Source Localization Tasks, Payal Nandi

Mechanical & Aerospace Engineering Theses & Dissertations

In time-sensitive search and rescue applications, a team of multiple mobile robots broadens the scope of operational capabilities. Scaling multi-robot systems (< 10 agents) to larger robot teams (10 – 100 agents) using centralized coordination schemes becomes computationally intractable during runtime. One solution to this problem is inspired by swarm intelligence principles found in nature, offering the benefits of decentralized control, fault tolerance to individual failures, and self-organizing adaptability. Glowworm swarm optimization (GSO) is unique among swarm-based algorithms as it simultaneously focuses on searching for multiple targets. This thesis presents GPR-GSO—a modification to the GSO algorithm that incorporates Gaussian Process Regression (GPR) based data-driven predictive modeling—to improve the search efficiency of robotic swarms in multiple emission source localization tasks. The problem formulation and methods are presented, followed by numerical simulations to illustrate the working of the algorithm. Results from a comparative analysis show that the GPR-GSO algorithm exceeds the performance of the benchmark GSO algorithm on evaluation metrics of swarm size, search completion time, and travel distance.

An Exploratory Examination Of The Cultural Understandings Of Communication Competence Among Nigerian Immigrant Adult Children, Fredous Gambo

Communication & Theatre Arts Theses

Although “communication competence” may be considered a trans-cultural concept, its unique meanings and practices across cultures have yet to be studied. Communication between parents and children in African households, for example, have often been associated with a restive and high level of control. Specifically in Nigerian households, a major critique of parenting communication styles is the necessity of continually seeking the permissions of a patriarchal and hierarchical family structure. When families immigrate, parents and children alike must navigate learning to communicate in the new culture while also seeking to preserve their culture of origin. Past research shows that adult immigrant …

Tidal Flooding In The Mid-Atlantic Region Of The Us: Water Quality Effects In The Lower Chesapeake Bay, Alfonso Macias Tapia

OES Theses and Dissertations

Many coastal areas around the globe suffer from nutrient pollution and its environmental, social, and economic consequences. Nutrient inputs can come from point (e.g., the end of a pipe) and nonpoint sources, from which the former are better constrained as sampling need only be conducted at a discharge point. Given the temporal and spatially extensive nature of tidal flooding events, they can represent another type of nonpoint source of nutrients to adjacent water bodies heretofore, unexamined and quantified. Most studies examining impacts of tidal flooding have focused on threats to resources on land, such as urban infrastructure and human health …

Examining The Relationship Between Spelling Achievement And Academic Achievement In Community College Students, Tambra Lee Riggs-Gutiérrez

Educational Leadership & Workforce Development Theses & Dissertations

The relationship between spelling achievement and academic achievement in community college students was investigated in this quantitative study. The research questions focused on whether a brief (under 15 minutes) spelling screening assessment may or may not predict student academic achievement of course grade points earned in an entry-level English class or cumulative grade point average. Demographic and descriptive data were also analyzed. A linear regression analysis design was used in this study. Participants for the study were 55 students from two geographically distant campuses of one community college in the Commonwealth of Virginia in the Mid-Atlantic region of the United …

Influence Of Abiotic Drivers And Plant Community Interactions On Bald Cypress (Taxodium Distichum) Seedlings: Implications For Restoration, Victoria Ellis

Biological Sciences Theses & Dissertations

Forested freshwater wetlands are valuable ecosystems that provide habitat for numerous species, sequester carbon, and act as sinks for excess water and nutrients. Historically, these ecosystems have been heavily degraded by anthropogenic activities leading to loss of ecosystem services and a desire to restore freshwater forested wetland habitat. Thus, science-backed approaches for the restoration of freshwater forested wetlands are necessary to ensure restoration goals are met. This body of research employed the Stress Gradient Hypothesis to test whether a multi-species planting approach using Juncus effusus (L.) (soft rush) could facilitate the survival of Taxodium distichum (L.) Rich. (bald cypress) seedlings …

Ultrasensitive Tapered Optical Fiber Refractive Index Glucose Sensor, Erem Ujah

Biomedical Engineering Theses & Dissertations

Refractive index (RI) sensors are of great interest for label-free optical biosensing. A tapered optical fiber (TOF) RI sensor with micron-sized waist diameters can dramatically enhance sensor sensitivity by reducing the mode volume over a long distance. Here, a simple and fast method is used to fabricate extremely sensitive refractive index sensors based on localized surface plasmon resonance (LSPR). Two TOFs (l = 5 mm) with waist diameters of 5 µm and 12 µm demonstrated sensitivity enhancement at λ = 1559 nm for glucose sensing (5–45 wt%) at room temperature. The optical power transmission decreased with increasing glucose concentration due …

Age-Related Differences In Motor Performance, Jessica Anne Prebor

Rehabilitation Sciences Theses & Dissertations

The purpose of this work was to study the age effects on average performance and variability of movement responses in children, young adults, and older adults across multiple motor tasks. Optimal motor performance is observed in healthy young adults with declines observed at either end of the lifespan. This pattern has been represented as a U-shaped/inverted U-shaped curve. Little is known about if this pattern persists in chewing dynamics. While chewing has been found to improve aspects of attention, a cognitive function, research is limited on the relationship between chewing and other motor tasks.

The first aim of this research …

Evaluating Direct Filtration As An Alternative To Conventional Carbon-Based Advanced Treatment For Indirect Potable Reuse, Savannah M. Flemmer

Civil & Environmental Engineering Theses & Dissertations

Hampton Roads Sanitation District (HRSD) is recharging purified wastewater into the Potomac Aquifer via the Sustainable Water Initiative for Tomorrow (SWIFT) project. Conventional SWIFT treatment applies coagulation, flocculation, sedimentation, ozonation, biofiltration, granular activated carbon (GAC) adsorption, and ultraviolet disinfection to secondary effluent to produce water that meets drinking water standards for managed aquifer recharge. HRSD is considering implementing direct filtration as an alternative to conventional treatment for two additional SWIFT facilities. Direct filtration presents an opportunity for significant cost savings by eliminating sedimentation, shortening flocculation detention time, and reducing coagulant usage. Without upstream removal of solids and organics, however, biofilters …

Nitrogen Cycling In The Lower Chesapeake Bay And Mid- And South Atlantic Bight, Yifan Zhu

OES Theses and Dissertations

Nitrogen (N) is central to marine primary production; its availability often limits the capacity and rates of primary productivity in most of the world’s oceans. Contrastingly, estuaries frequently receive anthropogenic N loading, oftentimes resulting in eutrophication, harmful algal blooms (HABs), and substantially degraded water quality. Nutrient variability in both estuaries and oceanic regimes results from meteorological forcing and physical processes, including wind-induced, tidal, and mesoscale mixing and upwelling. In this dissertation, a comprehensive investigation of N variability and cycling and its links to physical-biogeochemical processes was conducted using time-series monitoring approaches, flux estimations, satellite imaging, biogeochemical measurements, and molecular analyses. …

The Impact Of Covid-19 Stressors, Racial Discrimination, And Racial Socialization On Family Functioning In Black Families, Regina L. Alexander

Psychology Theses & Dissertations

Marginalized communities, specifically Black Americans, have been disproportionately impacted by the COVID-19 pandemic which has resulted in more hospitalizations and deaths within this particular community. However, this disproportionate impact of COVID-19 is likely the result of ongoing health disparities related to a lack of access to adequate healthcare. In addition to health disparities specifically related to COVID-19, Black Americans have also experienced public displays of racial discrimination resulting from the systemic racism that has occurred for many years. It has been determined that stress spillover can impact relationship factors and this same spillover may be an important factor by which …

Career Pathways Program Annual Report For Ay 2022/23, Wie Yusuf

Career Pathways

Career Pathways launched in August 2017 as the university-wide initiative to provide graduate student professional development. It encompasses both the Preparing Future Faculty (PFF) and the Preparing Future Professionals (PFP) Certificates. The Preparing Future Faculty Certificate was established in 2007, while the Preparing Future Professionals Certificate was launched in 2017 concurrently with Career Pathways. The Career Pathways program prepares graduate students for successful transition into thriving careers. With the PFP Certificate, specifically, the emphasize has been on filling the existing gap in career and professional development for master’s students and doctoral students with career plans outside of academia. Career Pathways …

A Dynamical Systems Approach To Characterizing Brain–Body Interactions During Movement: Challenges, Interpretations, And Recommendations, Derek C. Monroe, Nathaniel T. Berry, Peter C. Fino, Christopher K. Rhea

Rehabilitation Sciences Faculty Publications

Brain–body interactions (BBIs) have been the focus of intense scrutiny since the inception of the scientific method, playing a foundational role in the earliest debates over the philosophy of science. Contemporary investigations of BBIs to elucidate the neural principles of motor control have benefited from advances in neuroimaging, device engineering, and signal processing. However, these studies generally suffer from two major limitations. First, they rely on interpretations of ‘brain’ activity that are behavioral in nature, rather than neuroanatomical or biophysical. Second, they employ methodological approaches that are inconsistent with a dynamical systems approach to neuromotor control. These limitations represent a …

Comparison Between The Effects Of Acute Physical And Psychosocial Stress On Feedback-Based Learning, Xiao Yang, Brittany Nackley, Bruce H. Friedman

Psychology Faculty Publications

Stress modulates feedback-based learning, a process that has been implicated in declining mental function in aging and mental disorders. While acute physical and psychosocial stressors have been used interchangeably in studies on feedback-based learning, the two types of stressors involve distinct physiological and psychological processes. Whether the two types of stressors differentially influence feedback processing remains unclear. The present study compared the effects of physical and psychosocial stressors on feedback-based learning. Ninety-six subjects (Mage = 19.11 years; 50 female) completed either a cold pressor task (CPT) or mental arithmetic task (MAT), as the physical or psychosocial stressor, while electrocardiography and …

Control Of The Electroporation Efficiency Of Nanosecond Pulses By Swinging The Electric Field Vector Direction, Vitalii Kim, Iurii Semenov, Allen S. Kiester, Mark A. Keppler, Bennett L. Ibey, Joel N. Bixler, Ruben M. L. Colunga Biancatelli, Andrei G. Pakhomov

Bioelectrics Publications

Reversing the pulse polarity, i.e., changing the electric field direction by 180°, inhibits electroporation and electrostimulation by nanosecond electric pulses (nsEPs). This feature, known as “bipolar cancellation,” enables selective remote targeting with nsEPs and reduces the neuromuscular side effects of ablation therapies. We analyzed the biophysical mechanisms and measured how cancellation weakens and is replaced by facilitation when nsEPs are applied from different directions at angles from 0 to 180°. Monolayers of endothelial cells were electroporated by a train of five pulses (600 ns) or five paired pulses (600 + 600 ns) applied at 1 Hz or 833 kHz. Reversing …

Metals And Metal Complexes In Diseases With A Focus On Covid-19: Facts And Opinions, Agnieszka Ścibior, Manuel Aureliano, Alvin A. Holder, Juan Llopis

Chemistry & Biochemistry Faculty Publications

In the present Special Issue on “Metals and Metal Complexes in Diseases with a Focus on COVID-19: Facts and Opinions”, an attempt has been made to include reports updating our knowledge of elements considered to be potential candidates for therapeutic applications and certain metal-containing species, which are extensively being examined towards their potential biomedical use due to their specific physicochemical properties. The Special Issue compiles data on the role of metals in COVID-19 and focuses on other illnesses and biological processes that affect metal metabolism. It consists of eight manuscripts, including five review articles and three original research papers (Figure …

Newer Surveillance Data Extends Our Understanding Of The Niche Of Rickettsia Montanensis (Rickettsiales: Rickettsiaceae) Infection Of The American Dog Tick (Acari: Ixodidae) In The United States, Catherine A. Lippi, Holly D. Gaff, Robyn M. Nadolny, Sadie J. Ryan

Biological Sciences Faculty Publications

Background: Understanding the geographic distribution of Rickettsia montanensis infections in Dermacentor variabilis is important for tick-borne disease management in the United States, as both a tick-borne agent of interest and a potential confounder in surveillance of other rickettsial diseases. Two previous studies modeled niche suitability for D. variabilis with and without R. montanensis, from 2002-2012, indicating that the D. variabilis niche overestimates the infected niche. This study updates these, adding data since 2012.

Methods: Newer surveillance and testing data were used to update Species Distribution Models (SDMs) of D. variabilis, and R. montanensis infected D. variabilis, in …

Providing Family Centered Care Within Pediatric Integrated Care Settings, Emily D. Bebber

Counseling & Human Services Theses & Dissertations

Parent engagement remains critical to pediatric care. Both pediatric medical and mental health care remains dependent upon parent/guardian engagement to support successful outcomes for children and adolescents. Efforts to enhance Family Centered Care (FCC) has been spotlighted within pediatric care since the 1950s and the inclusion of counselors within integrated behavior health (IBH) teams ushers a need for an evolved understanding of the implementation of FCC, including parent/guardian engagement across professional roles. Using an explanatory mixed-method design, I examined team implementation of Family Centered Care (FCC) among different provider types (e.g., physicians, nurses, licensed mental health providers, social workers, technicians) …

Factors Influencing African American Women To Attend A Rural Community College And Persist To An Associate Degree, Lorraine Anita Justice

Educational Leadership & Workforce Development Theses & Dissertations

African American women utilize the community college environments as an avenue to attain an education and eventually pursue career and educational goals while remaining in their own communities. However, not much is known about the unique perceptions and experiences of African American women impacting their enrollment and persistence at rural community colleges. The purpose of this qualitative, descriptive research study was to examine the reasons African American female students choose to enroll and attend a rural community college to further their education and persist towards graduation with an Associate degree.

The data were collected using semi-structure individual interviews. Twelve African …

Landscape Genetics Of The Gulf Coast Tick, Amblyomma Maculatum, Sara Simmons Benham

Biological Sciences Theses & Dissertations

Connectivity among populations helps to maintain genetic diversity, population stability, and resilience. The Gulf Coast tick, Amblyomma maculatum, is a vector of the pathogen Rickettsia parkeri. Persistence of tick populations with high rates of R. parkeri infection poses health risks to humans and animals. Mitochondrial haplotypes were characterized by sequencing a fragment of the mitochondrial 16S rRNA gene. A comparative study of A. maculatum and Amblyomma americanum was conducted to identify similar and unique patterns between the species within the same region. Next, I compared A. maculatum sites across three different regions of the United States. This work …

E-Cadherin Force Transmission And Stiffness Sensing, Mazen Mezher

Mechanical & Aerospace Engineering Theses & Dissertations

E-cadherin is the chief mediator of cell-cell adhesion between epithelial cells and is a known mechanosensor. Force transmission and stiffness sensing are two crucial aspects of E-cadherin mechanobiology.

E-cadherin has an extracellular adhesive region, a transmembrane region and an intracellular region that binds to adhesion-associated proteins. Here, we assessed how different factors affect the level of force transmission (i) from inside the cell such as adhesion-associated proteins, (ii) on the cell membrane, such as growth factor receptors and (iii) outside the cell, such as different binding partners in adhesion. To study the level of force transmission inside the cell, we …

The Influence Of Mentorship On K-5 General Education Teachers: A Study Of Southeastern Schools In Virginia, Katherine Ryan Goldburg

Teaching & Learning Theses & Dissertations

The current teacher shortage and the demand for high quality teachers presents a nationwide educational problem. Additionally, more than one-third of teachers leave the profession within the first five years of their careers (Callahan, 2015). The most vital and systemic change that is needed in our educational landscape is the attraction, retention, and professional development of quality teachers (Darling-Hammond & Sykes, 2003). If school district administrators expect new teachers to succeed, they need to provide them with unprecedented levels of support. This qualitative research study examined new elementary education teachers' perceptions of the influence of their mentorship program and the …

An Autoethnography On Teaching Antiracism In The Current Sociopolitical Environment, Taylor M. Jacobson

Teaching & Learning Theses & Dissertations

In the course of American history, students from historically marginalized and underrepresented communities have been left out of the educational conversation. This has created an era of undereducated citizens who have historically used privilege to oppress students from these communities. Teachers must use their privilege to teach antiracist education that specifically encourages students to stand up for the justice needed to make a better world. Although this education is important, politicians, parents, and school board administrators are consistently putting teachers in an awkward position when they work towards implementing antiracist education by enacting policies that force them to stop or …

Cardiac Ablation And Stimulation With Nanosecond Pulsed Electric Fields (Nspefs), Federica Serra

Biomedical Engineering Theses & Dissertations

Surgical ablation of cardiac tissue is the definitive treatment for the most common arrhythmia, atrial fibrillation. In current medical practice, myocardial tissue is often ablated by the application of radiofrequency (RF) currents which are delivered through an electrode to create lesions that block the electrical pathways that sustain reentrant arrhythmias and restore the normal heart rhythm. An alternative to RF is cryoablation, during which the endocardial or epicardial tissue is brought in contact with a cryoprobe. Both RF ablation and cryoablation have significant limitations. In RF ablation, tissue is heated in order to ablate it, but it is an open …

Refinement Of Saliva Microrna Biomarkers For Sports-Related Concussion, Steven D. Hicks, Cayce Onks, Raymond Y. Kim, Kevin J. Kim, Kevin J. Zhen, Jayson Loeffert, Andrea C. Loeffert, Robert P. Olympia, Gregory Fedorchak, Samantha Devita, Zofia Gagnon, Callan Mcloughlin, Miguel M. Madeira, Scott L. Zuckerman, Timothy Lee, Matthew Heller, Chuck Monteith, Thomas R. Campbell, Christopher Neville, Elise Fengler, Michael N. Dretsch

Rehabilitation Sciences Faculty Publications

Purpose

Recognizing sport-related concussion (SRC) is challenging and relies heavily on subjective symptom reports. An objective, biological marker could improve recognition and understanding of SRC. There is emerging evidence that salivary micro-ribonucleic acids (miRNAs) may serve as biomarkers of concussion; however, it remains unclear whether concussion-related miRNAs are impacted by exercise. We sought to determine whether 40 miRNAs previously implicated in concussion pathophysiology were affected by participation in a variety of contact and non-contact sports. Our goal was to refine a miRNA-based tool capable of identifying athletes with SRC without the confounding effects of exercise.

Methods

This case-control study harmonized …

Opensim-Based Musculoskeletal Modeling: Foundation For Interactive Obstetric Simulator, Bahador Dodge

Electrical & Computer Engineering Theses & Dissertations

The use of mathematical and computational models to understand complex biological systems, such as the human birth process, is a rapidly growing field in medicine. These models can be used to optimize and personalize medical treatments for individual patients, enhance training, and aid in educational efforts. While recent advancements in healthcare, particularly in obstetrics, have improved care for mothers and babies, studies and government reports indicate a rising rate of maternal mortality in the United States.

Despite this rising trend, there is a lack of detailed studies concerning the use of modeling and simulation to develop an interactive obstetrics simulator …

Evaluating The Potential Use Of Saltwater Quarries In The Florida Keys For The Semi-Wild Mariculture Of Caribbean King Crab (Maguimithrax Spinosissimus), Samantha Glover

Biological Sciences Theses & Dissertations

Coral reef degradation, resulting from anthropogenic factors and natural change, has resulted in drastically reduced coral cover causing a phase shift from coral-dominated to macroalgae-dominated reefs, especially in the Caribbean. An important contributor to this shift is the loss of herbivores due to overfishing and the disease-related reduction of the long-spined sea urchin (Diadema antillarum) population during the 1980s. However, recent studies conducted in the Florida Keys have shown that increasing the abundance of herbivorous, native Caribbean king crabs (Maguimithrax spinosissimus) on reefs, can reduce the cover of nuisance algae and improve coral recruitment. Maguimithrax spinosissimus …