Digital Commons Network^™

Glucocorticoid Receptor Dysregulation Underlies 5-Ht2a Receptor-Dependent Synaptic And Behavioral Deficits In A Mouse Neurodevelopmental Disorder Model, Justin M. Saunders

Theses and Dissertations

Schizophrenia is a severe neuropsychiatric disorder that presents with diverse symptoms, some of which remain resistant to treatment. Increased risk of neurodevelopmental disorders such as schizophrenia has been observed following gestational infection in humans, leading to development of maternal immune activation (MIA) animal models. Increased density of the serotonin 5-HT2AR receptor (5-HT2AR), the primary target of hallucinogenic drugs and a key target of atypical antipsychotics, has been observed in postmortem antipsychotic-free prefrontal cortex samples from schizophrenia subjects, a change reflected in frontal cortex of adult MIA offspring. To model MIA, we administered 20 mg/kg i.p. of the viral mimetic poly-(I:C) …

Preference-Aware Task Assignment In Mobile Crowdsensing, Fatih Yucel

Theses and Dissertations

Mobile crowdsensing (MCS) is an emerging form of crowdsourcing, which facilitates the sensing data collection with the help of mobile participants (workers). A central problem in MCS is the assignment of sensing tasks to workers. Existing work in the field mostly seek a system-level optimization of task assignments (e.g., maximize the number of completed tasks, minimize the total distance traveled by workers) without considering individual preferences of task requesters and workers. However, users may be reluctant to participate in MCS campaigns that disregard their preferences. In this dissertation, we argue that user preferences should be a primary concern in the …

Feeling The Squeeze: The Association Between Multigeneration Caregiving And Informal Caregivers’ Health, Christine L. Patterson

Theses and Dissertations

While U.S. public policy and research has focused on the health needs of the aging population, less attention has been given to the consequences informal caregivers face caring for this generation. With the segment of the population aged 65 years or older growing rapidly, it is important to understand the factors that place informal caregivers at risk for poor health outcomes and health behaviors. Since multigeneration caregivers balance more personal, work, and caregiving demands than single-generation informal caregivers of older adults, they may be at higher risk for poor health outcomes. The aim of this study was to examine the …

K-Nearest Neighbors Density-Based Clustering, Avory C. Bryant

Theses and Dissertations

Traditional density-based clustering approaches rely on a distance-based parameter to define data connectivity and density. However, an appropriate value of this parameter can be difficult to determine as it is highly dependent on the underlying distribution of the data. In particular, distribution parameters affect the scale of inter-group distances (e.g., variance); this dependence leads to a well-known inability to simultaneously detect clusters at varying levels of density. In this work, connectivity and density are defined according to the rank-order induced by the distance metric (i.e., invariant to the expected scale of the distances). Connectivity by k-nearest neighbors and density by …

Applied Machine Learning In Extrusion-Based Bioprinting, Shuyu Tian

Theses and Dissertations

Optimization of extrusion-based bioprinting (EBB) parameters have been systematically conducted through experimentation. However, the process is time and resource-intensive and not easily translatable across different laboratories. A machine learning (ML) approach to EBB parameter optimization can accelerate this process for laboratories across the field through training using data collected from published literature. In this work, regression-based and classification-based ML models were investigated for their abilities to predict printing outcomes of cell viability and filament diameter for cell-containing alginate and gelatin composite hydrogels. Regression-based models were investigated for their ability to predict suitable extrusion pressure given desired cell viability when keeping …

Comparing The Sensitivity And Specificity Of Cbct And Mri In Detecting Osteoarthritis Of The Tmj: A Systematic Review, Gabriel R. Saavedra

Theses and Dissertations

The aim of this systematic review was to compare the sensitivity and specificity of cone-beam computed tomography (CBCT) and magnetic resonance imaging (MRI) in detecting osteoarthritis (OA) of the temporomandibular joint (TMJ). This was done by using computed tomography (CT) and the research diagnostic criteria for temporomandibular disorders (RDC/TMD) as reference methods and using CBCT and MRI as index methods. A specific search strategy was developed and applied to these electronic databases: PubMed, Embase, DOSS, and Cochrane. The search results returned 802 articles, which were then narrowed down using the inclusion/exclusion criteria, to four final articles that were included in …

Amixicile, A Novel Antimicrobial Agent, And Its Effect On The Salivary And Subgingival Microbiome In Rhesus Macaque Monkeys, Erin E. Block

Theses and Dissertations

Background/Purpose: Periodontitis is an inflammatory disease with a bacterial etiology in a susceptible host. A selective antibiotic with minimal systemic side effects could be a useful adjunct to traditional periodontal therapy. Amixicile is a novel antimicrobial agent that targets pyruvate: ferredoxin oxidoreductase (PFOR), an enzyme that is critical for anaerobic bacterial metabolism and has been found to have little-to-no side-effects in animal models. The aim of this study was to prospectively evaluate the effect of amixicile on clinical periodontal parameters and the composition of the oral microbiome in rhesus macaque monkeys. It was hypothesized that the amixicile would reduce growth …

Antibiotic-Loaded Dendrimer Hydrogels In Periodontal Bone Regeneration: A Feasibility Study, Nicholas G. Yesbeck

Theses and Dissertations

Purpose: Prescription of a complete course of oral antibiotics following bone grafting procedures is a common clinical practice in surgical periodontics. Prophylactic administration of antibiotics reduces the risk of surgical site infection and systemic administration is preferred over local delivery because of short duration of action in the latter circumstance. The goal of this study is to demonstrate the ability of dendrimer hydrogels (DH) to prolong the release kinetics of antibiotics in-vitro. A secondary goal will be to analyze the effect of different particulate bone allografts on the release kinetics of the antibiotic.

Methods: Dendrimer hydrogels (DH) were synthesized …

Stat5a Regulation By Serine Phosphorylation In Breast Cancer, Alicia E. Woock

Theses and Dissertations

The neuroendocrine hormone prolactin (PRL) and its cognate receptor (PRLr) have been implicated in the pathogenesis of breast cancer. PRL signaling relies on activating kinases such as the tyrosine kinase Jak2 and serine/threonine kinases ERK1/2, NEK3, PI3K, and AKT. In the canonical pathway of PRL signaling, JAK2 phosphorylates the transcription factor STAT5a at tyrosine residue 694 (pY694-STAT5a), preceding STAT5a nuclear translocation and transcriptional activity. However, STAT5a exists with functional duality as a transcription factor, having both pro-differentiative and pro-proliferative target genes. Other STAT family members (STATs 1, 3, and 6) have been shown to have transcriptional activity in the un-tyrosine-phosphorylated …

Fabrication Of Metal-Silicon Nanostructures By Reactive Laser Ablation In Liquid, Eric J. Broadhead

Theses and Dissertations

Metal-silicon nanostructures are a growing area of research due to their applications in multiple fields such as biosensing and catalysis. In addition, silicon can provide strong support effects to metal nanoparticles while being more cost effective than traditionally used supports, like titania. Traditional wet-chemical methods are capable of synthesizing metal-silicon nanostructures with a variety of composition and nanoparticle shapes, but they often require high temperatures, toxic solvents, strong reducing agents, or need capping agents added to stabilize the nanoparticles. Laser processing is an emerging technique capable of synthesizing metal-silicon composite surfaces that offers a faster, simpler, and greener synthesis route …

Evaluation Of Cell Lysis Techniques For Direct Amplification Of Sexual Assault Samples, Sarah Schellhammer

Theses and Dissertations

Sexual assault is one of the most common crimes committed today with a delay in sample processing, resulting in the “rape kit backlog”. The traditional method to extract DNA from these samples containing both male and female DNA is a differential extraction; taking hours to process. This study examined a variety of different cell lysis techniques to develop a method which can consistently generate high-quality profiles at a fast rate and with low volumes when compared to the currently used method in our laboratory.

Six lysis methods, in addition to the currently used forensicGEM™ Sperm kit, were performed on …

The Impact Of Latent Print Processing On Firing Pin And Breechface Impressions During Firearm Examination, Brittany B. Harrington

Theses and Dissertations

Latent prints can be a valuable source of forensic evidence when solving a crime. They can verify if a person was at a specific scene, identify unknown individuals to connect them to a scene, and help to corroborate eyewitness accounts. Latent prints, however, are not always visible until they have undergone enhancement or visualization techniques. When fired cartridge cases are suspected of containing latent prints, they are brought in for latent print processing before any firearm analysis is performed. As a result, these cartridges are often coated in various residues or dyes when they arrive for firearm examination. In response, …

Creation And Optimization Of An Optical Trapping Microfluidic Device For The Separation Of Mock Forensic Sexual Assault Samples, Mackenzie Lally

Theses and Dissertations

Cell mixtures are often seen in forensic samples and commonly involve sexual assault cases where mixtures of sperm cells and vaginal epithelial cells are frequently encountered. This produces challenges in downstream analysis in the form of STR mixture profiles. The only method currently in use in crime laboratories for front-end sperm and epithelial cell separation is differential extraction. This method often results in STR mixture profiles due to carryover into both the male and female fractions and suffers from a wide range of efficiency depending on the laboratory or individual processing the sample. Optical trapping offers an alternative method for …

The Efficacy Of Recovering Latent Fingerprints From Fired Cartridge Cases By Way Of Cyanoacrylate Fuming Combined With Basic Yellow Dye Staining, Lily Mantz

Theses and Dissertations

This experiment attempted to tackle the long-standing struggle to consistently recover latent fingerprints from fired cartridges. With an emphasis on realistic handling of high volume of samples combined with Cyanoacrylate fuming followed by Basic Yellow dye staining, a total of 740 cartridges were examined. These included fired and unfired brass and nickel case 9mm Luger and 40 S&W cartridges. The cartridges were divided into five different groups; each were treated differently prior to cyanoacrylate fuming and dye staining, which was conducted in the same manner for the groups. The groups included the positive and negative controls, loaded, cycled, and fired. …

Qualitative And Quantitative Characterization Of Epithelial Cell Mixtures Using Hormone Antibody Probes And Flow Cytometry, Luke Baldridge

Theses and Dissertations

“Touch” DNA is evidence that consists of epidermal cells deposited by handling objects and it is becoming more common in evidence samples processed in crime labs. Because “touch” DNA evidence samples may be low-template DNA and are often mixtures, there is a need to both nondestructively estimate the amount of DNA present prior to DNA purification and to identify and characterize mixtures prior to DNA typing. The purpose of this study was to test the use of FITC-labeled anti-testosterone antibodies as a potential tool to estimate the number of contributors in two-, three-, and four-person mixtures of epidermal skin cells, …

Powerplex® Fusion 6c System Versus Powerplex® Fusion 5c: A Comparison Of Performance Metrics, Caitlin M. Mccaughan

Theses and Dissertations

Following the FBI mandated expansion of the CODIS core loci from 13 to 20, several manufacturers developed short tandem repeat (STR) typing kits in response to the new criteria. One such manufacturer was the Promega Corporation, which released the PowerPlex® Fusion 5C megaplex STR typing kit (Fusion 5C) in 2012. Currently, the Virginia Department of Forensic Science (VDFS) utilizes this amplification kit for both casework and database applications. In 2015, Promega released the PowerPlex® Fusion 6C STR typing kit (Fusion 6C), which contains three additional loci beyond those included in PowerPlex® Fusion 5C, and a sixth color channel. The power …

Evaluation Of Dna Extraction Efficiencies Of Promega’S Dna Iq™ Methods And Casework Extraction Kit For Low Template Samples, Emily M. Anderson

Theses and Dissertations

Biological evidence from crime scene samples frequently contain low levels of DNA, such as the most predominant form of evidence, which is DNA deposited by handling objects or “touch evidence”. To maximize the DNA yield recovered from theses challenging samples, forensic laboratories must optimize the extraction methods utilized to isolate and purify DNA for downstream short tandem repeat (STR) amplifications. Currently, the Virginia Department of Forensic Science (VADFS) uses a DNA IQ™ System (DNA IQ) extraction method for isolation of DNA from most forensic samples. This extraction procedure, which combines DNA IQ™ lysis buffer and Dithiothreitol (DTT), has been validated …

Quantitative Pcr And Sanger Sequencing Of Mitochondrial Dna Recovered From Waterlogged Bone, Kailey Babcock

Theses and Dissertations

In forensic contexts, samples containing heavily fragmented DNA are commonly encountered. Compromised biological samples are especially prevalent in instances where human remains have been submerged in an aqueous environment for extended periods of time. Nuclear DNA is particularly vulnerable to the prolonged exposure to heat, moisture, and bacterial degradation that are prevalent in aquatic settings. Paired with the difficulty of recovering DNA from skeletal remains, which are often the only remaining component after the soft tissues have been stripped away, mitochondrial DNA (mtDNA) analysis serves as an invaluable alternative. In this multifaceted study, mtDNA analysis was performed on waterlogged bone …

Development Of An Analytical Method And Sample Preparation Technique For The Analysis Of Sulfur-Containing Fentanyl Analogs By Uplcmsms, And The Application To Forensic Science, Amber D. Budmark

Theses and Dissertations

In February 2018, the US DEA Agency released a statement of the emergency scheduling (Schedule 1) of all fentanyl analogs not already regulated by the CSA due to an alarming increase in overdose deaths linked to synthetic opioids. Fentanyl analogs are pharmacologically similar to fentanyl, but often more potent. This increased potency can create problems with proper dosing of fentanyl analogs leading to untoward effects including an increase in overdoses and deaths. Since 2018, there has been a 38.4% increase in illicitly manufactured fentanyl overdose deaths leading the CDC to make available the FAS Kit and Emergent Panels containing previously …

Detection Of 2,4,6-Trinitrotoluene Using A Colorimetric Gold Nanoparticle Air Cassette Filter, Andrea I. Ferrer Vega

Theses and Dissertations

Trinitrotoluene (TNT) is an explosive commonly used during military and terrorist activities. Current methods to identify this compound require sampling, transport and analysis at a forensic lab using analytical instrumentation. However, on-site detection is needed to assist efforts to prevent detonation. Gold nanoparticles have been used as sensors throughout the years due to their versatility and surface enhanced Raman scattering properties in the presence of an analyte and low limits of detection. By taking advantage of the Meisenheimer complex that TNT forms in the presence of amines, it is possible to determine its presence at picogram levels. Subsequently, adhering amine …

Comparison Of Semi-Automated And Manual Differential Separation Methods For Mock Sexual Assault Samples, Stephanie Rink

Theses and Dissertations

In the event of a sexual assault, separation of suspect from victim DNA is possible through differential extraction if the evidentiary mixture consists of female epithelial cells and male spermatozoa. The basis of differential extraction is the differing properties of epithelial and sperm cell membranes, specifically the comparative sturdiness of the proteins making up the sperm head containing the male DNA. Effective retrieval and separation of male and female DNA fractions is important in generating high-quality STR profiles that can be utilized in identifying suspects in a sexual assault case. Differential extraction has been conventionally performed using Proteinase K (PK) …

Evaluation Of Five Methods To Develop Latent Prints On Thermal Paper, Jenna Pregent

Theses and Dissertations

Forensic latent fingerprint laboratories determine the proper techniques for fingerprint visualization based on the substrates upon which they are deposited. Typical forensic analysis of thermal paper evidence involves the application of ninhydrin and/or 1,2-indanedione dissolved in a polar solvent. However, polar solvents create an undesirable reaction with the thermal paper’s internal properties and often lead to discoloration of the evidence. When this occurs, not only are the fingerprints less likely to be visible due to the loss of contrast, but the evidentiary print on the receipt may be lost entirely. This research sought to compare five development methods to determine …

Art Museum Docent Coordinators’ Perceptions: A Difficult Kind Of Balancing Act, Jennifer E. Schero

Theses and Dissertations

With visitors numbering in the millions, museums provide numerous entry points for attendees to engage with the objects in their care, including offering tours of their collections. Looking specifically at art museums, many institutions utilize volunteers to facilitate these guided looking experiences. Considerable research within the field of museum education focuses on the qualities of effective touring and methods and theories to support these endeavors. However, there is a lack of research focusing on the docent coordinators who oversee these volunteer guides. This study utilizes interpretive phenomenological analysis to explore perceptions of encyclopedic art museum docent coordinators concerning their preparation …

Gender Equity Implications Of Nonprofit Youth Programs: Education Outcomes Of Three African American-Led Nonprofits, Yali Pang

Theses and Dissertations

Significant racial and gender differences in school performance have been a great concern in the past decades, and especially the significant differences in education performance between both Black youth and other racial groups and between Black males and Black females. Nonprofit youth programs are increasingly considered a promising intervention that can effectively improve Black youth development and education outcomes. While there is a growing body of literature evaluating the outcomes of nonprofit youth programs, little is known about gender differences in the outcomes, and specifically whether these nonprofit programs are equally effective for both Black males and females. This study …

Development And Evaluation Of A Combinatorial Rt-Qpcr Multiplex For Forensic Body Fluid Identification, Carolyn A. Lewis

Theses and Dissertations

Body fluid identification is essential in the forensic biology workflow that assists DNA analysts in determining where to collect DNA evidence. Current presumptive tests lack the sensitivity and specificity molecular techniques can achieve; therefore, molecular methods, such as microRNA and microbial signatures, have been extensively researched in the forensic community. Limitations of each method suggest combining molecular markers to increase discrimination efficiency of multiple body fluids from a single assay. While microbial signatures have been successful in identifying fluids with high bacterial abundances, microRNAs have shown promise in fluids with low microbial abundance. A disadvantage of RNA analysis in forensic …

Microrna In The Mammalian Growth Plate: Matrix Vesicles And 1Α,25-Dihydroxyvitamin D3, Niels C. Asmussen

Theses and Dissertations

Growth plate chondrocytes are the driving force of long bone elongation and they accomplish this vital task, in part, by producing, remodeling, and finally mineralizing the cartilage tissue that makes up the growth plate. This mineralized tissue is turned over again as bone forming cells invade and began the process of turning mineralized cartilage into bone. Chondrocytes undergo a distinct series of observable phases as they move through this process transitioning from a stage of proliferation to one of hypertrophy and finally capillary invasion. Chondrocytes produce matrix vesicles (MVs) that they release into the growth plate and that attach to …

Water Clarity At The River-Estuary Transition Zone: A Comparative Study Of The James, Mattaponi, And Pamunkey Sub-Estuaries, Rachel Henderson

Theses and Dissertations

Water clarity is a key parameter for monitoring water quality and often used to assess habitat suitability for submerged aquatic vegetation (SAV). Light attenuation, a measure of water clarity, is impacted by colored dissolved organic matter (CDOM), and by suspended particulates which include living and non-living components. We anticipated that the relative importance of these factors in regulating light attenuation would vary among the upper portions of three sub-estuaries differing in morphometry, hydrology, and degree of human influence. The James is characterized by eutrophic conditions and high algal abundance, whereas the Mattaponi and Pamunkey exhibit lower phytoplankton production. The Mattaponi …

Leading In Crooked Rooms: Race, Gender, Culture And Black Women's Leadership Skills And Practices, Portia Newman

Theses and Dissertations

The literature on Black women leaders, where it exists, focuses on the barriers to Black women becoming leaders or being fully empowered when in leadership positions. However, to understand the leadership identity of Black women, and perhaps help to explain the absence of Black women in formal leadership spaces, means to examine the influence of race, gender, and culture on leadership behavior, as well as the setting in which leadership exists. This qualitative grounded theory study explored the leadership skills and practices of 15 senior-level cross sector Black women leaders. The data was collected in two phases: 1) a leadership …

An Exploration Of Teacher Residents’ Perception Of Culture And Their Use Of Culturally Responsive Pedagogy, Jodi Larson

Theses and Dissertations

Urban teacher residency (UTR) programs place residents in urban schools labeled “hard-to-staff” or “under-resourced.” Enrollment in residency schools tends to be majority Brown or Black students from various cultures. Teacher residents are from diverse backgrounds and races who have a commitment to teach in Title 1 schools with the support of a residency program that coaches them how to teach using culturally relevant pedagogy. Their journeys are unique from typical student teaching experiences because they co-teach with an experienced teacher for a full school year while attending university classes on pedagogy and theory. This qualitative case study followed seven elementary …

Influence Of Metal Sleeves In The Accuracy Of Dental Implant Placement Using Guided Implant Surgery, Coleman Adams

Theses and Dissertations

The fabrication of implant surgical guides through stereolithographic 3D printing has become a staple in dental implant guided surgery over the last couple decades. These surgical guides have typically utilized metal sleeves to assist in guidance of the drills during osteotome preparation. The metal sleeves can be costly and potentially cause deviations if improperly placed during post-processing of the guide. This research explored a novel method for the utilization of sleeve-free surgical guides by comparing the dimensional and angulational deviations between the implant guides with and without a metal sleeve. To achieve this goal, two separate aims were pursued. Our …