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Multiferroic Nanomagnetic Logic: Hybrid Spintronics-Straintronic Paradigm For Ultra-Low Energy Computing, Mohammad Salehi Fashami

Theses and Dissertations

Excessive energy dissipation in CMOS devices during switching is the primary threat to continued downscaling of computing devices in accordance with Moore’s law. In the quest for alternatives to traditional transistor based electronics, nanomagnet-based computing [1, 2] is emerging as an attractive alternative since: (i) nanomagnets are intrinsically more energy-efficient than transistors due to the correlated switching of spins [3], and (ii) unlike transistors, magnets have no leakage and hence have no standby power dissipation. However, large energy dissipation in the clocking circuit appears to be a barrier to the realization of ultra low power logic devices with such nanomagnets. …

The Impact Of A Primary Care Psychology Training Program On Medical Utilization In A Community Sample, Autumn Lanoye

Theses and Dissertations

Mental illness and psychological distress is associated with higher rates of medical service usage and treatment of these issues results in more appropriate medical utilization rates. Little research has been conducted in an integrated care clinic, wherein health psychologists or behavioral health specialists work together with physicians to provide patient care. The current study examines the effects of brief behavioral and mental health interventions on patient medical utilization in this setting with care delivered by medical residents and doctoral psychology trainees. Access to the health system’s electronic billing records allowed for objective measures of annual healthcare utilization in terms of …

Characterization Of The Effects Of Iron On Neisseria Gonorrhoeae Surface Protein Modulation And Host Cell Interactions, Aminat Oki

Theses and Dissertations

Iron is an essential nutrient that is sequestered by iron-binding proteins in the human host resulting in a hostile environment for microbes. Neisseria gonorrhoeae, however, can utilize numerous iron-binding proteins such as transferrin and lactoferrin to acquire this nutrient. During initial infection, gonococci have access to transferrin and lactoferrin present in semen and vaginal fluids, as well as to hemoglobin present in blood during menses or disseminated infections. Consequently, the gonococcus likely encounters conditions of high iron at some stages in the course of natural infection. Potential contributions of iron to gonococcal invasion have however been largely over looked in …

Evaluation Of The Allometric Exponents In Prediction Of Human Drug Clearance, Da Zhang

Theses and Dissertations

Background. Allometric scaling (AS) is widely used in predicting human clearance (CL) based on animal data. Substantial prediction errors have been commonly observed and various modifications to AS have not provided a broad reliable improvement. In this study, an extensive data set was assembled including animal and human systemic CL and physiochemical properties. The allometric exponents were calculated based on multiple species AS and single-species AS methods. The correlations between the allometic exponents and physiochemical properties were evaluated in an attempt to find covariates that may explain the inter-compound variability in the allometric exponents. Lastly, the statistical approaches in analyzing …

Computational Study Of Protein-Protein Interactions In Misfolded States, Oscar Bastidas

Theses and Dissertations

Protein-protein interactions (PPI’s) play important roles in biological systems. In particular, intra-protein interactions help create and maintain correctly folded protein states and mutations that result in misfolded states may be associated with significant changes in PPI behavior. Six unrelated protein systems with known structure files, each consisting of a wild-type and mutant strain, were studied using the computational algorithm OpenContact©. OpenContact© is a simple tool that can be used to rapidly identify or map interactions “hot-spots” in a protein and was, consequently, used in this study as a starting point to examine the potential or possible role of PPI’s on …

Prediction Of Human Systemic, Biologically Relevant Pharmacokinetic (Pk) Properties Using Quantitative Structure Pharmacokinetic Relationships (Qspkr) And Interspecies Pharmacokinetic Allometric Scaling (Pk-As) Approaches For Four Different Pharmacological Classes Of Compounds, Gopichand Gottipati

Theses and Dissertations

This research developed and validated QSPKR models for predicting in-vivo human, systemic biologically relevant PK properties (i.e., reflecting the disposition of the unbound drug) of four, preselected, pharmacological classes of drugs, namely, benzodiazepines (BZD), neuromuscular blocking agents (NMB), triptans (TRP) and class III antiarrhythmic agents (AAR), as well as PK allometric scaling (PK-AS) models for BZD and NMB, using pertinent human and animal systemic PK information (fu, CLtot, Vdss and fe) from published literature. Overall, lipophilicity (logD7.4) and molecular weight (MW) were found to be the most important and statistically significant molecular properties, affecting biologically relevant systemic PK properties, and …

The Role Of Toll-Like Receptor 9 In Periodontitis, Paul Kim

Theses and Dissertations

Periodontitis is a biofilm-initiated inflammatory disease, resulting in soft tissue damage and alveolar bone loss. A nucleic acid sensor, toll-like receptor 9 (TLR9), has been recently implicated in periodontal inflammation. This study utilized an in vivo periodontitis model using TLR9 knockout (TLR9-/-) mice to assess the role of TLR9 in periodontitis. Significant bone loss was observed in wild type, but not in TLR9-/- mice. Further experiments using ex vivo assays revealed significantly higher IL-6 production in splenocytes of wild type mice compared to knockout cells in response to Porphyromonas gingivalis (a keystone pathogen for periodontitis) challenge. In conclusion, TLR9 contributes …

Transitioning From A Traditional Nursing Home Environment To Green House Homes: What Are Stakeholders' Attitudes Toward And Satisfaction With The Small House Care Environment, Christine Harrop-Stein

Theses and Dissertations

This dissertation research was designed as two independent research studies. The first study, qualitative, and non-experimental, aimed to examine residents’, family members’, and staff members’ (stakeholders’) satisfaction with, and attitudes toward Green House living one month prior to moving and again at one and three months after moving. Focus groups were the primary method of data collection. Thirty residents and 40 staff members transitioned to one of three Green House homes beginning January, 2013. Data collected began in December, 2012. Following each focus group, tape recordings were transcribed, and coded. Using grounded theory and the constant comparative method of analysis, …

Long-Term Outcomes Of Prolonged Exposure And Naltrexone For Patients With Comorbid Posttraumatic Stress Disorder And Alcohol Dependence, Shelley Avny

Theses and Dissertations

A growing body of research is examining effective treatment(s) for individuals with comorbid posttraumatic stress disorder (PTSD) and alcohol dependence (AD). However, treatments for this comorbid population have been inadequately studied in the longer term. This study represents a long-term follow-up assessment of a randomized controlled trial that compared combined therapy (prolonged exposure + naltrexone) with monotherapies (prolonged exposure or naltrexone) for patients with PTSD and AD (see Foa, Yusko, McLean et al., 2013). Attempts were made to contact 120 participants 5-10 years after the original trial to assess the maintenance of treatment gains. Nineteen individuals were located and agreed …

Reversed-Phase Ion-Pairing Ultra Performance Liquid Chromatography-Mass Spectrometry In Characterization Of Glycosaminoglycans, Alhumaidi Alabbas

Theses and Dissertations

Glycosaminoglycans (GAGs) are a family of linear bio-polysaccharides, which are heterogeneously modified with negatively charged sulfate and carboxylate groups. They are located on every cell surface, extracellular matrix or intracellular space in the body. GAGs are composed of alternating units of an amino sugars (glucosamine or galactosamine) and hexuronic acid/hexose (iduronic acid, glucoronic acid/ or galactose), which are linked by glycosidic bonds with different geometries. In recent years, GAGs have attracted considerable interest. GAGs play vital roles in fundamental biological processes, such as hemostasis, angiogenesis, cell signaling, growth and differentiation. Thus, GAGs contribute to a number of diseases such as …

Development Of Bivalent Ligands Targeting The Putative Ccr5-Mor Heterodimer, Thomas Raborg

Theses and Dissertations

Chemokine receptor CCR5 (CCR5) is a G-protein coupled receptor (GPCR) predominantly expressed on leukocytes, or white blood cells.1–3 During inflammation, the body releases chemokines that bind to receptors such as CCR5 and attract leukocytes to the area of inflammation, leading to an immunological response.1 CCR5 is also an important receptor in the human immunodeficiency virus's (HIV-1) invasion of host cells, as CCR5 acts as a co-receptor that facilitates HIV-1 viral entry.4,5 The continued destruction of leukocytes as a result of HIV-1 viral entry produces a disease state called acquired immunodeficiency syndrome (AIDS).5 Of note, this receptor is also expressed on …

A Route To Discover Small Molecule Inhibitors Of Psaa, A Potential Target For Streptococcus Pneumoniae, Ahmad J. Obaidullah

Theses and Dissertations

Due to the development of multidrug resistance in Streptococcus pneumoniae, research has begun to define new drug targets for pneumonia therapy. Different research groups have identified a lipoprotein, PsaA that is important for pneumonia virulence. PsaA is a manganese transporter that is required for bacterial virulence and growth. We have employed computer modeling to virtually screen a small-molecule database for inhibition of PsaA function by targeting the metal binding pocket, performing receptor-based virtual screening and molecular docking and scoring to identify potential inhibitors of PsaA function. We have developed an assay for screening compounds, including the use of a PsaA …

Therapeutic Efficacy Of Combination Of Mtor Inhibitors And Ampk Activators In Non-Small Cell Lung Cancer., Grinal Corriea

Theses and Dissertations

Pemetrexed (PTX), an antifolate drug, has been approved by the US FDA for first line therapy of mesothelioma and non-small cell lung cancer. In addition to its primary site of action on thymidylate synthase (TS), PTX also inhibits the second folate-dependent enzyme of purine biosynthesis aminoimidazolecarboxamide ribonucleotide formyltransferase (AICART). The accumulation of the substrate for AICART, ZMP, in PTX-inhibited cancer cells leads to activation of AMP-activated protein kinase (AMPK) with subsequent inhibition of mammalian target of rapamycin (mTOR) and hypophosphorylation of its downstream targets responsible for protein synthesis and cell proliferation. Inhibitors of mTORC1 like Rapamycin and its analogs (rapalogs) …

An Investigation Of Nurbs-Based Deformable Image Registration, Travis J. Jacobson

Theses and Dissertations

Deformable image registration (DIR) is an essential tool in medical image processing. It provides a means to combine image datasets, allowing for intra-subject, inter-subject, multi-modality, and multi-instance analysis, as well as motion detection and compensation. One of the most popular DIR algorithms models the displacement vector field (DVF) as B-splines, a sum of piecewise polynomials with coefficients that enable local shape control. B-splines have many advantageous properties in the context of DIR, but they often struggle to adequately model steep local gradients and discontinuities. This dissertation addresses that limitation by proposing the replacement of conventional B-splines with a generalized formulation …

An Automated Dental Caries Detection And Scoring System For Optic Images Of Tooth Occlusal Surface, Leila Ghaedi

Theses and Dissertations

Dental caries are one of the most prevalent chronic diseases. Worldwide 60 to 90 percent of school children and nearly 100 percent of adults experienced dental caries. The management of dental caries demands detection of carious lesions at early stages. The research of designing diagnostic tools in caries has been at peak for the last decade. This research aims to design an automated system to detect and score dental caries according to the International Caries Detection and Assessment System (ICDAS) guidelines using the optical images of the occlusal tooth surface. There have been numerous works that address the problem of …

Development Of A Compact, Low-Cost Wireless Device For Biopotential Acquisition, Graham Kelly

Theses and Dissertations

A low-cost circuit board design is presented, which in one embodiment is smaller than a credit card, for biopotential (EMG, ECG, or EEG) data acquisition, with a focus on EEG for brain-computer interface applications. The device combines signal conditioning, low-noise and high-resolution analog-to-digital conversion of biopotentials, user motion detection via accelerometer and gyroscope, user-programmable digital pre-processing, and data transmission via Bluetooth communications. The full development of the device to date is presented, spanning three embodiments. The device is presented both as a functional data acquisition system and as a template for further development based on its publicly-available schematics and computer-aided …

Comparison Of Two Different Sprint Interval Training Work-To-Rest Ratios On Acute Metabolic And Inflammatory Responses, Christopher R. Harnish

Theses and Dissertations

High intensity exercise is believed to yield greater results on health and human performance than moderate intensity exercise. Extensive research indicates that not only do high-intensity interval training (HIT) and sprint interval training (SIT) produce significant improvements in cardiovascular fitness and disease, they may be more effective at improving long-term metabolic function, including insulin sensitivity (Si), by producing more mitochondria. Moreover, compliance rates for HIT and SIT participation are reported to be the same or better than traditional moderate intensity exercise. Because lack of time is often cited as major hindrance to exercise participation, SIT is also seen as a …

Domestic Violence: Contemporary Interventions And The Rise Of Specialized Domestic Violence Units, Laura E. Anderson

Theses and Dissertations

This dissertation examines recidivism for domestic violence offenders under both traditional probation and specialized probation conditions. This research compares recidivism at a traditional probation locality (Riverside Criminal Justice Services) and a specialized domestic violence unit (Chesterfield Community Corrections Services) in order to determine the nature of recidivism at both localities. In addition, the research aims to identify individual risk factors which are statistically associated with recidivism. The research is based on secondary data and draws on offender criminal records generated by the Virginia State Police, as well the extraction of information from probation files at both localities. The multivariate models …

Novel 3d Head And Neck Cancer Model To Evaluate Chemotherapeutic Efficacy, Kelly Morgan

Theses and Dissertations

HNSCC accounts for 7 percent of all new cancer occurrences. Despite currently available treatments, there continues to be a high mortality and recurrence rate in HNSCC. Well over 50 percent of all cancer patients receive chemotherapy as a standard treatment. However, only 5 percent of these cases have been shown to help with treatment of the disease. Formerly, two options were available for drug testing: in vivo animal models, and in vitro two-dimensional models. While in vivo models remain the most representative, their use is burdened by high costs, time constraints, and ethical concerns. 2D models are simple to use …

Acquired Epigenetic And Chromosomal Changes In Women Treated For Breast Cancer, Noran Aboalela

Theses and Dissertations

Improved survival for women receiving chemotherapy for breast cancer (BC) has been accompanied by the development/persistence of psychoneurological symptoms (PNS) that compromise their quality of life. The biological basis for these PNS is unknown, but could reflect the acquisition of soma-wide chromosomal/epigenetic alterations. An important first step in testing this hypothesis is to determine if somatic genetic/epigenetic changes arise and persist following treatment. To answer this question we longitudinally studied 71 women (ages 23-71) with early-stage BC and collected measures before chemotherapy (baseline), and 4 weeks (mid-chemo); six months (during radiation therapy for a subset of women); and one year …

Group Home Care: The Influence Of Positive Youth Development Factors And Social Capital On Youth Outcomes, Sundonia J. Wonnum

Theses and Dissertations

This study examined the influence of positive youth development factors and social capital on outcomes among youth in group home care. One of the major assumptions of this study was that existing research is deficit-focused and provides little evidence of what practices are linked to positive outcomes among youth residing in and exiting group homes. A conceptual model was developed to depict the influence of predictors (derived from the Positive Youth Develop Framework and Social Capital Theory) on youth outcomes – change in psychosocial problem severity and prosocial behavior, living environment, school involvement, employment, delinquency, and extracurricular activity. An exploratory …

Food Landscapes: A Case Study Of A Cooking And Art- Focused Program For Teens Living In A Food Desert, Jessica R. Norris

Theses and Dissertations

This study constructs themes and propositions about the experiences of youth participants in the fall 2013 Food Landscapes program at the Neighborhood Resource Center in Richmond, Virginia. During the program, youth participated in cooking-based volunteerism with adults with disabilities and created short videos about their experiences. In this study, I analyzed pre- and post-program participant interviews, twice-weekly program observations, and facilitator reflections to understand how Food Landscapes affected youths’ conception of community engagement and communication strategies. This case study offers insight into how youth experience after-school programming of this design. Based on my findings, youth develop and rely upon a …

Seeing The Sausage Made: How Compromise Works In Large Groups And Representative Bodies, James E. Crawford Jr.

Theses and Dissertations

Inspired by the lack of Congressional compromise during the 2013 federal shutdown, I explore how compromise works in large groups and representative bodies. An on-line survey, personal interviews, and a discourse analysis of the Congressional Record yield a diverse collection of data, including personal and public stories of compromise. I examine the stories and other data through an eclectic mix of contemporary scholarship, borrowing literary theory from the Russian critic Mikhail Bakhtin, socio-linguistic concepts from American linguist James Paul Gee, and moral philosophy from Israeli thinker Avishai Margalit. I also incorporate the work of political scientists Amy Gutmann and Dennis …

Analysis Of The Role Of Astrocyte Elevated Gene-1 In Normal Liver Physiology And In The Onset And Progression Of Hepatocellular Carcinoma, Chadia L. Robertson

Theses and Dissertations

First identified over a decade ago, Astrocyte Elevated Gene-1 (AEG-1) has been studied extensively due to early reports of its overexpression in various cancer cell lines. Research groups all over the globe including our own have since identified AEG-1 overexpression in cancers of diverse lineages including cancers of the liver, colon, skin, prostate, breast, lung, esophagus, neurons and neuronal glia as compared to matched normal tissue. A comprehensive and convincing body of data currently points to AEG-1 as an essential component, critical to the progression and perhaps onset of cancer. AEG-1 is a potent activator of multiple pro-tumorigenic signal transduction …

Perceptions Of Acupuncture And Acupressure By Anesthesia Providers, Amanda Faircloth

Theses and Dissertations

BACKGROUND: Randomized controlled trials show acupuncture and acupressure support anesthesia management by decreasing anxiety, opioid requirements and treating post-operative nausea and vomiting. Acupuncture and acupressure have demonstrated clinical usefulness and received governmental support (NIH, PPACA, WHO, U.S. Military), but have not yet diffused into mainstream anesthesia practice. This study examined US anesthesia providers' perceptions of acupuncture and acupressure.

METHODS: Ninety-six anesthesiology departments stratified by geographic region (Northeast, South, West, and Midwest) and institution type (university medical centers, community hospitals, children’s hospitals, and VA hospitals) were selected for participation in an anonymous, online survey. The target sample was 1,728 providers …

Adaptive Radiation Therapy For Lung Cancer, Christian W. Dial

Theses and Dissertations

Prognosis for lung cancer patients remains poor. For those receiving radiation therapy, local control and survival have been shown to improve with increased doses; however, deliverable dose is often limited by associated toxicity. Therefore, methods that reduce dose to normal tissues and allow isotoxic escalation are desirable. Adaptive radiation therapy seeks to improve treatment by modifying the initial plan throughout delivery, and has been shown to decrease normal tissue dose. Studies to date suggest a trend of increasing benefit with increases in replanning frequency; however, replanning is costly in terms of workload and past studies implement at most weekly adaptation. …

The Influence Of Dementia Caregiver Mental Health On Quality Of Care In Argentina, Alejandra Morlett Paredes

Theses and Dissertations

This study examined the connections between cognitive functioning in individuals with dementia and caregiver burden, burden and mental health, mental health and quality of care. One hundred two dementia caregivers from San Lucas, Argentina completed questionnaires assessing these constructs. Caregiver burden, depression, anxiety, and satisfaction with life explained 18.8% of the variance in quality of care – respect and 14.7% of the variance in quality of care – provide. An SEM with generally adequate fit indices uncovered that cognitive functioning in individuals with dementia was inversely associated with caregiver burden, caregiver burden was inversely associated with mental health, and mental …

Disparities In Adverse Childhood Experiences And Sexual Health In The Us: Results From A Nationally Representative Sample, Monique J. Brown

Theses and Dissertations

Background: Adverse childhood experiences (ACEs) are a major public health problem in the US, and have been linked to risky sexual behavior and psychopathology. However, studies examining the link between the wide range of ACEs and sexual health outcomes and behaviors, and the associated mediational role of psychopathology are lacking.

Objectives: The main objectives of this dissertation project were: 1) To determine the association between ACEs and sexual health outcomes and behaviors (early sexual debut, intimate partner violence (IPV) perpetration, and HIV/STIs); 2) To examine the disparities among selected populations; and 3) To assess the mediational role of psychopathology in …

Regulation Of Pancreatic Α And Β Cell Function By The Bile Acid Receptor Tgr5, Divya Prasanna Kumar

Theses and Dissertations

The discovery that bile acids act as endogenous ligands of the membrane receptor TGR5 and the nuclear receptor FXR increased their significance as regulators of cholesterol, glucose and energy metabolism. Activation of TGR5, expressed on enteroendocrine L cells, by bile acids caused secretion of GLP-1, which stimulates insulin secretion from pancreatic β cells. Expression of TGR5 on pancreatic islet cells and the direct effect of bile acids on the endocrine functions of pancreas, however, are not fully understood. The aim of this study was to identify expression of TGR5 in pancreatic islet cells and determine the effect of bile acids …

Stress Management For Cancer Survivors Using A Technologically Adapted Psychosocial Intervention: A Randomized Trial Determining The Effect Of Expressive Writing On Psychoneuroimmunology Based Outcomes, Utkarsh B. Subnis

Theses and Dissertations

Patients with cancer transitioning from completing their final cancer treatments to survivorship are particularly at risk for experiencing psychosocial stress, and the Institute of Medicine (IOM) has referred to these cancer patients as “lost in transition.” In this study, patients with cancer in their transition phase after completing their final radiation treatment were defined as cancer survivors (CS). CS must deal with chronic stressors such as the fear of cancer recurrence as well as the resumption of their roles in their family and work lives. Chronic stress impacts the nervous system and increases secretion of stress hormones (e.g. cortisol) from …