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Modeling And Analysis Of Repeated Ordinal Data Using Copula Based Likelihoods And Estimating Equation Methods, Raghavendra Rao Kurada

Mathematics & Statistics Theses & Dissertations

Repeated or longitudinal ordinal data occur in many fields such as biology, epidemiology, and finance. These data normally are analyzed using both likelihood and non-likelihood methods. The first part of this dissertation discusses the multivariate ordered probit model which is a likelihood method based on latent variables. We show that this latent variable model belong to a very general class of Copula models. We use the copula representation for the multivariate ordered probit model to obtain maximum likelihood estimates of the parameters. We apply the methodology in the analysis of real life data examples.

Though likelihood methods are preferable, there …

Persistence To An Associate Of Applied Science Registered Nurse Degree: The Impact Of Placing Into Developmental Education Courses On Student Success, Caroline Clark Rivera

Educational Leadership & Workforce Development Theses & Dissertations

Student retention and success in nursing school has gained favor in educational research due to an increasing shortage of Registered Nurses. The purpose of this study is to measure the impact of student placement recommendation into developmental education courses on persistence to an Associate of Applied Science Registered Nurse degree. Using ex post facto research methodology rooted in the retention theories of Tinto, Bean and Metzner, and Jeffreys, this study aims to measure the effect of high school diploma type, age, race/ethnicity, and pre-requisite courses on student placement recommendation in developmental education and persistence to an Associate of Applied Science …

Hybrid Inorganic/Organic Nanostructured Tandem Solar Cells: Simulation And Fabrication Methods, Patrick Michael Boland Jr.

Electrical & Computer Engineering Theses & Dissertations

Organic solar cell technologies continue to be an extremely active area of scientific research. With their promise of providing low-cost, easily-processable, multi-application photovoltaics, these devices could very possibly be the most viable and practical form of renewable energy among many being explored. However, significant technological obstacles remain that must be overcome if this technology is to successfully realize the goal of providing abundant energy while simultaneously reducing dependence on fossil fuel-based sources. Compared with inorganic solar photovoltaics, power conversion efficiencies in organics are still too low to compete economically.

Much research has been accomplished over the past three decades in …

Evaluating Methods For Optimizing Classification Success From Otolith Tracers For Spotted Seatrout (Cynoscion Nebulosus) In The Chesapeake Bay, Stacy Kavita Beharry

OES Theses and Dissertations

Identifying the natal sources of fish is an important step in understanding its population dynamics. Adult recruits are often sourced from multiple nursery areas, with good quality locations contributing disproportionately more fish to the adult stock. Because population persistence is strongly influenced by nursery habitat, methods that correctly identify the source of recruits are necessary for effective management. Within the last decade, otolith chemistry signatures have been increasingly used as a natural marker to delineate fish from a mixture of nursery sources. Despite the widespread use of otolith trace element and stable isotope ratios as habitat markers, the statistical approaches …

A Microfluidic Device For Impedance Spectroscopy, Ahmet Can Sabuncu

Mechanical & Aerospace Engineering Theses & Dissertations

Recently, microfluidics has become a versatile tool to investigate cellular biology and to build novel biomedical devices. Dielectric spectroscopy, on the other hand, allows non-invasive probing of biological cells. Information on the cell membrane, cytoplasm, and nucleus can be obtained by dielectric spectroscopy provided that appropriate tools are used in specific frequency ranges. This dissertation includes fabrication, characterization, and testing of a simple microfluidic device to measure cell dielectric properties. The dielectric measurements are performed on human T-cell leukemia (Jurkat), mouse melanoma (B16), mouse hepatoma (Hepa), and human costal chondrocyte cells. Dielectric measurements consist of measuring the complex impedance of …

Namaste: Pedagogical Methods For Designing Yoga & Art Experiences For/With Teen Participants, Tiffani Olivia Bryant

English Theses & Dissertations

Within this study, teens are asked to analyze yoga studio homepages in relation to their experiences with the practice of yoga. This dissertation research engages the teen girls as participants responsible for co-designing the learning constructs through which they make meaning out of their experiences. This research is rooted in informational design, experiential design, and design practices for a teen demographic through the artifact of yoga.

Participant observation is used to examine how eight teen girls understand yoga as a practice, internalize their experiences with yoga, and thusly communicate what they have learned about yoga and a sampling of digital …

Collective Efficacy And Intimate Partner Violence: Community Context, Catherine B. Cowling

Sociology & Criminal Justice Theses & Dissertations

Intimate partner violence is a very serious issue in the United States. In spite of improvements, there is still much work to be done. Policies focusing on formal controls such as arrest, orders of protection, and prosecution have questionable potential. However, collective efficacy and the examination of community context have much to offer the field of intimate partner violence. Collective efficacy, comprised of social cohesion, social capital, and informal social control, may be more effective in reducing intimate partner violence than use of traditional formal social controls alone. These community context variables may also be of great assistance in improving …

Elementary Teachers' Views Of Environmental Education, Rose M. Hotchkiss

Teaching & Learning Theses & Dissertations

The purpose of this research is to examine teachers' views of environmental education (EE) at the elementary level. The study addresses teachers' attitudes toward the EE at the elementary school level and their self-efficacy in teaching EE.

The study's sample consisted of 201 randomly selected kindergarten through fifth grade United States public school teachers. The participants completed an on-line survey with eight percent of the respondents participating in follow up interviews. The questionnaire measured two constructs; Teachers Attitudes Toward EE and Teacher Efficacy in EE. Teachers Attitudes Toward EE had 3 subscales; Advocacy for EE, Stewardship in EE, …

Perceived Satisfaction Of Counseling Doctoral Students With Their Dissertation Chairperson: Examining Selection Criteria And Chairperson Behaviors, Cheryl Warren Neale-Mcfall

Counseling & Human Services Theses & Dissertations

The relationship between doctoral students and their chairperson has been linked to students' successful completion of their dissertation and program of study (Gardner, 2009; Lovitts, 2001). It is often the case that failure to complete the dissertation is what prevents doctoral students from completing their degree. When students do not successfully complete their degrees, attrition rates rise and programs and students feel the burden, both financially and as an investment of time. (Bair & Haworth, 2004). Studies indicate that many students fall short of completing the dissertation, or take much longer than expected, due to a lack of supervision or …

Special Issue On Wireless Sensor And Actuator Networks, Jiming Chen, Karl H. Johanson, Stephan Olariu, Ioannis Ch. Paschalidis, Ivan Stojmenovic

Computer Science Faculty Publications

( First paragraph) WIRELESS Sensor Networks (WSNs), in their various shapes and forms, have greatly facilitated and enhanced the automated, remote, and intelligent monitoring of a large variety of physical systems. These networks consist of a large number of typically small devices, each incorporating sensing, processing, and wireless communications capabilities. Their use has penetrated a plethora of application domains from industrial and building automation, to environmental, wildlife, and health monitoring.

Bcc Skin Cancer Diagnosis Based On Texture Analysis Techniques, Shao-Hui Chuang, Xiaoyan Sun, Wen-Yu Chang, Gwo-Shing Chen, Adam Huang, Jiang Li, Frederic D. Mckenzie

Electrical & Computer Engineering Faculty Publications

In this paper, we present a texture analysis based method for diagnosing the Basal Cell Carcinoma (BCC) skin cancer using optical images taken from the suspicious skin regions. We first extracted the Run Length Matrix and Haralick texture features from the images and used a feature selection algorithm to identify the most effective feature set for the diagnosis. We then utilized a Multi-Layer Perceptron (MLP) classifier to classify the images to BCC or normal cases. Experiments showed that detecting BCC cancer based on optical images is feasible. The best sensitivity and specificity we achieved on our data set were 94% …

2d Face Database Diversification Based On 3d Face Modeling, Qun Wang, Jiang Li, Vijayan K. Asari, Mohammad A. Karim, Manuel Filipe Costa (Ed.)

Electrical & Computer Engineering Faculty Publications

Pose and illumination are identified as major problems in 2D face recognition (FR). It has been theoretically proven that the more diversified instances in the training phase, the more accurate and adaptable the FR system appears to be. Based on this common awareness, researchers have developed a large number of photographic face databases to meet the demand for data training purposes. In this paper, we propose a novel scheme for 2D face database diversification based on 3D face modeling and computer graphics techniques, which supplies augmented variances of pose and illumination. Based on the existing samples from identical individuals of …

Localized Surface Plasmon Resonance Of Single Silver Nanoparticles Studied By Dark-Field Optical Microscopy And Spectroscopy, Wei Cao, Tao Huang, Xiao-Hong Nancy Xu, Hani E. Elsayed-Ali

Electrical & Computer Engineering Faculty Publications

Localized surface plasmon resonance (LSPR) of Ag nanoparticles (NPs) with different shapes and disk-shaped Ag NP pairs with varying interparticle distance is studied using dark-field optical microscopy and spectroscopy (DFOMS). Disk-, square-, and triangular-shaped Ag NPs were fabricated on indium tin oxide-coated glass substrates by electron beam lithography. The LSPR spectra collected from single Ag NPs within 5×5 arrays using DFOMS exhibited pronounced redshifts as the NP shape changed from disk to square and to triangular. The shape-dependent experimental LSPR spectra are in good agreement with simulations using the discrete dipole approximation model, although there are small deviations in the …

Unpacking Faculty Engagement: The Types Of Activities Faculty Members Report As Publicly Engaged Scholarship During Promotion And Tenure, Chris R. Glass, Diane M. Doberneck, John H. Schweitzer

Educational Leadership & Workforce Development Faculty Publications

While a growing body of scholarship has focused on the personal, professional, and organizational factors that influence faculty members’ involvement in publicly engaged scholarship, the nature and scope of faculty publicly engaged scholarship itself has remained largely unexplored. What types of activities are faculty members involved in as publicly engaged scholarship? How does their involvement vary by demographic, type of faculty appointment, or college grouping? To explore these questions, researchers conducted a quantitative content analysis of 173 promotion and tenure documents from a research-intensive, land-grant, Carnegie Classified Community Engagement university and found statistically significant differences for the variables age, number …

An Investigation Of Higher-Order Thinking Skills In Smaller Learning Community Social Studies Classrooms, Christopher Fischer, Linda Bol, Shana Pribesh

Educational Leadership & Workforce Development Faculty Publications

This study investigated the extent to which higher-order thinking skills are promoted in social studies classes in high schools that are implementing smaller learning communities (SLCs). Data collection in this mixed-methods study included classroom observations and in-depth interviews. Findings indicated that higher-order thinking was rarely promoted in SLC classes. Interview data suggests several factors affecting teaching for higher-order thinking in SLC social studies classrooms. These include: high stakes testing, pacing pressures, teachers' dispositions and training, and teacher autonomy.

Spatio-Temporal Variations In Soil Moisture And Physicochemical Properties Of A Typical Semiarid Sand-Meadow-Desert Landscape As Influenced By Land Use, L. Duan, T. Liu, X. Wang, G. Wang, L. Ma, Y. Luo

Civil & Environmental Engineering Faculty Publications

A good understanding of the interrelations between land cover alteration and changes in hydrologic conditions (e.g., soil moisture) as well as soil physicochemical properties (e.g., fine soil particles and nutrients) is crucial for maintaining the fragile hydrologic and environmental conditions of semiarid land, such as the Horqin Sandy Land in China, but is lacking in existing literature. The objectives of this study were to examine: (1) spatio-temporal variations of soil moisture and physicochemical properties in semiarid land; and (2) how those variations are influenced by land cover alteration. Using the data collected in a 9.71 km2 well-instrumented area of the …

Exploring The Effects Of An Art Based Trauma Protocol With An Active Duty Police Officer Experiencing Symptoms Of Posttraumatic Stress Disorder, Khaki Wieters

EVMS School of Health Professions Theses & Dissertations

Because of repeated exposure to traumatic events as part of their job requirements, Posttraumatic Stress Disorder is a common problem found among police officers. Although treatments in some agencies are limited, they can include, Critical Incident Stress Management, mandatory referrals to mental health professionals, and trained peer support. Art therapy is an efficient treatment for trauma because it bypasses defenses and aids in processing and integrating traumatic imagery by naturally connecting the brain’s right and left hemispheres. Police diagnosed with PTSD may benefit from art therapy since it can penetrate resistance and has proven effective for processing traumatic imagery.

This …

3,4-Methylenedioxymethamphetamine Alters Left Ventricular Function And Activates Nuclear Factor-Kappa B (Nf-Kappab) In A Time And Dose Dependent Manner, David A. Tiangco, Sapna Halcomb, Frank A. Lattanzio Jr, Barbara Y. Hargrave

Bioelectrics Publications

3,4-Methylenedioxymethamphetamine (MDMA) is an illicit psychoactive drug with cardiovascular effects that have not been fully described. In the current study, we observed the effects of acute MDMA on rabbit left ventricular function. We also observed the effects of MDMA on nuclear factor-kappa B (NF-kappa B) activity in cultured rat ventricular myocytes (H9c2). In the rabbit, MDMA (2 mg/kg) alone caused a significant increase in heart rate and a significant decrease in the duration of the cardiac cycle. Inhibition of nitric oxide synthase (NOS) by pretreatment with L-NAME (10 mg/kg) alone caused significant dysfunction in heart rate, systolic pressure, diastolic pressure, …

Current Status And Long-Term Trends In Water Quality And Living Resources In The Virginia Tributaries And Chesapeake Bay Mainstem From 1985 Through 2009, Daniel M. Dauer, Harold G. Marshall, John R. Donat, Michael F. Lane, Suzanne C. Doughten, Frederick A. Hoffman, Raghavendra Kurada

Status and Trends for Virginia Chesapeake Bay

The period prior to the implementation of the Chesapeake Bay Monitoring Program was characterized by a marked decline in the water quality of the Chesapeake Bay. The disappearance of submerged aquatic vegetation in certain regions of the Bay, declines in the abundance of some commercially and recreationally important species, increases in the incidence of low dissolved oxygen events, changes in the Bay's food web, and other ecological problems have been related to the deteriorating water quality (e.g. USEPA, 1982,1983;Officer et al.,1984; Orth and Moore, 1984). The results of concentrated research efforts in the late 1970s and early 1980s stimulated the …

Foundational Checklist Of The Amphibians Of Wise County, Virginia, Sarah R.A. Davidson, David L. Chambers

Virginia Journal of Science

The Appalachian Mountains are arguably home to the highest degree of amphibian diversity in the world, particularly caudate (salamander) biodiversity. Despite the high degree of amphibian endemism in the Appalachians, several regions remain unsurveyed for amphibian species. In addition to this knowledge gap, we are in the midst of alarming amphibian biodiversity loss. Thus, it is of the utmost importance to bridge this knowledge gap by conducting surveys before some of these amphibian species are lost. We surveyed Wise County (previously unsurveyed county in the Appalachian Mountains with no records existing in the primary literature) over two years to assess …

Thomas Orr Sitz (1944-2010)

Virginia Journal of Science

Obituary for Thomas Orr Sitz.

Mathematical Manipulative Models: In Defense Of "Beanbag Biology", John R. Jungck, Holly Gaff, Anton E. Weisstein

Biological Sciences Faculty Publications

Mathematical manipulative models have had a long history of influence in biological research and in secondary school education, but they are frequently neglected in undergraduate biology education. By linking mathematical manipulative models in a four-step process-1) use of physical manipulatives, 2) interactive exploration of computer simulations, 3) derivation of mathematical relationships from core principles, and 4) analysis of real data sets-we demonstrate a process that we have shared in biological faculty development workshops led by staff from the BioQUEST Curriculum Consortium over the past 24 yr. We built this approach based upon a broad survey of literature in mathematical educational …

Contributors, Marc Ouellette

Reconstruction: Studies in Contemporary Culture

Information about contributors to articles in volume 10, issue 4 of Reconstruction.

Evolution, Popular Culture, And The Nature Of Scientific Knowledge, James Clinton

Reconstruction: Studies in Contemporary Culture

This article presents a view of science that counters the teleological and authoritative way in which it is presented in arenas of popular discourse ranging from public schools, science magazines (such as Wired), community meetings, and popular books written by scientists. Noting the strange conflation of “evolution” (a branch of science) and “science” (as a way of thinking), the essay presents psychoanalytic and scientific arguments that suggest that evolution is equated with science in the public because evolution represents the return of the repressed element that founds any discourse which seeks to remain self contained. In science, this repressed …

"Rectification Of Human Names": E.P. Thompson And Contemporary Debates On Historical And Epistemological Discourse, Manuel Yang

Reconstruction: Studies in Contemporary Culture

E. P. Thompson used the Confucian trope of “rectification of human names” to summarize the major themes of his work. Such rectification has both political and scholarly ramifications that extend to poststructuralist debates over historical discourse (Ranajit Guha’s meditation on the method of Subaltern Studies, Hayden White’s theory of rhetorical universalism); organic relationship between working-class gesture, linguistic philosophy, and political economy (as exemplified in Piero Sraffa's renowned contribution to the "epistemological break" between the early and late Ludwig Wittgenstein's philosophy); and the universality of class struggle in defining the crucial intellectual breakthroughs of the 1970s, from the works of Michel …

Editors’ Introduction: What Is Outsider Criticism?, Marc Ouellette

Reconstruction: Studies in Contemporary Culture

[First paragraph]

In 1979, Jean-François Lyotard published the results of a study he was commissioned to write for the Conseil des universités du Québec in which he made the claim that, in a university system devoted to functionalism rather than experimentation, “it is safe to assume that responsibility for [experimentation] will devolve upon extrauniversity networks.” This proclamation may have been shocking to university administrators, who have often equated the university with knowledge as if such a linking were inevitable, but from Lyotard’s perspective of a growing, capitalist-fueled technocracy, and now ours, in which this technocracy has grown in size and …

"Beyond Bio2010: Celebration And Opportunities" At The Intersection Of Mathematics And Biology, John R. Jungck, Holly D. Gaff, Adam P. Fagen, Jay B. Labov

Biological Sciences Faculty Publications

With this special edition of CBE-LSE, which focuses on connections between and integration of the biological and mathematical sciences, it is especially fitting that we report on an important symposium, Beyond BIO2010: Celebration and Opportunities,1 which was held at the National Acad- emy of Sciences (NAS) in Washington, D.C. on May 21–22, 2010. This symposium was organized to assess what progress has been made in addressing the challenges and recommendations in the National Research Council’s (NRC) report: BIO2010: Transforming Undergraduate Education for Future Research Biologists (NRC, 2003a). Most of the presen- tations and posters at this event emphasized the increasing …

A Novel Piezoelectric Device With Dual Functions Of Studying Biological Soft Tissues, Avin A. Jamadagni

Mechanical & Aerospace Engineering Theses & Dissertations

This thesis presents the design of a novel piezoelectric device with dual functions of studying soft biological tissues. The device consists of a central circular plate and a set of flexural beams. The flexural beams are partially covered with piezoelectric film for integrated transduction. It can function as a force sensor for measuring the mechanical behavior of a tissue sample and a load applier for mimicking physiological loads experienced by the tissue sample in vivo, while the mechanical behavior can be visually observed under a microscope simultaneously. By combining the classic theories in solid mechanics and piezoelectricity, the performance of …

Characterization Of Metastasis-Associated Cell Surface Glycoproteins In Prostate Cancer, Lifang Yang

Theses and Dissertations in Biomedical Sciences

Prostate cancer (PCa) is a major health problem in males in the United States. Its lethality is mostly attributed to the primary tumor metastasizing to distant sites that are highly resistant to conventional therapies. Serum Prostate Specific Antigen (PSA) is the only protein biomarker used in clinic for prediction of prostate cancer recurrence following local therapies. Nonetheless, PSA lacks the ability to predict the behavior of an individual tumor in an individual patient. Therefore, development of reliable biomarkers for detection of metastatic potential in primary tumors, as well as discovery of new therapeutic targets, is in a great need for …

Comparison Of Ice Core Dissolved Organic Matter From A Greenland Ice Core By Nanospray Fourier Transform Ion Cyclotron Resonance Mass Spectrometry, Joshua Jeremiah Shiloh Marsh

Chemistry & Biochemistry Theses & Dissertations

Recent studies of ice cores have embarked on the task of determining the classes of dissolved organic matter (DOM) present in melt-water from the cores collected in numerous locations in the northern and southern hemispheres. This DOM originally derives from wet precipitation and is thought to reflect atmospheric organic matter derived from anthropogenic and non-anthropogenic sources. Because the amount of DOM is so low, previous studies have necessarily used large sample volumes (greater than 500 mL) to concentrate sufficient ice core DOM necessary for mass spectral analysis. Solid phase extraction (SPE) with C₁₈ resins was followed by evaporative concentration …