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Physical And Chemical Properties Of A New Mineral Trioxide Aggregate Material, David Lowell Spencer

Theses and Dissertations

The objective of this study was to compare the time to final set and compressive strength of the white mineral trioxide aggregate (MTA) formulation to the original grey MTA. To test compressive strength, each MTA formulation was placed into Teflon split molds for four hours at 37° Celsius (C) and 100% humidity. Compressive strength of both MTA formulations was measured at 24 hours (n=12) and 21 days (n=19) using an Instron Testing Machine. For determination of time to final set, each MTA formulation (n=6) was placed into a metal mold and maintained at 37° C and 100% humidity while setting. …

Use Of A Portland Cement Accelerator With Mineral Trioxide Aggregate, M. Scott Monts

Theses and Dissertations

The use of Mineral Trioxide Aggregate (MTA) is gaining popularity among clinicians. Despite the many ideal qualities it possesses, it is often difficult to manipulate and often requires a second appointment for placement of a restoration to allow for setting. If the time to set of MTA can be accelerated to a single appointment time frame without significantly altering its properties, then MTA may gain even wider acceptance. The purpose of this study is to identify the percentage of a Portland Cement Accelerator (PCA), that when added to MTA, will decrease the time to set of MTA towards a single …

Childhood Exposure To Interparental Conflict: Memory Biases And Intergenerational Patterns Of Conflict In Romantic Relationships, Christine A. Nelson

Theses and Dissertations

Testing a model that explains the ways in which interparental conflict shapes later intimate relationships was the goal of the present study. Participants were 94 college students at Virginia Commonwealth University, a large state university with a diverse student body. The study found that violence occurs with alarming frequency in the dating relationships of university students. Analyses also revealed an intergenerational pattern of violence in which individuals from high conflict homes were more likely to use violent conflict resolution strategies in their own adult romantic relationships. Specifically, young adults from homes characterized by high levels of verbal conflict and minor …

Narrating Friendship: The Reciprocal Relationship Between J.B. Childers And Myself, James Thomas Engelmann

Theses and Dissertations

For the past ten months I have explored the life of a deceased artist named Joseph Barley "J.B." Childers. In the graduate catalog Gregory Volk summarizes Childers as, "an alienated Korean War Veteran, who took up painting as a refuge from his troubles, and who also doesn't exist. Childers who is naturally right-handed, painted everything left-handed because of a war wound, and so Engelmann, who is left-handed, painted with his right hand, which is quite a limitation." Of course, there's more to the story than that and the writings that follow will explain many of my reasons for pursuing this …

Effects Of Emphysema And Chronic Hypoxemia On Skeletal Muscle Oxygen Supply And Demand, John D. Lowman Jr.

Theses and Dissertations

Skeletal muscle dysfunction in chronic obstructive pulmonary disease (COPD) is a condition in which peripheral skeletal muscle undergoes myopathic changes which impair muscle function, limit physical performance, and can lead to significant disability. While the etiology of the dysfunction is unknown, this study was conducted to test the hypothesis that chronic hypoxemia leads to alterations in oxygen transport and muscle function. A primary objective was to validate elastase-induced emphysema in rats as an animal model of skeletal muscle dysfunction in COPD.Arterial blood gases were used to determine the severity of hypoxemia and sodium dodecyl sulfate- polyacrylamide gel electrophoresis was used …

Growth And Deterioration, Brooke A. Hine

Theses and Dissertations

I use porcelain clay because it allows me to focus on the subtle color shifts between white, beige, and gray. The forms I make in clay are associated with tangled roots, naked tree branches, hollow logs, and bones. I reveal this with a dense mass of curvilinear hollow forms that stack into a rhythmic linkage. They twist and turn, relying on gravity to dictate their structure within the installation. The ends of some are closed while others remain open to expose their interior. The tearing and perforations on the surface of each piece are employed to emphasize deterioration. In opposition …

The Social Network And Attachment Bases Of Loneliness, David M. Ouellette

Theses and Dissertations

This thesis tests Robert S. Weiss's 1973 theory of loneliness, which claims two types of loneliness: emotional and social. Emotional loneliness is the affective reaction to the absence of a close attachment bond. Social loneliness stems from inadequate integration into a social network. Undergraduate residents of a university dormitory completed questionnaires on loneliness, attachment, personality, and relationships with other dorm residents. Patterns of relational ties among participants were evaluated using social network analysis, specifically density, tie strength, and four forms of centrality. Results reveal that, while controlling for neuroticism, the network measure of outdegree and the two attachment dimensions accounted …

Determinants Of Prenatal Care And Supplement Use: The Case Of Honduras, Catherine E. Henze

Theses and Dissertations

Context: Literature suggests that prenatal care and prenatal supplement use improves pregnancy outcomes. However, we do not know the factors associated with prenatal care and supplement use in Honduras.Objective: To identify characteristics of Honduran women who are the least and most likely to use prenatal care and supplements.Methods: Data from a 2001 Honduras cross-sectional survey of women was used to assess their use of prenatal care and supplements. All data was weighted, resulting in a sample size of n = 5647 women who had a live birth since January 1996. Bivariate and multivariate analyses were used to examine factors associated …

Iii-Nitride Semiconductors Grown By Plasma Assisted Molecular Beam Epitaxy, Lei He

Theses and Dissertations

III-nitride semiconductors are of great interest owing to their commercial and military applications due to their optoelectronic and mechanical properties. They have been synthesized successfully by many growth methods. Among them, molecular beam epitaxy (MBE) is a promising epitaxial growth method owing to precise control of growth parameters, which significantly affect the film properties, composition, and thickness. However, the understanding of growth mechanism of III-nitride materials grown in this growth regime is far from being complete.In this dissertation, GaN and AIGaN growth mechanism under metal-rich conditions were investigated. The Ga surface desorption behavior during the growth was investigated systematically using …

The Psychometric Properties Of The Inner Strength Questionnaire For Women With Chronic Health Conditions, Kristi Leanne Lewis

Theses and Dissertations

The purpose of this research was to develop and test an instrument to measure or quantify the construct of inner strength. Inner strength was synthesized into a theory based on twelve years of qualitative data from direct participant quotes, defined by Roux et al. (2002) as a central human resource that promotes well-being and healing. The inner strength questionnaire (ISQ) has undergone extensive psychometric evaluation which resulted in several versions. The third version had 37-items and was believed to have four subscales that mirrored the theoretical themes that emerged through the qualitative data. The sample was composed of 281 women …

Surface Characteristics Of Bacillus Spores, Darlene Danette Sabio

Theses and Dissertations

Rapid isolation and identification of spores from various environmental samples is necessitated because anthrax spores can be used as biological weapons. The hydrophobic nature of spores may allow for their rapid concentration and partial purification from contaminating materials. In this study, spores from four taxonomic groups of Bacillaceae were isolated, purified and characterized for hydrophobicity by hexadecane partitioning, surface morphology by scanning electron microscopy, and steady-state fluorescence by spectroscopy. The morphology of spores was similar within taxonomic groups and dissimilar between groups. Spore hydrophobicity ranged from 0.3% to 65% and all spores had fluorescence emission peaks at 335 nm and …

The Transformation Of Electricity In My Brain, Claire Watkins

Theses and Dissertations

This thesis is an exciting and enthralling story about the history of the world as seen through the eyes of Claire Watkins. The story takes place in the dusty corners of her art studio in the old confederate capital, Richmond, Virginia. Ms. Watkins leads her audience through such unsuspecting places as her brain, the life of an African Dung Beetle, the center of an atom and the dark reaches of outer space. The story is inspirational and thought provoking. It will force you to see the world as an interconnected web that weaves your life together with the cosmos. A …

Soul Hunting, Guido Esteban Alvarez

Theses and Dissertations

According to the Webster's unabridged dictionary, a mania is an excessively intense enthusiasm, interest, or desire; a craze. I experience a mania on a daily basis: I take photographs. I trap photographs inside flat, airless fish tanks where time stands still. The creatures captured inside the tanks resurrect every time I see them to remind me of a sound, an odor, a flavor, and, ultimately, a feeling I once experienced and now cherish. This project will attempt to show the energy captured in my photographic archives as a journey through my memories using an experimental interactive method.

Gas Phase Studies Of Molecular Clusters Containing Metal Cations, And The Ion Mobility Of Styrene Oligomers, Edreese Housni Alsharaeh

Theses and Dissertations

This study is divided into three parts. Part I deals with the mechanism of the self-initiated polymerization (or thermal polymerization) of styrene in the gas phase. In this work, we present the first direct evidence for the thermally self-initiated polymerization of styrene in the gas phase. Our approach is based on on-line analysis of the gas phase Oligomers by mass-selected ion mobility. The mobility measurements provide structural information on the ionized oligomers based on their collision cross-sections (Ω) which depend on the geometric shapes of the ions. Theoretical calculations of possible structural candidates of the Oligomers ions are then used …

Obesity And Health Status Among Urban Vs. Suburban Elderly In Philadelphia And Surrounding Counties, Ockidde Dufayne Harris

Theses and Dissertations

Obesity is a dangerous health condition affecting approximately 30% of all Americans and can be attributed to 300,000 deaths a year. Obesity has been found to disproportionately affect Blacks, Latinos, and those with lower SES. Although obesity is a problem for all age groups, its prevalence is highest among those 60-74 years of age. Studies have shown that there is an association between obesity and chronic conditions such as cardiovascular disease, arthritis, cancers, and type-2 diabetes. According to the Centers for Disease Control, chronic health conditions affect 80% of all elderly persons, many times limiting function and decreasing quality of …

Novel Apparatus To Control Electrospinning Fiber Orientation For The Production Of Tissue Engineering Scaffolds, Eugene David Boland

Theses and Dissertations

The conception of electrospinning can trace its roots back more than 400 years, when it was observed that rubbed amber can deform a droplet of water on a smooth surface, and is based upon simple concepts of charge separation and surface tension. Since that time, considerable effort has been directed at both the cause and utility of this phenomenon. The specific aim of this dissertation project was to develop an automated electrostatic processing apparatus that was capable of controlling the three-dimensional architecture of an electrospun scaffold to further improve its utility in tissue engineering. The efficacy of using this technique …

Rabies In Virginia, 1989-2003: With Particular Attention To Animals, Geographic Distribution, And Virus Variant, William Andrew Holzgrefe

Theses and Dissertations

Objectives: The description of the raccoon rabies epizootic in Virginia over fifteen years (1989-2003). Methods: Using simple statistical methods and a geographic information system (GIS)-based approach, and fifteen years worth of animal surveillance data, the progress of this epizootic has been charted in terms of the geographic spread of the disease, the major animal species affected by the disease and its spread, and the exposure and risk to humans and livestock animals presented by the expansion of the geographic range. Results: The resulting descriptive study illustrates the eastward expansion of the epizootic, the mushrooming of the disease in the northern …

Perpetual Novelty, Brian Caverly

Theses and Dissertations

Within this thesis is a mapping out of the processes, concepts, and influences, behind the sculptural practice of Brian Caverly. From Complex Adaptive Systems to the world of order of Michel Foucault to the reexamination of the Modernist movement by Yve Alain Bois and Rosalind Krauss, a rhizomatic path of connections and lines form and cross over, weaving together into a swarming mayhem of over population. Out of this chaos and order grow complex installations and constructions that are inherently bound by the system of their making, yet attempt at every turn to escape conformity.

Characterization Of Aligned Carbon Nanotube/Polymer Composites, Sumanth Banda

Theses and Dissertations

The main objective of this thesis is to efficiently disperse and align SWNTs in two different polymer matrices to obtain an orthotropic composite whose strength, stiffness and electrical properties depend on the orientation of the SWNTs. The SWNTs are successfully dispersed and aligned in a polyimide matrix and a polymer blend of UDMA/HDDMA. In-situ polymerization under sonication is used to disperse the SWNTs in polyimide matrix and sonication is used to disperse SWNTs in the UDMA/HDDMA matrix. In both cases, an electric field is used to align the SWNTs in the polymer matrices. In the polyimide, the SWNTs are aligned …

Effect Of Stochastic Dead Space On Noise In Avalanche Photodiodes, Oh-Hyun Kwon, Majeed M. Hayat, Joe C. Campbell, Bahaa E.A. Saleh, Malvin Carl Teich

Electrical and Computer Engineering Faculty Research and Publications

A stochastic dead-space model for impact ionization is developed and used to study the effect of the soft nature of the ionization capability of carriers on the excess noise factor of avalanche photodiodes. The proposed model is based on the rationale that the gradual, or soft, transition in the probability density function (PDF) for the distance from birth to impact ionization can be viewed as that resulting from uncertainty in the dead space itself. The resulting soft PDF, which is parameterized by a tunable softness parameter, is used to establish the limitations of the existing hard-threshold ionization models in ultrathin …

Effects Of Sputter Deposition Parameters On Stress In Tantalum Films With Applications To Chemical Mechanical Planarization Of Copper, Jeffrey L. Perry

Theses

Attempts to introduce a CMP process for copper damascene features at Rochester Institute of Technology were stymied by adhesion failures of the Ta/Cu film stack. This work was undertaken to investigate the effect of stress in the films on adhesion and to develop a viable CMP process for Cu damascene technology. In depth studies of stress as a function of sputter deposition conditions revealed that stress in Ta layers could vary from -1700 MPa compression to +800 MPa tensile for deposition pressures over a range of 2-20 mTorr for films having a nominal thickness of 0.25 μm. For a fixed …

The Wrong Way To Equality: Privileging Consent In The Trafficking Of Women For Sexual Exploitation, Beverly Balos

Articles

Chamoli lived near the birthplace of the Buddha in Nepal. When she was 16, she met a young man and fell in love with him. He promised to marry her but insisted that she come away with him to India. So one day she ran away with the boyfriend and crossed the border to India on foot. From there she and her boyfriend took a train to the Indian city of Poona. Once they had reached Poona, Chamoli was taken to a house where there was an older Nepali lady and many young girls. The lady gave her boyfriend some …

The Limits Of Business Limited Liability: Entity Veil Piercing And Successor Liability Doctrines, John Matheson

Articles

The quest for limited liability in business enterprises and transactions has been a driving force in the development of business organization law for centuries. The historical development of corporations and limited partnerships evidences this primary goal. The recent development of the modern forms of limited liability partnerships and limited liability companies proves that this quest continues unabated. In addition, parties to significant business transfer transactions have long sought by construct and contract to apportion and limit their respective legal responsibilities and liabilities.Counterbalancing this inexorable trend toward limited liability has been the penchant of common law jurisprudence to define its limits. …

Assessment Of Organic And Inorganic Pollutants In The Offshore Sediments, Dubai, Uae., Haifa Darwish Ahmad Al Darwish

Theses

The investigated area covers the maximum fragments of Dubai offshore in the Arabian Gulf. The sediment samples were collected from fifteen stations starting by Al-Mamzar mouth and ending by Ras Ghantoot in order to assess the organic and inorganic pollutants affecting the coastal region in Dubai.

The textural class was determined through grain-size analysis and the mineral composition was identified by X-Ray diffraction. The organic pollutants were characterized through the determination of Total Organic Carbon (TOC), Total Kjeldahl Nitrogen (TKN), Total Petroleum Hydrocarbons (TPH), Polycyclic Aromatic Hydrocarbons (PAHs), Polychlorinated biphenyls (PCBs) and individual polychlorinated biphenyls. On the other hand the …

Faith-Based Organizing And Partnerships In A Pittsburgh Neighborhood: A Look At East Liberty, Damon Bethea

Electronic Theses and Dissertations

The East Liberty neighborhood of Pittsburgh has a fascinating blend of African American churches and racially integrated churches -- all within this African American neighborhood in Pittsburgh's East End. In this research project, I will explore how several East Liberty churches are working with other churches (or faith-based organizations [FBOs]) and organizations within the East Liberty neighborhood to provide various social services to those within this predominantly African American community. The research questions for this project are: 1) How does the racial composition of the church community affect their relationship with the residents of East Liberty whom they serve? 2) …

Does Excessive Absence From Class Lead To Lower Levels Of Academic Achievement, Janet L. Faison

OTS Master's Level Projects & Papers

Based on this problem, the following hypothesis has been proposed: 1. Students who have higher records of absenteeism (absent four times or more during a given semester) will have lower academic achievement levels (GPA) while attending community college.

Does Participation In The Academic Continuance Experience For Success Program Increase Academic Achievement And Persistence Of Students Readmitted From Suspension, Norlisa Mayes

OTS Master's Level Projects & Papers

The purpose of this study was to determine if participation in an intervention program improved academic achievement and retention of at-risk college students at Old Dominion University.

Coalescence Remnant Of Spinning Binary Black Holes, J Baker, M. Campanelli, C. O. Lousto, R. Takahashi

Physics & Astronomy Faculty Publications

We compute the gravitational radiation generated in the evolution of a family of close binary black hole configurations, using a combination of numerical and perturbative approximation methods. We evolve the binaries with spins s aligned or counteraligned with the orbital angular momentum from near the innermost stable circular orbit down to the final single rotating black hole. For the moderately spinning holes studied here the remnant Kerr black holes formed at the end of an inspiral process have rotation parameters a/M≈0.72+0.32(s/mH), suggesting it is difficult (though not excluded) to end up with near maximally rotating holes from such scenarios.

Generation Of The Transient Electrical And Spontaneous Magnetic Fields By Solid State Combustion, Karen S. Martirosyan, J. R. Claycomb, J. H. Miller Jr., D. Luss

Physics & Astronomy Faculty Publications

Experiments revealed that transient electric field intensities up to 2.5 V/cm were generated during the initial period of combustion synthesis of the ferromagnetic products before the maximum temperature was reached. This occurred when the iron particles were partially oxidized and the reaction product was mainly magnetite sFe3O4d. The electromagnetic field caused spontaneous magnetization of the product in the postcombustion zone. Magnetic field values up to 4 µT formed after the sample temperature fell below the Curie temperature and the initial reactants were completely converted to the ferromagnetic phase PbFe12O19. Increasing the volume of the samples increases the absolute residual magnetic …

Setting Upper Limits On The Strength Of Periodic Gravitational Waves From Psr J1939+2134 Using The First Science Data From The Geo 600 And Ligo Detectors, B. P. Abbott, R. Abbott, Mario C. Diaz, Wm. R. Johnston, Joseph D. Romano, Cristina V. Torres

Physics & Astronomy Faculty Publications

Data collected by the GEO 600 and LIGO interferometric gravitational wave detectors during their first observational science run were searched for continuous gravitational waves from the pulsar J1939+2134 at twice its rotation frequency. Two independent analysis methods were used and are demonstrated in this paper: a frequency domain method and a time domain method. Both achieve consistent null results, placing new upper limits on the strength of the pulsar’s gravitational wave emission. A model emission mechanism is used to interpret the limits as a constraint on the pulsar’s equatorial ellipticity.