Digital Commons Network^™

The Effects Of Smooth Muscle Cells On Engineered Microvasculatures In Fibrin Hydrogels, Areck A. Ucuzian

Dissertations

Capillaries are comprised of two cell types: the endothelial cells (ECs) which line the lumen of the capillary, and the supporting pericytes which are closely apposed to the abluminal surface of the capillary wall (sometimes called mural cells). These pericytes are phenotypic derivations of mesenchymal organ stromal cells (from smooth muscle cells and fibroblasts in blood vessels, for example), are recruited and incorporate into the neocapillaries, and are known to mediate reciprocal interactions with ECs during angiogenesis. The overall purpose of this project is to determine how smooth muscle cells (SMCs) affect angiogenesis during microvascular development in fibrin hydrogels using …

Using Robust Standard Errors To Combine Multiple Regression Estimates With Meta-Analysis, Ryan T. Williams

Dissertations

Combining multiple regression estimates with meta-analysis has continued to be a difficult task. A variety of methods have been proposed and used to combine multiple regression slope estimates with meta-analysis, however, most of these methods have serious methodological and practical limitations. The purpose of this study was to explore the use of robust variance estimation for combining commonly specified multiple regression models and for combining sample-dependent focal slope estimates from diversely specified models. A series of Monte-Carlo simulations were conducted to investigate the performance of a robust variance estimator for each of these approaches. Key meta-analytic parameters were varied throughout …

Cell Biology Of Foxp3+ Regulatory T Cells, Mariko Takami

Dissertations

T cells play a central role in the immune response to fight against pathogens and orchestrate other immune cells. An overreactive immune response can lead to autoimmune diseases, therefore the immune system must possess negative regulation mechanisms. In the periphery, naturally arising regulatory T cells (nTregs) negatively regulate immune responses and play an important role in maintaining immune homeostasis. When antigens are present, conventional CD4+ T cells recognize their cognate antigen and proliferate. After pathogen clearance, expanded effector T cells eventually decline in number due to activation induced cell death (AICD) to terminate immune response. However, it is not understood …

Spectroelectrochemical Studies Of The Reductive Intermediates Of Anthraquinone-2,6-Disulfonate In Aqueous Media, Anna Weiss

Dissertations

Reactive intermediates in the reduction of anthraquinone-2,6-disulfonate (AQDS) by dithionite combine to form a transient dimer which has shown to give rise to a series of charge transfer bands in the visible range (600-750 nm). Additional wavelengths associated with these intermediate species have been observed at wavelengths 402, 444 and 510 nm. These transient intermediates are generated as dithionite decomposition products re-oxidize AQDS. Evidence of the dimer was also found in experiments in which reduction of AQDS was achieved electrochemically by the use of a potentiostat. This implies three things: 1. dithionite is not required for dimerization of reactive intermediates; …

Romans 1:18-2:11 And The Substructure Of Psalm 106(105): Evocations Of The Calf?, Alexander James Lucas

Dissertations

Employing an architectural metaphor inspired by C. H. Dodd and utilizing methodology that draws from Richard B. Hays and Francis Watson, this dissertation presents a primary proposal and secondary sketch. The primary proposal is that both constitutively and rhetorically (through ironic, inferential, and indirect application), Ps 106(105) serves as the substructure for Paul's argumentation throughout Rom 1:18-2:11. Constitutively, Rom 1:18-32 (especially vv. 22-32) hinges on the triadic interplay between "they (ex)changed" and "God gave them over," an interplay that creates a sin-retribution sequence with an a-ba-ba-b pattern (vv. 22-23, 24-25, 26-27, 28-32). Both elements of this a-ba-ba-b pattern derive from …

Divine Sovereignty, Divine Providence, And Prayer In The Thought Of Evagrius Ponticus, Chris Steven Gombos

Dissertations

In the thought of Evagrius Ponticus, we discern an interdependent relationship between prayer and theological belief, particularly between prayer and divine sovereignty and divine providence. We find that Evagrius's teachings on divine sovereignty and divine providence inform and govern his teachings on prayer, specifically the forms of prayer known as petition and pure prayer. And conversely Evagrius's teachings on prayer inform and deepen his teachings on divine sovereignty and divine providence, thereby demonstrating the full interdependence between spiritual practice and theological belief in the thought of one of the early Church's monastic masters.

The first chapter is divided into two …

Music For Mercer's: The Mercer's Hospital Music Collection And Charity Music In Eighteenth-Century Dublin., Tríona O'Hanlon

Dissertations

This thesis examines and analyses the contents of the Mercer’s Hospital Music Collection. The collection includes fifty manuscript and seven printed volumes of
music containing works by Handel, Greene, Boyce, Purcell, Corelli, Humfrey, Avison, Barsanti, Stanley and Festing. Selected works were performed at the Mercer’s Hospital benefit concerts, established in April 1736 to provide important financial support to the
hospital, which opened on Stephen Street, Dublin in 1734. Mercer’s was the first voluntary Dublin hospital to initiate a series of benefit concerts. The Mercer’s benefit concerts attracted the participation of a wide range of Dublin-based performers, both singers and instrumentalists. …

Populus Defense And Stress Response Regulation During Ectomycorrhizal Symbiosis With Laccaria As Revealed By Global Transcriptome Analysis, Avinash Sreedasyam

Dissertations

No abstract provided.

Numerical Studies Of Supersonic Jet Impingement On A Flat Plate, Michael R. Brown

Dissertations

No abstract provided.

Continuous- And Discrete-Time Structured Malaria Models And Their Dynamics, Junliang Lu

Dissertations

No abstract provided.

A Physically-Derived Nonquasi-Static Model Of The Ferroelectric Transistor For Computer-Aided Device Simulation And Its Application In Analog Circuits, Rana M. Sayyah

Dissertations

No abstract provided.

Introduction Of Critical Stress State Criterion To Predict Bond Strength Between Frp And Concrete Substrate, Shigeyuki Ueno

Dissertations

No abstract provided.

Toward A Holistic Interdisciplinary Model Of Human Being: A Hebraic-Christian Perspective Of The Human Observer And Its Beneficial Impact On The Theology-And-Science Dialogue, Society, And The Environment, Karen K. Abrahamson

Dissertations

Problem

A challenge faced by the theology-and-science dialogue is how to effectively communicate across disciplinary lines. The community assumes that there is a methodology or cluster of methodologies that allows for interdisciplinary conversation to take place. However, the community is not in agreement about how this process should occur or the hermeneutical principles that should guide it. Is it possible to surmount the problem of methodological compatibility and to generate mutually beneficial and fruitful dialogue through seeking a point of commonality between all the disciplines of the theology-and-science dialogue?

Purpose

The purpose of this dissertation is to discover a philosophical …

Development Of Thermal Management Schemes For High Heat Flux Applications Using Two-Phase Spray Cooling Techniques, Richard Opoku

Dissertations

Energy conversion devices produce large heat loads during operation and therefore efficient thermal management schemes for their optimal operation are needed. The goal of this work is to develop thermal management methods for high heat flux applications using two-phase spray cooling techniques. Specifically, thermal management method is developed to achieve higher heat fluxes in the range of 100-1000 W/cm² . Based on the knowledge gaps identified in the literature, the specific objectives developed were to determine the effect of the test surface area scalability on critical heat flux (CHF), to determine the effect of surface modification of the test …

Analysis And Mitigation Of Edge Stresses In Multi-Directional Fiber Reinforced Composite Laminates, Srikanth Sundaresh Ghantae

Dissertations

Edge delamination in composite laminates with adjacent layers oriented at different fiber angles is a major failure mode because of the existence of high interlaminar stresses and poor interlaminar properties. Mitigation of edge stresses poses a challenge even to date. This research provides a detailed analysis and a potential approach to solve this problem in a carbon/epoxy composite laminate. Two extreme laminates of stacking sequence (0_n/90_n)s and (+45_n/-45_n)s subjected to separately applied tensile and thermal loading were considered. These problems have been treated in the literature as a mathematical or bare interface …

Positive Behavior Intervention And Support: An Alternative Approach, Lucy Bridges

Dissertations

The purpose of this study is to examine the effects of PBIS on behavior in relation to the number of office discipline referrals, suspensions, and expulsions. Because of the current school discipline policies, black male students have been overrepresented in the exclusionary practices of office discipline referrals, suspensions, and expulsions. PBIS offers a viable alternative to current school discipline practices.

Agnes Nestor: Labor Leader, Politician, And Social Reformer--A Portrait Of A Leader, Timothy Michael Grivois-Shah

Dissertations

School leadership is about effecting change in education and promoting excellence in teaching and learning. School leaders, however, practice leadership in multiple arenas with diverse stakeholders. Students, local community members, faculty, staff, and each layer of government represent unique and often conflicting interests. Understanding how a leader such as Agnes Nestor resolved conflicts of interests has the potential for helping school leaders access various sources of power to effect change in their milieu.

This study explores the life of Agnes Nestor, a labor leader, politician, and social reformer. Nestor's public life included organizing women workers in Chicago in the early …

Rethinking Nation-Building: A Christian Socio-Ethical And Theo-Political Task For Appropriating The Common Good, Artemus Wlemongar Gaye

Dissertations

nation-building as a coomon good

Multi-Robot Auction Based Coordination, Eisa Hassan Osman

Dissertations

This dissertation studied the coordination problem for a Task Initiator (TI) with multiple ground stations (GSs). Each GS has a team of unmanned aerial vehicles (UAVs) that frequently collected data from a set of unattended ground sensors (UGSs) and delivered it to the source ground station (GS). The GSs made the information available to the TI. This problem formulated into a continuous, time-constrained version of the multi-travelling salesmen problem. A market-based coordination mechanism is presented that uses the concepts of price, revenue, cost, and a sequence of first-price, one-round auctions between the TI and GSs from one side, and double …

Tunable Luminescence And White Light Emission Of Lanthanide-Doped Cawo4 And Casio3 Phosphors Prepared By Pechini And Traditional Sol-Gel Methods, Matthew Anwar Mickens

Dissertations

This study reports the synthesis, characterization, and photoluminescence properties of a calcium tungstate/molybdate (CaWO₄/MoO₄) system, and the synthetic attempts of an agrellite (NaCa₂Si₄O₁₀F) system. The objective is to modify the photoluminescence of both systems by doping with lanthanide/transition metal ions, and to convert them into phosphors with specific applications for light-emitting-diodes (LEDs). CaWO₄ is used as a host matrix to fabricate a white light phosphor. When MoO₄ is added to the system, its excitation range is extended, and its emission profile can be tuned by changing excitation wavelength. …

Modeling And Optimal Mitigation Of Impulsive Low Frequency, Meng Vang

Dissertations

Low-frequency outdoor noise is very common in urban environments and can propagate over long distances. Residents living in the vicinity of a military base and other noisy areas often are annoyed by this noise. Most of the theoretical and experimental work that have been done to study and reduce this type of noise involved the use of barriers and sound proofing the residential houses. The attenuation of acoustic waves propagating above hard surfaces over long distances depends on the shape of the surface. Therefore, the landscape is a factor in combating outdoor noise. In this dissertation, an anti-propagation approach involving …

Understanding Controlled Evaporation Of Microdroplets Towards Scalable Micro/Nano Manufacturing, Taye Dickson Esho

Dissertations

This research investigates the controlled evaporation of microdroplets to the nano scale regime for scalable micro/nano manufacturing. A customized direct write inkjet printing system was utilized to generate monodisperse microdroplets of different fluid types. Two novel approaches were employed to achieve the research objective. The first approach incorporated a convective heat source (i.e. resistive heated ring) to induce controlled heat flux for microdroplet evaporation after ejection from the inkjet system. The temperature of the heated ring was varied to observe reduction of the microdroplet via heat transfer to its lateral periphery. The second approach employed a radiative source (i.e. CO …

Modeling, Simulation, And Optimization Of Diamond Disc Pad Conditioning In Chemical Mechanical Polishing, Emmanuel Ayensu Baisie

Dissertations

Chemical Mechanical Polishing (CMP) is a major manufacturing step extensively used to planarize and smooth silicon wafers upon which semiconductor devices are built. In CMP, the polishing pad surface is glazed by residues as the process progresses. Typically, a diamond disc conditioner is used to dress the pad to regenerate newer pad asperity and a desired surface profile in order to maintain favorable process conditions. Conditioner selection and the determination of the optimal conditioning parameter values to yield a desired pad surface still remain difficult problems. Various analytical process models have been proposed to predict the pad surface profile. However, …

Renewable Energy Integration: Correlating Homeowner Motivations, Casey Jerome Forrest

Dissertations

The purpose of this quantitative correlational study was to explain the relationship between homeowners' preferred leadership style and their motivation to use sustainable energy. This study utilized a quantitative correlational methodology. The researcher developed and administered a questionnaire to collect data from a convenience sample of faculty and staff homeowners from two public institutions in the Piedmont-Triad region of North Carolina. The Leadership Motivation Index Questionnaire (LMIQ) is an 11 question assessment designed to explain potential correlations between the frequency of motivational factors and preferred leadership styles. The LMIQ includes three sections (demographics, motivation, and leadership style) to access what …

Ultra-Low Power Wake Up Receiver For Medical Implant Communications Service Transceiver, James Griggs

Dissertations

The Medical Implant Communications Service (MICS) is an ultra-low power, unlicensed, mobile radio service for transmitting data in support of diagnostic or therapeutic functions associated with implanted medical devices. Medical devices that are implanted in the human body have limited size and battery capacity thus requires ultralow power circuitry. Due to the power consumed by the radio transceiver when the system is active, system level power saving techniques such as “sleep mode” is very essential to achieve “low-power”. A wake up receiver (WuRx) is used to detect wireless traffic directed to a node’s receiver and activate it upon detection, without …

Network Survivability Analysis: Coarse-Graining And Graph-Theoretic Strategies, Teshome Feyessa

Dissertations

Survivability is the ability of a system to continuously deliver essential services despite attacks, failures, or accidents that damage a significant portion of the system. Most of existing survivability measures evaluate global impact of faults on a network by averaging the loss in performance over the whole network. These approaches undermine the fact that a fault is not expected to impact all parts of the network equally. Impacts of some faults are contained in local neighborhoods while others have a global reach. In addition, graph algorithms are often computationally intensive, and even polynomial time algorithms get impractical for a fair …

An Examination Of The Use Of Assessing Capacity To Stimulate Capacity Building With Nonprofit Organizations, Pamela M. Palmer

Dissertations

An in-depth examination of the use of assessing capacity to stimulate capacity building was conducted with member nonprofits of the Guilford Nonprofit Consortium, in Guilford County, North Carolina. The primary research question was "to what extent and in what ways does assessing the capacity of a nonprofit organization help that organization‘s executive director engage in capacity building?" As an academic and practitioner in nonprofit leadership and management, the researcher was interested in exploring the use of assessing capacity prior to implementing capacity building initiatives. The research question prescribes the mixing of research methods and stipulated a connected mixed methods design …

Measurement And Modeling Of Isocyanic Acid (Hnco) In The Troposphere, Anthony Kozeque Cochran

Dissertations

A recent study of biomass fires and some field measurements have revealed that isocyanic acid can reach levels as high as 600 ppbv near fires and up to 200 pptv in ambient air. After the solubility was measured for the first time, it was then possible for any potential human health effects of HNCO to be evaluated. HNCO is highly soluble in the human body given that the physiological pH is 7.4, and there exists an increased risk for atherosclerosis, cataracts, and rheumatoid arthritis via protein carbamylation. Based on preliminary experimental results conducted at a pH of 3.0 ± 0.1 …

Multimodal Human-Machine Interface For Haptic-Controlled Excavators, Benjamin Osafo-Yeboah

Dissertations

Since the 1940s, fluid power has been used effectively in combination with other technologies to provide power in the form of hydraulics or pneumatics for a variety of industries. One such machinery is the excavator. Although the excavator is widely used in industry, numerous design constraints make the interface less intuitive, resulting in long operator training and high cost. Further, traditional excavator-operator interfaces rely mainly on visual and to some extent auditory senses. This often leads to cognitive overload with its negative effect on performance. A haptic-controlled excavator interface has been proposed as an alternative to the traditional excavator interface. …

Molecular Dynamics Modeling Of Scalable Micro/Nano Manufacturing, Ravindra Damodarrao Kaware

Dissertations

In this research, 'Droplet Based Direct Write' micro/nano manufacturing is investigated using a molecular dynamics modeling and simulation approach. The aim of this investigation is characterization of the direct write inkjet printing process to promote optimization for the enhancement of scalability. The study was completed in four phases; nanodroplet evaporation modeling, substrate-nanodroplet interaction modeling, nanodroplet impingement study and nanodroplet-patterned substrate interaction modeling. For the evaporation study, the two typical solvents water and acetone were used. Under this phase, characterization of nanodroplet evaporation was accomplished including evaluation of droplet size variations at different temperatures and time scales. The results of evaporation …