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Lab-On-A-Chip Thermoelectric And Solid-Phase Immunodetection Of Biochemical Analytes And Extracellular Vesicles: Experimental And Computational Analysis, Saif Mohammad Ishraq Bari

Doctoral Dissertations

Microfluidics is the technology of controlling and manipulating fluids at the microscale. Microfluidic platforms provide precise fluidic control coupled with low sample volume and an increase in the speed of biochemical reactions. Lab-on-a-chip platforms are used for detection and quantification of biochemical analytes, capture, and characterization of various proteins, sensitive analysis of cytokines, and isolation and detection of extracellular vesicles (EVs).

This study focuses on the development of microfluidic and solid-phase capture pin platforms for the detection of cytokines, extracellular vesicles, and cell co-culture. The fabrication processes of the devices, experimental workflows, numerical analysis to identify optimal design parameters, and …

Effects Of Transformational Leadership On Safety Performance In The United States Commercial Trucking Industry, John Francis Mcmahon

Doctoral Dissertations

The purpose of this study was to research whether the leadership styles of safety professionals, supervisory and management leaders of commercial trucking companies, were related to their companies’ safety ratings. The theoretical framework employed in this study was based on the full range leadership model of Avolio and Bass (1991). Sixty-two long-haul commercial truck drivers participated in the study. This quantitative research was a quasi-experimental, correlational study comparing leadership styles with safety indices of trucking companies. The leadership styles were determined using the 45-question Multifactor Leadership Questionnaire (MLQ) Rater Form (Avolio & Bass, 1991) and compared them to the safety …

Methacrylated Collagen And Hnt Composite Hydrogels For Application In Bone Tissue Regeneration, Yue Li

Doctoral Dissertations

Fractures and segmental bone defects are the primary cause of patient morbidity and brings a substantial economic burden to the healthcare system. Bone grafts used for bone injuries, tumors, and other pathologies related to poor fracture healing in the United States cost considerable money each year. The total cost of treating bone defects is about 5 billion US dollars. Autologous bone transplantation is the ideal method for the treatment of bone defects. However, their clinical results are variable and increase postoperative morbidity (especially at the donor site) and surgical costs. To circumvent these limitations, tissue engineering and cell-based therapies have …

Exoprime Technology For Exosomal Mirna Analysis And Identification Of Oxidative Dna Damage-Induced Mirna Regulatory Network In Human Astrocytes, Chukwumaobim Daniel Obiwulu Nwokwu

Doctoral Dissertations

The high lipid content of the brain, coupled with its heavy oxygen dependence and relatively weak antioxidant system, makes it highly susceptible to oxidative DNA damage that contributes to neurodegeneration. This study assesses and compares the neurotoxic effects of proton and photon radiation on mitochondrial function and DNA repair capabilities of human astrocytes. Human astrocytes received either proton (0.5 Gy and 3 Gy), photon (0.5 Gy and 3 Gy), or sham-radiation treatment. The mRNA expression level of the human base-excision repair protein, 8-deoxyguanosine DNA glycosylase 1 (hOGG1) was determined via RT-qPCR. Radiation-induced changes in mitochondrial mass and oxidative activity were …

Characterization Of Commercially Available Conductive Filament And Their Application In Sensors And Actuators, Fraser J. Daniel

Doctoral Dissertations

The primary aim of this study is to contribute to the field of additives that would enable the fabrication of electrical sensors and actuators completely via Material Extrusion based Additive Manufacturing (MEAM). The second aim of the study is to provide the necessary characterization to facilitate the development of applications that predicts electrical part performance. The electrical characterization of two conductive poly-lactic acid (PLA) filaments, namely, c-PLA with carbon black and graphene PLA was performed to study the temperature coefficient of the resistance. Resistivity of carbon black filament was compared to a printed single layer and with that of a …

Prevention Of Organ-Specific Doxorubicin Induced Toxicity Using Physiologically-Based Pharmacokinetic Modeling And Therapeutic Drug Monitoring, Hillary Husband

Doctoral Dissertations

Physiology-based pharmacokinetic models are mathematical models that characterize the behavior of a drug and have compartmental equations that are representative of specific tissues and physiological processes.[1, 2] Doxorubicin is an anthracycline antibiotic that is effective and widely used in anticancer therapy due to its potent cytotoxicity. Unfortunately, with that potency comes cardiotoxic side effects related to cumulative lifetime dose.[3] Specifically, the toxicity is related to the accumulation of the primary metabolite doxorubicinol (DOXol) in the heart.[4] Since the toxicity is organ-specific, the best way to characterize the behavior is through PBPK modeling.[2] Since PBPK models tend to be large systems …

Crossing The Blood-Brain Barrier Using Peptide Vectors For The Treatment Of Traumatic Brain Injury, Jolin P. Rodrigues

Doctoral Dissertations

Here, the BBB-crossing ability of a Trojan horse peptide conjugated to a short therapeutic peptide was evaluated, with the aim to halt the progression of TBI-associated neuronal damage in a mouse experimental model of TBI. An associated study was also conducted to develop a new biosensor to probe hydrogen peroxide – a biomarker of chronic inflammation in the brain. The long-term goal of this study was to assess the regenerative or neuroprotective effect of this potential therapeutic peptide on neural disease pathology, thus expanding the known library of BBB-crossing peptides, and developing new tools for the study of inflammation, such …

Merging Ecology And Earth System Modeling: Biotic And Abiotic Controls Drive Soil Carbon And Nitrogen Cycling In Microbial-Explicit Soil Biogeochemistry Models, Emily Kyker-Snowman

Doctoral Dissertations

Ecological processes drive terrestrial biogeochemistry, yet the incorporation of ecology into the Earth system models that we use to understand and project global change remains. My dissertation focuses on expediting the incorporation of ecology into Earth system models, first by laying out a roadmap from initial assessment of ecological insights to eventual ESM incorporation, and then by demonstrating this roadmap using the example of microbially- controlled carbon and nitrogen cycling in soil. The paradigm around SOM formation and loss has shifted in recent decades away from a focus on the chemically recalcitrant leftovers of litter decomposition and towards a paradigm …

Alkalinity And Buffering In Estuarine, Coastal And Shelf Waters, Christopher Hunt

Doctoral Dissertations

As anthropogenic climate change continues to elevate the amount of carbon dioxide (CO2) in the Earth’s atmosphere, the absorption of a large portion of this CO2 by Earth’s oceans has resulted in a steady decrease in pH. The consequent phenomenon of ocean acidification (OA) is a result of shifts in the carbonate chemistry system of the ocean- a system which can be analytically described by several factors, including total alkalinity (TA). TA in the oceans has been measured for over a century, but analytical and operational constraints have limited these measurements in time and space. Additionally, recent work has highlighted …

Balancing Fracture And Fatigue Performance In Asphalt Pavements: A Hybrid Mechanistic And Statistical Modelling Approach, Danial Mirzaiyanrajeh

Doctoral Dissertations

The asphalt mix design and evaluation approaches are divided into two main categories as empirical and mechanistic-empirical (M-E) methods. The empirical methods are based on empirical observations of in-service pavement performance, and they do not take into account engineering properties or failure criteria. The M-E methods were introduced as a new generation for design and evaluation approaches that consider fundamental mixture properties such as material stiffness to determine the pavement's structural response. However, the need for expensive and time-consuming performance-based laboratory tests and local calibration makes the M-E methods unsuitable for routing design. In addition, during the last few years, …

Laboratory And Computational Mechanics-Based Framework For The Analysis And Design Of Cold Recycled Pavement Layers, Francesco Preti

Doctoral Dissertations

Cold recycling technologies are becoming increasingly popular for rehabilitation of asphalt pavements. These technologies allow construction of new pavement layers with minimal addition of heat and minimal need for transporting the material. In fact, Cold Recycled Mixtures (CRM) can be prepared in mobile plants or directly in place while using up to 100% of the milled material from an existing asphalt pavement (Reclaimed Asphalt Pavement or RAP) and without the need of heating up the aggregates. The products obtained through the use of cold recycling technologies are also commonly called Bituminous Stabilized Materials (BSM). BSM are considered to be partially-bonded …

Learning To Act With Robustness, Reazul Hasan Russel

Doctoral Dissertations

Reinforcement Learning (RL) is learning to act in different situations to maximize a numerical reward signal. The most common approach of formalizing RL is to use the frameworkof optimal control in an inadequately known Markov Decision Process (MDP). Traditional approaches toward solving RL problems build on two common assumptions: i) exploration is allowed for the purpose of learning the MDP model and ii) optimizing for the expected objective is sufficient. These assumptions comfortably hold for many simulated domains like games (e.g. Atari, Go), but are not sufficient for many real-world problems. Consider for example the domain of precision medicine for …

Mechanistic Modelling Framework And Life Cycle Assessment Approach For Pavement Rehabilitation Using Asphalt Concrete Overlays, Katie Eileen Haslett

Doctoral Dissertations

Efficient and effective rehabilitation of existing roadways continues to be a top priority for local, state, and federal agencies to provide safe travel of people and goods. Asphalt concrete (AC) overlays on deteriorated Portland Cement Concrete (PCC) are a popular rehabilitation option to extend the service life of a roadway. However, the combination of load and environmentally induced movements at underlying joint locations can cause high amounts of stresses and strains, leading to the formation of cracks in the AC overlay. Ensuring that a suitable asphalt mixture (cracking resistance) and sufficient overlay structure (thickness) are selected is critical to avoid …

A Comprehensive Study Of The Hardware Trojan And Side-Channel Attacks In Three-Dimensional (3d) Integrated Circuits (Ics), Zhiming Zhang

Doctoral Dissertations

Three-dimensional (3D) integration is emerging as promising techniques for high-performance and low-power integrated circuit (IC, a.k.a. chip) design. As 3D chips require more manufacturing phases than conventional planar ICs, more fabrication foundries are involved in the supply chain of 3D ICs. Due to the globalized semiconductor business model, the extended IC supply chain could incur more security challenges on maintaining the integrity, confidentiality, and reliability of integrated circuits and systems. In this work, we analyze the potential security threats induced by the integration techniques for 3D ICs and propose effective attack detection and mitigation methods. More specifically, we first propose …

Repeatfs: A File System Providing Reproducibility Through Provenance And Automation, Anthony Stephen Westbrook

Doctoral Dissertations

Reproducibility is of central importance to the scientific process. The difficulty of consistently replicating and verifying experimental results is magnified in the era of big data, in which computational analysis often involves complex multi-application pipelines operating on terabytes of data. These processes result in thousands of possible permutations of data preparation steps, software versions, and command-line arguments. Existing reproducibility frameworks are cumbersome and involve redesigning computational methods. To address these issues, we developed two conceptual models and implemented them through RepeatFS, a file system that records, replicates, and verifies computational workflows with no alteration to the original methods. RepeatFS also …

Epileptogenesis In Rodents Leads To Neural System Dysfunction And Loss Of Associative Memory Measured By Auditory Event Related Potentials., Sai Mohan Rudrashetty

Doctoral Dissertations

Epilepsy is a common and disabling neurological condition affecting 1-2% of the world’s population. Individuals suffering from epilepsy are prone to cognitive dysfunctions with detrimental effects in neural processing and memory resulting in decreases in quality of life. An evaluation of inherent neural processes is valuable information to diagnose and clinically assess cognitive function, which could significantly improve the treatment possibilities and thereby the quality of life for epilepsy patients.

An evaluation of cognitive functions during epileptogenesis was performed by experiments using auditory event related potentials (ERP) in rats before and after induction of status epilepticus (SE) using the Lithium-Pilocarpine …

Firm Performance In The Era Of Big Data Analytics: The Effects Of Analytical Human Capital On Firm Capabilities And Performance, Rajiv Dahiya

Doctoral Dissertations

The Big Data phenomenon has revolutionized the way firms do business by providing immense opportunities for valuable business insights from large amounts of data. Big data analytics (BDA) has emerged as one of the top technology investment areas as firms consider it a significant impetus for superior firm performance. However, many firms adopting BDA find it challenging to gain an advantage from their BDA investments. Scholars note the need to further understand the factors and mechanisms of BDA success. Some anecdotal evidence has indicated that a critical barrier to BDA success may be the lack of a necessary workforce with …

Incorporation Of Glycyl-L-Histidyl-L-Lysine (Ghk) With Metalized Halloysites For Tissue Regeneration, Christopher Cameron Miller

Doctoral Dissertations

Human adipose stem cells (hASCs) provide a research tool for regenerative medicine in various capacities. There are major research needs for new therapies for bone-related diseases such as osteoporosis, osteomyelitis, and severe trauma. Human ASCs can self-renew for extended durations outside of the body and provide an ideal platform to study therapeutics for the formation of bone-specific modalities or wound healing applications.

Combining hASCs with nanomaterials is a growing area of research that requires additional studies. Halloysites (HNTs) are hollow aluminosilicate nanotubes with an exterior negative charge and a positively charged lumen. HNTs have demonstrated biocompatibility in cell and animal-based …

In Vivo And In Vitro Expression And Interaction Of The Mediator Kinase Module Subunits During Adipogenesis, Sree Lakshmi Venigalla

Doctoral Dissertations

Selective gene expression is crucial in maintaining the self-renewing and differential potential of stem cells. Especially differentiation process requires a constellation of proteins that regulate expression of genes necessary for differentiation towards a specific lineage. Adipogenesis is a process of formation of mature fat cells from precursor cells that is tightly regulated by a number of transcription factors and their cofactors. Dysregulation in the process often leads to metabolic disorders, which is common due to prevalence of obesity. Mediator is a large, evolutionarily conserved, multi-subunit protein complex that functions as a transcriptional coactivator that modulates gene expression by relaying signals …

Noninvasive Traumatic Brain Injury Therapeutics Effects And Biosensor Implants Optimization In Rodents, Claire Eleanor Jones

Doctoral Dissertations

Traumatic brain injuries (TBI) result in impaired motor and sensory skills, which amplify over time due to the natural immune responses to trauma. Currently, there is no therapeutic on the market to treat the secondary damage from the cascading events caused by neurotrauma. In an experimental treatment method, poly(lactide-co-glycolide)-graft-polyethenimine (PgP) is used as a vector for drug delivery. This previously described method has successfully treated experimental spinal cord injury (SCI) using the nanoparticles for Rolipram (Rm) delivery, a phosphodiesterase inhibitor, to repair damage in a rat model. We proposed to utilize this same treatment to reduce secondary axonal damage after …

Emotional Labor: An Affective-Commitment Perspective, Matthew J. Vosburg

Doctoral Dissertations

The emotional-labor literature asserts that individuals respond to emotion-display requirements, called display rules, with surface and deep acting. However, surface acting, but not deep acting, relates to deleterious occupational-health outcomes. Deep acting, therefore, is a strategy organizations should promote, should they wish to prioritize the well-being of their employees. Unfortunately, little research exists that clarifies the emotional-labor-choice process. The current study used the job demands-resources model and self-determination theory to hypothesize that affective organizational commitment would differentially moderate the relationship between display rules and the methods of emotional labor. To evaluate this study's hypotheses, 320 participants on an online survey …

The Role Of Video Game Play, Gender Roles, And Career Decision Self-Efficacy In Development Of Stem Career Interests & Motivation, Michael Saunders

Doctoral Dissertations

The gender wage gap, disadvantaging working women, continues to grow despite progress toward women’s rights and occupational equity. With the world economy prioritizing growth in technological industries, the underrepresentation of women in science, technology, engineering, and mathematics (STEM) fields perpetuates systemic gender inequity. Further, given traditional social gender roles, women and girls may be less likely than boys and men to pursue STEM careers. Though specialized programs seek to grow the number of girls and young women engaged in STEM-related education and prepare them for the growing demand for STEM laborers, these programs are regional, seasonal, and not widely available …

An Examination Of Organizational Decision-Making: A Case Approach, Olivia Reinecke

Doctoral Dissertations

This applied dissertation offered insights about the scientist-practitioner gap and examined the process of organizational decision making using a real case from a large United States manufacturing company. Historical records of employee work hours were extracted and compiled from several of the company's databases, along with recent plant performance metrics. These archival data were used to evaluate the relationship between the percentage of each plant's population working overtime (i.e., overtime utilization) and each plant’s performance on various manufacturing metrics. This comparison was made using a median split approach, such that the performance of plants with an overtime utilization above the …

Credit Card Security System And Fraud Detection Algorithm, Baker Al-Smadi

Doctoral Dissertations

Credit card fraud is one of the most critical threats affecting individuals and companies worldwide, particularly with the growing number of financial transactions involving credit cards every day. The most common threats are likely to come from database breaches and identity theft. All these threats threat put the security of financial transactions at severe risk and require a fundamental solution.

This dissertation aims to suggest a secure online payment system that significantly improves credit card security. Our system can be particularly resilient to potential cyber-attacks, unauthorized users, man-in-the-middle, and guessing attacks for credit card number generation or illegal financial activities …

Novel Methods For Determining Polymer Content And Polymer Degradation In Asphalt Binder, Roksana Hossain

Doctoral Dissertations

Styrene-butadiene-styrene (SBS) is the most common modifier used in asphalt binder modification because of its superior performance compared to some others that are used. SBS modified asphalt binder increases the rutting resistance and decreases the fatigue and thermal cracking susceptibility of asphalt pavement. However, SBS modified asphalt binder tends to separate and is subjected to thermal degradation during construction and aging degradation during its service life. As a result, quality control of SBS modified asphalt binder is needed, although no standard test method is available to quantify SBS degradation due to aging.

In this study, two methods for quantifying SBS …

Lateral Torsional Buckling Resistance Of Continuous Steel Stringers In Existing Bridges, Dinesha Malky Kuruppuarachchi Kuruppuarachchi Appuhamilage Don

Doctoral Dissertations

Some of the Louisiana’s bridges built in the 1950s and 1960s used two-girder or truss systems, in which floorbeams are carried by main members and the continuous (spliced) stringers are supported by the floorbeams. The main members are either two edge (fascia) girders or trusses. When the flexural capacity of continuous stringers is calculated, the moment gradient factor (Cb) is not accurately calculated considering the lateral torsional buckling (LTB) at the negative moment section. In particular, the bracing effect of the non-composite concrete deck is not accounted for, and as a result, the current practice has underestimated the LTB strength …

Glial Endothelial Brain Cell Co-Cultures For Testing Signaling Response And Delivery Of Novel Materials Across Blood Brain Barrier, Neela Prajapati

Doctoral Dissertations

The brain accounts for 20% of overall energy metabolism in the body though it just comprises 2% of the total body mass but has a limited capacity of storing energy unlike other critical organs in the body such as the heart and liver. This energy along with oxygen and nutrients is supplied by cerebral blood flow (CBF), any interruption of which can cease the brain function within seconds with a potential irreversible neuronal injury, within minutes. Vascular cells along with astrocytes and neurons are a part of a recently developed concept known as the Neurovascular Unit responsible for Neurovascular coupling …

Valorization Of Secondary Agriculture Residues, Narendra Kumar

Doctoral Dissertations

Secondary agriculture residues have the potential to be major contributors as resources for energy and sustainably sourced materials production. Separating secondary agricultural residues, which have already been transported to processing centers, into individual biomass components could convert these wastes into bioproducts. Many types of pretreatments to achieve this separation involve chemicals that are hazardous for the environment. Several deep eutectic solvents (DES) that are biocompatible have been investigated for their ability to deconstruct rice hulls and sugarcane bagasse. Mass yield, enzymatic hydrolysis of the pretreated biomass, fiber analysis, and Fourier transform infrared spectroscopy have confirmed that the DES formic acid:choline …

The Role Of Med31 And Med12 In Directing Adipogenesis Of Human Adult-Derived Mesenchymal Stem Cells, Joseph Straub

Doctoral Dissertations

Selective gene expression is crucial in maintaining the self-renewing and multipotent properties of stem cells. Mediator is a large, evolutionarily conserved, multisubunit protein complex that modulates gene expression by relaying signals from cell type-specific transcription factors to RNA polymerase II. In humans, this complex consists of 30 subunits arranged in four modules: head, middle, tail, and kinase. In our introduction, we show the state of the field of Mediator study with a focus on the critical kinase module. In the following chapters, we used siRNA knockdowns to investigate the roles of the highly-conserved core subunit MED31 and the kinase module …

Multi-Scale Computational Modeling Of Metal/Ceramic Interfaces, Abu Shama Mohammad Miraz

Doctoral Dissertations

Multi-scale atomistic calculations were carried out to understand the interfacial features that dictate the mechanical integrity of the metal/ceramic nanolaminates. As such, first principles density functional theory (DFT) calculations were performed to understand the electronic and atomistic factors governing adhesion and resistance to shear for simple metal/ceramic interfaces, whereas molecular dynamics (MD) simulations were performed to observe the impact of interfacial structures, such as misfit dislocation network geometries and orientation relationships, on interfacial mechanical properties.

For the DFT investigation, we choose metals with different crystal structures, namely - Cu (fcc), Cr (bcc) and Ti (hcp) along with a variety of …