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Development Of A Low Profile, Endoscopic Implant For Long Term Brain Imaging, Benjamin Scott Kemp

Doctoral Dissertations

The increased public awareness of concussion and traumatic brain injury has motivated continued research into the brain, its functions, and especially its response to injury, with a focus on improving the brain’s repair capabilities. However, due to the critical nature of the tissue, it is currently difficult for researchers to acquire high resolution images below the cortex without sacrificing a lab animal. Sacrificing an animal greatly reduces the amount of data that can be obtained from it, making longitudinal studies unappealing or unfeasible because a large number of animals is needed to obtain useful data over multiple time points. Additionally, …

Migration And Electropolymerization Of Methyl Methacrylate In Hardened Cement Paste Via Electrokinetic Treatment, Xi Xie

Doctoral Dissertations

Porous concrete structures are susceptible to the intrusion of chemical species, such as sulfates, chlorides, and carbon dioxide. Many technologies have been developed to repair or rehabilitate damaged concrete. These include cathodic protection, corrosion inhibitor addition, or the use of coatings and sealers. In recent years, a developing technology, electrokinetic nanoparticle treatment, has been shown to reduce concrete porosity, increase strength, promote corrosion resistance, and extend durability. This dissertation was conducted to explore a novel treatment to reduce the porosity of concrete via the application of electrokinetic transportation and electro-initiated polymerization of methyl methacrylate (MMA).

Potassium persulfate (PSP) was used …

Study Of Post-Necking Hardening Identification And Deformation-Induced Surface Roughening Of Metals, Pavlo Knysh

Doctoral Dissertations

This thesis covers topics at two fundamental scales at which plastic deformation is occurring – macroscopic and microscopic.

The first topic is related to the localization of deformation and subsequent necking that happens in metals during deformation, e.g., sheet metal during forming. The open fundamental question is – what happens to the material properties inside of the localized region. The localization process is very challenging to analyze, even using a conventional tension test since several effects such as material hardening as well as effects of strain-rate and temperature are strongly coupled. In this thesis we propose a novel approach that …

Synthesis And Mechanical Properties Of Metallic Multilayers, Tyler Paul Bennett

Doctoral Dissertations

Compositionally modulated alloys and artificial superlattices are thin-layered structures where the layer thickness is on the order of a few 10s of lattice constants. These alloys have been shown to be unusually strong. Their overall thickness can be very large, in this study we have grown these to a thickness of 45 µm by 2.5 cm, in diameter, much greater than the average. We posit the reasons for this strength are that, during deformation, glissile dislocations are pinned at layer boundaries, the presence of image forces, and the formation of Lomer-Cottrell and Hirth dislocation locks. In this thesis we examine …

Invariant Operator Ranges And Similarity Dominance In Banach And Von Neumann Algebras, Ali Zarringhalam

Doctoral Dissertations

\begin{Abstractpage}

\setlength{\baselineskip}{1.5\baselineskip} { Suppose $\mathcal{M}$ is a von Neumann algebra. An \textbf{operator range in

}$\mathcal{M}$ is the range of an operator in $\mathcal{M}$. When

$\mathcal{M}=B\left( H\right) $, the algebra of operators on a Hilbert space

$H$, R. Douglas and C. Foia\c{s} proved that if $S,T\in B\left( H\right) $,

and $T$ is not algebraic, and if $S$ leaves invariant every $T$-invariant

operator range, then $S=f\left( T\right) $ for some entire function $f$.

In the first part of this thesis, we prove versions of this result when $B\left( H\right) $ is replaced with a

factor von Neumann algebra $\mathcal{M}$ and $T$ is …

Seismic Response Of Soil-Foundation Systems On Unsaturated Ground, Seyed Amin Borghei

Doctoral Dissertations

While soils below the groundwater table are fully saturated with water, soils above the groundwater table are partially saturated, as water can rise above the groundwater table through different mechanisms such as capillary rise. In the literature, these soils are commonly referred to as unsaturated soils. The groundwater table fluctuates seasonally; thus, soil moisture profiles may continuously change during a year. Foundations of a considerable portion of structures are placed on the surface or shallowly embedded in soils, which are unsaturated. Properties of soils below the foundations can significantly alter the seismic response of the structures. Since the soil moisture …

Molecular Diet Analyses Of North American Bats, Devon O'Rourke

Doctoral Dissertations

A food web is a model of the feeding relationships among organisms in an environment. The fidelity of this model is limited principally by the ability to detect these interactions. Researchers who study cryptic interactions such as nocturnal insectivory in bats typically rely on fecal samples to identify trophic connections. Historically these diet analyses were limited to morphological inspection of arthropod fragments, however modern metabarcoding techniques have improved the richness and specificity of consumed prey: rather than bats foraging for a few arthropod orders, we observe hundreds of species among guano samples. Animal metabarcoding is not without bias; nevertheless, a …

Advancing The Terrestrial Ecological Unit Inventory Within The White Mountain National Forest Using Lidar, Robert Andrew Colter

Doctoral Dissertations

Forest land managers need ecological classification to assess and describe resource conditions, vegetation conditions, outcomes resulting from various management prescription scenarios, and communicate environmental effects of land management planning alternatives. However, there is a need to incorporate more ecological classification into the land management plans. The U.S. Forest Service’s approach, the Terrestrial Ecological Unit Inventory (TEUI), relies heavily on field data collection and verification of map unit delineations that is time-consuming and costly. Traditional mapping methods far exceed the current financial capacity of the U.S. Forest Service. In order to justify new ecological classification mapping approaches, there needs to be …

Physics And Modeling Of Turbulent Advective Transport In Turbulent Boundary Layers, Juan Carlos Cuevas Bautista

Doctoral Dissertations

\setlength{\baselineskip}{1.5\baselineskip} {Recent studies reveal that at large friction Reynolds number $\delta^+ = u_{\tau}\delta/\nu$ the inertially dominated region of the turbulent boundary layer is composed of large-scale zones of nearly uniform momentum segregated by narrow fissures of concentrated vorticity. Here $u_{\tau} = \sqrt{\tau_{\omega}/\rho}$, where $\tau_{\omega}$ is the shear stress at the wall and $\rho$ the fluid density, $\delta$ is the boundary layer thickness and $\nu$ is the kinematic viscosity of the fluid. The aim of this thesis is better understand the role of this binary structure with respect to the wall-normal transport of momentum and heat in turbulent boundary layers at …

Finding Novel Therapeutics For Blood Cancer Chemotherapy And Immunotherapy, Jin Li

Doctoral Dissertations

This thesis focuses on identification and development of novel small molecule therapeutics for blood cancer. The studies presented herein examine two classes of novel compounds with different mechanisms: tropolones as chemotherapies (Chapters II and III) and phosphoantigens as immunotherapies (Chapters IV-VII).

A library of α-tropolone derivatives was tested for anti-proliferative effects on a panel of hematological malignancies demonstrating preference towards cells of T cell lineage. Through investigating different compounds, some structure activity relationships for compound potency were determined. As a class, the mechanism of action was reliant upon the caspase pathway, p53 regulation, Akt, mTor, and iron. The α-substituted tropolones …

Multifunctional Protein-Lipid Nanoparticles And Hydrogels For Biological And Environmental Applications, Jingwen Ding

Doctoral Dissertations

Archival abstract submitted

Density Matrix Renormalization Group Studies Of Interacting Dipoles In A Zigzag Chain, Niraj Ghimire

Doctoral Dissertations

In this dissertation, we study the many-body effects of dipoles in a quasi-one-dimensional zigzag optical lattice, which we call the zigzag chain. We study this system using the Density Matrix Renormalization Group (DMRG) method, which has established itself as the most powerful numerical method to simulate one-dimensional lattices. For the implementation of DMRG, we have used the open-source package Intelligent Tensor, or simply ITensor. The first part of this research focuses on dipoles polarized in the plane of the zigzag chain by an external electric field with the condition that the dipoles can hop around and interact with their first …

A Novel Approach To Generating Lipid Membranes Of Arbitrary Shape And Composition, Kevin Boyd

Doctoral Dissertations

Biomembranes are essential to cell structure and function. The function of these membranes is dependent not just on their composition of lipids and proteins, but also the distinct morphologies and shapes they present. In recent years, both experiments and simulations have begun to explore the relationship between membrane function and shape, but in this field, there is much to still be explored. The bulk of this work is dedicated to the development and application of techniques to build and study curved membranes in molecular dynamics simulations, using mitochondrial membranes as the primary biological system of study.

Characterization Of Conduction Properties Of Dc Cable Dielectric Materials, Mattewos Tefferi

Doctoral Dissertations

Modern power systems are undergoing a grand transformation towards a wide area transmission network, publicly known as “Smart Grid” and “Super Grid”, for technical and economic advantages. Regional systems have been built-up towards national grids and later interconnected with neighboring countries. High voltage direct current (HVDC) is emerging rapidly as an effective and efficient solution for grid interconnection, island electrification, urban grid decongestion, renewable off-shore wind energy integration.

Despite the emerging opportunities, significant technical challenges persist for HVDC/MVDC technology, namely in DC cabling and accessories, DC breakers and DC diagnosis and monitoring. The major challenge for DC cabling resides in …

The Effects Of Deepwater Horizon Oil, Dispersants, And Environmental Stressors On The Health Of Two Important Gulf Of Mexico Species, Eastern Oysters And Sheepshead Minnows, Lindsay Jasperse

Doctoral Dissertations

The explosion of the Deepwater Horizon oil platform on April 20, 2010 initiated the release of 640 million liters of oil into the Gulf of Mexico (GOM). In efforts to prevent the oiling of coastlines, response officials applied nearly 7.5 million liters of the oil dispersant Corexit. Despite these efforts, oil reached over 2100 km of coastline along the northern GOM, including estuaries that serve as important habitats and nurseries. These estuaries are dynamic ecosystems, with constant fluctuations in salinity and dissolved oxygen. While it is well-established that oil is toxic to marine species, gaps remain in the understanding of …

Development Of Amperometric Microbiosensors For Neurochemical Detection, Chao Tan

Doctoral Dissertations

Abnormal neurochemical signaling is often the underlying cause of brain disorders. Electrochemical microsensors are widely used to monitor neurochemicals with high spatial-temporal resolution. This research aimed to understand and develop highperformance microsensors to detect two types of neurotransmitters: glutamate and dopamine. This work included optimizing multiple parameters used to determine performance of an enzyme-based glutamate microsensor or carbon nanomaterials-based dopamine microsensor. The parameters included sensor surfaces, glutamate oxidase, interferent exclusive layers, storage methods, self-referencing, carbon nanotube coating, polymer exclusive layer applications et al. The developed sensor was also tested in animals.

Tuning key parameters allowed the developed microsensors to exhibit …

Engineering Affinity And Specificity Of Antibodies Targeting Protein Modifications, Dan Li

Doctoral Dissertations

Antibodies targeting protein post-translational modifications (PTMs) are an essential tool in scientific research and clinical investigations. Due to the transient and heterogeneous nature of protein PTMs, high specificity and affinity of PTM-specific antibodies are critical for their sensitive and reproducible detection. However, recent studies have revealed an alarming degree of non-specific binding found in these antibodies, and whether the affinity meets the required detection sensitivity is unclear. To address these challenges, we investigated whether directed evolution could be applied to improve the affinity of a high-specific antibody targeting phospho-threonine 231 of the human microtubule-associated protein tau. We developed a novel …

Synthesis And Characterization Of Transition Metal Oxide/Hydroxide-Based Functional Materials For Environmental And Energy Applications, Junkai He

Doctoral Dissertations

In this thesis, transition metal oxide/hydroxide-based functional nanomaterials with specific structures and properties are developed and characterized for targeting applications in environmental pollution abatement and energy conversion and storage. In the first part, graphene supported Co₃O₄ composite is synthesized in one-step using a facile microwave-assisted method. Graphene serves as the substrate, providing high surface area, good conductivity, and good mechanical and chemical durability. The wide pore size distribution, synergistic effect, and high surface area of the composite are found to contribute to the high performance of lithium-ion batteries. In the second part, we focused on the synthesis …

Paper-Based Point-Of-Care Diagnostic Devices For Urinalysis, Fariba Ghaderinezhad

Doctoral Dissertations

Archival abstract submitted

Towards Provable And Scalable Machine Learning, Jin Lu

Doctoral Dissertations

In the recent decade, machine learning has been substantially developed and has demonstrated great success in various domains such as web search, computer vision, and natural language processing. Despite of its practical success, many of the applications involve solving NP-hard problems based on heuristics. It is challenging to analyze whether a heuristic scheme has any theoretical guarantee. In this dissertation, we show that if a certain structure occurs in sample data, it is possible to solve the related problem with provable guarantees. We propose to employ granular data structure, e.g. sample clusters or features describing an aspect of the sample, …

Dynamic Retirement Financial Planning Model, Qintian Sun

Doctoral Dissertations

We developed a retirement financial planning strategy based on Markov chain modeling of retirement health conditions and Geometric Brownian Motion modeling of asset values. The annual living expenses of a retiree are modeled as basic expenses plus discretionary expenses. Our goal is to solve for the maximum discretionary expenses while healthy, which was obtained using a closed-form solution and quantile optimization technique. The highlight of this model is the use of Kalman Filter for annual recalibration. It allows the model to automatically adjust the suggested amount of discretionary expenses by looking at daily fund values from previous year. After running …

Emotional Manipulation And Cognitive Distraction As Strategy: The Effects Of Verbal Insults On Motivation And Performance In A Competitive Setting, Karen C. P. Mcdermott

Doctoral Dissertations

This study explored the effects of verbally aggressive insults on an opponent’s performance in a competitive setting, i.e. ‘trash talk.’ Bringing together literature from a number of fields, a model was tested which hypothesized that the perception of verbal insults would increase cognitive distraction, elevate levels of emotional arousal, and affect motivation to perform, such that competitive performance would decrease. Anger and shame were posited as the primary manifestations of emotional arousal. The study was operationalized through a video game racing competition as a true experiment with control and verbal insult conditions. Both groups received an auditory treatment delivered by …

Tracking Highly-Maneuvering Targets And Data Fusion From Imm Estimator Tracks, Radu Visina

Doctoral Dissertations

Maneuvering targets are of special interest in remote tracking because of the difficulty in modeling the changes in their dynamic behavior. Sharp maneuvers present challenges. For some targets, such as those moving in a 2D plane, the proposed White Noise Turn Rate (WNTR) model should be included as one or more modes in an Interacting Multiple Model (IMM) estimator. This model is similar to the conventional coordinated-turn (CT) model, also known as the Wiener Process Turn Rate model, but with non-zero mean turn rate process noise, instead of zero-mean turn rate process noise. Such an IMM design, possibly coupled with …

Mechanisms Of Porphyrinoid And Carotenoid Spectral Tuning Revealed With Quantum Chemistry, Matthew J. Guberman-Pfeffer

Doctoral Dissertations

Continued advances in a myriad of biomedical and technological fields require the rational design of molecules or supramolecular architectures with specific photophysical properties. Central to this endeavor is a mechanistic understanding of optical property modulation as a function of molecular structure, conformation, and environment. Natural pigments and protein-pigment complexes constitute a ‘solutions manual’ to challenges in electronic (optical) engineering that has been refined over a few billion years of evolution, and from which design principles can be deduced. In this thesis, unique mechanisms for modulating the optical properties of natural or synthetic porphyrinoid and carotenoid pigments are elucidated with quantum …

Conservation And Divergence Between P22-Like Bacteriophages Coat Protein’S I-Domains And Procapsid-Like Particles, Therese Tripler

Doctoral Dissertations

Conservation and Divergence Between P22-like Bacteriophages Coat Protein’s

I-domains and Procapsid-like Particles

Therese N. Tripler, PhD

University of Connecticut, 2019

P22, CUS-3 and Sf6 are distantly related bacteriophages that belong to the P22-like group based on capsid protein sequence similarity. Despite being distantly related they share important similarities. They form T=7 icosahedral capsids to protect their dsDNA, have capsid proteins that adopt the HK97 fold with an inserted domain, share similar arrangement of their structural genes in their genomes, and infect human enteric pathogens. P22, CUS-3and Sf6 infect Salmonella enterica, Escherichia coli, and Shigella flexneri, …

Fundamental Understanding Of Microstructural Properties Of Electrolyte System For Nox Exhaust Gas Sensing, Khawlah Kharashi

Doctoral Dissertations

The nitrogen oxides (NOx) sensors available on the market are unable to detect minute concentrations of NOx (<10 ppm) and, as a result, they are unable to meet the new US standards, i.e. Tier 3 standards for the period of 2017-2025. As per these standards sensors should be highly sensitive and capable of determining NOx on the order of single parts per million. As compared to gasoline engines, diesel engines have greater efficiency per unit quantity of fuel consumed, but they emit more smog causing NOx.

The three-way catalyst systems in modern diesel engines are ineffective in chemically reducing nitrogen oxides in the presence of excess air. Even though a number of NOx abatement systems have been developed over the years, the after- treatment systems in vehicles require a highly sensitive NOx sensor capable of monitoring low concentrations of NOx in the exhaust gases. The solid state electrochemical sensors, having porous yttria-stabilized zirconia (YSZ), along with dense electrodes, exhibit enhanced NOx sensitivity. Porous electrolytes support gas diffusion, while …

Two And Three-Dimensional Models For Material And Cells Interaction, Nam H. Nguyen

Doctoral Dissertations

Three-dimensional (3D) cell spheroid model has been long considered a better model to mimic in vivo physiology compared to two-dimensional (2D) cell culture model. Traditional 2D cell models provide a simple, convenient and quick technique for drug screening but fail to simulate the complexity and heterogeneity of cells in the in vivo environment. The last few decades have remarked substantial progress toward the advancement of three-dimensional (3D) cell cultures as systems which better mimic cellcell and cell-matrix interaction in the in vivo physiology. Nowadays, 3D cell models have been emerging, not only as an important approach in drug discovery and …

Evaluation Of Carbon Footprint During The Life-Cycle Of Four Different Pipe Materials, Alhossin Alsadi

Doctoral Dissertations

As the world is moving to provide a better and cleaner environment for future generations, there is a critical need to quantify and try to reduce the environmental emission footprints of various industries. The construction industry, which emits a large amount of carbon dioxide (CO₂ ), is one of the targeted industries to decrease these emissions. Underground utility installations, especially in the development of residential communities in urban areas, are one of the largest construction projects across North America and, consequently, one primary source of emissions. Most of the pipelines in the U.S. are rapidly reaching the end of their …

Model-Based And Population-Based Optimization Of Abdominal Aortic Aneurysm Surveillance And Surgery Protocols, Farid Heidarnejad

Doctoral Dissertations

Abdominal aortic aneurysm (AAA) is indicated when the diameter of the abdominal aorta is larger than 30 mm. The primary risk associated with AAA is an increased risk of aortic rupture, which is fatal in 68-90% of cases. Once a patient is diagnosed with AAA, the AAA is monitored via abdominal ultrasound. The rationale for the regular surveillance is that the risk of rupture is low for AAA, less than 55 mm in size, but increases dramatically in diameter larger than 55 mm. Early surgery on patients with smaller AAA diameters (lower risk of rupture) has a higher mortality rate …

Essays In International Corporate Finance, Patrick M. Stanton

Doctoral Dissertations

International corporate finance has greatly expanded with the increased globalization and led to many new research topics. In this dissertation, I examine two distinct international finance topics; (i) determinants of corporate tax inversion and the effects ex-post; and (ii) determinants of for-profit microfinance institutions and financial and social performance.

In Chapter 1, I study corporate tax inversion which is a reorganization by which a domestic firm changes its tax-domicile from the United States to a foreign country with a lower corporate tax rate. In 2014 alone, U.S. public companies valued at over half a trillion dollars announced their intention to …