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Novel Multiphysics Phenomena In A New Generation Of Energy Storage And Conversion Devices, Arpan Kundu

Open Access Dissertations

The swelling demand for storing and using energy at diverse scales has stimulated the exploration of novel materials and design strategies applicable to energy storage systems. The most popular electrochemical energy storage systems are batteries, fuel cells and capacitors. Supercapacitors, also known as ultracapacitors, or electrochemical capacitors have emerged to be particularly promising. Besides exhibiting high cycle life, they combine the best attributes of capacitors (high power density) and batteries (high energy storage density). Consequently, they are expected to be in high demand for applications requiring peak power such as hybrid electric vehicles and uninterruptible power supplies (UPS). This dissertation …

British Essentialism In Eighteenth-Century British Travel Literature Of The West Indies And North America, Stephanie Matos-Ayala

Open Access Dissertations

This dissertation explores issues of representation and cultural negotiation by examining how the white colonial other was depicted in eighteenth-century travel literature, specifically Janet Schaw’s Journal of a Lady of Quality written during the years 1774 to 1776. Travel narratives and histories speak to many different topics, yet they reveal the most about eighteenth-century British ways of thinking about race and national identity, more so than about the various peoples and cultures they seek to describe. I argue that this literature reveals a hierarchy based on the absorption and consumption of British practices and goods by the colonial subject. Neither …

Signal Processing For Caching Networks And Non-Volatile Memories, Tianqiong Luo

Open Access Dissertations

The recent information explosion has created a pressing need for faster and more reliable data storage and transmission schemes. This thesis focuses on two systems: caching networks and non-volatile storage systems. It proposes network protocols to improve the efficiency of information delivery and signal processing schemes to reduce errors at the physical layer as well. This thesis first investigates caching and delivery strategies for content delivery networks. Caching has been investigated as a useful technique to reduce the network burden by prefetching some contents during o˙-peak hours. Coded caching [1] proposed by Maddah-Ali and Niesen is the foundation of our …

Global Analyses Of Protein Complex Localization, Oligomerization, Composition, And Dynamics Using Quantitative Mass Spectrometry, Zachary M. Mcbride

Open Access Dissertations

Proteins perform essential processes in plant cells such as photosynthesis, protein translation, maintenance of metabolic flux, and signal transduction. Many of these functions could never be achieved using individual proteins. Consequently, many proteins oligomerize to form complexes that act as tunable molecular machines that perform work and transmit information. Cells contain thousands of protein complexes, yet the composition of the vast majority remain unknown. Previous high throughput approaches to identify protein interactions have relied on binary interactions or tagging individual proteins for purification. A new set of label free correlation profiling methods were developed that extracted native protein from Arabidopsis …

Effects Of Anaerobic Digestion On Nutrient Conversion And Digestate Land Application On Nutrient Losses, Igor Moreira Lopes

Open Access Dissertations

The adoption of anaerobic digestion (AD) at agricultural systems as an alternative technology for waste management and renewable energy production has raised the concern regarding the value of AD digestate as fertilizer and the environmental impact of the digestate land-application. This Ph.D. research project aimed to gain new knowledge into the impact of AD on digestate characteristics in comparison with the digester feedstock, and the impact of digestate as fertilizer on water quality in comparison with inorganic fertilizer and raw manure. The project was divided into four different studies: a digestate characterization study and three digestate application studies. The digestate …

The Effectiveness Of Visual Input Enhancement Across Multiple Proficiency Levels On The Noticing And L2 Development Of German Vocabulary And Reading, Christopher La Cross

Open Access Dissertations

The present study investigates the effectiveness of visual input enhancement across multiple proficiency levels on the noticing and L2 development of German vocabulary and reading. The study addresses several methodological issues in the extant literature and uses a complex organization to investigate possible differences in the effectiveness of visual input enhancement, a frequently used technique in L2 reading, across multiple proficiency levels in a typical L2 classroom setting at the university level. The study reveals that little to no differences exist across proficiency level and text level and that visual input enhancement, as is so often employed, has extremely limited …

Investigations Of The Electrical, Vibrational And Optical Properties Of Graphene-Based Materials, Ting-Fung Chung

Open Access Dissertations

Graphene and its hybrids have stimulated significant scientific interest owing to their unique properties and technological importance. In this dissertation, we investigate the vibrational, electrical, and optical properties of these remarkable low-dimensional materials by multiple methods including optical measurements (Raman spectroscopy and photoelectrical measurements) and electrical transport measurements (such as the temperature and magnetic field dependence studies). The materials studied have been synthesized or fabricated by methods including chemical vapor deposition (CVD) as well as mechanical exfoliation and transfer.

Twisted bilayer graphene (tBLG) exhibits distinct physical properties compared to monolayer and Bernal-stacked bilayer graphene counterparts. In particular, the electronic structures …

Part I: Polyrotaxanes As Mri Contrast Agents And Npc Therapeutics. Part Ii: Development Of An Analytic-Directed Synthesis System, Bradley P. Loren

Open Access Dissertations

The work described in this dissertation is separated into two parts. Part I describes the development of cyclodextrin-based polyrotaxanes (PRs) as both MRI contrast agents and as potential therapeutics for Niemann-Pick Type C (NPC) disease. Polyrotaxanes are a class of supramolecular materials which are constructed through the non-covalent threading of macrocyclic molecules onto a polymer core that are retained by the covalent attachment of bulky molecules to the ends of the polymer as end-caps. This unique architecture provides a rigid and rod-like morphology that imparts attractive biological and mechanical properties compared to other nanomaterials used in biological applications. In our …

Interplay Of Endogenous And Exogenous Biochemical Species On Neuropathic Pain After Spinal Cord Injury, Breanne Suzanne Muratori Butler

Open Access Dissertations

Neuropathic pain after spinal cord injury (SCI) presents a complex clinical challenge, affecting millions with no satisfactory treatment options currently available. Much of the recent research focuses on a wide variety of endogenous mechanisms that can contribute to pain, but have yet to produce positive results in clinical studies. This dissertation focuses on the role of a highly reactive and toxic aldehyde, acrolein, in initiating, instigating, and perpetuating neuropathic pain after spinal cord injury. Acrolein is shown to mimic damage caused by an injury, in the absence of mechanical trauma. Additionally, removing it using acrolein scavengers can mitigate neuropathic pain-like …

Plant Cell Wall Modification During Tomato Processing And Its Effects On The Physical And Rheological Properties Of End Products, Xing Fei

Open Access Dissertations

Understanding the relationship between structure and functional properties in plant-cell-wall-derived foods has become a growing interest to both academia and industry. Tomato is one of the most cultivated vegetable crops and mostly is consumed as processed products in the form of suspensions. Rheological properties of tomato product, a key functional attribute, depends on both the serum and particle phases of these products. Although recent studies have suggested that the particle phase is the dominant factor, the relationship between fundamental particle properties and the bulk rheology of the suspension is still unclear. This research systematically evaluated the contributions of soluble pectin …

Understanding Macroscale Patterns And Processes Of Invasion, Gabriela Nunez-Mir

Open Access Dissertations

The increasing rate of biological invasions and their impacts are one of the major threats in the Anthropocene. However, certain knowledge gaps remain in our understanding of patterns and processes of invasion, despite an extensive body of research dedicated to this phenomenon. Highly-debated topics in invasion ecology could benefit from a macrosystems perspective. Studies performed at the macroscale are able to capture the effect of global-level processes that drive invasions, detect patterns that transcend taxonomic and geographic boundaries, and minimize biases stemming from the specificity of studies performed at more localized scales. Here, I aim to provide novel insights into …

Modeling And Simulation Of Multiphase Flow Between Rotating And Stationary Disks, Irsha Pardeshi

Open Access Dissertations

The Clutch in an automotive vehicle transfers power from the engine to the wheels with the speed and torque controlled by a gearbox. To accommodate different speeds and loads, different gear ratios are needed, and the clutch disengages and engages every time those ratios are changed. Since heat is generated when disengaged and when suddenly engaging, lubricating oil is pumped throughout the clutch to cool and to reduce friction. When the clutch is disengaged, drag torque is generated. Drag torque is due to the viscous force from the relative motion between the friction (rotating) disk and the separator (stationary) disk. …

A Molecular Perspective For The Understanding Of Polymer‒Drug Interactions, Laura Isabel Mosquera Giraldo

Open Access Dissertations

Polymers are often used to stabilize amorphous drug formulations enabling the maintenance of high drug supersaturations. However, the molecular mechanism of stabilization is unclear, making the rational design of new polymers challenging. This research has focused on understanding the effectiveness of polymers to inhibit drug crystallization using experimental and computational modeling approaches. This thesis has six sections. The first section reviews the pharmaceutical significance of amorphous solid dispersions. The second section describes a study to evaluate the phase behavior of supersaturated drug solutions of telaprevir, a compound that undergoes glass-liquid phase separation when the amorphous solubility is exceeded. The third …

A Measure Of Human-Integrated System Performance Under Time-Varying Circumstances, Nguyen-Vang-Phuc Nguyen

Open Access Dissertations

There are many methods to evaluate a system from given options in discrete or fixed situations (‘circumstance’). However, most systems are operated under time-varying circumstances and it’s not known how to evaluate the best system design when the operator in that system moves between time varying circumstances. In this dissertation, an adaptability model has been formalized using symbolic notion, which is based on learning curve theory and the adaptability measures are proposed. In the first study (‘the demonstration study’), the measures proved that they could be calculated and the learning curves could be plotted in continuous varying-circumstances. In the second …

Nanoparticles With High Drug Loading And Circulation Stability For Systemic Delivery Of Anticancer Drugs, Joonyoung Park

Open Access Dissertations

Nanoparticles have been pursued as a promising strategy to improve the safety and therapeutic efficacy of systemic chemotherapy, but clinical translation of nanoparticle drug carriers has been slow. Several reasons account for the tedious progress. From the formulation perspective, drug loading efficiency and circulation stability remain to be improved: Low drug loading increases the amount of co-delivered carrier materials, imposing biological burdens to patients. Poor circulation stability compromises the pharmacokinetic benefits of nanoparticles. To develop nanoparticles with high drug loading efficiency and circulation stability, albumin-coated nanocrystal (“Abxtal”) formulation of hydrophobic anti-cancer drugs was developed. Abxtal consists of drug nanocrystals and …

Human Rights Treaty Commitment And Compliance: A Machine Learning-Based Causal Inference Approach, Dan Sin Nguyen Vo

Open Access Dissertations

Why do states ratify international human rights treaties? How much do human rights treaties influence state behaviors directly and indirectly? Why are some human rights treaty monitoring procedures more effective than others? What are the most predictively and causally important factors that can reduce and prevent state repression and human rights violations? This dissertation provide answers to these keys causal questions in political science research, using a novel approach that combines machine learning and the structural causal model framework. The four research questions are arranged in a chronological order that refects the causal process relating to international human rights treaties, …

Lightweight Programming Abstractions For Increased Safety And Performance, Leo Osvald

Open Access Dissertations

In high-level programming languages, programmers do not need to worry about certain implementation details that compilers or interpreters do behind the scenes. However, this oftentimes results in some loss; in the former case, it is the inability to precisely communicate programmer’s intentions to a compiler that compromises safety, and in the latter case, it is the loss of performance because an interpreter needs to do extra work at runtime. Modern languages tend to address this problem differently, albeit rarely without serious limitations. In this dissertation, we develop lightweight programming abstractions whose implementation is practical in multi-paradigm high-level languages such as …

Optical Signal Processing For Manipulating And Characterizing Time-Frequency Entangled Photons., Ogaga D. Odele

Open Access Dissertations

Time-frequency entangled photons ("biphotons") exhibit joint spectral and temporal correlations that are unattainable with classical light. Besides being deployed for tests of quantum nonlocality, these photonic states are desirable for a unique range of applications that can significantly impact communications and computation. In this dissertation, we describe novel schemes based on spectral and temporal domain processing for manipulating and characterizing broadband biphotons. Implementing frequency-dependent filters, first, we present and demonstrate a technique for controlling the relative delay between a pair of entangled photons, relying on pump frequency tuning and the quantum concept of nonlocal dispersion cancellation. Next, we demonstrate near-field …

Rational Design Of Pharmaceutical Salt Formulations By Understanding The Mechanism Of Disproportionation, Mitulkumar A. Patel

Open Access Dissertations

Salt forms of the active pharmaceutical ingredient (API) are commonly encountered in the pharmaceutical industry. About half of marketed pharmaceutical products contain the salt form of the API. Salt disproportionation, where the salt converts to the free form, is an important concern for pharmaceutical products containing the salt form of a drug. This is because conversion of the salt to the free form decreases the solubility and/or alters the reactivity, potentially resulting in a decrease in product quality. However, many of the factors dictating the tendency of a given salt to undergo disproportionation remain to be elucidated. In particular, the …

Minimal Area Surfaces Corresponding To Wilson Loops In Gauge Theories, Changyu Huang

Open Access Dissertations

In this dissertation, we study the properties of Wilson loops in strongly coupled gauge theories by using one of the most important results of the AdS/CFT correspondence, namely, that the expectation value of the Wilson loop operator is related to the area of the minimal area surface ending on the Wilson loop. In particular, we concentrate on the main example of AdS/CFT correspondence which is the duality between the N = 4 Super Yang-Mills (SYM) theory in 4 dimensions and type IIB string theory in AdS5 × S5 space. In this case, the minimal area surfaces live in Anti de …

Understanding The Molecular Mechanism Of Arsenic Tolerance And Accumulation In Pteris Vittata, Chao Cai

Open Access Dissertations

Arsenic is a toxic metalloid that is naturally occurring and widely distributed. The consumption of arsenic-contaminated food and water is threatening the health of millions of people in the world. The fern Pteris vittata is unusual in its ability to tolerate and hyperaccumulate exceptionally high concentrations of arsenic in its fronds. How P. vittata tolerates and accumulates arsenic is fundamentally different from that in angiosperms; however, the molecular mechanism underlying this trait in P. vittata is not well-defined. Because the haploid phase of the fern (the gametophyte) is morphologically simple, easy to grow and also tolerates and hyperaccumulates arsenic, the …

Computational Learning For Hand Pose Estimation, Chiho Choi

Open Access Dissertations

Rapid advances in human–computer interaction interfaces have been promising a realistic environment for gaming and entertainment in the last few years. However, the use of traditional input devices such as trackballs, keyboards, or joysticks has been a bottleneck for natural interactions between a human and computer as two points of freedom of these devices cannot suitably emulate the interactions in a three-dimensional space. Consequently, a comprehensive hand tracking technology is expected as a smart and intuitive option to these input tools to enhance virtual and augmented reality experiences. In addition, the recent emergence of low-cost depth sensing cameras has led …

Development Of Tandem Mass Spectrometric Methods And Instrumentation For The Structural Elucidation Of Unknown Drug Metabolites Based On Ion/Molecule Reactions, John Yuk Kong

Open Access Dissertations

Mass spectrometry has proven to be an invaluable tool for the analysis of compounds in complex mixtures. High resolution mass spectrometry provides elemental compositions of compounds. Tandem mass spectrometry (MSn) utilizing collision-activated dissociation (CAD) or ion/molecule reactions has become a powerful technique for structural elucidation of unknown compounds. Further, the coupling of MSn with a separation technique, such as high performance liquid chromatography (HPLC), enables the analysis of trace level analytes in complex mixtures. This dissertation focuses on the development of MSn methodologies and instrumentation for the structural elucidation of unknown compounds. While CAD is the most common MSn technique …

When Perceptions Aren't Shared And Relationships Aren't Parallel: The Curious Case Of Family Supportive Supervisor Behaviors (Fssb), Matthew B. Perrigino

Open Access Dissertations

Perspectives which extend study of work-nonwork interface from the individual level of analysis to the workgroup level are dominated by homologous assumptions. These homologous assumptions are characterized by (a) shared perceptions within workgroups and (b) parallel relationships similar in direction and magnitude across levels. I return to the basics of multilevel theory to consider these assumptions more closely, specifically in the context of family supportive supervisor behaviors (FSSB). Across three chapters, I present the FSSB Separation Framework. Chapter 1 develops theory to explain not only why within-group variation (i.e., a separation in or relative lack of shared perceptions) regarding FSSB …

Electrical, Thermoelectric, And Phase-Coherent Transport In Two-Dimensional Materials, Morteza Kayyalha

Open Access Dissertations

Over the past few years there has been a growing interest in layered two dimensional (2D) materials such as graphene, transition metal dichalcogenides (TMDs), and three dimensional topological insulators (TIs). In this thesis, we experimentally study electrical, thermoelectric, and phase coherent transport in these 2D materials and work on three main projects. First, we investigate the low frequency (f) flicker (also called 1/f) noise of single-layer graphene devices on h-BN along with those on SiO2/Si. We observe that the devices fabricated on h-BN have on average one order of magnitude lower noise amplitude compared with devices fabricated on SiO2/Si despite …

Authoring Organizational Tensions Within The Roman Catholic Church: Women Religious Organize For Themselves, Jessica A. Pauly

Open Access Dissertations

For centuries women religious have faced an uncomfortable tension with the all-male hierarchy of the Roman Catholic Church. This tension is underscored today by the Vatican’s 2008 assessment and subsequent investigation of women religious in the US. Considering this tension-filled context, this study is concerned with the ways in which women religious organize around, alongside, and in some cases against the Church while also supporting the same beliefs and values as the Church. Specifically, this study recognizes NETWORK Lobby for Catholic Social Justice as a unique organizational site operating at the intersection of religion, politics, and authority, and explores how …

Exact Solution Of The Dimer Model On The Square And Triangular Lattice, Dražen Petrovi¢

Open Access Dissertations

In this thesis we give an exact solution of the dimer model on the square and triangular lattice with different boundary conditions. Concretely, we being by discussing Kasteleyn’s contribution to the dimer model studies. We then prove the Pfaÿan Sign Theorem for the dimer model on a triangular lattice embedded in the torus. More specifcally, we prove that the Pfaffan of the Kasteleyn periodic-periodic matrix is negative, while the Pfaÿans of the Kasteleyn periodic-antiperiodic, antiperiodic-periodic, and antiperiodic-antiperiodic matrices are all positive. The proof is based on the Kasteleyn identities and on small weight expansions. Finally, we obtain the full asymptotic …

Quantifying Carbon And Water Dynamics Of Terrestrial Ecosystems At High Temporal And Spatial Resolutions Using Process-Based Biogeochemistry Models And In Situ And Satellite Data, Yang Qu

Open Access Dissertations

To better understand the role of terrestrial ecosystems in the global carbon cycle and their feedbacks to the global climate system, process-based ecosystem models that are used for quantifying net carbon exchanges between the terrestrial biosphere and the atmosphere need to be improved. My research objective is to improve the model from following aspects: 1) Improving parameterization and model structure for carbon and water dynamics, 2) improving regional model simulations at finer spatial resolutions (from 0.5 degree to 0.05 degree or finer), 3) developing faster spin-up algorithms, and 4) evaluating high performance model simulations using fast spin-up technique deployed on …

An Investigation Of Micro-Surface Shaping On The Piston/Cylinder Interface Of Axial Piston Machines, Ashley Busquets

Open Access Dissertations

Presently, axial piston machines of the swash plate type are commonly used in industry due to their many benefits. However, with recent technological advancements in hydraulic hybrid powertrains and displacement-controlled actuation, the application of such machines has been broadened demanding a more cost-effective reliable and efficient, yet versatile machine. The fluid film geometry of the lubricating interfaces is a very complex and sensitive phenomena that must simultaneously fulfill a competing bearing and sealing function. Therefore, the design process of such machines is a difficult process while tightly constrained manufacturing tolerances are essential thereby increasing the initial production costs. Accordingly, virtual …

Morphological Changes Of Neuronal Growth Cones By Intracellular Signaling And Cell Culture Conditions, Yuan Ren

Open Access Dissertations

Proper wiring of neurons is key to the functionality of nervous system. This is achieved by a highly motile structure referred to as the neuronal growth cone located at the tip of axons and dendrites during both development and regeneration. The morphology of growth cone is a product of both intracellular signaling pathways and extracellular factors, and is closely linked with neuronal outgrowth. Studies of how growth cone morphology is changed by key regulatory proteins and by cell culture conditions are therefore important in elucidating the mechanisms of neurite regeneration. In the first part of this thesis, we identified a …