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Experiences Of Black American Millennials: A Qualitative Study Of Internalized And Externalized Coping In The Face Of Racial Trauma, Natalia Angelique Giles

Doctoral Dissertations

The experiences Black Americans have faced when standing against racial trauma have impacted the Black community for generations. Though previous generations faced overt styles of racism throughout the eras of slavery and Jim Crow, the invalidation and discrimination have remained consistent within the experiences of the Black American millennial (BAM) generation. Current experiences BAMs face are a combination of both overt and covert styles of racism, which increase mental exhaustion, reduce motivation, and leave the individual psychologically defenseless. The purpose of this qualitative study was to examine the experiences of BAMs in the face of racial trauma. This qualitative research …

Ratiometric Fluorescent Sensors Based On Non-Covalent Crosslinked Molecular Imprinted Polymers, Yuan Chen

Doctoral Dissertations

This thesis describes a series of optical chemosensors based on FRET between fluorophores on the polymer and the substrate. It involved the preparation of the polymer and nanoparticles for the chemosensor, and the sensing behavior based on the preparation methods.A photophysically inert sensor matrix was prepared by a robust and simple emulsion method. Stannic oxide encapsulated silica nanoparticles with diameters between 25 and 70 nm have been prepared by one-pot reverse-phase emulsion methodology. The constituents and core/shell morphology of the nanoparticles were demonstrated by electron microscopic technology, energy-dispersive X-ray spectroscopy (EDS) and X-ray photoelectron spectroscopy (XPS). X-ray diffraction (XRD) was …

Aspects Of Localizing Quantum Information In Diffeomorphism-Invariant Theories, Adam Dukehart

Doctoral Dissertations

Quantum Field Theory (QFT) is often formulated using local operators, i.e., operators defined at points on a fixed background spacetime. However, General Relativity (GR) requires that observables be fully diffeomorphism invariant. This includes invariance not only under passive diffeomorphisms, which change the coordinate system but also active diffeomorphisms, which imply background independence and a dynamical metric. Localizing such systems and observables in quantum gravity has been a long-standing problem. This dissertation makes progress on two facets of this problem. Part I shows that a typical quantum information paradox using local operators cannot be embedded in a self-consistent, low-energy prescription which …

Learning Trajectories From Human Demonstration Via Time Invariant Dynamical Systems, Paul Gesel

Doctoral Dissertations

Learning from Demonstration (LfD) is a powerful approach that enables users to program robots by simply demonstrating how to perform tasks. Rather than just mimicking the task, the robot should capture key characteristics of the task to adapt and generalize in various situations. Given that there is no explicit objective for each demonstrated task, optimal control methods cannot be directly applied. Two primary paradigms have emerged to overcome the limitation: 1) inverse learning and 2) imitation learning. In this dissertation, I formulate several time-invariant and stable dynamic system-based LfD models that leverage both inverse learning and imitation learning in the …

Exploring Protein Function And Stability: Case Studies On Cryoprotection And Thermal Stability Of Antifreeze Proteins, Enzyme Inhibition Of Sars-Cov-2 Main Protease, And B. Subtilis Protein Stability, Katarina Jovic

Doctoral Dissertations

In this work, I have explored basic questions related to protein structure, function, and stability, which are critical for understanding the fundamental mechanisms of biology. The dissertation is divided into four chapters, which are different topics I have worked on. In Chapters 1 and 2, I will discuss my work on two different antifreeze proteins, in Chapter 3 my work on the main protease from SARS-CoV-2 is presented, while Chapter 4 details the characterization of protein stability of four B. subtilis proteins. While the projects are distinct from one another, they all contribute to deciphering the molecular basis of life …

Understanding The Role Of Impounded Water Bodies In River Network Nutrient Exports In A Dynamic Landscape, Christopher Thomas Whitney

Doctoral Dissertations

Impounded water bodies are a significant component of aquatic networks and various forms have been studied extensively. However, knowledge gaps exist in the research on human-made dams and their reservoirs as well as beaver ponds as both uniquely affect water quality and nutrient exports in different ways. This study fills those knowledge gaps by investigating fluxes of all forms of dissolved nitrogen from small, human-made reservoirs at seasonal timescales. This study found that small reservoirs have a significant effect on nitrogen concentrations but this effect is seasonal and fluxes transported downstream are highly dependent on discharge. Removal of small dams …

Investigating Posttranslational Modifications Of Hsp90 And The Epichaperome In Embryonic Stem Cells, Seth William Mcnutt

Doctoral Dissertations

Heat shock protein 90 (Hsp90) is a highly conserved and essential molecular chaperone in eukaryotes. Through interactions with various co-chaperones, Hsp90 is able to adapt to meet the specific needs of a structurally and functionally diverse, but specific set of clienteles. The diversity of its clients makes it a key regulator of nearly all cellular processes, and it serves as a central hub for many different signaling networks. One of the major functions of the Hsp90 chaperone machinery is in the modulation of protein homeostasis, a protective function often exploited in cancer cells in order to buffer oncogenic mutations and …

Displaying Phenylalanine Ammonia Lyases On Bacillus Subtilis Spore Surface For The Treatment Of Phenylketonuria Through Oral Administration, Guo Wu

Doctoral Dissertations

Bacillus subtilis spores are formed in response to adverse conditions as a survival mechanism. These spores are in a dormant state and do not require any nutrients. Their DNA is wrapped with self-assembled multilayers of protective proteins. These spores are highly resistant to various harsh conditions. B. subtilis spores serve as a well-characterized model for studying endospore formation and have been developed as a platform system for displaying heterologous proteins of various functions. It has been demonstrated that proteins displayed on the spore surface can enhance their robustness and extend their shelf-life, including enzymes as robust biocatalysts and antigens as …

Potential Vorticity Dynamics Driving Variability In Mean Tidal Currents Flowing Through Bounded Estuarine Channels, Katherine Anne Kirk

Doctoral Dissertations

Tidally induced pressure gradients in sea level drive mean estuarine tidal currents that can have horizontal spatial variability across a bounded channel or inlet. Strong cross-channel gradients in along-channel mean velocity set up extremums in the background potential vorticity that can support instabilities of tidal currents flowing through narrow, bounded estuarine channels and tidal inlets. In addition, conservation of potential vorticity including frictional terms, results in intensification of along-channel tidal currents over shallow lateral shelves. In the first part of this dissertation (Chapter 2), the dispersion equation of barotropic instabilities of tidal currents is analytically solved for simple bathymetry defined …

What Role Do Parents And Acculturation Play In Chinese Female International High School Students’ Mental Health?, You Wu

Doctoral Dissertations

This study examines the challenges and mental health issues faced by Chinese female international students in private Catholic female high schools in the U.S. It explores three main areas: the types of acculturation challenges students face, the impact of these challenges on their mental health, and the role of parental communication in shaping students' and parents' perceptions of acculturation and mental health. Using qualitative methods, the research involved interviews with nine students and five parents from a girls' Catholic high school in California. Data were collected via narrative-inspired Zoom interviews, and analyzed using phenomenological principles, focusing on understanding the lived …

Understanding Principal Influence: A Descriptive-Embedded Case Study Of The Attributes Of Path-Goal Style Of Leadership And Its Influence On Principal's Decision-Making In Response To School Performance Scores, Joshua Sims

Doctoral Dissertations

The purpose of this study was to investigate how Path-Goal leadership styles impact the decision-making process of school principals in response to school performance scores. Using purposive sampling, the researcher selected participants from public high schools in the Northwest Southern region for inclusion in a descriptiveembedded case study, specifically focusing on principals and their instructional leaders. The data collection process encompassed various sources, such as field observations, state-released test data, and semi-structured one-on-one interviews with principals and instructional leaders. The theoretical framework underpinning this study was the Path-Goal theory of leadership, which posits four distinct leadership styles: Directive, Supportive, Participative, …

Development And Validation Of An Instrument To Evaluate Social Media Engagement With Millennial Alumni, Megan Robinson Smith

Doctoral Dissertations

Higher education leaders may need assistance creating engaging social media content for alumni. Research questions for the current study included: What values, attitudes, and behavior variables are associated with engaging millennials? What motivations and gratification variables are associated with engaging millennials on social media? How would university leaders use the instrument to assess engagement with millennial alumni via social media through an understanding of millennial values, attitudes, behaviors, motivations, and gratifications variables? Both generation and uses and gratification theories provided the frameworks for developing the instrument. The study used the modified Delphi method to create the instrument. Building the instrument …

Modeling And Analysis Of The Selective Lightning Strike Phenomenon At Locations In A Chemical Manufacturing Plant, Terver Maor

Doctoral Dissertations

This research was motivated by the overly simplified claims, from a previous study, that attempted to explain the cause of the reportedly repeated lightning strikes at certain locations in the chemical manufacturing plant. The findings, without any model, claimed that the electronic monitoring and control devices’ fire damage occurred, due to the raised electrical ground potential during lightning strikes. It proceeded that the raised electrical ground potential caused a power flow reversal, which exceeded the ratings of the affected electronic control modules, damaging them. This claim is inconsistent with published research work in the failure mechanisms of industrial control systems, …

Atomistic-Informed And Machine Learning-Assisted Crystal Plasticity Modeling For Materials Interface, Ibrahim Altarabsheh

Doctoral Dissertations

This dissertation presents a comprehensive study that addresses two critical challenges in the field of computational materials science and engineering from nano- to mesoscale. First, to overcome the well-acknowledged length scale limitation associated with atomistic simulations, a novel two-step approach is introduced for a probabilistic prediction of stress-strain curves in terms of material volume. The method combines Molecular Dynamics (MD) simulations and a multioutput Gaussian process (MOGP) with Bayesian analysis to model stress-strain behavior and predict stress and strain values. The model effectively captures the intricate three-stage curve shape exhibited in stress-strain plots, discerning key points such as yielding, hardening, …

Finding Synergy: Improving Biopesticide Efficacy For Disease Control Through Co-Application With The Natural Product Chitosan, Liza M. Degenring

Doctoral Dissertations

Annual crop losses caused by plant diseases are estimated worldwide at 220 billion US dollars. Conventional fungicides are the primary means to control these diseases, however there are growing concerns over human health, effects on non-target species, and environmental contamination. Furthermore, many plant pathogens have developed fungicide resistance due to overexposure to chemicals with single modes of action. There is a worldwide trend to explore alternative tools to reduce the use of synthetic fungicides while continuing to reduce plant disease. Among these control strategies are the use of antagonistic microorganisms (biopesticides) and naturally occurring compounds that have fungicidal activity. Chitosan …

Hypergroups From Fusion Subcategories And Their Integral Forms, Alice A. Hempel

Doctoral Dissertations

Fusion categories are generalizations of finite groups and are found in areas of mathematics that involve algebraic structures. They are also found in other fields, such as theoretical physics (quasiparticles) and computer science (quantum computing). Their ubiquitousness in these areas make them useful subjects to study.

As a generalization of finite groups, fusion category theory contains many analogs to the objects and constructions found in group theory. But an analog to an essential object of study in group theory, that of the quotient group, is relatively unexplored. In this work, we introduce quotients of braided fusion categories as certain hypergroups …

Studies In Computational Plasma Physics, John Donaghy

Doctoral Dissertations

The scope of this work spans computational plasma simulation and modeling using state-of-the-art numerical and machine learning methods. The numerical work discussed involves performance and correctness modeling of two massively scalable heterogenous code bases. A gyrokinetic code used to simulate a plasma subjected to a strong magnetic guiding field and a particle-in-cell code used for simulating high energy density plasmas in a number of scenarios undergoing magnetic reconnection. Both code bases are capable of being distributed to cpu or gpu based compute nodes.

The gyrokinetic code was used to study microinstabilities and turbulence in the edge region of a magnetically …

Knowing Me, Knowing You: The Role Of Personal Intelligence In Romantic Relationship Conflict Communication, Victoria Bryan

Doctoral Dissertations

People bring to their relationships a variety of personality traits that guide their interactions with others. However, an individual’s unique set of needs, preferences and skills can make conflict a near-inevitable part of most relationships. Personal intelligence is a promising new construct with implications for how couples communicate during conflict. Named in parallel with spatial, social, and similar intelligences, personal intelligence involves the ability to reason about the personality of oneself and others. People high in personal intelligence show an increased capacity to recognize the motives that guide other’s behavior, which they use to adjust how they approach their interpersonal …

Conditionally Automated Vehicles As A Safe And Productive Workspace, Nabil Al Nahin Ch

Doctoral Dissertations

Future automated vehicles will allow drivers to reclaim some of their driving time and perform personal or work-related activities while the car is in automated driving mode. However, traditional automotive user interfaces (UIs) are not designed to support such activities. For a vehicle to be considered a safe and productive workspace, we will have to explore how drivers can interact with emerging UIs in a car to engage in complex non-driving related tasks (NDRTs) and safely resume driving when needed. In the second chapter of this thesis, we present a user-elicitation study where we investigate how drivers would want to …

Acoustic Waveform Optimization For Three-Dimensional Object Geometries, Justin Ng

Doctoral Dissertations

In recent years, deep learning (DL) has become an increasingly important tool for many different types of classification, identification, and related problems including inverse radar and sonar applications. This thesis studies the degree to which radar and sonar systems may be optimized for DL algorithms in a theoretical setting. Most of the current existing literature found on using DL involve solving a full inverse scattering problem (ISP), that is to determine the properties and/or geometry of the scatter from nearly complete measurements of the scattered field. Methods suitable for use in two-dimensional space have been proposed and demonstrated with varying …

Non-Equilibrium Multiphase Particle Morphologies: Synthesis, Functionalization & Modeling, Yung-Chun Lin

Doctoral Dissertations

Waterborne technology highlights the advantage of using water as the dispersed media to replace the need for organic solvents. Emulsion polymerization is one of the most important techniques to produce functional polymer colloids of industrial importance. Besides the choice of monomers in the reaction, composite particle morphology significantly influences the mechanical properties of the materials in the applications of architectural coatings, adhesives, printing inks, and impact resistant plastics. Generally, emulsion polymerization produces spherical particles in the presence of water due to surface tension forces. In seeded emulsion polymerization, composite particles containing two incompatible phases can lead to various anomalous structures …

Black Phosphorus/Carbon Nitride Heterojunctions For Solar Fuel Generation, Nicholas Pollak

Doctoral Dissertations

Solar fuel generation has garnered attention in recent years as a renewable source for syngas (hydrogen and carbon monoxide) evolution. Difficulty in designing one-pot systems that can generate tunable ratios of hydrogen and carbon monoxide gases has persisted. In this thesis, a photocatalytic system for the generation of syngas under simulated solar irradiance is described that satisfies these challenges using black phosphorus (BP) and carbon nitride loaded with Co2+ active sites (Co@C3N4) to form a heterojunction. This thesis will present the ability to tune the syngas ratio by controlling the %wt of BP in the heterojunction. The oxidative power of …

Effects Of Dietary Cation Anion Difference And Nicotinic Acid Supplementation On Jersey Prepartum Cows, Colostrum, And Calves And Creating A Model For The Prediction Of Colostrum Quality And Quantity In Jersey Cows From Performance In The Previous Lactation And Environmental Changes, Tess Catherine Stahl

Doctoral Dissertations

Two experiments were conducted. The objectives of the first experiment were to evaluate colostrum quantity, quality, nutrient composition, and bioactive compounds from Jersey cows fed two levels of dietary cation anion difference (DCAD; –40 or –80 mEq/kg) with or without 23 g/d unprotected nicotinic acid (NA) and its effect on cow and calf performance. The hypothesis is that both DCAD and nicotinic acid could improve colostrum quality, increase quantity and bioactive compound concentration, and improve calf intestinal development. Previous research indicated the benefits of supplementing NA in prepartum Holsteins towards improved colostrum quality, as well as enhanced feed efficiency (FE) …

Affecting Martensitic Transformation And Residual Stress Development Through Stress Superposition And Incremental Forming, Elizabeth Marie Mamros

Doctoral Dissertations

Stress superposition is defined as the incorporation of additional stresses into an existing manufacturing process during a single operation. In this thesis, experiments, simulations, and modeling of stress superposition in sheet metal deformation were investigated. Stress superposition can be used in manufacturing to reduce forming forces, increase material formability, and tailor the final part properties of products according to their intended applications, creating so-called functionally graded materials. Austenitic stainless steels (SS) were the focus due to their susceptibility to strain-induced phase transformation from austenite to martensite based on the stress state applied. In the first chapter, a novel cruciform specimen …

Robust Behavior Cloning For Multi-Step Sequential Task Learning By Robots, Mostafa Abdallah Mohamed Hussein

Doctoral Dissertations

This research is about learning high-level policies of multi-step sequential (MSS) tasks – such as activities of daily living – from demonstrations in a sample efficient manner. This research does not assume access to a simulator or an expert to provide more demonstrations. Learning a task policy in such a setting using state-of-the-art end-to-end approaches is sample inefficient due to a reliance on deep learning frameworks, which are known to require a large amount of data. Besides that, most imitation learning frameworks in robotics assume that a domain expert’s demonstration always contains a correct way of doing the task. Despite …

The Ecology, Biology, And Biogeography Of The Invasive Red Alga Dasysiphonia Japonica (Rhodophyta: Ceramiales) In The Southern Gulf Of Maine, Brandon Scott O'Brien

Doctoral Dissertations

Many coastal ecosystems are under threat from the combined pressures of climate change and introduced species. The Gulf of Maine is one such region under siege, being one of the fastest warming bodies of water in the world and being host to a variety of introduced species. In this dissertation, I investigate the invasion potential of the invasive red alga Dasysiphonia japonica in the Gulf of Maine and beyond through a combination of field, laboratory, and modeling studies. Despite being a recent introduction, Dasysiphonia has rapidly spread along the New England coastline. In areas where it has become established, Dasysiphonia …

Physiological And Biochemical Analysis Of The Nitrogen Metabolism And Lead Treatment In Hybrid Poplar Clone Nm6 (Populus Nigra L. X P. Maximowiczii A. Henry), Medini Weerasinghe

Doctoral Dissertations

ABSTRACTThe first objective of my Ph.D. research was focused on understanding the reasoning for changes observed in the physiology and metabolism of the poplar plants in response to foliar application of nitrogen. Increased use of nitrogen in the soil in agriculture, in the form of nitrogen fertilizers, has helped to promote high-yield agriculture over the past decades. However, a large fraction of nitrogen applied to croplands in the form of fertilizer and manure ends up entering the freshwater system causing degradation of the water quality and eutrophication of groundwater, rivers, lakes, and coastal and marine ecosystems. Chemical fertilization is also …

An Analysis Of Fine-Scale Structure Within Ion Upwelling Processes, Niharika Godbole

Doctoral Dissertations

This dissertation showcases the projects that I have been involved with since I joined the Magnetosphere-Ionosphere Research Laboratory (MIRL) at the University of New Hampshire (UNH) in August 2017, under the guidance of my research advisor, Marc Lessard. Chapters 1, 2, and 3 of this dissertation are intended to provide the science background necessary to discuss the research projects presented in Chapters 4, 5, and 6 respectively.

The system that this dissertation addresses is complex and interconnected. In the most general sense, the Sun interacts with the Earth through the highly conductive, magnetized plasma that it emits, which directly shapes …

Essays In Public Policy And Mental Health, Bryce Stanley

Doctoral Dissertations

In this work I examine how various public policies can influence mental health outcomes. As mental health issues can be created or exacerbated by numerous different factors, many types of public policy can have mental health implications, perhaps not always intended by policy makers. In many cases, these implications are ambiguous from a theoretical level, making empirical research in the area important. Specifically, I model how labor market policies with minimum wages and Earned Income Tax Credit, health policy with the Dependent Coverage Mandate aspect of the Affordable Care Act, and social policy with recreational cannabis laws impact mental health …

Building An Open Source Toolkit For Integrating Multiple Datasets For Seafloor Characterization And Habitat Mapping, Massimo Di Stefano

Doctoral Dissertations

Characterizing and mapping the seafloor and its features requires collecting and analyzing datasets of varied types and scales. Remotely-sensed data can increase our understanding of seafloor processes by providing insight into seabed geomorphology, substrate characteristics, etc., over large areas. Collecting direct observations or physical samples of the seafloor, also known as ground-truth data, holds the key to interpreting and validating remote sensing data. In this thesis, the case is made that by concurrently analyzing some or all of these datasets, knowledge about seafloor processes is gained more efficiently and I develop tools for seafloor habitat mapping.

In Paper I, I …