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2020

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Improving Security Of Crypto Wallets In Blockchain Technologies, Hossein Rezaeighaleh Jan 2020

Improving Security Of Crypto Wallets In Blockchain Technologies, Hossein Rezaeighaleh

Electronic Theses and Dissertations, 2020-2023

A big challenge in blockchain and cryptocurrency is securing the private key from potential hackers. Nobody can rollback a transaction made with a stolen key once the network confirms it. The technical solution to protect private keys is the cryptocurrency wallet, software, hardware, or a combination to manage the keys. In this dissertation, we try to investigate the significant challenges in existing cryptocurrency wallets and propose innovative solutions. Firstly, almost all cryptocurrency wallets suffer from the lack of a secure and convenient backup and recovery process. We offer a new cryptographic scheme to securely back up a hardware wallet relying …

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Subsurface Characterization Of Internally Eroded Soils In Karst Using The Cone Penetration Test, Ryan Shamet Jan 2020

Subsurface Characterization Of Internally Eroded Soils In Karst Using The Cone Penetration Test, Ryan Shamet

Electronic Theses and Dissertations, 2020-2023

Sinkholes are a major geohazard with life-threatening consequences when not properly detected and mitigated. Geologic conditions comprised of soluble bedrock (e.g., limestone or other carbonate-based lithologies) overlain by fine-grained sandy and clayey soils, are known internationally as "karst topography" and is generally characterized by such sinkholes, caves, sinking streams, and highly variable groundwater flow conditions. Karst sinkholes, however, are complex geohazards and are difficult to precisely characterize through geotechnical considerations alone. Deterministic methods (e.g., analytical and numerical solutions) may provide for a more robust analysis of internal soil erosion (known as soil raveling) but have limitations for the practical use …

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Multi-Agent Reinforcement Learning For Defensive Escort Teams, Hassam Sheikh Jan 2020

Multi-Agent Reinforcement Learning For Defensive Escort Teams, Hassam Sheikh

Electronic Theses and Dissertations, 2020-2023

Reinforcement learning has been applied to solve several real world challenging problems, from robotics to data center cooling. Similarly, adaption of reinforcement learning for multi-agent systems facilitated applications such as optimal multi-robot control and analysis of social-dilemmas. In this dissertation, we show that multi-agent reinforcement learning algorithms suffer from several stability issues such as multi-scenario learning, unstable training in dual-reward setting, overestimation bias and value function collapse, and provide solutions to each of these problems respectively. Several contributions of this dissertation have been formalized within the framework of a defensive escort team problems, a scenario where a team of learning …

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Dordt University 2020-21 Catalog, Dordt University. Registrar's Office Jan 2020

Dordt University 2020-21 Catalog, Dordt University. Registrar's Office

Academic Catalogs

Academic catalog for 2020-21

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Use Of Rsm Technology For The Optimization Of Received Signal Strength For Lte Signals Under The Influence Of Varying Atmospheric Conditions, Shilpa Choudhary, Abhishek Sharma, Shradha Gupta, Smriti Sachan Jan 2020

Use Of Rsm Technology For The Optimization Of Received Signal Strength For Lte Signals Under The Influence Of Varying Atmospheric Conditions, Shilpa Choudhary, Abhishek Sharma, Shradha Gupta, Smriti Sachan

Electrical Engineering and Computer Science Faculty Publications

In the field of telecommunication, network planning plays an important role to maximize the system performance and it is very much related to received signal strength (RSS). While transmitting signal from the transmitter to the receiver, signal has to face so many obstacles like varying environment conditions, high-rise buildings, dense forests etc. Signal strength gets affected with varying distance between the transmitter and receiver too. So for efficient network planning, information about the effect of all these parameters on received signal strength (RSS) should be known to us. So this study aimed to investigate the variation in Received Signal Strength …

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Electrochemical Detection Of Neurotransmitters, Saikat Banerjee, Stephanie Mccracken, Md Faruk Hossain, Gymama Slaughter Jan 2020

Electrochemical Detection Of Neurotransmitters, Saikat Banerjee, Stephanie Mccracken, Md Faruk Hossain, Gymama Slaughter

Bioelectrics Publications

Neurotransmitters are important chemical messengers in the nervous system that play a crucial role in physiological and physical health. Abnormal levels of neurotransmitters have been correlated with physical, psychotic, and neurodegenerative diseases such as Alzheimer's, Parkinson's, dementia, addiction, depression, and schizophrenia. Although multiple neurotechnological approaches have been reported in the literature, the detection and monitoring of neurotransmitters in the brain remains a challenge and continues to garner significant attention. Neurotechnology that provides high-throughput, as well as fast and specific quantification of target analytes in the brain, without negatively impacting the implanted region is highly desired for the monitoring of the …

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Climate Triage: A Resources Trust To Address Inequality In A Climate-Changed World, Shi-Ling Hsu Jan 2020

Climate Triage: A Resources Trust To Address Inequality In A Climate-Changed World, Shi-Ling Hsu

Scholarly Publications

Global climate change poses an existential threat to human civilization because it disrupts the supply of natural resources that provide basic life staples-water, food, and energy. If humankind is unable to adapt to a less abundant and less predictable supply of resources, then the effective scarcity will, as it often has in human history, lead to conflict. There is a chance, if greenhouse gas emissions can be sufficiently reduced to avoid the most serious consequences of climate change, that efficiency and sharing measures can make up for climate-induced shortfalls. Natural resources are not generally managed or consumed very efficiently, so …

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Playing Disability, Daniel Romano Jan 2020

Playing Disability, Daniel Romano

Electronic Theses and Dissertations, 2020-2023

Disability in performance has a long history, starting with fictional characters such as Shakespeare's Gloucester/Richard, progressing through the freak shows of the early twentieth century, and finally with artists such as Neil Marcus, Mat Fraser and Deaf West Theatre in the past twenty years. Looking to the work of disabled artists, activists, and theorists such as Petra Kuppers and Carrie Sandahl, I will examine the history of both disability in performance and the performance of disability. I will discuss my performance of Garret, a man with muscular dystrophy, in my original play, The Sick Parents Club. Through analysis of what …

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Quantum Biology? From Dna Point Mutations To Fibril Formation In Alzheimer Disease, Eduardo Romero Camacho Jan 2020

Quantum Biology? From Dna Point Mutations To Fibril Formation In Alzheimer Disease, Eduardo Romero Camacho

Electronic Theses and Dissertations, 2020-2023

In the '60s, Löwdin explored the realm of Quantum Biology. Löwdin defined Quantum Biology as the use of quantum mechanics to study the activity and molecular properties of biologically active molecules such as DNA, RNA, and proteins. This dissertation aims to describe molecules of biological interest such as DNA base pairs and amyloid-beta peptides and treat them using a quantum mechanical approach. We used electronic structure methods to achieve the quantum biological nature of these molecules under our computational power, tools, and techniques. In chapter 2, we present the quantum mechanical description of the spontaneous mutations in DNA base pairs …

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Fluorescence Microscopy With Tailored Illumination Light, Jialei Tang Jan 2020

Fluorescence Microscopy With Tailored Illumination Light, Jialei Tang

Electronic Theses and Dissertations, 2020-2023

Fluorescence microscopy has long been a valuable tool for biological and medical imaging. Control of optical parameters such as the amplitude, phase, polarization and propagation angle of light gives fluorescence imaging great capabilities ranging from single molecule imaging to long-term observation of living organisms. While numerous fluorescence imaging techniques have been developed over the past decades, there is always an inevitable tradeoff among the spatial resolution, imaging speed, contrast, photodamage and the total cost when it comes to choose the appropriate microscope. A main goal of my dissertation research is to develop state-of-the-art microscope systems that exhibit unprecedented performance in …

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Transplant Center Criteria And Inequalities Within Transplant Wait Listing Process, Melanie Bergeron Jan 2020

Transplant Center Criteria And Inequalities Within Transplant Wait Listing Process, Melanie Bergeron

Electronic Theses and Dissertations, 2020-2023

More than 650,000 people per year in the United States are affected by End Stage Renal Disease (ESRD) (US Renal Data System, 2013). This diagnosis affects many areas of the patient's life and patients have limited options for treatment. Kidney transplantation for patients with ESRD continues to be noted as the most optimal treatment (Rubin & Weir, 2015; Maggiore, et al., 2014; Patzer, Platinga, Krisher, & Pastan, 2014). However, despite this information, utilization of transplantation remains inconsistent and variable in the population. There are many areas of disparities regarding the kidney transplant waitlist including wait times, gaining access to the …

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Exploring Preservice Teachers' Affective Response To Disruptive Student Behavior In An Immersive Simulation Classroom, Eileen Glavey Jan 2020

Exploring Preservice Teachers' Affective Response To Disruptive Student Behavior In An Immersive Simulation Classroom, Eileen Glavey

Electronic Theses and Dissertations, 2020-2023

This mixed methods study investigated changes in preservice teachers' affective response to disruptive student behavior within the TeachLivE, immersive simulation classroom. Preservice teachers completed two simulation teaching sessions, during which they were exposed to five different disruptive student behavior events in each. All teaching sessions were recorded and post-processed using iMotions Affectiva Affdex software to collect data on preservice teachers' emotion expression and valence during their teaching experiences. At the end of each teaching session, participants completed a self-report survey on their level of stress. Simulated teaching sessions were followed-up with video stimulated recall sessions where participants reflected on their …

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High Performance Micro-Scale Light Emitting Diode Display, Fangwang Gou Jan 2020

High Performance Micro-Scale Light Emitting Diode Display, Fangwang Gou

Electronic Theses and Dissertations, 2020-2023

Micro-scale light emitting diode (micro-LED) is a potentially disruptive display technology because of its outstanding features such as high dynamic range, good sunlight readability, long lifetime, low power consumption, and wide color gamut. To achieve full-color displays, three approaches are commonly used: 1) to assemble individual RGB micro-LED pixels from semiconductor wafers to the same driving backplane through pick-and-place approach, which is referred to as mass transfer process; 2) to utilize monochromatic blue micro-LED with a color conversion film to obtain a white source first, and then employ color filters to form RGB pixels, and 3) to use blue or …

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Using Project-Based Learning As A Tool For Teaching Mathematics In Urban Elementary Schools, Bernadette Jaster Jan 2020

Using Project-Based Learning As A Tool For Teaching Mathematics In Urban Elementary Schools, Bernadette Jaster

Electronic Theses and Dissertations, 2020-2023

The purpose of this study was to investigate how the lived experiences and views of fourth- and fifth-grade math teachers who implemented project-based learning (PBL) addressed the needs of their at-risk students in urban schools. The researcher examined the use of PBL in mathematics-impacted instruction, seeking to understand teacher beliefs related to the influence of exposure to PBL experiences on students' academic outcomes. When deliberately planned and embedded into teaching, the implementation of PBL helps students retain content, improve attitudes about learning, and improve their ability to collaborate with others (Cervantes et al., 2015). A literature review was conducted to …

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A Nested Pcr Strategy For Recovering Highly Discriminatory Y-Str Dna Profiles From Trace Male Dna Samples, Anna Kimball Jan 2020

A Nested Pcr Strategy For Recovering Highly Discriminatory Y-Str Dna Profiles From Trace Male Dna Samples, Anna Kimball

Electronic Theses and Dissertations, 2020-2023

DNA profiling is an effective method of identifying individuals in forensic casework. In sexual assault cases in particular, male donor DNA can be genotyped using Y chromosome short tandem repeat (Y-STR) analysis even in the presence of significant levels of female DNA. The recently released recommended national standard for sexual assault evidence collection from the victim is within 5 days after the sexual assault, with the probability of obtaining a male DNA profile diminishing significantly thereafter due to degradation and/or loss of sperm. The present study was designed to develop a method of obtaining a highly probative DNA profile with …

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Tensor Network States: Optimizations And Applications In Quantum Many-Body Physics And Machine Learning, Justin Reyes Jan 2020

Tensor Network States: Optimizations And Applications In Quantum Many-Body Physics And Machine Learning, Justin Reyes

Electronic Theses and Dissertations, 2020-2023

Tensor network states are ubiquitous in the investigation of quantum many-body (QMB) physics. Their advantage over other state representations is evident from their reduction in the computational complexity required to obtain various quantities of interest, namely observables. Additionally, they provide a natural platform for investigating entanglement properties within a system. In this dissertation, we develop various novel algorithms and optimizations to tensor networks for the investigation of QMB systems, including classical and quantum circuits. Specifically, we study optimizations for the two-dimensional Ising model in a transverse field, we create an algorithm for the $k$-SAT problem, and we study the entanglement …

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Estimation And Clustering In Network And Indirect Data, Ramchandra Rimal Jan 2020

Estimation And Clustering In Network And Indirect Data, Ramchandra Rimal

Electronic Theses and Dissertations, 2020-2023

The first part of the dissertation studies a density deconvolution problem with small Berkson errors. In this setting, the data is not available directly but rather in the form of convolution and one needs to estimate the convolution of the unknown density with Berkson errors. While it is known that the Berkson errors improve the precision of the reconstruction, it does not necessarily happen when Berkson errors are small. Furthermore, the choice of bandwidth in density estimation has been an open problem so far. In this dissertation, we provide an in-depth study of the choice of the bandwidth which leads …

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Social Justice, Inclusive Education, And Teacher Agency, Jennifer Sanguiliano Lonski Jan 2020

Social Justice, Inclusive Education, And Teacher Agency, Jennifer Sanguiliano Lonski

Electronic Theses and Dissertations, 2020-2023

Public school education in the United States has a long history of supporting societal norms within the curriculum and classroom. Through the use of social justice and inclusive education (SJIE), teachers have the unique ability to disrupt the social reproduction of inequity within their content and curriculum. In order to do this, teachers must first understand social justice and inclusive education (knowledge) and feel comfortable and confident implementing it within their classroom (agency). This study focuses on 13 public school teachers who attended a weeklong professional development program which focused on social justice, privilege, trauma-informed education, mindfulness, and inclusive education …

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Non-Linear Inverse Liquid-Solid Chromatography As A Methodology To Characterize Drug Concentration Losses To Polymeric Materials Used In Body-On-A-Chip Devices For Drug Discovery, Mark Schnepper Jan 2020

Non-Linear Inverse Liquid-Solid Chromatography As A Methodology To Characterize Drug Concentration Losses To Polymeric Materials Used In Body-On-A-Chip Devices For Drug Discovery, Mark Schnepper

Electronic Theses and Dissertations, 2020-2023

Body-on-a-chip and human-on-a-chip systems are currently being used to augment and could eventually replace animal models in drug discovery and basic biological research. However, hydrophobic molecules, especially therapeutic compounds, tend to adsorb to the polymer materials used to create these microfluidic platforms, which may distort the dose-response curves that feed into Pharmacokinetic/Pharmacodynamic (PK/PD) models which translate preclinical data into predictions of clinical outcomes. Adsorption of hydrophobic molecules to these polymer materials needs better characterization. Inverse Liquid-Solid Chromatography paired with a numerical optimization based on the Langmuir model of adsorption was used to characterize the adsorption isotherm parameters of selected drugs …

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Interdisciplinary Cybersecurity For Resilient Cyberdefense, Rachid Ait Maalem Lahcen Jan 2020

Interdisciplinary Cybersecurity For Resilient Cyberdefense, Rachid Ait Maalem Lahcen

Electronic Theses and Dissertations, 2020-2023

Cybersecurity's role is to protect confidentiality, integrity, and availability of enterprise assets. Confidentiality secures data from theft, integrity mitigates modification of data in a malicious way, and availability assures continuation of systems' access and services. However, achieving these goals is difficult due to the mushrooming of various cyber attackers that come from individuals or state actors with motives ranging from ideological, financial, state-sponsored espionage, revenge, or simple curiosity and boredom. The difficulty also lies in the complexity of the cyber layers that are not well studied. Layers that interconnect and require effective communication and collaboration. This effectiveness is still lacking …

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Preparation And Characterization Of Epitaxial Thin Films With Applications In Catalysis And Microelectronics, Asim Khaniya Jan 2020

Preparation And Characterization Of Epitaxial Thin Films With Applications In Catalysis And Microelectronics, Asim Khaniya

Electronic Theses and Dissertations, 2020-2023

Ubiquitous in the modern world, the epitaxial thin film offers a wide range of practical applications in the field of microelectronics, solar industries, optical devices, and catalysis. This thesis deals with studying the growth and characterization of molybdenum nitride (MoN) and various dielectric encapsulated Ru(0001) thin films on single-crystal substrates. The phase-specific and single-crystalline MoN film was grown epitaxially on pre-nitrogen-covered Ru(0001) via physical vapor deposition and characterized by UHV based surface science analytical techniques, including X-ray photoelectron spectroscopy, helium ion scattering spectroscopy, auger electron spectroscopy, and low energy electron diffraction (LEED). The annealing temperature of 700 K was found …

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Experimental, Analytical And Computational Analyses Of Linear And Radial Shape Memory Alloy Helical Actuators, Ryan Puchaty Jan 2020

Experimental, Analytical And Computational Analyses Of Linear And Radial Shape Memory Alloy Helical Actuators, Ryan Puchaty

Electronic Theses and Dissertations, 2020-2023

As access to Shape Memory Alloys (SMAs) has expanded beyond their use as linear wires, the need for characterizing more complex forms that account for the effects of multi-axial stress, strain, and displacement has become increasingly important in actuator design. The novel uses of SMA actuators have also moved the devices into previously unexplored loading conditions, where established theory does not adequately model the real behavior. This work seeks to alleviate some of these issues by addressing problems with the most common multi-axial stress devices: helical springs. New applications are requiring high forces in small spaces, where SMAs' high work …

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Numerical Analysis On The Geomechanical Mechanisms And Stability Of Sinkholes In Central Florida, Moataz Soliman Jan 2020

Numerical Analysis On The Geomechanical Mechanisms And Stability Of Sinkholes In Central Florida, Moataz Soliman

Electronic Theses and Dissertations, 2020-2023

Sinkholes are a common geohazard in karst areas that can threaten human life and causes significant damage to infrastructure. Approximately 18% of the United States falls into karst area where overburden soils are underlain by soluble carbonate rocks. In Florida, sinkhole-related insurance claims between 2006 and the third quarter of 2010 amounted to $1.4 billion according to the Florida Office of Insurance Regulation. Effective methods and tools for the sinkhole detection and characterization are necessary. Numerical analysis can play an important role in determining the stability of sinkholes and understanding the failure mechanism under varied subsurface geological conditions. In this …

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The Impact Of Faculty Socialization On Teaching Practices Of Postsecondary Physics Instructors, Claudine Mclaren Turner Jan 2020

The Impact Of Faculty Socialization On Teaching Practices Of Postsecondary Physics Instructors, Claudine Mclaren Turner

Electronic Theses and Dissertations, 2020-2023

This research investigates faculty socialization of college physics instructors and its effect on teaching practice. Results of two studies—a statistical analysis about professional characteristics and teaching practice and an ethnography about culture, professional roles, and teaching practice—are integrated to inform our understanding of the impact of socialization on teaching practice. These findings have the potential to improve institutional and organizational faculty development, as well as improve individual teaching practice and, by extension, student persistence and success. Exploratory factor analysis, latent class analysis, and multiple analysis of variance were used to examine cross-sectional survey data collected from 1,176 postsecondary physics instructors …

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The Implementation Of An Interdisciplinary Literacy Approach To Examine Effects On Writing Self-Efficacy In A Fourth Grade Classroom, Chelsea Wharin Jan 2020

The Implementation Of An Interdisciplinary Literacy Approach To Examine Effects On Writing Self-Efficacy In A Fourth Grade Classroom, Chelsea Wharin

Electronic Theses and Dissertations, 2020-2023

This qualitative action research examines the effects, if any at all, the implementation of an interdisciplinary literacy unit in a fourth-grade classroom had on students' perceived writing self-efficacy. This study aims to inform the teacher-researcher to make actionable changes to current teaching. Additionally, this study continues the research and discussion surrounding how educators and stakeholders approach instruction. This research required participants to complete a pre-writing self-efficacy survey, participate in an interdisciplinary literacy unit and then complete a post writing self-efficacy survey. The interdisciplinary literacy unit took place during the distance learning environment that was a result of the global pandemic, …

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Examining The Role Of Item Scrolling In Mobile Cognitive Assessment, Betsir Zemen Jan 2020

Examining The Role Of Item Scrolling In Mobile Cognitive Assessment, Betsir Zemen

Electronic Theses and Dissertations, 2020-2023

The use of mobile assessment in personnel selection is an increasing trend that offers benefits to job applicants and organizations, including increased convenience of testing and expanded applicant pools (Tippins, 2011). Fewer than 10 published studies have examined the measurement equivalence of pre-employment cognitive ability assessments administered over mobile compared to non-mobile devices. Some of this research has found evidence of measurement equivalence and no score differences across device types while other studies contradict these results (Arthur et al., 2017). The present study is the first to investigate the measurement equivalence of a mobile-delivered, adaptively administered pre-hire cognitive ability assessment. …

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Theoretical Studies Of Collisions Involving Three Bodies And Electron-Molecule Collisions Relevant To Astrophysical And Atmospheric Conditions, Chi Hong Yuen Jan 2020

Theoretical Studies Of Collisions Involving Three Bodies And Electron-Molecule Collisions Relevant To Astrophysical And Atmospheric Conditions, Chi Hong Yuen

Electronic Theses and Dissertations, 2020-2023

Accurate rate coefficients of atomic and molecular processes allow us to probe the conditions in space and understand the history of the Universe. Although experimental rate coefficients are the most desirable, availability of accurate rate coefficients of some processes depends on rigorous theoretical studies. In this dissertation, theoretical tools for collisions involving three bodies are discussed and applied to three different reactions. Rate coefficient of the reactive scattering of H2 + D- is computed using the ABC program. The present results are about ten times smaller than the experimental upper limit, suggesting that a further improvement of the sensitivity of …

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The Impact Of Athletic Coaches' Ethical Behavior On Postcompetitive Athletes, Charles Bachand Jan 2020

The Impact Of Athletic Coaches' Ethical Behavior On Postcompetitive Athletes, Charles Bachand

Electronic Theses and Dissertations, 2020-2023

Much of the literature regarding abuse in athletics has focused on the effects these actions have on the athletes both short and long term. In relation to ethics, such research has been primarily focused on how ethics effects all aspects of athletics. Therefore, the purpose of this study was to examine if factors that cause coaches to victimize athletes are related to a lack of ethical understanding. This qualitative phenomenological research design was used to highlight emerging themes revealed during the study. Thirteen purposely selected individuals, labeled as athlete, athlete/coach, or coach, participated in one-on-one semi structured interviews. The participants' …

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Diffusion Of Fission Products In Nuclear Graphite, Kevin Graydon Jan 2020

Diffusion Of Fission Products In Nuclear Graphite, Kevin Graydon

Electronic Theses and Dissertations, 2020-2023

The next generation of nuclear reactors (Generation IV) are specified to use graphite as the choice material for neutron moderation and structural components. For this reason, study of diffusion behavior of the fission product, ruthenium (Ru), in the candidate graphite grades, POCO AXF-5Q & ZXF-5Q, IG-110, NBG-18 and PCEA, is necessary. Diffusion data for Ru in these grades is absent due to the lack of prior studies and this work aims to fill this void and begin the study of this metallic fission product's diffusion behavior. By utilizing physical vapor deposition (PVD), dynamic secondary ion mass spectroscopy (SIMS), and the …

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Total Synthesis Of Natural Products From Oxidative Dearomatization, Nameer Ezzat Jan 2020

Total Synthesis Of Natural Products From Oxidative Dearomatization, Nameer Ezzat

Electronic Theses and Dissertations, 2020-2023

The goal of our research is to prepare natural products and related core structures through oxidative dearomatization. The development of a stereoselective iron (III)-mediated intramolecular cascade dearomatization of phenol allowed access to various spirocyclohexadienones and tropons in one step using potassium ferricyanide via single electron transfer (SET). Using this oxidative dearomatization reaction, the thesis focuses on three main parts. The first part is the synthetic efforts toward total synthesis of Harringtonolide. The second part focused on the synthesis of spiro[4.5]decane, a core structure in multiple natural products. The spiro compounds were prepared from ortho hydroxyphenyl nitroalkanes using SET reaction with …

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