Digital Commons Network^™

Theory Of Ultrafast Spin Crossover In Divalent Iron Systems, William Baker

Graduate Research Theses & Dissertations

A theory to account for the ultrafast, i.e. femtosecond timescale, singlet to quintet spin crossover in divalent iron molecules is developed. The model considers an iron cluster with ligands extending in all 6 cardinal directions initially at rest in a low spin singlet ground state. An optical excitation excites an electron from the d orbitals to the ligands, changing the system from the metal centered (MC) singlet state to the metal to ligand charge transfer (MLCT) singlet state. Experimentally, it is known that the system eventually relaxes into the quintet MC state, but there are no satisfactory explanations that model …

Design And Analysis Of Coupler Installation Tooling With Computer Vision For Fermilab’S Single Spoke Resonator 2 Srf Cavity, Caleb T. Denton

Graduate Research Theses & Dissertations

Fermi National Laboratory (Fermilab) and the European Council for Nuclear Research (CERN), forerunners in the exploration of the subatomic world, are both in the process of improving their particle accelerators with the Proton Improvement Plan II at Fermilab and the High-Luminosity Large Hadron Collider Accelerator Upgrade Plan (HL-LHC AUP) at CERN. Both particle accelerators have cavities that serve to either accelerate the particle beam or guide it into an optimal position and have the need for radio frequency (RF) power couplers to generate the field that controls the particle beams. When installing the coupler onto the cavity, a reliable vacuum …

Maternal Cumulative Trauma And Child Externalizing Behavior: Indirect Pathways Through Posttraumatic Stress Symptoms And Parenting Behaviors, Chynna Michelle Dubuclet

Graduate Research Theses & Dissertations

The present study aimed to add to the literature by analyzing the relationships present within the connection between maternal cumulative trauma and child externalizing behaviors. Specifically, this study examined the indirect effects that posttraumatic stress symptoms and parenting behaviors exert on the relationship between maternal cumulative trauma and externalizing behaviors. This study used structural equation modeling to assess the relationship between maternal cumulative trauma and child externalizing behaviors (i.e., conduct and behaviors, hyperactivity/impulsivity, opposition/defiance) through maternal PTSS and parenting behaviors (i.e., acceptance, lax discipline, overreactive discipline). Data was collected from 308 mothers (Mage = 20.59, 70.0% White/Caucasian) between April 2020 …

The Energetics Of Seasonality In Wild Diademed Sifaka (Propithecus Diadema): A Technical And Biological Validation Of Fecal Triiodothyronine Radioimmunassay, Casey Farmer

Graduate Research Theses & Dissertations

The energetic state of an animal has vital consequences for its fitness, but it can be difficult to detect through behavioral observations. The development of techniques to determine an animals’ energetic state non-invasively would allow conservation planners to rapidly assess the energy balance and conservation potential of individuals, groups, and populations. Thyroid hormones like triiodothyronine (T3) regulate and reflect metabolic state in mammals. T3 is a non-invasive biomarker that can be detected in feces and could potentially be used for this purpose. I perform the first validation of a commercially available T3 radioimmunoassay designed for humans on a wild strepsirrhine …

Applying Synchrotron Saxs And Xas To Study The Microstructure Of Energy Conversion And Storage Materials, Lingzhe Fang

Graduate Research Theses & Dissertations

The microstructure of energy conversion and storage materials is a key determinant of physical properties and electrochemical performance. Synchrotron X-ray techniques, with their strengths of high flux and exceptional brightness, play an irreplaceable role in understanding nano and sub-nano structures. This helps the study of reaction mechanisms and benefits material design in energy conversion and storage area. Electrifying CO2 transformation using renewable energy offers a carbon-neutral solution to CO2 recycling and fuel generation. Among various feedstocks from the CO2 reduction reaction, CO, HCOOH, and CH4 have approached the performance thresholds for industry implementation. The application of single atom catalysts (SACs) …

An Exploration Of The Sense Of Belonging For African American Women Licensed Clinicians In A Voluntary Professional Counseling Organization, Raushanah Jackson

Graduate Research Theses & Dissertations

Due to historical oppression in academe, the voices of African American women have been excluded, or unjustifiably limited, in academic research and from mainstream psychological thought. This study was one aim at understanding the experiences of belonging of women of African American ancestry who were clinically licensed professional members in a volunteer member counseling organization. Centering African American women’s voices was used through a lens of critical race theory and Black Feminist Thought to illuminate the structural, representational, and sociopolitical barriers that African American women face. An Interpretive Phenomenological Analysis approach was used to center the voices of five licensed …

Enhancing Usability In Aviation: Insights From User Experience Studies, Jennifer Ann Howard

Graduate Research Theses & Dissertations

The modern aviation industry is consistently embracing technological advancements to improve safety, efficiency, and training practices. Three user experience studies were conducted to examine the usability aspects of two digital components within aviation: the Federal Aviation Administration website and virtual reality head-mounted displays for aviation training.

The Federal Aviation Administration website serves as a central hub for aviation-related information, resources, and regulations for all domestic civil or military air operations within U.S. airspace. Usability is essential to ensure easy access to valuable data for aviation professionals, enthusiasts, and the public. Results from the experiences of ten pilots executing five tasks …

Forecasting The One Month Ahead Joint Distribution Of The Carhart Four Factor Model Using A Copula Method, Michael Nebor

Graduate Research Theses & Dissertations

The Fama and French created factors of Market minus Risk Free (Mkt-RF), Small minusBig (SMB), High minus Low (HML), and the Carhart developed factor of Momentum (MOM) are frequently used together as a four factor model to explain the variation in returns of financial equities. This paper analyzes the joint distribution of these factors by forecasting the one month ahead joint distribution using various copula based methods. The VaR quantiles are calculated throughout the forecasted distribution at the .01, .05, .25, .50, .75, .95, and .99 quantiles. The forecasted distributions are compared against each other by analyzing the exceedances of …

Understanding The Effects Of Organizational And Individual Level Motivations On Impression Formation For Persons With Disabilities In The Workplace, Lauren Francesca Luchetti

Graduate Research Theses & Dissertations

In recent years, organizations have begun paying more attention to hiring people with disabilities because of evidence supporting direct and indirect benefits to the organization. The business case for disability outlines the economic benefits for hiring those with disabilities, such as lower rates of turnover and absenteeism. Despite the motivations to hire those with disabilities, this population continues to suffer from higher rates of unemployment and underemployment. The current project attempts to shed light on the mechanisms that can improve the effectiveness of hiring motivations and disability hiring rates. In two experimental studies, the effect of the business case on …

Clinical Reasoning Development: Exploring The Role Of Instructor Feedback During Health Professions Clinical Education Experiences, Ryan T. Orrison

Graduate Research Theses & Dissertations

The growing complexity of the healthcare environment and the need to equitably address the health and well-being of a diverse patient population has increased the requirement for practical instruction and assessment of clinical reasoning in the training of health professionals. Formative assessment, in the form of feedback, is recognized as an essential instructional component in teaching clinical reasoning. This study aimed to investigate the role of feedback in developing clinical reasoning during clinical education.

This investigation consisted of three unique studies completed in phases. The scoping review methodology in phase one revealed six themes from the included articles (n = …

The Dna Double Stranded Break Damage Response Of U87 Gbm Cells Following Irradiation Treatment, Emma Louisa Planck

Graduate Research Theses & Dissertations

Glioblastoma Multiforme is one of the most aggressive forms of cancer and is becoming increasingly prevalent in the population, especially among young adults. An estimated 13,140 people in the United States will be diagnosed with GBM this year and an estimated 10,000 people in the United States will succumb to the disease. The 5-year survival for GBM patients is only 7.2% with a mean survival time of only 12-18 months. Even with subsequent chemotherapy and irradiation treatments GBM has a very high treatment resistance and has a recurrence rate of roughly 70%. Treatments such as radiation therapy induce lethal DNA …

The Future Of Convective Mode In The United States, Jeremy Malcolm Corner

Graduate Research Theses & Dissertations

This work examines potential changes in convective mode associated with hazardous convective weather (HCW) using a suite of high-resolution regional climate simulations and artificial intelligence/machine learning (AI/ML). An AI/ML model called a convolutional neural network (CNN) is first generated and validated using an existing dataset of composite reflectivity images centered on tornado reports from 1996 – 2017 called SVRIMG (SeVeRe IMaGes). Each image in SVRIMG is annotated with four possible convective modes: 1) cellular; 2) mixed mode; 3) linear; and 4) other. The best-performing model, which achieves an accuracy exceeding 90% on testing images, is then used to diagnose storm …

Evaluating Computational Reproducibility Of Jupyter Notebooks Using Machine Learning And Natural Language Processing, A S M Shahadat Hossain

Graduate Research Theses & Dissertations

In recent years, computational reproducibility, which refers to achieving consistent results upon rerunning an experiment, has become one of the major concerns of various research communities. Jupyter Notebook, as a web-based computational notebook application, offers useful features for running and publishing computational experiments through interactive environments. However, rerunning notebooks does not always reproduce the experimental results. This thesis aims to develop novel methods to evaluate reproducibility by comparing different types of outputs between original and rerun notebooks. It also explores the idea of using machine learning models to predict reproducibility of notebooks automatically without the need of rerunning them. Through …

Essays On Institutions And Business Performance In A Less-Developed Economy, Obinna Franklin Ezeibekwe

Graduate Research Theses & Dissertations

The dissertation comprises three essays that collectively contribute novel insights into the impact of institutional and regulatory factors on firm performance in Nigeria.

The first essay presents the first empirical assessment of the causal heterogeneous effects of competition from informal firms on the revenue of Nigerian formal firms using quantile regression, causal mediation analysis, and non-parametric preprocessing matching. The theoretical framework mathematically depicts how informality determines formal firm revenue by influencing prices.

In the second essay, I provide the first empirical assessment of the causal impact of bureaucratic corruption on firms' financial constraints in Nigeria by calculating treatment effects using …

Reinterpreting Fort Ancient Plant Relationships Through Native Science And Traditional Ecological Knowledge, Bailey Rae Raab

Graduate Research Theses & Dissertations

Paleoethnobotanical analyses over the past several decades have shed light on subsistence practices, agricultural strategies, and environmental interactions of members of the Fort Ancient culture, an Indigenous society that thrived in the Ohio Valley from 1000 to 1650 CE. Largely absent from these conversations, however, are discussions of non-food uses of plants or considerations of Traditional Ecological Knowledge (TEK). By combining multiple different sources of knowledge, a more holistic view of people-plant relationships within the Fort Ancient culture may be established, one that allows us to better understand these relationships in the past and present. In this thesis, I synthesize …

Experiences Of Discrimination, Covid-19 Stress, And Racial Trauma In College Students, Jennifer Valentine

Graduate Research Theses & Dissertations

Extant literature has illustrated the devastating effects of repeated exposure to discriminatory events on Black, Indigenous, and People of Color (BIPOC), leading to the development of a psychological injury, known as racial trauma. Research has suggested that racial trauma can sensitize individuals to future stressors, potentially placing marginalized populations at risk of developing adverse mental health outcomes due to the pervasive effects of systemic racism. While the literature on racial trauma is expanding, there remains a paucity of research examining racial trauma in the context of inequity in communities of color, such as during the COVID-19 pandemic. In addition, despite …

Development Of A Novel Prosocial Teasing Measure For Adolescents, Kristina Wiemer

Graduate Research Theses & Dissertations

Prosocial teasing is a fun, playful way for students to interact with each other that involves humorous off-record markers and playful provocation. While research has been done to observe prosocial teasing in school-aged youth, there are no validated measures of prosocial teasing that are designed to measure prosocial teasing frequency in adolescents. The current study extended the research on prosocial teasing through the validation of a novel, adolescent-specific measure of prosocial teasing behavior frequency. The current study also explored gender and grade-level differences in self-reported prosocial teasing frequency. Results indicated a one factor structure to the novel prosocial teasing measure …

Three Essays On The Impact Of Debt On Young American Adults’ Lives After Graduation, Sylvie Sanou

Graduate Research Theses & Dissertations

This dissertation investigates the impact of financial constraints due to debt on three aspects of young American adults' lives after graduation. The first essay examines the impact of student loan debt on the mental health of US young adults using restricted-access and publicly available data from the 1997 National Longitudinal Survey of Youth (NLSY97). Prior studies found that debt negatively affects mental health. However, few papers focused on educational debt. Unlike other debt, student loan debt is special because it funds human capital investment, and borrowers expect to receive a significant return on the investment. Using a two-stage estimation model, …

Latine Caregiver Perspectives Of Their Child’S Speech And Language Services, Marisol Perez

Graduate Research Theses & Dissertations

Early Intervention (EI) speech-language pathologists (SLPs) are mandated to provide culturally responsive services to culturally and linguistically diverse (CLD) clients. However, little is known about Latine caregivers’ perspectives on receiving these services. The purpose of this study was to examine Latine caregivers’ perspectives on their child’s speech and language services by answering the following research questions: 1) How do intrinsic factors relate to Latine caregiver satisfaction with their family’s speech and language services? 2) Does perception of clinician cultural sensitivity relate to Latine caregiver satisfaction with speech and language services? 3) What do Latine caregivers perceive as determinants (facilitators and …

Iodp U1537: Scotia Sea Climatic And Frontal Variation Reflected In Diatom Productivity And Assemblages Since The Lgm, Garrett Lewis Strittmatter

Graduate Research Theses & Dissertations

Located off the coast of the West Antarctic Ice Sheet, the Scotia Sea is a site of great significance in palaeoclimatological studies due to the nature of its sedimentary record. This site of interest is at the tip of the Antarctic Peninsula on the Eastern side, in the direct flow of the Antarctic Circumpolar Current thereby concentrating icebergs from around the continent. Additionally, these sediments are rich in diatoms. Finally, this site, within the analyzed section, has an average sedimentation rate of ~48 cm/Kyr.

By collecting sediment cores rich in diatoms, among material used to generate other paleoclimate proxies, we …

An Environmental Isolate Of Pseudomonas, 20ei1, Reduces Aspergillus Flavus Growth In An Iron-Dependent Manner Affecting The Expression Of Numerous Genes, Elizabeth Marion Wyman

Graduate Research Theses & Dissertations

Aspergillus flavus is an opportunistic pathogenic fungus that infects oilseed crops worldwide. When colonizing the plants, it produces mycotoxins, including carcinogenic compounds such as aflatoxins. Mycotoxin contamination results in an important economic and health impact. The design of new strategies to control A. flavus colonization and mycotoxin contamination is paramount. In this study, we identified a promising new isolate of Pseudomonas spp., 20EI1, and observed that it is able to reduce the growth of A. flavus AF70. Furthermore, we determined that this growth inhibition is iron-dependent. To further elucidate the nature of this bacterial-fungus interaction, we performed metabolomics and transcriptomics …

Dna I-Motifs: Biophysical Characterization And Structure-Property Correlation As Foundation For Functional Material Design, Alexander Minasyan

Graduate Research Theses & Dissertations

Over the past decades, nucleic acids have emerged as crucial frameworks with significance in biological systems and functional material engineering. Cytosine-rich deoxyribonucleotide sequences can form quadruplex structures a.k.a. i-motifs. Recently, i-motifs have attracted scientific interest in biological and material design areas.

In this work, we systematically investigate an effect of structured and unstructured modifications such as hairpins, stems, loops and overhangs on the kinetic and thermodynamic properties of DNA i-motifs. We demonstrate that the modifications can influence i-motif’s stability and folding/unfolding rates: thus, double stranded stems and hairpins are the best at stabilizing i-motifs and increasing kinetic rates of folding. …

Journalists’ Perception Of Artificial Intelligence: The Case Of Nigerian Newsrooms, Amaka Peace Onebunne

Graduate Research Theses & Dissertations

Technological advancements have always influenced how news is sourced, produced, and disseminated. The emergence of AI technology fundamentally repositions human journalists, requiring them to work with non-human agents. Typically, the Global North leads in adopting such technologies, resulting in unequal technological diffusion and research between the Global North and South. This research thus takes a less-traveled path within a portion of the global south to understand journalists’ views of Artificial Intelligence in Nigerian newsrooms and how geographical and cultural factors influence AI usage. Grounded in the human-machine communication framework, semi-structured interviews with 18 Nigerian journalists revealed a double-edged view of …

Gmm And Asset Pricing Model, Yuzhou Liu

Graduate Research Theses & Dissertations

The traditional two-pass regression to estimate risk premium has shortcomings. To get the correct asymptotic standard errors, we need to estimate both time-series regressions and cross-sectional regressions simultaneously. The Generalized Method of Moments (GMM) effectively addresses this issue by its nature fit of asset pricing model. In this paper, I re-examine the risk premium of Carhart’s four-factor model by integrating time-series and cross-sectional regressions within the GMM framework, which enhances the accuracy and reliability of the risk premium estimates.

Examining Relations Among Educator Demands, Burnout, And Engagement: Work Recovery As A Moderator During Covid-19, Kellie Menter

Graduate Research Theses & Dissertations

Education is described as a fulfilling career field; however, educator shortages associated with burnout and job dissatisfaction constitute a major issue in public education currently. During the COVID-19 pandemic, new challenges resulted in increased job stress for many educators. Using survey responses of a sample of 159 educators from a midwestern public school district, the current study explored whether a personal resource, work recovery experiences, was associated with educator burnout and work engagement during the context of remote instruction associated with the COVID-19 pandemic. Results indicated psychological detachment significantly moderated the relation between demands and burnout. However, control over leisure …

Essays On Computational And Financial Economics, Mohammadreza Mahmoudi

Graduate Research Theses & Dissertations

This dissertation comprises three essays centered on computational and financial economics, addressing the economic implications of the COVID-19 pandemic, the interplay between monetary policy and the cryptocurrency market, and the strategies for cryptocurrency portfolio optimization.

In the first essay, the spotlight is cast on the U.S. government's response to the COVID-19 pandemic and its subsequent economic ramifications. The study meticulously assesses the implemented uniform pandemic control policies and contrasts them with potential targeted measures. These targeted strategies take into account the differential effects of the virus on various age demographics. By employing the adjusted SEQIHR model as a tool for …

Tracing Past Climate Signals Through Multi-Proxy Analysis: Insights From Sedimentary Plant Wax Hydrogen Isotope Data And Long-Term Hydroclimate Records In Estonia, Mariliis Eensalu

Graduate Research Theses & Dissertations

In light of the rising global temperatures, there is an increasing need to understand the potential shifts in hydroclimate. Past climate reconstructions offer a glimpse into the possible temperature-moisture dynamics by providing quantitative constraints for hydroclimate variability under different temperature conditions, which can ultimately aid in decreasing the uncertainty in future climate projections. The research presented in this dissertation focuses on utilizing various proxies to reconstruct past hydroclimate conditions, particularly in the Baltic region, with a specific emphasis on Estonia. The second and third chapter aim to improve the understanding of sedimentary plant wax hydrogen isotope (δ2H) data by first …

Will The Real J.G. Ballard Please Stand Up?, Scott Richard Stalcup

Graduate Research Theses & Dissertations

This dissertation examines the longer works of British colonial author James Graham Ballard. Specifically, it attempts to answer the long-deflected question posed over the decades to Ballard regarding the treatment of female characters in his fiction. Though espousing liberal feminist ideals at times, Ballard’s repeated use of the lamia/damsel archetype, often in the same female character, strongly suggests he believed otherwise. Using predominantly radical-cultural feminist criticism as a critical lens, specifically the works of Ballard’s long-time nemesis Andrea Dworkin, this study focuses predominantly on the thematic tetralogies of Ballard’s fiction: the ecological disasters of the 1960s, the “techno-barbarism” of the …

A One-Wheeled Robot For Exploring Rolling Disk Locomotion, David H. J. Schmidt

Graduate Research Theses & Dissertations

The work proposed in this thesis is motivated by observations of one-wheel vehicles called monocycles. Whereas the unicycle has the rider sitting on a seat above the wheel, the monocycle’s rider sits inside a large circular hoop that serves as the wheel. Due to the position of the rider inside the wheel, it lowers the overall center of mass of the vehicle below the center of the wheel. For this reason, the uncontrolled longitudinal (forward/backward, or drive axis) dynamics are stable. For modest speeds above a certain threshold, the lateral (side-to-side, or lean axis) dynamics of the monocycle are also …

There Is No Substitute For A Lifetime: A Study Of Metaphor And Linguistic Autonomy In The Lives And Works Of Selected American Poets, Richard Tony Thompson

Graduate Research Theses & Dissertations

Metaphor is not only figurative language, but also a way of understanding reality and creating truth. This study describes how selected American poets, including Tom Andrews, Patti Smith, and Natasha Trethewey, engage the concept of creation through metaphor in their poetic and autobiographical writing. Theories of signification, symbolism, and metaphor as defined by philosophers of language, including George Lakoff, Charles Sanders Peirce, and Roman Jakobson, are combined with complementary theories from philosophers of poetry, including Wallace Stevens, Jorie Graham, and Federico García Lorca, and used as a lens through which to view the agency of the language user as a …