Digital Commons Network^™

Long Term Dynamics Of A Stage Structured Population Model With Nonlocal Dispersal, Md Yasin

Graduate Research Theses & Dissertations

This thesis is based on the 2023 paper “Dynamics of Classical Solutions of a Two-Stage Structured Population Model with Nonlocal Dispersal.” We study the long-term behavior of a population with two life stages, juvenile and adult, moving across space using nonlocal dispersal mechanism. The main goal is to understand the conditions under which the species survives or goes extinct on the long run. This is determined by a key value called the principal spectrum point, λp.

First, using results from the literature on existence of solutions for general initial value problems on Banach spaces, we establish that for any given …

Rise Or Retreat: The Role Of Appraisal And Goal Orientations In Leader Engagement, Haleigh Broucher

Graduate Research Theses & Dissertations

This dissertation examines how leaders psychologically interpret developmental challenges as threats or challenges, and how these interpretations shape engagement. Furthermore, I propose that these processes are shaped by mastery-approach and mastery avoidance orientations. Study 1 manipulated the presence of developmental challenges to test causal pathways. Results indicated that developmental challenges increased threat appraisal but not challenge appraisal, and threat was negatively associated with absorption. Study 2 found the opposite pattern: challenge appraisal, not threat appraisal, explained engagement. Relative importance analysis showed that challenge appraisal accounted for nearly all explained variance in engagement (97.6%). There was no significant moderation of mastery …

Thai Pre-Service And Early-Career Teachers' Professional Identity Formation, Duangkamon Winitkun

Graduate Research Theses & Dissertations

Beginning teachers, including pre-service (PSTs) and early-career teachers (ECTs), face various types of challenges such as classroom management, instructional planning, building relationships with school stakeholders, adjusting to school culture, and limited resources (Kozikoglu, 2017). Many studies focus on these challenges as technical issues, neglecting the role of teacher identity in how educators experience and address these difficulties (e.g., Burden, 2020; Doyle, 1990; Hoy & Weinstein, 2013). Moreover, most teacher identity studies are predominantly conducted in Western contexts where sociocultural values and systemic constraints shape teachers’ professional roles differently from those in Eastern contexts. This three-manuscript dissertation investigates the identity formation …

Functional And Structural Impacts Of Bison Grazing Intensity On Plant Communities, Samantha Lynn Berk

Graduate Research Theses & Dissertations

The reintroduction of grazing disturbance has become an increasingly popular tool in grassland restoration to build and maintain diverse and functioning ecosystems, but our understanding of how grazers like bison (Bison bison) shape plant communities is limited by binary grazing treatments and unanswered calls for in-depth and mechanistic examinations of community function and structure. Little research has focused on how natural variations in bison grazing intensity impact the function and structure of restored tallgrass prairie; whereby functional diversity is purely defined by changes in trait expression according to plant responses to grazing, and examining both vegetation structure and ecosystem function …

Size Dependent Thermodynamic Properties Of Dppc, Zhenghao Pan

Graduate Research Theses & Dissertations

This study explores the viability of measuring the melting transition behavior in a simple unilamellar vesicle (LUV/SUV) liposome (DPPC surfactant) system using size data from Dy- namic Light Scattering (DLS). The melting transition of phospholipid membranes has been a focal point of studies in biological systems. Conventionally, the transition temperature of a membrane system is measured using either spectroscopy or Differential Scanning Calorimetry (DSC). By assuming that the bilayer volume is conserved, it is shown that DLS provides a transition signal comparable to that of DSC and aligns with known data. The data are fit- ted using Van’t Hoff’s equation. …

Learning Through Following: The Role Of Social Foraging In Juvenile Saddleback Tamarin (Leontocebus Weddelli Weddelli) Development In The Department Of Pando, Bolivia, Meghan E.F. Hanson

Graduate Research Theses & Dissertations

Across the primate order, the juvenile stage is an important period of development that transitions individuals from infancy to adulthood. During the juvenile stage, individuals are weaned but lack experience feeding and foraging on solid foods. As a result, juveniles must learn foraging and feeding skills during this vital period of growth and development. The purpose of this study is to assess how juvenile saddleback tamarins (Leontocebus weddelli) gain foraging and food manipulation skills. During this study, I observed feeding behaviors in a group containing two juveniles and four adults, located at the Estación Biológica Tahuamanu in the Department of …

Cut It Out And Cut Us In: The Evolution Of Chicago’S Militant African-American Youth Activism During The 1950s And 1960s, Sultaan Edward Byrd

Graduate Research Theses & Dissertations

This dissertation tracks the development of a militant core in Chicago’s African American youth community following the lynching of one of the city’s native sons, Emmett Till, in 1955, through the rise of the fight against housing and school segregation and culminating in demands for racial equity in the building trades in 1969. This dissertation will trace how events in Mississippi helped plant the seeds of resistance and shape the trajectory of black activism in Chicago, revealing a powerful link between Southern racial violence and Northern political awakening. The coalitions that emerged in response to Till’s murder laid the foundation …

Yoga As A Self-Care Practice For Mental Health Counselors Who Treat Trauma, Kari Michelle Fitzgerald

Graduate Research Theses & Dissertations

Given the high rates of burnout and compassion fatigue among trauma-exposed counselors, understanding effective self-care practices is critical for sustaining clinical effectiveness and well-being. Utilizing Interpretative Phenomenological Analysis (IPA), exploration of the lived experiences of licensed mental health counselors who treat trauma and use yoga as a self-care practice was conducted. Eight participants who were regular yoga practitioners each participated in one semi-structured interview and submitted one pre- and one post-interview reflective journal entry. Thematic analysis was used to identify six major themes; 1) emotional impact and sacred responsibility of clinical work, 2) yoga as a regulating and restorative practice, …

The Emotional Burden Of Teaching: Understanding And Addressing Secondary Traumatic Stress In Middle School Teachers, Lisa Marie Lazansky-Roach

Graduate Research Theses & Dissertations

Secondary traumatic stress (STS) has been extensively documented in helping professions such as healthcare and social work, but its impact on teachers, particularly middle school educators in high-need, low-income districts, remains underexplored. This three-manuscript dissertation examines the prevalence, predictors, and support of STS in this population.

The first study uses a quantitative survey to measure STS severity among 6th–8th grade teachers to assess how it relates to demographic characteristics, including age, gender, race/ethnicity, and teaching experience. Results indicate that a substantial proportion of teachers experience moderate to severe STS, with race emerging as a significant predictor. The second study analyzes …

Characterization Of A Large-Scale Electrohydrodynamic Vortex Confinement Flow For Particle Agglomeration, Sanjay Dangi

Graduate Research Theses & Dissertations

With industrialization and the increasing use of microplastics and nanoparticle-based products, the concentration of fine particulate matter (PM2.5) in the biosphere has increased due to the disposal of manufacturing waste and expired parts. If inhaled, PM2.5 can have detrimental health effects, as these particles can travel deep into the lungs and even penetrate blood vessels. Conventional fabric filters used for indoor air quality control have drawbacks, including the need for periodic filter replacement and a high-pressure drop across the filter over time, which leads to increased power consumption. In power plants, electrostatic precipitators (ESPs) are primarily used to collect fly …

Methods For Finding High Quality And Optimal Solutions Of Binary Quadratic Optimization Problems, James Haas

Graduate Research Theses & Dissertations

BiqAlps is an extension of the BiqCrunch project that leverages its bounding procedures within a computer cluster environment. The primary goal of this work was to investigate whether distributing the branch-and-bound tree search across multiple CPUs could improve solve times. While some problem instances demonstrated speedups of up to fivefold, others showed no measurable improvement, revealing that parallelization benefits are problem-dependent.

Beyond parallelization, BiqAlps introduces enhanced heuristics for generating high-quality initial solutions and refining existing ones. Additionally, the framework explores the impact of propagating triangle inequality cuts to child nodes during search, with the aim of accelerating bounding processes and …

The Long Border: The Politics U.S. Immigration Policy Makes, John Peter Hansberry

Graduate Research Theses & Dissertations

This thesis examines how the structural context of presidential leadership influences immigration policy outcomes, with a focus on the interplay between a president’s political regime position and the level of legislative gridlock. Drawing on the American Political Development tradition, this study integrates regime theory, congressional gridlock research, and scholarship regarding executive power to formulate a framework of presidential strategic choice. Seven U.S. presidencies are analyzed as case studies: Lyndon B. Johnson, Jimmy Carter, Ronald Reagan, George H. W. Bush, Bill Clinton, George W. Bush, and Barack Obama, representing diverse regime affiliations and degrees of partisan polarization. This thesis shows that …

Piv Visualization Of A Sinusoidal Ehd Confinement Flow Induced By Variation In Ion Density For Electrostatic Particle Agglomeration, Md Eyasin Hossain

Graduate Research Theses & Dissertations

Long-term exposure to PM2.5, which is responsible for four million cardiovascular-related deaths worldwide, is a major concern as people spend 90% of their time indoors. Fabric filters have been commonly utilized for particle pollution control in indoor settings. However, the maintenance cost of fabric filters is relatively high, as particle accumulation on filters can lead to higher pressure drops (45 ∼ 300 Pa) and energy consumption, as well as the growth of biological organisms and the generation of airborne pathogens. An electrostatic precipitator (ESP) is filterless and widely used in the electric power industry for collecting coal fly ash. ESPs …

Cubic Blaschke Products, Alexandra Hill

Graduate Research Theses & Dissertations

It is well known that Blaschke products can be classified as elliptic, hyperbolic, or parabolic. Based on the classification of the Blaschke product, we know that the Julia set is either the entire unit circle or a Cantor subset of the unit circle. For unicritical Blaschke products of degree d, it has been shown that the parabolic functions are parameterized by an epicycloid with d-1 cusps, with the interior of the epicycloid giving rise to the elliptic parameters, and the relative complement of the epicycloid within the unit disk providing the hyperbolic parameters. In this dissertation, we study in more …

"On The Mat They Will Get Treated The Same": Male High School Wrestlers' Attitudes Towards Female Opponents, Emily Ann Kaht

Graduate Research Theses & Dissertations

Wrestling has historically been considered a male sport. Until recently, so few girls wrestled that those who did had no choice but to take on male opponents. Media reports and the literature indicate that those girls faced a wide range of attitudes from their opponents. While some women reported feeling supported by their male teammates, others reported hostility. Some stakeholders have, in the past, argued that wrestling is inherently unsuitable for girls, and some girls had trouble securing matches due to widespread refusal of boys to wrestle against them. Reasons given for boys forfeiting against girls have included a fear …

Three Essays On Asset Pricing And Risk Factors, Yuzhou Liu

Graduate Research Theses & Dissertations

This dissertation explores whether alternative economic and financial factors serve as risk factors in asset pricing. It consists of three essays that examine policy uncertainty, macroeconomic expectations, and accounting-based factors in asset pricing models. The first essay studies the shocks in U.S. Economic Policy Uncertainty (EPU) index and its categorical indices. Shocks in monetary policy uncertainty and sovereign debt/currency crisis policy uncertainty significantly price assets and earn significant premiums. The second essay distinguishes expected (ex-ante) and realized (ex-post) macroeconomic factors using a state space model via Kalman filter. Ex-ante economic activity are significantly priced along with ex-post size, ex-post and …

Experimental Demonstration Of A Metallic Sub-Terahertz Structure For High-Gradient, High-Efficiency Acceleration, Brendan Leung

Graduate Research Theses & Dissertations

Future accelerator facilities are increasingly constrained by the cost and footprint of conventional radiofrequency technology. Advancing both accelerating gradient and beam-to-wake energy transfer efficiency in the sub-terahertz (sub-THz) regime offers a credible path toward compact machines. Short wavelengths strengthen beam–structure coupling and enable small-aperture, high-impedance geometries; paired with tailored drive-beam current profiles, they can simultaneously raise gradient and transformer ratio.

This dissertation reports the design, fabrication, and beam testing of a sub-THz structure-wakefield accelerating (SWFA) device evaluated at the Argonne Wakefield Accelerator (AWA). The emittance-exchange (EEX) beamline was used to generate prescribed longitudinal current profiles in two modes: (i) a …

Constraining The Timing And Degree Of Metamorphism In The Echo Canyon Region: Evidence For A Cryptic Contact Aureole, Keanu Montañez

Graduate Research Theses & Dissertations

Local occurrences of andalusite and kyanite in Echo Canyon, within the Funeral Mountains metamorphic corecomplex, overprint chlorite-grade phyllites and reveal the presence of a hidden pluton and its contact aureole. Phase equilibria models indicate minimum conditions of 0.45 GPa and 535 °C in the highest-grade zone of the aureole, with significantly higher temperatures than previously estimated for the area. This study applied phase equilibria pressure-temperature modeling, petrography, Raman spectroscopy, and ⁴⁰Ar/³⁹Ar geochronology on muscovite to characterize this anomalous metamorphism and to place it within a revised tectonic framework. Two potentially coeval prograde metamorphic events have been recognized based on petrographic …

Same Constructs, Different Functioning: A Rasch-Based Investigation Of Sel Item Performance Among Multilingual Students In Nigeria, Nkem Ndem

Graduate Research Theses & Dissertations

As SEL assessments gain traction globally, questions concerning their cross-cultural validity have become increasingly salient, particularly in linguistically diverse contexts where language and cultural schemas may differentially shape students' interpretation of socioemotional constructs. This study employed Rasch modeling and differential item functioning (DIF) analyses to examine the psychometric performance of the Social Skills Improvement System - Social Emotional Learning Brief Scales (SSIS-SELb) among 192 middle school students attending an international school in Lagos, Nigeria. All participants were proficient in English; however, they differed in native language (English: 43.1%, Yoruba: 23.1%, Igbo: 16.5%) and country of birth (Nigeria: 22.0%, United States: …

Climate Migration And Urban Survival: Evidence From Chittagong’S Slums, Mohammad Nur Nobi

Graduate Research Theses & Dissertations

This study examines the impact of climate change on rural-to-urban migration in Chittagong, Bangladesh. Based on a primary survey of 400 respondents across 35 slums in the country's second-largest city, the analysis employs two estimation methods: a multinomial logit model to assess the influence of climate-related factors on migration decisions, and a logit model to evaluate the impact of migration on the living conditions of migrants. The results show that individuals involved in ‘agriculture and daily labor’ are most likely to migrate. Compared to the base category (‘Other Reasons’) for migration, the odds ratios for ‘floods’, ‘droughts’, and ‘better job …

Examining The Role Of Affective Arousal In Future-Choice Processing, Justine Sara Rivard

Graduate Research Theses & Dissertations

Humans employ different processes of decision-making, depending on a variety of factors including the temporal situation of the potential outcome. This study proposes a hybrid, dual-systems theoretical model of future-choice making, with an arousal-based switch as the main predictor of the decision-making process employed. Using a sample of 120 undergraduate participants, this relationship was explored using an episodic future-thought cue, paired with a temporal-discounting task in the same timeframe. Response times were measured to identify which of the proposed decision-making processes were employed, as well as temporal discounting rates for each participant. An ANOVA showed that there was no significant …

Does Fairness Shape Environmental Attitudes? Evidence From Nigeria’S Extractions, Isaiah Chukwudi Samuel

Graduate Research Theses & Dissertations

This thesis argues that citizens’ perceptions of fairness in the distribution of natural resource revenues influence their support for environmental regulation in Nigeria. The analysis shows that individuals who perceive revenue distribution as fair are more likely to back environmental policies. Utilizing data from Afrobarometer Round 9, this study employs logistic regression to assess this relationship while controlling for demographic and attitudinal factors, including age, education, urban residency, climate awareness, trust in government, and party affiliation. The results demonstrate a strong and statistically significant relationship between perceived fairness and support for environmental regulation, even after isolating these variables. Overall, the …

Sensitivity Studies Of Vector-Like Quark (Vlq) Pair Production In The Full-Hadronic Channel At The High-Luminosity Large Hadron Collider (Hl-Lhc) And A 10 Tev Muon Collider, Olabisi Olayinka

Graduate Research Theses & Dissertations

Vector-like quarks (VLQs) appear in various extensions of the Standard Model that consider a new strongly interacting sector to resolve the fine-tuning problem. These new particles can provide radiative corrections to the Higgs mass while also having electroweak-singlet masses. This latter property would allow them to escape existing constraints from Higgs boson measurements and electroweak precision data, which disfavor the existence of a fourth generation of quarks.

VLQ can be produced at colliders, with a variety of production modes and decay mechanisms open for study. In this work, we investigate the pair production of VLQ Tops (T), which are assumed …

Stop Shying Away From Race: Black Americans’ Cultural Models For Shyness, Carrie Zack

Graduate Research Theses & Dissertations

This study explored how African American adults understand and experience shyness, with particular attention to the influence of race and racism. While most psychological research on shyness has largely centered white experiences and treated race as a peripheral variable, this study applied Critical Race Theory and Cultural Model Theory to investigate whether Black Americans share a cultural model for shyness. Using semi-structured interviews with sixteen African American adults, the study sought to uncover shared mental frameworks that guide interpretations of shy behavior, especially in contexts involving unfamiliarity or potential negative evaluation.

Contrary to expectations, the findings did not support the …

Md Simulation Of Femtosecond Laser-Controlled Melting Of Multiple Core-Shell Nanoparticle Systems, Shivansh Patel

Graduate Research Theses & Dissertations

This thesis presents a molecular dynamics (MD) simulation study of femtosecond laser-induced melting and heat transfer in multiple Cu–Al core–shell nanoparticle systems. The research builds upon previous single-particle studies and extends the investigation to multiple interacting nanoparticles to better understand nanoscale thermal transport and melting behavior under ultrafast laser irradiation. Understanding this process is essential for improving laser-based additive manufacturing and sintering of metal matrix nanocomposites (MMNCs), where precise control of heat flow and particle bonding determines the final material quality. The simulations were performed using the Large-scale Atomic/Molecular Massively Parallel Simulator (LAMMPS) integrated with the Modified Two-Temperature Model (MTTM). …

Simulated Efficiency Of A Modified Bmw I3 Traction Motor Operating As An Isolated Dc-Dc Converter, Shayne Taylor

Graduate Research Theses & Dissertations

Battery electric vehicles are currently fighting to have any advantage over internal combustion engine powered vehicles to reduce global transportation greenhouse gas emissions. Electric motors are typically deemed as the largest source of loss in many vehicles but have recently become more efficient on average than the AC-DC converter used to charge the vehicle. This paper investigates the potential for a dual three phase electric traction motor based on a BMW i3 electric vehicle traction motor to take the place of an isolated DC-DC converter, an important part of the AC-DC converter. This electric machine in simulations produced a similar …

Vascular Dementia, Kayley Anderson

The Art of Medicine

No abstract provided.

The Art Of Auscultation, Stephanie Dong

The Art of Medicine

No abstract provided.

"Neuroradiology And The Humanity Of It," "Skull With Ginko" And "Sphenoid", Andria M. Powers

The Art of Medicine

No abstract provided.

Ode To An Earthworm, Sarah Chandler

The Art of Medicine

No abstract provided.