Dissertation defense schedule

THE RELATIONSHIP BETWEEN DUAL LANGUAGE TEACHERS’ EXPERIENCES AND MOTIVATION WHEN IMPLEMENTING THE WORKSHOP MODEL IN READING

This quantitative correlational study, grounded in Deci and Ryan’s Self-Determination Theory, aimed to understand the motivation of dual-language teachers who use the workshop model to teach reading and to determine whether their motivation is related to their background
experiences. The study’s participants were dual-language teachers from three school districts and a member-only bilingual social media website. Participants (N = 52) completed background questions and the Intrinsic Motivation Inventory (IMI). The researcher calculated Spearman’s rankorder correlation coefficients to determine whether relationships exist between participants’ background experiences and motivation.

Overall, participants reported greater-than-moderate motivation to implement the workshop model (M = 4.88, SD = 1.26), and they scored highest on the Effort/Importance subscale (M = 6.00, SD = 0.87), suggesting that teachers who implemented the workshop model valued its instructional importance and effectiveness. The Perceived Competence mean was also high (M = 5.56, SD = 1.16), suggesting that participants felt capable of implementing the workshop model overall. Finally, the Perceived Choice subscale had the lowest mean (M = 4.36, SD = 1.57), which may indicate that while dual-language teachers who implement workshop reading instruction felt they had some choice in using the workshop model, that choice was limited. When considering possible relationships between background experiences and motivation, two subscales were statistically significant. Dual-language teachers who reported having the most experience teaching reading in a dual-language classroom and those who felt they had more access to high-quality materials and resources perceived themselves as more competent. Enjoyment of implementing the workshop model did not correlate with their professional development or the support and resources they received. The results support the idea that dual-language teachers value using the workshop model to teach reading, feel competent implementing it, and that additional support and resources do not increase their enjoyment. This study implies that educational policymakers should consider dual-language teachers’ psychological needs to best support educators.

A CALL FOR SYSTEMATIC VALIDATING PRACTICES FOR
FIRST-GENERATION COLLEGE STUDENTS (FGCS)

This qualitative multi-site case study examined what ecological factors (people, processes, context, and time) affect the ability of faculty, staff, and other stakeholders to collaborate towards implementing and sustaining systematic validating practices for first-generation college students (FGCS or FGS) and how validating practices become systematized across a university. Framed by Bronfenbrenner’s ecological systems theory (1979, 1993) and grounded in Rendón Linares and Muñoz’s (2011) extended theory of validation, the study focused on the university exosystem, or the sphere in which students are indirectly influenced by institutional structures, policies, and relationships.

The study was conducted between November 2024 and August 2025, a period characterized by organizational instability and transition in the aftermath of the COVID-19 pandemic, at two Jesuit, Catholic universities with institutionally supported programs for FGCS. Data were collected through document analysis, focus groups, and semi-structured interviews with faculty, staff, and administrators involved in FGS support efforts. Data were analyzed using cross-case thematic analysis to identify patterns related to the development, implementation, and sustainability of validating practices.

Findings indicated that validating practices became systematized through four interrelated processes. First, a mission-anchored culture of care supported 1) the development of wraparound structures, 2) everyday care as policy that affirmed FGS, and 3) intentional hiring
for mission. Second, data-to-action communication cycles helped institutional stakeholders to 1) elevate counternarratives, 2) codify the FG identity, and 3) leverage FG data strategically to advocate for student needs. Third, constructive allyships and coalition-building across
departments bolstered collaboration and broadened responsibility for FGCS success. Fourth, systematic validating practices were sustained through flexible and resilient leadership, reflective practice, and responsiveness to institutional change over time, including a period of high staff turnover and burnout.

The findings suggest that validating practices for FGCS are most sustainable when they are woven into institutional structures, communication routines, and collaborative institutional culture rather than isolated within individual programs. The findings of this study contribute to the literature by further extending ecological systems theory to higher education contexts and demonstrating that collaboration towards systematic and sustainable practices can be achieved through coordinated institutional action.

MORAL REMAINDER AND VIRTUE: THE FORMATIVE POTENTIAL OF MORAL DILEMMAS IN A COMPLEX WORLD

Recent scholarship in ethics has begun questioning the rationalist assumption that moral dilemmas do not (and cannot) exist. The questions proceed by attention to the experience of “moral remainder,” that is, moral emotions (such as guilt, regret, and remorse) that linger following situations where an agent experienced all their possible actions (or in-action) as falling short of moral demands. While the recent scholarship has done well in acknowledging moral remainder, the conversation has focused primarily on how these emotions might indicate the dilemmatic nature of the situations that produce them. In addition to reflecting on what moral remainder demonstrates about situations, this project will consider what these emotions reveal about the person who holds them. By guiding the dialogue in this direction, the project will expand moral dilemmas and moral remainder from abstract concepts into domains for the personal formation of virtue, namely, virtuous emotions. This development will take shape through attention to virtue ethics in conversation with insights from modern psychology to
articulate the role of emotion in the moral life. Together, these perspectives will promote a holistic understanding of emotions as essential to becoming virtuous amid the modern world’s increasingly complex moral landscape. I argue that such virtuous emotions take the shape of lament toward moral dilemmas that arise from natural causes and righteous indignation toward moral dilemmas that arise from unjust social systems.

Multiscale Mechanism of High Temperature Creep Deformation of Laser Powder Bed Fused Aluminum-Cerium Alloys

By generating nonequilibrium hierarchical microstructures, compositionally complex interfaces, and high dislocation densities, laser powder bed fusion (LPBF) offers a pathway to extending the elevated-temperature capability of aluminum alloys. In Al-Ce-based systems, rapid
solidification establishes a refined thermally stable intermetallics Al–Al₁₁Ce₃ architecture. Their thermal resistance alone, however, does not ensure creep strengthening, which also depends on reinforcement connectivity, obstacle effectiveness, and operative interfacial constraint, and matrix chemistry remain effective as recovery, diffusional redistribution, and boundary-localized deformation proceed.

This dissertation establishes an evidence-informed composition–microstructure–creep framework for LPBF pure Al, binary near-eutectic Al-10Ce, Zr-modified Al-10Ce-xZr (x = 0.3–1.0 wt.%), and hypereutectic Al-16Ce-1Mg by integrating compression-creep testing from 275 to
400 °C with multiscale characterization, kinetic and characteristic analyses, and experimentguided discrete dislocation dynamics (DDD) simulations. LPBF pure Al served as a processspecific matrix reference, enabling the effects of Al₁₁Ce₃ topology, Zr-related precipitation and grain refinement, and coupled Ce–Mg modification to be assessed relative to the unalloyed matrix.

Compared with LPBF pure Al, Al-Ce-based alloys exhibited remarkable creep resistance with lower minimum creep rates at higher applied stresses, yet this benefit was compositionally nonmonotonic and condition dependent. Moderate Zr addition improved creep resistance, whereas higher Zr and Ce additions provided no commensurate benefit, potentially reflecting the competing effects of strengthening, grain refinement, and diffusion-assisted deformation. These results reveal temperature-dependent kinetic competition among intragranular obstacle-dislocation strengthening, intermetallic-network reinforcement, and boundary-mediated accommodation. At lower and intermediate temperatures, the intermetallic architecture and dispersed particles contribute to an effective threshold resistance to dislocation motion. At higher temperatures, recovery, particle coarsening and increased spacing, loss of network connectivity, and localized damage weaken this resistance, while finer grains can facilitate a greater contribution from boundary-mediated deformation. DDD simulations further elucidate the coupled effects of stress, obstacle interactions, and dislocation evolution identifying nonuniform operative creep mechanism.

The central conclusion is that creep resistance in LPBF Al alloys depends not only on the thermal stability of constituent phases but also on the balance between the mechanical resistance sustained by reinforcement connectivity and spacing, matrix–solute interactions, and interfacial integrity within the hierarchical microstructure and the weakening effects of boundary-mediated transport and localized damage.

Enhancing Low-Temperature Anaerobic Treatment: Microbial Adaptation and Novel Technologies

Anaerobic biological treatment offers a potential alternative to aerobic treatment (e.g., activated sludge) to remove pollutants from municipal wastewater, with opportunities to reduce energy use and recover methane for renewable energy generation. However, slower microbial activity at low temperatures can limit anaerobic treatment performance. This dissertation examines how microbial acclimation, novel floating biofilm carriers (FBCs), and reactor design can improve anaerobic treatment of municipal wastewater at approximately 24 °C, which requires less heat energy and is lower than the traditional temperature of 35 °C.

First, long-term acclimation to the low temperature of biomass from two inoculum sources was evaluated to determine its effects on microbial communities and the kinetic parameters for acetate and hydrogen utilization, key parameters in anaerobic treatment. Acclimation increased acetate utilization rates in both inocula, while the response of hydrogen utilization differed between inoculum sources. Their microbial communities also developed differently, showing that inoculum source can influence how biomass adapts to colder temperatures.

Second, four 3D-printed FBC formulations were compared for their effects on organic matter removal and methane production. Incorporating beneficial materials into the carriers increased methane production and improved treatment performance compared to the control carrier without added material to the plastic, although the extent of improvement differed among material
formulations.

Third, select FBCs were evaluated in a novel downflow floating filter configuration treating synthetic primary effluent, and a hydraulic retention time comparable to activated sludge treatment was achieved. The novel configurations resulted in organic matter removal from the wastewater, but additional treatment was needed to reduce suspended solids in the final effluent. Membrane filtration, cloth-media filtration, and chemically enhanced clarification were therefore compared as post-treatment options.

QUANTIFYING THE EFFECTS OF HIGH INTENSITY GAIT TRAINING ON GAIT STABILITY IN PEOPLE WITH MULTIPLE SCLEROSIS

This dissertation characterizes symptom exacerbation and recovery following highintensity gait training (HIGT) in people with multiple sclerosis (PwMS). PwMS may experience more prolonged exercise-related side effects than individuals with other neurologic disorders. A better understanding of these side effects and their recovery may guide session scheduling and patient education to improve participation in HIGT for PwMS. HIGT is a task-specific intervention designed to optimize locomotor gains, but it may exacerbate symptoms to a greater degree than other modes of exercise due to larger increases in core temperature (TC) and transient slowing of conduction in demyelinated neuronal tracts. Characterizing the physiologic
mechanisms underlying symptom exacerbation and their subsequent recovery may help clinicians better anticipate post-HIGT responses and optimize session scheduling and patient education to support continued participation in this intervention.

Aim 1 quantified the impact of HIGT on somatosensory evoked potential (SSEP) latencies, a measure of neural conduction, and assessed which physiologic factors were associated with this change. SSEP latencies increased during HIGT for PwMS but quickly recovered back to baseline. These increases were not associated with the change in TC. Aim 2 examined changes in gait and reactive balance during and after HIGT, and assessed whether these changes were associated with physiologic responses. HIGT produced transient impairments in gait quality which resolved within two hours, while reactive balance was preserved. Greater increases in SSEP latency were associated with greater gait variability and impaired perturbation recovery, whereas greater increases in TC were less consistently associated with changes in gait and reactive balance. Aim 3 examined the impact of HIGT on community ambulation, activity, and symptomatic fatigue. HIGT temporarily reduced optimal community gait performance, while typical gait performance, overall activity, and symptomatic fatigue were largely unaffected. Collectively, these findings demonstrate that although HIGT produces measurable physiologic changes accompanied by alterations in laboratory and community gait, these changes are transient and do not lead to persistent side effects for PwMS with mild disease severity. Because changes in physiology and function after HIGT were heterogeneous, future research should continue to delineate who may be at greater risk for the development of post-HIGT side effects.

A COMPUTATIONAL FRAMEWORK FOR RISK, DIAGNOSTIC TIMING, AND EXPOSURE ANALYSIS OF DELAYED SLEEP APNEA DIAGNOSIS IN EHRS

Obstructive sleep apnea (OSA) affects nearly one billion adults worldwide, yet most cases remain undiagnosed while cardiometabolic harm accumulates. In electronic health records (EHRs), an OSA diagnosis appears only after symptoms are noticed, care is sought, and sleep testing is completed. It therefore reflects both disease and the opportunity for detection. Most studies and machine learning models treat the recorded code as the disease and ask whether it occurs, not when, potentially learning who has been seen rather than who is ill.

This dissertation addresses that gap by treating documented OSA as a delayed and selectively observed outcome. Using longitudinal EHR data from the Froedtert Health system, it compares General, COVID-only, and Long COVID cohorts, with COVID-19 providing a contrast in contact with care. A unified framework links machine learning, survival analysis, propensity-score weighting, post-index attenuation, and phenotype
discovery.

Predictive models achieved ROC-AUC values of 0.715 to 0.829. Age-sex-standardized diagnosis proportions were similar in COVID-only and General patients (10.44% and 10.85%) but higher in Long COVID patients (19.24%). One-year cumulative diagnosis was 8.52%, 15.14%, and 26.30%, respectively, with most differences emerging within 30 days. After measured-confounding adjustment, COVID-only exposure remained associated with earlier diagnosis (hazard ratio 1.634). Post-index clinical contact attenuated this association by up to 44.6%, and the strongest phenotype-specific association occurred among low-burden patients with little prior care (hazard ratio 2.071).

These findings indicate that COVID-related care may accelerate OSA recognition or documentation rather than uniformly increasing disease burden. Clinically, the work identifies the first month after COVID-related care as a high-yield window for sleep evaluation, highlights low-burden patients whom conventional screening may miss, and supports sleep assessment in Long COVID clinics. For public health, the framework can guide targeted screening, earlier case identification, and preventive-resource allocation among populations with limited healthcare contact. For clinical AI, it helps prevent healthcare access and documentation patterns from being interpreted as biological risk. This observation-aware approach can extend to other late-recognized conditions, including heart failure, chronic kidney disease, diabetes, and hypertension, supporting equitable surveillance and clinical decision-making.