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Elementary teachers' changes in formative assessment knowledge and classroom practices after participating in a professional development program : an embedded single-case study.
No full textU. S. educational policies focused on the use of high-stakes standardized achievement tests and top-down accountability to improve student achievement have had an insignificant impact. Furthermore, the focus on once-a-year standardized tests to measure student success negatively impacts daily classroom instruction and assessment practices. However, when classroom teachers consistently and effectively implement the formative assessment process in mathematics instruction, it has a positive impact on student learning. The formative assessment process is a complex pedagogical practice, and traditional professional development models do not support classroom implementation in a way that impacts student achievement. Therefore, there is a need to develop effective and sustainable training models that support teachers in implementing formative assessment processes into classroom practice. The purpose of this qualitative embedded single-case study was to explore how participants describe changes in formative assessment knowledge and classroom practices after participating in a learner-centered professional development. The formative assessment process is difficult for teachers to implement, and using a qualitative embedded single-case study design allowed me to investigate a complex phenomenon in a real-world context. Four elementary school teachers from different grade levels engaged in a six-week professional development program on the formative assessment process in mathematics instruction. The theoretical framework based on the constructivist theory of learning (Dewey, 1938) guided the research questions, as well as the data collection and analysis. I collected and analyzed qualitative data using observations, interviews, and artifacts. The findings revealed that participants perceived certain components of the professional development program supported their application of formative assessment knowledge into classroom practice. As a result of participating in the professional development program, participants developed a new understanding of the purpose and importance of the formative assessment process within mathematics instruction. Furthermore, teachers felt more confident and successful with their mathematics instruction when they planned and focused on the formative assessment process. The findings provide evidence for districts and instructional leaders about the design of effective professional development models that support teachers in their application of formative assessment knowledge into classroom practice
Virtual presence abjection : the rhetorical powers and dangers of horror in virtual reality.
No full textHorror has long been studied for its cultural commentary and deep cultural resonance in many different forms of media, even video games. Virtual reality games have also become a popular topic of cultural analysis for the sense of presence, or ‘really being there,’ that they can generate. At the intersection of horror and virtual reality, however, is a unique rhetorical potency that has largely been left unexamined. In this thesis, I will analyze and compare two virtual reality games with horror elements to highlight both the positive and negative ideological potential of horror in virtual reality. In order to do so, I will analyze using a theoretical lens that I refer to as virtual presence abjection, which is intended to account for both sides of this rhetorical intersection
Thermomechanical processing optimization and property enhancement of additive friction stir processed AA7075 through parameter driven strategies and heat treatment.
No full textDue to U.S. ITAR security compliance restrictions, this dissertation is not available. The abstract is available as an Unclassified Unlimited Release, NSC-614-7327, granted on 07/2025.Legacy aluminum alloys like AA7075 remain vital to aerospace applications due to their exceptional strength-to-weight ratios and established certification pathways. While fusion-based additive manufacturing techniques offer design flexibility, they often induce detrimental defects in these alloys including porosity, hot cracking, and volatilization of strengthening elements. Solid-state manufacturing approaches circumvent these limitations by operating below the melting point, preserving alloy composition and microstructural integrity while still enabling geometric complexity. This dissertation investigates Additive Friction Stir Deposition (AFSD), a solid-state technology that leverages severe plastic deformation and frictional heating to produce fully-dense aluminum components without phase transformation.
The research progresses through three interconnected investigations that establish fundamental process-structure-property relationships for AA7075 processed via AFSD. The work begins by examining the influence of heat input and deposition pitch on achieving isotropic tensile behavior, introducing the novel "Heat Pitch" metric that unifies thermal and mechanical aspects of processing into a single predictive parameter. This unified metric successfully identified critical processing conditions where isotropic mechanical properties emerge in as-deposited material, demonstrating build direction ductility improvements from 6% to 27% through parameter optimization guided by Heat Pitch values. The findings establish a quantitative framework for tailoring processing parameters to achieve targeted mechanical performance in solid-state additively manufactured components.
Building on these findings, the second investigation develops lubricant-free Twin Rod AFSD processing strategies utilizing continuous helical deposition paths. This approach demonstrates that even with identical temperature setpoints, mechanical property development follows distinct pathways governed by thermomechanical conditions, achieving exceptional build direction ductility in thin-walled structures despite processing constraints.
The final investigation establishes that conventional heat treatment protocols can transform additively manufactured AA7075 to achieve aerospace-grade mechanical properties. Post-deposition heat treatment increases yield strength from 199 MPa to over 460 MPa in the build direction, demonstrating that solid-state additive manufacturing, combined with appropriate post-processing, can produce components with properties comparable to conventional forgings in their limiting design orientation.
This research provides foundational understanding of how processing parameters influence microstructural evolution and mechanical performance in solid-state additive manufacturing, establishing pathways for implementing AFSD in critical structural applications where build direction properties typically represent design limitations
Novel methods for organic synthesis : exploring organocatalytic dihalogenation, palladium mediated cross-coupling, and zirconium catalyzed transformations.
No full textThis dissertation explores the development of novel methods for the organocatalytic heterodihalogenation of unsaturated systems, Suzuki cross-coupling, and zirconocene hydride-mediated catalysis. The increasing discovery of naturally occurring organohalogenated compounds has fueled our interest in selective halogenation methods. To date, approximately 8,400 of these compounds have been discovered, with many polyhalogenated compounds possessing potent biological activity. Compounds possessing vicinal bromochlorides inspired us to develop a mild, metal-free protocol for the bromochlorination of alkenes, alkynes, dienes, and allenes. We developed a Lewis base-catalyzed method, utilizing PPh3 or OPPh3, to activate SOCl2, providing the release of our nucleophilic chloride source. In addition, this reaction was rendered enantioselective on aryl enones with the implementation of chiral cinchona alkaloid derived catalyst, (DHQD)2PHAL, to afford the bromochlorinated products in up to 92:8 er. We further investigated the synthetic utility of dihalide products of allenes, which undergo a series of diversifications leveraging the orthogonal reactivity of the respective halides. During an experiential internship at AbbVie, we developed a strategy for the Suzuki-Miyaura cross-coupling of ortho-bromoanilines with boronates. Ortho-bromoanilines are prevalent in several pharmacologically active compounds, and few methods in the literature allow for the direct coupling of these 2-haloanilines, without prior protection of the functional group. This palladium-catalyzed protocol allowed for the coupling of benzyl, alkyl, alkenyl, aryl, and heteroaromatic substrates, in addition to the forging of C(sp2)-C(sp3) bonds to facilitate towards the preparation of a compound library. Finally, our lab has a vested interest in developing methods using zirconocene-hydride catalysis. In the final chapter of this dissertation, early efforts on the development of a mild, catalytic transformation of esters to nitriles will be discussed. Due to the high abundance of Zr(IV) compounds, their low toxicity, low cost, and similar orthogonal reactivity to many late transition metals, zirconium has proven to be an excellent choice for catalytic applications. This unique transformation employs acetonitrile as both the solvent and nitrogen source in the reaction and supports aliphatic, aromatic, benzyl, a-substituted, and acrylate functional group classes. Early investigations of the mechanism are discussed
Longitudinal measurement invariance of Christian scales.
No full textIn this dissertation, I discuss the importance of measurement invariance using two examples of Christian scales, the Christian Orthodoxy Scale and the Faith Maturity Scale. Measurement invariance is one of the critical elements of latent mean comparisons. Without the establishment of invariance models, there is a lack of evidence that the findings truly reflect differences in the construct(s) instead of an artifact of measurement errors. Using longitudinal data of college students across four time points, the confirmatory factor analytic methods were employed to test several invariance models, configural, metric, scalar, and strict models. In paper one, the scalar invariance model was supported suggesting that the conceptual meaning of Christian Orthodox belief was consistent across time with supportive evidence that the latent trajectory can be examined. In paper two, the strict invariance model was established also suggesting that the latent scores of vertical and horizontal faith maturation can be tested longitudinally. In the final chapter, I also discuss some of the recently developed invariance testing procedures including the moderated non-linear factor analysis along with the discussion about philosophical marginalization in modern latent variable modeling
Childhood adversity and health along the life course : nuances of a complex relationship.
No full textThe effects of childhood adversity reach far past childhood, with implications across the life course. A rich body of literature has established a strong theoretical base for the link between childhood adversity and health, and has provided empirical evidence for the impact of childhood adversity on numerous health outcomes. Nonetheless, our understanding of this relationship lacks nuance. Notably, patterns in which experiences of childhood adversity co-occur and subsequently impacts health remain unclear. This dissertation utilizes data from the National Longitudinal Study of Adolescent to Adult Health (Add Health) to uncover unique patterns of adverse childhood experiences (ACEs) in a large, nationally representative sample of American adolescents. Using a comprehensive set of ACE measures, latent class analysis is executed to produce four distinct ACE classes, and respondents are assigned to their most likely class. Additionally, this analysis assesses the relationships between ACE class and both mental and physical health outcomes. The first empirical chapter uncovers distinct patterns of ACEs that tend to co-occur. Latent class analysis derives four ACE classes: Low Adversity, Parental Hardships, Aggression, and High Adversity. Analyses stratified by gender reveal that these patterns do not vary greatly by gender. The second chapter uses these constructed ACE classes to predict clinical anxiety and depression diagnoses along the life course. Findings from this analysis indicate that membership in the Aggression and High Adversity classes are associated with higher odds of anxiety and depression. Results vary when analyses are stratified by gender. The third chapter focuses on physical health and measures c-reactive protein, which is an indicator of inflammation. Findings indicate that the relationship between ACE class and c-reactive protein is attenuated by covariates. Overall, this dissertation builds on prior ACE-health literature to uncover nuance between patterns of adverse childhood experiences and health outcomes along the life course
God’s plan, God’s community? : divine control, congregational and spiritual support, and the association with subjective well-being in the United States.
No full textDivine control, the belief that God exerts authority over the course of one’s life, is an important religious cognition with robust connections to mental health. Despite this empirical basis, few studies have sought to understand why divine control is favorable for subjective well-being. This study expands the literature by considering the relationship between divine control and life meaning, optimism, and life satisfaction while integrating perceived congregational and spiritual support. Drawing on data from an original survey of congregants (N = 1,556) collected in 2017-2019 from San Antonio and Washington DC, regression results suggest that greater divine control predicted greater subjective well-being. Parametric mediation results suggest a consistent pattern of mediation, where both congregational and spiritual support partially explained the association. We situate our findings within the growing body of research on religious cognitions, like divine control, in the social psychology of religion and emphasize the importance of the religious community
Artificial intelligence : a single case study exploring how secondary teachers integrate artificial intelligence into their teaching practices.
No full textIntegrating artificial intelligence (AI) into secondary education, grades 6–12, presents both opportunities and challenges for teachers. Limited research exists on how secondary educators perceive AI’s role in their classrooms, making it critical to explore their experiences and perspectives. As educators increasingly adopt AI tools, understanding their perceptions of this technology is essential. The integration of AI in the classroom can provide teachers with innovative tools and strategies to enhance their instructional approaches, but it also requires them to navigate the complexities of implementing new technologies and adapting their teaching methods accordingly.
The purpose of this single case study was to explore how secondary teachers perceive they integrate artificial intelligence into their teaching practices based on their technological knowledge, pedagogical knowledge, and content knowledge. Using a qualitative single case study design, the research involved a questionnaire, individual interviews, a focus group discussion, and artifact collection from four secondary teachers within a Texas school district. The technological pedagogical and content knowledge (TPACK) framework served as the theoretical framework of this study (Mishra & Koehler, 2006).
I uncovered six findings. First, participants perceived AI as a valuable tool for differentiation, enhancing their ability to blend technological, pedagogical, and content knowledge in ways that meet diverse student needs. Second, participants perceived AI as an essential resource for enhancing classroom organization and efficiency, leveraging technological knowledge to streamline planning, grading, and administrative tasks while supporting pedagogical effectiveness. Third, participants perceived AI supports them in developing personalized and adaptive instructional strategies, effectively integrating content knowledge with technological tools to meet student learning levels and align with standards. Fourth, participants perceived that AI enhances content knowledge application by helping them align instructional materials with curriculum standards. Finally, participants perceived that AI continues to shift their roles as instructors toward becoming facilitators, providing students with tools for self-directed learning and reducing the need for direct instruction. Sixth, participants perceived that there is a need to balance AI-generated content with their professional expertise, highlighting the importance of blending technological tools with pedagogical and content knowledge
Posttraumatic growth-oriented training outcomes : evaluating active military and first responder populations.
No full textTrauma exposure among military service members and first responders occurs at a high rate, with approximately 87% of U.S. veterans and 80% of first responders reporting exposure to at least one potentially traumatic event. There is a need for trauma-focused intervention in these populations which engages clients, provides prompt and lasting effects, and addresses existential matters faced by them. Posttraumatic growth training, such as the Boulder Crest Warrior PATHH program, has been illustrated to be effective in promoting growth and reducing symptomatology (i.e., PTSD symptoms, depression, anxiety, stress, and insomnia) at both immediate and 18-month follow-up in veteran populations. The current dissertation documents the effects observed in active military and first responder populations who have completed the Warrior PATHH 5.0, the latest iteration of the program. It presents effects on posttraumatic growth and symptomatology similar to those observed in veteran populations, providing support for generalizability of the Warrior PATHH program
Plasma puzzle : how temporal and spatial variations shape dust self-structuring.
No full textIn dusty plasma systems, negatively charged dust grains are observed to self- organize into stable structures. In this work, a multiscale numerical model known as the Dynamic Response of Ions and Dust (DRIAD) is used to determine the effect that temporally and spatially evolving plasma parameters have on dust grains immersed in a plasma. The work is divided into three different studies: the effect of electron number density variations on a one-dimensional seven-grain dust chain, the impact of spatially varying electric fields on two-dimensional dust structures, and the influence of temporally evolving plasma conditions on dust chains in microgravity, specifically aboard the PK-4 experiment on the ISS. The first study demonstrated that decreasing electron density in the sheath region led to stronger electric fields and reduced dust chain stability. The second study examined the interaction between vertical and horizontal confinement forces, showing that an increased vertical confinement led to increased chain stability while the increased horizontal confinement led to a reduced stability. The third study focused on time-varying plasma conditions, showing that oscillating fields and changing densities significantly alter dust charging and ion wakes, promoting chain formation