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ASSESSMENT OF THE DYNAMIC RELATIONSHIP BETWEEN HIGH AND LOW PREFERENCE STIMULI AND RESPONDING IN EARLY INTENSIVE BEHAVIORAL INTERVENTIONS FOR CHILDREN WITH AUTISM SPECTRUM DISORDER
Get PDFThesis (M.A.)--Michigan State University. Applied Behavior Analysis - Master of Arts, 2025With the growing number of Autism Spectrum Disorder (ASD) diagnoses, Applied Behavior Analysis (ABA) has become a widely accepted and evidence-supported method for early childhood intervention. Within ABA interventions, the effective use of reinforcement strategies is crucial for successful outcomes, particularly in skill acquisition and behavior maintenance. This study investigated the effectiveness of high-preference (HP) and low-preference (LP) stimuli as reinforcers for young children diagnosed with ASD. Utilizing a multiple baseline design across participants, this study included three children diagnosed with ASD, aged 2 to 5 years, in a community-based early intensive behavioral intervention setting. Reinforcer effectiveness was evaluated using progressive-ratio (PR) schedules following paired-choice preference assessments to identify edible reinforcers. Results demonstrated that HP stimuli consistently achieved higher breakpoints, indicating stronger reinforcement effects. However, LP stimuli also effectively maintained participant responding, although with comparatively lower breakpoints. These results highlight LP stimuli's viability as reinforcers, particularly when HP stimuli are limited or unavailable. The findings offer practical implications for ABA practitioners, suggesting that LP stimuli can support skill acquisition and maintain behaviors effectively under specific conditions. This study contributes to refining reinforcement practices, enabling more versatile and individualized ABA interventions for young children with ASD. Key words: reinforcement, progressive-ratio, high preferred reinforcer, low preferred reinforcerDescription based on online resource. Title from PDF t.p. (Michigan State University Fedora Repository, viewed ).Includes bibliographical references
A SYSTEMIC EXPLORATION OF AGRICULTURE TEACHER RETENTION AND IDENTITY DEVELOPMENT
Get PDFThesis (Ph.D.)--Michigan State University. Community Sustainability-Doctor of Philosophy, 2025A teacher shortage exists across a multiplicity of educational disciplines, including school-based agricultural education. A breadth of research has been conducted on teacher retention within agricultural education, with many studies focusing on agriculture teachers and their experiences with retention or attrition. To extend the scholarship on agriculture teacher retention, we must better understand teacher retention within school, community, and discipline contexts, as agriculture teachers are key components of these communities. Relatedly, the immense number of interconnections within these diverse contexts necessitate a systems-thinking approach. As such, I employed a context-based, system dynamics approach to glean new insights on agriculture teacher retention. Through three interrelated studies, this dissertation employs the theory of margin and landscapes of practice theory to explore teacher workloads, boundary setting, and identity formation. The methodologies employed in these articles vary; the two empirical studies take a qualitative approach, with the latter being conducted via a participatory partnership. The non-empirical, philosophical contribution centers system dynamics modeling, created via researcher experience and a literature review. Taken in combination, these studies reveal interconnections between teachers and their contexts, insights into retaining teachers across career stages, and strategies teachers use to cope with the workload of being effective educators. Collectively, these studies illustrate ways incorporating systems thinking may provide additional insights into the teacher shortage, including seeing the bigger picture, creating models, and providing language for phenomena such as the noble sacrifice mindset. New perspectives on agriculture teacher retention include the importance of context-based research, the impact of community support on teacher workload and identity development, and the teacher-supporter-community interface. These findings contribute to a more holistic perspective of agricultural education and teacher retention. Future directions for research include continued context-based, systemic research, especially within various communities with diverse socio-cultural-historical backgrounds and with teachers who have marginalized identities.Description based on online resource. Title from PDF t.p. (Michigan State University Fedora Repository, viewed ).Includes bibliographical references
THE ROLE OF NITROGEN ASSIMILATION IN CELL CYCLE CONTROL OF CAULOBACTER CRESCENTUS
Get PDFThesis (Ph.D.)--Michigan State University. Microbiology and Molecular Genetics - Doctor of Philosophy, 2025Bacteria rely on complex regulatory networks to coordinate growth, development, and environmental adaptation. In Caulobacter crescentus, cell cycle progression is tightly controlled by the essential CckA-ChpT-CtrA two-component signaling phosphorelay. CckA, a bifunctional sensor histidine kinase (SHK), regulates the phosphorylation state of CtrA, a master response regulator (RR) that directs the transcription of over 90 genes involved in cell cycle progression, cell division, and polar morphogenesis. The activity of CckA is influenced by intracellular signals such as cyclic-di-GMP and ADP, as well as environmental stress cues that enhance its phosphatase activity. Altogether, regulation of CckA kinase/phosphatase activity leads to the properly timed oscillation of CtrA inactivation and degradation during each cell cycle, as well as a block in cell division under stress. Despite the essential nature of CckA and CtrA, genetic studies have identified alternative pathways that can bypass the requirement for CckA function, highlighting the flexibility of the C. crescentus regulatory network. In this dissertation, I demonstrate that the bacterial enhancer binding protein (bEBP) NtrC, and its cognate SHK, NtrB, play critical but previously unrecognized roles in coordinating nitrogen metabolism with cell cycle progression and development in C. crescentus. NtrC is an unconventional bEBP that lacks the conserved GAFTGA motif required for \u3c354-RNA polymerase activation. I show that deletion of ntrC slows growth in complex medium and that ntrB and ntrC are essential when ammonium is the sole nitrogen source due to their requirement for glnA expression. Interestingly, spontaneous insertion of an IS3-family mobile genetic element frequently restored the growth defect of ntrC mutants by reactivating transcription of the glnBA operon, suggesting that IS3 transposition may play a role in evolutionary adaptation of C. crescentus to nutrient limitation. Genome-wide binding studies within this work identified numerous NtrC binding sites near genes involved in polysaccharide biosynthesis and cell cycle regulation, often overlapping with binding sites for the essential nucleoid-associated protein GapR and the cell cycle regulator MucR1. Loss of NtrC function resulted in elongated polar stalks and increased synthesis of cell envelope polysaccharides, implicating NtrC in the direct regulation of cell morphogenesis and development. Furthermore, genetic suppression of a temperature-sensitive cckA mutant revealed that mutant forms of NtrC can bypass the essential CckA-ChpT-CtrA phosphorelay through two mechanisms: 1) increased levels of the alarmone ppGpp due to intracellular glutamine limitation, which sustain CtrA protein levels, and 2) activation of transcription at select \u3c354-dependent promoters despite the absence of the GAFTGA motif. My results presented in this dissertation provide evidence that NtrC can function as a central integrator of nitrogen status and cell cycle progression in Caulobacter, linking nutrient availability with core developmental processes. My discovery of ntrC mutants that rescue cckA loss-of-function highlights the remarkable plasticity of bacterial regulatory networks and underscores the complex interplay between nitrogen metabolism, nucleotide signaling, and cell cycle control. This work establishes NtrC as a key regulator of cell cycle progression and developmental plasticity in C. crescentus, revealing new insights into the adaptive potential of bacterial signaling pathways.Description based on online resource. Title from PDF t.p. (Michigan State University Fedora Repository, viewed ).Includes bibliographical references
ENCOUNTERING THE COLOMBIAN STATE\u2019S DUTY TO REMEMBER : THE COLOMBIAN NATIONAL POLICE AND ITS WINDOW TO THE PAST
No full textThesis (Ph.D.)--Michigan State University. Anthropology - Doctor of Philosophy, 2025This dissertation ethnographically explores the Colombian National Police's encounter with the state\u2019s duty to remember. In other words, this work studies the encounter between police agents rejecting the label of human rights abusers and official and unofficial collectivities seeking to hold state security institutions accountable for historic forms of abuse against civilians and activists. The exploration this dissertation provides is the product of 13 months of fieldwork in Colombia. In five of those months, I conducted participant observation in the Police Unit of Peacebuilding (UNIPEP), a recently created subdivision in the police with a \u201cpeacebuilding\u201d mandate. However, it also has a mandate to build a historical narrative of the police that could represent it as legitimate, victorious, and transparent. UNIPEP\u2019s historical memory mandate has produced material and symbolic cultural expressions that illuminate the way the police encounter criticism from other institutions of the state and justice seekers. This dissertation analyzes the material and symbolic expressions of the police encounter with the state\u2019s duty to remember by focusing on three critical dimensions: its historical context, the content of the police\u2019s memory products, and the police's endogenous memory players' search for legitimacy. This dissertation starts with an unshakable assumption: the police memorialization of the conflict is a socio-cultural development that cannot be adequately understood without accounting for the Colombian transitional period, marked by the profound influence of human rights culture in politics and the introduction of transitional justice institutions. Following the work of scholars like Winifred Tate, Juan Ricardo Aparicio, and Alejandro Castillejo, this dissertation traces the introduction of human rights grammar in Colombia, but with a focus on its role in the documentation and memorialization of violence. Closer to Steve Stern and Elizabeth Jelin\u2019s theoretical and methodological frameworks to make sense of collective memories and memory politics, this dissertation explores the chronology of memory and politics, establishing that the police memorialization of the conflict and its role in it is just one expression of a larger reaction to human rights memories and their institutionalization between 2005 and 2025. The larger reactionary politics that the police are making a part of, which is not characterized by strict denialism, demonstrate that reactionary movements in Colombia are appropriating human rights grammar to contest calls for accountability made by a significant number of victims of human rights violations. The contestation that the police are a part of is creating a new reactionary framework of meaning that questions the plural approach taken by transitional justice institutions in their mandate to clarify the past and to serve justice. This dissertation confirms the reactionary imprint of the police memorialization of the conflict by studying the memory products it has mobilized as the police's \u201ccontribution to historical memory.\u201d It includes the analysis of memory sites, books, and documentaries that the police incorporate as part of their \u201cinstitutional historical memory,\u201d concentrating on the representation of police agents as heroes and victims of the conflict. The allusion to the police victimhood is interpreted as an update of the police collective identity, one that revises the meaning of heroism to include suffering and injustice as part of the everyday life experience of police agents at different hierarchical positions during the conflict. But, following the concerns police agents communicated during my fieldwork, victimhood is also interpreted as a problematic concept with multiple connotations that not every police agent is willing to accept. Overall, the exclusive concern for representing police agents as heroes and victims of the conflict cannot be separated from the chronology of memory and politics. The reactionary attitudes held by powerful elites invite police agents to interpret that, when it comes to memorializing the past, sidestepping institutional responsibilities for human rights violations is better than facing the complexity and bitterness of truth. The dissertation finishes by discussing how the police's endogenous memory players sought legitimacy for their memory initiatives, focusing on the role that outside experts have had in the police's \u201cinstitutional historical memory,\u201d and how the value-free ideal is mobilized by the police when publicizing their memory products. This discussion engages critically with the police's claims of \u201cimpartial memorialization.\u201d At the same time, it also demonstrates that the police's memorialization also comes from ahistorical but still human rights-informed perspectives that outside experts have. In other words, my discussion shows that the police's memorialization of the past is not only a strategic development or a systematic form of denial, but an outcome of a society where human rights culture is dominant, and where multiple actors embedded in it try to navigate the murky configuration of Colombian violence and its truth.Description based on online resource. Title from PDF t.p. (Michigan State University Fedora Repository, viewed ).Includes bibliographical references
EFFECTS OF ACUTE AEROBIC EXERCISE ON NEURAL INDICES OF EMOTION REGULATION AND COGNITIVE CONTROL IN INDIVIDUALS WITH PTSD SYMPTOMS
Get PDFThesis (Ph.D.)--Michigan State University. Psychology - Doctor of Philosophy, 2025Posttraumatic Stress Disorder (PTSD) is associated with emotion regulation difficulties and cognitive control deficits, which may exacerbate symptoms and negatively affect treatment outcomes. Cognitive emotion regulation strategies, such as cognitive reappraisal, can be especially challenging for individuals with PTSD due to heightened attentional bias toward negatively arousing stimuli and limited cognitive resources needed to regulate their emotional response. Therefore, it is crucial to identify alternative strategies that target both emotion regulation and cognitive control in PTSD. Aerobic exercise has emerged as a promising alternative intervention to target emotion regulation and cognitive control. However, research on the acute effects of exercise on these mechanisms in PTSD populations is limited. This study investigated the acute effects of a single bout of moderate-intensity aerobic exercise on subjective (e.g., self-reported emotional arousal) and neural (e.g., LPP) indices of emotion regulation, as well as behavioral (e.g., flanker task accuracy and reaction time) and neural (e.g., P300 and ERN) indices of cognitive control in individuals with clinically significant PTSD symptoms. Using a within-subject, pre- to post-test crossover design, 67 female participants completed a 20-minute moderate-intensity aerobic exercise session and a 20-minute time-matched sitting control session. Prior to and following each experimental session, participants completed an emotion regulation task and a letter flanker task to measure emotion regulation and cognitive control, respectively. I hypothesized that exercise would 1) enhance cognitive control \u2013 evidenced by increased P300, decreased ERN, and improved behavioral performance; and 2) improve emotion regulation \u2013 evidenced by decreased LPP and perceived emotional arousal during cognitive reappraisal. Lastly, I predicted improvements in cognitive control would mediate the effect of exercise on cognitive reappraisal success. Contrary to predictions, exercise did not lead to significant changes in P300 or ERN amplitudes during the flanker task, relative to sitting. Behaviorally, although no significant difference in response accuracy was observed, following exercise, participants demonstrated a greater reduction in reaction time relative to sitting, indicating more efficient performance. For the emotion regulation task, exercise led to a significant increase in the early and late LPP during cognitive reappraisal trials relative to view-negative trials. However, this effect appeared primarily driven by a significant decrease in LPP during view-negative trials from pre- to post-test. Exercise also did not lead to a significant change in perceived emotional arousal relative to sitting. However, exercise led to a significant decrease in perceived effort using cognitive reappraisal. Lastly, results from the mediation analysis did not support my hypothesis that exercise-induced improvements in cognitive control mediate the effect of exercise on cognitive reappraisal success. Overall, while acute aerobic exercise did not enhance neural markers of cognitive control and cognitive reappraisal success, reductions in LPP during view-negative and decreased perceived effort during cognitive reappraisal suggest that aerobic exercise may positively influence cognitive emotion regulation processes. These findings provide preliminary support for the use of exercise to enhance emotion regulation processes in PTSD. Future research is needed to further investigate the acute and long-term effects of exercise on emotion regulation and cognitive control in PTSD, as these insights may inform future research on exercise-augmented treatments for PTSD to enhance treatment outcomes.Description based on online resource. Title from PDF t.p. (Michigan State University Fedora Repository, viewed ).Includes bibliographical references
A ROLLING METHOD FOR CAUSAL INFERENCE : A FLEXIBLE ESTIMATION METHOD FOR DIVERSE PANEL DATA SETUPS
Get PDFThesis (Ph.D.)--Michigan State University. Economics - Doctor of Philosophy, 2025This dissertation develops new methods for estimating treatment effects using panel data, with a focus on flexible and robust identification under treatment effect heterogeneity across units and over time. Chapter 1 provides an overview of the subsequent chapters. Chapter 2 introduces a simple time-series transformation\u2014termed the Rolling Method\u2014for Difference-in-Differences estimation. This method converts panel data into a sequence of cross-sectional datasets through unit-specific outcome transformations, enabling consistent estimation of group-time-specific treatment effects even in the presence of treatment heterogeneity. Chapter 3 extends the Rolling Method to small-sample settings, particularly when the number of treated or control units is limited, and demonstrates improved finite-sample inference properties. Chapter 4 further generalizes the framework to accommodate dynamic treatment paths, allowing for treatment reversals and subgroup-specific moderating effects. This extension is applied in an empirical case study examining the effects of the entry and exit of chain pharmacies in rural areas.Description based on online resource. Title from PDF t.p. (Michigan State University Fedora Repository, viewed ).Includes bibliographical references
PEAK EXPERIENCES IN TRAVEL : EXPLORATION OF LASTING IMPACTS ON ATTITUDES TOWARDS SELF AND THE ENVIRONMENT
No full textThesis (Ph.D.)--Michigan State University. Sustainable Tourism and Protected Area Management - Doctor of Philosophy, 2025Travel has long been celebrated as a gateway to growth, learning, and transformation. Simply stepping outside of one\u2019s daily routine, encountering different landscapes and cultures, and experiencing a sense of newness can push individuals to reexamine their values, broaden their perspectives, and adopt new behaviors. But does travel really lead to such change? And if it does, what kind of travel produces lasting impacts\u2014and for whom?This dissertation addresses those questions by exploring the enduring impacts of emotionally significant travel moments \u2013 commonly referred to as peak experiences \u2013 on travelers\u2019 sense of self and their attitudes toward the environment. While the idea of travel as transformative is deeply embedded in both popular and scholarly discourse, empirical research has only recently begun to examine the long-term psychological and behavioral impacts of such experiences. Much of the existing literature remains focused on short-term outcomes, stated intentions, or anecdotal claims. Moreover, most research to date has centered on travelers themselves, with less attention given to other actors involved in the tourism process, such as facilitators and hosts. Drawing from three distinct qualitative studies, this dissertation investigates how such peak experiences are remembered and integrated over time. In doing so, it responds to existing gaps by incorporating the perspectives of both travelers and facilitators and by emphasizing retrospective reflection on peak experiences that occurred at least one year prior to data collection. The research is grounded in in-depth interviews with three distinct participant groups: 1) American undergraduate students who participated in a short-term study abroad program in Mozambique; 2) experienced international tour leaders reflecting on powerful moments from their guiding careers; and 3) wildlife tourists who experienced immersive in-depth encounters with whales. Collectively, these studies span a range of traveler profiles, cultural contexts, and tourism formats. They offer a multifaceted view of how emotionally charged, immersive travel can catalyze transformation in people\u2019s beliefs, behaviors, and relationships with the natural world. Findings across the three studies show that peak travel experiences can have profound and lasting effects on individuals\u2019 self-perception, emotional awareness, and environmental consciousness. Common themes include increased confidence and agency, a shift toward a more eco-conscious lifestyle, and a strengthened sense of connection \u2013 to themselves, others, and to nature. By adopting a retrospective approach and including diverse perspectives, this research advances our understanding of the psychological and behavioral afterlives of peak experiences in travel. It also highlights ethical and practical implications for tourism, education, and conservation practitioners who seek to design and support travel that is not only memorable, but meaningful \u2013 and that cultivates lasting change.Description based on online resource. Title from PDF t.p. (Michigan State University Fedora Repository, viewed ).Includes bibliographical references
USING STUDENT LEARNING OUTCOME DATA AT COMMUNITY COLLEGES : UNDERSTANDING THE HOW
Get PDFThesis (Ph.D.)--Michigan State University. Higher, Adult, and Lifelong Education - Doctor of Philosophy, 2025This study explores how a community college successfully implemented and sustained the use of student learning outcome (SLO) assessment data to improve institutional quality. Utilizing interpretivist exploratory case study methodology, the research examines a community college recognized for its excellence in assessment practices by the National Institute for Learning Outcomes Assessment (NILOA). The theoretical framework used to ground this research is Ivancevich et al.\u2019s (2014) Model of Organizational Change, while the conceptual framework utilized is Bolman and Deal\u2019s (2017) Four Frames Model. Data collection included semi-structured interviews with faculty, staff, and administrators.Findings from this study reveal three overarching themes critical to the success of the initiative: (a) managing conflict and resistance, (b) the role of integrated leadership in driving change, and (c) building a culture of assessment through collaboration and inclusivity. Practical implications emphasize the need for institutions to create systems of peer support, align assessment practices with institutional missions, and train leaders in multi-frame analysis to navigate organizational complexity. These findings provide actionable insights for institutions, similar to the one studied in this dissertation, striving to close the assessment loop and improve student success through evidence-based decision making.Description based on online resource. Title from PDF t.p. (Michigan State University Fedora Repository, viewed ).Includes bibliographical references
SPECIAL EDUCATION IN INDIAN COUNTRY : CONCEPTIONS OF DISABILITY, SPECIAL EDUCATION, SURVIVANCE AND REFUSAL
Get PDFThesis (Ph.D.)--Michigan State University. Anthropology - Doctor of Philosophy, 2025Indigenous students are disproportionately represented in special education programs in the United States, with 19% of them tracked into special education programs in public schools. Despite this fact, the intersection of Indigeneity and disability remains underexplored, offering a unique opportunity to develop frameworks that promote positive educational outcomes for Indigenous students. This dissertation examines how unique Indigenous cultural contexts intersect with experiences of systemic oppression to shape understandings of disability, special needs, and accommodations for Indigenous children in special education.During nine months of ethnographic fieldwork at a Tribal school in central Minnesota, situated within Anishinaabe territory, I explored how parents, guardians, and educators assessed the need for special education services, the factors influencing placement decisions, and the outcomes for students receiving services. I also observed the aids and accommodations provided to students in special education and how these supports were implemented in practice . I also interviewed students using a novel method that I developed for Indigenous children using art elicitation. The interview method was mostly successful with students being able to express aspects of themselves and identities in both visual media and in conversation. This method allowed them to communicate complex topics and ideas, which are otherwise difficult for them to vocalize. My dissertation integrates analytical framings from Indigenous education, disability critical race theory (DisCrit), and critical Indigenous theory in presenting several key themes. First, the concept of survivance, the continued existence and survival of Indigenous people in the face of colonialism, and refusal, the act of refusing settler colonial power, are useful for understanding educational environments. The Tribal school itself was created as an expression of both survivance and refusal, and these two concepts are also expressed by the families who attend the school. They express survivance by enrolling their children in a school that offers a culturally and community-based education, but they also express refusal in different ways, notably when elders reject or resist efforts to enroll children in their care in special education services. I emphasize the importance of trust and relationship-building with students and their families because of historical and contemporary trauma surrounding educational institutions. The legacy of trauma complicates the understanding and categorization of disability within the Tribal school context because, as I argue, there is an attempt to separate and make distinctions between students struggling with trauma and students struggling with disabilities, even though trauma and learning disabilities share similar symptomology. In this area, I argue that the focus on this distinction may lead to providing more effective interventions. It also challenges disability reductionism to instead engage more effectively with the long-term impacts of social issues affecting Indigenous peopleDescription based on online resource. Title from PDF t.p. (Michigan State University Fedora Repository, viewed ).Includes bibliographical references
EXPLORING THE FIRST-YEAR TRANSITION EXPERIENCES OF WOMEN DEPARTMENT CHAIRS
Get PDFThesis (Ph.D.)--Michigan State University. Higher, Adult, and Lifelong Education - Doctor of Philosophy, 2025Gmelch and Mishkin (2004) shared that \u201chigher education will continue to have a \u201cleadership crisis\u201d as long as chairing a department remains an unmanageable and unproductive option for faculty members\u201d (p. 132). For a role that has been referred to as a lynchpin in the university (Cipriano, 2011), faculty often try to avoid the chair role because they do not want to deal with the stress of the role or have to worry about falling behind in their research. For many individuals who assume the chair role, this is their first foray into leadership. While faculty are trained to be leaders in their disciplines, very few are prepared with the skills they need to step into formal leadership roles.Over the last few decades, the number of women receiving doctoral degrees has reached gender parity, yet the number of women advancing into academic leadership roles has not experienced the same growth. As individuals stepping into the chair role may already experience a shift in identity from faculty to leadership, this study focused on understanding how women perceived their transition from faculty to chair. Eight women department chairs were identified from a conference of R1 institutions and participated in this qualitative study examining the challenges and successes of their lived experiences throughout their first-year in the role. Schlossberg\u2019s Transition Theory combined with Gmelch and Buller\u2019s Framework for Developing Academic Leaders guided the data collection. Narrative analysis was used to examine stories the women chairs shared and identify common themes. The experiences the women shared were diverse; however, the most common theme they all discussed related to the transition being a time of learning. While initial conversations focused on learning specific tasks and responsibilities of the job, the learning process extended to self-discovery for the women around who they are as leaders and how their first-year experience developed their leadership capacity. In addition to learning traditional aspects of the chair role, the women and those who held additional intersecting minoritized identities found they had to learn how to manage the hidden work related to age, race, or ability. Analyzing the stories of the women chairs revealed several implications for approaches to help make the role more manageable by initiating new learning strategies and exploring how the role could be reimagined. This study provides recommendations for those in institutional leadership roles, current faculty development practitioners, and for the new chairs themselves. While women were the focus of the study, suggestions discussed have implications for anyone stepping into a department chair role.Description based on online resource. Title from PDF t.p. (Michigan State University Fedora Repository, viewed ).Includes bibliographical references