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11Be SPECTROSCOPY FROM THE FIRST INVERSE KINEMATICS TRANSFER REACTION MEASUREMENT BY THE AT-TPC IN SOLARIS
No full textThesis (Ph.D.)--Michigan State University. Physics - Doctor of Philosophy, 2025As evidenced by the field\u2019s existence surpassing a 100 years, nuclei are varied and immensely complex. New accelerator facilities are now able to produce rare isotopes that seldom appear in nature and whose properties must be measured to lead to a better understanding of the nuclear force. These facilities have naturally facilitated the need to switch to inverse kinematics. This, coupled with the low intensity of rare isotope beams, has lead to the creation of a new type of detector called an active target. These detectors are especially well-suited for rare isotope beams due to their high luminosity, theoretical 4? solid angle coverage, and ability to determine the vertex of a nuclear reaction.One such active target is the Active Target-Time Projection Chamber (AT-TPC) housed at the Facility for Rare Isotope Beams. This thesis reports the results from the first transfer reaction measurement by the AT-TPC in inverse kinematics. Specifically, 11Be spectroscopy was performed via the 10Be(?, ?) reaction. 11Be is an ideal candidate for such a commissioning measurement as the structure of its low-lying states is well known, allowing for comparisons to the literature. Despite this, the parity of its fourth excited state at 3.40 MeV has been debated. This thesis measured the angular distributions of all states in 11Be up to and including this state. Their spectroscopic factors were derived and compared to values in the literature and theoretical shell-model interactions. Reasonable agreement was found between the average derived factors, literature, and WBP and YSOX calculations. Although the coverage of the 3.40 MeV state\u2019s angular distribution is too limited for a definitive parity assignment, it and the spectroscopic analysis tentatively support a positive parity. The implications of this assignment on the rotational structure, 0?3/2 effective single-particle energy, and spin-orbit splitting of the 0? orbitals in 11Be are explored.Description based on online resource. Title from PDF t.p. (Michigan State University Fedora Repository, viewed ).Includes bibliographical references
THE BIOLOGY OF CALICIOPSIS CANKER DISEASES IN NORTH AMERICA
No full textThesis (Ph.D.)--Michigan State University. Plant Pathology - Doctor of Philosophy, 2025Caliciopsis pinea is the causal agent of caliciopsis canker disease. The fungus is an emerging pathogen affecting Pinus strobus (eastern white pine) across its native range in North America. Infections result in canker formation, reduced tree vigor, and economic losses due to downgraded lumber quality. Despite increasing reports of severe disease outbreaks, many aspects of C. pinea\u2019s life cycle, pathogenicity, and mechanisms of spread remain poorly understood. Current diagnostic challenges stem from the pathogen\u2019s morphological similarity to closely related species and its ability to infect hosts without production of visible fruiting structures, necessitating more precise molecular detection methods. This dissertation addresses gaps in the existing literature of this pathosystem by first presenting a comprehensive guide on the diagnostic options available to study the conifer-infecting members of the Caliciopsis genus. Microscopic and molecular tools for diagnosis are reviewed and methods for studying Caliciopsis spp. in the laboratory setting are discussed (Chapter 1). This dissertation also investigates species diversity in the Caliciopsis genus through multigene phylogenetic analyses and the description of new species in Michigan. Microscopic and molecular techniques were combined to create a three-locus concatenated phylogenetic tree using sequences generated in the study and culled from GenBank for an analysis that showed with strong statistical support, the presence of three, previously undescribed Caliciopsis species present in Michigan. These findings are supported by microscopy which demonstrated that morphological differences were present between novel species and other known species of Caliciopsis including length and width of mazaedia, placement of the locule, and ascospore size. Specific epithets are proposed for species described in this study, and a review of the taxonomic history and documentation on the existence of type specimens for all known species of Caliciopsis is offered (Chapter 2). Phylogenetic studies are followed by the development of a highly sensitive and specific quantitative polymerase chain reaction (qPCR) assay targeting the internal transcribed spacer (ITS) region of C. pinea. Several members of the Caliciopsis genus are known pathogens, but C. pinea is the most aggressive on its preferred host. Diagnostic options for this species are limited and are expanded on here with the development of new molecular techniques for detection, quantification, and diagnosis. The assay was validated against 51 target and non-target isolates from across the P. strobus native range, achieving a detection limit of 10 fg of C. pinea DNA. To ensure reproducibility, the assay was tested in multiple laboratories and across different thermocycling platforms. In all cases the reaction detected only C. pinea when screened against non-target species and the target was picked up in the background of plant DNA from infected plant material (Chapter 3). The diagnostic assay developed in these studies was then utilized to investigate the environmental factors influencing C. pinea spore dispersal. To discover optimal conditions for inoculum detection, a novel approach combining qPCR with rotating-arm air sampling was implemented over a six-month sampling period in 2021 and 2022. These air sampling devices were deployed in natural ecosystems to monitor airborne inoculum levels, providing critical insight into spore release patterns. By integrating advanced molecular diagnostics with field-based spore monitoring, this study enhances our ability to detect, diagnose, and understand the epidemiology of C. pinea. The findings have significant implications for forest management, disease mitigation, and the long-term health of eastern white pine (Chapter 4). Cumulatively, this dissertation provides the most comprehensive examination of C. pinea to date, addressing key gaps in its diagnosis, taxonomy, and epidemiology. By integrating phylogenetic analyses, molecular diagnostics, and environmental monitoring, this research enhances our ability to detect, classify, and understand C. pinea and its impact on P. strobus. Understanding spore dispersal dynamics and optimal conditions for inoculum detection provides critical insights for predicting and managing disease outbreaks. Future research should build upon these findings by exploring host-pathogen interactions at the molecular level, assessing environmental factors driving disease progression, and expanding monitoring efforts across different regions and climate conditions. As forest ecosystems face increasing stress from climate change, invasive species, and emerging pathogens, proactive disease management is essential for maintaining forest populations and overall resilience. This dissertation contributes valuable tools and foundational knowledge toward that goal, providing a framework for future studies and informing strategies to mitigate the impact of caliciopsis canker disease on North American forests.Description based on online resource. Title from PDF t.p. (Michigan State University Fedora Repository, viewed ).Includes bibliographical references
EXAMINING THE ROLE OF WORK DOMAINS AND JOB STRAIN ON PRETERM BIRTH AMONG BLACK MOTHERS
Full text linkThesis (Ph.D.)--Michigan State University. Epidemiology - Doctor of Philosophy, 2025ABSTRACTBackground and Objectives: Preterm birth (PTB) contributes substantially to neonatal mortality, morbidity, and long-term neurological disabilities. While many potential risk factors for PTB have been extensively studied, workplace exposures and experiences during pregnancy have rarely been studied, especially among Black women. My dissertation aimed to 1) evaluate the associations between multiple dimensional work exposures (work hours, physical demands, psychological demands, job strain) and PTB, 2) determine if psychosocial factors (social support, depressive symptoms, stress) and lifetime experiences of racism moderate the associations. Methods: Using cohort data of Black women residing in Baltimore, we conducted a within-group analysis restricted to the 429 women employed during pregnancy. We used log-binomial regression analyses to determine the role of work exposures on PTB risk and to adjust for the potential covariates. We conducted moderation analyses on a multiplicative scale by adding an interaction term between the work exposure and the potential moderator to the adjusted regression models. We determined the significance of the interaction terms using the Likelihood Ratio (LR) chi-square test and a p-value less than 0.10. Results: Positive associations between PTB and prolonged working hours (aPR = 1.56; 95% CI: 0.75, 3.24), lifting heavy loads (aPR = 1.33; 95% CI: 0.88, 2.00). Working with physically awkward body positions was associated with lower PTB rates (aPR = 0.67; 95% CI: 0.43,1.07). Highest psychologically demanding work (top quartile vs. lower three quartiles) was significantly associated with PTB (aPR = 1.82; 95% CI: 1.20, 2.76). Modest PTB associations were observed with jobs that required an excessive amount of work (aPR=1.32; 95% CI: 0.84,2.07) or not having enough time to complete work (aPR=1.49; 95% CI: 0.92,2.42). We observed modest associations with PTB for women with high strain (aPR=1.47; 95% CI: 0.80,2.72), active (aPR=1.42; 95% CI: 0.76,2.66), and intermediate strain jobs (aPR=1.36; 95% CI: 0.81,2.27). Women enrolled postpartum had elevated PTB rates when working longer hours (aPR= 2.65; 95%CI: 1.00,7.01). Evidence of moderation by psychosocial factors for the PTB work exposure associations. High physically demanding work was associated with high PTB rates among women with low social support (aPR:1.90; 95% CI: 0.94,3.85). High psychologically demanding work was significantly associated with increased PTB rates among women with low social support (aPR: 1.92; 95% CI: 1.16, 3.17) and high depressive symptoms (aPR: 1.99; 95% CI: 1.12, 3.52). Among women with low social support, active (aPR: 2.47; 95% CI:1.12,5.44), high strain jobs (aPR: 2.05; 95% CI:0.93,4.53) were associated with increased PTB rates. Among women with high depressive symptoms, active (aPR: 3.10; 95% CI:1.07,8.98) and high strain jobs (aPR: 3.59; 95% CI:1.28,10.05) and passive jobs (aPR: 2.32; 95% CI:0.78,6.89) were associated with increased PTB rates. Conclusion: Physically demanding work activities may increase PTB rates in Black women, with evidence of interactions with social support. Black women with psychologically demanding work activities are at elevated risk of PTB, with evidence of interactions with psychosocial factors. PTB rates were elevated for women with active and high strain jobs after considering psychosocial factors. Evidence of interactions between the work exposures and psychosocial factors suggests that impacts are intertwined. Findings underscore the importance of implementing policies and measures that foster a supportive work environment for pregnant women to ensure better pregnancy outcomes.Description based on online resource. Title from PDF t.p. (Michigan State University Fedora Repository, viewed ).Includes bibliographical references
Hierarchical models for small area estimation using zero-inflated forest inventory variables : comparison and implementation
Full text linkThesis (M.S.)--Michigan State University. Statistics - Master of Science, 2025National Forest Inventory (NFI) data are typically limited to sparse networks of sample locations due to cost constraints. While traditional design-based estimators provide reliable forest parameter estimates for large areas, there is increasing interest in model-based small area estimation (SAE) methods to improve precision for smaller spatial, temporal, or biophysical domains. SAE methods can be broadly categorized into area- and unit-level models, with unit-level models offering greater flexibility---making them the focus of this study. Ensuring valid inference requires satisfying model distributional assumptions, which is particularly challenging for NFI variables that exhibit positive support and zero inflation, such as forest biomass, carbon, and volume. Here, we evaluate a class of two-stage unit-level hierarchical Bayesian models for estimating forest biomass at the county-level in Washington and Nevada, United States. We compare these models to simpler Bayesian single-stage and two-stage frequentist approaches. To assess estimator performance, we employ simulated populations and cross-validation techniques. Results indicate that small area estimators that incorporate a two-stage approach to account for zero inflation, county-specific random intercepts and residual variances, and spatial random effects provide the most reliable county-level estimates. Additionally, findings suggest that unit-level cross-validation within the training dataset is as effective as area-level validation using simulated populations for model selection. We also illustrate the usefulness of simulated populations for better assessing qualities of the various estimators considered.Description based on online resource. Title from PDF t.p. (Michigan State University Fedora Repository, viewed ).Includes bibliographical references
DEGRADATION OF POLYMERIC ADHESIVES IN ADVERSE ENVIRONMENTAL CONDITIONS
Full text linkThesis (Ph.D.)--Michigan State University. Civil Engineering - Doctor of Philosophy, 2025Cross-linked elastomers, known for their exceptional flexibility, toughness, formability, and versatility, play a vital role in a wide array of engineering applications across aerospace, construction, transportation, marine, aeronautics, and automotive sectors. These materials are expected to maintain high performance throughout their service life, even when exposed to aggressive environmental conditions such as water infusion, temperature fluctuations, and ultraviolet (UV) radiation. These environmental factors pose significant challenges, as they can gradually deteriorate the material\u2019s properties and reduce its overall durability.Among the most critical forms of environmental degradation are thermal aging under oxygen-deficient conditions and oxidative aging caused by elevated oxygen concentrations. The former typically results in uniform thermal degradation of the material, while the latter, known as diffusion-limited oxidation (DLO), induces spatially heterogeneous damage, primarily at the surfaces of the polymer where oxygen diffusion is more pronounced. Together, these two forms of aging represent fundamentally inverse degradation conditions\u2014one being inert and volumetric, and the other being oxidative and surface-driven. Accurate prediction of the long-term behavior of elastomers under both these conditions is essential for designing reliable rubber components that resist early failure in service.To address this need, high-fidelity constitutive models are essential for simulating the effects of aging on the mechanical, thermal, and failure characteristics of cross-linked polymers. Historically, most aging models have employed hyperelastic constitutive laws coupled with single-kinetic degradation equations to model the evolution of material properties over time. While these approaches have been useful in capturing basic degradation trends, they often fall short in representing the complex interactions between microstructural evolution and macroscale mechanical behavior under realistic service conditions.This dissertation presents a comprehensive multi-physics modeling framework to capture the distinct and coupled degradation behaviors of cross-linked polymers under both diffusion-limited oxidation and inert thermal aging. These models incorporate the effects of oxygen diffusion, reaction kinetics, and thermally activated chain scission and cross-linking processes to simulate the evolution of polymer microstructure over time. By resolving the spatial and temporal development of aging parameters, the framework successfully reproduces both uniform and spatially heterogeneous degradation phenomena, providing critical insight into how these opposing environmental factors influence long-term material performance.The modeling approach is grounded in continuum mechanics and integrates finite strain theory with micro-mechanically motivated degradation mechanisms. Rubber elasticity is described across three scales: statistical mechanics at the microscale to account for molecular chain behavior, network-based phenomenological modeling at the mesoscale, and continuum theory at the macroscale. This multi-scale approach enables the representation of polymer network reconfiguration during aging, which is essential for predicting stiffness loss, permanent deformation, and eventual failure.While the core of this dissertation focuses on physics-based modeling of aging mechanisms, recent advancements in machine learning (ML), particularly physics-informed neural networks (PINNs), offer promising opportunities to enhance traditional modeling techniques. Although early generations of data-driven black-box models were limited by their need for large datasets and lack of physical constraints, hybrid approaches\u2014where experimental macroscopic data are used to infer underlying microstructural behavior within physics-informed frameworks\u2014have begun to bridge this gap. In this work, such techniques are explored in a supporting capacity to augment the predictive capabilities of the proposed aging models, without compromising the underlying physical consistency.By coupling the two degradation models and incorporating both mechanistic understanding and data-driven insights, this dissertation delivers a unified computational framework capable of simulating the long-term behavior of elastomeric materials under varied environmental exposures. The results not only enhance our understanding of how oxidative and inert aging conditions uniquely and jointly affect polymer durability, but also provide a practical foundation for the design of next-generation elastomers with improved resistance to environmental degradation.Description based on online resource. Title from PDF t.p. (Michigan State University Fedora Repository, viewed ).Includes bibliographical references
Disrupting Monospectral Multilingualism : A Participatory Design Research Study to Cultivate Critical Multilingual Awareness in Spanish World Language Teacher Preparation
No full textThesis (Ph.D.)--Michigan State University. Curriculum, Instruction, and Teacher Education - Doctor of Philosophy, 2025This dissertation investigates how Spanish pre-service teachers (PSTs) develop Critical Multilingual Awareness (CMLA) in a World Language (WL) teacher preparation program, focusing on their evolving understandings of multilingualism, pedagogy, and classroom practice. Grounded in CMLA and participatory design research, the study followed two PSTs across two semesters of coursework and practicum, examining how iterative co-design, reflection, and relational inquiry shaped their language ideologies and teaching approaches.Drawing on data from discussions, observations, reflections, interviews, and 22 co-designed activities, the study addresses three research questions. First, it reveals how PSTs initially adopted monospectral multilingualism\u2014a stance that nominally embraced diversity but reinforced standardized, depoliticized norms. Second, it shows how design-based inquiry supported ideological and pedagogical shifts toward broader representations of language and identity. Third, these shifts informed inclusive practices, affirming multilingual learners\u2019 home languages, and expanding cultural content in elementary Spanish instruction.Theoretically, the study conceptualizes monospectral multilingualism as a pervasive stance in WL education and advances CMLA as an enactable orientation. Methodologically, it positions participatory design research as both inquiry and pedagogy, highlighting PSTs\u2019 sense-making through collaborative, justice-oriented design. Practically, it brings greater visibility to multilingual learners from language backgrounds beyond English and Spanish, positioning early WL instruction as a critical space for equity-driven pedagogical innovation. The study offers a model for reimagining teacher preparation as a space for ideological unlearning, pedagogical agency, and relational transformation.Description based on online resource. Title from PDF t.p. (Michigan State University Fedora Repository, viewed ).Includes bibliographical references
Powering the Infrastructure for Critical Services : Ensuring Secure and Reliable Emergency Communications over Cellular Networks
Full text linkThesis (Ph.D.)--Michigan State University. Computer Science - Doctor of Philosophy, 2025Cellular networks (4G, 5G, and beyond), the only large-scale wireless network infrastructure on par with the Internet, play an indispensable role in supporting not only daily voice, text, and data services but also critical services such as emergency services. Emergency communication over cellular networks is a vital part of our nation\u2019s emergency response and disaster preparedness system. To maximize emergency service availability, there are some special requirements from standard organizations and administrative authorities. For example, in the U.S., the Federal Communications Commission (FCC) stipulates that cellular carriers must transmit all wireless 911 calls without call validation to Public Safety Answering Points (PSAPs). The 3GPP standard provides emergency services with higher priority than non-emergency services and enables them across all available radio access technologies, generations, and operators. Therefore, ideally, by design, users are supposed to access emergency services anytime and anywhere, as long as wireless coverage is available.However, it is very challenging to support such emergency communications. An operational cellular infrastructure usually comprises multiple generations of cellular networks, such as 5G Standalone, 5G Non-Standalone, 4G, and 3G, using different radio access technologies, including 5G NR (New Radio), 4G E-UTRA (Evolved Universal Terrestrial Radio Access), or even public/private Wi-Fi networks. However, the security mechanisms and supported services of different generations are not equally reliable. Moreover, to maximize emergency service support, networks must permit some insecure operations, such as allowing anonymous emergency access for roaming users or users without mobile subscriptions. These special operations, while essential, similar to backdoors, introducing potential attack surfaces. Even more threatening, emergency and non-emergency services share the same underlying infrastructure. Therefore, any design flaw in emergency services can compromise the security and reliability of the entire mobile ecosystem. Despite their importance, emergency services remain underexplored, as prior work mainly targets user equipment or simulated DoS attacks, lacking systematic study of such critical infrastructure.This dissertation presents our research on powering the infrastructure for critical services to ensure secure and reliable emergency communications over cellular networks. We highlight our research insights and findings on: (1) identifying design defects in cellular emergency service standards, and (2) investigating the security and reliability of operational emergency services in the U.S. and other countries/areas, along with the technical challenges we encountered and our approaches to addressing them. Our results show that, from a security perspective, operational cellular emergency services are not only abusable but also deniable. For example, an adversary can block a victim's emergency calls by sending just a single message to the carrier network. Adversaries without purchasing any mobile subscription can obtain free data, voice, and text services through the high-priority emergency communication channel. Even more threatening, our study also reveals that, in some situations, with sufficient wireless coverage, emergency calls cannot be made within 2 minutes, whereas non-emergency calls at the same locations can be made within 3-6 seconds. Finally, we conclude our existing research on studying critical emergency services, discuss new challenges and opportunities for safeguarding next-generation emergency services, and outline future research directions.Description based on online resource. Title from PDF t.p. (Michigan State University Fedora Repository, viewed ).Includes bibliographical references
BECOMING THE BRIDGE : AN ETHNOGRAPHIC-CASE STUDY OF TEACHER IDENTITY, IDEOLOGY, AND CRITICAL CONSCIOUSNESS IN A DUAL LANGUAGE BILINGUAL EDUCATION PROGRAM
No full textThesis (Ph.D.)--Michigan State University. Second Language Studies - Doctor of Philosophy, 2025This ethnographic case study examines the identity constructions and critical consciousness praxis of a Multiracial, Chinese American heritage speaker teaching in a Mandarin dual language bilingual education (DLBE) program. Drawing on a range of ethnographic data collected over one academic year, the study explores how this teacher navigates and challenges dominant language ideologies within a school that houses a Mandarin DLBE strand program. Adopting a chronotopic approach, the analysis highlights how circulating ideologies\u2014specifically monoglossia and transglossia\u2014shape the types of identities that can be performed and recognized within different spacetimes of the school. I argue that while monglossic ideologies tend to restrict identity possibilities to static categories, transglossic ideologies allow for more expansive and authentic identity positionings, and show how the focal participant actively draws on his lived experiences and identities privileged by dominant ideologies to introduce and sustain chronotopes of transglossia\u2014thereby creating space for affirming minoritized identities and fostering a stronger sense of belonging and community for both students and teachers.Description based on online resource. Title from PDF t.p. (Michigan State University Fedora Repository, viewed ).Includes bibliographical references
The clinical nurse specialist in the community hospital : impact on hospital-acquired pressure injuries
No full textProblem: Hospital-acquired pressure injuries (HAPIs) are a significant challenge, leading to adverse outcomes such as pain, infections, and prolonged hospital stays. Clinical Nurse Specialists (CNS) play a key role in preventing these injuries by promoting and carrying out evidence-based practices. Purpose: This project aims to reduce HAPIs in a Midwest community hospital by leveraging CNS-led interventions to improve patient care. Methods: Evaluating the outcomes of HAPIs in the community hospital setting included pre- and post-surveys of bedside nurse confidence in HAPI prevention strategies, a prevalence survey inclusive of a skin audit, and data outcomes analysis pre- and post-implementation. Results: The project aimed to reduce the incidence of HAPIs by at least 10% and increase the confidence of bedside nurses in the prevention/reduction of HAPIs. Prior to interventions, the HAPI rate was 1.76 per 1,000 patient days. Post-intervention, the rate was lowered to 1.62 per 1,000 patient days. Conclusion: A CNS can implement and support HAPI prevention measures in the community hospital setting, reducing and preventing HAPI incidence. Keywords: Hospital Acquired Pressure Injury (HAPI), Clinical Nurse Specialist (CNS)Thesis (D.N.P.)--Michigan State University. Clinical nurse specialist, 2025Includes bibliographical references (pages 27-30
Defining urgent vs. non-urgent messaging in primary care to standardize workflow : a DNP project
No full textProblem: There is a lack of communication concerning the purpose, use, and boundaries of urgent vs. non-urgent messaging between call center staff, triage nurses, and providers. This is leading to mislabeling of such messaging and causing subsequent stress and frustration for triage nurses and providers. Purpose: The purpose of this doctoral project is to improve the process of urgent vs. non-urgent messaging using EHR templates (i.e., text macros) and corresponding algorithms as demonstrated by increased staff satisfaction. Methods: Key stakeholder interviews and a thorough literature review were completed to determine interventions. 10 common patient inquiries were identified; five urgent and five non- urgent. Corresponding text macros and algorithms were created to assist with decision making and documentation. To educate staff on implementation, instructional sessions were performed, and visual aids of the text macros and algorithms were provided. Research revealed that EHR templates (i.e., text macros) increase patient safety, documentation quality, workplace efficiency, and staff satisfaction. Pre-, intra-, and post-intervention surveys were completed to assess these themes. The PDSA QI Model was utilized and adhered to throughout this project. Results: The pre-, intra-, and post-intervention survey results demonstrated a positive trend in staff satisfaction regarding the electronic messaging process after implementing the EHR templates and algorithms, supporting the four themes identified in the literature (i.e., patient safety, documentation quality, workplace efficiency, and staff satisfaction). Conclusions: EHR templates (i.e., text macros) and corresponding algorithms can be used to increase documentation quality, workplace efficiency, and staff satisfaction. This ultimately improves patient safety. Clinical recommendations include using this project as a guide to standardize workflow in urgent vs. non-urgent messaging.Thesis (D.N.P.)--Michigan State University. Family nurse practitioner, 2025Includes bibliographical references (pages 30-33