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RECIPROCAL INTERACTIONS BETWEEN TAU AND MICROGLIAL SENESCENCE DURING THE DEVELOPMENT OF ALZHEIMER-LIKE PATHOLOGY IN MOUSE MODELS
Full text linkThesis (M.S.)--Michigan State University. Neuroscience - Master of Science, 2025This review explores Alzheimer's Disease (AD) and Frontotemporal Dementia (FTD) focusing on the complex pathophysiology, advanced diagnostic methodologies, and emerging therapeutic strategies. It synthesizes a wide array of studies to elucidate the molecular, cellular, and systemic changes characteristic of these disorders. Additionally, the review examines the socio-economic impacts and caregiver burden associated with these diseases, highlighting the need for innovative approaches in treatment and care. The effect of cellular senescence on the progression of disease pathology and symptomology; markers and mechanisms of senescence are identified and explored in this review. The document aims to provide an in-depth analysis, identify gaps in current knowledge, and propose directions for future research.Description based on online resource. Title from PDF t.p. (Michigan State University Fedora Repository, viewed ).Includes bibliographical references
PHYSIOLOGICAL MECHANISMS AND MANAGEMENT STRATEGIES ASSOCIATED WITH ANNUAL BLUEGRASS RESISTANCE TO ICE ENCASEMENT STRESS
Full text linkThesis (M.S.)--Michigan State University. Crop and Soil Sciences - Master of Science, 2025Annual bluegrass (Poa annua) is a cool-season, managed turfgrass species that is susceptible to winter injury, particularly ice encasement. Development of winter preparatory practices in the fall is important for turfgrass managers to decrease the incidence and costs associated with ice encasement damage. In the first experiment, a two-year growth chamber study evaluated the effect of fall soil water content (SWC) at three different levels (8%, 12%, and 20%) on ice encasement survival. Plants were analyzed for relative water content, percent recovery, total nonstructural carbohydrates, and lipid peroxidation. Low SWC during cold acclimation improved recovery could be associated with higher root TNC content. In the second experiment, plant growth regulator (PGR) treatments in the fall season were used to evaluate their ice encasement recovery in controlled conditions and field spring recovery. Field plots were treated with mineral oil, aminoethoxyvinylglycine (AVG), ethephon [(2-chloroethyl)phosphonic acid)], and a control (water). Refraining from high levels of ethephon or reducing water inputs during the fall acclimation period may reduce annual bluegrass stand loss due to ice encasement. A third growth chamber experiment was conducted to observe the differences in gas accumulation between creeping bentgrass (Agrostis stolonifera; ice encasement tolerant) and annual bluegrass (ice encasement sensitive) during ice encasement and after melt. Annual bluegrass had reduced regrowth after ice encasement when compared to creeping bentgrass, which could be associated with higher amounts of ethylene and CO2 in annual bluegrass plants and a decrease in glucose and fructose after 20 d of ice encasement. This research improves our understanding of the effects of ice encasement on turfgrass growth, winterkill preventative management practices, and mechanisms that may correlate to ice encasement resilience.Description based on online resource. Title from PDF t.p. (Michigan State University Fedora Repository, viewed ).Includes bibliographical references
DETERMINING THE ESTABLISHMENT POTENTIAL OF GANASPIS KIMORUM IN MICHIGAN
Full text linkThesis (M.S.)--Michigan State University. Entomology - Master of Science, 2025Drosophila suzukii is an invasive pest that has disrupted existing IPM strategies of cherry and small fruit industries. Shortly after its introduction, D. suzukii established across the United States, by exploiting non-crop habitats and infesting thin-skinned fruit monocultures. Using its serrated ovipositor, females can infest wild and cultivated fruit throughout the growing season. In Michigan, native predators are insufficient for suppressing D. suzukii populations, creating a dependency on chemical sprays. However, populations residing in wild refugia adjacent to agricultural fields are left untreated and require alternative methods. Drosophila suzukii natural enemies within its native range were investigated, in search for a classical biocontrol agent. Ganaspis kimorum (formerly G. brasiliensis) was found to be an exclusive larval parasitoid of D. suzukii and a potential self-regulating method of targeting pest populations. I investigated the ability of G. kimorum to overwinter in Michigan fields, near locations of release and the abiotic factors that influence its success. Snow cover and number of days where wasps were exposed to ground temperatures below freezing influenced survival. I also evaluated G. kimorum dispersal capability and host finding behavior using baited traps just after harvest; however, no G. kimorum was detected in sentinel traps. Specimens of this species were found in fruit surveys conducted at release sites, along with adventive populations of Leptopilina japonica. This is the first detection of G. kimorum emerging from established D. suzukii in Michigan agricultural fields. These findings will be influential in determining the future success of establishing G. kimorum as a biocontrol agent against D. suzukii populations.Description based on online resource. Title from PDF t.p. (Michigan State University Fedora Repository, viewed ).Includes bibliographical references
Fairness and Accessibility in Multimodal AI Recruitment : Assessing and Mitigating Bias Across Text, Video, and Speech
No full textThesis (Ph.D.)--Michigan State University. Electrical and Computer Engineering - Doctor of Philosophy, 2025Artificial intelligence (AI) is rapidly reshaping how people work, with up to 30% of work activities projected to be automatable by 2030. As of 2024, 42% of enterprise organizations have adopted AI in their operations, and half of surveyed companies now incorporate AI into their hiring processes\u2014a figure projected to rise to 68% within the next year. These systems are now used to automate resume screening, conduct chatbot-based interviews, and evaluate candidate personality traits and skills through video analysis. While they offer efficiency and scalability, their growing role in high-stakes employment decisions has raised serious concerns about fairness, transparency, and accessibility. In particular, AI-driven recruitment systems have demonstrated tendencies to reinforce gender biases and disadvantage individuals with speech disfluencies, such as stuttering. This dissertation addresses these challenges by examining the fairness and effectiveness of AI systems across three key modalities\u2014text, video, and speech\u2014and proposes novel strategies to mitigate bias across all three.Specifically, it makes three core contributions spanning adaptive assessments, automated video interview scoring, and accessibility in speech-based technologies:First, we develop a multi-objective optimization framework for computerized adaptive testing that balances precision, test length, content coverage, item exposure, and fairness. By integrating evolutionary algorithms and large language models, our approach reduces assessment time without sacrificing accuracy, while also examining fairness trade-offs related to item exposure, memorization, and shortened assessments.Second, we introduce a multimodal, multi-task deep neural network that predicts OCEAN personality traits from video interviews more efficiently than existing models. To measure and mitigate bias, we implement a counterfactual fairness framework using generative adversarial networks, enabling us to evaluate how changes to protected attributes (e.g., gender, age) affect model predictions. This ensures fairer treatment across demographic groups in personality-based scoring systems.Third, we conduct a first-of-its-kind analysis of bias in automatic speech recognition (ASR) systems against individuals who stutter\u2014a group historically underserved and disadvantaged by voice-based technologies. Using both synthetic and real-world data, we identify significant accuracy disparities in commercial and open-source ASRs. To address these, we propose a two-stage bias mitigation strategy: (1) fine-tuning pre-trained ASRs with disfluency-augmented data using parameter-efficient methods, and (2) correcting ASR transcript errors using large language models with retrieval-augmented generation. To support this work, we developed a novel cloud-based data collection platform to build one of the largest datasets of stuttered speech to date, collected across diverse speakers and application contexts.Overall, this dissertation provides a comprehensive roadmap for improving fairness, accessibility, and efficiency in AI-based recruitment, offering actionable strategies for organizations aiming to build fair, inclusive, and effective hiring pipelines in an increasingly AI-driven world.Description based on online resource. Title from PDF t.p. (Michigan State University Fedora Repository, viewed ).Includes bibliographical references
NOVEL STRATEGIES IN BROMOPYRROLE ALKALOID SYNTHESIS WITH EMPHASIS ON PYRROLOPIPERAZINONE SCAFFOLD : APPLICATION TO TOTAL SYNTHESIS OF ASPIDOSTOMIDES D, E AND F AND ASPIDAZIDE A
No full textThesis (Ph.D.)--Michigan State University. Chemistry - Doctor of Philosophy, 2025Natural products with complex molecular architectures often serve as valuable leads for therapeutic agents. This thesis focuses on the synthesis and characterization of biologically significant natural products, with an emphasis on the pyrrolopiperazinone scaffold\u2014a structural motif frequently found in bioactive compounds. Chapter 1 provides a comprehensive review of the pyrrolopiperazinone scaffold, highlighting its occurrence in natural products, synthetic methodologies, and biological significance. This foundational overview informs the subsequent research efforts. Chapter 2 describes efforts toward the synthesis of Aspidazide A, a natural product with a distinct framework. Although the total synthesis was not completed, significant progress was made, including the successful construction of the phenyl pyrrolopiperazinone scaffold in six steps with an overall yield of 11%. Efforts toward electrochemical N-N oxidative coupling are also discussed. Chapter 3 focuses on the efforts toward the total syntheses of Aspidostomides D, E, and F, showcasing the successful construction of the indole pyrrolopiperazinone scaffold in eight steps with a 49% yield. Progress was made in late-stage bromination and \u3b1-methoxylation, addressing challenges in regioselectivity and functional group compatibility to produce advanced intermediates. Future directions highlight the potential to further decorate phenyl and indole pyrrolopiperazinone scaffolds via regioselective bromination or enantioselective \u3b1-methoxylation, enabling the synthesis of novel analogues. These derivatives offer promising opportunities for exploration in medicinal chemistry, paving the way for the discovery of new therapeutic agents.Description based on online resource. Title from PDF t.p. (Michigan State University Fedora Repository, viewed ).Includes bibliographical references
THERMAL AND ELASTIC PROPERTIES OF INTERMETALLIC ZINTL COMPOUNDS : INFLUENCE OF COVALENT NETWORK DIMENSIONALITY
No full textThesis (Ph.D.)--Michigan State University. Materials Science and Engineering - Doctor of Philosophy, 2025The crystal structure and bonding characteristics of intermetallic compounds critically influence their thermal and elastic properties. Polymorphic phase transitions \u2013 where crystal structures transform without altering atomic composition \u2013 offer a unique window to directly probe the relationship between atomic arrangement and thermal properties. Intermetallic Zintl compounds provide an intriguing case study, as they exhibit both ionic and covalent bonding frameworks within a single crystal lattice. Within the AMX Zintl family (where A = alkali-metal or alkaline earth metal, M = transition metal, X = non-metal), a series of closely related crystal structures feature a covalent sublattice that transitions progressively from a two-dimensional (2D), graphene-like configuration to a fully interconnected three-dimensional (3D) network. By examining these crystallographic transitions, we uncovered concrete correlations between the dimensionality of covalent bonding and the resulting thermal properties. We first explored the changes in thermal transport properties in the compound YbCuBi, as its crystal structure transitions from a flat 2D covalent sublattice (Space group \u2013 P63/mmc) to a buckled quasi-2D covalent network (Space group \u2013 P63mc) with periodic interlayer interactions. Using a combination of resonance ultrasound spectroscopy, inelastic neutron scattering, and first-principles calculations, we studied the impacts of this crystallographic transition on acoustic and optical phonons. Thermal conductivity measurements elucidated how changes in phonon energies and elastic behavior impact the thermal transport characteristics. Building on this, we also investigated a quasi-2D to 3D covalent phase transition in the CaAgSb1-xBix solid solution. Isoelectronic substitution of Sb by Bi systematically alters the elastic properties, while the crystallographic transition induces a \u2018step-like\u2019 change. Lattice parameters from x-ray diffraction reveal the underlying mechanism of the phase transition, while resonance ultrasound spectroscopy elucidates its impact on elastic properties. We also explore the limitations of Weidemann-Franz approximation for heat transport by charge carriers, highlighting the boundaries in our current understanding of thermal transport by quasiparticles. In the process, we discover promising thermoelectric properties in CaAgSb, attributed to its low thermal conductivity and high electronic mobility. According to the single parabolic band model, reducing carrier concentration could potentially enhance the thermoelectric performance of CaAgSb. Therefore, we conduct a \u2018phase-boundary mapping\u2019 study, combining first-principles density functional theory calculations and experiments to elucidate the behavior of carrier-generating defects under different growth conditions. We identify Ag vacancies as the defects with the lowest formation energy under all growth conditions, limiting Fermi level tuning to a narrow window, and suggesting that other routes may be needed to optimize the thermoelectric efficiency of CaAgSb.Description based on online resource. Title from PDF t.p. (Michigan State University Fedora Repository, viewed ).Includes bibliographical references
STORYING ABROAD : NARRATIVES OF EDUCATION ABROAD BY FORMER STUDENTS OF LOWER-SOCIOECONOMIC STATUS
Full text linkThesis (Ph.D.)--Michigan State University. Higher, Adult, and Lifelong Education - Doctor of Philosophy, 2025In the United States, education abroad is popularly perceived as an opportunity reserved for privileged students, to have a fun vacation inspired by the idea of the European Grand Tour or enhance their employability through distinctive experiences that increase their status and qualifications in a globalizing labor market. In either of these cultural narratives, students are anticipated to both possess and acquire significant capital through the study abroad experience and deploy it upon their return. Despite these expectations, not all study abroad students come from privileged backgrounds, especially as participation has become more accessible over the last several decades. This study used a qualitative, narrative-inspired approach, informed by a theoretical lens of capital, to explore the ways former students of lower-socioeconomic status backgrounds remember and represent their study abroad experiences after a significant amount of time has passed and how their narratives intersect with pre-existing cultural narratives of education abroad. I conducted a series of two narrative-inspired interviews with eight students who studied abroad in the early 21st century. The findings of this study show that themes of Investing, Exploring, and Becoming are present in the ways these individuals remember and represent their education abroad experiences. Further, their narratives both reflect and nuance existing cultural narratives about study abroad.Description based on online resource. Title from PDF t.p. (Michigan State University Fedora Repository, viewed ).Includes bibliographical references
MASS TIMBER CURRICULUM IN THE U.S. IN ENGINEERING, ARCHITECTURE, AND CONSTRUCTION DISCIPLINES : CURRENT STATE OF ADOPTION, GAPS, AND NEEDS ANALYSIS
Full text linkThesis (M.S.)--Michigan State University. Civil Engineering - Master of Science, 2025Mass timber is a sustainable construction material that is increasing in demand throughout the engineering, architecture, and construction (AEC) fields in the United States. While it is gaining popularity, there are several barriers that still exist in the adoption of mass timber in the AEC industry. One of these barriers is the lack of mass timber curricula and educational resources in accredited programs across undergraduate and graduate institutions in the U.S. By analyzing information gathered from syllabi and interviews of instructors teaching classes with timber and mass timber components in accredited programs, this study aims to establish the current state of integration of timber and mass timber related content in engineering, architecture, and construction curricula and how they compare to one another. Results suggest that there is currently a relatively low number of timber and mass timber courses available in accredited higher educational institutions across the AEC fields, with architecture having the largest number and construction having the smallest. Engineering offers the largest number of mass timber-specific courses, while construction has the least. Within AEC classes, the curriculum content also predominantly focuses on the structural and design applications of mass timber. This highlights the opportunity for more comprehensive coverage of technology, construction, and materials concepts across all three disciplines. A lack of available instructional tools was also prominently discussed, with many instructors citing a lack of formal instructional materials, real-world examples, and case studies. It was also found that instructors with industry experience had an easier time creating and/or identifying these materials, suggesting that courses with industry experience-led instructors tend to currently provide a greater amount of mass timber educational content in comparison to courses without. Lastly, the instructor-suggested resources and solutions identified that could most help further support the increased adoption of mass timber curriculum included case studies and design projects, and instructional materials that include problem sets and lecture notes.Description based on online resource. Title from PDF t.p. (Michigan State University Fedora Repository, viewed ).Includes bibliographical references
COMPACTION EFFECT ON DIFFERENT DENSITIES OF CANCELLOUS BONE AND IMMEDIATE STABILITY OF AN ANGLE STABLE INTERLOCKING NAIL IN A DISTAL FEMORAL OSTEOTOMY MODEL
Full text linkThesis (M.S.)--Michigan State University. Comparative Medicine and Integrative Biology - Master of Science, 2025Background: Interlocking nails are becoming a common alternative to plates used to stabilize the femur following corrective surgery for medial patellar luxation. Intraoperative manipulation of the femoral condyle can lead to loss of initial nail stability, increasing the risk of malalignment. The use of cancellous bone compaction, as opposed to traditional reaming, has the potential to improve the mechanical properties of the nail-bone construct. Objectives: To evaluate the effect of compaction on the microstructure and mechanical properties of the bone/nail interface in a simulated femoral condylar bone model. Methods: Foam models of different densities (7.5, 10, 12.5, 15, and 20 PCF, n=5/group) were prepared using either standard line-to-line reaming (7 mm) or sequential compaction using custom mandrels of increasing diameters from 4 mm to 7 mm. Five samples from each group were tested in mediolateral bending. Impaction stiffness was assessed for each mandrel size and I-Loc nail in compacted foams (n=4/group). Three specimens per group were evaluated by micro-computed tomography (micro-CT) to define the effects of compaction on foam microstructure. Results: Compaction increased both construct bending stiffness, as well as load at 5 mm displacement across all tested foam densities (p<0.0001). Impaction test showed increasing stiffness and load at 32 mm from 4 mm mandrel to 7 mm mandrel, with the I-Loc nail performing similarly to the 6 mm mandrel. Micro-CT scan results demonstrated that higher density foams (10 PCF and above) exhibited more pronounced differences between drilled and compacted samples. Compaction effects on microstructure were quantified, showing increased local density and altered pore morphology in compacted regions. Conclusion: Compared to conventional reaming, cancellous bone compaction significantly increases the immediate stability of the bone/nail interface in a distal femoral osteotomy model.Description based on online resource. Title from PDF t.p. (Michigan State University Fedora Repository, viewed ).Includes bibliographical references