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Implicit Feature-Based Suppression is Effective at Guiding Attention, even with Strong Target Guidance, while Explicit Feature-Based Suppression is Ineffective
Get PDFThesis (Ph.D.)--Michigan State University. Psychology - Doctor of Philosophy, 2025Evidence for feature-based suppression (FBS) in visual search literature has been controversial and mixed. Much of the mixed findings are due to differences between implicit FBS, the unconscious ignoring of a feature that appears as a distractor with high regularity, and explicit FBS, the active biasing of attention away from a feature. Given this discrepancy, the goal of this dissertation is to examine the benefits of implicit and explicit FBS in a visual search task. Across four experiments, participants searched for a Landolt C with a horizontal gap among eight distractors with vertical gaps, with three items appearing in each of three colors. In Experiment 1, one color (ignored color) appeared on a higher percentage of trials (80%) and always appear as a distractor. Participants were not explicitly aware of the suppression contingency with the goal that they would implicitly learn to ignore this color. In Experiment 2, we included an additional implicit feature-based gain (FBG) contingency - a color (attend color) appeared on a large percentage of trials (40%) and always as the target - to see if suppression of the ignore color persists if there is an implicit feature-based gain (FBG) component present. Experiment 3 replicated Experiment 2 but made the FBG component explicit by cuing participants about the color that was likely to be the target. Experiment 4 replicated Experiment 1 but made the FBS component explicit by cuing what color should be ignored. Experiment 1 found a strong implicit suppression benefit that required minimal training of the to-be-ignored feature. However, in Experiment 2 where there were implicit FBS and FBG contingencies, only the FBG impacted search \u2013 suggesting that implicit FBG interfered with the development or implantation of an implicit FBS mechanism. However, when the FBG component was made explicit (Exp. 3), the implicit FBS effect reappeared \u2013 suggesting the failure to find FBS in Experiment 2 was likely due to a competition for implicit resources between the FBG and FBS components. Finally, when FBS appeared alone but was made explicit (Experiment 4) there was week evidence for suppression. These findings suggest that implicit FBS can effectively allocate attention, but the circumstance under which they do so are limited \u2013 only when the contingencies are learned implicitly and in the absence of implicit feature-based gain contingencies. These restrictions may limit FBS\u2019s utility as a real-world mechanism for guiding attention.Description based on online resource. Title from PDF t.p. (Michigan State University Fedora Repository, viewed ).Includes bibliographical references
ROLE OF PROSTAGLANDINS IN ENDOMETRIAL RECEPTIVITY AND PREGNANCY SUCCESS IN THE MURINE MODEL
Get PDFThesis (Ph.D.)--Michigan State University. Cell and Molecular Biology - Doctor of Philosophy, 2025Non-steroidal anti-inflammatory drugs (NSAIDs) that inhibit prostaglandin synthase (PTGS) enzymes have been associated with increased miscarriage risk. While studies show diminished PTGS2-derived prostaglandins in the endometrium of patients with implantation failure, the role of PTGS2 during peri-implantation remains controversial in mouse models. Conflicting research suggests that PTGS2 knockout (Ptgs2-/-) mice show either comprehensive reproductive impairments or effects limited to ovulation. Furthermore, the specific uterine cell types involved in PTGS2 activity and its role in implantation chamber formation remain unclear. This thesis investigates prostaglandin's reproductive role through two complementary approaches in mouse models. First, we employed genetic deletion of PTGS2 in specific uterine cell types using multiple mouse models: Ptgs2-/- (global deletion), Ltfcre/+; Ptgs2f/f (uterine epithelial deletion), Pax2cre/+; Ptgs2f/f (uterine epithelial and endothelial deletion), and Pgrcre/+; Ptgs2f/f (deletion in ovary, oviduct, uterine epithelium, stroma, and circular smooth muscle). Second, we used pharmacological inhibition through NSAIDs: Aspirin (PTGS1-specific), Dup-697 (PTGS2-specific), and indomethacin (PTGS1 and PTGS2 inhibitor). Both approaches were enhanced by three-dimensional (3D) imaging techniques to evaluate uterine tissue remodeling during peri-implantation. Using tissue-specific knockout models, we demonstrate in Chapter 3 that deletion of PTGS2 in uterine stroma using Pgrcre/+; Ptgs2f/f impairs multiple reproductive processes: timely embryo implantation, post-implantation embryonic development, implantation chamber formation, vascular remodeling, decidualization, and overall pregnancy success. In contrast, epithelial and endothelial PTGS2 deletion shows no significant impact on these processes. Our analysis of NSAID effects in Chapter 4 reveals critical timing windows for PTGS activity during pregnancy establishment. Specifically, indomethacin treatment results in delayed implantation, disrupted embryo spacing, restricted embryonic growth, impaired implantation chamber formation, and vascular remodeling. These findings advance our understanding of prostaglandin signaling regulation during early pregnancy with important clinical implications. Understanding the cell type-specific and temporal requirements for prostaglandin signaling could help resolve controversies surrounding NSAID use during pregnancy and guide the development of safer anti-inflammatory therapy protocols. Additionally, variations in prostaglandin signaling across populations may explain differential susceptibility to implantation failure, highlighting the importance of personalized care approaches for optimal pregnancy outcomes.Description based on online resource. Title from PDF t.p. (Michigan State University Fedora Repository, viewed ).Includes bibliographical references
INTEGRATING TRANSFORMATIVE SOCIAL EMOTIONAL LEARNING AND LITERACY WITH READ ALOUDS : A DESIGN BASED STUDY
Get PDFThesis (Ph.D.)--Michigan State University. Curriculum, Instruction, and Teacher Education - Doctor of Philosophy, 2025This dissertation presents a design-based research study that utilized qualitative data analysis to investigate justice-oriented approaches to integrate transformative social-emotional learning (TSEL) with interactive read-alouds to simultaneously support elementary students\u2019 social-emotional and literacy development. In this study, I collaborated with a fifth-grade teacher during the 2022-2023 and 2023-2024 school years to iteratively design, enact, and revise an approach we are calling Read Alouds for Social Emotional Learning (RASEL) across two rounds of implementation. More specifically, the goals of my study were (1) to explore in what ways (if any) fifth-grade students demonstrate changes in components of social-emotional learning and narrative reading comprehension before and after participation in the instructional sequence and (2) to determine the aspects of RASEL instruction that enhance or inhibit the integration of students\u2019 SEL and literacy development based on the experiences of one fifth-grade teacher and a group of anchor students. Across three iterative and flexible phases within the DBR process (analysis and exploration, design and construction, and evaluation and reflection), we developed RASEL, which includes a series of interactive read-alouds using high-quality culturally relevant text sets focused on corresponding social-emotional themes such as self-awareness and social awareness. To answer my research questions, I analyzed my data set (student interviews and artifacts, teacher interviews and surveys, video observations, and researcher notes and memos) through an interpretivist approach. After participating in RASEL, students shifted in overlapping components of TSEL and narrative reading comprehension which include: exploring more complex emotion vocabulary, inferring emotions with evidence that highlights characters\u2019 cultural experiences, embracing the interrelated nature of their personal and social identities, recognizing injustices and acknowledging harm, and identifying themes from the text that advocate social justice. Additionally, my analysis highlighted three aspects of RASEL (feel wheel, identity silhouettes, and the text set) that enhanced the integration of SEL and literacy development and two aspects of RASEL (identity mapping and character perspective-taking) that inhibited the integration of SEL and literacy development.This study advances the field\u2019s understanding of the reciprocal relationship between social-emotional and literacy development. It also builds the growing body of TSEL research by offering actionable steps to teach against traditional notions of SEL with more authentic, humanizing, and culturally responsive TSEL integration. It highlights teacher expertise and student voices that contributed to the RASEL design, which shows promise as a framework for fostering social-emotional growth in ways that embrace culture, complexity, and justice.Description based on online resource. Title from PDF t.p. (Michigan State University Fedora Repository, viewed ).Includes bibliographical references
THE INTERSECTION OF CELL ENVELOPE MAINTENANCE AND METABOLIC VERSATILITY IN STAPHYLOCOCCUS AUREUS
Get PDFThesis (Ph.D.)--Michigan State University. Microbiology and Molecular Genetics - Doctor of Philosophy, 2025Adapting to changes in environmental conditions is an essential process that ensures maximal fitness of an organism is maintained. For bacterial pathogens residing in the host, these changes include alterations in oxygen availability, nutrient abundance, and the presence of antimicrobials. Failure to meet these challenges limits the pathogenic potential of the bacterium, therefore, a better understanding of how bacterial pathogens respond to environmental changes will aid the development of treatment strategies to combat microbial infections. Staphylococcus aureus is an opportunistic pathogen that employs a diverse set of metabolic pathways to adapt to new host environments and stressors, which is driven by a branched aerobic respiratory chain and the ability to transition into a fermentative state of growth known as the small colony variant (SCV). The branched respiratory chain is powered by two terminal oxidases, CydAB and QoxABCD, and loss of either terminal oxidase leads to tissue specific colonization defects. Infections caused by SCVs are often resistant to antibiotic treatment, frequently leading to prolonged infections with worse clinical outcomes for the patient. In line with the goal of identifying novel therapeutic targets, this dissertation explores the pathways supporting the metabolic versatility of S. aureus including synthesis of lipoteichoic acid (LTA) and the isoprenoid biosynthetic pathway. LTA is a cell surface polymer that has been predicted to maintain surface ion homeostasis. Previous reports demonstrated that limiting the metabolic potential of S. aureus cells in which LTA synthesis is disrupted reduces viability. Accordingly, we sought to determine the mechanism driving this phenotype. The membrane embedded anchor on which LTA is synthesized is generated by YpfP, and inactivation of this enzyme results in LTA that is elongated and less abundant. Membrane potential of the ypfP mutant was maintained during aerobic growth, however, induction of SCV growth resulted in a loss of membrane potential and reduced viability. Suppressor mutants in the ypfP mutant background that displayed increased SCV viability were isolated and characterized. The suppressor mutants exhibited LTA that was more similar to the WT and anaerobic membrane potential was partially restored, demonstrating that LTA supports SCV viability via maintenance of ion homeostasis. Further investigation of pathways supporting metabolic versatility identified the isoprenoid biosynthetic pathway as essential for cellular respiration. Isoprenoids are molecules containing 5-carbon repeating units and are synthesized by prenyl diphosphate synthases (PDS). Farnesyl diphosphate (FPP) serves as a substrate for three downstream cellular processes: pigment production, cell envelope maintenance, and synthesis of respiratory cofactors. The only known PDS to synthesize FPP is IspA, however, ispA mutants still produce FPP, suggesting another FPP-producing PDS is present. Investigation of this pathway identified a high level of redundancy in which other PDSs not previously known to produce FPP are able to contribute to FPP dependent pathways. Studying the effects of isoprenoid synthesis disruption on respiration revealed a preference of the CydAB terminal oxidase for chain length of menaquinone, demonstrating the impact of isoprenoid synthesis on metabolic versatility. Lastly, a chemical library screen was performed to identify inhibitors of the fatty acid kinase (FAK) system. The FAK system is used to acquire exogenous fatty acids and limits the efficacy of antimicrobials that target endogenous fatty acid synthesis. Disruption of these pathways limits the production of the fatty acids necessary for cell membrane synthesis and thus inhibits growth of the cell. A putative FAK system inhibitor was identified and demonstrated to work synergistically with triclosan, a known inhibitor of endogenous fatty acid synthesis. This work demonstrates the feasibility of a dual therapy strategy for inhibition of cell membrane synthesis and lays the groundwork for expanding the toolkit available for treatment of S. aureus infections.Description based on online resource. Title from PDF t.p. (Michigan State University Fedora Repository, viewed ).Includes bibliographical references
Examining the Relations of Micro- and Macro-Language Skills to Persuasive Writing Using Exploratory and Confirmatory Factor Analysis with Application of Generative Artificial Intelligence-Derived Feedback
Get PDFThesis (Ph.D.)--Michigan State University. Special Education - Doctor of Philosophy, 2025This dissertation explores the multifaceted development of persuasive writing skills among secondary school students, with an emphasis on fostering reasoning and argumentation skills essential for targeted writing tasks. Student-constructed essays serve as valuable instruments for assessing scientific literacy and higher-order thinking; however, their evaluation involves many complexities and is susceptible to potential biases and various sources of measurement error. This study addressed two primary objectives. First, it identified key features influencing persuasive essay quality by utilizing product-oriented measures to analyze both microstructural and macrostructural dimensions of writing. A latent structure of writing assessment was established, and measurement invariance was tested across students with differing special education statuses. Second, building on insights from this foundational investigation, automated feedback prompts were developed and implemented using GPT, facilitating AI-based scoring and feedback mechanisms. This research underscores the relevance of factor-analytic findings in addressing gaps related to predictive models and AI-driven content-generation tools, ultimately supporting personalized learning and adaptive written feedback. The implications of this study align with AI\u2019s expanding role in education, offering strategic insights into maximizing AI\u2019s utility for enhancing educational equity and instructional effectiveness. A promising approach involves leveraging factorial models to inform generative AI in delivering tailored feedback, thereby enhancing students\u2019 writing proficiency and overall performance.Description based on online resource. Title from PDF t.p. (Michigan State University Fedora Repository, viewed ).Includes bibliographical references
UPCYCLING WASTE PET THROUGH AMMONOLYSIS : KINETICS, HOMOGENEOUS CATALYSIS, AND PRELIMINARY PROCESS DESIGN
No full textThesis (Ph.D.)--Michigan State University. Chemical Engineering - Doctor of Philosophy, 2025This dissertation focuses on eliminating plastic waste through the chemical upcycling of poly(ethylene terephthalate) (PET) via ammonolysis. Model studies on dimethyl terephthalate (DMT) and bis(2-hydroxyethyl) terephthalate (BHET) establish kinetic parameters, with pseudo-first-order rate constants of k1\u2032 = 0.25 \ub1 0.02 h 121 and k2\u2032 = 0.11 \ub1 0.02 h 121 for DMT at 100 \ub0C, and k1\u2032 = 0.958 \ub1 0.076 h 121 and k2\u2032 = 0.359 \ub1 0.034 h 121 for BHET. Activation energies for ammonolysis are determined as Ea1 = 27.9 \ub1 2.2 kJ/mol and Ea2 = 37.3 \ub1 3.3 kJ/mol for DMT and Ea1 = 7.01 \ub1 0.65 kJ/mol and Ea2 = 13.74 \ub1 0.66 kJ/mol for BHET. The reaction is autocatalyzed by ethylene glycol (EG), with a 22-fold rate enhancement when EG is present in a 3:1 excess.Ammonolysis of waste PET thermoforms is conducted in methanol and ethylene glycol, with diffusion limitations quantified using particle sizes of 150\u2013250 \u3bcm, 250\u2013600 \u3bcm, and 1800\u20132500 \u3bcm. The estimated ammonia diffusivity in PET at 100 \ub0C is 1.37 \ub1 0.48
7 10 127 cm2/s, and diffusion effects reduce the reaction rate by an order of magnitude for millimeter-scale particles. To enhance profitability, the resulting terephthalamide (TPD) undergoes Hofmann rearrangement to produce p-phenylenediamine (PPD) and 1,4-diisocyanatobenzene (DCB). PPD serves as a precursor for Kevlar\uae synthesis from 100% recycled PET, while DCB reacts with polyols to produce phosgene-free polyurethanes, aligning with Green Chemistry principles. To test economic viability, a large-scale process of upcycling PET to PPD is modeled using ASPEN Plus. Two potential designs are discussed at three different scales of PET processed per day: 1 ton, 30 tons, and 100 tons. Preliminary design results for the 100 ton per day process show high profitability with internal rate of return of 51.5%! These findings enhance our understanding of PET ammonolysis, addressing diffusion barriers, optimizing reaction conditions, and developing scalable pathways for sustainable plastic recycling within a circular materials economy.Description based on online resource. Title from PDF t.p. (Michigan State University Fedora Repository, viewed ).Includes bibliographical references
Machine-Learning-Based Multi-scale Modeling for Complex Fluids
Get PDFThesis (Ph.D.)--Michigan State University. Computational Mathematics, Science and Engineering - Doctor of Philosophy, 2025Multi-scale modeling presents a long-standing challenge in computational mathematics and is pertinent to a wide range of applications in materials science, fluid physics, and chemical engineering. Predicting collective behaviors typically necessitates the integration of modeling dynamics across micro-scale (atomistic), meso-scale (kinetic), and macro-scale (continuum) levels, with the vast range of spatiotemporal scales posing a fundamental obstacle. Existing methods often rely on certain empirical constitutive closures or micro-macro coupling approaches. Despite their broad applications, modeling accuracy and efficiency are often challenged in real applications. This dissertation aims to develop data-driven approaches for constructing accurate and reliable reduced models of multi-scale systems based on first-principle descriptions. The first part, including Chapters 2 and 3, focuses on constructing meso-scale reduced models of polymer kinetics directly from the full molecular dynamics. Chapter 2 discussed the many-body effect on conservative force, which is important to accurately reproduce both the probability density function of the void formation in bulk and the spectrum of the capillary wave across the fluid interface. Chapter 3 discussed the state-dependence on memory kernel and demonstrated the essential role of the broadly overlooked state-dependency nature in predicting molecule kinetics related to conformation relaxation and transition. The second part, Chapter 4, focuses on building accurate macroscale models from microscale polymer kinetics through meso-scale Langevin dynamics. A non-Newtonian hydrodynamic model is given as an example, which shows some success in systematically passing the micro-scale heterogeneous polymer structural mechanics to the macro-scale hydrodynamics without human intervention.Description based on online resource. Title from PDF t.p. (Michigan State University Fedora Repository, viewed ).Includes bibliographical references
MUTANT MEDIA\u2013DEFORMING CODES OF HUMAN VARIATION BETWEEN 1904 AND 1964
No full textThesis (Ph.D.)--Michigan State University. English - Doctor of Philosophy, 2025This dissertation focuses on the social structures, laws, and censorship bodies that attempted to limit access to representations of bodymind variation in the first half of the 20th century. It begins by reading into the ways that disability and human variation is stigmatized through connections to queerness, colonized nations, and race. This dissertation focuses on three distinct media\u2013pulps, film, and comics\u2013and the laws which attempted to regulate them\u2013 \u201cugly laws,\u201d The Hays Code, and the Comics Code Authority. I argue that these regulatory strategies had a threefold impact on the representation of disability across media. First, they attempted to constrain and domesticate representations of disability as a private matter. Second, they created a spectacle of bodymind variation by continuously amplifying the threat of mutants on normative humanity. Third, they created a desire for mutant representation in audiences which blurred the line between a disgusting other and a desirable subject position. This dissertation follows the ways in which mutation and difference pivoted from the horrific and disgusting to a desirable identity among science fiction fans. The mutants of the pulps created a space in which bodymind variation shifted from a stigmatized subject position to a mantle of power\u2013a threat to those who seemed not to understand. Science fiction films rely on the introduction of anxieties\u2013through multiple sensoria\u2013that are connected to social and cultural values which must then be resolved by the conclusion of the film. Science fiction comics intertwine fear, disgust, and potential to circumnavigate the Comic Book Code of 1954, maintaining a space for bodymind variance through fraught practices. While mutant media between 1904 and 1964 rendered human variation as something to be sought out and consumed for pleasure, they also amplified eugenic assumptions about its threat to normative reproduction.Description based on online resource. Title from PDF t.p. (Michigan State University Fedora Repository, viewed ).Includes bibliographical references
A DEEP NEURAL NETWORK METHODOLOGY FOR TIMELINE MONITORING OF BRIDGES USING DRONES
No full textThesis (M.S.)--Michigan State University. Data Science \u2013 Master of Science, 2025The US transportation network relies heavily on bridges, with over 40% being older than 50 years, as reported in the 2021 ASCE infrastructure report card. Traditional bridge monitoring is slow, labor-intensive, struggles with accessibility, and can be inconsistent, hindering proactive condition monitoring. To overcome these limitations, transportation agencies are investigating new technologies for inspections to improve access, reduce costs, and enhance safety. This research explores using drones and deep neural networks to create a system for detecting and tracking infrastructure damage. The study focuses on a bridge deck with patched patched spalling, using drones to capture images and deep learning models to identify and measure the extent of the damage over time. The study\u2019s methodology goes beyond simply locating damage by quantifying changes in the affected surface area. Experiments on simulated damage showed that both U-Net and SAM can generate accurate distress maps, which are crucial for estimating the progression of patched spalling during timeline monitoring. The developed methods and methodology can be expanded and applied to monitor other types of infrastructure damage, enabling proactive maintenance.Description based on online resource. Title from PDF t.p. (Michigan State University Fedora Repository, viewed ).Includes bibliographical references
WELLBEING AND NATURE-CONNECTEDNESS AT MID-MICHIGAN'S FARMER\u2019S MARKETS
No full textThesis (M.S.)--Michigan State University. Community Sustainability-Master of Science, 2025ABSTRACTFarmer\u2019s markets provide myriad benefits, including access to fresh produce, community building, opportunities for emotional exchange, and knowledge sharing (Alia et al., 2014; Joseph & Seguin, 2023; Warsaw et al., 2021). They can also provide an accessible entrance to the natural world by providing opportunities to interact with seasonal produce, land workers, and an even plant and animal life (Dowler et al., 2009; Morales, 2011). Moreover, the experience of being outdoors and shopping in a more leisurely manner can contribute to eudemonia and improved psychological health for some consumers (Joseph & Seguin, 2023; Russomanno & Jabson Tree, 2021). Independently, these outcomes are all worthwhile contributions to human health and wellbeing. But recent literature suggests that farmer\u2019s markets might also contribute to a more holistic kind wellbeing, which honors the mutual flourishing between humans and the natural world. Tied to nature connectedness and rooted in the innate human desire to connect with nonhuman nature (Capizzi & Kempton, 2023; Kellert & Wilson, 1994; Wilson, 1983), this social-ecological approach to wellbeing is a foundation of sustainability attitudes and action. But little empirical work has explored the intersection of wellbeing and nature-connectedness at farmer\u2019s markets. This project investigates the impact of the farmers market experience related to nature-connectedness and eudemonia- which describes the ways humans flourish (Jenkins et al., 2022) at three farmers markets in the greater Lansing area: The Allen Farmer\u2019s Market, Abbott Park Farmer\u2019s Market, and Meridian Market. Using interviews and observations, this study investigates: (1) the impact of the market experience on customer connections to the food system, nature, and/ or the community; (2) customer perceptions about the relationship between their market attendance and personal wellbeing; (3) the intersection between nature-connectedness and wellbeing at the farmer\u2019s markets. This project contributes to scholarly dialogue about nature-connectedness and wellbeing related to farmer\u2019s market attendance.Description based on online resource. Title from PDF t.p. (Michigan State University Fedora Repository, viewed ).Includes bibliographical references