K-State Electronic Theses, Dissertations, and Reports: 2004 -

Permanent URI for this collectionhttps://hdl.handle.net/2097/4

This is the collection for doctoral dissertations and masters theses and reports submitted electronically by K-State students. Electronic submission of doctoral dissertations was required beginning Fall semester 2006. Electronic submission for masters theses and reports was required beginning Fall 2007. The collection also contains some dissertations, theses, and reports from the years 2004 and 2005 that were submitted during a pilot test project. Some items before 2004 have been digitized and are available in K-State Electronic Theses, Dissertations, and Reports: pre-2004. Check the Library catalog for dissertations, theses, and reports not found in these collections.

All items included in this collection have been approved by the K-State Graduate School. More information can be found on the ETDR Information Page. Items within this collection are protected by U.S. Copyright. Copyright on each item is held by the individual author.

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Open Access
How millennials describe their decision-making process to leave their careers in agronomy retail in the Midwest region of the United States
(2025) Brenny, Katie
Millennial career decisions in agronomy retail reflect a dynamic mix of developmental, motivational, and contextual factors. This study investigates why millennials in the Midwest are leaving careers in this sector, focusing on how personal values, life stages, and workplace practices shape professional satisfaction and transitions. As rural agribusinesses face challenges in retaining younger talent, understanding these decisions is vital for sustaining the agricultural workforce. Grounded in Super's Life-Span, Life-Space Career Theory and Self-Determination Theory, the research combines developmental and psychological lenses to frame millennial career behavior. The study uses a qualitative design, with purposive sampling of 12 former agronomy retail employees in the Midwest. Data were collected through semi-structured interviews, concept maps, and analytic memos, then analyzed using an a priori coding strategy informed by existing literature. Findings reveal that work-life balance, limited growth, misaligned culture, and shifting personal priorities drove participants' exits from the sector. These insights challenge assumptions about generational loyalty in rural industries and underscore the need for agronomy retail to evolve alongside workforce expectations. This study contributes to theory and practice by clarifying how identity, motivation, and environment intersect in career decisions, laying the groundwork for more responsive and sustainable retention strategies in agriculture.
Open Access
Exploring Gender Differences in Retirement Preparedness Behaviours in Canada: A Health Belief Model Approach to Understanding Perceived Motivators, Barriers and Behavioural Moderators
(2025) Staples, Tanya M.
Women increasingly play a pivotal role in personal wealth in Canada, controlling more than $2 trillion in financial assets; a value projected to double within the next five years. Unfortunately, Canadian women are plagued by unique financial challenges such as lower earnings levels, disrupted career patterns, investment risk aversion, lower financial knowledge, increased longevity and increased incidents of financial insecurity. Using the health belief model this study explores the motivators driving retirement preparedness behaviours of women, focusing on perceived barriers, benefits and threats. Using the 2019 Canadian Financial Capabilities Study (CFCS) this dissertation employs a quantitative approach using a one-paper, four model framework. Statistical methods include path and regression analysis as well as moderation testing. By identifying gender-specific barriers and motivators that influence retirement preparedness behaviours, actionable recommendations can be developed for practitioners and policymakers to improve retirement outcomes for all Canadians, particularly women. Additionally, this dissertation contributes to the literature on financial knowledge, behavioural psychology, and gender-specific financial and retirement planning strategies.
Open Access
Navigating borders and transgressing boundaries: A feminist autoethnography
(2025) Louis, Heidi
In this autoethnography, I explore the intersections of my lived experiences, systemic inequity, and educational practice through the lens of critical feminism. Grounded in my encounters with the carceral system and punitive school discipline, this study examines how those experiences shape my philosophy, leadership, and commitment to restorative justice in education. Guided by three questions—how my experiences with the carceral system and punitive discipline inform my educational practice, and how my understanding of discipline evolves across the intersectional spaces of my life—I use critical reflection and narrative inquiry to analyze the personal and political dimensions of schooling and justice. Through this process, I position myself as both researcher and subject, interrogating the carceral logics embedded in educational systems and illuminating the transformative potential of restorative approaches. My analysis reveals that growth and understanding emerge through self-examination, resistance to oppressive structures, and the reclamation of voice and agency. This study contributes to the broader discourse on educational equity by centering lived experience as a site of knowledge production and by advocating for practices rooted in empathy, relational accountability, and systemic transformation.
Open Access
Evaluating the robustness of 3-D space-carving seed reconstruction under image noise
(2025) Chandana, Pavan
Three-dimensional (3-D) seed reconstruction is a critical component of automated plant phenotyping, enabling accurate measurement of seed volume and surface morphology from multi-view image data. Among various reconstruction approaches, space carving provides a simple yet powerful voxel-based method that integrates multiple binary silhouettes to estimate the true object geometry. However, the accuracy of such reconstructions depends strongly on the quality and consistency of the image masks used as input. In practical imaging pipelines, image errors arise unavoidably due to lighting variation, sensor artifacts, and imperfect thresholding or learning-based models. This study investigates the robustness of 3-D space-carving reconstruction under con trolled iamge perturbations. A single wheat seed was imaged from 36 viewpoints at 10◦ intervals, and reconstruction was performed using the first 10 silhouettes—sufficient for con vergence of the carved volume—via the multi-threaded carving algorithm of Nielsen1. Binary masks were systematically modified using three perturbation types: morphological erosion, morphological dilation, and random salt-and-pepper noise. A 3 × 3 kernel was applied, and the percentage of pixels altered (0.2–1.0%) was varied to ensure consistent noise scaling across all perturbation modes. The results show that space carving is highly stable under both erosion and dilation, with minor deviations even at the highest perturbation levels, confirming robustness to moderate under- and over-segmentation. In contrast, salt-and-pepper noise caused large deviations in surface area (up to 150%) and moderate reductions in volume (about 13%) due to the formation of small holes and fragmented silhouettes. These findings reveal that while the method is resilient to smooth boundary variation, it is highly sensitive to loss of silhouette connectivity.
Open Access
Evidence-based approaches to health risk mitigation and value creation in U.S. livestock production systems
(2025) de Aguiar Veloso, Vanessa
The U.S. livestock industry faces increasing pressure to balance productivity, economic efficiency, and sustainability while minimizing disease risks, antimicrobial use, environmental impacts, and animal welfare concerns. This dissertation applies epidemiological and economic principles to enhance evidence-based decision-making for managing agricultural risks across diverse livestock systems. Agricultural risks are commonly categorized as financial, institutional, human resources, market, and production risks. Yet, effective management goes beyond objective classifications; it also requires an understanding of how producers and other stakeholders perceive and interpret these risks. Perceptions shape how risks are prioritized, and which management strategies are adopted, influencing outcomes at both the farm and industry levels. Outcomes research provides a framework for integrating scientific evidence with practical decision-making in livestock systems. By applying clinical and population-based methods to evaluate the effectiveness and value of interventions, it bridges the gap between research and practice, reduces uncertainty, and strengthens the producers’ capacity to manage agricultural risks through informed, evidence-based strategies. These concepts are described and discussed in Chapter 1. Chapter 2 is a rapid systematic review synthesizing knowledge on the role of swine in the transmission dynamics of Japanese encephalitis virus (JEV), diagnostic methods, and preventive and surveillance strategies. The review highlights key data gaps in the potential role of feral swine in JEV transmission, identifying priorities for U.S. surveillance and preparedness to mitigate the risk of JEV introduction and establishment. A survey design was employed in Chapter 3 to characterize veterinarian and feedlot manager perceptions and decision-making considerations regarding metaphylaxis use for cattle at moderate risk of bovine respiratory disease. The study identifies both alignment and divergence in how disease risk, information access, and management priorities influence antimicrobial use, underscoring opportunities to improve communication and support antimicrobial stewardship within feedlot systems. In Chapter 4, observational auction market data were used to evaluate the economic impact of value-added management programs on feeder calf sale prices. Through regression modeling, the study estimates price premiums associated with specific program combinations and illustrates how information asymmetries may influence market efficiency and producer decision-making capacity. Together, these studies emphasize the central role of information — derived from diverse data sources and research approaches — in improving disease risk management and supporting sustainable livestock production. With them, the need for continued investment in data integration, traceability systems, and communication frameworks that enhance transparency (or information access) and evidence-based practice is highlighted. Strengthening information networks will be essential for improving efficiency and profitability, adapting to evolving societal values, and ultimately promoting the resilience of U.S. livestock systems.
Open Access
Voices from the margins: The organizational support experience of adjunct faculty at a multi-campus community college
(2025) McNeil, Zack
This interpretive phenomenological study explores the organizational support experiences of adjunct faculty at a multi-campus community college. As adjunct faculty increasingly comprise most instructional staff in U.S. community colleges, understanding their lived experiences is essential to improving institutional effectiveness and student outcomes. By examining institutional structures and the social dynamics between adjunct faculty and their colleges, the study investigates how adjunct faculty perceive support and identifies systemic challenges that influence their performance and well-being. Data was collected through three rounds of semi-structured interviews with 11 adjunct faculty members across four campuses. Thematic analysis revealed four central themes: (a) communication, (b) isolation, (c) overwhelmed, and (d) recognition. Participants described fragmented and impersonal communication, limited access to resources, emotional fatigue, and a lack of meaningful inclusion in institutional culture. Despite these challenges, adjunct faculty expressed a strong commitment to teaching and a desire for more equitable support. Findings suggest that adjunct faculty effectiveness is not inherently inferior to full-time faculty but is shaped by disparities in organizational support. Recommendations include: (a) improving communication practices, (b) fostering community, (c) managing workloads, and (d) embedding recognition into institutional policy. The research contributes to the literature on adjunct faculty by centering their voices and offering actionable strategies for enhancing their support experience. The implications extend beyond the study site, offering insights for other colleges seeking to improve adjunct faculty engagement, retention, and student success.
Open Access
Salmonella enterica in internal organs of cattle and comparative growth of Fusobacterium necrophorum subspecies and Fusobacterium varium in lactate- and/or lysine-based enrichment media
(2025) Baghaei Naeini, Farinaz
This report provides a review of prevalence and distribution of Salmonella enterica in internal organs of cattle and two experimental studies on Fusobacterium species associated with liver abscesses. The review highlights that S. enterica primarily colonizes the gastrointestinal tract of cattle and can also spread to internal organs such as the lymph nodes, liver, and lungs, where it can persist as hidden reservoirs, often causing asymptomatic infections that contribute to beef contamination during slaughter. Among the major serotypes of S. enterica, S. Dublin, S. Typhimurium, and S. Newport are frequently linked to systemic infections and foodborne outbreaks. The review includes the zoonotic significance of Salmonella, its persistence in internal organs, and the challenges of controlling contamination in beef production systems. Key preventive strategies include improving farm hygiene, strengthening biosecurity, vaccination, and adopting proper processing and handling practices to reduce bacterial transmission and protect public health. Chapter 2 focuses on Fusobacterium necrophorum and F. varium involved in bovine liver abscesses and includes two experimental studies. The study 1 was on the detection and quantification of F. necrophorum subsp. necrophorum and F. necrophorum subsp. funduliforme in bovine tissues (healthy livers, abscessed livers, ruminal epithelial and colonic epithelial) and comparison of three enrichment media, Peptone-Yeast extract with lactate, lysine or both; PY- La, Py-Ly, and PY-La-Py). The enrichment containing both lactate and lysine yielded the highest recovery of F. necrophorum subspecies, especially from ruminal and colonic tissues, while lysine broth was most effective for liver abscesses. The study 2 was on comparative growth of F. necrophorum subsp. necrophorum, F. necrophorum subsp. funduliforme, and F. varium in PY- La, PY-Ly, and PY-Ly-La broths, which examined bacterial growth under anaerobic conditions and found that both F. necrophorum subspecies grew best in PY-Ly-La broth, while F. varium exhibited the highest growth in PY-Ly broth, indicating distinct substrate utilization patterns. Together, these findings demonstrate that Salmonella and Fusobacterium are major pathogens impacting cattle health and in addition, Salmonella is a major foodborne pathogen with implications in beef safety. Understanding the persistence of Salmonella in internal organs provides insight for developing more effective control and monitoring programs, while identifying the most effective enrichment medium capable of detecting and quantifying low concentrations of Fusobacterium provides a more accurate insight into its distribution in cattle tissue samples
Open Access
Consumer Interest in Purchasing Products Made In-Country vs. Imported Products & Its Relationship with Consumer Ethnocentrism
(2025) Kroll, Ryan
With the rise of a global economy, instead of marketing to national consumers, companies sought to create international marketing plans as a way for consumers in other nations to experience a slice of life from their country of origin. With the click of a button, the demand for products such as Levi’s and Coca-Cola grew, and consumers now had the option to purchase international or domestic products. While some consumers openly accepted the variety of international products, others rejected them, sometimes with ethnocentric tendencies, finding it unpatriotic to support an international brand. To investigate the relationship between country of origin and ethnocentrism, an online survey was developed for thirteen countries, to capture consumers' interest and cost value on purchasing ten different food and beverage products. The purpose of this research is to investigate whether the relationship between country of origin and ethnocentrism exists with specific products or countries.
Open Access
Technologies and practices to improve feed and nutrient utilization by pigs
(2025) Navales, Ron Aldwin
In chapter 1, a literature review was conducted to summarize the current practices that producers can use to improve feed and nutrient utilization with a focus on providing critical information for use within future life cycle assessment of the swine industry. These practices include improvement of feed efficiency and nutrient utilization by pigs through diet nutrient levels, feed formulation, feed processing, feeding management, and non-nutritional factors such as genetics, environment, and health status. Research needs were also identified, with some investigated in chapters 2 to 4. Specifically, a total of two, one, and four trials were conducted to compare diet blending with phase feeding on growth performance and profitability of finishing pigs (Chapter 2), to determine the available P and total tract digestible P release curves for a novel phytase (Microtech phytase, Chapter 3), and to determine the effect of standardized ileal digestible (SID) Lys to crude protein (CP) ratio on growth performance and blood urea N of 45 to 125 kg pigs (Chapter 4). In Chapter 2, a total of 2,160 and 962 pigs were utilized in 2 experiments. Two feeding strategies (phase feeding and diet blending) were compared and concluded that both supported similar growth and carcass traits. Income over feed cost was generally unaffected, but diet blending reduced feed usage and feed cost per kg gain. In Chapter 3, a total of 320 barrows were used. Overall, the use of Microtech phytase improved growth performance. Additionally, the available P (aP) release curve based on the average percent bone ash of right fibula, 10th rib, and 3rd metacarpal and true total tract digestible (TTTD) P release curve developed for Microtech phytase are: aP release, % = (0.868 × FTU/kg) ÷ (9,599.511 + FTU/kg) and TTTD P release, % = (0.00004017 × FTU) + 0.011, respectively. In Chapter 4, a total of 2,517 pigs were used across 4 experiments. Overall, increasing SID Lys:CP ratio worsened gain to feed ratio and decreased blood urea N in 45 to 125 kg pigs. Based on the local maxima determined using cubic models, the estimated SID Lys:CP ratios to optimize gain to feed ratio were 5.55% (45 to 70 kg), 5.47% (55 to 78 kg), and 5.27% (103 to 125 kg). For 84 to 108 kg pigs, requirements were estimated below 5.13% (linear model). Overall, chapters 2 to 4 underscore the opportunities to improve feed and nutrient utilization through feeding strategy, diet formulation (i.e., use of phytase), and nutrient levels. Diet blending allows for reduction in feed usage while maintaining growth, phytase allows for reduction in the use of inorganic P and determining the optimum SID Lys:CP ratio allows for formulating low CP diets. This dissertation also evaluated the effect of dietary S-abscisic acid (S-ABA) supplementation on the growth performance and antioxidant status of nursery pigs (Chapter 5). A total of 320 nursery pigs were used and supplemented with increasing level of S-ABA. Overall, S-ABA supplementation did not influence growth performance, but improved the antioxidant status by reducing the erythrocyte oxidized to reduced glutathione ratio. In addition to the dissertation chapters, a retrospective study was added as an appendix, assessing the impact of sow body weight (BW) change during gestation on sow body weight change and litter average daily gain (ADG) during lactation. The dynamics of sow BW change during gestation and lactation significantly influenced litter ADG. Increased BW gain in gilts during gestation led to greater BW loss in lactation without negatively affecting litter ADG, whereas BW loss in sows during gestation led to compensatory gain during lactation at the expense of litter ADG.
Open Access
Nutritional strategies to optimize growth performance in nursery pigs
(2025) Arroyave Jaramillo, Julian
Optimizing dietary strategies in pigs is crucial to enhance growth performance, nutrient utilization, and economic efficiency while minimizing environmental impact. A total of nine experiments (5,423 pigs) and a meta-regression analysis structured in 5 chapters were used to evaluate the effect of Zn levels and sources under different formulation strategies, nursery feed budgets, and a functional fiber ingredient on growth performance, fecal dry matter (DM), mineral excretion, and economic outcomes. In chapter 1, a meta-regression analysis utilizing data from 51 published papers was conducted to identify dietary factors associated with Zn excretion in pigs and develop predictive models for Zn excretion. Principal component analysis indicated that nutrient intake variables, including minerals, fiber, nitrogen, as well as body weight and feed intake, accounted for a significant portion of the variability in Zn excretion. Overall, Zn intake was the primary determinant of fecal Zn excretion, with meta-regression models predicting that 61% of Zn intake is excreted when diets meet the requirement and up to 82% when Zn exceeds requirement estimates. In Chapter 2, two experiments utilizing 2,268 pigs were conducted to evaluate the effects of Zn source (ZnO, Zn hydroxychloride, ZnSO4, or chelated Zn) and inclusion level on growth performance, fecal DM, fecal Zn concentration, and carcass characteristics. In nursery pigs, increasing dietary Zn led to higher fecal Zn concentrations independent of the Zn source, although overall growth performance and fecal DM were unaffected by Zn source or level. In finishing pigs, Zn source did not affect growth performance, carcass weight, or carcass yield, with only marginal effects observed on backfat depth and lean percentage in favor of Zn hydroxychloride. Chapter 3 utilized 360 nursery pigs to evaluate the impact of dietary acid-binding capacity to pH 4 (ABC-4) and Zn levels on growth performance, fecal DM, and Zn excretion. At the same dietary Zn concentration, low ABC-4 diets enhanced Zn absorption, apparent total tract digestibility of Zn, and fecal DM at early stages, although overall growth performance was not significantly affected by dietary ABC-4. Increasing Zn in low ABC-4 diets improved ADG and ADFI during the experimental period; however, these differences did not translate into a better overall performance. Furthermore, d 24 fecal Zn excretion and serum Zn concentration increased with dietary Zn, validating the results from chapter 1, where the main determinant of fecal Zn excretion was the dietary Zn concentration. Chapter 4 was composed of two experiments that utilized a total of 1,800 pigs to evaluate the effect of nursery feed budget on growth performance and economics. Experiment 1, which was conducted in university research facilities, demonstrated that reducing the budget of complex phase 1 and 2 diets did not affect overall pig performance but improved economic outputs. To confirm these findings, a second experiment was conducted in a commercial research facility. While pigs provided a reduced feed allowance and less complex diets tended to grow slower in the early nursery period, no differences in growth performance were observed by d 63 after weaning. Collectively, these findings suggest that reducing early nursery feed budgets could be a strategy to improve economic outcomes without compromising long-term pig growth. Chapter 5 was composed of three experiments utilizing a total of 995 pigs to evaluate the effect of ValoproWin (VLPW), a functional fiber ingredient composed primarily of insoluble, poorly fermentable fiber, on growth performance and fecal DM in nursery pigs. Within three experiments, sub-objectives were to determine how the response was impacted by: (1) VLPW feeding duration and dietary ABC-4; (2) VLPW inclusion level; and (3) potential interactions between VLPW inclusion level and dietary formulation strategies (nutrient dilution vs. nutrient adjustment). Considering the results of the three experiments collectively, the inclusion of VLPW had minimal effects on growth performance; however, it may serve as a nutritional strategy to promote intestinal health and increase fecal DM.
Open Access
Alpha-gal syndrome: public awareness, lived experiences, and health provider perspectives on plant-based nutrition
(2025) SEMPA, JUDITH
There is a global rise in allergic conditions and multimorbidity. Historically, these have been treated as separate clinical entities however, emerging research indicates they share similar immunological roots primarily immune dysregulation. Alpha-gal syndrome (AGS), a tick-borne allergy triggered by lone star tick bites, is increasingly prevalent in the Southern, Eastern and mid-western regions of the United States including Kansas. Simultaneously, 10.2% of adults in Kansas experience multimorbidity (defined as having two or more chronic conditions such as obesity, chronic kidney disease, cardiovascular disease, cancer etc.). This study explored AGS awareness, distribution, lived experiences and systemic challenges faced by Kansans living with AGS. Using a mixed methods approach, the study included two anonymous surveys targeting Kansas community residents and Extension professionals, as well as in-depth interviews with thirty AGS-affected individuals. Findings revealed that while general awareness of AGS is growing, significant challenges remain related to dietary restrictions and adaptations, psychosocial challenges, financial burdens and gaps in healthcare support. Participants frequently relied on self-management and self-advocacy due to limited health professional knowledge and support, underscoring the need for improved medical education, clearer food labeling, and access to more support and resources. Our study found that many individuals with AGS adopted plant-based diets (PBDs) as a practical strategy for managing their condition. Emerging evidence indicates that PBDs, rich in antioxidant and anti-inflammatory compounds, can enhance gut health, support immune function, and reduce risk of chronic diseases by mitigating chronic systemic inflammation. Building on this insight, the third phase of the study examined health professionals’ readiness to support individuals following PBDs. A narrative review of 27 studies identified key barriers and enablers related to integration of PBDs in routine patient care which included: time constraints, limited educational resources, insufficient skills, limited interdisciplinary collaboration, and inadequate professional training. The study findings suggest that access to evidence-based research summaries, clear guidelines, ongoing professional development, and other relevant educational resources were crucial for equipping healthcare professionals to support individuals adopting PBDs which would benefit individuals managing AGS as well as those dealing with chronic diseases such as obesity, diabetes and cardiovascular disease. Overall, this study highlights two seemingly distinct yet interconnected public health challenges: (1) AGS, an emerging allergic condition that has become a leading cause of adult-onset allergies and anaphylaxis in high-prevalence areas; and (2) the critical need to equip healthcare professionals to effectively support individuals adopting a plant-based lifestyle. Given the growing body of evidence linking immune dysregulation to both allergic conditions and chronic disease pathogenesis, better understanding and integration of plant-based nutrition may offer dual benefits in the prevention and management of both.
Open Access
Equity in transit-oriented development (TOD): A thematic and policy analysis of Chicago’s plans
(2025) Hughes, Jessica
This research analyzes the extent to which the priorities of Chicago’s regional transit-oriented development (TOD) plans address equity-related concerns. While TOD is promoted as a sustainable urban tool, offering benefits such as increased transit accessibility, modernization, and walkability, there are potential equity concerns. As cities adopt TOD strategies to improve public transit access and mobility, there have been critiques about who benefits and who does not. This qualitative research utilizes existing secondary data from five Chicago region plans, published between 2010 and 2022. Using thematic and policy analyses, similar themes and policy recommendations were identified to understand how Chicago frames and addresses priorities, rather than evaluating outcomes from policy implementations. All five plans agreed that key priorities are the preservation of affordability, increasing mobility, strengthening the transit system, accessibility, and expanding pedestrian-friendly communities. The plans published from 2010 to 2016 did not prioritize equity but had broader goals for regional transportation. In contrast, the plans published from 2018 to 2022 shifted the region’s focus towards equity. This research aims to contribute to ongoing conversations about the effects of transit investments and whether Chicago mitigates or reinforces patterns of spatial inequalities, or if they represent equitable and inclusive development.
Embargo
Synthesis and characterization of molecular probes for various enzymes
(2025) An, Chao
Enzymes are the cell’s precision machinery, translating molecular recognition into chemistry that governs genome maintenance, signaling, metabolism, immunity, and materials turnover. Because small shifts in their activity can cascade into system-level outcomes, enzymes are both mechanistic readouts and therapeutic entry points. Molecular probes turn that duality into experiments: they bind the right target, reach the right compartment, and report in a way that answers a concrete question. This dissertation integrates synthesis and characterization to build molecular probes and use them to interrogate distinct enzyme classes. Chapter 1 frames scientific motivation and organizational logic. Because the target enzymes differ in fold, chemistry, and biological context, a single modality cannot answer all questions, the work is organized into the following four application-focused chapters: Chapter 2 develops heterobifunctional degraders against the N-terminal methyltransferase NTMT1. Following the canonical PROTAC design, a protein of interested ligand is linked to an E3 ligase recruiter to form productive ternary complexes that drive ubiquitination and proteasomal clearance. A focused 2.45 series establishes linker geometry as the controlling variable: in HEK293FT cells, selected members (2.45I– K) produce time-dependent depletion of NTMT1, whereas closely related analogs (2.45G–H) trigger cytotoxicity—an instructive reminder that permeability, polarity, and off- target degradation are finely balanced. These data validate NTMT1 degradability and map a practical route for optimization. Chapter 3 repurposes Thioglo-1 as an active-site probe and inhibitor for Class I PHA synthases (PhaC_Re, PhaC_Cc, PhaC_Cs). Under harmonized assays, Thioglo-1 shows clear, dose- and time-dependent inhibition of PhaC_Cc and PhaC_Re, but not PhaC_Cs. Divergence likely reflects differences in active-site accessibility or CAP-domain dynamics and positions Thioglo-1 as a selective tool to rank active-site exposure across homologs and to track covalent blockade during polymerization. Chapter 4 addresses materials access for heme-enzyme engineering by providing a concise, high-yield synthesis of Nδ -methyl-histidine (NMH). Installing a sulfonamide (N– SO₂Ph) on Boc-His-OMe enables MeOTf-mediated, regioselective Nδ -methylation, followed by basic advance and acid deprotection to deliver NMH in >95% HPLC purity. Ready availability of NMH lowers the barrier to tuning Fe–His coordination and reshaping the “push–pull” landscape in heme catalysis. Chapter 5 delivers a practical synthesis and purification of Z-Gly-Arg-thiobenzyl ester, a staple chromogenic substrate for trypsin-like complement proteases (C1r/C1s). An initial route failed due to thioester lability under piperidine deprotection; the optimized sequence installs SBzl last and couples strategic work-ups with preparative HPLC to obtain a single, stable product. Together, these chapters underscore a single principle: when synthesis is aligned with the biological question, molecular probes become decisive tools—enabling targeted degradation, covalent mapping of active sites, electronic tuning of metalloenzymes, and reliable enzymatic assays that generalize beyond a single system.
Open Access
Fostering partnerships: an autoethnographic study of collaboration between a hearing, signing teacher of the deaf and two American Sign Language interpreters
(2025) Willhite, Danielle
As the population of deaf and hard-of-hearing (DHH) students in mainstream classrooms continues to grow (Luckner & Muir, 2001b; Stinson & Antia, 1999), effective collaboration among specialized professionals is increasingly vital (Antia & Kreimeyer, 2001b; Cogen & Cokely, 2015). This critical-interpretive autoethnographic study examined my experiences as a hearing, signing teacher of the deaf (TOD) working with two American Sign Language (ASL) interpreters within a self-contained DHH science classroom. Grounded in Tuckman’s (1965; Tuckman & Jensen, 1977) stages of group development, this research explored how our teamwork unfolded through the stages of forming, storming, norming, performing, and adjourning (Bonebright, 2010). Data collection employed triangulation (Creswell & Poth, 2018; Denzin, 1978) through reflective video journals, structured interpreter interviews, and document analysis of job descriptions and professional development records (Schick, 2007; Seal, 2004). Findings revealed that strong rapport and shared signing fluency supported smooth norming and performing, and role ambiguity, mismatched preparation, and feedback tensions emerged during storming and adjourning, highlighting the emotional labor involved in navigating daily collaboration. Divergences between my perspective and the interpreters’ insights exposed systemic barriers and the need for clearer role negotiation and joint professional learning (Cogen & Cokely, 2015; M. B. Smith & Ramsey, 2010). By situating these personal reflections within broader cultural and institutional contexts, I offered insights that illuminate the complexities of role clarity and teamwork and highlight ways to foster more equitable collaboration that can support improved educational access for DHH students in inclusive settings (Antia et al., 2002).
Open Access
Sustaining the S.P.A.R.K. (Supporting Parents Anticipating Resilient Kids): A study on program implementation during the transition to parenthood
(2025) Wehling, Anna
The intent of this study was to obtain feedback on a new and innovative intervention designed to help romantic partners sustain fulfilling relationships throughout the transition to parenthood called Sustaining the SPARK (Supporting Parents Anticipating Resilient Kids). Four formative evaluation approaches were used to assess: (a) therapists’ satisfaction with the program training, (b) the value propositions that would best motivate therapists to become trained in the program, (c) what parents of young children think is important for program effectiveness, and (d) the experiences of expectant parents going through the program. First, graduate couple and family therapy student therapists (n = 3) reported after being trained in the curriculum they were the most comfortable with the values topic of the curriculum, followed by the topics of emotion regulation and finances/financial goals, which were tied. Finally, conflict resolution, expectations, and gender roles/labor division were ranked as topics therapists were least comfortable with. All three trained therapists reported they were satisfied or very satisfied with the quality of the training in a variety of areas, but rated engagement and interactive aspects of the training the lowest, which provides a clear focus for further training improvements. Second, the market testing to 22 therapists in the K-State Couple and Family Therapy Program explored which values would be most effective in motivating therapists to enroll for training and program dissemination. The statement that included an appeal to therapists’ passion for helping couples was ranked as the most motivating. Additional qualitative feedback identified that therapists were motivated most by statements with positive language and emotional tone, and they were least motivated by statements that did not highlight their clinical interests or values (e.g., money-focused). Third, our focus group of parents with children under 4 years-old (n = 4) provided qualitative feedback on Sustaining the SPARK. Feedback revealed themes related to factors that may help participants attend and remain engaged in the program, the importance of focusing on partners’ values in the curriculum, as well as the importance of addressing real-life relationship challenges and practical applications within the curriculum. Only one couple transitioning to parenthood has enrolled in the program and data is currently being collected.
Embargo
Stance detection enhanced by large language models
(2025) Gyawali, Nikesh
Stance detection, a subfield of opinion mining, is an important task in Natural Language Processing (NLP) that involves determining the attitude or position expressed by an author of a text towards a particular topic or claim, generally referred to as target. More specifically, the task involves automatically determining if an author of a text is In-Favor (Positive), Against (Negative), or Neutral towards a given target. Accurate stance detection is crucial for understanding complex social issues, guiding policy decisions, and shaping effective interventions. While the field of NLP has seen significant progress, capturing nuanced stances from diverse and often ambiguous data remains a challenge. Recent developments in Large Language Models (LLMs) have transformed the field by offering unprecedented capabilities in interpreting subtle linguistic cues and context-dependent meanings. This dissertation advances the field of stance detection by utilizing Large Language Models (LLMs) to improve methodologies across multiple critical and socially impactful domains. In this dissertation, we first explore LLM-enhanced approaches to stance detection in the socially controversial and polarizing topics of gun regulation and vaccines. We introduce the GunStance dataset, consisting of social media posts from X (formerly Twitter) posted by X users after major mass shooting events in the United States. By integrating labeled and unlabeled posts, this dataset allows comprehensive exploration of a semi-supervised learning framework in the context of stance detection. We propose a novel hybrid model that combines semi-supervised techniques with LLMs and show that our approach significantly outperforms traditional stance detection approaches. Furthermore, we assemble a large dataset of social media posts from X, capturing the vaccine discourse over a decade. The dataset includes seven years before COVID-19, as well as three COVID-19 years. Leveraging LLMs, social cognition theories and emotional dynamics, we analyze the vaccine dataset to capture the evolving public attitudes towards vaccines before and during the COVID-19 pandemic. Our study reveals increasing polarization and heightened emotional engagement, with a notable rise in vaccine skepticism amid the global health crisis. Expanding into the less controversial but important financial domain, we construct a financial stance detection corpus from annual 10-K reports filed to U.S. Securities and Exchange Commission (SEC) and earnings call transcripts (ECT) by extracting short text fragments relevant to key financial metrics, such as debt, earnings per share (EPS), and sales, and annotating them using LLM-driven methodologies with strict human validation. This financial stance detection corpus facilitates extensive evaluation of LLMs' ability to detect subtle stances towards financial metrics, a task that requires complex reasoning. Our findings demonstrate the effectiveness of LLMs in performing accurate stance detection without extensive labeled data, showcasing their potential for real-world financial analysis applications. Building upon these insights, we also introduce the Modular Prompt Optimization for Stance Detection (MoPrO-SD) framework. This framework utilizes the prompt optimization capabilities of LLMs by breaking down the complex stance detection prompt into modular, optimizable components. Each module is iteratively refined using LLMs as prompt optimizers, leading to an improved prompt that outperforms human-crafted prompts on several stance detection benchmarks. Collectively, this dissertation advances the field of stance detection by providing comprehensive evidence on the use of LLMs to enhance the performance, adaptability, and efficiency of stance detection methodologies across social media posts and financial documents, offering an analytical and scalable framework for informed and nuanced decision-making in an increasingly digital and interconnected world.
Embargo
From grassroots to mainstream: A structural actor-network study of organizational growth and political influence
(2025) McCarthy, Adrienne
Students have long played an important role in U.S. political activism. While research has investigated the historical relevance of campus activist groups in the U.S., little research has focused on the mechanisms through which such groups curate influence and impact in the contemporary age. This dissertation utilizes a “structural” Actor-Network Theory (ANT) approach to trace the network of prominent grassroots organization to powerful organizations and figures, embedding themselves firmly in the contemporary political landscape. This vast network provides empirical evidence to support prior literature on grassroots political organizations, demonstrates the capacity for an application of structural ANT, and highlights the impact that a relatively small but organized configuration of individuals and groups can have on modern American politics.
Open Access
Climate-crop interactions in the U.S. winter wheat belt
(2025) Zhang, Lina
Climate change poses severe challenges to global food security. Wheat is one of staple food crops worldwide, and its production faces mounting pressures from rising food demand due to quick increase in world population. Furthermore, increasing exposure to climate extremes, such as heat and drought, during sensitive growth stages can cause abrupt yield shocks, threatening its production sustainability. However, the mechanisms underlying climate-crop interactions remain poorly understood despite decades of research. The U.S. Great Plains is the nation’s primary hard winter wheat belt and breadbasket. Recent rapid changes in temperature and precipitation during wheat development have significantly affected wheat production in the region. To address these issues, we investigated how drought shocks, breeding progress, and phenological shifts have collectively shaped winter wheat resilience under historical climate change in the region. By analyzing long-term surface climate data from dryland wheat-growing regions at both county- and site levels using statistical and machine-learning approaches, we showed that the unprecedented 2022-2023 drought reduced U.S. hard winter wheat production by 37% through both yield reduction and crop abandonment, driving Dust Bowl-like impacts. Random forest and game-theoretic analyses revealed that spring drought primarily drove yield reduction, whereas fall drought dominated crop abandonment. Moreover, the La Niña phase of the El Niño-Southern Oscillation (ENSO) significantly increased abandonment rates compared to El Niño, underscoring the need to jointly address yield decline and abandonment to stabilize production under climate extremes. Analyzing cultivar-specific data from 1982 to 2020, we found that compound hot-dry (HD) events during the grain filling period reduced yields by an average of 6%, whereas breeding-driven yield gains were accompanied by reduced HD resilience: newer cultivars exhibited greater yield potential but increased sensitivity to HD stress. These findings revealed a trade-off between productivity and resilience, pointing to the urgent need to reorient breeding strategies toward increasing abiotic stress tolerance. To investigate the long-term climate trend impacts on yield, we accounted for climate-driven shifts in phenology, often overlooked in previous studies, by tracking the same cultivar cultivated in the same fields across decades. We approximated this experiment using the constant check cultivar ‘Kharkof,’ cultivated for 65 years (1960-2024) across the Great Plains, and demonstrated that long-term warming advanced phenological stages and extended the reproductive window (double ridge-heading), partially offsetting the negative impacts of heat stress. Warming also reduced cold injury in high-latitude regions, contributing to yield gains. In contrast, the fixed-season assumption overestimated the negative impacts of climate trends by nearly threefold, largely because it exaggerated the negative effects of rising temperatures. Those findings highlight the critical role of phenological shifts in modulating climate impacts on crop yields and provide a more nuanced understanding on how historical climate trends have shaped crop yields. This work provides a more nuanced view of climate-crop interactions and identifies adaptation pathways, which may benefit development of climate-informed policy for improvement of wheat breeding strategy and abiotic stress management.
Open Access
The development of bio-based adhesives for the manufacture of structural-use engineered wood products
(2025) Harris, Laurelyn
The increasing demand for sustainable construction has intensified research into bio-based adhesives for engineered wood products (EWPs), aiming to reduce the environmental and health impacts associated with conventional synthetic-based adhesives. Synthetic adhesives such as phenol-formaldehyde, resorcinol-formaldehyde, and polyurethane provide high strength and durability but emit volatile organic compounds (VOCs) and formaldehyde, contributing to poor indoor air quality and hindering end-of-life recyclability. To support green building initiatives and circular economic goals, this report compiles, evaluates, and compares research on lignin-based and soy protein-based bio-adhesives to determine their suitability for structural and exterior applications in EWPs. This report provides a comprehensive review of existing studies to identify formulation methods, material sources, chemical properties, and performance outcomes of lignin-based and soy protein-based adhesives. Lignin adhesives utilize biorefinery by-products and bio-reactants such as glyoxal to replace petroleum-derived phenol and formaldehyde, while soy protein adhesives, derived from defatted soy flour or soy protein isolate, eliminate formaldehyde and can be modified to improve bond strength and water resistance. The report organizes and synthesizes this information into comparative tables and figures summarizing mechanical performance metrics, such as shear strength, modulus of elasticity, and moisture resistance, under various test conditions. The findings of this report demonstrate that both lignin and soy-protein-based adhesives show strong potential to meet or approach the performance of current synthetic adhesives while offering significant environmental and health benefits. However, limitations remain in water resistance, curing time, and large-scale manufacturing feasibility. The report serves as a consolidated reference for researchers and industry professionals seeking to advance the application of bio-adhesives in structural-use EWPs. By presenting a clear comparison of formulation strategies, performance outcomes, and areas for continued development, this report contributes to the progression of safer, recyclable, and low-emission building materials essential to achieving long-term sustainability in the construction industry.
Embargo
A structural basis for bacterial evasion of antibody responses through inhibitory receptor targeting
(2025) Ying, Zhang
Group B Streptococcus (GBS; Streptococcus agalactiae) continues to be a primary cause of neonatal sepsis while also representing a significant pathogen among immunocompromised adults. This work reveals the structural basis behind a new GBS immune-evasion mechanism whereby the cell-wall–anchored β protein (~130 kDa) interacts with human inhibitory receptors to diminish antibody-mediated effector responses. The β protein functions as a ligand for leukocyte immunoglobulin-like receptor B3 (LILRB3) an ITIM-containing inhibitory receptor found on human myeloid cells that dampens Fc receptor–driven activation. Our observations provide a framework for defining the molecular-level details underpinning the β-LILRB3 interaction and using this information to probe its functional consequences. Domain mapping combined with surface plasmon resonance experiments uncovered two separate regions within the β protein B6C (residues 226-391) and B75KN (residues 504-789) that serve as independent LILRB3-binding domains, with both displaying nanomolar binding affinities. The B6C crystal structure, resolved to 2.05 Å, unveiled an extended four-helix bundle configuration spanning ~111 Å, which differed substantially from existing computational models. Solution structures of both B6C/LILRB3 and B75KN-CTD/LILRB3 complexes were characterized using small-angle X-ray scattering with size-exclusion chromatography (SEC-SAXS), demonstrating that each domain recognizes the D3-D4 region of LILRB3. Mutagenesis experiments based on structural insights pinpointed essential interface residues: K332 and R336 within B6C, along with L721, D722, and F740 in B75KN-CTD. These mutations selectively eliminated LILRB3 binding yet maintained interactions with additional host proteins such as complement Factor H. Analysis of the ternary complex via SEC-SAXS showed that individual β protein molecules engage two LILRB3 ectodomains concurrently, establishing a 1:2 stoichiometry that facilitates receptor cross-linking. Investigation of biological consequences demonstrated that β protein-induced LILRB3 clustering inhibits antibody-mediated neutrophil activation and bacterial killing, thereby promoting bacterial persistence. This mechanism exhibits species specificity, as the β protein cannot bind the murine ortholog PIR-B. Additionally, naturally existing LILRB3 variants within the D3-D4 domain entirely abolished β protein recognition, indicating that host genetic diversity could modulate GBS infection outcomes. In summary, we provide the initial structural descriptions of a mechanism used by a prominent bacterial pathogen to exploit human inhibitory receptors and thereby overcome antibody-based immunity. Uncovering this new virulence mechanism advances our comprehension of GBS pathogenesis and offers potential avenues for innovative therapeutic strategies. It also provides a rationale for investigating similar evasion mechanisms in diverse host/pathogen interactions.

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