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Item Fatigue-based posture and motion predictions(2024-07) Barman, ShuvrodebThis dissertation presents two predictive biomechanics studies, fatigue-based posture and motion predictions. For the fatigue-based posture prediction study, the three-compartment controller fatigue model is integrated with an inverse dynamics optimization routine to predict the optimal posture, joint fatigue, and endurance time for a box carrying task. A two-dimensional human model with 10 degrees of freedom is used. For the box carrying task, the feet are stationary on the ground, and the hand location and box weight are given. The joint fatigue-based posture prediction formulation considers joint angles, three-compartment control values, and total box carrying duration (endurance time) as design variables. The objective is to maximize the total time while adhering to task and fatigue constraints, including compartment unity constraint, residual capacity constraint, and a novel coupled failure constraint. The optimization predicts the optimal posture, joint torque, endurance time, joint fatigue progression, and joint failure conditions. The novel joint fatigue-based formulation suggests the optimal posture to maximize endurance time with a given box weight. The simulation is efficient and provides optimal results in about 5 seconds of CPU time on a regular computer. The fatigue-based motion prediction study investigates the progression of fatigue and forecasts the optimal motion trajectory in a repetitive lifting task. The lifting problem is mathematically formulated as an optimization problem to minimize dynamic effort and joint acceleration subject to physical and task-specific constraints. The design variables include control points that determine joint angle profiles using quartic B-splines. Additionally, profiles of the dimensions of the three and four compartments for spinal, shoulder, elbow, hip, and knee joints are treated as additional design variables. The study involves numerical simulations and experiments, using a 20 kg box as an external load for repetitive lifting. Simulation outcomes include detailed joint angle profiles, joint torques, and the progression of joint fatigue. The profiles of joint angles and torques follow distinct periodic patterns. Simulation results suggest a maximum of 11 (3CC) and 13 (4CCr) lifting cycles before the repetitive lifting task with a 20 kg box becomes unfeasible. Notably, these projected outcomes match observations from the experiments (predicted 13 cycles). Fatigue-based posture and motion predictions have significant contributions for ergonomic design and injury prevention in workplace.Item Directional fire patterns formed by convection currents in the upper layer of a compartment fire(2024-07) Ayres, Paul F.Fire pattern recognition and identification is a fundamental part of fire investigations. In order to avoid unintentional bias, the interpretation of fire patterns should be validated, and their limitations known. This study introduces a fire pattern that has been observed at real-world fire scenes, but not yet documented in fire investigation treatises. The fire pattern had been observed on objects that protrude into the upper layer of a compartment fire. This mixed-methods study consisted of physical experiments, computational fluid dynamics models, and statistical analysis, which were designed to replicate these types of patterns, identify its characteristics, validate its interpretation, and acknowledge its limitations. These directional fire patterns, described as “turbulent flow patterns,” were found to be good indicators of the direction that the products of combustion came from, provided that they are not in an area that an eddy is be expected to form. The study also verifies the presence of convection currents in the upper layer of a compartment fire that are independent of the dominant flow path. The information presented in this study is relevant to fire/arson investigators who use fire patterns to determine the area of origin of a fire. The conclusion section of this study provides recommended practices for fire investigators to identify, assess, document, and interpret turbulent flow patterns.Item When stories do not matter: An examination of legitimate distinctiveness in pooling equilibria(2024-07) Arteaga-Fonseca, JorgeIf investors cannot perceive differences among ventures, how can they decide which ventures to support? By marrying signaling theory with the legitimate distinctiveness literature, I argue that a pooling equilibrium—a context wherein investors cannot discriminate higher quality signalers from lower quality signalers due to unreliable signals—will limit the benefits of differentiation (e.g., an innovation that differentiates from peers) as a resource acquisition strategy. In this regard, I argue that the type of equilibrium present will moderate the relationship between legitimate distinctiveness and access to resources. Following the legitimate distinctiveness literature, I theorize that the benefits of legitimate distinctiveness depend on the possibility of actually being able to establish perceptions of both conformity and distinctiveness in the minds of audiences. That is, if an environment is such that audience members cannot perceive one or both properties, legitimate distinctiveness cannot be established, and benefits may not be forthcoming. Thus, I argue that the benefits accrued from legitimate distinctiveness to increase access to resources will hold in a separating equilibrium; but in a pooling equilibrium different dynamics may be at play. I, thus, theorize that the presence of a pooling equilibrium limits the effect of legitimate distinctiveness on private equity funding because investors cannot perceive differentiation signals to discriminate higher quality ventures from lower quality ventures. This dissertation contributes to signaling and entrepreneurship literature by being one of the first studies to explore a pooling equilibrium in the entrepreneurial process. This dissertation also relieves the tension in the conformity versus distinctiveness paradox, by suggesting that the signaling context significantly influences this decision for entrepreneurs, contributing to the integration of institutional theory and strategic management. I find support for my theorizing. In particular, the positive effect of distinctiveness and conformity on increased access to resources when assuming the existence of a separating equilibria. In a pooling equilibrium, though, the positive relationship between conformity and access to resources is supported, while post hoc analysis reveals the negative relationship between distinctiveness and access to resources.Item Advancing transboundary water resources assessment, monitoring and modeling using grace, machine-learning, and land-hydro models(2024-07) Arshad, ArfanThe Indus Basin is facing water scarcity intensified by a drier climate and growing water demands for irrigation and population consumption. Ensuring environmental sustainability and resilience in the Indus Cascade necessitates a comprehensive understanding of human activities and climate influences on terrestrial water storage and groundwater depletion. The primary goal of this research is to promote food and water security in Indus Basin by providing place-based water management solutions. To do so, we used GRACE data, spatial downscaling, hydrological and land surface modeling and machine learning tools to advance the predictability of water resources across time and space. Results indicated that spatial downscaling of GRACE data to 1km resolution largely improved the groundwater storage estimations when compared with the groundwater monitoring data. All twenty sub-regions in the Indus Basin indicated irreversible decline in terrestrial water storage (TWS) and groundwater storage (GWS) between 2002 and 2023. However, the declining rate was dominant in the downstream areas where human activities are major influencing factors. By employing machine learning models, we reconstructed high-resolution (1km) data of groundwater level, enabling better monitoring and understanding of groundwater changes and facilitating more accurate groundwater management in these regions. By combining downscaled GRACE data with SWAT hydrological fluxes in spatial water balance, we also seek to improve groundwater depletion estimations in 55 canal command areas for understanding impacts of different cropping systems, growing food productions and unequal distributions of surface water. The significance of PhD dissertation research is amplified by the generation of high-resolution terrestrial water storage dynamics, precipitation, water table, and groundwater depletion datasets in data-sparse areas across transboundary Basin, which we made publicly available on platforms such as Figshare, enabling researchers and policymakers to access valuable information for informed decision-making. The methodologies and programming tools developed during this research are applicable globally, offering solutions to regions grappling with environmental challenges.Item Ultramicrotomy and infrared imaging applied to the forensic examination of automotive paint(2024-07) Zhong, HaoranIn the forensic examination of automotive paint, each layer of paint is analyzed individually by infrared (IR) spectroscopy. Laboratories in North America typically hand section each layer and present each separated layer to an IR spectrometer for analysis, which is time consuming. In addition, sampling too close to the boundary between adjacent layers can pose a problem as it produces an IR spectrum that is a mixture of two layers. Not having a “pure” IR spectrum of each layer will prevent a meaningful comparison between each paint layer or in the situation of searching an automotive database will prevent the forensic paint examiner from developing an accurate hit list of potential suspects. These two problems have been addressed by collecting concatenated IR data from all paint layers in a single analysis by interrogating the cross sectioned layers of the paint sample using Fourier transform infrared (FTIR) imaging microscopy. Using an ultramicrotome instead of a conventional microtome allows for so-called “small” paint chips which are often found on the clothing of a pedestrian in a hit-and-run to be cross sectioned and analyzed than what is practical by conventional FTIR. Decatenation of the concatenated IR data is achieved by multivariate curve resolution using alternating least squares (ALS) or modified alternating least squares (MALS) to obtain an IR spectrum of each automotive paint layer. A new baseline correction algorithm that integrates three well known baseline correction methods developed a snapshot of the background and minimized error in the MALS recovered spectra. In addition, limiting the FTIR spectrum of each layer to the region corresponding to the binder is shown to be sufficient to identify the assembly plant of the automotive vehicle and perform accurate library searches to identify the vehicle manufacturer, line, and model of the vehicle from which the original equipment manufacturer paint chip originated.Item Brand activism, the role of moral grandstanding(2024-07) Zaboli, SahelBig brands and companies understand the increasing importance of social issues, and people want to see their favorite brands care about and take a stand on social issues (Schumann, Hathcote, & West, 1991)However, when brands are active in the socio-political domain, their underlying motivations are increasingly examined by consumers (Holt, 2002). Signaling morality and one’s moral status may not always be received well by others, it could lead to Moral Grandstanding Perception which is using public moral discourse to achieve social status(Cramwinckel, van den Bos, & van Dijk, 2015; Tosi & Warmke, 2016). This research, using experimental method, proposes that when brand advocates for a social or political issue, they run the risk of engaging in moral grandstanding (MG) which can help explain the relationship between consumers’ adverse reactions to brand activism by showing that consumers perceive a brand’s moral stance not as sincere support but as a gesture for showing off.Item Beyond burnout: A naturalistic inquiry of elementary teachers' experiences(2024-07) Wilkins, Amber NicoleThis naturalistic inquiry takes a deep dive into the experiences of elementary classroom teachers who have experienced feelings of burnout in their career and persevered, choosing to stay in the classroom, overcoming those feelings. Using Maslow’s Hierarchy of Needs as a theoretical lens, the researcher studied the teachers in their school setting.Item Phase field modeling of anisotropic grain growth using a Spherical-Gaussian-based 5-D computational approach(2024-07) Yeo, Lenissongui CedricStudies have shown that specific grain boundaries (GBs) greatly influence the properties of materials, indicating that material performance can be enhanced through deliberate GB engineering. Twin boundaries, for instance, have been found to significantly improve properties like corrosion resistance and electrical conductivity. Given that GBs exhibit five degrees of freedom for anisotropy and that current methods to incorporate both misorientation and inclination dependencies are either insufficient or complex to implement, there is a need for further research and advanced modeling techniques. In this study, a previously developed Spherical-Gaussian method is employed to incorporate 5-D anisotropy in two phase field models, originally developed by Moelans, referred to as the epsilon and gamma models. Orientations are assigned to individual grains using quaternions, which are then used to compute quaternion misorientations at each GB, driving ongoing mesoscale changes. To account for specific low-energy boundaries, such as twin boundaries, local minima or specific grain boundaries are stored in a minima library and used in the phase field models through a developed gaussian switch. The 2-D gaussian switches compare the system’s misorientations between pairs of grains to the list of minima misorientations, inducing a spherical-Gaussian effect that adjusts the GB energy to the desired value from a pre-specified base GB energy. This method allows GB energy to change dynamically as the GB plane and grain misorientations evolve. Simulations are performed using the Multiphysics Object-Oriented Simulation Environment (MOOSE) with both models. Results from bicrystal simulations across six different cases showed that the models could accurately reproduce validated GB energy, irrespective of initial conditions, as long as a library misorientation is recognized. Complex phenomena, such as faceting due to two minima near the GB typically observed at the atomistic scale, were also observed at the mesoscale with the improved models. Additional tricrystal simulations demonstrated significant variation from the isotropic model when anisotropy was introduced through GB energy alone, with only slight deviation when adding anisotropy through GB mobility, a trend noted in prior studies. The effective application of these models presents numerous opportunities for designing superior materials for industrial use.Item Indian Removal and the Native nations of Northeast Oklahoma(2024-07) Yeakley, SheldonPresently, the Wyandotte, Myaamia, Shawnee, Eastern Shawnee, Modoc, Quapaw, Seneca-Cayuga, Peoria, and Odawa reside within a single Oklahoma county on the border of Missouri, Kansas, and Arkansas. Explaining how these nations, whose roots stretch across the North American continent, came to live within this small geographic area uncovers a large story– one which fundamentally reevaluates the scope and significance of American Indian Removal. Their repeated displacements occurred both well before and long after the passage of the 1830 Indian Removal Act. Importantly, this expansive period of Removal contained within its span previously separate historical topics from the War of 1812, the American Civil War, Reconstruction, Allotment, Termination, Reservations, to Boarding Schools. Beyond temporal adjustments, the narratives of these nine Nations offer a new geographical frame for Removal’s study. Decentering the Mississippi River as a boundary for Removal’s reach, this dissertation travels from California to Ohio, from Michigan to Arkansas detailing a story relevant to the entire country. Critically, beyond revising the perceived scope of Removal, this project argues for a revised vision of Removal’s significance. As Indigenous peoples and settlers moved across the country, more than their location changed. Caught within simultaneous and multifaceted diasporas, Removal served as a means of entanglement and national genesis. As the United States expelled Native peoples in hopes of constructing their own modern nation, they failed to eliminate Indigenous nationhood. Unexpectedly, Removal often served as a catalyst by which Native nations came together to form new confederacies, separate into independent nations, reconstituting themselves in new places. In each case, the U.S.’s effort to rid themselves of Native peoples produced new legal obligations which further entangled both settler and Native nations. While the saga of Indian Removal was not the origin of these Indigenous nations, it was a nation-building process; one of orogeny. As their location shifted, as the land underneath them moved, new structures emerged. Caught within a system of profound movement and destruction, these communities’ continued presence proves that Native nations were not eliminated by Removal but were profoundly changed by it. Through their survival of this genocidal moment, modern Native nations formed.Item Illness uncertainty trajectories among parents of children with atypical genital appearance due to differences of sex development(2024-07) Traino, Katherine A.Objective: The present study aimed to identify distinct trajectories of parental illness uncertainty appraisals among parents of children born with atypical genital appearance due to a Difference of Sex Development (DSD) over the first year following diagnosis. It was hypothesized that four trajectories would emerge, low stable, high stable, decreasing, and increasing profiles, and that key demographic, familial, and medical factors would predict these trajectories. Methods: Participants included 56 mothers and 43 fathers of 57 children born with moderate to severe genital atypia. Participants were recruited from eleven specialty clinics across the United States. Growth mixture modeling (GMM) approaches, controlling for parent dyad clustering, were conducted to examine profiles of illness uncertainty ratings over time. Results: A three-class GMM was identified as the best fitting model with freely estimated intercept variances. The three profiles were labeled as “Moderate Stable” (63.8%), “Low Stable” (20.9%), and “Recovering” (15.3%). Those in the Recovering class were less likely to have a Congenital Adrenal Hyperplasia diagnosis (versus other conditions) and may also be more likely to report higher anxious symptoms at baseline. Conclusions: Findings highlight the nature of parents’ perceptions of ambiguity and uncertainty about their child’s diagnosis and treatment shortly following their child’s birth. Future research is needed to better understand how these trajectories might shift over the course of the child’s development. Tailored, evidence-based interventions are needed to support families coping with uncertainty while raising a child with chronic health needs and bolster long-term family functioning.Item From shame to empowerment: A fat liberation journey(2024-07) Ward, Melissa LinWeight stigma and discrimination occur in various environments, such as in educational, medical, and occupational settings, as well as in the contexts of interpersonal relationships (i.e. Pulh & Brownell, 2006). Experiences of weight stigma and discrimination often harm fat people’s mental well-being (i.e. Wu & Berry, 2018) and relational functioning (Lewis et al., 2011), which makes it an important area of concern for researchers and practitioners in psychology, especially as psychologists are being called more often to adopt a liberation based mindset when conceptualizing and treating mental health concerns in people with marginalized identities (Singh, 2020). Because relational cultural theory (RCT) focuses on relationships and culture in understanding human development and mental health, it is an ideal theory for providing a framework for conceptualizing the harm done by weight-based oppression, as well as considering how fat people can cope and heal from these experiences. Additionally, given the empowering nature of fat positive and fat liberationist spaces (Dickins et al., 2011; Dickins et al., 2016; Lewis et al., 2010), exploring the impact of a fat person’s fat positive and liberationist identity, using RCT, may also yield important insights into how fat positive and fat liberationist fat people cope with and heal from experiences of weight-based oppression. Thus, to gain a deeper understanding of these variables, 9 participants who identified as both fat and either fat positive or fat liberationist were interviewed about how they came to this identity and the impact that it has had on them. Once the data was collected, the participants’ narratives were analyzed using narrative analysis. The results support past research findings that experiences of weight stigma and discrimination have a devastating impact on fat people. The findings also suggest participants' journey toward a fat liberation was often slow and involved many factors. Lastly, while all participants identified challenges in their life since this identity developed, such as tension in relationships due to anti-fat views, the participants reported their fat positive or fat liberationist identity has had an overwhelmingly positive impact on their view of themselves and engagement in relationships.Item "You are hope made flesh": Gender and sexuality in Indigenous Oklahoma(2024-07) Waters, Savannah J.The history of Indigenous understandings of gender and sexuality are complex and multifaceted. My research mines this cave of complexity in hopes to understand two-spirit life and its connections to the past ancestors and future kin. At the core, this writing asserts that modern two-spirit Indigenous people are a continuation and transformation of practices and identity of their past predecessors. Just like the discipline of history, two-spirit continuities are also accompanied by change. Ultimately, the two-spirit people are variation of each other only separated by time. The history of two-spirit people is extremely intricate and contains multiple truths. Using Muscogee methodologies, this research uses the state of Oklahoma as a way to investigate two-spirit life. The temporal scopes range from the 1800s to 2024. Many past histories on the topic offer a national approach to two-spirit history. While no doubt important, a larger national scope misses the very real, on-the-ground, experiences of Indigenous two-spirit people. The records concerning two-spirit people presented a challenged as narratives reveal multiple gaps. This dissertation seeks to expand knowledge of the two-spirit world by finding tangible topics in which to survey including religion, gender, sexuality, legal systems, politics, Oklahoma history, migration, community, and oral histories. These themes work together to form a story about some of the two-spirit people. Engaging with Native American and Indigenous Studies methodologies, my own person is written into the history to show how my life intertwined with my own research project. The inclusion of myself may help others to think about their own lives and experiences. Readers may realize they are not alone. The whole project is a loving study made for my family and community. Mvto (thank you!)Item Bayesian modeling and prediction for the time-to-terminal-event with unaligned longitudinal observations in electronic health records(2024-07) An, SiyuDiabetic Retinopathy (DR) is a prevalent complication among diabetic patients and early detection of DR is crucial in order to prevent vision loss. It is important to predict patients' survival time to the event of DR based on longitudinal observations of certain biomarkers. Such long-term predictions can be used to assess the risk of developing DR in the future. Utilizing electronic health records (EHR) gathered during patients' routine clinical visits, we are able to develop survival models using longitudinal lab measurements. Though the joint modeling of failure time data and longitudinal data have been extensively studied in the literature, existing approaches rarely concern about the unaligned nature of EHR observations. The alignment of longitudinal observations in time is crucial to specify a correct model and hence can significantly impact the ultimate estimation and inference. The mishandling of alignment will cause severe bias and often incorrect results. It is more challenging when the majority of patients are censored, i.e. without a terminal event. To address the challenges that arise from EHR or other type of observational studies, we propose a joint model based on shared random processes with time-reversed longitudinal processes. There are few capable existing literature on the estimation of each individual's curve in the joint modeling, which can be essential for personalized predictions. Regarding this issue, we consider nonparametric Gaussian processes (GP) for those individual curves. This dissertation proposes a Bayesian joint model with nonparametric GP priors for curves and posterior distributions are used for statistical inference. For Bayesian computations, we derive the Gibbs sampling for posterior inference as well as a Riemann manifold Hamiltonian Monte Carlo (RMHMC) technique for sampling non-Gaussian random curves in the posterior. With the fitted model, we further propose a marginal likelihood approach for predicting a patient's time to the terminal event given their longitudinal history. Simulation studies show that our approach can provide reasonable parameter estimation and is superior than other alignment approaches. Finally, we apply our model to a real EHR dataset for estimating and predicting DR survival times.Item Deep learning for fast quality assessment(2024-07) Taye, Mesfin B.This report presents an automated system for classifying the quality of Focused Assessment with Sonography for Trauma (FAST) ultrasound exams. Our dataset consisted of 441 FAST exams with 3,161 videos, graded from 1 (poor quality) to 5 (good quality). We deemed exams rated as 1 or 2 as poor quality, and those rated 3 to 5 as good quality. Our approach involved assigning the quality label of the exam to each video and then to each frame within, as frames lacked individual labels. We utilized a custom CNN autoencoder for image compression, and then used the encoder for further classification. The classification of a video or an exam as poor quality was determined if at least half of its frames or videos, respectively, were assessed as such. The encoder-classifier model outperformed the transfer learning model, with our ensemble testing accuracy achieving 98% for video quality and 100% sensitivity and specificity at the exam level. The performance of our encoder-classifier network significantly surpassed traditional transfer learning methods, demonstrating its effectiveness in accurately assessing ultrasound exam quality. Deep learning methods have shown remarkable efficacy in the domain of medical imaging, offering promising advancements for various diagnostic procedures. Nonetheless, a significant barrier to their widespread adoption is the opacity of their decision- making processes. Several techniques exist to explain model decisions; some focus on patterns specific to individual predictions, while others are interested in the overall pattern or logic of the decision. In this paper, we present a new modification to existing local explainability techniques—DeepLIFT and Integrated Gradient. These modifications aim to enhance local explainability, providing clearer insights into the model’s decision-making process. Furthermore, we introduce the Self-Organizing Map (SOM) as a novel approach to global explainability. This technique provides a global- level understanding by revealing patterns and trends in how deep learning models make classification decisions across a broad dataset. We combined these two new methods and applied them in a Focused Assessment with Sonography in trauma exam classification problem. Through our comprehensive analysis using local and global explainability techniques, we discovered that the clarity (sharpness) and informational content (density) of FAST ultrasound frames are pivotal attributes leveraged by deep learning algorithms for quality classification. This insight not only enhances our understanding of the underlying mechanisms of these models but also opens new avenues for improving the accuracy and reliability of image classification problems.Item Influence of school-based agricultural education on positive youth development: A mixed methods approach(2024-07) Smith, Nathaniel AndrewTrauma is not a novel phenomenon within the world or society. Kilpatrick et al. (2013) postulated that most individuals will experience at least one traumatic event in their life. Possibly the more disturbing truth about trauma is it can occur throughout all stages of a person’s life, sometimes even before the person is born (Narayan et al., 2019). These adverse childhood experiences (ACEs; Felitti et al., 1998) are generated by exposure to trauma while younger than the age of eighteen and can have life-long effects to a person’s mental and physical health. Protective and compensatory experiences (PACEs) serve as the antidote for ACEs (Hays-Grudo & Morris, 2020). Additionally, positive youth development (PYD) seeks to build the internal assets of caring, character, competency, confidence, connection, and contribution in youth (Lerner et al., 2005). The purpose of this convergent parallel mixed methods study aimed to examine the influence of school-based agricultural education (SBAE) on Ferguson College of Agriculture students’ (FCoA) PYD, PACEs scores, and time spent in an SBAE program. Five research objectives guided the study. The population for this study was all students, graduate and undergraduate, enrolled within the FCoA at OSU during the 2023-2024 academic calendar year (N = 3,313). Two preexisting instruments (i.e., the Positive Youth Development Inventory and the Protective and Compensatory Experiences Inventory) were used for the quantitative data collection process. Semi-structured qualitative interviews were also conducted using an interview protocol generated based on the 6Cs of the PYD theory. It was concluded that SBAE programs served as a positive, nurturing environment for the development of all 6Cs of PYD in FCoA students, and support networks enhanced resilience of students in SBAE programs. Recommendations for practice and future research were made based on the conclusion drawn from the study and guided by a new conceptual model introduced in the study: A protective pedagogical model for school-based agricultural education.Item Autonomy, competence, and relatedness support for virtual charter school teachers: A case study(2024-07) Ross, BradleeThis qualitative case study explores teacher support and persistence in a large virtual charter school in the midwestern part of the United States. Using self-determination theory as a theoretical lens, this study examines how the psychological needs of autonomy, competence, and relatedness of teachers in a virtual charter school are supported or thwarted. Findings suggest that teachers’ needs for autonomy and competence can be satisfied in a virtual charter context, while relatedness is a more difficult need for virtual charter schools to meet. This study also provides support for the utility of self-determination theory as lens for the further exploration of teacher support and retention in virtual schooling.Item Three essays on consumer preferences for potting mix containing Eastern Redcedar biochar, bias in direct and indirect questioning, and dialectic valuation method for prediction(2024-07) Silwal, PratikshyaUnderstanding consumer preferences and accurately predicting their behavior are critical for effective marketing and product development. This dissertation explores three distinct yet interconnected areas to enhance this understanding. The first chapter examines consumers’ willingness to pay for potting mix containing Eastern Redcedar (ERC) biochar through an online survey. The study finds that limited information leads to a non-significant negative impact on willingness to pay (WTP), while presenting ERC biochar as environmentally friendly increases WTP by $0.618 per cubic foot of potting mix bag. Providing detailed environmental benefits of ERC biochar further increases WTP by $1.63 and $2.42 for mixes with 10% and 20% ERC biochar, respectively. These findings suggest that there is a substantial market potential of potting mix containing biochar. The second chapter explores investigates whether differences in responses between direct and indirect questioning are due to social desirability bias or perceived self-other differences. The study shows that while social desirability bias affects responses to normative attributes, non-normative attributes reflect perceived self-other differences. These results challenge the assumption that indirect questioning solely mitigates social desirability bias, emphasizing the need for researchers to carefully consider its implications for accurate behavioral predictions and reducing survey biases. The third chapter addresses challenges in online surveys by introducing a dialectic approach that combines assembling and disassembling approaches. he assembling approach starts with individual attribute values to estimate attribute-bundles, while disassembling infers individual values from attribute-bundles. Prediction accuracy, measured by mean squared error (MSE) in a holdout sample, shows that the dialectic approach outperforms the other two, providing better predictive accuracy and utility parameters at the individual level. This approach also effectively identifies inattentive respondents, highlighting its practical advantages in survey research.Item Describing the connections between professional development and career longevity of school-based agricultural education teachers: A nationwide study(2024-07) Sewell, Emily AnneProfessional development aims to offer strategic and continuous learning that advances individuals at various levels in their skills and competencies toward success and sustainability (Lin et al., 2011; Ragins et al., 2003). Dynamic and comprehensive professional development is needed to meet the current and future needs of teachers to build a strong teacher workforce (Moser & McKim, 2020; Myung et al., 2013). Effective teachers make critical impacts on their students across the educational spectrum (Eck et al., 2020; Gaskey, 2003; Stronge et al., 2011) This study’s purpose was to determine the impact of SBAE teacher professional development on programmatic and behavioral changes, human capital, and career tenure. The study was undergirded by the theory of planned behavior (Ajzen, 1991), the teacher human capital framework (Myung et al., 2013), and a conceptual framework for teacher professional development (Sancar et al., 2021). Further the study was supported by the development of a conceptual framework for developing SBAE teachers’ intentions to teach. The explanatory sequential mixed-methods research design guided this study. The population of interest was all SBAE teachers nationwide (N = 14,756; Smith et al., 2024), a census approach was the target for data collection in Phase I. Responses were received from 973 individuals in 47 states, resulting in a 6.7% response rate. Phase II was guided by a qualitative interview protocol; 15 interviews were conducted. Findings revealed teachers’ participation, engagement, preferences, and intentions to continue teaching SBAE. Significant differences in engagement were found between the local and state level opportunities. Significant differences were also found in perceived preparedness between traditional and alternatively certified teachers. Regarding longevity in the profession, 61.20% of the respondents in this study indicated they plan to teach school-based agricultural education for the rest of their career. Four themes and 11 subthemes were developed through Phase II depicting the experiences of SBAE teachers and factors influencing their longevity. Eight conclusions were developed along with recommendations for research and practice based on the findings.Item Body talk among transgender and gender expansive individuals(2024-07) Scaer, AudreyThe purpose of the present study is to explore aspects of body talk among transgender and gender expansive (TGE) individuals in relation to gender dysphoria, external triggers of gender dysphoria, body dissatisfaction, and disordered eating. Body talk refers to what people share with others about their body (Lin et al., 2021). No previous researchers have explored body talk among TGE individuals. In this study, 139 TGE individuals completed an online survey, including the Body Talk Scale (Lin et al., 2020), the Eating Disorder Examination Questionnaire (Fairburn & Bergin, 1994), the Utrecht Gender Dysphoria Scale – Gender Spectrum (McGuire et al., 2020), the Gender Dysphoria Triggers Scale (Goldbach & Knutson, 2021, and the Body Image Scale – Gender Spectrum (Eli Coleman Institute for Sexual and Gender Health, n.d.). Correlational and multiple regression analyses were utilized. More negative fat talk and less positive body talk were found to be related to and predictive of body dissatisfaction and disordered eating among TGE individuals. Implications for practice include exploring body talk experiences with TGE clients if they are struggling with body satisfaction or disordered eating. It is recommended that future researchers explore aspects of body talk in relation to other gender minority stressors and resiliency factors among TGE individuals.Item “But she was the real owner”: Cherokee women as slaveholders, 1800-1865(2024-07) Rogers, Kristina E.This dissertation works to uncover the experiences and slaveholding practices of Cherokee women between 1800 and 1865. Elite Cherokee women used slaveholding as an avenue of power in the nineteenth century, as the United States and some Cherokee men worked to limit their political and economic power. The Cherokee Nation centralized their political system in the early nineteenth century and modeled their government after the United States, with some differences. This change took political power away from matrilineal clans and Cherokee women and gave it to a small group of elite men in a centralized government. These slaveholding women melded together older Cherokee gender roles alongside aspects of Euro-American gender roles in how they practiced slavery. Building off the scholarship of historians who studied white women and Native American slaveholders, this dissertation further expands the conversation surrounding chattel slavery by adding previously unstudied group of slaveholders. A variety of archival sources are used in this project including governmental sources from both the Cherokee Nation and the United States, court records, and Christian missionary records and letters, and newspapers. Sources from Cherokee women used include letters and diaries. It also uses oral history interviews conducted in the 1930s of Cherokee freedpeople and Cherokee women slaveholders. The interactions between enslaved people and Indigenous people are critical to understanding this period in Cherokee history and are discussed in this project. Grounded in ethnohistory, this dissertation argues that Cherokee women played central roles in the adoption, growth, and maintenance of chattel slavery between 1800 and the end of the Civil War. They found additional sources of economic power through the forced enslavement of Afro-Cherokee people.