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Publication OPTIMIZING SPEED SINTERING PARAMETERS FOR YTTRIA-STABILIZED ZIRCONIA(2024-12-19) Alshahrani, Abdulaziz; Zhang, YuSintering zirconia-based ceramics is a time-consuming process that uses slow heating and cooling rates. To fulfill the requirement of chair-side production of zirconia, speed and high-speed sintering technologies have emerged. However, the impact of these recent technologies on the thermal (transient stresses), physical, optical, and mechanical properties of yttria-stabilized zirconia (YSZ) still needs to be investigated. Therefore, a total of 750 disc-shaped specimens were pressed from zirconia powder (Zpex series, Tosoh Corp., Japan). Density was measured using the Archimedes method; the phase contents were determined by XRD; translucency was evaluated by a spectrophotometer on a black and white background; flexural strength and fatigue resistance were assessed by the biaxial flexure method; and the microstructure was examined by SEM imaging. We observed that transient thermal stresses were developed during sintering as a result of thermal gradients due to the fast heating and cooling rates adopted by speed firing. Finite element analysis (FEA) was utilized to quantify the magnitude of transient thermal stress. These significant observations highlighted the importance of pre-sintering conditions, especially if the pre-sintered zirconia blocks and discs were intended for speed sintering. Further, our findings showed that the currently recommended speed and high-speed sintering protocols of YSZ resulted in incomplete densification due to the brief dwell time of 5–16 min compared to 120 min in conventional sintering. Subsequently, the entrapped pores resulted in light scattering and reduced optical translucency. Interestingly, residual pores did not affect the flexural strength. The speed sintering protocols for 3–5 mol% YSZ were optimized by proposing higher sintering temperatures, 1550°C and 1580°C, and longer dwelling times, 40 min and 60 min. As a result, SS-1 (1550°C/40 min) for 3YSZ, SS-3 (1580°C/40 min) for 4YSZ, and SS-4 (1580°C/60 min) for 5YSZ was the optimal speed sintering conditions for those compositions, which led to significantly lower properties than the current speed and high-speed sintered YSZ and comparable to the gold standard “conventional sintering.” Finally, we demonstrated that the selected optimal speed sintering protocol for 5YSZ is more fatigue-resistant and exhibits better long-term mechanical stability.Publication So She May Thrive: Psychological Flexibility As A Pathway To Flourishing For Teenage Girls(2019-08-01) Christy Curtis Peterson; Yaden, DavidAdolescence is a heightened period of storm and stress due to the many developmental changes taking place during the teen years. For teenage girls, these challenges are often exacerbated by environmental stressors including impossible cultural standards of success, media overuse, and daily harassment by peers that threaten overall well-being. This capstone reviews research in positive psychology that promises to improve teenage girls’ ability to navigate life stressors, and to embrace adolescence as a time of wonder—of curiosity and exploration, passion, novelty-seeking and building new relationships. Psychological flexibility is proposed as a cornerstone of adolescent health and well-being, and its presence may help girls navigate the challenges posed by the adolescent years with greater resilience, connection and courage. Psychological flexibility refers to the ability to connect to the present moment and to change or persist in behaviors that align with deeply held personal values (Hayes, Strosahl, & Wilson, 2012). Although a fluid construct, research suggests that emotion regulation flexibility, mindfulness, self-compassion, positivity, and valued action increase psychological flexibility and its many benefits. Targeted interventions including Mindful Self-Compassion and a modified Acceptance and Commitment Therapy training are discussed as promising strategies to help teenage girls cultivate psychological flexibility as they transition from girls into thriving adults.Publication The Adoption of Iron in Western Iran in the Early First Millennium B.C.: An Archaeometallurgical Study(1981) Pigott, Vincent Charles; Dyson, Jr., Robert H.Publication Understanding the Barriers faced by African American Licensed Clinical Social Workers (LCSWs) to Medicaid Network Provider Participation(2024-05-18) Smith, Cassandra Denise; Bachman, SaraUNDERSTANDING THE BARRIERS FACED BY AFRICAN AMERICAN LICENSED CLINICAL SOCIAL WORKERS TO MEDICAID NETWORK PROVIDER PARTICIPATION Cassandra D. Smith, MSW, LCSW-BACS Committee: Sara S. Bachman, PhD and Tamara Cadet, PhD LICSW MPH Purpose: African Americans’ mental illness is more untreated than that of white Americans (Snowden, 2012). Studies also show that African Americans are more likely than white Americans to develop chronic mental illness (Snowden, 2012) and compared to their white counterparts, African Americans are more likely to be misdiagnosed (Office of the Surgeon General et al., 2001). Results from studies show that African Americans prefer African American providers, have more positive perceptions of African American providers, and that racial congruence does positively impact treatment outcomes for this population (Cabral & Smith, 2011). Ensuring a racially and ethnically diverse Medicaid provider network can impact those treatment outcomes for Medicaid consumers. This study aims to identify and understand the barriers faced by African American (AA) Licensed Clinical Social Workers (LCSW) to Medicaid Network Provider Participation. Methods: Data collected via an online survey was analyzed using descriptive statistics. Means, standard deviations, and range of scores were calculated for all continuous variables including age and number of years as an LCSW in Louisiana. Frequencies were summarized for all categorical variables including race; work status; practice setting; Medicaid provider (yes/no); reasons for not accepting Medicaid; MCO credentialing agencies; reasons for non-accreditation; level of satisfaction with Medicaid payment rates; level of satisfaction with the contracting and credentialing process; level of satisfaction with regulations, oversight and administrative burden associated with being a Medicaid provider; most impactful consideration in decision to become a Medicaid provider; level of difficulty in obtaining a $50,000 line of credit for credentialing; and level of difficulty in obtaining National Accreditation. Each variable was also separated by race (Black or AA and White) to provide context using cross tabulation tables. 5 Semi structured interviews were conducted as a qualitative pilot with original coding in categories aligned with the quantitative variables. Results: A total of N=128 social workers participated in the study. The sample as a whole ranged in their experience as Licensed Clinical Social Workers (LCSW) from 0-54 years, with an average of 19 years (SD=14). Overall, respondents ranged in age from 22-87, with an average age of 52 (SD=14). 60% of AA respondents reported that they do provide Behavioral Health services to Medicaid clients. AA respondents largest reported reason for this outside of not working for an agency that provided Medicaid service was “I do not have the capacity or resources to do so (time, finances, knowledge, etc.)” at 23%. The second largest reported reason amongst this demographic at 15% was “Medicaid reimbursement was too low”. Other reasons reported were non system related responses related to work setting or position. 83% of AA respondents reported being “Dissatisfied to Very Dissatisfied’ with Medicaid Reimbursement rates, 55% of AA respondents reported being “Dissatisfied to Very Dissatisfied” with the Contracting and Credentialing Process and 72% of AA respondents reported being “Dissatisfied to Very Dissatisfied” with the Regulations, Oversight, and Administrative Burden, etc.) Solutions for barriers identified through the literature and through pilot qualitative interviews included amendment of regulation to remove the requirement for additional licensure, alternative payment methods, identification of alternatives to National Accreditation; MCOs providing provider grants, as well as administrative support through technology and centralized billing platforms, and the creation of an ombudsman to address ongoing provider issues are other possible solutions. Additional solutions offered were streamlining of the billing and authorization processes to create uniformity across MCOs in the state. African American LCSWs also believe that additional local staff should be hired by MCOs to address provider concerns. Lastly, of course, raising reimbursement rates for Medicaid Behavioral health services was a central theme in the data. Conclusions: This study’s data on barriers AA LCSWs have to Medicaid Provider Network participation provides valuable information to guide regulatory policy and to develop strategies for implementing interventions to build the capacity of AA social workers. Improving Medicaid reimbursement rates, addressing concerns with contracting and credentialing, as well as concerns with regulatory requirements can help to increase the number of AA LCSWs in the Medicaid Provider Network. Recommended areas for further study include examining the potential disproportional impact these barriers may have on AA providers and implementation study of the effectiveness of capacity building interventions targeting AA LCSWs who desire to provide Medicaid services. Additionally, future research examining the possible connection between AA LCSWs access to capital and their ability to meet quality standards should also be considered. Lastly, comparing AA LCSW experiences in the workforce and in Medicaid networks across states could provide valuable knowledge.Publication Shape Recovery and Segmentation with Deformable Part Models(1987) Solina, Franc; Bajcsy, RuzenaA method for recovery of compact volumetric models for shape representation and segmentation in computer vision is introduced. The models are superquadrics with parametric deformations (bending, tapering, and cavity deformation). The input for the model recovery is three-dimensional range points. We define an energy or cost function whose value depends on the distance of points from the model's surface and on the overall size of the model. Model recovery is formulated as a least-squares minimization of the cost function for all range points belonging to a single part. The initial estimate required for minimization is the rough position, orientation and size of the object. During the iterative gradient descent minimization process, all model parameters are adjusted simultaneously, recovering position, orientation, size and shape of the model, such that most of the given range points lie close to the model's surface. Because of the ambiguity of superquadric models, the same shape can be described with different sets of parameters. A specific solution among several acceptable solutions, which are all minima in the parameter space, can be reached by constraining the search to a part of the parameter space. The many shallow local minima in the parameter space are avoided as a solution by using a stochastic technique during minimization. Segmentation is defined as a description of objects or scenes in terms of the adopted shape vocabulary. Model recovery of an object consisting of several parts starts by computing the rough position, orientation and size of the whole object. By allowing a variable number of range points in a model, a model can actively search for a better fit (by compressing itself and expanding) resulting in a subdivision of the object into a model representing the largest part of the object and points belonging to the rest of the scene. Using the same method, the remaining points can be recursively subdivided into parts each represented with a single compact volumetric model. Results using real range data show that the recovered models are stable and that the recovery procedure is fast.