University of Tennessee Institute of Agriculture
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From Coping Strategies to Fan Well-Being: Resource Dynamics of Team Identification, Impulse Control, and Psychological Capital in Negative Experiences
No full textGuided by conservation of resources theory, the authors examine how team identification, impulse control difficulties, coping strategies, and psychological capital shape fans’ well-being in negative fan experiences. Survey from 300 sport fans were analyzed using structural equation modeling. Results showed that identification promoted adaptive coping and reduced cutting off reflected failure, whereas impulse control difficulties increased denial and cutting off reflected failure. Denial unexpectedly enhanced psychological capital while reducing well-being, and venting functioned as a double-edged mediator across positive/negative pathways. Psychological capital was the strongest predictor of well-being, underscoring its role as a central resource linking coping to outcomes
Evaluation of the Efficacy of SCSP Vaccine Against Streptococcus uberis Mastitis in Dairy Cows
No full textThis study evaluated the efficacy of the Staphylococcus chromogenes surface-associated proteins (SCSP) vaccine against experimentally induced Streptococcus uberis mastitis in dairy cows. Sixty healthy pregnant Holstein dairy cows were randomized into SCSP-vaccinated (n = 30) and unvaccinated control (n = 30) groups. Cows in the SCSP group were given two subcutaneous vaccinations of SCSP vaccine with Emulsigen-D adjuvant at drying off (D0) and 21 days after drying off (D+21), whereas cows in the control group were injected subcutaneously with phosphate buffered saline (PBS, pH 7.5) with Emulsigen-D at similar time points. Clinical observation of cows for mastitis and other diseases, body temperature, vaccine injection site reaction, bacteriological culture of mammary secretion, and serum antibody titers were monitored postvaccination. All cows in both groups were challenged with S. uberis strain UT888 by teat dip infection method for 14 consecutive days from D+35 to D+48. Clinical mastitis, bacteriological culture of mammary secretion/milk, somatic cell count, rectal body temperature and milk yield were monitored during challenge, after challenge before calving and for 30 days in milk postcalving. . The SCSP vaccine significantly reduced the incidence of clinical mastitis at the cow level (19.2%) in vaccinates compared to the control group (48%). Subclinical mastitis was also lower in vaccinates (30.8%) compared to the control group (48%), even though not statistically significant. Quarter-level clinical and subclinical mastitis were lower in vaccinates compared to the control group. Similarly, the somatic cell count was consistently lower in the vaccinates compared to the control group, although the difference was not statistically significant. The vaccine also decreased the S.uberis shedding duration from 6 to 2 days in vaccinates.
No severe adverse reactions were observed after vaccine injection, except for transient increases in rectal body temperature and injection site reactions following vaccination.Serum and milk anti-SCSP IgG titers were significantly higher in vaccinates, particularly at 30 days in milk post-calving. These results prove that the SCSP vaccine confers significant protection against S. uberis mastitis, reducing both clinical and subclinical mastitis and supporting its potential as a sustainable alternative to antibiotics for the control of S. uberis mastitis in dairy cows
Safety Performance of High Burnup and Extended Enrichment Pressurized Water Reactor Fuels
No full textEfforts to introduce new cladding materials and fuel systems are being pursued by several major fuel vendors, with substantial interest from operating utilities. These designs have the potential to provide economic benefits, notably in the ability to extend the operating cycle length of pressurized water reactors from 18 to 24 months. To support this increase, these fuel forms must be rigorously shown to meet adequate safety criteria under long term irradiation and during design basis accidents. Current challenges in developing this technical basis include demonstrating the feasibility and safety of fuels with UO2 enrichments greater than 5% and burnup levels greater than 62 GWd/MTU.
The first two studies presented in this work consider two proposed near-term high burnup core designs using differing burnable poison strategies to meet design constraints. The safety analysis simulation tools PARCS and RELAP5-3D were used to evaluate the designs based on their normal operating cycle performance and safety performance during reactivity-initiated accidents. Loss of coolant accident performance was also analyzed, including an assessment of fuel performance behavior with BISON. High soluble boron concentrations likely prevent the implementation of an ZrB2 integral-fuel burnable poison design without significant design iteration. From a safety perspective, the two designs perform well for both control rod ejection and loss of coolant accidents. Future designs should aim for improved hydriding resistance and reduced rod internal pressures. Additional efforts should be made to reduce linear heat rates of rods at intermediate burnups to gain additional safety margin.
To further support model development and physical understanding of high burnup fuel behavior, a sensitivity analysis was performed to characterize the impacts of thermal property and two-phase boiling uncertainties on fuel safety predictions during reactivity-initiated accidents. These uncertainties were found to be highly significant for predictions of fuel behavior. Further work is needed to develop mechanistic cladding failure criteria appropriate for this accident type.
This work identifies high impact areas of need for model development relevant for fuel safety and makes recommendations for future high burnup core designs. These developments will be necessary to achieve the adoption of high burnup pressurized water reactor fuels
Democracy in the Margins: The Case of Iraq as an External Critique of Liberal Democracy
No full textLiberal democracy, as ambiguous of a concept as it is, has been both praised and celebrated as the End of History (Fukuyama, 1992) and critiqued for its internal contradictions. In the West, there have been rich traditions of internal critiques, focusing on the inability of liberal-democratic political systems to reduce or alleviate persistent social inequalities, including racial, class, and gender inequalities, the challenge of creating and sustaining spheres for public deliberation, elite domination, and its incompatibility with capitalism and disenfranchisement.
This thesis extends such efforts to critique the challenges of the system by answering calls to bring perspectives external to the Western world into conversation. It specifically focuses on the Iraqi historical case, as a society that had a bittersweet experience with imposed liberal democracy. It attempts to answer the ways the case of post-2003 Iraq offers an external critique of liberal democracy that complements or contradicts existing internal critiques in Western social theory.
To achieve such objectives, the thesis provides a typology of internal critiques, focusing on three specific traditions that are complimentary to one another and comparatively compatible to the Iraqi case. These traditions include elite, public sphere, and social justice perspective. After constructing the typology, the thesis implements comparative historical methods to both trace the fundamental developments in post-2003 and compare how Iraqi scholarly perspectives contradict or compliment the Western internal critiques.
The thesis illustrates that while Iraqi scholars agree with Western critiques in terms of problems with elite domination, public sphere deficits, and inequality, they also add that monopoly on violence, constructing a shared national identity, and countering regressive tribal and ethno-religious tendencies is necessary for a functioning governance system
Tracking changes in nonprejudiced motivations: Influences of social and political events
No full textThis study examined changes in nonprejudiced motivations toward Black people over the 2017-2024 periods. It also explored gender difference in motivations to control prejudiced reactions. The sample was 11064 White undergraduate students (3589 male, 7348 female, and 127 individuals identifying as non-binary) from the University of Tennessee. Nonprejudiced motivations was measured using the Motivation to Control Prejudiced Reaction (MCPR), assessing concern with acting prejudice and restraint to avoid dispute subscales. Results indicated that both concern and restraint motivations increased after the George Floyd murder, then decreased at following time points. In addition, results showed that, mirroring political trends, concern gradually rose among women and stayed flat among men prior to 2020.
Keywords: prejudice, motivation, social norm
Exploring the Performance of Low-Cost Part Scanning in Wire Arc Additive Manufacturing
No full textWire arc additive manufacturing (WAAM) is a metal additive process which utilizes traditional welding equipment in conjunction with robotic manipulators to create metal parts for a variety of applications. The WAAM process requires material deposition which involves rapid material melting and solidification. Heating and cooling cycles are extensive and produce internal material stresses in turn creating distortion. Distortion can become extensive and commonly produces nonconforming parts, reducing yield, and increasing manufacturing time and cost. To address these challenges, 3D scanning can be employed as an in-situ monitoring technique to detect distortion as it develops by gathering accurate scans in-between layers. Surface measurements using 3D scanning are desired with uncertainties below 1 mm. Existing scanning solutions already exist, but are expensive and difficult to co-locate in welding cells where excessive operating temperatures, weld spatter, and airborne soot often occur. Therefore, a low-cost solution is necessary. Combining an inexpensive depth sensor, a robotic manipulator already utilized for WAAM processes and data processing scripts creates a promising solution for low-cost 3D scanning. Open3D integration is utilized alongside aligned image frames with robot position data. Performance experiments were conducted to access the system’s capability and limitations using test artifacts of different shapes and sizes. Robot scan velocity was varied to test effects on surface reconstruction. Experiments scanning test artifacts shows the low-cost system is capable of producing meshes accurate to 1 mm. Test artifacts also demonstrated limitations of the system when evaluating parts with low-texture and sharp edges being prone to poor scan quality. Experiments were conducted during WAAM processes and demonstrate the ability of the system to be implemented in-situ to monitor part geometry
2025 ATMI National Convention (Spokane, WA)
No full textThis file lists the papers, compositions, performance/papers, workshops, and demonstrations presented at the 2025 ATMI National Convention, in Spokane, WA October 30 - November 1, 2025
Political Humor in the Public Sphere: Analyzing the Effects on Public Perception and Civic Engagement
No full textRACIAL IDENTITIY DEVELOPMENT OF UNDERGRADUATE STUDENTS ENGAGING IN THE COMMUNITY SCHOOLS CONTEXT
No full textThis study examined the racial identity development of undergraduate students participating in service-learning experiences within Community School contexts. Grounded in the theoretical frameworks of Critical Race Theory, Critical Whiteness Studies, and Racial Identity Development Theory, the study examined how service-learning experiences might influence participants’ understanding of race, social justice, and their own positionality as future educators. Using a sequential explanatory mixed methods research design, the study began with the administration of the White Racial Identity Attitudes Scale (WRIAS) to 30 undergraduate participants.
Quantitative findings revealed statistically significant shifts in racial identity statuses over the course of the semester. The change in statuses was most notable between the earlier statuses of Contact and Disintegration with a correlation to Pseudo-Independence within the generated racial identity development profiles. Based upon the quantitative results, 3 participants were selected for in-depth, semi-structured interviews to further explore their perceptions of Community Schools and the factors contributing to changes in their racial identity development. Thematic analysis highlighted how direct engagement with Community Schools prompted students to confront colorblind ideologies, examine their own identities, and articulate emerging commitments to educational equity. Participants described these experiences as transformative, often citing specific interactions with students and teachers from their service-learning placements.
The findings suggested that Community School contexts can serve as powerful sites for racial identity development, particularly when paired with structured opportunities for critical reflection. This research contributed to the broader field of education by illustrating the potential of service-learning to not only enhance awareness of issues of social justice but also support the development of racially conscious educators. Implications include the need for intentional curricular integration of racial identity work and a shift to viewing service-learning as a social-justice driven pedagogical practice
Modeling Host-Pathogen Systems with Differential Equations and Integral Projection Models
No full textMathematical modeling can serve as a tool for understanding complex biological systems and elucidating host-pathogen interactions. We illustrate the utility of mathematical modeling applied to host-pathogen systems by presenting three mathematical modeling frameworks. The first two frameworks are applied to within-human-host Plasmodium falciparum malaria and the third framework is applied to the fungal pathogen Batrachochytrium salamandrivorans (Bsal).
Human malaria is a vector-borne disease caused by Plasmodium parasites transmitted through the bite of an infected Anopheles mosquito. Within-human-host malaria dynamics are complex, involving several parasite life-stages, including asexual replication (the parasite stage associated with symptom onset), and sexual development into gametocytes (the parasite stage responsible for human-to-mosquito transmission). When considering new antimalarial treatments, approaches that balance reduction of asexual parasite forms (and thus morbidity and mortality) with the selection of drug resistant parasites are needed. We present a within-host differential equations model that includes time-dependent drug dynamics to assess the impact of a triple artemisinin-based combination therapy (TACT) on the probability of human-to-mosquito transmission. For our second malaria model we develop a more biologically realistic and flexible model framework of within-host dynamics that allows for arbitrary distributions for the waiting times for each red blood cell and parasite life cycle stage. Using the model, we assess how varying the distribution assumptions impacts the probability of human-to-mosquito transmission.
Integral projection models (IPMs) provide a framework for using individual-level demographic data to make population-level predictions. However, if not properly accounted for, measurement error in individual-level experimental data can have effects that propagate through the model and bias predictions. To address this limitation, we develop an Integrated Survival Model Framework (Integrated IPM) that combines individual-level demographic data with host death time observation data to parameterize an IPM, from which we can predict emergent survival curves. We illustrate the ability of the Integrated IPM to account for measurement error by testing the model on simulated host-pathogen load data that contains measurement error. We then apply the Integrated IPM to experimental data from adult and juvenile eastern newts, salamander hosts susceptible to the fungal pathogen Bsal