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The Prudential Rationality of Risking Traumatic Brain Injury in Dangerous Sport: A Parfitian Defense
No full textIt is an open question whether participation in dangerous sports is prudentially rational given the high risk of traumatic brain injury they involve. This paper explores the merits of one attempt to rationalize participation in dangerous sport, which is based on Derek Parfit’s idea that it is rational for you to care less about the well-being of your future selves the more distant they are, because time diminishes the degree of their psychological connectedness to your present self. I respond to two sets of concerns about this defense of dangerous sport. First, there are concerns that the Parfitian defense is too weak to justify taking such serious risks as dangerous sport involves—specifically, objections based on an appeal to the overall shape of one’s life, as well as objections from self-directed duties. Second, there are concerns that the Parfitian defense would prove too much—specifically, that it would rationalize generally reckless risk-taking for fun; and that it would make one exploitable. I show that none of these objections succeeds, and I conclude that the Parfitian defense remains tenable.Philosoph
Comprehensive Assessment of Physiological, Biochemical, and Reproductive Parameters of Crossbred Goats in Response to Bee Pollen Supplementation
No full textGoat populations in the United States have decreased since 2012, while consumer demand for goat products have continued to grow. As a result, more than two-thirds of the goat meat consumed in 2023 was imported. One contributing factor to the limited domestic supply may be due to suboptimal nutrition, which can negatively impact goat health and reproductive efficiency. Identifying and implementing nutritional strategies that could enhance goat productivity and herd health could help mitigate this issue, increase domestic production and reduce reliance on imports. Bee pollen (BP) is known for its antioxidant, antimicrobial, and immunomodulatory properties, and has been promoted to humans as a natural supplement. The objective of this study is to determine if physiological, biochemical, and reproductive performance, of crossbred goats can be improved through the supplementation of BP. Procedures utilizing animals were approved by the Texas State IACUC prior to project initiation. During the sub-optimal breeding season (late summer to early fall), when decreasing day length and high temperatures can negatively impact reproductive performance, crossbred Spanish × Boer doelings (n=30) were housed in two separate 0.405 ha paddocks. Animals had access to limited grazing and were provided a supplemental diet formulated to meet their maintenance nutritional requirements. Animals either receive 10g/head of BP or did not receive any BP supplementation. Weekly assessments of BCS, LW, and blood samples were conducted, while fecal egg counts (FECs) were performed biweekly during the experiment. Blood samples were analyzed for hepatic enzyme activity, hormonal concentrations, and metabolic status. The statistical analysis for this study was conducted using the MIXED procedures of SAS software. Pens were considered the experimental unit for grouped variables, while individual animals were treated as experimental units for hematological and parasitological analysis. Analysis of variance (ANOVA) was used to look at fixed effects of treatment, time, and their interaction, with significance set at P ≤ 0.05, and tendencies noted when 0.05 < P ≤ 0.10. No significant differences were detected between the treatment (T-BP) and control (T-CTL) groups across the measured parameters. However, numerical trends suggested possible improvements in anemia-related indicators in the T-BP group. These preliminary findings show the need for further research with longer supplementation periods, larger sample sizes, and varying dosages to further evaluate the benefits of BP in small ruminant production.Agricultural Science
C14DM Ablation Leads to Reduced Tolerance to Plasma Membrane Stress and Increased Drug Sensitivity in Leishmania major
No full textSterol biosynthesis is crucial for the function of biological membranes and an important target for anti-protozoan/anti-fungal drugs. In the trypanosomatid parasite Leishmania major, the deletion of sterol C14-demethylase (C14DM) results in hypersensitivity to heat, increased plasma membrane fluidity, profound mitochondrial dysfunctions, and reduced virulence in mice. In this study, we show that C14DM-null mutants are defective in their tolerance to membrane-disrupting agents and osmotic stress and their ability to form autophagosomes. In addition, C14DM-null mutants exhibit a heightened sensitivity to anti-trypanosomatid drugs including antimony, ethidium bromide, and pentamidine. The combination of itraconazole (a C14DM antagonist) and pentamidine synergistically inhibits the growth of Leishmania parasites. These findings reveal new insight into the roles of sterol synthesis in protozoan pathogens and highlight the potential of using drug combinations to achieve better treatment outcomes.Biolog
Correction: Lee and Choi (2025). Changes in Aggressive Behaviors over Time in Children with Adverse Childhood Experiences: Focusing on the Role of School Connectedness. Social Sciences 14: 385
No full textNo abstract prepared.Social Wor
Oral history interview: Lee E. Lefler
No full textEdited and unedited transcript files (.pdf) and edited and unedited video files available with closed captioning.Oral history interview with Jerry Lefler about Lee E. Lefler
Identification of Dichotomous Communities in Signed Graphs Using Coherence-Based Metrics
No full textIn this thesis, we investigate and extend a system of coherence-based metrics on signed graphs. We apply these metrics to the problems of community identification, error correction, and analysis of anomalous real-world data. We begin by exploring the distribution of "nearby" balanced states of signed balanced graphs and conjecturing a relationship between this distribution and the frustration index of the signed graph. We continue by describing the coherence-based metrics originally described by Rusnak and Tešić, extending their classification of these metrics and adding one additional metric, fragility. In the process of exploring the properties of these metrics, we introduce the influencer network, a synthetic signed graph which exhibits human-like behavior and allows for injection of two kinds of noise.
Equipped with these metrics, we present a method for error-correction based on fragility, describe three community detection methods based on the distribution of nearby balanced states, and present initial benchmarks of these compared against Signed Louvain's method. Finally, we use our classification of how the coherence-based metrics are impacted by noise injection to hypothesize the cause of certain anomalies in FBI crime rate data.Mathematic
Wear Resistance of Additively Manufactured Footwear Soles
No full textThis study systematically evaluated the wear resistance and mechanical performance of 3D-printed thermoplastic rubber (TPR) and flexible stereolithography (SLA) resin materials for footwear outsoles. Abrasion tests were conducted on 26 samples (2 materials × 13 geometries) to analyze the weight loss, variations in the friction coefficient, temperature change, and deformation behavior. Finite element method (FEM) simulations incorporating the Ogden hyperelastic model were employed to investigate the stress distribution and wear patterns. The results revealed that TPR exhibits superior abrasion resistance and stable wear curves, making it suitable for high-load applications. On average, the TPR samples showed 27.3% lower weight loss compared to the SLA resin samples. The SLA resin samples exhibited a 65% higher mean coefficient of friction (COF) compared to the TPR samples. Furthermore, the SLA resin samples demonstrated a 94% higher temperature change during the sliding tests, reflecting greater friction-induced heating. The FEM simulations further validated TPR’s performance in high-stress regions and SLA resin’s deformation characteristics. This study’s findings not only highlight the performance differences between these two 3D-printed materials but also provide theoretical guidance for material selection based on wear behavior, contributing to the optimization of outsole design and its practical applications.EngineeringEngineering Technolog
Impact of Kalanchoe (Kalanchoe daigremontiana) Supplementation in Goat Maternal Diet on Hepatic and Renal Function and Reproductive Performance
No full textKalanchoe daigremontiana, a medicinal plant rich in bioactive compounds, has the potential to serve as a feed supplement, reducing reliance on conventional livestock medications while potentially enhancing productivity. This study evaluated the effects of K. daigremontiana supplementation over 52 days on kidney and liver function, metabolism, weight changes, and reproductive efficiency in multiparous Alpine goats during the breeding season. Fifty-five goats were assigned to either a control (CTL, n = 27; 47.6 ± 1.1 kg) or a K. daigremontiana-supplemented (KAL, n = 28; 47.6 ± 1.3 kg) diet. The KAL group received K. daigremontiana at a dry matter-based inclusion rate of 2 kg t−1 of feed, while the CTL group received no supplementation. Blood samples were collected at four time points to assess the biochemical markers of kidney and liver function. Pregnancy was achieved through natural mating, and reproductive efficiency was evaluated. Overall, liver and kidney function did not differ significantly between treatments (p > 0.05). However, KAL supplementation was associated with increased creatinine (p < 0.05), ALP (p < 0.001), and bilirubin (p < 0.05) at specific time points, whereas CTL goats exhibited higher BUN (p < 0.001), AST (p < 0.05), albumin (p < 0.001), total protein (p ≤ 0.05), and phosphorus (p < 0.01) on specific dates. Other metabolic markers, weight gain, and reproductive efficiency did not differ between treatments (p > 0.05). Overall, Kalanchoe daigremontiana supplementation had mild, transient effects on goat health without significantly impacting productivity. Further research is needed to explore its long-term effects and optimal dosage for livestock nutrition.Agricultural Science
Examination of Tension, Resistance, and Survival: Black Girls in Educational Settings in the Jim Crow Era
No full textThis narrative inquiry explores the stories of five Black girls and their educational journey during the Jim Crow era. The participants reveal the intersectionality of race and gender as they re-late to their experiences in segregated and desegregated schools in the South and Midwest. The sto-ries served as a vessel to reveal the reality that existed during a time of oppression, systematic rac-ism, and inequitable and discriminatory practices. Five participants were interviewed in a semi-structured format via the Zoom platform, revealing complex and dynamic stories through the con-ceptual frameworks of Black feminist thought and ecologies of knowing. The thematic findings were anchored around the intersectionality of race and gender, highlighting their experience through the lenses of self, organization, and community. The following sub-themes emerged: inter-nalized understanding of race, caring relationships (influence), desegregation, familial expectations to attend school, and separate but equal. The findings uncovered that the development of their self-concept was influenced by supportive relationships with parents and educators, specifically Black women who were their teachers. Although the intent behind Brown v. Board of Education was to create equitable learning experiences for Black students, the participants in this study shared the confusion they experienced, along with the misunderstanding of how the local leader went about the process of segregation. However, through it all, the participants shared the value their family placed on education and attending school despite the turmoil and tension that existed during that era.Educatio
Atmospheric Water Generation through Thermoelectric Cooling Optimization and Surface Customization
No full textAtmospheric Water Generation (AWG) represents a promising and sustainable solution to global water scarcity by enabling the extraction of moisture directly from ambient air. This thesis presents an integrated approach to enhancing AWG efficiency through thermoelectric cooling, geometric surface engineering using Triply Periodic Minimal Surfaces (TPMS), data-driven optimization via machine learning, and experimental validation under various operating conditions. Thermoelectric coolers (TECs), particularly Peltier modules, were utilized to generate the necessary temperature differential for condensation. A range of configurations was explored, including fan-assisted and passive heat sink setups, to evaluate the impact of thermal management on condensation performance. The study found that while fan-assisted cooling of the hot side improved cold-side efficiency, excessive voltage led to heat backflow and early frost formation, ultimately reducing water yield. Environmental factors such as airflow, relative humidity, room temperature, dew point, and evaporation were considered noise factors and were monitored but not controlled during the experiment. To optimize the geometric design of condensation surfaces, a machine learning framework was developed to model the relationship between TPMS design parameters—such as lattice thickness, cell size, and surface area-to-volume ratio—and resulting surface temperature. Among several algorithms tested, Decision Tree Regression outperformed others (R² = 0.9676), offering an accurate and interpretable model to guide rapid geometry selection without extensive physical trials. This predictive model provides a foundation for future closed-loop design systems in AWG applications. Building on the insights from the machine learning model, six TPMS geometries—Schwarz, Gyroid, Diamond, Neovius, Lidinoid, and Split-P—were evaluated for fabrication using multi-axis CNC machining from Aluminum 6061-T6. While Schwarz and Neovius geometries were successfully produced, others posed significant challenges due to complex curvature and tool accessibility issues. The feasibility of subtractive manufacturing was demonstrated, particularly for moderate-volume production where material cost, surface quality, and thermal performance are prioritized. Experimental results showed that TPMS-based surfaces, especially Schwarz structures, improved water yield at moderate TEC voltages (5–6V) due to enhanced surface area and curvature-driven droplet mobility. However, at higher voltages (≥7V), early icing reduced performance, highlighting the need for active temperature control and anti-frost strategies. Overall, this research establishes a multi-disciplinary pathway to develop energy-efficient and scalable AWG systems by integrating thermal optimization, data-driven geometric design, and precision fabrication. The outcomes provide a robust framework for future innovations in sustainable water harvesting technologies applicable to off-grid, remote, and climate-challenged environments.Engineerin