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Perceived Stress and Moral Judgment Among College Students: Bridging the CNI Model and bDIT Framework
No full textElectronic Thesis or DissertationThis study investigates the relationship between perceived stress and society-wide moral judgment through the integration of two prominent frameworks: the neo-Kohlbergian approach and utilitarian-deontological (U-D) judgment. To pave the way, the methodological and theoretical foundations required to advance this understanding were also explored.Study 1 fills the methodological gap in the CNI test, which provides a better experimental design for conceptualizing and measuring U-D judgment. The EIRTree-CNI model was introduced, which, compared to the original CNI test, allows for individual-level measurement. Validation of the model demonstrated improved fit and reliability compared to traditional methods, offering a robust tool for future research. Study 2 examines the interplay between the two frameworks in relation to society-wide moral judgment. The neo-Kohlbergian approach to moral judgment proposes three moral schemas: (1) Personal Interest (PI), where decisions are self-focused; (2) Maintaining Norms (MN), which emphasizes adherence to social rules and norms; and (3) Postconventional (PC), where universal ethical principles are prioritized. The CNI model for U-D judgment features three psychological processes in decision making: Sensitivity to Consequence, Sensitivity to Norm, and Inaction Preference. The results indicated that PC schema adoption is positively correlated with Sensitivity to Consequence; MN schema adoption is positively correlated with Sensitivity to Norm and negatively correlated with Sensitivity to Consequence; and PI schema adoption is negatively correlated with Sensitivity to Norm. Additionally, a curvilinearly relationship was identified between MN schema adoption and Sensitivity to Consequence. Finally, study 3 explores the relationship between perceived stress and moral judgment. The results indicate that increased perceived stress is associated with increased PI schema adoption, reduced Norm Sensitivity and increased Consequence Sensitivity. Notably, PI schema was identified as a mediator in the relationship between perceived stress and Norm Sensitivity. This research advances our understanding of how perceived stress shapes moral judgment
Surface Engineering of Critical Metallic Components: a Critical Evaluation of the Effectiveness of High Energy Laser Peening and Shot Peening of Ni-Cr-Mo Steels and Alloy 625
No full textElectronic Thesis or DissertationThis dissertation includes a thorough investigation into the effects of high energy multi-layer laser peening (LP) and shot peening (SP) of Ni-Cr-Mo high-strength low-alloy (HSLA) steels including 4340 and 300M and the Ni-Cr alloy, alloy 625 (Inconel 625). In this work the effectiveness of these two different surface engineering techniques has been evaluated to determine how the mechanical properties and microstructures of these alloys evolve following deformation and how these evolutions in material properties enhance these alloys’ resistance to wear, corrosion, and exposure to high temperature. Advanced characterization techniques have been used to draw correlations between local mechanical properties and microstructural alterations resulting from surface engineering of these alloys to understand their structure-property relationships.The first two studies compare the effects of high energy multi-layer LP and full coverage SP on the mechanical properties and microstructural evolution of two Ni-Cr-Mo HSLA steels including 4340 and 300M, while the third and fourth studies investigate the effects of these techniques on alloy 625. In the first study the local mechanical and microstructural properties of 4340 steel with a pearlitic microstructure were investigated following surface engineering. In the second study these techniques were used to pretreat 300M prior to high-velocity oxygen fuel (HVOF) deposition of a WC-Co coating to investigate the impact of these techniques on enhancing the corrosion fatigue life of WC-Co coated 300M. The third study exploits the age-hardenability of alloy 625 by employing multi-layer high energy LP and SP prior to aging to locally accelerate the nucleation and precipitation of γ՛՛ and δ intermetallic phases. The final study includes an analysis on the effects of high energy multi-layer LP and SP on the mechanical, microstructural, and tribological properties of centrifugally-cast alloy 625. In summary, this dissertation examines three different engineering alloys that are used to manufacture components used in critical applications to understand how these alloys’ mechanical properties and microstructures evolve following surface engineering. This work highlights these alloys’ susceptibility to plastic deformation based on their underlying microstructures and demonstrates how these surface engineering techniques can be employed with other manufacturing or processing techniques to further enhance their capabilities
Three Essays on Corporate Governance and Corporate Social Responsibility
No full textElectronic Thesis or DissertationThis dissertation presents three essays on corporate governance and corporate social responsibility (CSR). As key decision-makers in a firm’s internal governance, chief executive officers (CEOs) and the board of directors play a crucial role in shaping corporate policies. This dissertation explores their influence and examines whether shifts in firms’ CSR policies reflect genuine change or merely serve as window dressing. In the first essay, we examine the effect of CEOs’ outside directorship experiences on their home firms’ CSR ratings. We discover a positive association between the CSR scores of CEOs’ outside directorship firms and their home firms’ CSR scores. Moreover, the greater the difference between the CSR scores of the directorship firms and the CEOs’ home firms, the greater the subsequent change in the CSR scores of the CEOs’ home firms, providing evidence of CSR propagation. The propagation is more evident in the social than the environmental dimension, which is less heterogeneous across different industries. Our results underscore the director labor market’s important role in propagating CSR ideas. In the second essay, we explore whether firms voluntarily respond to local social issues. We explore this question through state-level hospital policies that promote breastfeeding. While these policies have a positive inter-generational impact on infants, they also create challenges for the female workforce. Although firms are not required to respond, some proactively adapt by creating a more parenting-friendly work environment. These improvements are concentrated in firms with greater female and minority representation on their boards and those with a high female labor dependency. While these voluntary efforts enhance employee satisfaction, they do not significantly affect firms’ operating performance. In the third essay, we examine the monitoring role of directors who are CEOs of other firms (CEO-directors). Given mixed evidence from prior studies using traditional monitoring functions, we rely on distinct data on federal-level violations. We find that CEO-directors are associated with more corporate misconducts, driven by their distinct services other than monitoring roles. The results suggest that different directors would contribute heterogeneously, prompting a necessity for corporate stakeholders to carefully consider board composition based on their expectations
Police interrogation and fraudulent epistemic environments
No full textOpen Access ArticleThe police are required to establish probable cause before engaging in custodial interrogation. Much custodial interrogation relies on a fraudulent epistemic environment (FEE) in which the police knowingly use deception and dishonesty to gain an advantage over a suspect regarding a material issue, injuring the interests of the suspect. Probable cause, then, is a sort of evidentiary and epistemic standard that legally justifies the police’s use of deceptive and dishonest custodial interrogation tactics that are on par with fraud. However, there are both deontological and consequentialist considerations that show why the police’s use of an FEE is often unjustified. Accordingly, the paper argues that even if the use of an FEE is based on probable cause, there are other (non-epistemic) reasons to think evidence with probative value (such as a confession) should be excluded when derived from an FEE and there is no acute threat of harm to others
Effects of Compressibility and Variable-Density on the Instability Growth within Buoyancy-Driven Shear Layers
No full textElectronic Thesis or DissertationDirect numerical simulations are performed to examine the effects of compressibility and compositional variable density (VD) on the instability growth within buoyancy-driven shear layers (BSL), which share characteristics with the canonical Rayleigh-Taylor (RT/RTI) and Kelvin-Helmholtz (KH/KHI) instabilities. The 2D simulations are performed in a periodic domain, with alternating columns of high and low density fluids and neutral background stratification. This study expands upon work previously done by Gat, Matheou, Chung, et al. in the incompressible regime. The Atwood number A, and the isothermal Mach number Ma, are varied to investigate the effects of variable density and compressibility on the BSL, respectively. The results suggest that the flow exhibits two distinct flow regimes. An early time regime is driven by shear instabilities and experiences minimal compressibility and variable density effects with the characteristics of KHI; the second regime follows and is driven by buoyancy while exhibiting certain similarities with RTI. It was found that as A increases, the BSL enters the second regime more quickly in non-dimensional time. In this regime, compressibility has a suppressive effect on the growth of the mixing layer and the heights of the bubble- and spike-like structures, even though the background stratification is neutral due to the homogeneity. Compressibility also enhances the heavy and light fluid mixing asymmetry induced by the variable density effect, a phenomenon observed in RTI. It also leads to a more mixed mixing layer, resulting in less large-scale mixing with shorter pure fluid penetrations across the initial interface. In addition, the reduced interfacial density gradients due to molecular mixing lead to a weakening of the baroclinic torque, the primary vorticity production term. This can lead to a concentration of vortical motions at dissipative scales, which eventually results in the cessation of mixing layer growth with sufficiently strong compressibility effects. Lastly, it is observed that the suppressive effect of compressibility appears to be enhanced by a greater A. Thus, greater A induces the flow regime transition more quickly, but also leads to greater instability suppression through compressibility at later times. In this way, compressibility and VD effects are coupled while also competing
Case Study on Successful School Leadership in Alabama During the Pandemic and in Post-Pandemic Era
No full textElectronic Thesis or DissertationThis mixed methods case study investigated school stakeholder perspectives, including a principal, teachers, students, and parents, of a Northern Alabama high school, examining the development, attainment, and sustainment of successful school principalship premised on and a contributor to the International Successful School Principalship Project (ISSPP). The aim of the study was to identify both the leadership qualities and the practices of the principal in the Alabama high school before, during, and after the COVID-19 pandemic. This study was guided by an agreement to the following ISSPP precepts: (a) richer and more authentic data require a multi-perspective evaluation, (b) such data are best acquired by those with close, familiar knowledge (i.e. principal, teachers, students, and parents), (c) and collaborative research provides understanding and insights into successful school principalship. To an extent, effective and successful school leadership is already "known." While leadership varies depending upon contexts and populations and there exists a widely understood body of evidence about effective leadership, gaps still remain. This study's participants identified their perceptions of successful school leadership. Findings indicate that successful principalship in Alabama has a strong emphasis on continuous development and strategic resource management to cultural embed an environmental resilience. Interviews and survey data revealed that principals who foster stakeholder collaboration, provide professional and personal support, and engage within and as a community can effectively develop, achieve, and sustain success
Development of an Economical Ultra-High-Performance Concrete Mix Using Local Materials
No full textElectronic Thesis or DissertationUltra high-performance concrete (UHPC) is an advanced cementitious composite material characterized by an optimized gradation of granular constituents, a water-to-cementitious materials ratio of less than 0.25, and a high percentage of discontinuous internal fiber reinforcement. UHPC exhibits exceptional mechanical properties in comparison to traditional concrete, including a compressive strength greater than 17.4 ksi (120 MPa) and a post-cracking tensile strength greater than 0.72 ksi (5 MPa). Due to these exceptional mechanical properties and durability properties, UHPC is being increasingly utilized in critical infrastructure projects, such as nuclear waste containment facilities, precast structural connection joints, bridge girders, and bridge deck systems. However, the high cost of commercially available, pre-bagged UHPC remains a significant obstacle. This study aims to develop a cost-effective, nonproprietary UHPC mix design using materials that are readily available in Alabama. Thirty-five trial mixes were produced to optimize non-proprietary UHPC formulations for local materials available in the southeast region. The mix design iterations focused on adjusting supplementary cementitious materials (SCMs), water/cementitious material ratio, fines and type, cement type, and high-range water reducer (HRWR) dosage. The study investigated the effects of binder and HRWR type and content, SCMs, sand type, and curing regimes on the compressive strength of the UHPC. An optimal mix that achieved the desired workability and strength was selected for further evaluation through standard ASTM testing methods. The mixes developed in this research exhibited a minimum static flow of 10 inches. The presence of large quantities of cementitious materials can result in high shrinkage strains. The measured shrinkage strains for the UHPC mix developed in this study varied between 400 to 600 ε. The mechanical propertiesof UHPC evaluated in this study include compressive strengths of approximately 19 ksi (131MPa) and elastic modulus varying from 6000 ksi to 6400 ksi. The stress-strain behavior of the UHPC in tension is evaluated using a four-point bending test and the inverse analysis. The measured tensile strength of the UHPC mixes varied between 1.55 to 1.7 ksi, with localization strains of 0.004-0.006 in./in. The Rebar development length in UHPC was experimentally investigated using modified pull-out tests. It was found that an embedment length of 10db (wheredb = diameter of rebar) in UHPC with a clear cover of 2db is sufficient to yield Grade 60 mild steel reinforcement
The Influence of Chronotype on Cardiovascular and Metabolic Health Profiles in Young Adults
No full textElectronic Thesis or DissertationBACKGROUND: Circadian rhythm is the process that regulates the sleep-wake cycle in our bodies, repeating approximately every 24 hours. This process controls various physiological processes, and when disrupted, circadian misalignments can lead to cardiometabolic dysfunction and disease. Chronotype is the behavioral manifestation of circadian rhythm, reflecting when one feels high or low energy during the day. Individuals are broadly categorized as morning (wake up early, feel most alert in the morning) or evening (wake up late, feel most alert in the evening) chronotype. Growing evidence suggests that an evening chronotype is associated with an unfavorable cardiometabolic risk profile in middle-aged and older adults. Less is known about chronotype and cardiometabolic risk in younger adults, resulting in a crucial gap in understanding how early-life behaviors influence long-term health outcomes. PURPOSE: To investigate the influence of chronotype on cardiometabolic health among young adults (18-40 y) using a comprehensive assessment battery and examine whether these differences are mediated by habitual lifestyle factors. METHODS: 68 young adults (20±3 y, 69% women, 72% White, 26.6±6.7 kg/m2) were stratified into two groups: morning (n=33) and evening (n=35) chronotype, using the Morningness-Eveningness Questionnaire. Participants underwent assessments of body composition, cardiometabolic health (e.g., blood pressure [BP]), arterial stiffness, fasted cholesterol and glucose levels), physical activity (PA), and sleep. Participants wore an ambulatory BP monitor and accelerometer to measure BP, PA, and sleep parameters for 24 hours. RESULTS: Greater eveningness was associated with less favorable behavioral profiles, including reduced light and moderate PA, more sustained inactivity, poorer sleep quality, greater social jetlag, and poorer diet quality (p≤0.05 for all). Individual cardiometabolic measures did not differ by chronotype, however, evening chronotype was associated with higher cardiometabolic risk using composite scores (Framingham risk, Life's Essential 8). No behavioral or sleep-related variables significantly mediated the association between chronotype and cardiometabolic risk. CONCLUSIONS: This study is among the first to comprehensively examine chronotype and cardiometabolic health in young adults using both self-report and device-based measures. Findings support an emerging role for chronotype in shaping cardiometabolic risk and highlight the need for longitudinal studies and tailored interventions addressing circadian alignment in at-risk individuals
Evaluating the Effect of Laser and Shot Peening on Hydrogen Diffusivity and Trapping and Corrosion Susceptibility in High Strength Steel
No full textElectronic Thesis or DissertationThis thesis will present work on the effect of laser peening and shot peening on hydrogen diffusivity and trapping in 4340 high strength steel, along with corrosion behavior. Surface engineering, such as laser peening and shot peening, imparts plastic deformation resulting in compressive residual stresses and increased dislocation densities. This has been shown to dramatically increase fatigue life in various materials and applications. However, due to the sensitivity of high strength steels to hydrogen embrittlement, it is unknown how the increased hardness and dislocation density caused by laser peening will affect processes related to hydrogen-influenced cracking. In this work, electrochemical procedures were used to assess these structure-property relationships. Hydrogen permeation testing was conducted per ASTM G148-97, which allowed for calculating the effective hydrogen diffusivity of laser peened, shot peened, and unpeened 4340. Hydrogen trapping was also evaluated through electrochemical potentiostatic hydrogen charging and discharging. A roughly order-of-magnitude decrease in diffusivity was found within the laser peened region due to the increase in trap density