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Effects of John Henryism Active Coping and Lifetime Discrimination on Sleep Outcomes
No full textBecause of racism, many Black Americans feel like they must exert extra effort and determination to succeed. This is called John Henryism Active Coping: feeling that because of one's race, one will always have to work harder than others in life to succeed. John Henryism Active Coping harms physical health by exaggerating biological responses to stress (James, 1994). Little is known about the sleep implications of using John Henryism Active Coping to cope with racism. The current study examines how lifetime racial/ethnic discrimination and John Henryism Active Coping influences Black and African American young adult's sleep health. A sample of 552 Black and African American young adults completed an online questionnaire reporting their exposure to lifetime discrimination with 4 items (e.g. "In your lifetime, about how often did you experience discrimination in publics, like on the street, in stores, or in restaurants?", α=.847), and active coping via the John Henryism Active Coping Scale (James et al., 1987). Sleep was measured using one item "On average, how many hours of sleep do you get in a 24-hour period?" Total household income, generation status, student status, gender, marital status, and employment status were covariates. Hierarchical linear regression showed active coping was associated with shorter sleep (B=-1.159; p<.001), while lifetime discrimination was associated with longer sleep (B=0.568; p=.005). Racism influences sleep in various ways by possibly increasing sleep as coping when considering lifetime experiences of racism, but also activating stress arousal and reducing sleep duration when combined with active coping.Psychological, Health, and Learning Sciences, Department ofHonors Colleg
Structural Repurposing of Decommissioned Wind Turbine Blades for Civil Infrastructures
No full textThe global expansion of wind energy has resulted in a growing stockpile of decommissioned wind turbine blades (DWTBs), which are composed primarily of glass fiber-reinforced polymer composites. Due to their thermoset nature, complex geometry, and large size, these blades are difficult to recycle using conventional methods. This dissertation presents a novel and sustainable alternative, the structural repurposing of DWTBs for civil infrastructure applications, aligning with circular economy principles and supporting carbon reduction goals. The research focuses on repurposing GE37 blade segments through a multi-phase study involving material testing, structural experiments, finite element modeling, and full-scale prototype construction. Mechanical testing of spar cap specimens from DWTBs revealed strong residual properties, including 90 ksi tensile and 54 ksi compressive strength in the longitudinal direction. Full-scale bending tests on 25-ft blade segments were conducted in edgewise and flapwise orientations. Edgewise tests showed peak loads over 80 kips, stiffness of 48.6 kip/in, and energy absorption exceeding 150 kip-in. Flapwise tests exhibited ductile behavior with a peak load of 33 kip. Key failure modes included shell buckling, spar cap delamination, and adhesive failure. Finite element models were developed in ABAQUS using orthotropic layups, Hashin damage criteria, and cohesive zone modeling to simulate experimental behavior and performance of DWTB Overhead Sign Structure. The models were calibrated and validated against experimental data, demonstrating strong agreement in stiffness, load-deflection behavior, and damage progression. Under extreme wind loads of 140 mph specified by the AASHTO LRFD, the displacements and failure indices remained within acceptable safety thresholds, confirming the structural adequacy of the DWTB OSS. A full-scale DWTB OSS prototype was designed, fabricated, and installed using DWTB segments. Compared to conventional steel OSS, the repurposed structure achieved over 65% reduction in embodied energy and greenhouse gas emissions, with a total of 248 metric tons CO₂ emission reduction per structure. Material costs were reduced by 73%, driven by low-cost blade procurement and minimal fabrication. This study delivers a validated framework for integrating repurposed DWTBs into civil infrastructure, demonstrating feasibility, environmental benefit, and economic advantage. It advances sustainable infrastructure practices and supports the transition to circular composite reuse in the built environment
Straight to the Workforce: An Early Exploration of Economic Outcomes of Youth with a Career-Focused High School Credential in Texas
No full textAcross the globe, as countries implement policies and programs to increase college enrollment of youth to increase their workforce outcomes, a recently implemented education policy in Texas instead centers the student in selecting career pathways right out of high school. This paper explores the relationship between career-focused graduation plans and workforce outcomes of the 40% of Texas public school youth who do not continue into higher education. Through access to a statewide, individual-level data repository, this research produces a thorough descriptive analysis of the workforce outcomes of high school graduates who do not continue into higher education and estimates relationships between workforce outcomes and career-focused high school graduation plans. Our findings indicate that early in their implementation, career-focused graduation plans demonstrate no relationship to workforce outcomes for high school graduates who do not continue into higher education. We further found a declining trend in workforce participation for youth with only a high school credential. In conclusion, we recommend revising current graduation pathways to reinstate the requirement for higher-level mathematics courses across all graduation plans, while also ensuring that every student has access to these advanced math opportunities during high school
Imine Photochemistry: Selective and Mild C-H Functionalization and Polystyrene Upcycling
No full textNitrogen-containing compounds are prevalent in natural products, bioactive molecules, and pharmaceuticals. Among them, basic amines are particularly important medicinal targets in medicinal chemistry, playing a vital role in drug discovery and development. Although amination methodologies are comprehensively studied, many suffer from drawbacks and limitations. Therefore, innovative methodologies for synthesizing nitrogen-containing compounds are strongly needed. Imine, bearing a carbon-nitrogen double bond, is valuable intermediates in organic synthesis, especially in functional group transformations and carbon-carbon bond formation. In my research, imine was used as key intermediates to synthesize basic amines across three different projects. In the first project, we developed selective intermolecular C-H alkylation via triplet state of imine. This metal-free transformation requires no protecting group and leaving group, operates under mild conditions, and delivers the primary amine directly. It also has a broad substrate scope, and most of them give high yields. Additionally, this method can be applied to the inactive sp3 C-H bonds and tolerate various functional groups. The mechanism of the reaction was proposed and was supported by various mechanistic experiments. In the second project. We discovered that a stable phenyl acyl amide fragments under the black LED, generating N-H imine in situ. This imine can subsequently react with the same C-H donors mentioned in the first project. This cascade reaction involving aza-Norrish Type II fragmentation and photoalkylation delivers basic amine as the final product. This approach addressed the instability of N-H imine encountered in the first project and offered a new route for in situ imine generation. In the third project, our group developed a simple sp3 C-H imination under mild and metal-free conditions in recent years, which showed high efficiency for benzylic position. Therefore, we modified this methodology to make it more appropriate for polymer and successfully installed the primary amine onto the backbone of polystyrene. This modification significantly increased the hydrophilicity without deterioration of the molecular weight and thermal properties of the polymer. It also provides a handle for further covalent modification. This project offers a novel strategy for polymer functionalization and upcycling
Towards Energy Justice: How is Policy Feedback Shaping Energy Equity and Climate Policies in the U.S.?
No full textWith the transformation of energy systems and the impact of climate change, scholars and policymakers are seeking to address the normative questions surrounding energy equity and the future of climate policymaking. This dissertation uses theories of Policy Feedback, Social Construction of Target Populations, Administrative Burden, and Policy Diffusion to the nascent field of energy equity and climate policymaking. Through three papers, it examines the policy feedback effects of current energy policies and their impact on social, energy, and climate equity and justice. The papers evaluate (a) the differences in experiences of energy insecurity and policy feedback effects of means-tested home energy assistance programs that across race groups, (b) the role of administrative burden in shaping program access and policy feedback, and (c) and the policy feedback of energy policies on the diffusion of solar incentives for low- and moderate-income (LMI) households. The results highlight that the energy insecurity challenges experienced by low-income and racial minorities are exacerbated by energy assistance programs that have been designed to alleviate these issues. The feedback effects worsen the marginalization of these groups and encumber their ability to participate in the energy transition. Concurrently, the feedback effects of policies that aid the diffusion of LMI solar incentives can offer valuable insights and accumulated policy experience to address these systemic inequities. Together, these results underscore the urgent need for comprehensive policy reform to address the systemic barriers that perpetuate energy inequities and identify the low-hanging opportunities for policy reform and the development of new policies to advance energy justice
Essays on Knowledge Management in the Age of AI
No full textKnowledge Management (KM) research in Information Systems (IS) has evolved over the last thirty years. Being a fundamental area of the IS field, this research stream has helped organizations to understand and manage their knowledge resources. Although the frequency of KM research in IS has declined in the last few years, the recent advances in Artificial Intelligence (AI), particularly the advent of generative tools like Generative AI (aka. GenAI), herald a new epoch in organizational KM, filled with possibilities and complexities. The remarkable capabilities of AI have ushered in novel avenues for bolstering KM practices, especially knowledge transfer, across diverse sectors. By influencing every facet of KM processes, AI facilitates the generation of new knowledge and a seamless transfer of codified knowledge. With the emergence of self-learning algorithms, AI has facilitated the transfer of tacit knowledge as well, which was previously deemed impossible. By taking a historical reflection on previous KM research, my dissertation research provides two major insights- how traditional KM can guide future AI-led KM and how the future AI-led KM will change traditional KM research and practice. My dissertation research is designed to create three studies. Based on a comprehensive literature review of KM research in IS, the first study provides a holistic view of diversified KM areas and an assessment of to-date KM research. Based on a concept-centric analysis, this review explores and summarizes the KM literature in IS, determines the degree to which KM areas have progressed, provides a collective sense of the entire body of work, recognizes the current limitations, and identifies future research directions. By informing future researchers about what has been done to date in the KM topic in IS, this review paper provides a necessary resource for researchers working on KM and framing for future endeavors. Founded on the review of the first study, the second study develops a knowledge transfer framework illustrating different outcomes of transferring knowledge with different levels of tacitness. The current IS studies on knowledge transfer largely overlooked how the tacitness of knowledge and features of knowledge transfer mechanisms influence knowledge transfer outcomes as they interact with each other. To address this gap, my second study offers a three-dimensional knowledge transfer framework illustrating how knowledge transfer outcomes may vary as knowledge types (e.g., explicit vs. tacit), knowledge transfer mechanisms (e.g., codification vs. personalization), and task types (e.g., cognitive vs. psychomotor) interact. Based on the framework from the second study, the third study empirically tests the effectiveness of different training tools in improving health workers' knowledge and skills. Specifically, this study examined the impact of different training tools (e.g., virtual reality and video) in improving unskilled nurses’ resuscitation knowledge and skills. Intrapartum-related events such as birth asphyxia cause the death of millions of newborn babies across the globe, especially in low and medium-income countries (LMICs). Training health workers on neonatal resuscitation can significantly lower this death rate. Results from a randomized controlled experiment, conducted in two LMICs- Kenya and Nigeria, showed that different training tools differentially impact different types of resuscitation knowledge and skills
Size Effects of Silver Nanoparticles and Magnetic Beads on Silver-Gold Galvanic Exchange in Aptamer-Based Electrochemical Assays
No full textIn this work, we investigated the influence of silver nanoparticle (AgNP) size (diameters of 20, 50, and 100 nm) and magnetic bead (MB) size (diameters from 100 to 4500 nm) on silver-gold galvanic exchange signal generation in magnetic electrochemical assays. Two conjugation strategies, including biotin-streptavidin interaction and a streptavidin-specific aptamer interaction, were compared to assess differences in binding chemistry and conjugation efficiency. Calibration studies showed that 50 nm diameter AgNPs provided the best sensitivity and galvanic exchange efficiency, yielding the lowest detection limits across both conjugation strategies. Larger AgNPs produced stronger signals but reached saturation rapidly, whereas smaller particles required higher concentrations to achieve equivalent silver content. Among MBs, 1000 nm beads consistently gave the highest galvanic exchange efficiency, offering sufficient surface area for AgNP loading while minimizing steric hindrance and electrode obstruction. These findings were confirmed by complementary electrochemical impedance spectroscopy, UV-Vis absorbance, and SEM imaging, which collectively demonstrated the strong influence of bead size on charge transfer resistance and conjugation efficiency. Overall, the combination of 50 nm AgNPs with 1000 nm MBs emerged as the optimal configuration, providing improved sensitivity and reproducibility. We believe these results offer valuable design guidelines for the development of next-generation aptamer-based electrochemical biosensors for biomarker detection
AI-Powered Advisory Platforms for Sustainable Marketing Innovation in SMEs: Empirical Evidence from Underserved U.S. Markets
No full textSmall and medium-sized enterprises (SMEs) drive economic growth but face barriers in adopting AI for creative digital marketing, particularly in underserved U.S. markets. This study investigates an AI-driven unified advisory platform to enable strategic digital marketing in these communities. Integrating modules such as MarketRadar (customer insights, benchmarking) with StrategicCoaching and ComplianceTools, it supports data-driven campaign design, pricing, and engagement. Using mixed methods, we interviewed 13 SME owners/managers in Houston&rsquo;s underserved neighborhoods and surveyed 172 platform users across three U.S. states. Results show that SMEs using multiple modules achieved higher customer acquisition and revenue than standalone users, with qualitative insights revealing creative repositioning and refinement despite limited budgets. Trust elements like PeerBenchmarks and ComplianceAlerts boosted uptake. Our study advances digital marketing literature by evidencing how AI platforms and cross-module collaboration catalyze innovation, decision-making, and sustainable growth in U.S. contexts, with caution for broader extrapolation. It offers recommendations for policymakers and SaaS providers on inclusive transformation in resource-constrained settings
Stabilizing the Localized Surface Plasmon Resonance (LSPR) of Citrate-Synthesized Metal Nanoparticles in Organic Solvents
No full textGold&ndash;silver nanoshells (GS-NSs) are hollow spherical nanoparticles with an alloyed Ag-Au shell. GS-NSs exhibit a tunable localized surface plasmon resonance (LSPR) in the visible to near-IR wavelengths as a function of composition and shell thickness and offer greater stability across pH ranges compared to other metal nanoparticles. These properties make GS-NSs promising materials for diagnostics, photothermal therapy, and photocatalysis. However, current research has explored GS-NSs only in aqueous systems, since they immediately aggregate in other solvents, limiting their utility. This paper provides an in-depth study of the choice and effect of non-thiol ligands on the stability and phase-transfer of GS-NSs from aqueous to non-aqueous solvents, such as ethylene glycol, tetrahydrofuran, dichloromethane, and toluene. Ligand exchange for functionalization of GS-NSs was performed with Triton X-100 (TX100), sodium stearate (NaSt), polyvinylpyrrolidone (PVP), and hydroxypropyl cellulose (HPC), prior to phase-transfer. The nanoparticles were phase-transferred to the non-aqueous solvents, and the stability of the colloids in the various solvents before and after functionalization was recorded with UV&ndash;visible spectroscopy, dynamic light scattering (DLS), zeta potential (&zeta;), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The study was also extended to include silver nanoparticles (AgNPs) and gold nanoparticles (AuNPs) to evaluate broad-range applicability. Among the ligands studied, HPC functionalization demonstrated the widest range of phase-transfer stability across 21 days for all three particle systems studied. UV&ndash;vis spectroscopy demonstrated sustained LSPR integrity after HPC functionalization in EG, THF, and DCM. SEM, TEM, and hydrodynamic size measurements by DLS further confirmed no aggregation in EG, THF, and DCM but suggested possible twinning or clustering in the solution. Overall, this work successfully identified non-toxic alternatives to expand the LSPR stability of citrate-synthesized metal nanoparticles in organic solvents
The NuMI Neutrino Flux Prediction at ICARUS
No full textThe Deep Underground Neutrino Experiment (DUNE) is a next-generation long-baseline neutrino oscillation experiment seeking to probe fundamental symmetries within the structure of the Pontecorvo-Maki-Nakagawa-Sakata (PMNS) mixing matrix, and perform precision measurements its parameters including the neutrino mass ordering via the sign of ∆m²₃₁, and the charge-parity violating phase, δᴄᴘ. To make these measurements with high precision, DUNE will require external ν-Ar scattering cross section data as a crucial input to the oscillation fit. Imaging Cosmic And Rare Underground Signals (ICARUS) is a 476 t liquid argon neutrino detector located at Fermi National Accelerator Laboratory (FNAL) where it is serving as the far detector for the Short-Baseline Neutrino (SBN) program along the Booster Neutrino Beam (BNB) axis. ICARUS additionally lies 795 m downstream and 100.1 mrad off-axis of the Neutrinos at the Main Injector (NuMI) neutrino beam. From this position, ICARUS is exposed to a large flux of NuMI (anti-)electron and (anti-)muon neutrinos, and poses a unique opportunity to provide high-statistics measurements of quasi-elastic and single pion-production cross sections for four neutrino flavors (νᵤ, νₑ, ν̅ᵤ, ν̅ₑ). This dissertation is centered around accurately characterizing the models and estimating their precision for use in making these measurements. This includes identifying major sources of uncertainty in the models such that they can be properly propagated to the cross section measurements. Specifically, this work focused on the model of the NuMI beamline and its impact on the neutrino fluxes, but also delved into the detector response model and its impact on reconstructed observables in the detector. Significant efforts were made to improve the characterization to enhance precision and thus reduce the level of propagated uncertainty. In particular, the NuMI flux was determined to be composed of 57% νᵤ, 38% ν̅ᵤ, 3% νₑ, and 2% ν̅ₑ while the horns are operating in the positive-particle focusing configuration. The total uncertainty on the νᵤ + ν̅ᵤ (νₑ + ν̅ₑ) flux while operating in the forward horn operating mode was determined to be 10.84% (9.04%). Compared to the on-axis flux, mesons that eventually decay to neutrinos more frequently reinteract within the NuMI structure, resulting in elevated uncertainty as these processes are not well-constrained by existing hadron interaction cross section measurements. Covariance matrices were calculated to propagate the flux uncertainty characterization to NuMI analyses