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Creators/Authors contains: "Walker, William"

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  1. University-industry partnerships (UIPs) in STEM expand opportunities for students and incorporate industry experiences into the academic enterprise. While UIPs have increased, few studies explore marginalized students’ experiences within industry settings. Our study addresses this literature gap with an emphasis on Black women in computing from HBCUs. We utilized the Role Strain and Adaptation Model for Black Women’s STEM Success and phenomenological approaches to explore challenges that many Black women encounter in UIPs—specifically structural inequities at the intersection of race and gender; macroaggressions and imposter syndrome. Implications for practice, research, and policy are discussed while noting increasingly complicated climates for diversity efforts. 
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    Free, publicly-accessible full text available March 1, 2026
  2. Given a need for scale development concerning the intersectional experiences of Black women in computing, this preliminary study seeks to design such a measure while focusing on intersectionality within three domains—structural, political, and representational. 
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    Photoinduced thiol-catalyzed hydrogen abstraction and β-scission of acyclic benzylidene acetals is demonstrated as a new route to “command-destruct” polymer thermosets. Using this approach, we show that poly(thioether acetal) networks synthesized via thiol–ene photopolymerization rapidly degrade to alkyl benzoate byproducts when triggered with light, transitioning from solid to liquid within seconds. The light-driven construction and destruction processes, accessible via distinct differences in kinetics, are readily amenable for photopatterning, additive/subtractive manufacturing and wavelength-selective applications. 
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  5. ABSTRACT Plant-derived aldehydes are constituents of essential oils that possess broad-spectrum antimicrobial activity and kill microorganisms without promoting resistance. In our previous study, we incorporated p -anisaldehyde from star anise into a polymer network called proantimicrobial networks via degradable acetals (PANDAs) and used it as a novel drug delivery platform. PANDAs released p -anisaldehyde upon a change in pH and humidity and controlled the growth of the multidrug-resistant pathogen Pseudomonas aeruginosa PAO1. In this study, we identified the cellular pathways targeted by p -anisaldehyde by generating 10,000 transposon mutants of PAO1 and screened them for hypersensitivity to p -anisaldehyde. To improve the antimicrobial efficacy of p -anisaldehyde, we combined it with epigallocatechin gallate (EGCG), a polyphenol from green tea, and demonstrated that it acts synergistically with p -anisaldehyde in killing P. aeruginosa . We then used transcriptome sequencing to profile the responses of P. aeruginosa to p -anisaldehyde, EGCG, and their combination. The exposure to p -anisaldehyde altered the expression of genes involved in modification of the cell envelope, membrane transport, drug efflux, energy metabolism, molybdenum cofactor biosynthesis, and the stress response. We also demonstrate that the addition of EGCG reversed many p -anisaldehyde-coping effects and induced oxidative stress. Our results provide insight into the antimicrobial activity of p -anisaldehyde and its interactions with EGCG and may aid in the rational identification of new synergistically acting combinations of plant metabolites. Our study also confirms the utility of the thiol-ene polymer platform for the sustained and effective delivery of hydrophobic and volatile antimicrobial compounds. IMPORTANCE Essential oils (EOs) are plant-derived products that have long been exploited for their antimicrobial activities in medicine, agriculture, and food preservation. EOs represent a promising alternative to conventional antibiotics due to their broad-range antimicrobial activity, low toxicity to human commensal bacteria, and capacity to kill microorganisms without promoting resistance. Despite the progress in the understanding of the biological activity of EOs, our understanding of many aspects of their mode of action remains inconclusive. The overarching aim of this work was to address these gaps by studying the molecular interactions between an antimicrobial plant aldehyde and the opportunistic human pathogen Pseudomonas aeruginosa . The results of this study identify the microbial genes and associated pathways involved in the response to antimicrobial phytoaldehydes and provide insights into the molecular mechanisms governing the synergistic effects of individual constituents within essential oils. 
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  6. Abstract Organogels possess characteristics that make them promising materials for enhancing our understanding of nanostructure‐diffusion relationships in gels and for use in diffusion‐centered applications including drug delivery and nanoreactor media. Unlike hydrogels, however, there are no well‐recognized techniques for measuring the fundamental diffusion parameter of diffusivity,D, in organogels. The present work establishes a technique for measuringDbased upon Fourier‐transform infrared spectroscopy. Physically crosslinked gels composed of poly[styrene‐b‐(ethylene‐butylene)‐b‐styrene] and aliphatic mineral oil are used to showcase the new technique's capability. Diffusivity of unimers—oleic acid—and reverse micelles—sodium dioctyl sulfosuccinate (AOT)—within as‐prepared and preswollen gels is quantified and resultant values are commensurate with studies of unimer and micelle diffusion in hydrogels. The case of AOT diffusion is further validated through small‐angle X‐ray scattering analysis, which is in close agreement (<20% difference). 
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