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Abstract Aryl‐maleimides undergo a novel [2+4]‐photodimerization instead of the expected [2+2]‐photodimerization under both direct irradiation with visible light and under sensitized energy transfer conditions. This new excited state reactivity in aryl‐maleimides is deciphered through photochemical, photophysical, and spectroscopic studies. The stereochemistry of the photodimer depends on the type of non‐bonding interactions prevalent during photodimerization which is in turn dictated by the substituents on the maleimide ring. More importantly, the stereochemistry of the photodimer formed is complementary to the product observed under thermal conditions. 

Abstract The Winam Gulf (Kenya) is frequently impaired by cyanobacterial harmful algal blooms (cHABs) due to inadequate wastewater treatment and excess agricultural nutrient input. While phytoplankton in Lake Victoria have been characterized using morphological criteria, our aim is to identify potential toxin‐producing cyanobacteria using molecular approaches. The Gulf was sampled over two successive summer seasons, and 16S and 18S ribosomal RNA gene sequencing was performed. Additionally, key genes involved in production of cyanotoxins were examined by quantitative PCR. Bacterial communities were spatially variable, forming distinct clusters in line with regions of the Gulf. Taxa associated with diazotrophy were dominant near Homa Bay. On the eastern side, samples exhibited elevatedcyrAabundances, indicating genetic capability of cylindrospermopsin synthesis. Indeed, near the Nyando River mouth in 2022,cyrAexceeded 10 million copies L⁻¹where there were more than 6000Cylindrospermopsisspp. cells mL⁻¹. In contrast, the southwestern region had elevatedmcyEgene (microcystin synthesis) detections near Homa Bay whereMicrocystisandDolichospermumspp. were observed. These findings show that within a relatively small embayment, composition and toxin synthesis potential of cHABs can vary dramatically. This underscores the need for multifaceted management approaches and frequent cyanotoxin monitoring to reduce human health impacts. 

Abstract This study describes preservice teachers' beliefs about teaching mathematics for social justice (TMSJ) after experiencing a two‐part professional development (PD) workshop on the subject. The research question is: To what degree does a PD experience, designed by a preservice teacher, influence preservice teachers' beliefs about TMSJ? The lead author is a preservice teacher who designed and enacted two workshops for education majors at Midwest University. Results indicated that preservice teachers' beliefs were statistically significantly different, with their beliefs trending toward “more strongly agree” about TMSJ after the two‐part PD. There was also less variance in their responses to the survey after the PD compared to before it. This research offers (a) a narrative of preservice teacher‐driven PD and (b) a rich description of a PD for preservice teachers, thus adding to prior literature about in‐service teachers' outcomes. 

In the synthesis of colloidal PbS nanosheets, the supernatant of the reaction solution is reused to boost the lead conversion efficiency. It doubles the conversion efficiency of the lead precursors to the PbS nanosheets. The nanosheets synthesized by reusing the supernatant have similar morphology, nearly identical thickness, and optical properties as the original ones, confirmed by transmission electron microscopy, X‐ray diffraction, and photoluminescence spectroscopy. This method reduces the toxic Pb‐containing waste during the synthesis, a step toward the green and scalable synthesis of colloidal 2D PbS nanosheets. 

Abstract Magnetism, redness, and Fe oxides are indicators of pedoclimatic conditions. However, uncertainties with observing how Fe oxides form within soils has led to debates about relationships between magnetic mineral assemblages, temperature, and rainfall. To address these issues, Fe oxides from the equatorial tropics of Kenya were examined in Pliocene soils that developed under orbital forcing of the monsoon. Results demonstrate that with warm‐wet monsoons, ferrimagnetic production was increased and correlated with hematite concentrations, in accordance with expectations that ferrimagnetic and hematite minerals codevelop from amorphous Fe oxides. With cool‐dry monsoons, hematite concentrations increased but ferrimagnetic production decreased and decoupled from hematite development. These findings suggest that decreased rainfall rather than temperature change favored the dehydration step required to catalyze hematite enrichment within soils. This study explains Fe oxides origins under variable monsoonal climates and recognizes moisture changes in comparison to temperature as stronger controls on the production of soil‐formed hematite. 

Thermoluminescence (TL) or thermally stimulated luminescence (TSL) spectroscopy is based on liberating charge carriers from traps in the bandgap by providing enough thermal energy to overcome the potential barrier of the traps. It provides a powerful tool to measure the positions of the localized states/traps in the bandgap. Despite that, its applications in semiconductors are very limited. Herein, the basics of TL spectroscopy and the recent advances in the technique with focus on cryogenic thermally stimulated photoemission spectroscopy (C‐TSPS) which extends TL measurements to cryogenic regime and allows the detection of very low concentrations of shallow and deep localized states is discussed. One goal herein is to introduce the reader to the use of TL and C‐TSPS in the characterization of semiconductors, explaining how it can be applied and demonstrating its advantages as a powerful tool for measuring shallow donor/acceptor ionization energies in semiconductors and as a method for characterizing compensating defects. The article also discusses interesting potential applications of C‐TSPS in new research areas such as corrosion and formation of oxide layers on metal surfaces. 

Abstract Validity is a fundamental consideration of test development and test evaluation. The purpose of this study is to define and reify three key aspects of validity and validation, namely test‐score interpretation, test‐score use, and the claims supporting interpretation and use. This study employed a Delphi methodology to explore how experts in validity and validation conceptualize test‐score interpretation, use, and claims. Definitions were developed through multiple iterations of data collection and analysis. By clarifying the language used when conducting validation, validation may be more accessible to a broader audience, including but not limited to test developers, test users, and test consumers. 

Abstract Lead sulfide (PbS) quantum dots (QDs) hold great promise for solar energy conversion, yet their efficiency is compromised by a substantial Stokes shift that adversely affects their performance in photonic devices. Here, PbS QDs are integrated within single plasmonic nanocavities, significantly mitigating Stokes shifts through Purcell enhancement of their band edge emission. This approach entails bottom‐up assembly of QDs into nanoparticle‐on‐mirror structures, leading to direct emission from band‐edge excitons with radiative lifetimes suppressed below 1 ns, a drastic decrease from the 1600 ns observed in unmodified QDs. This manipulation of the Stokes shift is attributed to the increased photonic density of states within the nanocavity, which accelerates the radiative decay process and modifies exciton relaxation pathways. These results underscore the critical role of plasmonic nanocavities in modifying QD emission characteristics, offering opportunities for enhancing QD‐based device performance across a spectrum of photonic applications. 

The pandemic has created multiple changes in the lives of Americans, with growing and widespread concerns about the implications for the nation’s health and well-being. Most empirical examinations of the physical and mental health implications of the pandemic have rested on aggregate comparisons of prepandemic and pandemic indicators of health. The authors contribute to this body of work by considering continuity and change in health and well-being over time. The authors draw on respondents in a population-based sample with repeated health measures of physical health, depressive symptoms, and anxiety collected prior to the pandemic and subsequently during the pandemic. Using Sankey figures, the authors illustrate their health pathways and as a result highlight the importance of a longitudinal lens on assessments of health. The authors find health starting points are critical to understanding distribution and levels of physical and emotional health issues during the pandemic.