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The recently acquired mid-band frequency range (FR3) for 6G necessitates adopting extremely large aperture arrays (ELAAs) to leverage higher array gains and spatial multiplexing gains to compensate for larger path-losses compared to sub-6 GHz band and reduction of bandwidth availability compared to millimeter-waves, respectively. However, the nearfield of ELAAs may extend hundreds of meters depending on the aperture size and operating frequency. Hence, the planarwave based far-field channel models must be replaced by spherical-wave based near-field counterparts. To this end, we analyze the near-field performance of ELAA-based integrated sensing and communications (ISAC). This analysis captures the near-field spatial correlation, partial visibility due to spatially non-wide sense stationarities, erroneous channel estimates, an extended target, and clutter sources. A computationally-efficient conjugate precoding-based superimposed ISAC waveform is used at ELAAs. This waveform is further optimized via transmit power allocation to maximize the minimum achievable rate of the weakest communication user, while satisfying a sensing threshold for target detection. The achievable user rates and a target detector are derived. Our results demonstrate the potential of ELAA-based ISAC to improve the trade-off between the communication and sensing performance metrics. 

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.