Shigella is a Gram-negative bacterium that causes bacillary dysentery worldwide. It invades the intestinal epithelium to elicit intense inflammation and tissue damage, yet the underlying mechanisms of its host selectivity and low infectious inoculum remain perplexing. Here, we report that Shigella co-opts human α-defensin 5 (HD5), a host defense peptide important for intestinal homeostasis and innate immunity, to enhance its adhesion to and invasion of mucosal tissues. HD5 promoted Shigella infection in vitro in a structure-dependent manner. Shigella, commonly devoid of an effective host-adhesion apparatus, preferentially targeted HD5 to augment its ability to colonize the intestinal epithelium through interactions with multiple bacterial membrane proteins. HD5 exacerbated infectivity and Shigella-induced pathology in a culture of human colorectal tissues and three animal models. Our findings illuminate how Shigella exploits innate immunity by turning HD5 into a virulence factor for infection, unveiling a mechanism of action for this highly proficient human pathogen.

Recently, research on the electrocatalytic CO 2 reduction reaction (eCO 2 RR) has attracted considerable attention due to its potential to resolve environmental problems caused by CO 2 while utilizing clean energy and producing high-value-added products. Considerable theoretical research in the lab has demonstrated its feasibility and prospect. However, industrialization is mandatory to realize the economic and social value of eCO 2 RR. For industrial application of eCO 2 RR, more criteria have been proposed for eCO 2 RR research, including high current density (above 200 mA cm −2 ), high product selectivity (above 90%), and long-term stability. To fulfill these criteria, the eCO 2 RR system needs to be systematically designed and optimized. In this review, recent research on eCO 2 RR for industrial applications is summarized. The review starts with focus on potential industrial catalysts in eCO 2 RR. Next, potential industrial products are proposed in eCO 2 RR. These products, including carbon monoxide, formic acid, ethylene, and ethanol, all have high market demand, and have shown high current density and product selectivity in theoretical research. Notably, the innovative components and strategy for industrializing the eCO 2 RR system are also highlighted here, including flow cells, seawater electrolytes, solid electrolytes, and a two-step method. Finally, some instructions and possible future avenues are presented for the prospects of future industrial application of eCO 2 RR.

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Fast and reversible phase transitions in chalcogenide phase-change materials (PCMs), in particular, Ge-Sb-Te compounds, are not only of fundamental interests, but also make PCMs based random access memory (PRAM) a leading candidate for non-volatile memory and neuromorphic computing devices. To RESET the memory cell, crystalline Ge-Sb-Te has to undergo phase transitions firstly to a liquid state and then to an amorphous state, corresponding to an abrupt change in electrical resistance. In this work, we demonstrate a progressive amorphization process in GeSb2Te4 thin films under electron beam irradiation on transmission electron microscope (TEM). Melting is shown to be completely absent by the in situ TEM experiments. The progressive amorphization process resembles closely the cumulative crystallization process that accompanies a continuous change in electrical resistance. Our work suggests that if displacement forces can be implemented properly, it should be possible to emulate symmetric neuronal dynamics by using PCMs.

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