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Alloying is an effective method for modulating metal nanoclusters to enrich their structural diversity and physicochemical properties. Recent investigations have demonstrated that polyoxometalates (POMs) can act as effective multidentate ligands for silver (Ag) nanoclusters to endow them with synergistic properties, reactivity, catalytic properties, and stability. However, the application of POMs as ligands has been confined predominantly to monometallic nanoclusters. Herein, we report a synthetic method for fabricating surface‐exposed gold (Au)−Ag alloy nanoclusters within a ring‐shaped POM ([P8W48O184]40−). Reacting an Ag nanocluster stabilized by the ring‐shaped POM with Au ions (Au+) was found to substitute several Ag atoms at the core of the nanocluster with Au atoms. The resultant {Au8Ag26} alloy nanocluster demonstrated superior photocatalytic activity and stability compared to the pristine Ag nanocluster in the aerobic oxidation of α‐terpinene under visible‐light irradiation. These findings provide fundamental insights into the formation and catalytic properties of POM‐stabilized alloy nanoclusters and advance exploration into the synthesis and applications of diverse metal nanoclusters. [ABSTRACT FROM AUTHOR]

To respond to the increasing demands for practical applications, stabilization and property modulation of metal nanoparticles have emerged as a key research subject. Herein, we present a viable protocol for preparing small metal nanoparticles (<5 nm; Ag, Pd, Pt, and Ru) via multidentate polyoxometalate (POM, [SiW9O34]10−) modification. In addition to enhancing stability, the POMs can modulate the electronic states of metal nanoparticles. Moreover, immobilization of the POM-modified metal nanoparticles on solid supports enables further tuning of the electronic states via a cooperative effect between the POMs and the supports without altering the particle size. Notably, POM-modified Pd nanoparticles on carbon support exhibited superior catalytic activity and selectivity in hydrogenation reactions in comparison with the catalyst without the POM modification. [ABSTRACT FROM AUTHOR]

Background and Aim: Changes in the number of surgeries for gastric cancer during the coronavirus disease 2019 (COVID‐19) pandemic have been reported, but data are insufficient to understand the impact at the national level. This study aimed to determine the impact of the COVID‐19 pandemic on gastric surgery in Japan. Methods: Insurance claims data registered from January 2015 to January 2021 were used. Changes in the number of endoscopic resections and gastrectomies for gastric cancer were estimated using an interrupted time‐series analysis. Results: The number of endoscopic resections significantly decreased in July 2020 (−1565; 95% confidence interval [CI]: −2022, −1108) and January 2021 (−539; 95% CI: −970, −109), and the number of laparoscopic surgeries significantly decreased in July 2020 (−795; 95% CI: −1097, −492), October 2020 (−313; 95% CI: −606, −19), and January 2021 (−507; 95% CI: −935, −78). Meanwhile, the number of open gastrectomies remained unchanged, and the number of robot‐assisted gastrectomies steadily increased since their coverage by public health insurance in April 2018. Conclusions: The decreased number of endoscopic resections and laparoscopic surgeries in Japan suggests a decline in early‐stage gastric cancer diagnosis, likely due to the suspension of gastric cancer screening and diagnostic testing during the pandemic. Meanwhile, the number of open and robot‐assisted gastrectomies remained unchanged and increased, respectively, indicating that these applications were not affected by the pandemic‐related medical crisis. These findings highlight that procedures for cancer diagnosis, including screening, should still be provided during pandemics. [ABSTRACT FROM AUTHOR]