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Maintaining high conversion under the premise of high oxygenates selectivity in syngas conversion is important but a formidable challenge in Rh catalysis. Monometallic Rh catalysts provide poor oxygenate conversion efficiency, and efforts have been focused on constructing adjacent polymetallic sites; however, the one‐pass yields of C2+ oxygenates over the reported Rh‐based catalysts were mostly <20 %. In this study, we constructed a monometallic Rh catalyst encapsulated in UiO‐67 (Rh/UiO‐67) with enhanced proximity to dual‐site Rh1,2‐Rhn ensembles. Unexpectedly, this catalyst exhibited high efficacy for oxygenate synthesis from syngas, giving a high oxygenate selectivity of 72.0 % with a remarkable CO conversion of 50.4 %, and the one‐pass yield of C2+ oxygenates exceeded 25 %. The state‐of‐the‐art characterizations further revealed the spontaneous formation of an ensemble of Rh single atoms/dimers (Rh1,2) in the proximity of ultrasmall Rh clusters (Rhn) confined within the nanocavity of UiO‐67, providing adjacent Rh+‐Rh0 dual sites dynamically during the reaction that promote the relay of the undissociated CHO species to the CHx species. Thus, our results open a new route for designing highly efficient Rh catalysts for the conversion of syngas to oxygenates by precisely tuning the ensemble and proximity of the dual active sites in a confined space. [ABSTRACT FROM AUTHOR]

Background: Vitiligo is a kind of refractory, autoimmune locally, or systemically generalized depigmentation spots caused by the disappearance of melanocyte function in the skin. Acupuncture and related therapies are extensively utilized for treating vitiligo in China. The objective of this study is to succinctly encapsulate and meticulously assess the methodological and reporting caliber of systematic reviews (SRs) pertaining to acupuncture and associated therapeutic approaches, while concurrently offering an all‐encompassing body of evidence elucidating their efficacy and safety in the treatment of vitiligo. Methods: We performed an electronic literature search in eight databases to identify SRs that evaluated the efficacy of acupuncture therapy for vitiligo. The Assessment of Multiple Systematic Reviews 2 (AMSTAR 2) tool was used to evaluate the methodological and reporting quality of these SRs. The preferred reporting items for SRs and meta‐analyses were followed according to PRISMA (2020) guidelines. Additionally, the risk of bias in systematic reviews (ROBIS) was assessed to evaluate potential bias. The quality of evidence for outcome measures was evaluated using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) framework. Results: This study included 10 SRs and assessed a total of 13 outcome measures, all of which were published before June 2023. Acupuncture therapy was more effective than control conditions for the treatment of Vitiligo. The AMSTAR‐2 results indicated a critical deficiency in the methodological quality of all SRs, with items 7 and 16 demonstrating notably low quality. The reporting quality of the included SRs according to PRISMA was deemed unsatisfactory, with significant reporting flaws identified in the areas of Protocol and registration, Risk of bias across studies, Study selection, and Limitations. According to the ROBIS assessment, 5 out of the total number of SRs (50.00%) were found to have a high risk of bias. Out of the total of 62 outcomes evaluated using the GRADE framework, 9 outcomes (14.51%) exhibited high‐quality evidence, 20 outcomes (32.26%) demonstrated moderate‐quality evidence, 19 outcomes (30.65%) presented low‐quality evidence, while 14 outcomes (22.58%) indicated very low‐quality evidence. Conclusions: This overview shows that Acupuncture therapy was more effective than the control treatment for Vitiligo. Nevertheless, given the subpar methodological quality of the reviews, we recommend conducting studies with stricter designs, larger sample sizes, and improved methodological and reporting quality to yield more robust evidence. [ABSTRACT FROM AUTHOR]