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Single atoms of platinum group metals on CeO2 represent a potential approach to lower precious metal requirements for automobile exhaust treatment catalysts. Here we show the dynamic evolution of two types of single-atom Pt (Pt1) on CeO2, i.e., adsorbed Pt1 in Pt/CeO2 and square planar Pt1 in PtATCeO2, fabricated at 500 °C and by atom-trapping method at 800 °C, respectively. Adsorbed Pt1 in Pt/CeO2 is mobile with the in situ formation of few-atom Pt clusters during CO oxidation, contributing to high reactivity with near-zero reaction order in CO. In contrast, square planar Pt1 in PtATCeO2 is strongly anchored to the support during CO oxidation leading to relatively low reactivity with a positive reaction order in CO. Reduction of both Pt/CeO2 and PtATCeO2 in CO transforms Pt1 to Pt nanoparticles. However, both catalysts retain the memory of their initial Pt1 state after reoxidative treatments, which illustrates the importance of the initial single-atom structure in practical applications. The use of single atoms of platinum group metals on CeO2 is a promising approach to reduce precious metal requirements for automobile exhaust treatment catalysts. Here, the authors discovered that by manipulating the calcination temperatures, they could control the configuration of Pt1 on the CeO2 surface, leading to differences in CO oxidation activity. [ABSTRACT FROM AUTHOR]

In path analysis, using composite scores without adjustment for measurement unreliability and violations of factorial invariance across groups lead to biased estimates of path coefficients. Although joint modeling of measurement and structural models can theoretically yield consistent structural association estimates, estimating a model with many variables is often impractical in small samples. A viable alternative is two-stage path analysis (2S-PA), where researchers first obtain factor scores and the corresponding individual-specific reliability coefficients, and then use those factor scores to analyze structural associations while accounting for their unreliability. The current paper extends 2S-PA to also account for partial invariance. Two simulation studies show that 2S-PA outperforms joint modeling in terms of model convergence, the efficiency of structural parameter estimation, and confidence interval coverage, especially in small samples and with categorical indicators. We illustrate 2S-PA by reanalyzing data from a multiethnic study that predicts drinking problems using college-related alcohol beliefs. [ABSTRACT FROM AUTHOR]

Effective therapy of infection impaired tissue defects has long been an important but challenging topic, and alternative antibiotic‐free solutions are greatly demanded to tackle bacterial infections and promote tissue repair. Herein, the use of supercharged gold nanoclusters (AuNCs) with enhanced enzyme mimic activity as novel interface modulator of bioactive glass nanoparticles (BGN) for infected wound treatment is reported. The supercharged AuNCs exhibit extraordinary affinity toward BGN, leading to the robust immobilization of AuNCs on BGN (BGN‐AuNCs). Functional AuNCs endow BGN with superior peroxidase‐like activity for catalytic antibacterial action, which can kill bacteria with a concentration down to 75 µg mL−1 within 6 h due to the production of highly toxic ·OH. Moreover, expression level of COL‐1, TGF‐β, and FGF‐2 in fibroblasts is actively up‐regulated to 2.9, 3.1, and 1.6 times higher than that of control group due to the positive effect of BGN‐AuNCs on cell proliferation. Meanwhile, intrinsic photoluminescent property of AuNCs enables the direct visualization of BGN at both in vitro and in vivo levels for potentially bioimaging‐guided therapy. Further in vivo results demonstrate that BGN‐AuNCs hold enormous promise for infectious disease therapy and pro‐regeneration, and the proposed supercharged interface engineering strategy is attractive for developing advanced functional nanomedicines. [ABSTRACT FROM AUTHOR]