Electrocatalysts with single metal atoms as active sites have received increasing attention owing to their high atomic utilization efficiency and exotic catalytic activity and selectivity. This review aims to provide a comprehensive summary on the recent development of such single-atom electrocatalysts (SAECs) for various energy-conversion reactions. The discussion starts with an introduction of the different types of SAECs, followed by an overview of the synthetic methodologies to control the atomic dispersion of metal sites and atomically resolved characterization using state-of-the-art microscopic and spectroscopic techniques. In recognition of the extensive applications of SAECs, the electrocatalytic studies are dissected in terms of various important electrochemical reactions, including hydrogen evolution reaction (HER), oxygen evolution reaction (OER), oxygen reduction reaction (ORR), carbon dioxide reduction reaction (CO2RR), and nitrogen reduction reaction (NRR). Examples of SAECs are deliberated in each case in terms of their catalytic performance, structure−property relationships, and catalytic enhancement mechanisms. A perspective is provided at the end of each section about remaining challenges and opportunities for the development of SAECs for the targeted reaction.

The photocatalytic CO2 reduction reaction (CRR) represents a promising route for the clean utilization of stranded renewable resources, but poor selectivity resulting from the competing hydrogen evolution reaction (HER) in aqueous solution limits its practical applicability. In the present contribution a photocatalyst with hydrophobic surfaces was fabricated. It facilitates an efficient three‐phase contact of CO2 (gas), H2O (liquid), and catalyst (solid). Thus, concentrated CO2 molecules in the gas phase contact the catalyst surface directly, and can overcome the mass‐transfer limitations of CO2, inhibit the HER because of lowering proton contacts, and overall enhance the CRR. Even when loaded with platinum nanoparticles, one of the most efficient HER promotion cocatalysts, the three‐phase photocatalyst maintains a selectivity of 87.9 %. Overall, three‐phase photocatalysis provides a general and reliable method to enhance the competitiveness of the CRR.

a b s t r a c tThe interaction between disease and disease information on complex networks has facilitated an interdisciplinary research area. When a disease begins to spread in the population, the corresponding information would also be transmitted among individuals, which in turn influence the spreading pattern of the disease. In this paper, firstly, we analyze the propagation of two representative diseases ( H7N9 and Dengue fever ) in the real-world population and their corresponding information on Internet, suggesting the high correlation of the two-type dynamical processes. Secondly, inspired by empirical analyses, we propose a nonlinear model to further interpret the coupling effect based on the SIS (Susceptible-Infected-Susceptible) model. Both simulation results and theoretical analysis show that a high prevalence of epidemic will lead to a slow information decay, consequently resulting in a high infected level, which shall in turn prevent the epidemic spreading. Finally, further theoretical analysis demonstrates that a multi-outbreak phenomenon emerges via the effect of coupling dynamics, which finds good agreement with empirical results. This work may shed light on the in-depth understanding of the interplay between the dynamics of epidemic spreading and information diffusion.

This paper describes the production of syngas from photocatalytic CO2 reduction with a tunable CO/H2 ratio via adjusting the properties of CuPt alloy and the distribution of cocatalysts on TiO2 hollow spheres.

The conversion of skeletal muscle fiber from fast twitch to slow‐twitch is important for sustained and tonic contractile events, maintenance of energy homeostasis, and the alleviation of fatigue. Skeletal muscle remodeling is effectively induced by endurance or aerobic exercise, which also generates several tricarboxylic acid ( TCA ) cycle intermediates, including succinate. However, whether succinate regulates muscle fiber‐type transitions remains unclear. Here, we found that dietary succinate supplementation increased endurance exercise ability, myosin heavy chain I expression, aerobic enzyme activity, oxygen consumption, and mitochondrial biogenesis in mouse skeletal muscle. By contrast, succinate decreased lactate dehydrogenase activity, lactate production, and myosin heavy chain II b expression. Further, by using pharmacological or genetic loss‐of‐function models generated by phospholipase Cβ antagonists, SUNCR 1 global knockout, or SUNCR 1 gastrocnemius‐specific knockdown, we found that the effects of succinate on skeletal muscle fiber‐type remodeling are mediated by SUNCR 1 and its downstream calcium/ NFAT signaling pathway. In summary, our results demonstrate succinate induces transition of skeletal muscle fiber via SUNCR 1 signaling pathway. These findings suggest the potential beneficial use of succinate‐based compounds in both athletic and sedentary populations.

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ObjectivesWe evaluated the association between BMI and body weight perception in a sample of children and adolescents.MethodsA cross-sectional school-based study was conducted among 7–18 year-olds (N = 9727) from 4 districts in Jilin City, China. We calculated BMI from measured weight and height and assessed body weight perception using a single questionnaire item. We analyzed these data using SPSS version 20.0.ResultsApproximately 19.8% of these youth perceived themselves as underweight, 57.8% as normal weight, and 22.4% as overweight. In reality, 4.9% were underweight, 64.3% were normal weight, and 30.8% were overweight. Furthermore, approximately 66.4% of these Chinese youth correctly perceived their body image, 28.2% underestimated their true body image, and 5.4% overestimated their weight status. Girls were more likely than boys to overestimate their weight (χ2 = 135.4, p < 0.05). Adolescents 13–18 years old were more likely than children 7–12 years old to overestimate their weight (χ2 = 248.4, p < 0.05). Senior high school students were the most likely to overestimate their weight (χ2 = 297.6, p < 0.05). Kappa tests revealed significant differences in consistency analysis of BMI and body weight perception (Kappa = 0.352, p < 0.05). Kappa < 0.4, the consistency of BMI and body weight perception was poor.ConclusionsA mismatch existed between BMI and body weight perception among these children and adolescents. Thus, schools and parents should take steps to help them improve weight management and overall health awareness.

Electroreduction of carbon monoxide (CO) possesses great potential for achieving the renewable synthesis of hydrocarbon chemicals from CO2. We report here selective reduction of CO to acetate using Cu–Pd bimetallic electrocatalysts. High activity and selectivity are demonstrated for CO-to-acetate conversion with >200 mA/cm2 in geometric current density and >65% in Faradaic efficiency (FE). An asymmetrical C–C coupling mechanism is proposed to explain the composition-dependent catalytic performance and high selectivity toward acetate. This mechanism is supported by the computationally predicted shift of the *CO adsorption from the top-site configuration on Cu (or Cu-rich) surfaces to the bridge sites of Cu–Pd bimetallic surfaces, which is also associated with the reduction of the CO hydrogenation barrier. Further kinetic analysis of the reaction order with respect to CO and Tafel slope supports a reaction pathway with *CO–*CHO recombination following a CO hydrogenation step, which could account for the electroreduction of CO to acetate on the Cu–Pd bimetallic catalysts. Our work highlights how heteroatomic alloy surfaces can be tailored to enable distinct reaction pathways and achieve advanced catalytic performance beyond monometallic catalysts.