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This work proposes a cost-effective strategy to massively synthesize high-efficiency ORR electrocatalyst. [Display omitted] • A novel type of composite Co/N C was prepared. • A potential strategy was proposed to massively synthesize ORR catalysts. • High ORR activity of Co/N C triggered by Co-N heteroatomic interface. • The high stability of Co/N C in 0.1 M KOH. The development of high-efficiency and low-cost oxygen reduction electrocatalysts have become an urgent need to push fuel cells into practical application. Herein, an effective electrocatalyst Co/N C was successfully constructed, which was derived from abundant peanut shells, obtained by doping with cobalt ions and pyrolyzing in NH 3 atmosphere. Due to the abundant Co-N active sites triggered by Co-N heteroatomic interface, the prepared electrocatalysts present excellent oxygen reduction reaction (ORR) performance with more positive half-wave potential (E 1/2 = 0.83 V), incremental limiting current density (J L = 5.45 mA cm−2), higher durability and stronger resistance to methanol, which is superior to that of Pt/C (E 1/2 = 0.81 V and J L = 5.19 mA cm−2). This work proposes a potential strategy to synthesize efficient ORR electrocatalysts to instead of Pt-based catalysts. [ABSTRACT FROM AUTHOR]

Abstract The aim of this study was to confirm the effects of ginsenoside Rb1 on neural cell apoptosis in the spinal cord of rats with spinal cord ischemia-reperfusion injury (SCII) and to explore its potential mechanisms. A total of 100 healthy adult Sprague-Dawley (SD) rats were randomly divided into four groups: normal control (n = 10), sham-operated (n = 10), SCII model (n = 40), and ginsenoside Rb1-treated groups (n = 40). Basso, Beattie, Bresnahan (BBB) scale was used to examine rat hindlimb locomotor function. Nissl and Tunnel staining were used to observe neural cell injury and apoptosis, respectively, in the spinal cord of rats with SCII. Immunofluorescence staining was performed to detect the expression of Bax and Bcl-2. The levels of caspase-3 and phosphorylated Ask-1 (p-Ask-1) were detected by western blotting. Ginsenoside Rb1 prevented neural cell apoptosis in the spinal cord and improved hindlimb locomotor dysfunction of rats (P <.05). Moreover, SCII-induced upregulation of caspase-3 and p-Ask-1 levels and the Bax/Bcl-2 ratio were significantly decreased by ginsenoside Rb1 (P <.05). The protective effects of ginsenoside Rb1 on neural cells in the spinal cord of rats with SCII were mediated by the ginsenoside Rb1-induced downregulation of caspase-3 and p-Ask-1 levels and the Bax/Bcl-2 ratio. [ABSTRACT FROM AUTHOR]

Alpine meadows, typical steppes, and deserts are among the globally important rangeland types that are generally distributed along temperature and precipitation gradients. Mineral losses caused by grazing are one of the key factors that can lead to instability or even degradation of these rangeland ecosystems. We examined the concentrations of Cu, Fe, Mn, and Zn in soil, forage, and livestock dungs from diverse rangeland types in northwest China, to determine the relationships between these trace elements (TEs) concentrations and climatic factors (i.e., temperature, precipitation, and humidity), and to evaluate the potential risks of TEs deficiencies or excesses in these rangeland ecosystems. Forage Zn concentrations in forage of all three types of rangeland, and Cu concentrations in forage of the alpine meadow did not meet the growth requirements of grazing livestock. Concentrations of Cu, Fe, and Mn in forage and Fe, Mn, and Zn in livestock dungs had quadratic parabola relationships with temperature, precipitation, and humidity, but the relationships between climate factors and Cu, Fe, and Mn concentrations in soil were not significant. In addition, the abilities of the plant to absorb Cu, Fe, and Zn from soil were stronger in the typical steppe than that in the alpine meadows and desert. Also, the abilities of livestock to return TEs to soil were stronger in the alpine meadow than that in the typical steppe and desert. We derived a conceptual mode that the ratio of TE concentrations of the plant to soil and of livestock dung to forage represents the abilities of plants to absorb TEs from the soil matrix and livestock to return TEs to soil or to absorb TEs from forage, respectively. Results indicate potentially more serious risks of TEs deficiencies, especially that of Zn than previously considered in typical steppes and desert rangelands. • 1, Forage Zn concentrations in inland rangelands could not meet the growth requirement of grazing livestock. • 2, Climate factors can explain the changes of TE concentrations in forage but in soil. • 3, There is more serious risks of TE deficiencies than previously considered in typical steppes and desert. [ABSTRACT FROM AUTHOR]