Catalysis using gold is emerging as an important field of research in connection with 'green' chemistry. Several hypotheses have been presented to explain the markedly high activities of Au catalysts. So far, the origin of the catalytic activities of supported Au catalysts can be assigned to the perimeter interfaces between Au nanoclusters and the support. However, the genesis of the catalytic activities of colloidal Au-based bimetallic nanoclusters is unclear. Moreover, it is still a challenge to synthesize Au-based colloidal catalysts with high activity. Here we now present the 'crown-jewel' concept (Supplementary Fig. S1) for preparation of catalytically highly Au-based colloidal catalysts. Au-Pd colloidal catalysts containing an abundance of top (vertex or corner) Au atoms were synthesized according to the strategy on a large scale. Our results indicate that the genesis of the high activity of the catalysts could be ascribed to the presence of negatively charged top Au atoms.

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Species-specific changes in insecticide susceptibility were found in Asian rice planthoppers (i.e. BPH for imidacloprid and WBPH for fipronil). Insecticide resistance in BPH against imidacloprid occurred in East Asia and Indochina, but not in the Philippines. In contrast, insecticide resistance in WBPH against fipronil occurred widely in East and South-east Asia.

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is repeatedly cited as one of the most dangerous glacial lakes in the Himalaya with a glacial lake outburst flood (GLOF) claimed to be imminent. Knowledge of lake development and its dynamics, however, is limited and forecasts of a possible outburst are not scientifically based. Nevertheless, prospects for such a catastrophe are repeatedly exaggerated, attracting alarmist mass media coverage. The paper provides an assessment of the lake expansion rates from 1956 to 2007. Stage 1 (1956Á1975), slowest: coalescence of several small supra-glacial ponds; Stage 2 (1975Á1978), a short period of most rapid expansion; Stage 3 (1978Á1997), slow: gradual expansion of single lake; and Stage 4 (1997Á2007), renewed acceleration: mainly eastward expansion into the glacier surface. The lake's water level has fallen from 5041 m to 5004 m (1964Á2006). The results show that there is no immediate danger of catastrophic outburst although the dynamics of up-glacier and down-valley lake expansion, fluctuation of lake water level, and dead-ice morphology changes should be continuously and comprehensively monitored. Alarmist prognostications based solely upon rapid areal expansion are counterproductive.

Experiments were conducted to measure the effect of feeding by the planthopper Nilaparvata lugens (Stål) on photosynthesis and the translocation of assimilates in rice plants, Oryza sativa L. We used mature japonica rice plants and applied the 13CO2 feeding method to evaluate those physiological effects. The photosynthetic rate was suppressed by N. lugens infestation, especially at the lower leaf position, with rates 30% lower than that of control plants at the booting stage. Leaf nitrogen concentration in infested plants was also lower than that in control plants. After flowering, the chlorophyll content and total plant dry weight were reduced by N. lugens. Stem and sheath dry weights were significantly reduced by N. lugens infestation, whereas panicle dry weight was not affected. Little effect was found on disruption in translocation of assimilates, even when 13CO2 was supplied to the infested leaves. Results suggested that removal of assimilates and reduction in photosynthesis by N. lugens have the greatest effect on growth and yield of rice plants as compared with the disruption in the translocation of assimilates. Plant death can occur by N. lugens infestation if the amount of energy supplied is less than that required for tissue maintenance.

The results indicated that the '3D virtual rice' has a possibility to demonstrate the differences in the structure and development between cultivars and under different environmental conditions. Future work, necessary to reflect both cultivar and environmental effects on the model performance, and to link with physiological models, is proposed in the discussion.

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