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Nanoporous composite electrodes for lithium ion batteries were successfully fabricated by coating porous carbon with V 2 O 5 gel, and their high rate capability was demonstrated. The porous carbons prepared by using SiO 2 colloidal crystals as templates exhibited ordered three dimensionally interconnected pores. The porous carbons were immersed in V 2 O 5 sol under reduced pressure repeatedly to obtain V 2 O 5 /carbon composites. The nanoporous V 2 O 5 /carbon composites thus obtained exhibited large capacity of more than 100 mAh (gcomposite) -1 and good rate capability of 80% at 5.0 A (g-composite) -1 . The good performance is explained by electric double layer capacitance of large surface area and high rate lithium insertion to V 2 O 5 gel. According to a calculation, very high-power energy sources with 177 mAh (g-composite) -1 at 100 A (g-composite) -1 are expected by using the nanoporous composite electrodes.

The deciduous habit of northern temperate trees and shrubs provides one of the most obvious examples of convergent evolution, but how did it evolve? Hypotheses based on the fossil record posit that deciduousness evolved first in response to drought or darkness and preadapted certain lineages as cold climates spread. An alternative is that evergreens first established in freezing environments and later evolved the deciduous habit. We monitored phenological patterns of 20 species of Viburnum spanning tropical, lucidophyllous (subtropical montane and warm temperate), and cool temperate Asian forests. In lucidophyllous forests, all viburnums were evergreen plants that exhibited coordinated leaf flushes with the onset of the rainy season but varied greatly in the timing of leaf senescence. In contrast, deciduous species exhibited tight coordination of both flushing and senescence, and we found a perfect correlation between the deciduous habit and prolonged annual freezing. In contrast to previous stepwise hypotheses, a consilience of independent lines of evidence supports a lockstep model in which deciduousness evolved in situ, in parallel, and concurrent with a gradual cooling climate. A pervasive selective force combined with the elevated evolutionary accessibility of a particular response may explain the massive convergence of adaptive strategies that characterizes the world's biomes.

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