Infrastructure has become an important topic in a variety of areas of the policy debate, including energy saving and climate change. In this paper, we use an energy input-output model to evaluate the amounts of China's embodied energy use in infrastructure investment from 1992 to 2007. We also use the structure decomposition model to analyze the factors impacting the embodied energy use in infr...

In response to seasonal habitats, migratory lepidopterans, exemplified by the monarch butterfly, have evolved migration to deal with dynamic conditions. During migration, monarchs use orientation mechanisms, exploiting a time-compensated sun compass and a light-sensitive inclination magnetic compass to facilitate fall migration south. The sun compass is bidirectional with overwintering coldness...

Article history: The Paleophytic, Mesophyti Accepted 26 March 2008

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This study aims to understand how inherent ecological network structures of nestedness and modularity vary over large geographic scales with implications for community stability. Bipartite networks from previous research from 68 locations globally were analyzed. Using a meta-analysis approach, we examine relationships between the structure of 22 trophic and 46 mutualistic bipartite networks in ...

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