China’s changing food system: top-down and bottom-up forces in food system transformations

Food supplementation leads to bottom-up and top-down food-host-parasite interactions.

1. Food-prey-predator interactions may involve both 'bottom-up' and 'top-down' processes. Conventionally, food-host-parasite interactions have been seen as governed solely from the 'bottom-up', i.e. well-fed hosts can better resist parasites and so suffer less parasitism. Recent studies on diverse endo- and ecto-parasites increasingly highlight that well-fed hosts provide parasites with a bette...

An Attentional System Combining Top-Down and Bottom-Up Influences

Attention plays an important role in human processing of sensory information as a mean of focusing resources towards the most important inputs at the moment. In vision it has been argued attentional processes are crucial for dealing with the complexity of real world scenes. The problem has often been posed in terms of visual search tasks. It has been shown that both the use of prior task and co...

Manufacturing at nanoscale: Top-down, bottom-up and system engineering

The current nano-technology revolution is facing several major challenges: to manufacture nanodevices below 20 nm, to fabricate three-dimensional complex nano-structures, and to heterogeneously integrate multiple functionalities. To tackle these grand challenges, the Center for Scalable and Integrated NAno-Manufacturing (SINAM), a NSF Nanoscale Science and Engineering Center, set its goal to es...

Bottom-Up and Top-Down Tree Series Transformations

We generalize bottom-up tree transducers and top-down tree transducers to the concept of bottom-up tree series transducer and top-down tree series transducer, respectively, by allowing formal tree series as output rather than trees, where a formal tree series is a mapping from output trees to some semiring. We associate two semantics with a tree series transducer: a mapping which transforms tre...

Bottom-up, top-down