I n the era of evidence-based medicine the need for guidelines should be diminishing. After all, if the evidence is so clear, why would one expect clinicians to have trouble interpreting and applying it? In reality, the evidence is not so clear. Most evidence is acquired using imperfect tools from populations who have varying degrees of similarity to the specific patient sitting in front of eac...

Deciphering how air enters the plant hydraulic transport tissues represents a major challenge to understanding plant drought responses. Using a non-invasive and cheap visualization technique applied to leaves, the spread of embolism is found to initiate in the midrib, increase with vein order, and is seemingly influenced by vein topology.

The adaptive radiation of the eye from an optical perspective has long intrigued scientists, at least from the 19th century. In a paper on the optics of the fish lens published in 1816, David Brewster, the Scottish scientist, wrote, “There is, perhaps, no subject in natural history which has excited so much attention, as the structure and functions of the eyes of animals; . . . and the natural ...

Among 10 breakthroughs that Science announced at the end of 2002 was the discovery of a photosensing (melanopsin-containing) retinal ganglion cell (RGC) and its role in entraining the circadian clock. This breakthrough exemplifies the ultimate goal of neuroscience: to understand the nervous system from molecules to behavior. Light-sensing RGCs constitute one of a dozen discrete RGC populations ...