California Institute of Technology

One-way transmission system for sound waves

While many hotel rooms, recording studios, and even some homes are built with materials to help absorb or reflect sound, mechanisms to truly control the direction of sound waves are still in their infancy. ...

Jul 26, 2011
4.6 / 5 (8) 5 | with audio podcast

From pre-gut cells to glory

For all animals, development begins with the embryo. It is here that uniform cells divide and diversify, and blueprints are laid for future structures, like skeletal and digestive systems. Although biologists ...

Jun 03, 2011
4.5 / 5 (2) 1 | with audio podcast

Learning to tolerate our microbial self

(PhysOrg.com) -- The human gut is filled with 100 trillion symbiotic bacteria—ten times more microbial cells than our own cells—representing close to one thousand different species. "And yet, if ...

Apr 21, 2011
5 / 5 (8) 0 | with audio podcast

Why do we sleep?

While we can more or less abstain from some basic biological urges—for food, drink, and sex—we can’t do the same for sleep. At some point, no matter how much espresso we drink, we just crash. ...

Feb 03, 2011
3.7 / 5 (72) 8 | with audio podcast

Voyage of the DNA Treader

Richard Feynman was right: there is plenty of room at the bottom, and the beeping, lumbering trashcans of 1950s science fiction are gradually giving way to micro-droids the size of a speck of dust . . . or even a molecule.

Dec 30, 2010
4.2 / 5 (9) 1 | with audio podcast