Wednesday, April 12, 2006

Science Links!

Here's a tremendous link from Brian Witte to a story about the latest advance in bionics. Here's an excerpt:
The bionic hand system (Dextra) produced by Dr. Craelius and his colleagues uses existing nerve pathways to control individual computer-driven mechanical fingers. Dextra consists of a standard plastic socket and silicone sensor sleeve that encases an amputee's limb below the elbow. After a brief training period, operating the fingers is biomimetic, that is, it is done by normal volitional thinking, as if the user were commanding his natural fingers. Dextra relies on the fact that much of the musculo-tendon control structures that originally operated the fingers are still present and controllable by the user and can be tapped by the proper sensors. As long as the user remembers how to activate his phantom fingers, he can mentally command the new robot fingers. Thus far, users have been able to play slow piano pieces with Dextra, as demonstrated at Epcot Center for the Discover Magazine Innovation of the Year Award ceremony.

If you're speechless, you're not the only one. Here's the link to the full story:
http://tinyurl.com/lqxtg.

Then, from the NY Times, a story about molecular evolution
(http://tinyurl.com/opvln):
By reconstructing ancient genes from long-extinct animals, scientists have for the first time demonstrated the step-by-step progression of how evolution created a new piece of molecular machinery by reusing and modifying existing parts.

The researchers say the findings, published today in the journal Science, offer a counterargument to doubters of evolution who question how a progression of small changes could produce the intricate mechanisms found in living cells.

"The evolution of complexity is a longstanding issue in evolutionary biology," said Joseph W. Thornton, professor of biology at the University of Oregon and lead author of the paper. "We wanted to understand how this system evolved at the molecular level. There's no scientific controversy over whether this system evolved. The question for scientists is how it evolved, and that's what our study showed."

Here's a story about viruses building batteries. No, I'm not drunk.
WASHINGTON (Reuters) - Researchers trying to make tiny machines have turned to the power of nature, engineering a virus to attract metals and then using it to build minute wires for microscopic batteries.

The resulting nanowires can be used in minuscule lithium ion battery electrodes, which in turn would be used to power very small machines, the researchers report in Friday's issue of the journal Science.

Here's the link:
http://tinyurl.com/euxww.

Mike Cascio sent in a link to a much more detailed story about the evolution of fish into tetrapods. Here's an excerpt:
Tetrapods evolved from lobe-finned fishes between 380 and 365 million years ago. Several fossil fragments show isolated body parts in the transition from fins to legs, or gill-breathing to air-breathing, but no one fossil offered a clear snapshot of a complete transitional form.

Hoping to understand this key period better, Shubin and his colleague Ted Daeschler of the Academy of Natural Sciences in Philadelphia, together with Farish Jenkins of Harvard, began searching for fossil-bearing sediments of the right age. After five years of digging on Ellesmere Island, in the far north of Nunavut, they hit pay dirt: a collection of several fish so beautifully preserved that their skeletons were still intact. As Shubin's team studied the species they saw to their excitement that it was exactly the missing intermediate they were looking for. "We found something that really split the difference right down the middle," says Daeschler.

Here's the link to the full story:
http://tinyurl.com/gaqm2.

Finally, from Jesse Leimkuhler, three links to NASA and some incredible photography. You could avoid working for an entire afternoon just by browsing what you can find at these three links alone.
http://www.nasa.gov/mission_pages/mars/missions/mer/mer-index.html.
http://www.nasa.gov/missions/timeline/index.html.
http://www.nasa.gov/mission_pages/cassini/main/index.html.

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