Saturday, December 22, 2007

For a Few Bucks: Your Genome

I am intrigued by the new companies that will read your DNA for $1,000. I was first interested in 23andme - a web-based place that describes the process in a very user friendly way. A company just covered in Scientific American is deCODE's deCODEme. The story says: deCODE Genetics has launched a new service that, for a mere $985, will take your FedExed cheek swab and scan the enclosed DNA for a sprinkling of genetic variations linked with 20 or so diseases, as well as ancestry and physical traits such as eye color (in case you don't have a mirror handy). Not quite ushering in the eagerly awaited era of the $1,000 personal genome, the new service, called deCODEme, will cover less than 0.1 percent of the three billion units of the full genome, which remains a bit too pricey for most people to have sequenced—unless they are geneticist-entrepreneur J. Craig Venter. (See News Bytes of the Week—Popcorn lung leaves the factory.) An era it is, though. Hot on deCODE's heels came the Google-backed 23andMe, which offers a similar service for $999 that would cover 35 percent less of the genome, and a third company, Navigenics, is expected to launch a disease-focused scan.

Sunday, December 16, 2007

Clarke Legacy: Space Elevators?

I noticed the news today that Arthur C. Clarke is 90, and celebrated his birthday at his home in Sri Lanka. He listed three wishes: for the world to embrace cleaner energy resources, for a lasting peace in his adopted home, Sri Lanka, and for evidence of extraterrestrial beings.

I decided to check out Clarke's best-known accomplishments and was intrigued by a concept called space elevators. His novel The Fountains of Paradise, in which he first described a space elevator, he believes, ultimately will be his legacy, more so than geostationary satellites, once space elevators make space shuttles obsolete.

Wikipedia says that a space elevator is a proposed megastructure designed to transport material from a celestial body's surface into space. The term most often refers to a structure that reaches from the surface of the Earth to geosynchronous orbit (and beyond). The concept of a structure reaching to geosynchronous orbit was first conceived by Konstantin Tsiolkovsky, who proposed a compression structure, or "Tsiolkovsky tower." Most recent discussions focus on tensile structures (tethers) reaching from geosynchrous orbit to the ground. Space elevators have also sometimes been referred to as beanstalks, space bridges, space lifts, space ladders, skyhooks, orbital towers, or orbital elevators.

The most common proposal is a tether, usually in the form of a cable or ribbon, spanning from the surface near the equator to a point beyond geosynchronous orbit. As the planet rotates, the inertia at the end of the tether counteracts gravity, and also keeps the cable taut. Vehicles can then climb the tether and get in orbit without the use of rocket propulsion. Such a structure could theoretically permit delivery of cargo and people to orbit at a fraction of the cost of launching a payload into orbit, and without the substantial environmental harm caused by some rocket fuels.

Recent proposals for a space elevator are notable in their plans to incorporate carbon nanotubes into the tether design, thus providing a link between space exploration and nanotechnology.
Actual cable-scale technology is currently inadequate to build space elevators, but research is ongoing, and some people believe that technology to do this may soon exist.

Sunday, December 02, 2007

Biodiesel: Hope for the Alternative

The story in Scientific American points to work taking place to look at alternative fuels...let's see how easy it could be to switch from an oil economy!

Biodiesel may not become the airplane fuel of the future but it did prove effective enough to recently power a 1968 L-29 Czechoslovakian jet—dubbed BioJet 1—up to 17,000 feet (5,180 meters) over 37 minutes. A three minute, 15-second test the day before was the world's first flight entirely fueled by cooking oil.

"She flew and she flew just fine," says physicist Rudi Wiedemann, president and CEO of Biodiesel Solutions, Inc., whose company provided the fuel for the historic October flight: fresh canola oil refined into biodiesel. "We wanted to show that it was doable by just going out and doing it."