Science & Technology
Sun, 29 Jul 2007 01:54 CDT
Landmines lurking in former combat zones could be uncovered just by listening for them.
A major obstacle to clearing mines in poorer countries is the cost. In one method, mine clearers beam a low-frequency sound wave into the ground - which gently vibrates any buried mines - along with a radar beam. When the radar beam bounces off any vibrating mines it is reflected back at a different frequency. The problem is that radar sensors cost hundreds of dollars.
Frank Werblin, Botond Roska
Sat, 28 Apr 2007 10:23 CDT
The retina processes information much more than anyone has ever imagined, sending a dozen different movies to the brain
Take care of your own eyes, don't play videogames
Frank Werblin site can be found here
At early stages of visual processing the world is divided into neurons that signal increases, and others that signal decreases in contrast at each point in visual space. Subsequent to that division in activity, these two signal paths begin to interact, and they inhibit each other at every single stage of visual processing from retina to visual cortex. This fascinating "crossover inhibition" takes many forms....feedback, feed forward, feed across. It also serves many important signal processing functions including common mode rejection, non-linearity correction, drift compensation, and noise reduction. Our lab is studying the neural circuitry that mediates this crossover interaction in an attempt to learn the secrets embodied in this treasure trove of highly sophisticated biological technology.
Sat, 28 Jul 2007 10:40 CDT
It was so faint amid the star-freckled blackness that professional star-gazer Lin Chi-sheng missed it as he photographed the heavens from Lulin Observatory, Nantou County, earlier this month.
Luckily, Lin's camera, recording time-lapse images of space through the observatory's telescope, didn't miss it -- a mighty chunk of ice and rock "a few kilometers" in diameter and hurtling toward Earth: "Asteroid C/2007-N3."
EurekAlert / American Society of Agronomy
Sat, 28 Jul 2007 07:58 CDT
Around the world, extreme climatic conditions are forcing farmers to rethink current cropping system strategies. To maximize crop production in the face of variable temperatures and precipitation, scientists say farmers may want to adopt a system in which crop sequencing decisions are based upon weather patterns and management goals each year. However, before making the change to a more adaptable cropping systems strategy, researchers say it's important to understand how short-term crop sequencing decisions affect key agronomic and environmental attributes.
From 2002-2005, a team of researchers at the USDA-ARS Northern Great Plains Research Laboratory in Mandan, North Dakota investigated crop sequencing effects of 10 crops in a region known for its variable climate. The researchers report their findings as a series of six papers in the July-August 2007 issue of Agronomy Journal. The results from the study were originally presented at the 2005 ASA-CSSA-SSSA annual meeting.
Sat, 28 Jul 2007 07:48 CDT
Russian scientist suggests a hypothesis, allowing satisfying description for mechanisms of origin and evolution of Saturn rings and, possibly, other circular structures of the Solar system.
Saturn rings could have appeared after "switching on" of giant planet's magnetic field as a result of interaction between superconducting particles of the protoplanetary cloud and magnetic field.
Fri, 27 Jul 2007 23:51 CDT
MILAN, Italy - Scientists have exhumed the Renaissance-era remains of two intellectuals who belonged to Florence's powerful Medici family court, in an effort to learn more about their lives and deaths.
The 15th century remains of humanist philosopher Giovanni Pico della Mirandola and writer Angelo Ambrogini - better known as Poliziano - were exhumed Thursday from Florence's St. Mark's Basilica. The men, who were possibly lovers, each died in 1494, and the exact cause of their deaths is unknown.
Wed, 25 Jul 2007 15:02 CDT
A computer program that learns to decode language sounds in a similar way to a baby could shed new light on how humans acquire the ability to talk, say US researchers.
It casts doubt on the idea that babies are born with an innate understanding of all possible language sounds.
Thu, 26 Jul 2007 19:58 CDT
Large quantities of ozone-depleting chemicals have been discovered in the Antarctic atmosphere by researchers from the University of Leeds, the University of East Anglia, and the British Antarctic Survey.
The team of atmospheric chemists carried out an 18-month study of the make-up of the lowest part of the earth's atmosphere on the Brunt Ice Shelf, about 20 km from the Weddell Sea. They found high concentrations of halogens - bromine and iodine oxides - which persist throughout the period when there is sunlight in Antarctica (August through May). A big surprise to the science team was the large quantities of iodine oxide, since this chemical has not been detected in the Arctic.
Thu, 26 Jul 2007 06:40 CDT
Supermassive black holes have been discovered to grow more rapidly in young galaxy clusters, according to new results from NASA's Chandra X-ray Observatory. These "fast-track" supermassive black holes can have a big influence on the galaxies and clusters that they live in. Using Chandra, scientists surveyed a sample of clusters and counted the fraction of galaxies with rapidly growing supermassive black holes, known as active galactic nuclei (or AGN). The data show, for the first time, that younger, more distant galaxy clusters contained far more AGN than older, nearby ones.
New York Times
Thu, 26 Jul 2007 03:59 CDT
For anyone stuck on a casino stool, playing hours of video poker, rest assured: humans can still beat a computer.
But computers may soon dominate on the felt-top table, as they have on the chessboard.
In a match of wits between man and machine this week, a software program running on an ordinary laptop computer fought a close match, but lost to two well-known professional human poker players.
The contest, which was billed as the "First Man-Machine Poker Championship" and which offered prize money totaling $50,000, pitted two professionals, Phil Laak and Ali Eslami, against a program written by a team of artificial intelligence researchers from the University of Alberta. They gave it a name that probably no gambler would ever choose as a nickname, Polaris.