22 ago 2005

Robot lanzallamas

18 ago 2005

North America may become a 'Pleistocene Park'

Elephants, lions, cheetahs and camels could one day roam the western US under a proposal to recreate North American landscapes as they existed more than 13,000 years ago, when humans first encountered them.

The plan, proposed in a commentary in Nature and co-authored by 13 ecologists and conservation biologists, would help enrich a North American ecosystem that was left almost devoid of large mammals at the end of the Pleistocene period. It would also help preserve wildlife that faces the threat of extinction in Africa and Asia.

Between 50,000 and 10,000 years ago, 97 of 150 genera of large mammals disappeared from around the world. Although a warming climate played its part, the consensus is that over-hunting by humans probably had a significant role.

In North America, by about 13,000 years ago, humans were leaving evidence of big-game hunting using sophisticated stone tools. This hunting probably helped to drive many animals to extinction, including North American mammoths and mastodons, lions, cheetahs, camelops (a relative of the modern camel), horses and asses.

50-year plan
Although those animals are gone forever, related African and Asian species could serve as proxies, the authors say. They propose introducing the animals over 50 years, starting with horses, asses and camels, working up to elephants, and finally bringing in the big cats.

Eventually, the animals could roam in preserves hundreds of thousands of hectares in size. The best place to create this “Pleistocene Park” would be in the North American Great Plains, where the human population is relatively low and the grazing animals would have a ready supply of food.

But other conservationists think it is a bad idea. Chris Haney, a conservation biologist at Defenders of Wildlife in Washington, DC, US, says that substituting modern equivalents of extinct species will not be the same as restoring the ancient ecosystem. And he thinks it would detract from more pressing and “realistic” goals, such as restoring wolves, grizzlies, elk and other animals to their historic North American ranges. Even those reintroductions have faced bitter opposition from ranchers, farmers, and residents.

"I need to work on wolves, not mastodons," agrees Douglas Inkley, senior science adviser to the National Wildlife Federation in Reston, Virginia, US.

Obreros...

16 ago 2005

Flexible 'E-skin' Could Endow Robots with Humanlike Sense of Touch

Robots with emotions are a staple of science fiction, and a holy grail for AI researchers. But machines with another kind of feeling--a sense of touch--might be a more attainable goal for the near future. To that end, the results of a new study represent significant progress. Scientists have developed a pliable artificial skin that can sense pressure and temperature.
Last year Takao Someya of the University of Tokyo and colleagues announced that they had developed an electronic artificial skin, or E-skin, that could detect pressure. But their creation lacked the ability to sense heat and was not flexible enough to conform to such three-dimensional surfaces as robot fingers. Now Someya's team has addressed these shortcomings by embedding organic transistor-based circuits that are pressure-sensitive and organic semiconductors that are heat-sensitive in a thin plastic film. The result is a net-shaped matrix that the researchers were able to attach to the surface of an egg and that could simultaneously measure and map both pressure and temperature.

Down the road, E-skin sensitivity may well surpass that of human skin by incorporating sensors for light, humidity, strain and ultrasonic, the scientists note. A report detailing their findings was released online today by the Proceedings of the National Academy of Sciences.

15 ago 2005

Lost island 'Atlantis' may be found

An undersea island hit by a tsunami 12,000 years ago may be the source of Plato's Atlantis myth, according to a geologist and a report this month in the journal Geology.

Marc-Andre Gutscher, a geologist at University of Western Brittany in Plouzane, France, discovered a coarse-grained sedimentary deposit that could be a tsunami remnant on the submerged Spartel Island, the BBC reported. The island is 60 meters under the sea in the Gulf of Catiz, which sits between the Atlantic Ocean and the Mediterranean Sea.

The sediment dates to 12,000 years ago, or about when the philosopher Plato said Atlantis was destroyed in a tale more than 2,000 years ago. Plato said Atlantis had been demolished in a single day and night, disappearing below the sea.

Gutsher's findings lend proof to an earlier theory that Spartel inspired the legend of Altlantis. In 2001, French geologist Jacques Collina-Girard first proposed Spartel as the lost civilization.

10 ago 2005

El bolígrafo que corrige las faltas

Tres estudiantes libaneses de telecomunicaciones de la Universidad Americana de Beirut (AUB) afirman que han inventado un "bolígrafo inteligente" que corrige las faltas de ortografía. Marwa Abdel Baki, Mansur Mansur y Rosalie Saba han creado un boli "parecido a los demás", con una mini-pantalla y un diccionario electrónico. El invento les ha valido ya el Premio a la Creatividad en la Universidad.
"Lo que es revolucionario es que este lápiz puede escribir directamente sobre papel, con tinta, y no en una pantalla. El bolígrafo no está unido a un ordenador", explicó Rosalie a AFP.
El bolígrafo tiene un microprocesador dsPIC que permite transferir la escritura en papel a la mini-pantalla. El diccionario corrige entonces las faltas de ortografía poniendo cuál es la palabra correcta en la pantallita.
"La ventaja de este bolígrafo es tener un diccionario móvil muy práctico que puede ser utilizado en todas partes y por todo el mundo, sobre todo por los alumnos, los hombres de negocios y las personas que deseen aprender una nueva lengua", subraya por su parte Marwa.
"Tenemos actualmente muchas ideas para desarrollar el bolígrafo y hacerle todavía más 'inteligente'. Esperamos poder hacerle hablar e incorporar sinónimos", asegura Mansur.

7 ago 2005

'Thoughts read' via brain scans

Scientists say they have been able to monitor people's thoughts via scans of their brains.
Teams at University College London and University of California in LA could tell what images people were looking at or what sounds they were listening to.
The US team say their study proves brain scans do relate to brain cell electrical activity.
The UK team say such research might help paralysed people communicate, using a "thought-reading" computer.
In their Current Biology study, funded by the Wellcome Trust, people were shown two different images at the same time - a red stripy pattern in front of the right eye and a blue stripy pattern in front of the left.
The volunteers wore special goggles which meant each eye saw only what was put in front of it.
In that situation, the brain then switches awareness between both images, sometimes seeing one image and sometimes the other.
While people's attention switched between the two images, the researchers used fMRI (functional Magnetic Resonance Imaging) brain scanning to monitor activity in the visual cortex. It was found that focusing on the red or the blue patterns led to specific, and noticeably different, patterns of brain activity.
The fMRI scans could reliably be used to predict which of the images the volunteer was looking at, the researchers found.
Thought-provoking?
The US study, published in Science, took the same theory and applied it to a more everyday example.
They used electrodes placed inside the skull to monitor the responses of brain cells in the auditory cortex of two surgical patients as they watched a clip of "The Good, the Bad and the Ugly".
They used this data to accurately predict the fMRI signals from the brains of another 11 healthy patients who watched the clip while lying in a scanner.
Professor Itzhak Fried, the neurosurgeon who led the research, said: "We were able to tell one part of a scene from another, and we could tell one type of sound from another."
Dr John-Dylan Haynes of the UCL Institute of Neurology, who led the research, told the BBC News website: "What we need to do now is create something like speech-recognition software, and look at which parts of the brain are specifically active in a person."
He said the study's findings proved the principle that fMRI scans could "read thoughts", but he said it was a very long way from creating a machine which could read anyone's mind.
But Dr Haynes said: "We could tell from a very limited subset of possible things the person is possibly seeing."
"One day, someone will come up with a machine in a baseball cap.
"Then it really could be helpful in everyday applications."
He added: "Our study represents an important but very early stage step towards eventually building a machine that can track a person's consciousness on a second-by-second basis.
"These findings could be used to help develop or improve devices that help paralyzed people communicate through measurements of their brain activity.
But he stressed: "We are still a long way off from developing a universal mind-reading machine."
Dr Fried said: "It has been known that different areas of the temporal lobe are activated by faces, or houses.
"This UCL finding means it is not necessary to use strikingly different stimuli to tell what is activating areas of the brain."