HyperAntivirus

HyperAntivirus

http://www.hyperantivirus.com/?id=YEEE1AAdbYAdfEx

Neanderthal Man

The hottest thing in human evolution studies right now is DNA extracted from fossils of Neandertals and other long-gone populations. Pääbo, the dean of ancient-gene research, explains in his book how it all began when he bought a piece of calf liver at a supermarket in 1981.

In those days, DNA had been successfully pulled only from living animals. Pääbo modified the methods to extract genetic material from the dead calf’s liver, which had been heated to make it hard and dry like an Egyptian mummy. Pääbo then retrieved human DNA from an actual Egyptian mummy. A high-profile journal published his findings.

After that auspicious start, the Swedish scientist recounts how he came to run the world’s first laboratory studying ancient DNA. A recurring theme in the book concerns Pääbo’s obsessive push to eliminate sources of contamination in ancient DNA, especially modern human DNA transmitted by scientists who handle (and in one case, licked) fossils.

Pääbo describes professional tensions that flared in 2006 when his team chose a technique to sequence the Neandertal genome. Researchers who had developed an early method of extracting DNA from fossils lost out to developers of a simpler but more powerful procedure. Feelings were hurt. The leader of the snubbed research group became a competitor of Pääbo’s for Neandertal bones and for bones from Neandertal relatives called Denisovans.

Aside from such behind-the-scenes dramas, Pääbo provides a fascinating look at how his personal life 

100 Science Expermences

Creature power

Sometime in the future: A patient leaves the hospital with a new pacemaker implanted next to her heart to steady its beat. Her older brother, who went through the same procedure a few years earlier, will soon need another major surgery to replace his pacemaker’s batteries. But she won’t. Her device can generate its own electricity indefinitely with sugar and oxygen harvested from her bloodstream.

Scientists are racing to perfect the technology that could make this possible. If they succeed, these “biological fuel cells” could usher in a new wave of medical devices smaller and more versatile than today’s batteries allow.

Showers that reuse your soapy water.

The OrbSys shower claims to save up to 90 percent of the water you'd normally use to get yourself clean by catching and sending it right back to you. Don't worry -- the dirty, soapy water goes through a purification process first, before it emerges as drinking quality at a higher-than-average pressure. And because the used water only needs to be reheated slightly, the shower saves up to 80 percent in energy, or about $1,350 per year from the average utility bill. Swedish tech company Orbital Systems developed the shower with NASA's Johnson Space Center, having been inspired by the designs used in space missions, where fresh water is obviously limited.

Firefighting Robot Paints 3D Image for Rescuers

Recent headlines regarding autonomous robots suggest that smart machines have a license to kill. But a new project from engineers at the University of California, San Diego suggests a different reality.

The UC engineers have built a pack of tiny autonomous robots that could help save the lives of both fire victims and firefighters.

These lifesaving robots, which look a lot like small Segways, were designed for mobility, agility and reconnaissance. As the first to enter burning buildings, they can serve as scouts for firefighters arriving at the scene of an emergency.

The robots are equipped with infrared and red-green-blue (RGB) cameras, which they use to record temperatures, detect volatile gases and check for structural integrity - all while also searching for victims.

Using on-board software systems, the bots turn the information they gather into 3D maps, which can be viewed by firefighters in real time.

The robots' Segway-like structure, which includes an actuated center leg, even lets them climb stairs and overcome large obstacles. When working collaboratively, the bots can provide firefighters with a highly detailed map of an entire structure.

"These robot scouts will be small, inexpensive, agile and autonomous," said Thomas Bewley, professor of mechanical engineering at the Jacobs School of Engineering at UC San Diego.

Firefighters arriving at the scene of a fire have a thousand things to do. To be useful, the robotic scouts need to work like well-trained hunting dogs, dispatching quickly and working together to achieve complex goals while making all necessary low-level decisions themselves along the way to get the job done."

And this pack of robots isn't the only machine helping first responders. A research team at the University of Sheffield in the U.K. recently developed a "tactile helmet" that lets firefighters sense what's going on around them, even in total darkness.

And the European Space Agency recently funded the development of an autonomous reconnaissance robot designed to gather sensory information about hazardous disaster scenes. [See also: Killer Robots Condemned in New UN Report].

Your Cellphone Could Be a Sonar Device

Submarines have used sonar for decades. Bats and dolphins have used it for millions of years. And thanks to a little math, humans could soon be echolocating with their mobile phones.

At the École Polytechnique Fédérale de Lausanne (EPFL), in Switzerland, experts in signal processing discovered a mathematical technique that allows ordinary microphones to "see" the shape of a room by picking up ultrasonic pulses as they bounce off the walls. The work was published in this week's edition of the journal Proceedings of the National Academy of Sciences (PNAS).

Microphone echolocation is harder than it sounds. Ambient noise in any room interferes with the sounds used to locate the walls, and the echoes sometimes bounce more than once. There is also the added challenge of figuring out which echoes are bouncing off which wall. [See also: "How Bats Stay on Target: Bio Sonar"]

Bats have had millions of years to evolve specialized neural circuits to fine-tune their echolocation abilities, said Ivan Dokmanic, a doctoral researcher and lead author of the PNAS paper. He added that humans can echolocate too, though not as precisely. (Some blind people have demonstrated this ability.)

One reason echolocation is easier for bats and humans than it is for computers is that bats and humans have skulls that filter the sound. Tracking where a sound originates is easier for humans because people's two ears hear slightly different things. This allows humans to pinpoint the origin of a sound.

To enable echolocation in mobile devices, Dokmanic investigated the math behind echolocation. What he found was that it's possible to treat the echoes of sounds emitted by a speaker as sources, rather than as waves bouncing off of something.

It's kind of like what happens when you look into mirror: Your eyes see a reflection, but there's the illusion that there's another person who looks just like you standing at precisely the same distance from the mirror.

That's what Dokmanic did with sound. He assumed that each echo was a source, and created a kind of grid, called a matrix, of distances. Using some advanced math, he was then able to create an algorithm that could group the echoes in the correct way to deduce the shape of a room.

First, the team experimented with an ordinary room at the EPFL, using a set of microphones and a laptop computer to test whether the algorithm worked. It did, and their next step was to test their program in the real world. So they went to a cathedral and tested it there.

"It was really the opposite environment," Dokmanic said, adding that unlike a controlled lab setting, a cathedral has a lot of ambient noise and the space isn't perfectly square.

The algorithm worked there too, showing that the echolocationscheme could detect the cathedral's walls.

"The innovation is in the way that they process the signal to calculate the shape of the room," said Tommaso Melodia, an associate professor of electrical engineering at the University at Buffalo who was not involved in the study.  

Martin Vetterli, professor of communications systems at EPFL and a co-author of the paper, said that mobile phones could be used to locate people more precisely. One problem with getting anyone's precise location on the phone is that only certain frequencies penetrate building walls, so GPS signals are sometimes useless.

Moreover, GPS is not always precise — if there's a lot of interference,it's not uncommon for a phone to say it can't locate you more precisely than within a half mile. Wi-Fi could work, but it depends on the existence of a local network.

Echolocation partly solves that problem, because it can measure the distance from where a user is standing to the walls of an individual room, and send that more precise information to tell the network exactly where that person is located. Instead of knowing where someone is within a city block, you'd be able to see that he or she is inside a room of a certain size or is surrounded by walls that give an intersection a certain shape.

One other issue is the distance between two microphones on a mobile phone. Many mobile phones have two mics —the directional mic is used when it's pressed to your head while you're on a phone call, and the other is used for canceling out the ambient noise.

The two microphones on a phone calculate the distance by triangulating – measuring the small gap between when an echo reaches each microphone. The distance between the microphones is the base of a triangle, and the time difference between echoes' time of arrival tells you the length of the other two sides.

But these two microphones usually aren't very far apart on phones, so calculating the distance to a source that's far away is harder to do.

One solution, Vetterli said, might be to use people's tendency to walk with their phones in order to help echolocate walls more accurately.

Since you can't make phones much bigger, it is simpler to have the phone take measurements from more than one spot as the user walks with it, so the base of the triangle is longer, he said.