Wed Feb 13, 2008 1:43pm

 ESTCHICAGO (Reuters) - U.S. scientists have developed a microfiber fabric that generates its own electricity, making enough current to recharge a cell phone or ensure that a small MP3 music player never runs out of power.

If made into a shirt, the fabric could harness power from its wearer simply walking around or even from a slight breeze, they reported Wednesday in the journal Nature.

"The fiber-based nanogenerator would be a simple and economical way to harvest energy from the physical movement," Zhong Lin Wang of the Georgia Institute of Technology, who led the study, said in a statement.

The nanogenerator takes advantage of the semiconductive properties of zinc oxide nanowires -- tiny wires 1,000 times smaller than the width of a human hair -- embedded into the fabric. The wires are formed into pairs of microscopic brush-like structures, shaped like a baby-bottle brush.

One of the fibers in each pair is coated with gold and serves as an electrode. As the bristles brush together through a person's body movement, the wires convert the mechanical motion into electricity.

"When a nanowire bends it has an electric effect," Wang said in a telephone interview. "What the fabric does is it translates the mechanical movement of your body into electricity."

His team made the nanogenerator by first coating fibers with a polymer, and then a layer of zinc oxide. They dunked this into a warm bath of reactive solution for 12 hours. This encouraged the wires to multiply, coating the fibers.

"They automatically grow on the surface of the fiber," Wang said. "In principal, you could use any fiber that is conductive."

They added another layer of polymer to prevent the zinc oxide from being scrubbed off. And they added an ultra-thin layer of gold to some fibers, which works as a conductor.

To ensure all that friction was not just generating static electricity, the researchers conducted several tests. The fibers produced current only when both the gold and the zinc oxide bristles brushed together.

So far, Wang said the researchers had demonstrated the principle and developed a small prototype.

"Our estimates show we can have up to 80 milliwatts per square meter of this fabric. This is enough to power a little iPod or charge a cell phone battery," he said.

"What we've done is demonstrate the principle and the fundamental mechanism."

Wang said the material could be used by hikers and soldiers in the field and also to power tiny sensors used in biomedicine or environmental monitoring.

One major hurdle remains: zinc oxide degrades when wet. Wang's team is working on a process that would coat the fibers to protect the fabric in the laundry.

(Editing by Maggie Fox and Alan Elsner)

(julie.steenhuysen@reuters.com ; +1 312 408 8131))

By Maggie Fox, Health and Science Editor

WASHINGTON (Reuters) - A new detector combines a laser with a mass spectrometer to provide on-the-spot analysis that researchers hope will have applications ranging from evaluating a tumor as it is removed to quickly detecting explosives in luggage.

The laser vaporizes tiny samples that can be instantly sampled and analyzed by the spectrometer, and can be used even on living organisms, the team at George Washington University said on Thursday.

"We are talking about less than a second for an analysis," Akos Vertes, a professor of biochemistry and molecular biology at George Washington University, said in an interview.

Vertes and graduate student Peter Nemes say they have used their system to find a drug sample in urine, to detect the chemical changes that accompany color changes in a living plant leaf and to find explosives residue on a dollar bill.

The university has filed for a patent on the system, which Vertes said is the first to use a laser for such instant analysis of living tissue.

Called laser ablation electrospray ionization or LAESI, the system requires a desk-sized space in a laboratory. But smaller spectrometers and lasers could make it portable, Vertes said.

"It is still not pocket-sized," he said.

The laser burns the living tissue, vaporizing some of it and sending particles up into the air in a puff. In a process called electrospray ionization, a stream of electrically charged droplets is shot at the spot, intercepting the particles and merging with some of them to make charged droplets.

The 2002 Nobel Prize in Chemistry was awarded to John Fenn for the discovery of electrospray ionization.

PORTABLE BUNDLE

A mass spectrometer can measure any charged particle, called an ion. Vertes and Nemes say the ionizing drops can be shot from a tiny nozzle that can be bundled with a fiber-optical cable carrying the laser beam, and a small tube to carry the sample into the spectrometer to be analyzed.

"You can just go into the field and put your laser on the surface you want to analyze," Vertes said.

By taking a series of samples, the detector can analyze cell-by-cell changes.

"We hope it takes us to the biomedical field," Vertes said. "We want to go in and pop one cell open, analyze the content and go on to the next cell."

This could help biologists understand a living system, and could help surgeons as well -- for example, by analyzing tumors as they are removed. "You are already cutting the patient, so a little bit of a prick with a laser is not much more," Vertes said.

"It is very important to know when the cancerous tissue ends and the healthy tissue begins." Currently surgeons send samples to a pathology lab but this system could save precious minutes, he said.

He is trying to use it to see stem cells in the process of differentiating, or changing, into the various cell types that they can give rise to.

Current methods require scientists to look for one change at a time in each cell sample -- destroying the living cells in the process. "The power of this method is with a single shot we can look at 50 different metabolites," he said.

(Editing by Will Dunham and Eric Walsh)

Thu Nov 15, 2007 4:38pm EST

By Jon Herskovitz and Jessica Kim

SEOUL (Reuters) - South Korean university student Seong-sun is a rebel without a TV. Like other twentysomethings in tech-friendly parts of the world, Seong-sun, 27, uses his laptop to watch user-generated content and can see programming on his mobile phone.

But, in South Korea, peer-to-peer video services have exploded. His laptop is his entertainment gateway. The Internet is the distribution platform of choice and the content at his fingertips is a dizzying array of pirated TV shows and movies.

Seong-sun pays a small subscription fee to an Internet service that allows him to download thousands of movies, including Hollywood films not yet released in South Korea.

He can also receive TV shows such as "American Idol," complete with Korean subtitles, less than 24 hours after airing.

Lax enforcement of copyright laws and South Korea's high broadband penetration rate have helped fuel the popularity of these services.

"So many people do this that I'm not scared of getting caught. Everyone else thinks the same thing, too," Seong-sun said.

He asked not to have his family name used so that prosecutors would not go after him for one of their few showcase investigations.

HUGE LIBRARY

User-generated content sites such as "ipop" (www.ipop.co.kr) have clubs where users can pay by the download or pony up monthly subscription fees of about 10,000 won to 20,000 won ($11 to $22) that will let them tap into a huge library of U.S., Japanese, Chinese and Korean TV programming and movies.

One of the most popular peer-to-peer clubs, Mansal, has had nearly 50 million visitors. While many are repeaters, the total is still almost equal to the country's population.

"I like to download stuff because I don't have to wait to watch something" Seong-sun said.

The clubs make money from subscription fees and advertising. Young professionals with little time to spare and students with an abundance of time to search for material are the main clients for these services -- making cable TV and TV sets obsolete.

The clubs often obtain content from Koreans living abroad who upload movies. They also upload TV programming within hours after it airs and translate it.

The clubs have helped to make shows such as "Prison Break" and "Ugly Betty" hits first among Internet users. Cable companies later picked up local broadcasting rights.

South Korea this year stepped up penalties for those who violate copyright laws by downloading pirated material, but that has had almost no effect.

ILLEGAL DOWNLOADS

South Korea's biggest daily newspaper, the Chosun Ilbo, said in a survey earlier this year that the average movie fan watches about two movies a month in theaters and about three new releases a month via illegal downloads.

"More than half of Koreans are not aware that this is a problem," said a culture ministry official.

"But as a whole, it brings about a total of almost 1 trillion won ($1.1 billion) worth of losses to the entertainment industry a year."

Major entertainment companies have tried to get into the act by starting up services for legal downloads. Hanarotelecom, the country's No. 2 broadband provider, is offering a subscription service where users can legally download programming to their mobile phones.

Media specialists, however, only see the pirating trend getting stronger. More Koreans are used to finding their programming over the Internet and are aided by even faster download speeds to their laptops and mobile phones.

"Even if you are watching a computer or mobile phone, you still say in Korean that you are watching television," said Yoon Tae-jin, associate dean of Yonsei University's Graduate School of Communication and Art.

Yoon said young Koreans want flexibility in time and space. Downloading entertainment allows users to watch programming at a time they feel appropriate and handheld devices allow them to watch it wherever they please.

"More and more people will forget about the television set and regard the Internet as the gateway for so many types of programming and content," Yoon said.

A spokeswoman for one of South Korea's biggest TV makers, LG Electronics, said the TV set will not become obsolete but it has to evolve into a device that can tap into computer networks.

"The line between TV and PC is being blurred. Today's consumers no longer care about the conventional definition of a gadget. They just want one that fits their lifestyle," said Judy Pae of LG.

(Additional reporting by Rhee So-eui; Writing by Jon Herskovitz; Editing by Brian Moss)