of a lithium-ion battery.The new virus-produced batteries have the same energy capacity and power performance as state-of-the-art rechargeable batteries being considered to power plug-in hybrid cars, and they could also be used to power a range of personal electronic devices, said Angela Belcher, the MIT materials scientist who led the research team.
The new batteries, described in the April 2 online edition of Science, could be manufactured with a cheap and environmentally benign process: The synthesis takes place at and below room temperature and requires no harmful organic solvents, and the materials that go into the battery are non-toxic.
In a traditional lithium-ion battery, lithium ions flow between a negatively charged anode, usually graphite, and the positively charged cathode, usually cobalt oxide or lithium iron phosphate. Three years ago, an MIT team led by Belcher reported that it had engineered viruses that could build an anode by coating themselves with cobalt oxide and gold and self-assembling to form a nanowire.
In the latest work, the team focused on building a highly powerful cathode to pair up with the anode, said Belcher, the Germeshausen Professor of Materials Science and Engineering and Biological Engineering. Cathodes are more difficult to build than anodes because they must be highly conducting to be a fast electrode, however, most candidate materials for cathodes are highly insulating (non-conductive).
To achieve that, the researchers, including MIT Professor Gerbrand Ceder of materials science and Associate Professor Michael Strano of chemical engineering, genetically engineered viruses that first coat themselves with iron phosphate, then grab hold of carbon nanotubes to create a network of highly conductive material.
Because the viruses recognize and bind specifically to certain materials (carbon nanotubes in this case), each iron phosphate nanowire can be electrically "wired" to conducting carbon nanotube networks. Electrons can travel along the carbon nanotube networks, percolating throughout the electrodes to the iron phosphate and transferring energy in a very short time.
The viruses are a common bacteriophage, which infect bacteria but are harmless to humans.
The team found that incorporating carbon nanotubes increases the cathode's conductivity without adding too much weight to the battery. In lab tests, batteries with the new cathode material could be charged and discharged at least 100 times without losing any capacitance. That is fewer charge cycles than currently available lithium-ion batteries, but "we expect them to be able to go much longer," Belcher said.
The prototype is packaged as a typical coin cell battery, but the technology allows for the assembly of very lightweight, flexible and conformable batteries that can take the shape of their container.
Last week, MIT President Susan Hockfield took the prototype battery to a press briefing at the White House where she and U.S. President Barack Obama spoke about the need for federal funding to advance new clean-energy technologies.
Now that the researchers have demonstrated they can wire virus batteries at the nanoscale, they intend to pursue even better batteries using materials with higher voltage and capacitance, such as manganese phosphate and nickel phosphate, said Belcher. Once that next generation is ready, the technology could go into commercial production, she said.
Lead authors of the Science paper are Yun Jung Lee and Hyunjung Yi, graduate students in materials science and engineering. Other authors are Woo-Jae Kim, postdoctoral fellow in chemical engineering; Kisuk Kang, recent MIT PhD recipient in materials science and engineering; and Dong Soo Yun, research engineer in materials science and engineering.
The research was funded by the Army Research Office Institute of the Institute of Collaborative Technologies, and the National Science Foundation through the Materials Research Science and Engineering Centers program.
Computer's Nobel Prize Announced !!!!!!!
ACM has named Barbara Liskov the recipient of the 2008 ACM A.M. Turing Award for her contributions to practical and theoretical foundations of programming language and system design, especially related to data abstraction, fault tolerance, and distributed computing.
Liskov revolutionized the programming field with groundbreaking research that underpins virtually every modern computer application for both consumers and businesses. Her achievements in programming language design have made software more reliable and easier to maintain. They are now the basis of every important programming language since 1975, including Ada, C++, Java, and C#.
Liskov heads the Programming Methodology Group in the Computer Science and Artificial Intelligence Laboratory at MIT, where she has conducted research and has been a professor since 1972.
The ACM A.M. Turing Award is ACM's most prestigious technical award. It recognizes contributions of lasting and major technical importance, and honors individuals whose work has advanced the field of computing. First presented in 1966, and named for British mathematician Alan M. Turing, the Turing Award is widely considered to be the "Nobel Prize in Computing." It carries a $250,000 prize, with financial support provided by Intel Corporation and Google Inc.
Seven years ago, Sandeep Nijsure left his home in Mumbai to study computer science at the University of North Texas. Master's degree in hand, he went to work for Microsoft. He valued his education and enjoyed the job, but he worried about his aging parents. He missed watching cricket, celebrating Hindu festivals and following the twists of Indian politics. His wife was homesick, too, and her visa didn't allow her to work.
Not long ago, Sandeep would have faced a tough choice: either go home and give up opportunities for wealth and U.S. citizenship, or stay and bide his time until his application for a green card goes through. But last year, Sandeep returned to India and landed a software development position with Amazon.com in Hyderabad. He and his wife live a few blocks from their families in a spacious, air-conditioned house. No longer at the mercy of the American employer sponsoring his visa, Sandeep can more easily determine the course of his career. "We are very happy with our move," he told me in an e-mail.
The United States has always been the country to which the world's best and brightest -- people like Sandeep -- have flocked in pursuit of education and to seek their fortunes. Over the past four decades, India and China suffered a major "brain drain" as tens of thousands of talented people made their way here, dreaming the American dream.
But burgeoning new economies abroad and flagging prospects in the United States have changed everything. And as opportunities pull immigrants home, the lumbering U.S. immigration bureaucracy helps push them away.
When I started teaching at Duke University in 2005, almost all the international students graduating from our Master of Engineering Management program said that they planned to stay in the United States for at least a few years. In the class of 2009, most of our 80 international students are buying one-way tickets home. It's the same at Harvard. Senior economics major Meijie Tang, from China, isn't even bothering to look for a job in the United States. After hearing from other students that it's "impossible" to get an H-1B visa -- the kind given to highly-skilled workers in fields such as engineering and science -- she teamed up with a classmate to start a technology company in Shanghai. Investors in China offered to put up millions even before 23-year-old Meijie and her 21-year-old colleague completed their business plan.
When smart young foreigners leave these shores, they take with them the seeds of tomorrow's innovation. Almost 25 percent of all international patent applications filed from the United States in 2006 named foreign nationals as inventors. Immigrants founded a quarter of all U.S. engineering and technology companies started between 1995 and 2005, including half of those in Silicon Valley. In 2005 alone, immigrants' businesses generated $52 billion in sales and employed 450,000 workers.
Yet rather than welcome these entrepreneurs, the U.S. government is confining many of them to a painful purgatory. As of Sept. 30, 2006, more than a million people were waiting for the 120,000 permanent-resident visas granted each year to skilled workers and their family members. No nation may claim more than 7 percent, so years may pass before immigrants from populous countries such as India and China are even considered.
Like many Indians, Girija Subramaniam is fed up. After earning a master's in electrical engineering from the University of Virginia in 1998, she joined Texas Instruments as a test engineer. She wanted to stay in the United States, applied for permanent residency in 2002 and has been trapped in immigration limbo ever since. If she so much as accepts a promotion or, heaven forbid, starts her own company, she will lose her place in line. Frustrated, she has applied for fast-track Canadian permanent residency and expects to move north of the border by the end of the year.
For the Kaufmann Foundation, I recently surveyed 1,200 Indians and Chinese who worked or studied in the United States and then returned home. Most were in their 30s, and 80 percent held master's degrees or doctorates in management, technology or science -- precisely the kind of people who could make the greatest contribution to the U.S. economy. A sizable number said that they had advanced significantly in their careers since leaving the United States. They were more optimistic about opportunities for entrepreneurship, and more than half planned to start their own businesses, if they had not done so already. Only a quarter said that they were likely to return to the United States.
Why does all this matter? Because just as the United States has relied on foreigners to underwrite its deficit, it has also depended on smart immigrants to staff its laboratories, engineering design studios and tech firms. An analysis of the 2000 Census showed that although immigrants accounted for only 12 percent of the U.S. workforce, they made up 47 percent of all scientists and engineers with doctorates. What's more, 67 percent of all those who entered the fields of science and engineering between 1995 and 2006 were immigrants. What will happen to America's competitive edge when these people go home?
Immigrants who leave the United States will launch companies, file patents and fill the intellectual coffers of other countries. Their talents will benefit nations such as India, China and Canada, not the United States. America's loss will be the world's gain.
In a rare instance of collaboration among otherwise fierce rivals, Google, Yahoo and Microsoft said Thursday that they would support a new Web standard that will allow millions of Web publishers to remove duplicate pages from their Web sites. As a result of the effort, search engines should be able to find and index more Web pages, making their search results more comprehensive.
“There is a lot of clutter on the Web and with this, publishers will be able to clean up a lot of junk,” said Matt Cutts, an engineer who heads Google’s spam fighting efforts. “I think it is going to gain traction pretty quickly.”
The problem is the following: Many Web publishers, especially those that have voluminous sites, like e-commerce companies, have multiple URLs that all point to the same page. This confuses search engines, sometimes causing them to index the same page multiple times. As much as 20 percent of URLs on the Web may be duplicates, according to some estimates.
Engineers at Google came up with a simple way for Web publishers to indicate when a URL is a duplicate, and if so, which is the principal, or “canonical,” URL that search engines should be indexing. Yahoo and Microsoft, the No. 2 and No. 3 search engines, have agreed to support the same standard.
“We are happy that everyone is going to support the same implementation,” said Nathan Buggia, a lead program manager at Microsoft. “This is a clear benefit for publishers as it gives them an opportunity to get more exposure through search engines.”
All search engines have developed technologies to detect duplicates that are more or less effective. The so-called Canonical Link Tag, as the standard is known, should make it easier for both publishers and search engines to address the problem. “It is an important step because all the search engines are coming out with it,” said Priyank Garg, director of product management for Web search at Yahoo.Bad enough that there is a growing belief among engineers and security experts that Internet security and privacy have become so maddeningly elusive that the only way to fix the problem is to start over.
What a new Internet might look like is still widely debated, but one alternative would, in effect, create a “gated community” where users would give up their anonymity and certain freedoms in return for safety. Today that is already the case for many corporate and government Internet users. As a new and more secure network becomes widely adopted, the current Internet might end up as the bad neighborhood of cyberspace. You would enter at your own risk and keep an eye over your shoulder while you were there.
“Unless we’re willing to rethink today’s Internet,” says Nick McKeown, a Stanford engineer involved in building a new Internet, “we’re just waiting for a series of public catastrophes.”
That was driven home late last year, when a malicious software program thought to have been unleashed by a criminal gang in Eastern Europe suddenly appeared after easily sidestepping the world’s best cyberdefenses. Known as Conficker, it quickly infected more than 12 million computers, ravaging everything from the computer system at a surgical ward in England to the computer networks of the French military.
Conficker remains a ticking time bomb. It now has the power to lash together those infected computers into a vast supercomputer called a botnet that can be controlled clandestinely by its creators. What comes next remains a puzzle. Conficker could be used as the world’s most powerful spam engine, perhaps to distribute software programs to trick computer users into purchasing fake antivirus protection. Or much worse. It might also be used to shut off entire sections of the Internet. But whatever happens, Conficker has demonstrated that the Internet remains highly vulnerable to a concerted attack.
“If you’re looking for a digital Pearl Harbor, we now have the Japanese ships streaming toward us on the horizon,” Rick Wesson, the chief executive of Support Intelligence, a computer consulting firm, said recently.
The Internet’s original designers never foresaw that the academic and military research network they created would one day bear the burden of carrying all the world’s communications and commerce. There was no one central control point and its designers wanted to make it possible for every network to exchange data with every other network. Little attention was given to security. Since then, there have been immense efforts to bolt on security, to little effect.
“In many respects we are probably worse off than we were 20 years ago,” said Eugene Spafford, the executive director of the Center for Education and Research in Information Assurance and Security at Purdue University and a pioneering Internet security researcher, “because all of the money has been devoted to patching the current problem rather than investing in the redesign of our infrastructure.”
In fact, many computer security researchers view the nearly two decades of efforts to patch the existing network as a Maginot Line approach to defense, a reference to France’s series of fortifications that proved ineffective during World War II. The shortcoming in focusing on such sturdy digital walls is that once they are evaded, the attacker has access to all the protected data behind them. “Hard on the outside, with a soft chewy center,” is the way many veteran computer security researchers think of such strategies.
Despite a thriving global computer security industry that is projected to reach $79 billion in revenues next year, and the fact that in 2002 Microsoft itself began an intense corporatewide effort to improve the security of its software, Internet security has continued to deteriorate globally.Even the most heavily garrisoned military networks have proved vulnerable. Last November, the United States military command in charge of both the Iraq and Afghanistan wars discovered that its computer networks had been purposely infected with software that may have permitted a devastating espionage attack.
That is why the scientists armed with federal research dollars and working in collaboration with the industry are trying to figure out the best way to start over. At Stanford, where the software protocols for original Internet were designed, researchers are creating a system to make it possible to slide a more advanced network quietly underneath today’s Internet. By the end of the summer it will be running on eight campus networks around the country.
The idea is to build a new Internet with improved security and the capabilities to support a new generation of not-yet-invented Internet applications, as well as to do some things the current Internet does poorly — such as supporting mobile users.
The Stanford Clean Slate project won’t by itself solve all the main security issues of the Internet, but it will equip software and hardware designers with a toolkit to make security features a more integral part of the network and ultimately give law enforcement officials more effective ways of tracking criminals through cyberspace. That alone may provide a deterrent.
This is not the first time a replacement has been proposed for the current Internet. For example, modern Windows and Macintosh computers already come equipped to support a new Internet protocol known as IPv6 that would fix many of the shortcomings of the current IPv4 version. However, because of cost, performance and compatibility questions it has languished.
That has not discouraged the Stanford engineers who say they are on a mission to “reinvent the Internet.” They argue that their new strategy is intended to allow new ideas to emerge in an evolutionary fashion, making it possible to move data traffic seamlessly to a new networking world. Like the existing Internet, the new network will almost certainly have no one central point of control and no one organization will run it. It is most likely to emerge as new hardware and software are built in to the router computers that run today’s network and are adopted as Internet standards.
For all those efforts, though, the real limits to computer security may lie in human nature.
The Internet’s current design virtually guarantees anonymity to its users. (As a New Yorker cartoon noted some years ago, “On the Internet, nobody knows that you’re a dog.”) But that anonymity is now the most vexing challenge for law enforcement. An Internet attacker can route a connection through many countries to hide his location, which may be from an account in an Internet cafe purchased with a stolen credit card.
“As soon as you start dealing with the public Internet, the whole notion of trust becomes a quagmire,” said Stefan Savage, an expert on computer security at the University of California, San Diego.
A more secure network is one that would almost certainly offer less anonymity and privacy. That is likely to be the great tradeoff for the designers of the next Internet. One idea, for example, would be to require the equivalent of drivers’ licenses to permit someone to connect to a public computer network. But that runs against the deeply held libertarian ethos of the Internet.
Proving identity is likely to remain remarkably difficult in a world where it is trivial to take over someone’s computer from half a world away and operate it as your own. As long as that remains true, building a completely trustable system will remain virtually impossible..jpg)
