Tuesday, November 04, 2008
Students in Texas are trying to create a brew that includes red wine's antiaging compound.
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| Stock still: Undergraduates are brewing beer in a Rice University lab as part of a project to create "BioBeer" that contains resveratrol, a compound found in red wine. Animals given resveratrol live longer, healthier lives. Credit: Taylor Stevenson, Rice University |
Since headlines began trumpeting the antiaging effects of red wine a couple of years ago, the traditional toast to good health has become more meaningful. But students at Rice University, in Texas, think that beer drinkers shouldn't be left out. They're trying to engineer a yeast that produces the antiaging chemical found in red wine--resveratrol--and use it to brew "BioBeer" with a health boost.
"It's not going to prevent you from getting a beer gut from drinking too much beer, or from getting cirrhosis of the liver," says Taylor Stevenson, one of six undergraduates working on the project. "But people are already drinking beer, so why not make the activity a little healthier?"
Resveratrol was discovered in red wine in the 1990s, prompting scientists to wonder if it might explain the "French paradox"--the fact that the French have a relatively low death rate from heart disease, despite a diet relatively high in saturated fat. Resveratrol is now known to extend life span in various organisms, including fish, flies, and yeast, and aging mice fed high doses of the chemical are healthier in their old age. It's not known whether resveratrol has the same effects in humans.
The BioBeer project is an entry in the International Genetically Engineered Machine (iGEM) competition being held this weekend in Cambridge, MA. The event showcases student work in the field of synthetic biology, in which researchers string together blocks of DNA--whether artificial or naturally occurring--in order to build useful new organisms from scratch.
Many of the blocks of DNA identified by synthetic-biology researchers have been recorded in the open-source Registry of Standard Biological Parts at MIT. Participants in the iGEM competition submit their own DNA blocks to the registry, and they may use parts from the registry in their projects. The BioBeer team will submit 16 blocks to the registry, Stevenson says.
Other researchers have engineered yeast to produce resveratrol under aerobic conditions, but that's of limited use, since resveratrol is deactivated by exposure to oxygen. The Rice students are trying to create a yeast that produces the chemical during fermentation. They say that the method could be used to introduce other air-sensitive pharmaceuticals into beer, which is the most popular alcoholic beverage in the United States.
"I think of it as a drinkable bioreactor," says Thomas Segall-Shapiro of the BioBeer team. "It's completely ready to go once it's brewed."
The BioBeer team has equipped yeast with two genes that code for enzymes required for resveratrol production. The first enzyme converts the amino acid tyrosine into coumaric acid, and the second turns that into resveratrol.
Resveratrol is found in low levels in hops, the raw ingredient of beer. "We're just trying to enhance something that's probably there at very low levels," says Jonathan Silberg, faculty advisor for the BioBeer project at Rice. "We're not trying to undermine wine's little niche in any way. It's a different market."
"I'm sure there would be people interested in drinking resveratrol in beer rather than wine," says Rafael de Cabo of the National Institute on Aging, who has studied the effects of resveratrol. But "you can add resveratrol directly to the beer," he says. "You don't need to make a yeast that will make resveratrol."
Inaugural Speech for the new batch at the Symbiosis BBA program 2008
© Chetan Bhagat
Good Morning everyone and thank you for giving me this chance to speak to you. This day is about you. You, who have come to this college, leaving the comfort of your homes (or in some cases discomfort), to become something in your life. I am sure you are excited. There are few days in human life when one is truly elated. The first day in college is one of them. When you were getting ready today, you felt a tingling in your stomach. What would the auditorium be like, what would the teachers be like, who are my new classmates - there is so much to be curious about. I call this excitement, the spark within you that makes you feel truly alive today. Today I am going to talk about keeping the spark shining. Or to put it another way, how to be happy most, if not all the time.
Where do these sparks start? I think we are born with them. My 3-year old twin boys have a million sparks. A little Spiderman toy can make them jump on the bed. They get thrills from creaky swings in the park. A story from daddy gets them excited. They do a daily countdown for birthday party – several months in advance – just for the day they will cut their own birthday cake.
Imagine the spark to be a lamp's flame. The first aspect is nurturing - to give your spark the fuel, continuously. The second is to guard against storms.
To nurture, always have goals. It is human nature to strive, improve and achieve full potential. In fact, that is success. It is what is possible for you. It isn't any external measure - a certain cost to company pay package, a particular car or house.
Most of us are from middle class families. To us, having material landmarks is success and rightly so. When you have grown up where money constraints force everyday choices, financial freedom is a big achievement.
But it isn't the purpose of life. If that was the case, Mr Ambani would not show up for work. Shah Rukh Khan would stay at home and not dance anymore. Steve Jobs won't be working hard to make a better iPhone, as he sold Pixar for billions of dollars already. Why do they do it? What makes them come to work everyday?
They do it because it makes them happy. They do it because it makes them feel alive. Just getting better from current levels feels good. If you study hard, you can improve your rank. If you make an effort to interact with people, you will do better in interviews. If you practice, your cricket will get better. You may also know that you cannot become Tendulkar, yet. But you can get to the next level. Striving for that next level is important.
Nature designed with a random set of genes and circumstances in which we were born. To be happy, we have to accept it and make the most of nature's design. Are you? Goals will help you do that.
I must add, don't just have career or academic goals. Set goals to give you a balanced, successful life. I use the word balanced before successful. Balanced means ensuring your health, relationships, mental peace are all in good order.
There is no point of getting a promotion on the day of your breakup. There is no fun in driving a car if your back hurts. Shopping is not enjoyable if your mind is full of tensions.
You must have read some quotes - Life is a tough race, it is a marathon or whatever. No, from what I have seen so far, life is one of those races in nursery school. Where you have to run with a marble in a spoon kept in your mouth. If the marble falls, there is no point coming first. Same with life, where health and relationships are the marble. Your striving is only worth it if there is harmony in your life. Else, you may achieve the success, but this spark, this feeling of being excited and alive, will start to die.
One last thing about nurturing the spark - don't take life seriously. One of my yoga teachers used to make students laugh during classes. One student asked him if these jokes would take away something from the yoga practice. The teacher said - don't be serious, be sincere. This quote has defined my work ever since. Whether its my writing, my job, my relationships or any of my goals. I get thousands of opinions on my writing everyday. There is heaps of praise, there is intense criticism. If I take it all seriously, how will I write? Or rather, how will I live? Life is not to be taken seriously, as we are really temporary here. We are like a pre-paid card with limited validity. If we are lucky, we may last another 50 years. And 50 years is just 2,500 weekends. Do we really need to get so worked up? It's ok, bunk a few classes, goof up a few interviews, fall in love. We are people, not programmed devices.
I've told you three things - reasonable goals, balance and not taking it too seriously that will nurture the spark. However, there are four storms in life that will threaten to completely put out the flame. These must be guarded against. These are disappointment, frustration, unfairness and loneliness of purpose.
Disappointment will come when your effort does not give you the expected return. If things don't go as planned or if you face failure. Failure is extremely difficult to handle, but those that do come out stronger. What did this failure teach me? is the question you will need to ask. You will feel miserable. You will want to quit, like I wanted to when nine publishers rejected my first book. Some IITians kill themselves over low grades – how silly is that? But that is how much failure can hurt you.
But it's life. If challenges could always be overcome, they would cease to be a challenge. And remember - if you are failing at something, that means you are at your limit or potential. And that's where you want to be.
Disappointment's cousin is frustration, the second storm. Have you ever been frustrated? It happens when things are stuck. This is especially relevant in India. From traffic jams to getting that job you deserve, sometimes things take so long that you don't know if you chose the right goal. After books, I set the goal of writing for Bollywood, as I thought they needed writers. I am called extremely lucky, but it took me five years to get close to a release.
Frustration saps excitement, and turns your initial energy into something negative, making you a bitter person. How did I deal with it? A realistic assessment of the time involved – movies take a long time to make even though they are watched quickly, seeking a certain enjoyment in the process rather than the end result – at least I was learning how to write scripts , having a side plan – I had my third book to write and even something as simple as pleasurable distractions in your life - friends, food, travel can help you overcome it. Remember, nothing is to be taken seriously. Frustration is a sign somewhere, you took it too seriously.
Unfairness - this is hardest to deal with, but unfortunately that is how our country works. People with connections, rich dads, beautiful faces, pedigree find it easier to make it – not just in Bollywood, but everywhere. And sometimes it is just plain luck. There are so few opportunities in India, so many stars need to be aligned for you to make it happen. Merit and hard work is not always linked to achievement in the short term, but the long term correlation is high, and ultimately things do work out. But realize, there will be some people luckier than you.
In fact, to have an opportunity to go to college and understand this speech in English means you are pretty darn lucky by Indian standards. Let's be grateful for what we have and get the strength to accept what we don't. I have so much love from my readers that other writers cannot even imagine it. However, I don't get literary praise. It's ok. I don't look like Aishwarya Rai, but I have two boys who I think are more beautiful than her. It's ok. Don't let unfairness kill your spark.
Finally, the last point that can kill your spark is isolation. As you grow older you will realize you are unique. When you are little, all kids want Ice cream and Spiderman. As you grow older to college, you still are a lot like your friends. But ten years later and you realize you are unique. What you want, what you believe in, what makes you feel, may be different from even the people closest to you. This can create conflict as your goals may not match with others. . And you may drop some of them. Basketball captains in college invariably stop playing basketball by the time they have their second child. They give up something that meant so much to them. They do it for their family. But in doing that, the spark dies. Never, ever make that compromise. Love yourself first, and then others.
There you go. I've told you the four thunderstorms - disappointment, frustration, unfairness and isolation. You cannot avoid them, as like the monsoon they will come into your life at regular intervals. You just need to keep the raincoat handy to not let the spark die.
I welcome you again to the most wonderful years of your life. If someone gave me the choice to go back in time, I will surely choose college. But I also hope that ten years later as well, you eyes will shine the same way as they do today. That you will Keep the Spark alive, not only through college, but through the next 2,500 weekends. And I hope not just you, but my whole country will keep that spark alive, as we really need it now more than any moment in history. And there is something cool about saying - I come from the land of a billion sparks.
A novel nanolaser could cram more data onto a hard disk.
By Prachi Patel-Predd
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| Spot light: To make a laser that focuses nanowatts of power into a 30-nanometer spot, researchers cover a semiconductor diode with an aluminum film etched with different nanoscale apertures. A scanning near-field optical-microscope image shows that the most laser light comes out from the C-shaped aperture. Credit: Rabee Ikkawi, University of California, Riverside |
A laser that focuses light into a 30-nanometer-wide spot could be an important advance toward ultra-high-density hard disks. Researchers at the University of California, Riverside (UCR), and at the University of Houston, in Texas, who have developed the nanolaser, say that it could lead to hard disks with 10 terabits of data packed into a square inch.
Today, hard disks can carry up to 200 gigabits per square inch. Data is stored magnetically. Using existing technology, manufacturers could increase a disk's capacity to at most one terabit per square inch. The nanolaser is an important step toward a disk-writing system that many researchers are currently working on. Such a system would use both light and magnetic fields to store data on a disk, packing up to 50 terabits per square inch of data.
The smaller the light spot of the laser, the smaller the bit size, which means more bits per square inch. Right now, the laser can concentrate 250 nanowatts of power on a 30-nanometer-wide spot. "Our technology can be scaled down to 5 to 10 nanometers for sure," says Sakhrat Khizroev, an electrical-engineering professor who is leading the work at UCR. A 10-nanometer spot size should be small enough to get a density of 10 terabits per square inch.
Present-day magnetic storage technology has doubled data density on hard disks nearly every year for the past three decades. But now the technology is approaching its limit. On a hard disk, each bit is a tiny area in which the material's crystals all have their magnetic fields aligned in the same direction. As more data is recorded on a disk, bits get smaller and comprise fewer crystals of the material. At about one terabit per square inch, the bit areas become so tiny that the crystals do not have enough energy to keep their magnetic fields aligned, and the bits end up losing their information.
Hard-disk manufacturers such as Seagate are now looking at a new method to store more data on disks. The technique, called heat-assisted magnetic recording, involves using a tightly focused light spot to heat up the bits when they are being recorded. This gives the magnetic crystals energy to retain their magnetic-field orientations. "There are various ways one could imagine bringing light on the disk," says Mark Kryder, an electrical- and computer-engineering professor at Carnegie Mellon University. "The most elegant way would be to use a nanolaser."
So far, the challenge has been to make a laser that delivers sufficient energy into a small enough light spot. With previous lasers, Khizroev says, "the light, when focused on a 30-nanometer spot size, has energies that are a fraction of a nanowatt." He and his colleagues make their 250-nanowatt laser by depositing a very thin layer of aluminum on the emitting side of a semiconductor diode laser. Then they focus a beam of positive gallium ions on the aluminum to etch tiny nanoscale apertures. As predicted by physics theory, a C-shaped aperture lets the most energy come through into the smallest spot size. Khizroev says that his colleagues are now trying to engineer the laser with an even smaller spot size of 5 to 10 nanometers.
Ed Schlesinger, head of the Electrical and Computer Engineering department at Carnegie Mellon, says that the new nanolaser is "an important aspect of making heat-assisted magnetic recording a reality." But he cautions that there are many engineering challenges to solve before the technology can be brought to market. They include mounting the laser on a slider so that it can move to various areas of the hard disk to record data, designing a new disk material that works with heat-assisted recording, and making disk lubricants that can handle the high temperatures during the heat-assisted writing process.
"Heat-assisted magnetic recording is a real systems problem and requires development and progress on a lot of fronts simultaneously," Schlesinger says. "The nanolaser is a nice step forward and brings the technology closer."
 IMAGE: Anna Demian/Randi Silberman |
| Pushing Pencils: Graphene, found in pencil marks, is a candidate material for making future transistors. It's extracted from graphite crystals [right] using sticky tape. |
The little smudges you leave behind whenever you use a pencil could be the key ingredient of the next revolution in computer circuitry, according to experts around the globe. Part of what shears off from the graphite in a pencil is a substance known as graphene, a one-atom-thick crystal with remarkable electrical properties that may overcome the physical limits silicon faces as transistors shrink to ever-smaller sizes.
Silicon's remarkable run as ruler of the chip world may be nearing an end as engineers eventually lose the ability to make faster silicon transistors by making them smaller. In the hunt for what comes next, carbon nanotubes have gotten a big chunk of the attention, but if the current explosion of research activity is any indication, it may be graphene that wins in the end. This spring saw a flurry of breakthroughs surrounding graphene, culminating in the creation of what may be the smallest transistor ever made—one atom thick by 10 to 50 atoms wide.
Like carbon nanotubes, graphene is a crystal structure of carbon atoms but arranged in a flat plane instead of a cylinder. The electrons in graphene behave as if they have no mass. Like photons—but unlike electrons in other materials—the electrons move at a constant speed, regardless of how much energy each one has.
A transistor built out of graphene, therefore, should operate much faster than a comparable one made from silicon. Michael S. Fuhrer, a physicist at the University of Maryland's Center for Nanophysics and Advanced Materials, recently showed that at room temperature electrons in graphene move at 200000 centimeters per second for every volt per centimeter of electric field, 100 times faster than in silicon. “All other things being equal, that would translate into a 100 times faster transistor,” he says.
Graphene has been known for decades as a single plane of graphite, but it was only in 2004 that Andre Geim and Kostya Novoselov of the University of Manchester, England, were able to isolate it by the simple act of pressing a piece of tape to a graphite crystal and placing it on a silicon substrate. In April, the two researchers described their transistor, 10 to 50 atoms wide and built by etching a pattern into graphene. [read more]
Since a computer microprocessor is veined with electric circuitry, it might seem like a bad place to put water. But IBM Corp. researchers believe that sloshing water through hair-thin pipes inside chips will solve a vexing problem facing next-generation computers.
That problem is heat.
As chips get smaller and smaller, cramming more processing power into ever-tinier spaces, the heat thrown off by the miniature circuits becomes harder to manage. Cooling measures used now to avoid chip meltdowns, including "heat sinks" made from heat-absorbing materials, might not work on tinier scales.
In fact, in a future microprocessor design IBM is exploring -- in which chips are stacked vertically to save space and enhance performance, rather than arrayed next to each other -- the heat-to-volume ratio exceeds that of a nuclear reactor.
To address that, IBM researchers say they could pipe water in between chips that are sandwiched together. The system, which IBM planned to explain Thursday at a technical conference, uses pipes that are just 50 microns wide -- 50 millionths of a meter. The tiny tubes are sealed to prevent leaks and electrical shorts.
Even these micro amounts of water can handle prodigious cooling chores, because water is much more efficient than air at absorbing heat. That is why some high-end computers long have used water cooling. The new trick here is that IBM expects to do it at the miniature scale, inside chips.
"It's never been applied this close to the heart of the matter," said analyst Richard Doherty of the Envisioneering Group.
Yogendra Joshi, an engineering professor at the Georgia Institute of Technology, said aspects of IBM's approach already have been shown by other researchers. But he said the company deserves credit for trying to push the idea toward commercialization.
"There has been a great aversion to piping liquids through electronics," Joshi said. "That's understandable."
However, IBM's tiny pipes aren't out of the lab yet. They're at least five years from becoming available.
[Source: Technology Review, Published by MIT]Last September, Israeli jets bombed a suspected nuclear installation in northeastern Syria. Among the many mysteries still surrounding that strike was the failure of a Syrian radar—supposedly state-of-the-art—to warn the Syrian military of the incoming assault. It wasn't long before military and technology bloggers concluded that this was an incident of electronic warfare—and not just any kind.
Post after post speculated that the commercial off-the-shelf microprocessors in the Syrian radar might have been purposely fabricated with a hidden “backdoor” inside. By sending a preprogrammed code to those chips, an unknown antagonist had disrupted the chips' function and temporarily blocked the radar.
That same basic scenario is cropping up more frequently lately, and not just in the Middle East, where conspiracy theories abound. According to a U.S. defense contractor who spoke on condition of anonymity, a “European chip maker” recently built into its microprocessors a kill switch that could be accessed remotely. French defense contractors have used the chips in military equipment, the contractor told IEEE Spectrum. If in the future the equipment fell into hostile hands, “the French wanted a way to disable that circuit,” he said. Spectrum could not confirm this account independently, but spirited discussion about it among researchers and another defense contractor last summer at a military research conference reveals a lot about the fever dreams plaguing the U.S. Department of Defense (DOD).
Feeding those dreams is the Pentagon's realization that it no longer controls who manufactures the components that go into its increasingly complex systems. A single plane like the DOD's next generation F-35 Joint Strike Fighter, can contain an “insane number” of chips, says one semiconductor expert familiar with that aircraft's design. Estimates from other sources put the total at several hundred to more than a thousand. And tracing a part back to its source is not always straightforward. The dwindling of domestic chip and electronics manufacturing in the United States, combined with the phenomenal growth of suppliers in countries like China, has only deepened the U.S. military's concern.
Recognizing this enormous vulnerability, the DOD recently launched its most ambitious program yet to verify the integrity of the electronics that will underpin future additions to its arsenal. In December, the Defense Advanced Research Projects Agency (DARPA), the Pentagon's R&D wing, released details about a three-year initiative it calls the Trust in Integrated Circuits program. The findings from the program could give the military—and defense contractors who make sensitive microelectronics like the weapons systems for the F‑35—a guaranteed method of determining whether their chips have been compromised. In January, the Trust program started its prequalifying rounds by sending to three contractors four identical versions of a chip that contained unspecified malicious circuitry. The teams have until the end of this month to ferret out as many of the devious insertions as they can.
Vetting a chip with a hidden agenda can't be all that tough, right? Wrong. Although commercial chip makers routinely and exhaustively test chips with hundreds of millions of logic gates, they can't afford to inspect everything. So instead they focus on how well the chip performs specific functions. For a microprocessor destined for use in a cellphone, for instance, the chip maker will check to see whether all the phone's various functions work. Any extraneous circuitry that doesn't interfere with the chip's normal functions won't show up in these tests.
“You don't check for the infinite possible things that are not specified,” says electrical engineering professor Ruby Lee, a cryptography expert at Princeton. “You could check the obvious possibilities, but can you test for every unspecified function?”
[read more]The next afternoon (Session 34, "CMOS Devices -- Advanced Device Structures"), the far limits of CMOS FET technology were shown by Samsung as experimental results of uniaxially strained {110} silicon nanowire transistor (SNWT) channels using an embedded SiGe Source/Drain for greatly improved pMOS performance. Starting with either SOI or bulk silicon wafers, they first grow embedded SiGe (20-40nm thick) and then Si. After hardmask patterning and a clever sequence of etching, the bottom of the grown Si {110} has become SNW floating above the removed SiGe, but the SiGe beneath the S/D remain, and the inherent SiGe/Si lattice-mismatch compressively stresses SNW to provide 1534μA/μm for pMOS. They saw nFET performance only ~15% lower regardless of {110} or {100} orientation, so good overall CMOS results are obtainable using {110}.
Beyond FETs and cross-bar architectures lies a technology concept still mostly disbelieved by the mainstream: quantum electronics. The IEDM plenary session included a talk by Hiroyuki Sakaki, from the Toyota Technological Institute at the U. of Tokyo, on “Roles of Quantum Nanostructures on the Evolution and Future Advances of Electronic and Photonic Devices.” By controlling the electrons within nanoscale layered structures, quantum confinement results in effective two-dimensional electrons and the ability to form devices such as resonant tunneling diodes, quantum wire FETs, quantum dot lasers, and planar superlattice FETs.
However, commercial quantum electronics still remains out in the future. Use of carbon nanotubes (CNT) grown from catalyst particles shows promise, “but it has been very difficult to control the site selection, as well as other parameters,” according to Sakaki. Charge storage phenomena in quantum dots using either Si or InAs appear like the most likely near-term applications. Though if this is merely an extension of flash memory cell technology, does it really count as “quantum electronics?”
In 20 years, will we see a non-FET-based computer? The aggregate opinion seemed to be “yes,” but don’t expect people in the industry who have lived with it forever to be able to think “outside the FET” and develop something revolutionary.
