Wednesday, May 11, 2011
இதய திசுக்கள் பாதிப்படைந்தால் தானாகவே சரிசெய்து கொள்ளும் முறை: விஞ்ஞானிகள் சாதனை
 பாதிக்கப்பட்ட இதயத்தில் திசுக்களை சரிசெய்து மீண்டும் துடிப்புடன் செயல்பட வைப்பதற்கான புதிய செல் தெரபி முறையை ஆய்வாளர்கள் கண்டறிந்துள்ளனர்.இந்த முறையின் மூலம் திசுக்கள் தாங்களாகவே சரி செய்து கொண்டு செயல்படுகின்றன. இந்த ஆய்வு குறித்த கட்டுரை நேஷனல் அகாடமி ஆப் சயின்சில் வெளியிடப்பட்டுள்ளது. கொலம்பியா பல்கலைகழகத்தின் ப்யூ பவுண்டேஷன்ஸ் ஸ்கூல் ஆப் என்ஜினியரிங்கின் உயிரி மருத்துவ துறை பேராசிரியர் கார்டெனா வுன்ஜிக் நோவகோவிக் தலைமையில் நடந்த ஆய்வில் இந்த புதிய செல் தெரபி முறை கண்டறியப்பட்டுள்ளது. மாரடைப்பு காரணமாக இதயம் மயோ கார்டியஸ் இன்பார்க்கஷன் என்ற பாதிப்பு நிலைக்கு ஆளாகிறது. இந்த பாதிப்பை சரி செய்ய சேதம் அடைந்த திசுக்கள் பகுதியில் ரத்த ஓட்டம் உச்ச நிலையில் இருக்கும் வகையில் மனித சீரமைப்பு செல்களை ஆய்வாளர்கள் பயன்படுத்தினர். புதிய மருத்துவ தொழில்நுட்பம் நல்ல பலனை அளித்துள்ளது என டொக்டர் வுன்ஜக் நோவகோவிக் தெரிவித்தார். இந்த புதிய முறையின் மூலம் பாதிப்படைந்த செல்களை தாங்களாகவே சேதத்தை சரிசெய்து கொண்டு மீண்டும் சிறப்பாக செயல்படுகின்றன. இதனால் இதய ரத்த ஓட்டமும் தடையின்றி நடைபெறும். இதய நோய்களும் தவிர்க்கப்படுகின்றன. இதய தசை கட்டமைப்பு மற்றும் இதர இதய சீரமைப்பு ஆராய்ச்சிகளுக்கு மனித ஆதாரச் செல்லின் இதர வகைகளை பயன்படுத்தப் போவதாகவும் ஆய்வாளர்கள் நம்பிக்கை தெரிவித்தனர். ஆதாரச் செல்கள் மூலம் பாதிக்கப்பட்ட இதய ரத்த குழாய்கள் நன்கு வளர்கின்றன. புரதமும் உரிய அளவில் உற்பத்தி ஆகிறது. இதன் மூலம் இதய தசை பகுதியில் சேதமடைந்த பூர்விக திசு தன்னை சரிசெய்து கொண்டு இயல்பு நிலைக்கு திரும்புகிறது. |
Developing Cancer Drugs Based on Genomics
A new startup, funded with $40 million from Third Rock Ventures, will develop drugs aimed at molecularly defined cancers.
Blueprint Medicines, a startup based in Cambridge, Massachusetts, plans to use the growing amount of genomic information about cancer to create new drugs targeted at the mechanisms that drive specific subtypes of the disease. The company, which announced its creation last week with $40 million in funding from Third Rock Ventures, reflects a growing trend toward defining cancers not by their location in the body but by the particular collections of genetic mistakes that enable tumor cells to grow out of control.
"How the community, both academic and industry, understands cancer is really shifting from largely a pathology-centric viewpoint—classifying cancers based on what we can see in the microscope—to a molecular viewpoint," says Chris Varma, the company's president and cofounder. "What we find is that the mechanisms that are driving cancer come up again and again in different environments. The same mechanism responsible for some breast cancers could be driving a subset of brain cancer or melanoma."
The growing understanding of cancer genetics has enabled researchers to develop an increasing number of drugs designed to zero in on cancer cells. Varma says Blueprint will use genomics and novel chemistry to develop such drugs in a more systematic way, targeting a broader range of molecular mistakes.
In addition to Varma, cofounders include Nicholas Lydon and Brian Druker, who led the development of Gleevec, one of the first targeted cancer drugs; Scott Lowe, deputy director of the Cold Spring Harbor Laboratory Cancer Center; and David Armistead, a biotech entrepreneur.
Genomic data on cancer has been pouring in to public databases over the last few years, thanks to projects such as the Cancer Genome Atlas, an NIH-funded effort to read the entire DNA sequence of various cancers. "There are now literally hundreds of genome efforts on various types of cancer," says Lowe, "and all of this data is in the public domain and can be readily accessed."
One of Blueprint's goals will be to use this information to identify new drug targets. "Right now, we have lot of experience in identifying these alterations; we can catalogue and sequence genomes and identify changes present in particular cancers," says Michael Hemann, a cancer researcher at MIT who isn't involved with Blueprint. "The problem is, what do we do with that information? Which of these changes are relevant, and what do we do about it? For example, cancer cells can accumulate many mutations, some that drive abnormal growth and some that have no effect. And scientists need to identify which is which."
Blueprint is building a platform that will initially use computational algorithms to analyze genomic data for potential molecular mistakes linked to cancer. For example, they would detect whether multiple data sets drawn from cancers of different types reflect mutations in the same enzymes. Researchers would then run tests on cells or animals to determine which of the mutations identified actually drive the growth of cancer cells and are thus the most promising targets for cancer drugs.
The company is also building a proprietary library of chemical compounds called kinase inhibitors—molecules that block activity of kinase enzymes, which have been linked with cancer. Armistead says the researchers will use computational modeling and x-ray crystallography to create a library of structures and then test the compounds' ability to inhibit different kinases. They plan to generate and screen the library within the next 12 to 18 months. "We also have a short list of targets we already have interest in, which we will begin working on immediately," says Armistead.
Will Electric Vehicles Finally Succeed?
A new wave of plug-in hybrids and all-electric vehicles will have to overcome a familiar nemesis: battery costs.
At the end of 2010, GM and Nissan each began selling cars that run on electricity most or all the time. The Volt and the Leaf are only the first of dozens of new electric vehicles and plug-in hybrids to come: every major automaker has promised to start selling such cars over the next few years. Toyota, which has led the world in its development of gas-electric hybrid technology, plans next year to introduce a new version of its Prius that will be able to run on electricity alone for short distances. Meanwhile, startups such as Coda Automotive are trying to break into the auto industry with plug-in hybrids and all-electric cars—following the lead of Tesla Motors, whose electric sports car may have helped set the new wave in motion when it was introduced in 2006.
If these cars become popular with buyers, it will mark the beginning of the biggest shift the auto industry has seen for decades: a shift away from an almost exclusive reliance on petroleum and the internal-combustion engine. GM, just emerging from bankruptcy, is counting on the Volt to change its image from purveyor of the Hummer and other large SUVs to leader in innovation and energy efficiency. For its part, Nissan is staking much of its future on electric vehicles; over the next few years it plans to ramp up production to sell hundreds of thousands of them annually, far more than any other automaker.
Ultracapacitors to Boost the Range of Electric Cars
Ultracapacitors to Boost the Range of Electric Cars
New energy-storage technology could surpass today's batteries in capacity and durability.
A startup called Nanotune says its ultracapacitor technology could make electric cars cheaper and extend their range. The company, based in Mountain View, California, has developed a way to make electrodes that results in ultracapacitors with five to seven times as much storage capacity as conventional ones.
Conventional ultracapacitors, which have the advantage of delivering fast bursts of power and can be recharged hundreds of thousands of times without losing much capacity, are too expensive and store too little energy to replace batteries.
Nanotune, however, which has raised $3 million from the venture capital firm Draper Fisher Jurvetson, says its ultracapacitors are close to competing with batteries in terms of energy storage, and could soon surpass them. Using a conventional electrolyte, the company has demonstrated energy storage of 20 watt-hours per kilogram, as opposed to roughly five watt-hours for a conventional ultracapacitor. Using a more expensive ionic-liquid electrolyte, it has made ultracapacitors that store 35 watt-hours per kilogram. By the end of the year, the company hopes to approximately double this storage capacity, says Nanotune CEO Kuan-Tsae Huang. At 40 watt-hours per kilogram, the ultracapacitors would be an improvement over the batteries used in some hybrid vehicles.
In recent months, several startups have announced that they're using nanotechnology to make better ultracapacitors. Each hopes to help solve one of the biggest problems with electric cars today: their batteries' high cost and limited storage capacity. Nissan, for example, to make its electric Leaf affordable, had to limit the size of the battery pack, resulting in a range of just 73 miles.
Part of the reason battery systems are so expensive and bulky is that the batteries degrade as they're used, especially when exposed to extreme temperatures—so automakers often augment them with cooling and heating systems, and add extra battery cells to offset losses in performance over time. Ultracapacitors could sidestep this problem, because they can be recharged without degrading and can work well in a wide range of temperatures.
Eventually, Huang says, it may be possible to make ultracapacitors that store 500 watt-hours per kilogram—about three to four times more than the lithium-ion batteries used in cars today. The practical benefit could be even greater. Cars are often engineered to use only half the storage capacity of their batteries, to keep them from degrading. But almost all of an ultracapacitor's storage capacity can be used.
Nanotune's technology is very expensive now—between $2,400 and $6,000 per kilowatt-hour. (The Department of Energy has proposed a goal of $250 per kilowatt-hour to make electric vehicles competitive with conventional ones.) Nanotune says, however, that its costs could come down to less than $150 per kilowatt-hour if the prices of some key materials, such as electrolytes, continue to fall, and as manufacturing is scaled up.
The company's energy-storage projections are based on several advances it is working on. Nanotune is currently making electrodes with pores that are about 4 to 5 nanometers across, but it says it can make them smaller (high porosity leads to high surface area, which makes it possible to store a large amount of charge) and tune them to match the needs of different electrolytes—the ion-conducting materials the electrodes are immersed in.
The company is also looking into using ionic liquids rather than conventional organic electrolytes. These increase the voltage of the system, greatly increasing energy storage, but typically they aren't compatible with conventional ultracapacitor electrodes. Finally, the company hopes to make use of recent academic findings that suggests that adding small amounts of ruthenium to the ultracapacitors can increase energy storage.
Nanotune isn't the first company to claim it can make ultracapacitors with very high energy storage. Others have found this promise hard to deliver. Increasing surface area can improve storage capacity only so much, since at some point the storage is limited by the ions in the electrolyte. Ionic liquids help with this, but they have significant shortcomings, says Joel Schindall, a professor of electrical engineering and computer science at MIT. (A company called FastCap Systems, which is developing ultracapacitors using carbon nanotubes, was spun out of his lab.) They're very expensive, for one thing, and some operate well only in a limited temperature range, making them impractical for cars.
Schindall says, however, that Nanotune can fall short of its very high energy goals and still improve the competitiveness of electric vehicles and hybrids. Given the durability of ultracapacitors, even achieving energy storage of 100 watt-hours per kilogram—close to that of lithium-ion batteries—"would be fantastic."
The company's mobile operating system can now control everything from lighting to gym equipment.
Google's Android operating system may have been created for phones and refined for tablets, but the OS is set to move beyond the bounds of mobile devices.
Today, Google announced a new class of Android devices for the home during the opening keynote at its annual I/O developer's conference in San Francisco. These devices—dubbed "Tungstens"—act as an intermediary between an Android phone or tablet and a suitably enabled home appliance. They would allow users to remotely control everything from lighting to refrigerators.
The company demonstrated how a Tungsten could make playing a game on an Android tablet more immersive: explosions and gunfire set the special lights in the room flickering with every blast. New software that makes it easier for Android devices and their apps to interface with other devices and objects, including home automation equipment, was also demonstrated.
"We'd like to think of Android as the operating system for your home," said Joe Britt, who is leading the Android@Home project. "We're extending the Android OS to include new services that allow Android devices to discover, connect, and communicate with devices in the home."
Britt showed off two conceptual Tungsten devices to illustrate Google's vision for Android and its apps taking control of the home. One took the form of a six-inch-square box with lights along its edges, and the other was a white sphere roughly the same size. "A Tungsten device runs the Android OS and the Android@Home framework," said Britt. "It's always on, and always connected to the cloud."
Britt called these two Tungsten devices "reference hardware," a term used to describe prototypes intended to inspire other companies to design their own more refined devices. Because Android is open-source software, Google will make available all the hardware specifications needed for others to build their own Tungsten devices.
Tungsten devices use Wi-Fi to connect to the Internet and other devices, as well as a new, low-power wireless standard of Google's own invention to link with other devices. The gaming demo involved Tungsten-controlled LED lightbulbs made by the company LightingScience, which had the Google wireless standard built in. Britt also hinted that accessories would be released to enable existing devices to come under the control of Android@Home.
During the demo, a Tungsten device with a built-in RFID reader was used to interact with CD cases with RFID tags. When a CD case was touched to the Tungsten prototype, a chime sounded. "That means the entire CD has been added to my library," said Britt. A second tap of the CD caused the device to play the album, streaming the music from Google's new cloud music locker.Britt appealed to developers to create apps that take control of devices in the home. "You could make an alarm app that slowly ramps up the light in the room and plays your favorite music," he said. "Imagine using Android@Home to control an irrigation system to create a real-world Farmville app. If you lose the game, your garden dies."
Britt's colleague Matt Hershenson, director of hardware for Android, introduced a new feature coming soon to the most recent release of Android, Honeycomb, due out later this year. The new feature is a software protocol that lets the operating system connect with many different devices.
"What if your Android devices could integrate more fully with your workout?" he asked as a colleague stripped down to cycling shorts, mounted an exercise bike, and plugged his Android phone into it.
The new software protocol allowed the bike to open an app that used the pedaling of the bike to control a simple game. "If the phone didn't already have a compatible app, the bike would send the phone to the market to download it," said Hershenson.
A second, larger-scale demo saw a tablet used to control a 5,000-pound wooden tilt table large enough to park a car on. The tilt of an Android tablet was fed to motors so that the table mirrored the tablet's movement, allowing a user to steer a bowling ball around a maze.
The forthcoming Honeycomb refresh will also support all existing USB devices out of the box. One consequence, as demonstrated at the conference, is that game controllers can be used with Android devices, bringing tablets and connected TV devices running Android into competition with consoles and gaming PCs.
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