A new type of device that uses both heat and light from the sun should be more efficient than conventional solar cells, which convert only the light into electricity.

The device relies on a physical principle discovered and demonstrated by researchers at Stanford University. In their prototype, the energy in sunlight excites electrons in an electrode, and heat from the sun coaxes the excited electrons to jump across a vacuum into another electrode, generating an electrical current. The device could be designed to send waste heat to a steam engine and convert 50 percent of the energy in sunlight into electricity–a huge improvement over conventional solar cells.

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The most common silicon solar cells convert about 15 percent of the energy in sunlight into electricity. More than half of the incoming solar energy is lost as heat. That’s because the active materials in solar cells can interact with only a particular band of the solar spectrum; photons below a certain energy level simply heat up the cell.

One way to overcome this is to stack active materials on top of one another in a multijunction cell that can use a broader spectrum of light, turning more of it into electrical current instead of heat, for efficiencies up to about 40 percent. But such cells are complex and expensive to make.

Looking for a better way to take advantage of the sun’s heat, Stanford’s Nicholas Melosh was inspired by highly efficient cogeneration systems that use the expansion of burning gas to drive a turbine and the heat from the combustion to power a steam engine. But thermal energy converters don’t pair well with conventional solar devices. The hotter it is, the more efficient thermal energy conversion becomes. Solar cells, by contrast, get less efficient as they heat up. At about 100 °C, a silicon cell won’t work well; above 200 °C, it won’t work at all.

The breakthrough came when the Stanford researchers realized that the light in solar radiation could enhance energy conversion in a different type of device, called a thermionic energy converter, that’s conventionally driven solely by heat. Thermionic converters consist of two electrodes separated by a small space. When the positive electrode, or cathode, is heated, electrons in the cathode get excited and jump across to the negative electrode, or anode, driving a current through an external circuit. These devices have been used to power Russian satellites but haven’t found any applications on the ground because they must get very hot, about 1,500 °C, to operate efficiently. The cathode in these devices is typically made of metals such as cesium.

Melosh’s group replaced the cesium cathode with a wafer of semiconducting material that can make use of not only heat but also light. When light strikes the cathode, it transmits its energy to electrons in the material in a way that’s similar to what happens in a solar cell. This type of energy transfer doesn’t happen in the metals used to make these cathodes in the past, but it’s typical of semiconductor materials. It doesn’t take quite as much heat for these “preëxcited” electrons to jump to the anode, so this new device can operate at lower temperatures than conventional thermionic converters, but at higher temperatures than a solar cell.

The Stanford researchers call this new mechanism PETE, for photon-enhanced thermionic emission. “The light helps lift the energy level of the electrons so that they will flow,” says Gang Chen, professor of power engineering at MIT. “It’s a long way to a practical device, but this work shows that it’s possible,” he says.

The Stanford group’s prototype, described this month in the journal Nature Materials, uses gallium nitride as the semiconductor. It converts just about 25 percent of the energy in light into electricity at 200 °C, and the efficiency rises with the temperature. Stuart Licht, professor of chemistry at George Washington University, says the process would have an “advantage over solar cells” because it makes use of heat in addition to light. But he cautions: “Additional work will be needed to translate this into a practical, more efficient device.”

The Stanford group is now working to do just that. The researchers are testing devices made from materials that are better suited to solar energy conversion, including silicon and gallium arsenide. They’re also developing ways of treating these materials so that the device will work more efficiently in a temperature range of 400 °C to 600 °C; solar concentrators would be used to generate such high temperatures from sunlight.

Even at high temperatures, the photon-enhanced thermionic converter will generate more heat than it can use; Melosh says this heat could be coupled to a steam engine for a solar-energy-to-electricity conversion efficiency exceeding 50 percent. These systems are likely to be too complex and expensive for small-scale rooftop installations. But they could be economical for large solar-farm installations, says Melosh, a professor of materials science and engineering. He hopes to have a device ready for commercial development in three years.

By Katherine Bourzac. Source.

Even a farmer can use a mobile to remote control pumps, thanks to Nano Ganesh, a mobile phone based application developed by Ossian Agro Automation.”The farmer can monitor and check availability of the power at the pump, can switch the pump on/off, and acknowledge the on/off status of water pump from any place. All he has to do is pick his mobile phone, punch a few keys and the control is in his hands,” says Santosh Ostwal, CEO, Ossian Agro Automation.

How does Nano Ganesh work?

On the deployment of Nano Ganesh, a pre-set code is given to the farmer to switch on/off the pumpset. To switch it on, a farmer has to call up the mobile attached in the starter panel of the pump. The mobile attached in the starter panel will confirm the availability of power/electricity supply in the pumpset location by a long beep following which the farmer can dial the preset code to switch on the pump. After dial the code, the farmer (user) has to confirm the function by a feedback tone and then cut the call. For switching off the pumpset, the same process has to be repeated, ofcourse with a different preset code to switch off the pump.

Wow Factor

At first sight, Nano Ganesh seems simple technology but making this simple technology workable in rural atmosphere facing problems like voltage fluctuations, shock hazards, open wiring, marshy terrain etc didn’t come easy.

An affordable option

Realising the monetary limitations of the farmer, Nano Ganesh only demands a low cost wireless connectivity with voice transmission and DTMF transmission. Even basic handsets are powered with such technology making this new remote control an affordable option for farmers. “We tap the DTMF information by a headset jack pin and convert them into the desired digital signals with the help of DTMF decoders and multiplexing units to control the pump-set. Also, we had to feed in low frequency oscillations corresponding to the load on/off status to the MIC inputs of the mobile headset,” says Ostwal.

Nano Ganesh also has a long life span making it a worthwhile investment for the penny-wise farmer. “It is life tested in the hazardous areas by specially developed simulation standards/ techniques by Ossian Agro Automation. The predicted life span of the gadget is 5 years,” says Ostwal.

Combat harsh rural environment

Further, Nano Ganesh has been able to overcome harsh rural conditions in India. It can perform in wide range of supply voltages. “Nano Ganesh performs perfectly in the voltage tolerances of plus or minus 50 percent i.e. it is protected to sustain the voltage level of 3 phase 500 volts and it can perform perfectly even if the voltage level goes down to 3 phase 250 volts,” explains Ostwal.

It is also free from electrical bounces in the fluctuating electricity conditions. The special relay logics and optical isolations at proper stages makes Nano Ganesh free of back bounce effects. “Special relay logics or bounce back free technology is a must when the load is heavy and inductive as all on/off commands or status are lost as soon as the switching of the load happens. To avoid this, we decided to drive the relays through optical isolators, which isolate the ground paths of the micro-controllers and driving relays, ensuring that the bouncing electro motive force (EMF) doesn’t reach the UC circuitry. This can be also achieved by interlocking driver relays with hold on techniques used in electrical contactors and starters system. But, this makes the system bulky and power hungry. Relay logics are more sturdy and robust,” says Ostwal.

Anti-theft mechanism

Further, it has an anti-theft system. “We use mobiles with auto dialing facility to run the anti-theft system. The auto dialer of the mobile is triggered automatically by a relay and sensor mechanism. On sensing a theft threat, an alert call is given to a pre-stored number automatically,” says Ostwal.

A guiding light in the future

In the future, Nano Ganesh technology could be used in controlling any electrical appliances. “Street lights and neon signs boards, fountains and water falls, air conditioners, industrial heaters, security systems etc — Nano Ganesh technology can be the remote to control them all,” says Ostwal. Mobiles are all set to be the new aged robots helping us control all our electrical gadgets!

Contact: Nano Ganesh

• Charles Brush built what is considered the first automatic wind turbine for generating electricity. The turbine, built in 1888 in Ohio, had a 50-foot diameter and 144 blades. The industry has since trimmed turbines down to three blades. It has also gone overseas. While the U.S. has more installed wind capacity than anyone else, the only top U.S. wind manufacturer remains General Electric: they got into the business by buying the wind division of disgraced, defunct Enron. One of the most promising U.S. startups is Nordic Windpower, located in Berkeley by way of Sweden.

• Calvin Fuller, Daryl Chapin and Gerald Pearson created the first silicon photovoltaic cell at Bell Labs in 1954. It was only four-percent efficient, but Bell raised the figure to 11 percent soon after. First Solar and SunPower hail from the U.S. — and we mint a lot of startups — but the U.S. is a far smaller market than Europe, and Suntech and Yingli have begun to demonstrate that we don’t have a monopoly on quality.

• A chemistry professor at the State University of New York Binghamton, M. Stanley Whittingham led a research team at Exxon that resulted in the first lithium ion battery. Whittingham’s titanium sulfide battery, however, was not a hit — Sony’s lithium cobalt battery became the standard in the early 1990s. The battery industry is now based in Asia.

• In 1991, the Department of Energy kicked off the $90 million U.S. Advanced Battery Consortium to develop nickel metal hybrid batteries for hybrid cars, a car design championed a century earlier by Ferdinand Porsche. The effort scared Japan so much that Honda and Toyota began to develop hybrids. Before tangible results came in, the DOE shifted funding to hydrogen.

• In 1976, General Electric Ed Hammer invented something that many thought impossible: the compact fluorescent bulb. Although GE liked the idea, CFLs would require entirely new manufacturing facilities, which would cost $25 million. “So they decided to shelve it,” Hammer told me in 2007. CFLs only came to market because the design leaked out — others copied it before GE had a licensing program. “That’s how it became widespread,” he said.

So why do we suck so much at green commercialization, while excelling at transforming science projects like search engines, microprocessors and microbes into Google, Intel and Genentech? The reasons are:

]]> http://www.sunilreddy.com/?feed=rss2&p=1696 0 http://www.sunilreddy.com/?p=1692 http://www.sunilreddy.com/?p=1692#comments Sat, 10 Jul 2010 09:58:27 +0000 Sunil http://www.sunilreddy.com/?p=1692 The company is developing crops that tolerate salty soils.

Around the world, a billion acres of agricultural land lay abandoned. In the United States, 15 million acres of cropland falls under this category. Decades of repeated irrigation and declining water quality have made much of this once-productive land too salty to support plant growth. Among the strategies to put this land back to use is to develop crops that can tolerate high-salinity soils.

Last week, Ceres, a biotechnology company in Thousand Oaks, CA, announced that it had developed a trait that allows several common crops to grow under highly saline conditions, even in seawater. Ceres researchers have tested the trait in Arabidopsis thaliana, rice, and switchgrass, a hardy perennial that’s used as a feedstock for making ethanol and other biofuels. “The fact that we’ve seen this very high-level salt tolerance in three different plant species gives us a high degree of confidence that this trait will recapitulate itself in other energy grasses as well,” says Ceres CEO Richard Hamilton.

The ability to grow energy crops, such as switchgrass, on marginal lands means that they wouldn’t have to compete for the best farmland. “The great opportunity is that we could use land unsuitable for food crops,” says Chris Field, director of the department of global ecology at the Carnegie Institution of Washington in Stanford, CA. But he cautions that there still could be competition for water, depending on where the crops are grown. “It depends on whether your land or the water is the limiting resource,” he says.

Indeed, irrigation is to blame for turning much of the world’s cropland fallow. When a field is irrigated, water evaporates, and salts get left behind in the soil. Over decades, the salts build up and degrade the soil’s quality. “There’s not only salinity now, but it’s getting worse,” says Mark Tester, a plant physiologist at the Australian Centre for Plant Functional Genomics at the University of Adelaide and director of the Australian Plant Phenomics Facility. “It’s inevitable, and this is compounded by the fact that the world’s water supplies are under increasing pressure. The salinity of these systems is being accelerated by the decreasing quality of water.”

Ceres is not revealing the gene used to convey the saline tolerance or its mechanism because it is filing for intellectual property protections on the discovery. But plants that grow in salty conditions generally do so through one of three different mechanisms: they form a barrier to prevent salt from entering the shoot, they actively pump out the salt that gets in, or they store the salt in vacuoles to isolate it from harming the plant cells.

Ceres’s next step is to test the plants in the field. “We have not observed at this point any increase in water requirements for the crop,” Hamilton says. “But before deploying it on a large scale, we have more testing that we want to do.”

By Corinna Wu

Source.

A decade ago, Germany launched a renewable-­energy plan on an unprecedented scale. Its parliament, the Bundestag, enacted a law obligating the nation’s electric utilities to purchase green power at sky-high rates–as much as 60 cents per kilowatt-hour for solar–under fixed contracts lasting up to 20 years. (German market prices for electricity, largely produced by coal and nuclear plants, were about 12 cents per kilowatt-hour.) The idea behind this “feed-in tariff” was that anyone would be able to build a renewable-power plant–or install rooftop solar panels–and be guaranteed predictable profits by feeding energy into the grid, where utilities would buy it at premium prices. The higher costs would be passed on as monthly surcharges to ratepayers, spread out among all homes and businesses in a country of about 80 million people. Fossil and nuclear fuels amount to “global pyromania,” said Hermann Scheer, the German politician who championed the policy. “Renewable energy is the fire extinguisher.”

Now, as the United States and other nations look toward creating their own policies for dealing with climate change, the effectiveness of the German experiment is a subject of debate. From one perspective, the Renewable Energy Sources Act of 2000 has exceeded its aims. Germany’s first target was to get at least 10 percent of its electric power from renewable sources by 2010. The German grid now gets more than 16 percent of its electricity from these sources, and the government has raised its target for 2020 from 20 percent to 30 percent. The country avoided pumping about 74 million metric tons of carbon dioxide into the atmosphere in 2009. The German environment ministry also touts a side benefit: nearly 300,000 new jobs in clean power. As a result, the feed-in tariff has the support not only of the left-leaning politicians who originally backed it but also of most of the skeptics in the right-leaning parties that fought against it, says Claudia Kemfert, who heads the energy department at the German Institute for Economic Research in Berlin. “The skepticism is over,” she says. “We’re celebrating the success.”

But from another perspective, the German policy is a government boondoggle. “It’s not surprising that if you throw enough money at a certain technology, people will use it,” says Severin Borenstein, codirector of the Energy Institute at UC Berkeley’s Haas School of Business. Yes, the incentives triggered a frenzy of renewable-power installations, but at “very high prices,” says Henry Lee, director of the Environment and Natural Resources Program at Harvard’s John F. Kennedy School of Government. The spending on photovoltaics has been especially cost-inefficient in terms of producing power, Lee adds, because “Germany is the cloudiest country in Europe.” Despite the weather, Germany now accounts for half the world’s 20 gigawatts of installed solar capacity. “What that gets you,” says Lee, “is high prices for electricity, locked in for 20 years, from technology that will be out of date within three years.” Concludes ­Borenstein: “That’s a failure of public policy.”

As for the job-creation benefit, it may turn out to be ephemeral. Solar panels and wind turbines can be manufactured nearly anywhere in the world. Now, partly because of competition from low-cost manufacturing in China (see “Solar’s Great Leap Forward,” p.52), many German manufacturers of this technology are struggling. Q-Cells, Conergy, and Solarworld have seen their stock lose much of its value since the start of 2008. Anton ­Milner, the founding CEO of Q-Cells, resigned in March after the company reported an annual loss of 1.36 billion euros ($1.67 billion). In May, to keep pace with the plunging cost of solar panels, the Bundestag cut the rates it set for selling solar power to the grid by 11 to 16 percent on top of a scheduled annual decrease of 10 percent. To try to compete with imports, solar companies have fired hundreds of workers, and the nation’s solar trade association has warned of even more layoffs.

Meanwhile, some of the countries that copied key features of the German policy have also seen their booms start to fizzle. In 2008, Spain set an all-time record for photo­voltaics, installing 2.46 gigawatts’ worth of solar panels in a single year–41 percent of all new installation worldwide, according to Solarbuzz, a research and consulting firm. But in Spain, buying all that high-priced power became a burden to the utilities. That, along with a longer contract term and aggressive pricing, caused the tariffs to be drastically cut. Without the high incentives, in 2009 Spain installed only 6 percent of the world’s new solar-power capacity.

Nevertheless, interest in feed-in tariffs is growing in the United States. At least two cities–Sacramento, CA, and Gainesville, FL–have enacted local plans. California, Hawaii, and Vermont have passed laws that would create their own feed-in tariffs, and at least 15 other states have considered it.

What might these policies cost? In Germany, electricity prices have soared more than 60 percent over the past decade. But Germany’s environmental ministry says the tariff system is responsible for less than a 10th of that increase, or about $3 per month for a typical household. Since German households consume about half as much electricity as U.S. homes, the extra cost for renewable energy has not been a deal-breaker for the public, says Kemfert, who contends that a majority of Germans support it. Overall, the tariff cost Germany an estimated $11 billion in 2008 alone, about a third of 1 percent of its GDP.

But why even bother with feed-in tariffs? Many economists favor either a carbon tax or a cap-and-trade system in which electricity plants buy permits to burn fossil fuel. “It would be better to tax brown power than subsidize green power,” says Borenstein. Coal is the biggest carbon emitter among all energy sources, and it currently accounts for about half the electricity produced in the United States as well as in Germany. Phasing out coal should be the main goal, and pursuing that goal by putting a price on carbon, he says, allows the market to decide which renewable sources are most cost-effective. That’s more efficient than letting the government set prices.

However, neither cap-and-trade nor a direct tax may be politically feasible in the United States. So would a national feed-in tariff be an acceptable alternative? Or would it also be politically doomed, since it, too, would raise electricity prices? To make a case for it, politicians would need to convince the American public that renewable power is worth it, pointing to Germany as the example. Indeed, the German experiment does show that a large industrial society can reach ambitious goals for scaling up new sources of clean electricity, with users paying the way. Germany expects to produce most of its electricity from renewable sources by 2030. Meanwhile, the United States produces only about 7 percent of its electricity from such sources, most of that from long-standing hydroelectric plants.

The real significance of the German plan, though, may not be as a model for other countries but as a source of permanent change in the world’s energy economy. In this sense, Germany can be compared to early adopters of new gadgets, who often pay outrageous prices even though they know that others will get improved technology for much less a few years later.

Consider the changes in the market for wind power. By 2006, Germany had by far the largest wind-power base in the world, with 20.6 gigawatts of capacity. The massive scale brought the cost down, and wind began approaching grid parity in many parts of the world. In 2009, the United States and China were able to surpass Germany in capacity, but at far more attractive prices.

Thanks in part to the Germans, the same thing now appears to be happening in solar, with prices of photovoltaic panels plunging 40 percent last year alone. Yes, the critics are right that Germany’s spending was wildly inefficient. But what Germany did was prime the global markets, showing that renewable technologies can be a big business worthy of investment. As a result, the United States may not need to copy Germany’s experiment to reap the rewards.

Evan I. Schwartz is an author and journalist. He produced and cowrote Saved by the Sun, a PBS/NOVA documentary featuring a segment about the German solar policy.

Source.

To see the future of solar power, take an hour-long train ride inland from Shanghai and then a horn-blaring cab trek through the smog of Wuxi, a fast-growing Chinese city of five million. After winding through an industrial park, you will arrive at the front door of Suntech Power, a company that in the few years since its founding has become the world’s largest maker of crystalline-silicon solar panels.

Solar panels cover the entire front face of the sprawling eight-story headquarters. Nearly 2,600 two-meter-long panels form the largest grid-connected solar façade in the world. Together with an array of 1,800 smaller panels on the roof, it can generate a megawatt of power on a sunny day. It’s expected to produce over a million kilowatt-hours of electricity in a year–enough for more than 300 people in China.

In 2001, when Suntech was founded, all the solar-panel factories in China operating at full capacity would have taken six months to build enough panels for such a massive array. Suntech’s first factory, which opened in 2002, cut that time to a little more than a month. Today, the company can make that many panels in less than one 12-hour shift. By the end of this year, the workers could be done by lunchtime. Suntech’s production capacity has increased from 10 megawatts a year in 2002 to well over 1,000 megawatts today. Chinese solar manufacturing as a whole has increased its capacity from two megawatts in 2001 to over 4,000 megawatts.

That rapid growth, fueled by relentless cost cutting, has allowed Chinese manufacturers to overtake those in the United States, Japan, and Germany in less than a decade to become the biggest source of solar panels in the world. Worldwide, Chinese solar panels accounted for about half of total shipments in 2009. And that share is expected to grow this year. Of the 10 largest solar-panel manufacturers, half are based in China. In 2007, U.S.

manufacturers supplied 43 percent of the panels for a solar rebate program in California. The rest came almost exclusively from Japan and Germany; only 2 percent came from China. Now Chinese companies supply 42 percent of the panels, and the U.S. share has dropped to 15 percent according to an analysis by Nathaniel Bullard of Bloomberg New Energy Finance.

In 2004, it cost about $3.20 per watt, on average, to make silicon solar panels. By now, according to solar-industry analysts at Photon Consulting in Boston, a Chinese manufacturer can make them for as little as $1.28 per watt, while the lowest-cost Western manufacturer will produce comparable technology for about $2.00 per watt. Not only has this cost advantage made Chinese manufacturers dominant in the industry, but it’s also helped redefine the prospects for solar power, pushing it closer to what insiders call “grid parity”–the point where it is just as cheap as electricity on the power grid, most of which is generated with fossil fuels. “In about five years’ time, we should be able to reach grid parity in at least 30 to 50 percent of the global market,” says Zhengrong Shi, Suntech’s founder and CEO, speaking from his spacious office looking out over the back of his company’s massive solar façade.

Suntech’s strategy so far has been to cut the cost per watt by reducing the expense of manufacturing solar panels. But reaching grid parity will also require increasing the efficiency of the panels so that each one produces more watts.

Under the leadership of Shi, who was a solar researcher before he became a businessman, the company has developed a new way to make solar panels; multi­crystalline modules made last year broke a 15-year-old record for efficiency in converting sunlight to electricity. A few months later, Suntech increased the efficiency mark yet again. And the company’s lab has prototypes that promise even better results. If these advances pan out, it could finally clear the way for Shi’s dream of affordable solar power.

Riches and Rags

In many ways, Shi reflects the complexity of contemporary China. Though he was born and grew up less than 100 kilometers from his factories in Wuxi, he began his career in Australia, where he lived for a decade and became a citizen before returning to China in 2000 to take advantage of the country’s economic boom. “I have to get a visa to work in China,” Shi says with a hint of an Australian accent, laughing. Despite his wealth and executive position, he has the casual but confident air of a researcher, wearing a simple sports coat and open-collar striped shirt. But his relaxed look and easygoing Australian mannerisms belie his ambition and his close connections to his native country. Several copies of magazine covers featuring him as the “Sun King” (Forbes Asia) and “China’s New King of Solar” (Fortune) are arranged carefully around his spacious office, amid citations from national

academies and other awards. Greeting visitors in the entryway is a huge version of the Ch’an Chu, the Chinese symbol of prosperity–a stone toad gripping a coin the size of a dinner plate in its mouth.

The figure, which is also a symbol of luck, is appropriate. In 2005, when oil prices were volatile and many countries, particularly in Europe, were pushing to cut carbon dioxide emissions, Shi took Suntech public on the New York Stock Exchange. In 2006 he became the seventh-richest man in China, with a net worth of over $1.4 billion, according to Forbes. But the man who made Suntech possible very nearly didn’t get into solar at all.

Shi’s parents, rural farmers left destitute by famines that plagued China in the early 1960s, were forced to give him up for adoption to a close family friend when he was a small child. He excelled at school, ultimately earning a bachelor’s degree in optical science and a master’s in laser physics. Shi applied to study abroad, as many talented students did in China in the late 1980s. He was approved–not for studies in the United States, as he’d expected, but in Australia. Knowing little about the country, he relied on a suggestion from one of his colleagues that he meet Martin Green, the director of the Photovoltaics Centre of Excellence at the University of New South Wales, who was famous for inventing an approach to silicon solar cells that achieved record efficiencies. He applied for a paid research position, but Green “immediately turned me down,” Shi recalls. Instead, Green persuaded him to study for a PhD. He completed the degree in only two and half years, and in 1995 he started work at Pacific Solar, a startup spun out of Green’s lab that was commercializing a new type of thin-film solar cell.

By 2000, Shi was executive director of the startup, but news about the solar industry’s growth in Europe and Japan made him impatient. “I saw the opportunity of solar booming,” he says. Meanwhile, Pacific Solar’s technology was taking too long to bring to market. “Thin-film at that stage was not quite ready yet,” Shi says. He also saw an opportunity in China, where costs were low and no one “really understood the technology and the industry.” After 10 years abroad, he returned to China and presented a business plan to politicians in charge of the Wuxi New District, a high-tech industrial park about an hour from where he’d grown up. His plan was to make conventional silicon solar panels and do it cheaply. Government officials turned him down, suggesting that even his conservative approach was “one step early,” he recalls. Although venture capitalists and large companies offering joint ventures are common now in China, they were rare at the time. So Shi spent the next 10 months making connections and courting politicians while he, his wife, and their two young children lived off his savings. “The real challenge was convincing local government officials that I could succeed in the solar business and not just in the solar laboratory,” he says. Eventually they offered him $6 million, collected from local state-run businesses, to start Suntech.

Shi kept an eye out for every opportunity to cut costs. He bought used equipment. He helped a Japanese company design a new machine in exchange for a discount. And where he could, he found ways to replace machines with cheaper labor.

The manufacturing methods Shi used to get the company off the ground can still be seen in the factory, which is accessible through doors at the back of the headquarters building. Workers, rather than the expensive robots used in solar factories in Japan and the West, transfer eggshell-thin silicon wafers one by one onto racks that can withstand blazing furnaces where temperatures reach 1,000 °C. The operation could be automated, but human labor costs less and can reduce breakage rates. Machines are used where they’re worth it: at another station, one tests the power output of finished cells with a flash of light before robotic arms place them into bins according to performance. A human crew sorts those cells further, identifying fine gradations in the deep blue color. (All this sorting is done to ensure the consistency of the cells that go into a panel.) In another building, workers weld solar cells together into strips, then align them by eye on a light box to form the rows and columns of cells that make up a complete solar panel. To finish the panels, pairs of workers glue the frames together by hand and clean them off with a rag.

On Demand

When Shi started Suntech in 2001, his timing couldn’t have been better. Solar manufacturing in

China was almost nonexistent, so he had little domestic competition. At the same time, the market worldwide was starting to grow. Price incentives for solar power that the German parliament authorized in 2000 were just going into effect (see “The German Experiment“); after those subsidies were increased in 2004, Germany became the world’s largest market for solar panels and Suntech’s biggest source of revenue.

As other governments introduced their own incentives for installing renewable sources of energy, demand soared, and builders began taking a chance on the cheap solar panels coming out of China. “In 2005 and 2006, I couldn’t get solar panels,” says Barry Cinnamon, CEO of Akeena Solar, a solar installer and one of Suntech’s first customers in California. “Demand was way bigger than supply. Any company, anywhere in the world, that could make a piece of glass with wires on it that generated electricity when the sun hit it could sell as many as they wanted.” Not only could Suntech meet his demand, but it was willing to accommodate Akeena’s requests. “What was interesting about Suntech was they were willing to build a specially designed solar panel for us,” he says. “Nobody else would do it.”

In the years after Shi founded Suntech, the total number of watts produced by the solar industry doubled roughly every two years. Suntech stayed ahead of the curve, doubling its own production on average every year until 2009, when the recession slowed things down. This year its production is likely to grow by 100 percent yet again; the company will employ 12,000 workers. The government recently made Suntech eligible for $7.3 billion in loans through the Chinese Development Bank to fund even more expansion.

Meanwhile, hundreds of other solar companies have been founded in China, and several have become major suppliers worldwide. Yingli Green Energy, based near Beijing, has an even bigger share of the California market than Suntech, though it produces fewer panels overall. It also has even lower costs. Others, such as JA Solar, Trina Solar, and China Sunergy, are rapidly gaining brand recognition worldwide. Much of the industry can be traced back to Green and his lab in New South Wales; former students of his are key leaders in companies that together produce 60 percent of the solar panels made in China. But if Green supplied much of the technical training, he credits Shi with the business savvy to help create the nation’s booming industry. “Former students have had a big impact in China,” he says. But, he adds, “I would give all the credit to Zhengrong Shi for blazing the trail the others have followed.”

Green Tricks

When he founded Suntech, Shi knew that it was possible to manufacture solar cells nearly twice as powerful as the ones that rolled off the line of his first factory. Green had been making them for years in his lab. If you alter the electronic properties of the very highest-grade silicon wafers in precise patterns and then trace extremely fine electrical contacts on their front and back surfaces to extract electronic current, the resulting cells capture much more of that current than conventional cells do. The only problem is that Green’s methods rely on advanced and expensive processing technology borrowed from the semiconductor industry. The cells cost about 100 times as much to make as conventional solar cells like the ones Suntech has been producing so far.

The University of New South Wales had been trying unsuccessfully to commercialize the technology for 20 years, but Shi was determined to find a way. The key was to identify low-cost methods of achieving the same effects with readily available, commercial-­grade silicon. Pointing to its 45 patents and 65 pending patents, Suntech claims it has now succeeded, but it’s secretive about the details. Only three employees have seen the whole process of making its new products. “We know that anyone who has seen the entire line will be targeted very, very enthusiastically by other companies,” says Stuart Wenham, Suntech’s chief technology officer. Wenham, a colleague of Green’s at New South Wales and of Shi’s at Pacific Solar, was brought in to Suntech in 2005 to produce the advanced cells. “Dr. Shi was so determined to keep all of this confidential that he bought his own equipment company to make the equipment for this technology,” he says.

The process involves replacing a key step in making conventional solar cells: screen printing. To extract electrical current from a cell, manufacturers print lines of silver paste on its front surface. The closer together these electron-

conducting lines are, the more efficiently they’ll collect charge from the silicon. If too much of the cell’s surface is shaded by the lines, however, the cell can’t absorb enough light. The thinner the lines are, the closer they can get without causing this problem, but the printing process can’t make them thinner than about 120 micrometers.

The Suntech researchers developed a way to chemically treat the silicon wafer in narrow bands. These treated areas attract silver, which forms metal lines just 20 micrometers wide. In addition to resulting in thinner lines, the process makes it possible to save material costs by using wafers of silicon so thin that screen-­printing equipment might break them as it stamped the lines on their surface. It also replaces a treatment used in conventional manufacturing that reduces the cells’ efficiency by damaging the surface of the silicon. The best modules made with the new technology convert about 18 percent of the energy in light into electricity–as opposed to 13 percent for the company’s original solar panels. Next year Suntech intends to roll out a newer version of the technology, which preliminary tests suggest will improve efficiency by another one or two percentage points. The improvement might seem modest, but increased efficiency has a big impact on the cost of the resulting electricity. As a rule of thumb, a percentage-point improvement in efficiency can cut costs by over 6 percent.

Suntech is also funding collaborations with universities, including New South Wales and Swinburne University of Technology in Melbourne, to develop solar cells that get around a fundamental limitation of today’s photovoltaics: they can’t absorb all the wavelengths in sunlight, and they can’t convert all the energy in many of those wavelengths into electronic charge. One key investment is in plasmonics, which makes use of the fact that metal particles deposited on a cell’s surface can guide light energy so that it bounces back and forth within the cell instead of being reflected back out. Exploiting this effect could enable researchers to reduce the amount of active semiconductor material in a solar cell by orders of magnitude, or even to make cells out of materials far cheaper than purified, crystalline silicon (see “Light-Trapping Photovoltaics,”May/June 2010). “Those concepts will probably not find their way into commercial products in the next 10 to 20 years,” Wenham says. “But they will eventually.”

On the Verge

In spite of the rapid growth of Suntech and the solar industry worldwide, solar power still contributes a vanishingly small portion of the total electricity produced each year. In the United States, it’s slightly above 0.1 percent. “It’s a rounding error,” says Nathaniel Bullard, an analyst for Bloomberg New Energy Finance.

It’s hard to project the course of the still tiny industry. For one thing, all predictions of when solar power might reach grid parity are rife with uncertainties, Bullard says. To take just one example, consider that today the solar panels themselves account for less than half the total cost of the technology. The costs of installation, additional equipment such as inverters, sales and marketing by installers, and, crucially, financing will also need to come down. What’s more, when it comes to grid parity, the price that photovoltaics manufacturers charge for their products is actually more significant than the money it costs to make them–and that will depend on the market. If demand for photovoltaics remains high, in part because government incentives in Germany and elsewhere prop it up, then solar panels could remain expensive enough to keep the price of solar energy well above that of electricity from the grid.

It’s also not yet clear what technology is best suited for widespread use of solar power. Ten years from now, the solar panels most people buy might not even be made of silicon. Switching would be hard for Suntech. While it has the expertise to change direction, its low manufacturing costs depend on investments in equipment and agreements with silicon suppliers. Meanwhile, rival companies have a head start on the technologies that use other materials. First Solar, based in Tempe, AZ, makes thin-film solar cells made of cadmium and tellurium for even less per watt than the Chinese companies making silicon cells. Admittedly, First Solar’s technology converts only about 11 percent of sunlight into electricity; that relatively low efficiency translates into higher installation costs and limits the applications it’s good for. Still, thin-film solar is accounting for a steadily greater share of the overall market, from 3 percent in 2003 to more than 15 percent today.

Yet for all this uncertainty, Shi remains convinced that silicon-based solar power is on the verge of becoming competitive without government subsidies. The idea that solar energy will have to wait for a breakthrough to reach grid parity is “crap,” he says. He adds: “We’re not talking about rocket science. We’re talking basic engineering.”

By Kevin Bullis.

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A simplified process for printing polymer solar cells could further reduce the costs of making the plastic photovoltaics. The method, which has been demonstrated on a large-area, roll-to-roll printing system, eliminates steps in the manufacturing process. If it can be applied to a wide range of polymer materials, it could lead to a fast and cheap way to make plastic solar cells for such applications as portable electronics, photovoltaics integrated into building materials, and smart fabrics.

Polymer solar cells aren’t as efficient as silicon ones in converting sunlight into electricity, but they’re lightweight and cheap, a trade-off that could make them practical for some applications. And they’re compatible with large-area printing techniques such as roll-to-roll processing. But manufacturing the solar cells is challenging, because if the polymers aren’t lined up well at the nanoscale, electrons can’t get out of the cell. Researchers now use post-printing processing steps to achieve this alignment. Eliminating these extra steps will, University of Michigan researchers hope, bring down manufacturing costs and complexity.

“Our strategy solves a number of issues at the same time,” says L. Jay Guo, professor of electrical engineering at the University of Michigan. Their process involves applying a small amount of force during the printing process with a permeable membrane. The process allows the printing solvents to evaporate and leads to well-ordered polymer layers–without any need for post-processing. These improvements in the structure of the cell’s active layer have an additional benefit: cells made using this technique require one fewer layer of materials than polymer solar cells made using other methods. This work is described online in the journal Advanced Materials.

When light of a certain wavelength strikes the semiconducting material in a solar cell, it creates electrons and positively charged holes. To generate an external current, the cell must separate the electrons from the holes so that they can exit. This separation doesn’t happen as readily in polymers as it does in inorganic materials like silicon, says Guo. The active layers in polymer solar cells combine two materials, one that conducts holes and one that conducts electrons. Ideally the electron-accepting polymer would be on top of the electron-donating polymer, so that it’s near the cathode, allowing as many electrons to exit as possible.

Guo’s group found that spreading the polymer mix onto a plastic substrate, then pressing it against a roller coated with silicone, facilitates the formation of this desirable structure. And the pressure from the roller encourages the polymers to crystallize in a matter of seconds, without the need for the time-consuming chemical or thermal treatments. The structure of the polymers is so good, says Guo, that the Michigan researchers could eliminate a layer from the cells without any change in power-conversion efficiency.

So far, Guo has used a common but relatively low-efficiency polymers to fabricate the solar cells, but he says the method should be compatible with higher efficiency polymer materials. The Michigan cells have an efficiency of only about 3.5 percent. Researchers are working on materials sets that should bring the efficiencies of polymer solar cells up to 12 to 15 percent, a boost that’s necessary if polymer solar cells are to reach a broad market and more fully compete with conventional silicon and thin-film cells.

“I think this process has very strong potential,” says Yang Yang, professor of materials science and engineering at the University of California, Los Angeles. “It’s uncertain whether this method also works for other polymer systems, but there is no reason why it won’t.” Yang is collaborating with plastic solar-cell company Solarmer of El Monte, CA, which is on track to reach 10 percent efficiency with its devices by the end of this year.

By Katherine Bourzac

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Thanks to these efforts, the cost of photovoltaic modules has dropped 40 percent in the last 18 months. Photovoltaic electricity now costs about 15 cents per kilowatt-hour in the best sunlight. That’s only twice the cost of wholesale electricity and wind. Costs are expected to continue decreasing, and electricity is worth more during the daytime than at night. That means this technology is finally cheap enough to become a significant element in plans to combat climate change and oil dependence.

The advantages of solar panels are clear. They need no fuel or water, and sunlight is nearly limitless. With 100 times the energy potential of wind, sunlight is sufficient to meet all our energy needs. Photovoltaic panels are also unique for their long, low-cost operating life–now 30 to 40 years, someday perhaps 100. And unlike energy sources that require a constant input of fuel, photovoltaic electricity is almost free once its initial capital cost is recovered.

In 2008, when the U.S. Department of Energy drafted a report looking at the potential for “20 percent wind energy by 2030,” the plan called for only 5 percent of the country’s energy to come from solar power. Soon, the department will publish a new “solar vision” examining the potential for a plan incorporating 10 percent solar photovoltaics, 10 percent solar thermal, and 10 percent wind by the same year. Meanwhile, further DOE work will look at a goal of deriving 80 percent of our energy from renewable sources in 2050. The European Climate Foundation has released a study with McKinsey showing that renewables could produce 100 percent of European electricity by that date. The reports maintain that reaching these targets will have minimal impact on electricity prices.

The ingredients for a fully green solution to climate change and oil dependence are in our grasp. They include electricity from wind and solar photovoltaics; electric vehicles to get us off gasoline; smart grid and transmission technologies to distribute solar and wind power and to balance supply with demand; and domestic natural gas to fill in the gaps. We don’t have to turn Earth’s crust into a carbon-sequestration experiment, increase our risks with nuclear, or convert arable land to energy farming. We are on track to deploy safe, renewable technologies to stabilize the price of oil and dial down carbon dioxide emissions as much as we want. Confirming photovoltaics’ place among these technologies is a big step in the right direction.

Ken Zweibel is director of the GW Solar Institute at George Washington University.

By By Ken Zweibel.

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If I succeed, I will have a lucid dream – a thrilling state of consciousness somewhere between waking and sleeping in which, unlike conventional dreams, you are aware that you are dreaming and able to control your actions. Once you have figured this out, the dream world is theoretically your oyster, and you can act out your fantasies to your heart’s content.

Journalistic interest notwithstanding, I am pursuing lucid dreaming for entertainment. To some neuroscientists, however, the phenomenon is of profound interest, and they are using lucid dreamers to explore some of the weirder aspects of the brain’s behaviour during the dream state (see “Dream mysteries”). Their results are even shedding light on the way our brains produce our rich and complex conscious experience.

It’s a central issue in the study of consciousness. In 1992, Gerald Edelman at the Scripps Research Institute in La Jolla, California, proposed that there are two possible states of consciousness, which he called primary and secondary consciousness. Primary consciousness is the simple subjective experience of sensory perception and emotions, which could be applied to most animals. It’s a state of “just being, feeling, floating”, according to Ursula Voss at the University of Frankfurt in Germany.

The mental life of your common or garden human, however, is a lot more complicated. That’s because we are “aware of being aware”. This allows us to reflect upon ourselves and our feelings and, in an ideal world, make insightful decisions and judgements. This state, dubbed secondary consciousness, is thought to be unique to humans.

“When you’re awake, you have both primary and secondary consciousness. Secondary consciousness is that reflective awareness that determines a great part of waking consciousness,” says Voss.

Pinning down how our brain produces these two, subjective, states of consciousness is a tough challenge, because it’s difficult to isolate the different aspects of consciousness in fully awake subjects from other neural processes unrelated to awareness.

Which is where dreams come in. When we dream, we experience events (albeit imagined) and emotions but, crucially, we lack certain aspects of self-awareness that we normally feel when we are awake, particularly those involved in the rational reflection on what we are experiencing. You could easily see an outrageous event – a fluorescent pink kitten flying past on golden wings, to name but one – without batting a dream eyelid. “If we can accept really weird and bizarre events as perfectly normal happenings, that means there’s something wrong with our reflective, rational consciousness,” says Patrick McNamara of Boston University.

For this reason, some researchers, like Allan Hobson at Harvard Medical School, believe that dreams are akin to Edelman’s definition of primary consciousness. Comparing the dream state with the waking state could let us explore the way the brain generates the self-awareness of secondary consciousness.

Some headway had already been made in this direction by the late 1990s. In 1997, Eric Nofzinger and his colleagues at the University of Pittsburgh, Pennsylvania, compared the brain activity of awake individuals with dreamers using PET scans, which reveal how much energy parts of the brain are using. The team identified three main regions that showed more activity during dream sleep, which is characterised by rapid eye movement (REM). The areas were along the midline of the brain, the insula and the left amygdala. Together, these regions are thought to be involved in motivation and reward mechanisms, and processing emotions, which Nofzinger reckons might explain why dreams are often so emotional.

Surprisingly, given the irrationality of the dream experience, many of the frontal areas of the brain involved in advanced cognition such as reasoning and forward planning were also active in the dreamers. But there was one notable exception: the dorsolateral prefrontal cortex (DLPFC) was remarkably subdued in REM sleep, compared with during wakefulness. To Hobson, that strongly suggests that this particular area, above other frontal regions, is crucial for the critical reflective awareness present in waking, and therefore secondary, consciousness (Trends in Cognitive Sciences, vol 6, p 475).

Could this one brain region alone explain our secondary consciousness? It’s here that lucid dreams enter the picture. With their increased self-awareness, lucid dreams share certain aspects of secondary consciousness, so researchers are now vying to observe what happens in the brain when someone “wakes up” within their dream, and whether they exhibit any further signatures of consciousness. “It’s a very interesting leap because it can show you exactly what occurs if you jump from limited consciousness to very high consciousness,” says Victor Spoormaker of the Max Planck Institute of Psychiatry, Munich, Germany. “This should be one of the main themes of lucid dream research.”

Lucidity on demand

Voss and her colleagues made tentative steps towards using lucid dreams to study consciousness in 2009. She trained a group of students to become lucid dreamers using a number of tips and tricks (see “Lessons in lucidity”). Once they had “woken up” within their dream, the subjects were then asked to signal to Voss that they were lucid by moving their eyes in a previously agreed pattern, which was measured with an electro-oculograph. “We have no other way of knowing they’re really in a lucid dream,” says Voss. “It’s a great effort to make these eye movements because normally you’re in that dream and you’re busy with other things; you don’t want to communicate with the outside world.” At the same time, Voss used EEG – a cap of electrodes placed on the scalp – to record their brain activity.

Unfortunately, the team only managed to capture three lucid dreams, an indication of just how tricky they are to study. But it was enough to reveal a couple of intriguing differences between the lucid and non-lucid dreaming brain that may contribute to the secondary state of consciousness. Firstly, the team observed an increase in a specific brainwave – oscillating at 40 hertz – in the frontal regions during the lucid dreams compared to the non-lucid dreams, which tended to have slower brain waves. They also found greater synchronised activity between the frontal and parietal regions of the brain than in normal REM sleep, though less than would be expected in a fully awake subject (Sleep, vol 32, p 1191). Importantly, the overall brain activity was still significantly different to the waking state, meaning the subjects couldn’t have been awake and simply pretending to lucid dream (see diagram).

What was the DLPFC up to? If it really were key to the self-awareness of secondary consciousness, you would expect it to “light up” during the lucid dreaming state. Unfortunately, EEG is not sensitive enough to measure the neural activity in such a small, specific area. However, preliminary work by Michael Czisch at the Max Planck Institute of Psychiatry in Munich, Germany, hints at the answer. He used high-resolution fMRI scans to investigate the brain state of lucid dreamers. Although the results are currently being peer-reviewed, so many of the details are still under wraps, Czisch has hinted that the scans again reveal highly coordinated activity in the frontal regions of the brain, and also in the parietal and temporal zones, once the dreamers became lucid. The DLPFC was also more active than in a usual REM dream – providing tantalising evidence that it really is a crucial ingredient of secondary consciousness.

The million dollar question, of course, is how these specific patterns of electrical activity could give rise to our conscious experience. The DLPFC’s role certainly makes sense, given laboratory studies that have shown it retrieves and analyses information in our working memory, and that it plays a key part in decision making.

What of the other signatures of lucidity? The coordinated neural activity may help the various brain regions communicate more effectively, “binding” together all the different thoughts and feelings being processed separately across the brain into a single unified experience, which we perceive as “the present”. One might expect more binding – and therefore greater synchrony – in secondary consciousness compared with primary consciousness, simply because the experience is so much richer, combining analytical thoughts as well as sensory perceptions and emotions.

The specific frequency of much of the neural activity in the frontal areas – 40 hertz – is also significant. Slower frequency brain waves usually dominate in sleep, whereas 40 hertz waves are more characteristic of the waking state, suggesting secondary consciousness will only emerge if the relevant neurons are communicating at a fast enough rate. Hobson likens it to “turning up the volume” in the brain.

These experiments in lucid dreaming, few though they currently are, may have wide-reaching implications in clinical situations, particularly in the study of mental illness. “When you’re a schizophrenic, you’re in primary consciousness really,” Voss claims. “What you’re lacking is reflective awareness; you cannot distinguish between reality and your hallucinations.” On this basis, Voss wonders whether it might be possible to stimulate the necessary regions in schizophrenic patients to help them achieve greater lucidity in their waking life. The work might even suggest ways for healthy people to enjoy lucid dreams. “Wouldn’t it be nice if you could get somebody in REM sleep to become a lucid dreamer just by stimulating his brain?” says Voss. “No one’s tried this before.”

Luckily for me, I have been able to make my first foray into this strange state of consciousness without any artificial stimulation. I’m happy to report that on a sunny morning over the Easter weekend, I had my first lucid dream. It lasted all of a few seconds, and I was merely able to consciously twirl on the spot, but I woke up excited and happy. With the whole dream world now open to me, let’s just hope this is only the start of my lucid life.

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The equivalence principle is one of the corner stones of general relativity. Now physicists have used quantum mechanics to show how it fails.

The equivalence principle is one of the more fascinating ideas in modern science. It asserts that gravitational mass and inertial mass are identical. Einstein put it like this: the gravitational force we experience on Earth is identical to the force we would experience were we sitting in a spaceship accelerating at 1g. Newton might have said that the m in F=ma is the same as the ms in F=Gm1m2/r^2.

This seems eminently sensible. And yet it is no more than an assertion. Sure, we can measure the equivalence with ever increasing accuracy but there is nothing to stop us thinking that at some point the relationship will break down. Indeed several modifications to relativity predict that it will.

One important question is what quantum mechanics has to say on the matter. But physicists have so far been unable to use quantum theory as a lever to tease apart the behaviour of inertial and gravitational mass.

All that changes today with the extraordinary work of Endre Kajari at the University of Ulm in Germany and a few buddies. They show how it is possible to create situations in the quantum world in which the effects of inertial and gravitational mass must be different. In fact, they show that these differences can be arbitrarily large.

Their thinking begins by pointing out the important distinction between kinematics, which is concerned purely with motion not how it arises, and dynamics which focuses on the origin of motion. In the classical world, this has no bearing on the effects of inertial and gravitational mass.

However, in the quantum world, the way states are prepared has huge significance. They point out, for example, that the wave function of a particle in a box does not depend on mass at all whereas the energy wave function of a harmonic oscillator depends on the square root of the mass.

That leads to an interesting idea: that it is possible to create combinations of gravitational and electromagnetic boxes and oscillators in which inertial and gravitational mass play different roles.

It turns out that physicists already play with exactly this kind of set up: the so-called atom trampoline, in which a matter wave falls under the influence of gravity but is bounced by an electromagnetic force. They calculate that the energy eigenvalues of the atom are proportional to the (gravitational mass)^2/3 but to the (inertial mass)^-1/3.

That’s an amazing result. The kind of energy spectroscopy of atoms or Bose Einstein Condensates that can spot this difference ought to be achievable, if not now, then very soon within the next few years.

If successful, these kinds of investigations will provide an entirely new way of studying the nature of mass and, perhaps more importantly, of investigating the puzzling relationship between general relativity and quantum mechanics.

For example, cosmologists will want to know how inertial and gravitational mass behaves in the most extreme conditions in the Universe, such as inside black holes.

That promises an exciting few years ahead.

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Acupuncture’s scientific credentials are growing. Trials show that it improves sensory and motor functions in people with spinal cord injuries.

To find out why, Doo Choi and his colleagues at Kyung Hee University in Seoul, South Korea, damaged the spines of 75 rats. One-third were given acupuncture in two locations: Shuigou – between their snout and mouth, and Yanglingquan – in the upper hind leg. Others received no treatment or “simulated acupuncture”.

After 35 days, the acupuncture group were able to stand at a steeper incline than the others and walk better. Staining their paws with ink revealed that their forelimb-hindlimb coordination was fairly consistent and that there was very little toe dragging, whereas the control groups still dragged their feet.

Inflamed spines

The rats in the acupuncture group also had less nerve cell death and lower levels of proteins known to induce inflammation after spinal cord injury and make neural damage worse.

One explanation is that sharp needles prompt a stress response that dampens down inflammation. In humans, the inflammation that follows spinal cord injury is known to be responsible for nerve cell death.

Zhen Zheng of the Royal Melbourne Institute of Technology in Australia says the results are “very encouraging”. But she says we don’t yet know if the results will apply to humans.

For example, the acupuncture treatment on the rats was given almost immediately after injury, but most patients don’t seek acupuncture until at least three months after damage to their spines.

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Molecular biology and genetics have driven the biosciences, but have not given us the miraculous new insights we were led to expect. From professional biologists to schoolchildren, people are concentrating on the minutiae of what goes on in the deepest recesses of the cell. For me, however, this misses out on life in the round: it is only when we look at the living cell as a whole organism that wonderful realities emerge that will alter our perception not only of how single cells enact their intricate lives but what we humans truly are.

The problem is that whole-cell biology is not popular. Microscopy is hell-bent on increased resolution and ever higher magnification, as though we could learn more about animal behaviour by putting a bacon sandwich under lenses of increasing power. We know much about what goes on within parts of a cell, but so much less about how whole cells conduct their lives.

Currently, cell biology deals largely with the components within cells, and systems biology with how the components interact. There is nothing to counterbalance this reductionism with a focus on how whole cells behave. Molecular biology and genetics are the wrong sciences to tackle the task.

Let’s take a look at some of the evidence for ingenuity and intelligence in cells that is missing from the curriculum. Take the red algae Rhodophyta, in which many species carry out remarkable repairs to damaged cells. Cut a filament of Antithamnion cells so the cell is cut across and the cytoplasm escapes into the surrounding aquatic medium. All that remains are two fragments of empty, disrupted cell wall lying adjacent to, but separate from, each other. Within 24 hours, however, the adjacent cells have made good the damage, the empty cell space has been restored to full activity, and the cell walls meticulously realigned and seamlessly repaired.

The only place where this can happen is in the lab. In nature, the broken ends of the severed cell would nearly always end up remote from each other, so selection in favour of an automatic repair mechanism through Darwinian evolution would be impossible. Yet something amazing is happening here: because the damage to the Antithamnion filament is unforeseeable, the organism faces a situation for which it has not been able to adapt, and is therefore unable to call upon inbuilt responses. It has to use some sort of problem-solving ingenuity instead.

We regard amoebas as simple and crude. Yet many types of amoeba construct glassy shells by picking up sand grains from the mud in which they live. The typical Difflugia shell, for example, is shaped like a vase, and has a remarkable symmetry.

Compare this with the better known behaviour of a caddis fly larva. This maggot hunts around the bottom of the pond for suitable scraps of detritus with which to construct a home. Waterlogged wood is cemented together with pondweed until the larva has formed a protective covering for its nakedness. You might think this comparable to the home built by the testate amoeba, yet the amoeba lacks the jaws, eyes, muscles, limbs, cement glands and brain the caddis fly larva relies on for its skills. We just don’t know how this single-celled organism builds its shell, and molecular biology can never tell us why. While the home of the caddis fly larva is crude and roughly assembled, that of the testate amoeba is meticulously crafted – and it’s all made by a single cell.

The products of the caddis fly larva and the amoeba, and the powers of red algae, are about more than ingenuity: they pose important questions about cell intelligence. After all, whole living cells are primarily autonomous, and carry out their daily tasks with little external mediation. They are not subservient nanobots, they create and regulate activity, respond to current conditions and, crucially, take decisions to deal with unforeseen difficulties.

Just how far this conceptual revolution about cells could take us becomes clearer with more complex animals, such as humans. Here, conventional wisdom is that everything is ultimately controlled by the brain. But cells in the liver, for example, reproduce at just the right rate to replace cells lost through attrition; follicular cells create new hair; bone marrow cells produce new circulating blood cells at a rate of millions per minute. And so on and on. In fact, around 90 per cent of this kind of cell activity is invisible to the brain, and the cells are indifferent to its actions. The brain is an irrelevance to most somatic cells.

So where does that leave the neuron, the most highly evolved cell we know? It ought to be in an interesting and privileged place. After all, neurons are so specialised that they have virtually abandoned division and reproduction. Yet we model this cell as little more than an organic transistor, an on/off switch. But if a red alga can “work out” how to solve problems, or an amoeba construct a stone home with all the “ingenuity” of a master builder, how can the human neuron be so lowly?

Unravelling brain structure and function has come to mean understanding the interrelationship between neurons, rather than understanding the neurons themselves. My hunch is that the brain’s power will turn out to derive from data processing within the neuron rather than activity between neurons. And networks of neurons enhance the effect of those neurons “thinking” between themselves. I think the neuron’s action potentials are rather like a language neurons use to transmit processed data from one to the next.

Back in 2004, we set out to record these potentials, from neurons cultured in the lab. They emit electrical signals of around 40 hertz, which sound like a buzzing, irritating noise played back as audio files. I used some specialist software to distinguish the signal within the noise – and to produce sound from within each peak that is closer to the frequency of a human voice and therefore more revealing to the ear.

Listening to the results reprocessed at around 300 Hz, the audio files have the hypnotic quality of sea birds calling. There is a sense that each spike is modulated subtly within itself, and it sounds as if there are discrete signals in which one neuron in some sense “addresses” another. Could we be eavesdropping on the language of the brain?

For me, the brain is not a supercomputer in which the neurons are transistors; rather it is as if each individual neuron is itself a computer, and the brain a vast community of microscopic computers. But even this model is probably too simplistic since the neuron processes data flexibly and on disparate levels, and is therefore far superior to any digital system. If I am right, the human brain may be a trillion times more capable than we imagine, and “artificial intelligence” a grandiose misnomer.

I think it is time to acknowledge fully that living cells make us what we are, and to abandon reductionist thinking in favour of the study of whole cells. Reductionism has us peering ever closer at the fibres in the paper of a musical score, and analysing the printer’s ink. I want us to experience the symphony.

Profile

Brian J. Ford is a research biologist based at Gonville and Caius College, University of Cambridge.

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Thin-film solar cells, which are made from semiconductor materials like amorphous silicon or cadmium telluride, are cheaper to produce than conventional solar cells, which are made from relatively thick and expensive crystalline wafers of silicon. But they are also less efficient, because if a cell is thinner than the wavelength of incoming light is long, that light is less likely to be absorbed and converted. At just a few micro­meters thick, thin-film cells only weakly absorb wavelengths in the near-infrared part of the spectrum; that energy is lost. The result is that thin-film photovoltaics convert 8 to 12 percent of incoming light to electricity, versus 14 to 19 percent for crystalline silicon. Thus, larger installations are required in order to produce the same amount of electricity, limiting the number of places the technology can be used.

Catchpole, who is now a research fellow at the Australian National University in Canberra, began work on this problem in 2002 at the University of New South Wales in Sydney. “It was a case of ‘start at the beginning: can you think of a completely different way to make a solar cell?’ ” she says. “One of the things I came across was plasmonics–looking at the strange optical properties of metals.”

Plasmons are a type of wave that moves through the electrons at the surface of a metal when they are excited by incident light. Others had tried harnessing plasmonic effects to make conventional silicon photovoltaics more efficient, but no one had tried it with thin-film solar cells. Catchpole found that nanoparticles of silver she deposited on the surface of a thin-film silicon solar cell did not reflect back light that fell directly onto them, as would happen with a mirror. Instead, plasmons that formed at the particles’ surface deflected the photons so that they bounced back and forth within the cell, allowing longer wavelengths to be absorbed.

Catchpole’s experimental devices produce 30 percent more electrical current than conventional thin-film silicon cells. If Catchpole can integrate her nanoparticle technology with the processes used to mass-produce thin films commercially, it could shift the balance of technology used in solar cells. Thin-film photovoltaics could not only gain market share (they currently have just 30 percent of the market in the United States) but sustain growth in the solar industry overall.

Thus far, silicon has been losing out to cadmium telluride as the material of choice for thin-film solar cells. (First Solar, the market leader, is planning gigawatt-scale solar farms that will use cadmium telluride thin-film technology to deliver as much electricity as conventional power stations.) But tellurium is a rare material, and experts question whether the supply will support such grand ambitions. “There just isn’t enough tellurium to make a substantial difference to the way the world’s energy is produced,” says Catchpole. “Silicon is the way to go.”

Catchpole has been approached by companies, but she wants to refine the technology further before commercializing it. Meanwhile, researchers at Swinburne University of Technology in Melbourne are collaborating with Suntech Power, one of the world’s largest manufacturers of silicon solar cells, on plasmonic thin-film silicon cells of their own. The company’s plasmonic photovoltaics are expected to be ready for production within four years.

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Vlasopoulos discovered the recipe for Novacem’s cement as a grad student at Imperial College London. “I was investigating cements produced by mixing magnesium oxides with Portland cement,” he says. But when he added water to the magnesium compounds without any Portland in the mix, he found he could still make a solid-setting cement that didn’t rely on carbon-rich limestone. And as it hardened, atmospheric carbon dioxide reacted with the magnesium to make carbonates that strengthened the cement while trapping the gas. Novacem is now refining the formula so that the product’s mechanical performance will equal that of Portland cement. That work, says ­Vlasopoulos, should be done “within a year.”

Other startups are also trying to reduce cement’s carbon footprint, including Calera in Los Gatos, CA, which has received about $50 million in venture investment. However, Calera’s cements are currently intended to be additives to Portland cement rather than a replacement like Novacem’s, says Franz-Josef Ulm, director of the Concrete Sustainability Hub at MIT. Novacem could thus have the edge in reducing emissions, but all the startups face the challenge of scaling their technology up to industrial levels. Still, Ulm says, this doesn’t mean a company must displace billions of tons of Portland cement to be successful; it can begin by exploiting niche areas in specialized construction. If Novacem can produce 500,000 tons a year, ­Vlasopoulos believes, it can match the price of Portland cement.

Even getting that far will be tough. “They are introducing a very new material to a very conservative industry,” says Hamlin Jennings, a professor in the Department of Civil and Environmental Engineering at Northwestern University. “There will be questions.” Novacem will start trying to persuade the industry by working with Laing O’Rourke, the largest privately owned construction company in the U.K. In 2011, with $1.5 million in cash from the Royal Society and others, Novacem is scheduled to begin building a new pilot plant to make its newly formulated cement.

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Designing the perfect renewable fuel.

When Noubar Afeyan, the CEO of Flagship Ventures in Cambridge, MA, set out to invent the ideal renewable fuel, he decided to eliminate the middleman. Biofuels ultimately come from carbon dioxide and water, so why persist in making them from biomass–corn or switchgrass or algae? “What we wanted to know,” Afeyan says, “is could we engineer a system that could convert carbon dioxide directly into any fuel that we wanted?”

The answer seems to be yes, according to Joule Biotechnologies, the company that Afeyan founded (also in Cambridge) to design this new fuel. By manipulating and designing genes, Joule has created photosynthetic microörganisms that use sunlight to efficiently convert carbon dioxide into ethanol or diesel–the first time this has ever been done, the company says. Joule grows the microbes in photobioreactors that need no fresh water and occupy only a fraction of the land needed for biomass-based approaches. The creatures secrete fuel continuously, so it’s easy to collect. Lab tests and small trials lead Afeyan to estimate that the process will yield 100 times as much fuel per hectare as fermenting corn to produce ethanol, and 10 times as much as making it from sources such as agricultural waste. He says costs could be competitive with those of fossil fuels.

If Afeyan is right, biofuels could become an alternative to petroleum on a much broader scale than has ever seemed possible. The supply of conventional biofuels, such as those made from corn, is constrained by the vast amount of water and agricultural land needed to grow the plants they’re made from. And while advanced biofuels require less water and don’t need high-quality land, their potential is limited by the expensive, multistep processes needed to make them. As a result, the International Energy Agency estimates that in 2050, biodiesel and ethanol will meet only 26 percent of world demand for transportation fuel.

Joule’s bioengineers have equipped their microörganisms with a genetic switch that limits growth. The scientists allow them to multiply for only a couple of days before flipping that switch to divert the organisms’ energy from growth into fuel production. While other companies try to grow as much biomass as possible, Afeyan says, “I want to make as little biomass as I can.” In retrospect, the approach might seem obvious. Indeed, the startup Synthetic Genomics and an academic group at the BioTechnology Institute at the University of Minnesota are also working on making fuels directly from carbon dioxide. Joule hopes to succeed by developing both its organisms and its photobioreactor from scratch, so that they work perfectly together.

Still, it’s a risky strategy, since it departs from established processes. Usually, a startup sets out determined to do something novel, says James Collins, a professor of biomedical engineering at Boston University and a member of Joule’s scientific advisory board, “and it falls quickly back on trying to find something that works … an old thing that’s been well established.” Afeyan, however, has pushed the company to stay innovative. This summer, it will move beyond lab-scale tinkering; an outdoor pilot plant is currently under construction in Leander, TX.

As both a venture capitalist and a technologist–he received his PhD in chemical engineering from MIT in 1987–Afeyan is keenly aware of the challenges in demonstrating that a novel process can operate economically and make fuel in large volumes. To minimize the financial risks, he steered Joule toward a modular process that doesn’t require large and expensive demonstration plants.

“I’m not saying it’s easy or around the corner, because I’ve done this for a long time,” Afeyan says. But he does believe that Joule is onto something big: a renewable fuel that could compete with fossil fuels on both cost and scale. He says, “We have the elements of a potentially transformative technology.”

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The process involves freezing old rubber and shattering it into small particles–resulting in new, low-cost materials.

Of the nearly 300 million tires discarded in the United States each year, more than half end up either as landfill or are burned for fuel in cement kilns and in other industries.

Lehigh Technologies of Tucker, GA, has developed a process for rejuvenating discarded rubber that could open up new recycling opportunities. If the company’s technology catches on, it could carve out a billion-dollar market for high-performance recycled rubber.

Used rubber is hard to recycle because it is vulcanized–hardened and rendered chemically inert–by the addition of sulfur and other compounds to the material’s long molecular chains. Small chunks of used tires can be partially melted and used as filler in asphalt, but devulcanizing rubber involves expensive chemical and thermal processes.

Lehigh Technologies instead shatters rubber into a fine powder using a process that involves freezing old rubber and smashing it to pieces. This starts with tires that have been torn into half-inch chunks using conventional shredding equipment. Lehigh mixes these rubber pieces with liquid nitrogen, cryogenically cooling the rubber to -100°C. The rubber is then fed into a high speed “turbomill” that shatters it into particles no more than 180 microns in size.

Creating such fine powder transforms the rubber from a highly inert filler material to one that can bond with other materials. “We deliver a huge increase in surface area relative to size, and that allows for a much more intimate mixing with other materials,” says Lehigh Technologies CEO Alan Barton.

In 2006, Lehigh Technologies opened its first commercial facility, which has a capacity to produce 100 million pounds of rubber powder and to process four million tires per year. Sales of the company’s products increased by 40 percent last year, but the facility is still operating at less than half capacity. Barton says that his firm has sold recycled rubber to a number of leading tire manufacturers. He estimates that 30 million tires now on the road in the United States are made in part with his company’s recycled rubber, although only about 3 to 7 percent of all the rubber in these tires is their recycled material.

This is largely because Lehigh’s rubber is still technically vulcanized. Carbon atoms in the rubber are still bound to sulfur atoms, and these bonds prevent them from forming covalent bonds with surrounding materials.

The company recently opened an in-house research center that is looking to change the chemical properties of powders it produces, to make their surfaces more reactive. The company has also developed ways to make recycled rubber bind to surrounding materials via noncovalent, intermolecular bonds.

Nearly a third of Lehigh’s annual output also goes to specialty applications, from paints and coatings to injection mold plastics. Lehigh’s PolyDyne and MicroDyne powders can be used to replace as much as 40 percent of the polymers that normally go into plastic.

PolyDyne, the larger and less expensive of Lehigh’s two rubber powders, sells for just under 50 cents a pound; finer grained MicroDyne requires colder temperatures and higher milling speeds, making it significantly more expensive. PolyDyne is half the cost of nonrecycled synthetic rubber, a third of the price of natural rubber, and nearly half the cost of polypropylene, a polymer commonly used in plastic moldings.

This is an area that Lehigh’s investors are particularly interested in.

“Pick whatever plastic product you want to make and it will have specific technical performance requirements,” says Ben Kortlang a partner at venture capitol firm Kleiner Perkins Caufield & Byers, which recently invested in Lehigh Technologies. “Using a blend of PolyDyne and traditional materials, there will typically be a cost savings and, in many cases, a performance improvement. And many of these markets could be very, very large.”

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Bhushan G. Jagyasi, 30, has developed mKRISHI, a mobile-based agro advisory sys­tem for potato farmers.

Bhushan G. Jagyasi, a scientist with the Tata Consultancy Services Innovation Labs in Mumbai, has been engaged in a rich array of research areas in the fields of distributed detection, signal process­ing, wireless sensor networks, and mobile phone-based sensor networks.

He has developed mKRISHI, a mobile-based agro advisory sys­tem piloted for potato farmers in Bichaula village of Aligarh district in Uttar Pradesh. Jagyasi used the read­ing of weather (moisture, tempera­ture) and crop (leaf wetness) sensors and computed the risk of pest attack on potato crop using several models developed by well known agriculture scientists. He observed that the pest attack predicted by available models, though useful, cannot be used to issue pest attack advisory notice to farmers in absence of certain confidence mea­sure. A wrong advisory warning based on mathematical models would lead farmers to use pesticide excessively. It would also go against the efforts of convincing farmers to use minimum pesticide.

Jagyasi observed the farmers’ pesti­cide queries in that region. The dates when the pesticide queries came from farmers to experts matched more or less with the time of pest attack pre­dicted by the models. To come up with a precise pest attack prediction strategy, Jagyasi decided to combine farmer’s observation of the crop with the output of mathematical models. He developed a model wherein farm­ers personal observation could be sought. Based on that and mathemati­cal model output, agriculture experts at remote locations could give advice on the possibility of pest attack and related prevention measures.

“Jagyasi’s innovative approach of combining human observation with mathematical models will go a long way in reducing pesticide usage by potato farmers and hence reduce farmer’s cost of production. This will also help in improving the yield and reduce the damage to environment, soil, and health,” says Arun K. Pande, head of TCS Innovation Labs, Mum­bai.

The mKRISHI platform bridges the gap between farmers and experts by enabling interaction in local lan­guage through a mobile phone. Jag­yasi’s work opens up a new approach of combining computer science and agriculture technologies for the ben­efit of Indian agriculture industry.

Source TR.

A vast series of earth mounds on the eastern coast of South America may be living landscape fossils of a forgotten civilization’s agriculture.

People raised the mounds between 1,000 and 700 years ago in order to create cropland in terrain that is flooded for half the year, and parched for the other half. New insect ecosystems formed on the mounds, further enriching the soils and keeping them fertile for centuries, long after their human stewards had vanished. This lost agricultural system could be a model for modern farmers, according to a new study.

“Today these lands are used for cattle ranching or hunting. People think agriculture must not be possible in these areas,” said ecologist Doyle McKey of the University of Montpellier in France, co-author of a study published April 12 in the Proceedings of the National Academy of Sciences. “The common conception is that these areas are wastelands.”

McKey and a team of archaeologists, paleobiologists and soil scientists describe the earthworks, which run for 360 miles from the Berbice River to Cayenne, the modern-day capital of Guyana.

The study is part of a fast-growing body of research on the pre-Columbian world of the Amazon basin. Historians and anthropologists once thought it inhabited only by small bands of primitive hunters and gatherers, with interior jungles and coastal floodplains unable to support large-scale agriculture and complex societies. That picture no longer seems accurate.

Scientists have shown that now-vanished people transformed the Amazon, using biochar to nourish jungle soils, and moving floodplain soils to create irrigation channels and planting beds. McKey’s findings expand the range of known coastal agriculture and take an in-depth look at the beneficial ecological changes it created.

“Human engineering, if we do it cleverly, can work together with natural ecosystem engineering,” said McKey.

In addition to 100-foot-long, water-diverting berms, they identified expanses of mounds covering hundreds of acres. From the air, the mounds were too symmetrical to be natural. On the ground, soil samples returned fossilized evidence of maize, squash and manioc.

The mounds appear to have been constructed from layers of surrounding topsoil, which was shoveled out and layered like cakes. That formed the basis of the mounds, which put crops above the flood line but that was only one part of the agricultural trick.

Species of ants and termites settled in the mounds, where their colonies wouldn’t flood. Their burrowing aerated the soil, and plant matter foraged from surrounding areas enriched it further. As a result, the mounds acted like sponges for rainfall, and outsourced insect labor made them rich in key fertilizer nutrients of nitrogen, potassium and calcium. The root systems of perennial plants kept the mound structures intact, and likely did so when mounds were rotated out of production.

McKey is reluctant to speculate on how many people were supported by mound agriculture. A conservative guess based on crop yields from modern raised-bed farming experiments put the figure at one person for every two acres of farmland. That’s a very rough estimate, but enough to suggest that the farmers were not just small, family-based tribes.

More important than exact numbers is the evidence of agricultural success in a region that’s not considered suitable for modern agriculture. McKey thinks today’s farmers could learn from ancient tricks, and supplement them with modern tools.

As for the original inhabitants, little is known. They belonged to so-called Arauquinoid cultures, which emerged 1,500 years ago and vanished shortly before the arrival of Europeans. Whether they left descendants is unknown. They’re known only from a single wooden shove, some ceramic fragments and their farms.

“When people modified these ecosystems long ago, they changed the way the ecosystems work. We can use that knowledge,” said McKey.

Images: 1) Farm mounds from above and the ground./PNAS. 2) A map of northeastern Amazon coastal earthworks./PNAS. 3) Satellite and interpretive imagery of a site near Kourou, Frency Guiana/PNAS.

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Saudi Arabia’s newest purification plant will use state-of-the-art solar technology.

Saudi Arabia meets much of its drinking water needs by removing salt and other minerals from seawater. Now the country plans to use one of its most abundant resources to counter its fresh-water shortage: sunshine. Saudi Arabia’s national research agency, King Abdulaziz City for Science and Technology (KACST), is building what will be the world’s largest solar-powered desalination plant in the city of Al-Khafji.

The plant will use a new kind of concentrated solar photovoltaic (PV) technology and new water-filtration technology, which KACST developed with IBM. When completed at the end of 2012, the plant will produce 30,000 cubic meters of desalinated water per day to meet the needs of 100,000 people.

KACST’s main goal is to reduce the cost of desalinating water. Half of the operating cost of a desalination plant currently comes from energy use, and most current plants run on fossil fuels. Depending on the price of fuel, producing a cubic meter now takes between 40 and 90 cents.

Reducing cost isn’t the only reason that people have dreamed of coupling renewable energy with desalination for decades, says Lisa Henthorne, a director at the International Desalination Association. “Anything we can do to lower this cost over time or reduce the greenhouse gas emissions associated with that power is a good thing,” Henthorne says. “This is truly a demonstration in order to work out the bugs, to see if the technologies can work well together.”

While the new concentrated PV technology might generate affordable electricity, solar power still costs more than fossil fuels in many parts of the world. But even with those high costs, using it to power desalination makes sense, Henthorne says. “You’re not doing it because it’s the cheaper thing to do right now, but it would be the cheapest thing down the road.”

Desalination plants typically use distillation. Most upcoming plants, including the one in Al-Khafji, will use a process called reverse osmosis, which forces seawater through a polymer membrane using pressure to filter out salt. Both these methods are energy-intensive. Saudi Arabia, the top desalinated water producer in the world, uses 1.5 million barrels of oil per day at its plants, according to Arab News.

The new plant’s concentrated PV and reverse-osmosis systems will use advanced materials developed by IBM for making computer chips.

In a concentrated PV system, lenses or mirrors focus sunlight on ultra-efficient solar cells that convert the light into electricity. The idea is to cut costs by using fewer semiconductor solar cell materials. But multiplying the sun’s power by hundreds of times creates a lot of heat. “If you don’t cool [the device], you end up overheating the circuits and killing them,” says Sharon Nunes, vice president of IBM Big Green Innovations. IBM’s solution is to use a highly conducting liquid metal–an indium gallium alloy–on the underside of silicon computer chips to ferry heat away. Using this liquid metal, the researchers have been able to concentrate 2,300 times the sun’s power onto a one-square-centimeter solar device. That is three times higher than what’s possible with current concentrator systems, says Nunes.

For desalination, IBM has worked with researchers at the University of Texas at Austin to develop a robust membrane that makes reverse osmosis more energy-efficient. Desalination is done today with polyamide membranes that get clogged with oil and organisms in seawater. The chlorine used to pretreat seawater also breaks down the membranes over time.

The new polymer membrane contains hexafluoro alcohols, a material IBM uses to pattern copper circuits on computer chips. At high pH, the fluorine groups become charged and protect the membrane from chlorine and clogging. As a result, water flows through it 25 to 50 percent faster than through currently used reverse-osmosis membranes, according to IBM.

The new membrane removes 99.5 percent of the salt in seawater. This is comparable with conventional polyamide membranes, says Menachem Elimelech, chair of chemical engineering at Yale University. “You need to achieve this high rejection, otherwise you can’t get good water quality by one pass, you have to desalinate again.”

The Al-Khafji desalination plant is the first of three steps in a solar-energy program launched by KACST to reduce desalination costs. The second step will be a 300,000-cubic-meter facility, and the third phase will involve several more solar-power desalination plants at various locations.

Source TR.

Sriram Kannan, has created a created a system for accessing medical images on mobile phones.

Globally, every five seconds someone goes blind from diabetic retinopathy, infant retinopathy of prematurity, eye can­cer and other diseases. The majority of these are preventable, if screened regu­larly. However, many of the afflicted are in rural areas where there is a shortage of ophthalmologists. Take for example, Retinopathy of Prematurity (ROP). It is the leading cause of preventable infant blindness worldwide. Ravindra R. Battu, medical director, Narayana Nethralaya, Bangalore, says, “The cause is attributable to the fact that a prema­ture baby has an immature set of reti­nal vasculature. With exposure to the outside world with a higher percentage of oxygen, together with other risk fac­tors which include several neonatal ill­nesses especially sepsis and anemia, the immature vessels begin to get ‘strained’ and instead of normally progressing to supply the rest of the retina, ‘arrest’ in their development and cause a ridge of extra-retinal tissue.”

Most of this blindness can be pre­vented if diagnosed properly and treated early. Teleophthalmology technology that brings patient data and high quality images to the ophthalmologist can help alleviate this problem. But the challenge is to efficiently capture, pre-screen, and transfer information to specialists.

Sriram Kannan, a wireless expert, undertook the challenge of enabling the ophthalmologists with instant access to the high quality images of the scan and developed a system through which access to images was made available on a mobile phone, anytime. iPhone was the platform of his choice. The system was designed to be standards compliant (DICOM and HL7 standards related to medical images and information) and tweaked to use the network bandwidth optimally.

This is the first iPhone client based teleophthalmology application in the world. He worked very closely with oph­thalmologists at Narayana Nethralaya in understanding the clinical require­ments for viewing, diagnosing, and reporting on retinal images.

“Sriram’s work involved building a prototype using Apple’s Software Development Kit which is available on the MAC platform and interfacing it to patient images and data from a hosted server using secure connectivity and image compression algorithms. Field trials were then conducted in live clini­cal sessions between hospital in Ban­galore and patient sites in Kolar and in Kolkata. It took roughly six months of development for the first production release. He is now working on develop­ing this application into other specialist areas like telecardiology and teleden­tistry,” adds Sham Banerji, chairman and CEO, i2i TeleSolutions.

The overall solution uses a math­ematical compression algorithm that achieves high compression ratios for medical images. This results in storage cost savings and faster transmission of images across the networks. The iPhone client application uses image stream­ing protocol optimized for wireless networks. It exploits the rich features of iPhone for an enhanced user experi­ence. The image viewing module is opti­mized based on health care specialty.

This solution is now undergoing clinical trials with experts from India, Canada, and U.S. and has the potential of fundamentally changing the way eye care, cardialogy, and dentistry is deliv­ered in remote regions of the world.

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Predictable sights trigger less brain activity than unfamiliar stimuli, bolstering the view that the brain is not merely reactive, but generates predictions based on the recent past. “The brain expects to see things and really just wants to confirm it now and again,” says Lars Muckli at the University of Glasgow, UK.

He and Arjen Alink at the Max Planck Institute for Brain Research in Frankfurt, Germany, asked 12 volunteers to focus on a cross on a screen, above and below which bars flashed on and off to create the illusion of movement. To test a predictable stimulus, a third bar would appear in a position timed to fit in with the illusion of smooth movement. For the unpredictable stimulus it would appear out of sync. fMRI scans showed that the unpredictable stimulus increased the activity in parts of the brain which deal with the earliest stages of visual processing (Journal of Neuroscience, vol 30, p 2960).

The finding supports the “Bayesian brain” theory, which sees the brain as making predictions about the world which it updates when new information comes in.

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The first continuous monitoring system for glaucoma hits the European market.

Glaucoma is the second most common cause of blindness, and without constant vigilance it can prove a very difficult disease to manage. But a Swiss biotech company has developed a monitoring system that allows physicians to keep track of their patients’ symptoms over 24 hours. Sensimed’s “Triggerfish” system consists of a contact lens with embedded sensors that can pick up subtle physical changes in a patient’s eye, and then wirelessly transmit that data to a receiver worn around his neck.

Despite decades of study, researchers still only poorly understand the causes of glaucoma, a group of diseases in which deterioration of the optic nerve can eventually lead to blindness. But controlling one symptom in particular–high intraocular pressure, which is caused by too much liquid inside the eye–appears to help prevent disease progression.

“Nowadays, glaucoma specialists live in the dark,” says Kaweh Mansouri, an ophthalmologist who has been using the Sensimed system in his clinic at the University Hospital, Geneva. “We only get a few chances to see the patient and measure intraocular pressure, and we know this is a major drawback of how we diagnose and treat glaucoma.”

Current methods for glaucoma diagnosis and monitoring are usually limited to single snapshots in time, taken at a visit to the eye doctor during daytime, when pressure tends to be at its lowest. But glaucoma specialists believe that one of the main contributors to disease progression is frequent changes in pressure over the course of a day, or high peaks during the night–something that, in the most serious cases, requires frequent measurement during an overnight hospitalization. The Sensimed device, the first of its kind on the market, provides constant readings for a fraction of the price of a hospital stay. The company received safety approval for Triggerfish in Europe last year, and is hoping for U.S. Food and Drug Administration approval by late 2011.

The Triggerfish lens is made of the same silicon hydrogel as many of the soft contact lenses currently on the market, but embedded within it is a microprocessor and a strain gauge that encircles its outer edge. When fluid accumulates in the eye, the diameter of the cornea changes, and that change is picked up by the strain gauge. Data is processed and then transmitted via radio frequency to a receiver.

In more than one-third of the 50 patients Mansouri has tested, the results led to a direct, immediate change in treatment, he says. If a person’s intraocular pressure peaked at odd hours of the night, for example, he could now detect it and change medication doses to account for that. If prescription drugs didn’t seem to be helping at all, he could change course and try surgery instead. “For the first time, we were able to look into the darkness of glaucoma, and we saw things happening during the night that were surprising,” he says.

Ultimately, Sensimed believes it may be possible to use Triggerfish to detect glaucoma at earlier stages in people with a family history of the disease or other risk factors. If a high-risk patient has a relatively normal daytime pressure, says company president and CEO Jean-MarcWismer, he might benefit from a preventative 24-hour monitoring session every once in a while. “We would like to be able to diagnose glaucoma earlier, before it actually causes damage that affects vision.”

This may be a bit premature, says Andrew Iwach, the executive director of the Glaucoma Center of San Francisco. “Some patients have high intraocular pressure, but their optic nerve tends to do fine. Others have lower pressure, but still have a major impact on their optic nerve,” says Iwach, who’s also spokesperson for the American Academy of Ophthalmology. The problem, experts say, is that increased intraocular pressure is the only symptom of glaucoma that is treatable and can slow or stop disease progression.

However, both Iwach and Stanford ophthalmology professor Kuldev Singh believe that continuous monitoring of intraocular pressure is something the field desperately needs, and note that there are multiple groups working toward such a goal. But while the new device will likely have a major benefit in understanding individual patients’ treatments, Singh says, it also provides an important opportunity to better understand the disease. “The idea of a continuous measurement device for eye pressure is a very, very good one,” he says. “I think the most important use for it is to better study the relationship between eye pressure and glaucoma progression.”

“From a scientific standpoint, this type of technology will be groundbreaking in letting us understand the relationship between eye pressure and glaucoma, and how treatments work over a 24-hour period,” says Singh, who is also chair of the Glaucoma Research Foundation‘s board of directors.

To date, the device has only been used clinically in about 80 patients–the holdup, says Mansouri, is price: It’s not yet reimbursed by the Swiss health care system. Prices should drop, however, as reimbursement increases and production scales up.

Farmers in rural India now have something to smile about, courtesy Rikin Gandhi. An aeronautical and astronautical engineer from Massachusetts Institute of Technology, U.S., Gandhi is the founder of Digital Green which disseminates targeted agricultural information to farmers at a reasonable cost using participatory video and mediated instruction.

Digital Green uses locally produced videos of sustainable agriculture techniques as a means to amplify the impact of agriculture extension workers who help farmers become more productive. Incubated at Microsoft Research India, Digital Green is an independent non-profit organization (NGO) which partners with other organizations, universities,
governments, and NGOs across South Asia and Africa.

“Many farmers in developing countries, such as India, often lack knowledge that could immediately improve their livelihoods. To educate such a vastly scattered adult population, two key areas need to be developed: locally relevant content production and distribution,” says Gandhi adding, “One of the clearest things I observed was the degree to which farmers sought videos featuring people similar to themselves. Like viewers of reality television, farmers made snap judgments of a person’s occupation, education, and station, apparently based on language, clothing, and mannerism
cues. The effect of a local mediator during screening was also significant. Because mediators make the content active, by reiterating concepts between clips, questioning to gauge interest, and announcing follow-up screenings, audiences
remained engaged.”

Rikin spent six months in rural Karnataka to discover how best to use locally produced videos to help farmers understand
and adopt better farming practices. Over the next two years he established scientific evidence that the technique works.

“Rikin accomplished a great deal of research during his time in the villages of Karnataka. He spent several months trying
every conceivable way to use a video camera, a DVD player, and a TV to see what sorts of content and what sorts of screenings local farmers would respond to. He held ad hoc screenings in the middle of village roads, and he video recorded agriculture experts as well as farmers. When he felt he had something that was actually helping farmers, he came back to get advice on how to evaluate the system,” says Kentaro Toyama, former assistant director of Microsoft Research India.

Digital Green uses locally produced videos of sustainable agriculture techniques as a means to amplify the impact of agriculture extension workers who help farmers become more productive.

Using cost-realistic technologies such as TVs, DVD players, and camcorders, Digital Green cultivates a hub-and-spoke-based ecosystem of educational, entrepreneurial, and entertaining content.

“Rikin is a rare individual who has both the smarts, the discipline, and the drive to push constantly to achieve his goals. He is not only a worker but also an excellent communicator. He had the rare ability and willingness to work at the remotest village and also analyze the data that he was gathering. I think it is this combination that is unique,” reflects Rajesh Veeraraghavan, a PhD student at the School of Information at UC Berkeley.

Rikin’s Digital Green has been 10 times as effective, per dollar spent, in converting farmers to better farming practices than classical approaches to agriculture extension workers. The Gates Foundation funded Rikin with a $800,000 grant to scale the idea through Digital Green.

“We anticipate that with support from the Gates Foundation, Rikin and his team at Digital Green will have impact over 1,000 villages, each consisting of 1,000-2,000 people. Indeed, they are already on the way there,” says Toyama.

Source TR.

Remote Power For the Fields

A bachelor in electronics and communication from Visveswaraiah Technological University, Karnataka, Prajwal Kumar specializes in robotics and automation. He has recently developed a remote controlled system for power tiller. Farmers have to walk along with the power tiller to control its direction. However, now the electronics remote control device can enable the farmers to operate his power tiller without even getting into the field. It ain’t just this. His other inventions include tree-climbing and harvesting robots, paddy field weeding machine, industrial inspections robots, and an unmanned ground vehicle (UGV).

“Prajwal is very creative, intelligent, and a hardworking person. His innovative remote controlled system for power tiller will solve the major problem of farmers who used to operate the power tiller in hot sun, heavy rains, and had to go walking along with the machine controlling its direction for 10 hours a day. Prajwal has found his potential costumer and has supplied 50 pilot pieces as a demo unit for the Bangalore-based VST Tiller Tractors Limited. This technology is one of its kind in the whole world which will bring a revolution in the field of farming,” says Nanajunda, a financial advisor to Kumar and a chartered accountant in Bangalore.

Kumar cofounded Mangalore Robotronics Technologies in Surathkal, Karnataka, in 2006. “His development is a next generation technology and a revolutionary concept in power farming in the agricultural sector with potential for commercialization across the globe,” says P. Suresh Bhat, director, NITK-Science and Technology Entrepreneurs Park (NITK-STEP), National Institute of Technology, Karnataka.

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The rapid results are possible because of a novel microfluidics technology developed by startup Claros Diagnostics, which hopes to make quick PSA monitoring in the doctor’s office a reality. If approved by the U.S. Food and Drug Administration, the device will be one of the first examples of long-awaited microfluidics-based diagnostics tests that can be performed in the hospital or doctor’s office. While microfluidics–which allows for the manipulation of fluids on a chip at microscopic scales–has been around for a decade, the complexity and expense has kept it largely limited to research applications.

Claros’s technology, which consists of a small blood-collector device, a disposable cartridge, and a toaster-sized reader, could, in theory at least, be adapted to detect any number of different proteins. But the company has initially chosen to focus on PSA, which is routinely monitored. With current testing, blood samples are typically sent to a centralized lab for PSA analysis. Results are returned in a day or two. Claros’s test, now in clinical trials, would allow PSA readings to be determined during the patient’s visit. While there is debate over how useful PSA testing is in diagnosing cancer, it is a well-accepted tool for monitoring those who have it. Within a month after prostate surgery, a man’s PSA levels drops–a subsequent increase suggests that PSA producing cancer cells have returned.

“Having a quick PSA test that is accurate would certainly be helpful to most urologists–simple and inexpensive being the two key words,” says Jerome Richie, chief of urology at Brigham and Women’s hospital in Boston. But he says that such a test must be able to accurately analyze the low levels of PSA that are present after prostate surgery.

Key to Claros’s device is its ability to perform the test on a small drop of blood. The surface of the cartridge is covered in narrow channels, which serve as both storage for the chemicals needed for the assay and as tiny test tubes in which to carry out the reaction. Each reagent is lined up sequentially in one long channel and separated by small air bubbles. Once the cartridge is inserted into the reader, a vacuum pulls the blood through one channel and delivers the appropriate sequence of reagents. This approach avoids the pumps used to move chemicals in other microfluidics chips, enabling a simple and robust design with no moving parts. The reader itself is simple, using an LED and photodiode to detect the buildup of silver–the output of the reaction–on the cartridge. The more silver, the less light passes through the chip and the higher the PSA level.

Scientists at Claros developed proprietary injection molding technologies that permit the hard-plastic cartridges to be made very quickly, in about 15 seconds, and for about 10 cents apiece. “Injection molding is used to make lots of consumer products, like pens, but we can manufacture them to micron-sized resolution,” says Samuel Sia, one of Claros’s cofounders and a bioengineer at Columbia University. “They cost just a few cents, and we can make hundreds of thousands per year–not many people can do that.”

Claros is currently running clinical trials to compare its device to standard PSA testing methods in order to garner regulatory approval. If approved, it could make a prostate-cancer patient’s visit to the doctor’s office much more productive. According to Stephen Zappala, a urologist at the Lahey Clinic in Andover, MA, who is working with Claros on the clinical trials, “the Claros technology will dramatically increase the efficiency of the urologist’s practice and alleviate patient anxiety associated with waiting for a laboratory result.”

Vincent Linder, a cofounder and chief technology officer, says Claros expect results from the trial in the next few months. The company hopes to launch the device in Europe later this year and in the United States in 2011. Similar technology could be used to create screening panels for women’s health or cardiac health, though Linder declined to discuss specific plans. He also declined to give an estimate of the system’s price.

In addition to the PSA monitoring device, which will be marketed in the U.S and Europe, Sia is developing a second version of the system to screen for infectious diseases in poor countries. While it uses the same core technology, this version has a battery-powered reader about the size of an iPhone and is designed to detect HIV, syphilis, and hepatitis. The device is currently being tested in health-care centers in Rwanda that treat pregnant women. “If you catch the diseases in mothers, you can prevent transmission to newborn, increasing clinical impact,” says Sia. After a series of successful field trials, Sia is now trying to find funding to move the device through the regulatory process in Africa.

Source TR.