Interesting finds

November 3, 2009

Get a Bordeaux room

Filed under: Architecture, Art & Design, Building — thewere42 @ 7:41 pm

0spircell01Posted by hipstomp

Have you ever been sitting in your panic room during a home invasion and thought to yourself: Why the heck don’t I have my collection of prized wines down here? Most of us know that helplessly monitoring armed intruders in ski masks while they pillage your parlor goes down easier with a spot of 19th century Madeira. “Oh, look at that,” you’d say, staring at the grainy black-and-white image while absently swirling your glass, “the little bastards are taking the Rembrandt.”

There’s this company called Spiral Cellars that doesn’t really make panic rooms, but they do make these cool turnkey wine cellars. They do everything: These guys show up in a van, jackhammer through your foundation, build this crazy spiral staircase that’s got the wine bottles stored in a spiral around the periphery, and even take care of the paperwork with your local government.

Okay so I realize this is out of the reach of most of us–I think if I was that rich, I wouldn’t ever even need to look at the internet–but relatability be damned, I can’t help but find this company and their product fascinating, what with their wide variety of motorized trap doors and the like. And while home invasion isn’t cool, panic rooms and secret wine cellars are cool. Very, very cool.

http://www.core77.com/blog/object_culture/screw_panic_rooms_get_a_bordeaux_room_15100.asp

0spircell03

Volcanic Rift in Ethiopian Desert Confirmed As Beginning of New Sea

Filed under: Beautiful World, Earth, Science, Water — thewere42 @ 7:41 pm

20091103-dabbahu-fissurephoto: © thebigmonkey via flickr.

by Matthew McDermott, New York, NY

A 35-mile long volcanic rift in the Ethiopian desert that opened up back in 2005 has been confirmed as likely being the beginning of a new sea. That’s the word from an international team of scientists, whose work has been published in the journal Geophysical Research Letters:

The rift began when Mount Dabbahu erupted, for the first time in recorded history, and in a matter of just three weeks spread to up to 25′ wide along a fault line in the Afar desert. Heading towards the Red Sea, it could eventually split off Eritrea, Djibouti and part of Ethiopia from the rest of the continent.

Rather than opening up in a series of small earthquakes, magma was pushed up in the middle of the rift and the whole thing began “unzipping” in either direction.

Report co-author Cindy Ebinger of the University of Rochester said, “We know that seafloor ridges are created by similar intrusion of magma into a rift, but we never knew that a huge length of the ridge could break open at once like this.”

In all, the processes at work here are “nearly identical to those at the bottom of the world’s oceans” the report said.

http://www.treehugger.com/files/2009/11/rift-ethiopian-desert-confirmed-beginning-new-sea.php

(Because it looks cool) – Jay Leno Camaro

Filed under: Art & Design, Just Interesting, Vehicles — thewere42 @ 7:41 pm

01-leno-camaro-semaSEMA 2009: Jay Leno Camaro a pre-emptive strike against EcoBoost ‘Stang

by Frank Filipponio

http://www.autoblog.com/2009/11/03/sema-2009-jay-leno-camaro-a-pre-emptive-strike-against-ecoboost/

What do you get the guy who has everything? For SEMA 2009, GM decided to go with the less-is-more approach and built Jay Leno his own special Camaro… with less. Less cylinders at any rate, as this V6 special more than makes up for its lack of firing pots by adding a pair of turbochargers.

The 3.6-liter direct-injected V6 is otherwise similar to the unit that resides in run-of-the-mill Camaro LS and LT models, but with the dual huffers helping it, it produces the same 425 horsepower as its V8-propelled SS brother. And in a playful EcoBoasting slap, Chevy points out that they get the extra performance with virtually no penalty in fuel economy. Take that, rumored EcoBoost Mustang!

Besides the power upgrades, the Leno Camaro also gets a beefed up clutch for its six-speed transmission, an upgraded radiator, Brembo brakes, a Pedders coil-over kit, and a bodykit that includes a new rear diffuser as well as a revised front fascia and hood with additional venting for brakes and engine. It’s one of a handful of Camaros in the GM booth, but it’s the only one sticking its chin out, egging on the Ford boys. Press release after the jump and full gallery below.

Follow the link for a  lot more pictures - http://www.autoblog.com/2009/11/03/sema-2009-jay-leno-camaro-a-pre-emptive-strike-against-ecoboost/

Speed Limit To The Pace Of Evolution, Biologists Say

Filed under: Biology — thewere42 @ 7:41 pm

091102171726E. coli growing in a petri dish. (Credit: iStockphoto/Linde Stewart)

Researchers at the University of Pennsylvania have developed a theoretical model that informs the understanding of evolution and determines how quickly an organism will evolve using a catalogue of “evolutionary speed limits.” The model provides quantitative predictions for the speed of evolution on various “fitness landscapes,” the dynamic and varied conditions under which bacteria, viruses and even humans adapt.

A major conclusion of the work is that for some organisms, possibly including humans, continued evolution will not translate into ever-increasing fitness. Moreover, a population may accrue mutations at a constant rate — a pattern long considered the hallmark of “neutral” or non-Darwinian evolution — even when the mutations experience Darwinian selection.

While much is known about the qualitative aspects of evolutionary theory — that organisms mutate and these mutations are selected by the environment and are gradually absorbed by the entire population, very little is known about how, or how quickly, this is accomplished. Information on evolution between consecutive generations is hard to come by, and the lack of understanding has real-world implications. Public-health officials would have an easier time preparing targeted vaccinations, or combating drug resistance, if they understood the evolutionary speed limits on viruses and bacteria such as influenza and M. tuberculosis.

Penn researchers presented a theory of how the fitness of a population will increase over time, for a total of 14 types of underlying landscapes or “speed limits” that describe the consequences of available genetic mutations. These categories determine the speed and pattern of evolution, predicting how a population’s overall fitness, and the number of accumulated beneficial mutations, are expected to increase over time.

Researchers compared the theory to the data from a two-decades study of E. coli to investigate how the bacterium evolves. Organisms of that simplicity and size reproduce more rapidly than larger species, providing 40,000 generations of data to study.

“We asked, quantitatively, how a population’s fitness will increase over time as beneficial mutations accrue,” said Joshua B. Plotkin, principal investigator and an assistant professor in the Department of Biology in Penn’s School of Arts and Sciences. His research focuses on evolution at the molecular scale.

“This was an attempt to provide a theoretical framework for studying rates of molecular evolution,” said first-author Sergey Kryazhimskiy, also of the Department of Biology. “We applied this theory to infer the underlying fitness landscape of bacteria, using data from a long-term bacterial experiment.”.

In some theoretically conceivable landscapes, fitness levels are expected to increase exponentially forever because of an inexhaustible supply of beneficial mutations. But in more realistic landscapes the rate of adaptive substitutions (mutations that improve an organism’s fitness) eventually lose steam, resulting in sub-linear fitness growth. In some of these landscapes, the fitness eventually levels out and the organism ceases to adapt, even though mutations may continue to accrue.

E. coli, for example, has been observed to increase its rate of cellular division by roughly 40 percent during the course of 40,000 generations. Initially, the bacterial fitness increased rapidly, but eventually the fitness leveled out. These data have allowed the research team to infer that early mutations, while conferring large beneficial effects, also diminish the beneficial effects of subsequent mutations.

According to the study, a population’s fitness and substitution trajectories — t he mutations acquired to achieve higher fitness — depend not on the full distribution of fitness effects of available mutations but rather on the expected fixation probability and the expected fitness increment of mutations. This mathematical observation greatly simplifies the possible trajectories of evolution into 14 distinct categories.

Researchers demonstrated that linear substitution trajectories that signify a constant rate of accruing mutations, long considered the hallmark of neutral evolution, can arise even when mutations are strongly beneficial. The results provide a basis for understanding the dynamics of adaptation and for inferring properties of an organism’s fitness landscape from long-term experimental data. Applying these methods to data from bacterial experiments allowed the researchers to characterize the evolutionary relationships among beneficial mutations in the E. coli genome.

The study, appearing in the current issue of the journal Proceedings of the National Academy of Sciences, was performed by Plotkin and Kryazhimskiy along with Gašper Tkacik of the Department of Physics and Astronomy at Penn.

The study was funded by the Burroughs Wellcome Fund, the David and Lucille Packard Foundation, the James S. McDonnell Foundation, the Alfred P. Sloan Foundation, a Defense Advanced Research Projects Agency grant and the National Science Foundation.


Adapted from materials provided by University of Pennsylvania

 

http://www.sciencedaily.com/releases/2009/11/091102171726.htm

Warren Buffett Buys A RAILROAD? Berkshire Hathaway Acquires Burlington Northern Railroad

Filed under: Trains — thewere42 @ 7:40 pm

s-BERKSHIRE-BURLINGTON-largeSAMANTHA BOMKAMP

NEW YORK — Warren Buffett’s Berkshire Hathaway Inc. on Tuesday agreed to buy Burlington Northern Santa Fe Corp., making a $34 billion bet on the future of the U.S. economy.

Burlington Northern, the nation’s second-largest railroad, is the biggest hauler of food products like corn and coal for electricity, making it an indicator of the country’s economic health. The railroad also ships a large amount of goods from Western ports including everyday items such as refrigerators, clothing and TVs.

Analysts say Buffett is planting both feet in an industry that is poised to grow as the economy gets back on solid ground. If approved, it would be the biggest acquisition ever for Berkshire Hathaway Inc.

Berkshire Hathaway already owns about 22 percent of Burlington Northern, and said it will pay $100 a share in cash and stock for the rest of the company, a 31.5 percent premium on Burlington Northern’s Monday closing price. Shareholders have the option to convert their stock for a cash payment of $100 per share or receive Berkshire Class A or Class B common stock. Up to 60 percent of the deal is cash and 40 percent is in stock.

“Berkshire’s $34 billion investment in BNSF is a huge bet on that company, CEO Matt Rose and his team, and the railroad industry,” Buffett said in a statement.

“Most important of all, however, it’s an all-in wager on the economic future of the United States. I love these bets,” he said.

The majority of the stock in the deal will be Berkshire’s “A” shares, but Berkshire’s board also approved a 50-for-1 split of its Class B common stock for holders of smaller amounts of Burlington shares who opt for a share exchange rather than cash. Berkshire’s Class B shares closed Monday at $3,265. With the split, each share will be worth $65.30. Burlington shares shot up $21.33, or 28 percent to $97.40 in morning trading. Shares of other major rails, including Burlington’s larger rival Union Pacific Corp., rose as well.

Berkshire also owns stock in two other major U.S. railroads – 9.56 million shares of Union Pacific Corp. and 1.93 million shares of Norfolk Southern Corp., as of June 30.

The deal for Burlington Northern has been approved by the boards of both companies, but still needs two-thirds approval of Burlington’s shareholders and antitrust clearance. The railroad expects to clear those hurdles in the first three months of next year.

Last week the railroad reported third-quarter profit dropped 30 percent to $488 million, or $1.42 per share, as consumers continued to hold back on buying retail goods and industrial production struggled.

Burlington was one of the least optimistic among major railroads about the pace of economic recovery. CEO Matt Rose said consumers are going to be the driver of any improvement in the economy, but no one is buying yet.

Analysts say Buffett is looking for an investment that will reap rewards for many years into the future, and isn’t so concerned about immediate gains.

“(Buffett is) buying at the trough – things aren’t going to get much worse. He’s getting in at a good time,” said Art Hatfield, an analyst with investment firm Morgan Keegan.

Hatfield said he believes Buffett went for Burlington Northern in part because of its good management team, an important aspect in any of the billionaire’s deals.

Hatfield also said that Burlington Northern has been more progressive than its peers in developing new technology, allowing to be more profitable. Major railroads have been able to slash costs during the recession by cutting jobs, parking railcars and making strides to improve train speeds and other metrics that improved efficiency.

___

AP Business Writers Josh Funk in Omaha and Deborah Jian Lee in New York contributed to this report.

http://www.huffingtonpost.com/2009/11/03/buffetts-berkshire-burlin_n_343418.html

Crisis Compels Economists To Reach for New Paradigm

Filed under: Financial — thewere42 @ 7:40 pm

P1-AS320_PARADI_G_20091102170032Jesse Neider for the Wall Street Journal – Yale economist John Geanakoplos has seen his previously obscure theory about collateral’s role in the credit bubble gain currency after it burst.

By MARK WHITEHOUSE

The pain of the financial crisis has economists striving to understand precisely why it happened and how to prevent a repeat. For that task, John Geanakoplos of Yale University takes inspiration from Shakespeare’s “Merchant of Venice.”

The play’s focus is collateral, with the money lender Shylock demanding a particularly onerous form of recompense if his loan wasn’t repaid: a pound of flesh. Mr. Geanakoplos, too, finds danger lurking in the assets that back loans. For him, the risk is that investors who can borrow too freely against those assets drive their prices far too high, setting up a bust that reverberates through the economy.

For years, his effort to understand this process didn’t draw much interest. Now it does — yet another aftereffect of the brutal deflating of the credit bubble. The crisis exposed the inadequacy of economists’ traditional tool kit, forcing them to revisit questions many had long thought answered, such as how to tame disruptive boom-and-bust cycles.

Mr. Geanakoplos is among a small band of academics offering new thinking about those cycles. A varied group ranging from finance specialists to abstract theorists, they are moving to economic center stage after years on the margins. The goal: Fix the models that encapsulate economists’ understanding of the world and serve as policy-making tools at the world’s biggest central banks. It is a task that could require a thorough overhaul of the way those models work.

“We could be looking at a paradigm shift,” says Frederic Mishkin, a former Federal Reserve governor now at Columbia University.

That shift could change the way central bankers do their job, possibly leading them to wade more deeply into markets. They could, for example, place greater emphasis on the amount of borrowing in the economy, rather than just the interest rates at which borrowing is done. In boom times, that could lead them to restrict how much money various players, ranging from hedge funds to home buyers, can borrow.

Mr. Geanakoplos is emblematic of the new thinking but not necessarily the one whose ideas will prevail. It’s too early in the process to know. But he was among a group of academics whom Federal Reserve Chairman Ben Bernanke invited in to discuss the crisis at its peak in October 2008.

The past century saw two revolutions in the way economists view the world. Both required painful crises to set them in motion, but both arguably improved government’s ability to manage the economy.

The first came after the Depression, when economists built some of the first mathematical models that policy makers could use to try to manage the economy. The second came after the inflationary 1970s, when economists created new models that took into account how people’s expectations, such as about prices or income, can influence the economy over time.

During the second revolution, the U.S. economy entered a period of stability and low inflation that lasted from the 1980s through most of the 2000s, leading many economists to believe they had triumphed over business cycles. As Robert Lucas of the University of Chicago, one of the intellectual fathers of the models, put it in 2003: The “central problem of depression-prevention has been solved…for many decades.”

The result was a new orthodoxy, known as “rational expectations,” that still dominates, underpinning everything from the way pension funds invest to how financial analysts put values on securities. Among its main branches is the idea that markets are “efficient,” meaning that even an uninformed investor can get a fair shake, because the price of any security tends to reflect all available information relevant to its value.

Mr. Geanakoplos didn’t buy it. A former U.S. junior chess champion schooled in math and economic theory at Harvard, he had spent much of his career looking for holes in the dominant theories. His skepticism was seasoned with real-world experience, as head of fixed-income research at the now-defunct brokerage house Kidder, Peabody & Co. and after 1995 as a partner at a hedge fund that specializes in mortgage-backed securities, Ellington Capital Management.

On Wall Street, Mr. Geanakoplos, now 54 years old, noticed what he saw as a serious market limitation: There weren’t enough houses and other forms of collateral to back all of the large amounts of debt securities that bankers might want to create. So when investors demanded more “asset-backed” securities, bankers had to find ways to “stretch” the available supply of collateral.

One way was to make collateral do double-duty. For instance, mortgage loans the banks made became collateral themselves for complex debt securities, known as collateralized mortgage obligations.

Another way of stretching collateral was to lend more against it. For example, if a bank lowered the down payment on a $100,000 house to 5% from 20%, it could have $95,000 in loans against the house instead of $80,000. In a similar way, banks could lower the down payments, or “margins,” they required of investors who use borrowed money to buy bonds and other securities.

A rereading around 1997 of “The Merchant of Venice,” with its talk of a pound of flesh, helped focus Mr. Geanakoplos’s thinking about the importance of collateral. “I thought it was a sign from the gods that I was onto something,” he says.

Another sign came on a Friday morning in October 1998, following the downfall of the hedge fund Long-Term Capital Management. A lender to the fund where Mr. Geanakoplos was a partner abruptly demanded more margin on a loan. The event, which nearly toppled the fund as the partners scrambled to raise cash by selling securities, drove home to Mr. Geanakoplos how margins could work two ways — stimulating asset buying as they go lower, but forcing fire sales as they rise.

In a 2000 academic paper, Mr. Geanakoplos offered a theory. He said that when banks set margins very low, lending more against a given amount of collateral, they have a powerful effect on a specific group of investors. These are buyers, whether hedge funds or aspiring homeowners, who for various reasons place a higher value on a given type of collateral. He called them “natural buyers.”

Using large amounts of borrowed money, or leverage, these buyers push up prices to extreme levels. Because those prices are far above what would make sense for investors using less borrowed money, they violate the idea of efficient markets. But if a jolt of bad news makes lenders uncertain about the immediate future, they raise margins, forcing the leveraged optimists to sell. That triggers a downward spiral as falling prices and rising margins reinforce one another. Banks can stifle the economy as they become wary of lending under any circumstances.

“It was evident to me that there was a cycle going on, not just in my little market, but all over the world,” says Mr. Geanakoplos, who is still a partner at Ellington Capital. The “leverage cycle,” he called it.

This idea had big implications for policy makers. For decades, they thought of interest rates as the most important indicator of supply and demand in credit markets, and the only variable they needed to adjust to achieve a desired economic result. Now, Mr. Geanakoplos was saying that something else — lenders’ collateral or margin demands — could be even more important.

[Paradigm]“I would give him a lot of credit,” says Michael Woodford, an economist at Columbia University and a leader in shaping the models currently in use at central banks. “He is someone who was on this issue…very early.”

Other, better-known economists — including Mr. Bernanke, while he was at Princeton — were also doing work highlighting how finance could affect the broader economy. But none of this work had much impact at the time. With the business cycle thought tamed, economists were more interested in applying their techniques in other areas, such as education and crime, as epitomized in the book “Freakonomics.” Traditional macroeconomics, such as practiced by John Maynard Keynes and Milton Friedman, was relegated to second-class status.

By the middle of this decade, what Mr. Geanakoplos called the leverage cycle was playing out on a grand scale. Motivated by a flood of investment from abroad, U.S. bankers created myriad debt securities backed by assets ranging from credit-card receivables to student loans to corporate bonds. To stretch the available collateral even further, they created hundreds of billions of dollars in ethereal investments known as “synthetic collateralized debt obligations,” whose value was tied to that of bonds and asset-backed securities.

From 2000 to mid-2006, lenders lowered average down payments on riskier home loans to less than 4% from about 14%. During this time, the average U.S. home price soared about 90%, and total U.S. credit-market debt rose 68%, to $43.3 trillion.

Central bankers expressed concern about the debt-fueled boom. But their main forecasting models sounded no alarms, because the models looked only at interest rates, not at any indicator of how much banks were willing to lend on assets. The models “were not able to draw up the red flags,” says Tim Besley, a professor at the London School of Economics who served on the Bank of England’s policy-making committee until recently.

In 2007, with mortgage defaults rising, banks pulled back on home lending. The average down payment they required for riskier home loans jumped to more than 10% in mid-2007, by Mr. Geanakoplos’s calculation. House prices headed lower.

After Lehman Brothers Holdings failed in September 2008, lenders jacked up the margin investors had to put up to buy mortgage securities to nearly 70% from less than 10%, contributing to a wave of selling and losses. Some bankers became reluctant to lend at all.

As the financial system teetered, central bankers’ main models offered little insight as to what the impact on the broader economy might be or what they should do to cushion it. It was just good luck, some economists say, that the Fed’s chairman had spent much of his career studying what to do in such a situation. “Bernanke had the right model in his head,” says Larry Christiano of Northwestern University.

Now that the financial crisis has exposed flaws in the models central banks use, economists have launched into a flurry of activity that is likely to reshape the field. As they did in the two revolutions in economic thought of the past century, economists are rediscovering relevant work. Mr. Woodford asked Mr. Geanakoplos to present his ideas at an April conference held by the National Bureau of Economic Research.

Mr. Geanakoplos has yet to develop his theory into a comprehensive model. “His work assumes that the leverage cycle is bad, but gives little guidance [about] to what extent regulators should control it,” says Markus Brunnermeier, an economist at Princeton who specializes in financial bubbles.

The goal for economists now is a model that takes account of what happens in the financial sector, yet is simple enough to apply in policy making. The quest is bringing financial economists — long viewed by some as a curiosity mostly relevant to Wall Street — together with macroeconomists. Some believe a viable solution will emerge within a couple of years; others say it could take decades.

Coming up with the right model could force economists to move away from the ideas of efficient markets and rational expectations on which much of their current work relies. “If that happens, that will be a change of enormous proportions,” says Martin Eichenbaum, a professor of economics at Northwestern.

Mr. Geanakoplos is convinced such a paradigm shift is under way. He hopes it will prove beneficial in protecting people from the excesses of the financial markets. To that end, he believes central bankers should collect and publish data on the amount of leverage in the system, and intervene if it gets out of line.

Right now, that would require the Fed to step in where banks fear to go by lending against risky assets such as mortgage bonds, but it would also mean limiting investors’ ability to use leverage in exuberant times.

“Our policy seems geared largely toward rescuing banks and bankers,” Mr. Geanakoplos says. “If we could manage these cycles better, I think we’d all be better off.”

Economist Profiles

In the wake of the worst financial crisis since the Great Depression, economists are racing to provide policy makers with the tools they need to avert a repeat — a process that some believe could require a revolution in economic thought. In doing so, they are building on the work of colleagues who saw early on the dangers presented by an unstable financial sector. Here are some of the people who did the early work, and who are now using it to build new models of the economy.

http://online.wsj.com/article/SB125720159912223873.html

Walmart eyes urban expansion in US

Filed under: Big Business, Politics — thewere42 @ 7:40 pm

By Jonathan Birchall in New York

Published: November 1 2009 23:55 | Last updated: November 1 2009 23:55

// 0){if (nl.getElementsByTagName(“p”).length>= paraNum){nl.insertBefore(tb,nl.getElementsByTagName(“p”)[paraNum]);}else {if (nl.getElementsByTagName(“p”).length == 3){nl.insertBefore(tb,nl.getElementsByTagName(“p”)[2]);}else {nl.insertBefore(tb,nl.getElementsByTagName(“p”)[0]);}}}}
// ]]>

Walmart has stepped up efforts to mobilise local political support for new store openings in US cities and urban areas that were last month identified as a growth priority for the retailer by Mike Duke, its chief executive.

In addition to a renewed drive to open a second Supercenter store in Chicago, the retailer is also raising its political profile in Philadelphia and continuing to cultivate the ground for a potential move into New York City.

Walmart has long faced political resistance to its plans in the largest US cities, largely orchestrated by the UFCW grocery workers’ union and its political allies. Walmart, the largest US private employer, is strongly anti-union.

Eduardo Castro Wright, chief executive of Walmart’s US stores, has estimated that urban markets where the retailer is under-represented could yield billions of dollars of new sales.

“We already have in our real estate programme a robust plan to go after those,” he told analysts in October. The retailer has only one store inside Chicago’s city limits and none in New York or Boston.

While it has discount stores – which do not sell fresh food – around Philadelphia, Washington DC and Los Angeles, it has only a handful of its more profitable Supercenters near those cities.

The focus on urban markets comes at a time when Walmart’s national reputation has improved, partly as a result of its strong performance during the recession.

Copyright The Financial Times Limited 2009

Article Continues – http://www.ft.com/cms/s/0/8a5ffa1e-c728-11de-bb6f-00144feab49a.html

Implantable Silicon-Silk Electronics

Filed under: Computer Tech, Gadget Tech, Geek Thing, Materials — thewere42 @ 7:40 pm

silkimplant_x220Silicon on silk: This clear silk film, about one centimeter squared, has six silicon transistors on its surface. These flexible devices can be implanted in mice like the one in this image without causing any harm, and the silk degrades over time. The orange liquid on the hair is a disinfectant used during the surgery.  Credit: Rogers/Omenetto

Biodegradable circuits could enable better neural interfaces and LED tattoos.

By Katherine Bourzac

By building thin, flexible silicon electronics on silk substrates, researchers have made electronics that almost completely dissolve inside the body. So far the research group has demonstrated arrays of transistors made on thin films of silk. While electronics must usually be encased to protect them from the body, these electronics don’t need protection, and the silk means the electronics conform to biological tissue. The silk melts away over time and the thin silicon circuits left behind don’t cause irritation because they are just nanometers thick.

“Current medical devices are very limited by the fact that the active electronics have to be ‘canned,’ or isolated from the body, and are on rigid silicon,” says Brian Litt, associate professor of neurology and bioengineering at the University of Pennsylvania. Litt, who is working with the silk-silicon group to develop medical applications for the new devices, says they could interact with tissues in new ways. The group is developing silk-silicon LEDs that might act as photonic tattoos that can show blood-sugar readings, as well as arrays of conformable electrodes that might interface with the nervous system.

Last year, John Rogers, professor of materials science and engineering at the Beckman Institute at the University of Illinois at Champaign-Urbana, developed flexible, stretchable silicon circuits whose performance matches that of their rigid counterparts. To make these devices biocompatible, Rogers’s lab collaborated with Fiorenzo Omenetto and David Kaplan, professors of bioengineering at Tufts University in Medford, MA, who last year reported making nanopatterned optical devices from silkworm-cocoon proteins.

To make the devices, silicon transistors about one millimeter long and 250 nanometers thick are collected on a stamp and then transferred to the surface of a thin film of silk. The silk holds each device in place, even after the array is implanted in an animal and wetted with saline, causing it to conform to the tissue surface. In a paper published in the journal Applied Physics Letters, the researchers report that these devices can be implanted in animals with no adverse effects. And the performance of the transistors on silk inside the body doesn’t suffer.

Article Continues- http://www.technologyreview.com/computing/23847/?a=f

Deriving the Arrow of Time

Filed under: Science Extreme — thewere42 @ 7:40 pm

Wheeler-DeWittThe laws of physics have no preferred direction for time, unless you take quantum cosmology into account.

Humanity has long struggled over the nature of time. In the last century, physicists were shocked to discover that the arrow of time cannot be derived from the laws of physics which appear perfectly symmetric. For every solution for t, there seems to be an equally valid solution for -t (except in a few cases involving the weak force in which case the symmetry is more complex, involving charge, parity and time)

At first glance that looks puzzling. But after a few years reflection, most physicists agreed that it’s perfectly possible for symmetric laws to give rise to asymmetric phenomena. Physicists have identified a number of such asymmetric phenomena that represent “arrows of time”, says Claus Kiefer at the Institut fur Theoretische Physik in Cologne, Germany.

Perhaps the most famous is the thermodynamic arrow of time in which the entropy of a closed system must always increase. But there is also a quantum mechanical arrow of time in which a preferred direction of time is determined by decoherence and a gravitational arrow of time in which the preferred direction is determined by gravitational collapse.

“What is peculiar is the fact that the time direction of the phenomena is always the same,” says Kiefer. It’s almost as if the arrow of time were predetermined in some way. “The question raised by the presence of all these arrows is whether a common master arrow of time is behind all of them,” he asks.

What master law might be responsible? Kiefer’s conjecture is that the direction of time arises when quantum mechanics is applied to the universe as a whole, a branch of science known as quantum cosmology.

Central to this idea is the Wheeler-DeWitt equation that describes the quantum state of the universe as a whole, including both its gravitational and non-gravitational states.

This equation does not contain any parameter that is equivalent to our classical notion of time. In the Wheeler-DeWitt formulation, spacetime does not exist in any classical sense and particles do not have traditional trajectories in spacetime, just as particles do not have traditional trajectories in ordinary quantum mechanics. Instead all the information about the universe is encoded in its wavefunction

So how might an arrow of time arise? While the universe is considered homogeneous to the first degree, there is no preferred direction of time, says Kiefer. But he shows that when small inhomogeneities are taken into account, an asymmetry arises in this wavefunction.

He even says that with slight elaborations, this idea could be applied to an arrow of time in the multiverse.

What he fails to do, however, is provide a way of testing this idea. There is no way of determining experimentally whether the Wheeler-DeWitt formulation is really the origin of the arrow of time.

Of course, that’s a common failure of most thinking about quantum cosmology (not to mention cosmology in general). And until physicists find a way to prune their ideas about time with experimental data, we can merely marvel at their creativity.

Ref: arxiv.org/abs/0910.5836 : Can the Arrow of Time be Understood from Quantum Cosmology?

http://www.technologyreview.com/blog/arxiv/24348/?a=f

An App so You’ll Never Forget

Filed under: Computer Tech, Society — thewere42 @ 7:40 pm

smartfm_x220Remember this: Though originally designed for language learning, Smart.fm’s software has been expanded; now the system can include user-generated material on topics such as the Internet memes shown above.   Credit: Smart.fm

Adaptive-learning algorithms calculate how often people need to see information to remember it.

By Erica Naone

A language-learning application that’s already big in Japan is coming to the U.S. in the form of a new iPhone app. Smart.fm, based in Tokyo, says that the adaptive-learning algorithms behind its software can help users memorize all kinds of information.

Smart.fm is one of several companies selling software designed to help users remember. The company’s algorithms were inspired by research that shows people remember information more effectively they try to memorize it at key times, says founder and chairman Andrew Smith Lewis.

Those algorithms determine how often to present a piece of information to the user and in what context. For example, a completely new word and its translation are shown frequently, and a user is asked relatively easy questions about them, designed to jog the memory. But once the user has demonstrated the ability to recall that word and its meaning, this information will appear less often.

“Efficiency is the main thing,” Lewis says. “We want to optimize the sweet spot between the minimum number of times you have to see an item and the maximum effectiveness of that presentation.”

To use Smart.fm, a person selects an existing list of material–a dictionary of foreign words, for instance–or starts building a new list. The list could be text-only, but the system also supports images and audio. A user might match the names of birds to the sounds they make, or view images of different parts of the human brain in order to learn how to identify them. Someone who snaps pictures of the people she meets at a conference might use the software to commit those people’s names to memory.

“Learning applications which present stimuli adaptively based on the forgetting curve are not new but still relatively rare,” says Peter Brusilovsky, director of the Personalized Adaptive Web Systems Lab at the University of Pittsburgh’s School of Information Sciences. But Smart.fm’s teaching methods can be applied to any type of material, Lewis says. “The adaptive-learning platform doesn’t know if you’re studying Russian painters or chess moves or French verbs,” he says. “It just knows that these are individual objects.”

Unlike other memory applications, Smart.fm takes a social approach, letting users share their lists and add comments to other lists. And in the future, Lewis says, there will be more ways to pull information into the system. The company is working on integrating with Freebase, a site that collects user-generated databases. Once the effort is complete, Smart.fm users who are interested in a particular topic should be able to access information about it from Freebase automatically.

“Education apps are one of the most interesting and growing areas of the iPhone app store,” says Carl Howe, an analyst focusing on mobile research at the Yankee Group. Howe thinks Smart.fm was wise to broaden the scope of its material beyond just language learning. For education apps, he says, “the central aspect is knowing how to engage people’s interest.”

Howe notes that the top education apps for the iPhone are geared toward middle-school and elementary-school children. He believes there’s a huge opportunity for college-level material, too. But companies designing e-learning apps may find themselves competing with material from established universities such as MIT and Stanford, which offer free material for self-directed study online.

Smart.fm’s business model is based largely on the prospect of collaboration with other companies and institutions that want to offer online learning. The company has already partnered with the Japanese telecom giant NTT, which has used the software to create learning sites focusing on specific topics.

Lewis hopes that such deals will become Smart.fm’s main source of revenue, though he also suggests that Smart.fm may offer premium content to users for a price. The iPhone app, however, is and will remain free.

http://www.technologyreview.com/computing/23846/?a=f

Older Posts »

Blog at WordPress.com.