Controlled crumpling of graphene forms artificial muscle

Thursday, January 24, 2013

Duke University engineers are layering atom-thick lattices of carbon with polymers to create unique materials with a broad range of applications, including artificial muscles.

The lattice, known as graphene, is made of pure carbon and appears under magnification like chicken wire. Because of its unique optical, electrical and mechanical properties, graphene is used in electronics, energy storage, composite materials and biomedicine.

However, graphene is extremely difficult to handle in that it easily "crumples." Unfortunately, scientists have been unable to control the crumpling and unfolding of large-area graphene to take advantage of its properties.

Duke engineer Xuanhe Zhao, assistant professor in Duke's Pratt School of Engineering, likens the challenge of controlling graphene to the difference between unfolding paper and wet tissue.

"If you crumpled up normal paper, you can pretty easily flatten it out," Zhao said. "However, graphene is more like wet tissue paper. It is extremely thin and sticky and difficult to unfold once crumpled. We have developed a method to solve this problem and control the crumpling and unfolding of large-area graphene films."

The Duke engineers attached the graphene to a rubber film that had been pre-stretched to many times its original size. Once the rubber film was relaxed, parts of the graphene detached from the rubber while other parts kept adhering to it, forming an attached-detached pattern with a feature size of a few nanometers. As the rubber relaxed, the detached graphene was compressed to crumple. But as the rubber film was stretched back, the adhered spots of graphene pulled on the crumpled areas to unfold the sheet.

"In this way, the crumpling and unfolding of large-area, atomic-thick graphene can be controlled by simply stretching and relaxing a rubber film, even by hands," Zhao said.

The results were published online in the journal Nature Materials.

"Our approach has opened avenues to exploit unprecedented properties and functions of graphene," said Jianfeng Zang, a postdoctoral fellow in Zhao's group and the first author of the paper. "For example, we can tune the graphene from being transparent to opaque by crumpling it, and tune it back by unfolding it."

In addition, the Duke engineers layered the graphene with different polymer films to make a "soft" material that can act like muscle tissues by contracting and expanding on demand. When electricity is applied to the graphene, the artificial muscle expands in area; when the electricity is cut off, it relaxes. Varying the voltage controls the degree of contraction and relaxation.

"The crumpling and unfolding of graphene allows large deformation of the artificial muscle," Zang said.

"New artificial muscles are enabling diverse technologies ranging from robotics and drug delivery to energy harvesting and storage," Zhao said. "In particular, they promise to greatly improve the quality of life for millions of disabled people by providing affordable devices such as lightweight prostheses and full-page Braille displays."

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Duke University: http://www.duke.edu

Thanks to Duke University for this article.

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Source: http://www.labspaces.net/126438/Controlled_crumpling_of_graphene_forms_artificial_muscle

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International adoptions by U.S. parents fall again in 2012

(Reuters) - The number of children adopted internationally by American parents fell 7 percent last year, continuing a multi-year decline brought on in part by tightened adoption rules, a U.S. State Department report showed on Thursday.

Some 8,668 children were adopted into U.S. families from abroad in the 2012 fiscal year, down from 9,320 the previous year, with more children coming from China than from any other country, the report said.

"This is a continuation of a trend," said Adam Pertman, executive director of the Evan B. Donaldson Adoption Institute and the author of "Adoption Nation."

"There's no lack of, if you will, demand in this country," he told Reuters. "People would like to adopt more children; the issue is whether those children are available. And they're becoming less and less available, and that's what the numbers show."

The number of foreign children adopted by U.S. parents peaked in 2004 at 22,884, according to U.S. government figures.

China, which sent 2,697 children to the United States last year, has for years sent more children to American parents than has any other country, in large part due to its one-child policy. Ethiopia was the second most popular country for U.S. adoptions, with 1,568 adoptions last year.

Russia ranked third with 748 children sent to the United States. The report, covering the fiscal year ending on September 30, concluded before Russian President Vladimir Putin signed a law last month banning Americans from adopting Russian children.

The ban is part of a package of legislation that responds to a U.S. law known as the Magnitsky Act, which excludes Russians from the United States who are suspected of involvement in the death in custody of anti-graft lawyer Sergei Magnitsky in 2009 or of other human rights violations.

Russia's Supreme Court has ruled that, in cases where adoptions had been approved by courts before the new year, the children should be handed over to their new parents.

TOUGHENED REGULATIONS

Part of the decline in adoption numbers can be attributed to the signing of the Hague Convention on intercountry adoption, Pertman said.

The convention entered into force for the United States in 2008 and improved regulation of international adoptions to try to cut down on corruption. But it also slowed down adoptions and led to a shutdown in some countries.

The other factor contributing to the decline is that some countries are changing the way they view and handle their intercountry adoptions.

One of those countries is China, which has begun to re-examine whether it can afford to lose the large number of baby girls it allows to leave the country to international adoptive parents, Pertman said.

Most adoptions from China involve girls, because many parents there prefer to have their one child be a boy for social and economic reasons. China has created hurdles for international adoptive parents as it has sought to build up its own domestic adoption program.

As a result of the geopolitical changes making it more difficult for Americans to adopt from abroad, they are having to wait longer to bring a child to the United States, Pertman said. Average wait times are now between two and five years, depending on the country, he said.

"The people who suffer most as a consequence of this are the children who remain in orphanages, who will not have a family in their own country or in the United States," Pertman said.

The largest number of adoptions in the United States continues to come from within the country's foster care system, which accounts for over 50,000 adoptions a year, Pertman said.

(Reporting by Alex Dobuzinskis in Los Angeles; Editing by Eric walsh)

Source: http://news.yahoo.com/international-adoptions-u-parents-fall-again-2012-045031489.html

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Video: Union membership on a decline

>> in the u.s. is on the decline and that could spell trouble for the democratic party . michigan, the latest state to implement right to work laws, that make it more difficult to unionize lost 42,000 union members just last year. total union membership nationwide fell by 400,000 workers last year to 14.3 million, the lowest rate of union membership since the '30s. joining me is chief economist to the afl-cio. thank you for joining us.

>> thank you for having me.

>> you're in "the new york times" article that discusses the workforce and unions and one of the individuals quoted, a professor at clark university and he says it's a time for unions to stop being clever about excuses for why membership is declining and it is time to figure out how to devise appeals to the workers out there. why do you believe these union numbers are dropping so significantly?

>> well, remember, the key to being in the survey is to have a job. and we have a very weak labor market . the big part of that drop came in the public sector and this is the weakest part of the labor market during the recovery. we're losing teachers. this is important not to the union members only but to the nation as a whole because it means that as we have gone through this recovery, we have not been able to make the proper investment to make sure that the kids are educated for the future. and the private sector drop comes in construction and again we know that need to be building the infrastructure to make america successful for the future and the numbers speak a lot about the weakness in the labor market and especially the weakness in the public sector where we know that we need teachers, we know that we need policemen and we need firefighters.

>> correct. it's interesting that you point to the fact that people are out of work and that may be part of the reason you're seeing declining numbers but the professor of the article you're in se should be looking to unions but they're not. so given your point about so many people being out of work, the theory is that they should be looking to unions at a time of insecurity, especially and a lot of places like michigan, for example, and wisconsin, where we know unions believe they've been under attack.

>> unions have been under attack and that's part of the difficulty in getting union membership up. but unions have been very successful reaching out. one of the key number that is showed up in the vort the continued success of the labor movement and organizing latinos . membership among latinos is up. their union density continuing to climb. the diversity shows in the numbers, as well. those are the highest density of membership most likely members of unions are african-americans so when you look at where the union membership is growing, asian americans , african-americans, latinos , the union movement is getting those new workers, the people joining the labor force . and when you look at how unevenness of the recession has affected different states, you see that the union movement is very successful in states right to work states. union membership was up in texas and oklahoma and georgia and north carolina , tennessee. so, it's not -- these numbers are national and patterns of job growth and patterns of job construction taking place and peeling behind the numbers you see the success of the labor movement where people did not expect.

>> it's an interesting article and will continue to follow the numbers and see what this means and impact of upcoming elections. thank you very much, bill.

Source: http://video.msnbc.msn.com/newsnation/50577714/

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Wii U Virtual Console Trial Campaign hands-on

Looking forward to the Wii U's incoming Virtual Console update? No need to wait -- despite the service's post-spring update launch announcement, Nintendo is already rolling out fully functional (and Wii U enhanced) Virtual Console games to the eShop. It's part of the Famicom's 30th anniversary celebration, and gives gamers a chance to sample a handful of Nintendo's best at a hefty discount -- only 30 cents a pop. We tossed a few dimes toward a copy of Balloon Fight to give the upcoming service a quick look.

Gallery: Wii U Virtual Console Trial Campaign

Like all Wii U downloadables, Virtual Console games take up residence on the system menu, flaunting a thumbnail of the game's title screen underlined with a Virtual Console banner. While loading, players are treated to a preview of the game's vitals -- year released, originating console and number of players supported. Easy enough for Balloon Fight: 1984, the Nintendo Entertainment System and two. Within 15 seconds (we're looking forward to that speed update, Nintendo) the game's title screen is mirrored across the gamepad and TV. This is the basic, pure experience -- press start, twiddle the thumbsticks and play the game.

Tapping the gamepad's screen or pressing the ZR button brings up the Virtual Console menu, laying bare the Wii U enhanced features Iwata told us about: restore points and controller settings. 3DS owners should be familiar with the former -- restore points allow you to save your game at any moment and restore it without penalty. Little has changed in the feature's jump to the home console, and usage is straightforward -- just tap the onscreen buttons to save or restore. The Controller settings menu, on the other hand, is new, allowing users to remap the game's controls to their liking. The menu's capabilities are limited, however -- analog sticks and the d-pads won't tolerate reassignment. As promised, playing on the Wii U gamepad is an option, but it isn't necessary. Traditional Wii remotes work just fine, and the tablet-controller's screen can be disabled through the regular Wii U menu. Miiverse is supported too, of course, dropping users into a Balloon Fight community when launched from the game.

The Wii U Virtual Console's official launch may still be a few months off, but based on the first game in the Famicom 30th Anniversary Virtual Console trial campaign, it's shaping up to be a strong evolution of its predecessor. Controller mapping allows users to manually sidestep control issues -- something select games suffered from on the Wii VC when paired with a Gamecube controller. Save states have been a boon to 3DS owners not accustomed to the challenges of classic Nintendo games, and is a welcome addition to the full-sized Virtual Console setup -- after all, how else are we supposed to get a decent score in Balloon Trip mode?

Filed under: Gaming, Nintendo

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Source: http://feeds.engadget.com/~r/weblogsinc/engadget/~3/z5MJFTHb6vk/

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Stylophone S2 portable analog synthesizer hands-on (video)

The original Stylophone is something of a legend. Made popular by David Bowie (and possibly if you're British, Rolf Harris) in the late sixties / early seventies. Since then the original (shown in our gallery) has been re-released, and spin-off products have come to light. The S2, however, represents a new direction for the vintage synth. This time, makers dubreq wanted to create something that maintained the original's pick-up-and-play appeal, while adding some more high-end features and functionality that open it up to more serious sound-smiths. The first thing you will notice is that, while it still has the iconic metal "keys," the Stylophone S2 is somewhat larger -- no bad thing if you've ever tried penning a melody live on the original. Those keys can be triggered with a wireless stylus, but are touch sensitive also, meaning you can poke out a tune without being limited to the agility of your dominant hand. Skip past the break for more details and a hardware video tour.

Gallery: Stylophone S2 hands-on

If you're thinking that, despite being larger than its predecessor, there's just not enough keys, then be assured you can get a full three octaves plus a +/-2 shift function on the left giving it a comprehensive range. The all-analog sound engine also features an eight waveform LFO, bass-heavy sub-oscillators and a state-variable filter. Thanks to an Aux input, you can also use the filters etc. with external audio sources, plus there are headphone and 1/4-inch outputs. If you're worried it's all a little too compact for a live performance, there's a CV (control voltage) input trigger offering the ability to control with with an external sequencing device. It's not all retro though, with the illuminated speaker section also providing real-time feedback (such as the speed of the LFO). Best -- and most importantly of all -- it sounds just like you want it to, full of crunchy, analog goodness. The hardware feels extremely well built, and definitely feels like it could stand up to the knocks and bangs that inevitably come with taking gear out on the road, which, thanks to the option of AA battery power is wonderfully easy. Sound like something you'd like the sound of? The Stylophone S2 is available now for £299 (about $470 by conversion).

Billy Steele contributed to this report.

Filed under: Misc, Peripherals

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Source: http://feeds.engadget.com/~r/weblogsinc/engadget/~3/7GrD394Yj14/

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Video: Swinging blue states: the GOP?s 2016 strategy

How dogs adapted to our starchy diet

Science editor Alan Boyle's blog: Researchers say dogs underwent genetic changes thousands of years ago to adapt to a diet with more starch ? suggesting that domestication might have gone hand in hand with the rise of agriculture.

Source: http://video.msnbc.msn.com/hardball/50554009/

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Russians starts evacuating nationals from Syria

MASNAA, Lebanon (AP) ? Key Syrian ally Russia began evacuating its citizens from the country on Tuesday as the civil war gathered momentum in the capital Damascus with intense fighting around the international airport.

The evacuation was the strongest sign yet of Moscow's waning confidence in the ability of its ally President Bashar Assad to hold onto power. The U.N. chief said Tuesday that a diplomatic conclusion to the war seems unlikely.

U.S. State Department spokeswoman Victoria Nuland said the Russian evacuations indicate "the continued deterioration of the security situation and the violence that Assad is leading against his own people."

Four buses carrying about 80 people, mostly women married to Syrians and their children, crossed out of the country over land into neighboring Lebanon in the early afternoon. The land route was presumably chosen because of renewed fighting near the Damascus airport.

The first of two planes sent to pick up the Russians took off late Tuesday from Beirut and landed shortly after 5 a.m. (0100 GMT) in Moscow. Russia's Emergencies Ministry, which sent the planes, said the passengers were being given medical examinations before leaving the airport. It was unclear if any of them had been injured in the fighting.

Russian announced the beginning of the evacuations on Monday, saying it would take out 100 nationals. The Russian Foreign Ministry says there are tens of thousands of Russians living in Syria. Many of them are Russian women married to Syrian men.

The officials said thousands more evacuations could follow ? possibly by both air and sea.

Russia has been Assad's main ally since the Syrian uprising began in March 2011, selling arms, providing technical support and, along with China, using its veto power in the U.N. Security Council to shield Damascus from international sanctions over the Syrian regime's brutal crackdown on dissent.

But in recent months, Russia has started distancing itself from Assad. President Vladimir Putin said last month that he understands Syria needs change and that he was not protecting the Syrian ruler.

The Russians entered Lebanon at the Masnaa border crossing, where an official from their embassy in Beirut was waiting for them.

Some inside the buses closed the curtains so they would not be seen by journalists waiting at the border. Most refused to comment and those who did speak said only they were going home to visit relatives.

Jodie, an 8-year-old girl traveling from Damascus with her sister and her Syrian father said she was going to Moscow to see her mother, who is Russian. Jodie and her 4-year-old sister Nadine spoke briefly to reporters when they got off the bus to get their passports stamped at the border.

"I used to hear the shelling, but I was not scared," said Nadine. "I would close my eyes."

Officials at the Russian Embassy in Damascus said they have several thousand citizens registered as living in Syria. The officials, speaking on condition of anonymity because they were not authorized to talk to the media, said some of the people who were being evacuated Tuesday have lost their houses and need Russian government assistance to leave.

The officials downplayed the evacuation effort, denying that they are assisting their nationals' departures from Syria because of the deteriorating security situation.

One of the officials, who identified herself only as the embassy's head of protocol, said the government was simply responding to those who had asked for help in leaving Syria, suggesting they were mostly Russians living in areas where the fighting is fiercest.

"It's their personal desire to leave Syria," said the official. She noted that thousands of Russians were still in Syria.

In Moscow, Deputy Foreign Minister Andrei Denisov dismissed reports that the evacuations were the beginning of a Russian exodus from Syria. He told media there Russian planes landed in Beirut to deliver humanitarian aid at the Syrian government's request, and would take home those who wanted to leave.

"There is no plan to take everyone out," Denisov said. "Since the planes have arrived there, and some people with children want to leave, we are ready to take them out."

As the evacuation got under way, Syrian government forces and rebels battled in the suburbs of Damascus and elsewhere.

The Britain-based Syrian Observatory for Human Rights said clashes between opposition fighters and troops were concentrated in the areas around the capital, including along the road linking it to the international airport.

Persistent fighting along the airport road has prompted regional and international airlines to suspend flights to Damascus in recent weeks, although Syrian officials maintain that the airport remains open.

International diplomacy has done little to ease Syria's crisis, which according to the U.N. has claimed more than 60,000 lives since March 2011.

U.N. Secretary-General Ban Ki-moon said he didn't see "much prospect of resolution" by diplomacy.

At his first news conference of the year, Ban noted the worsening humanitarian conditions inside Syria and for those who have fled to neighboring countries.

For months, special envoy Lakhdar Brahimi, who represents the U.N. and the Arab League, has been pushing for a cease-fire and the formation of a transitional government ? with little apparent progress.

Ban said he and Brahimi reached a bleak conclusion after talks Monday.

"Our shared assessment is that we are still a long way from getting the Syrians together," he said.

____

Associated Press writers Albert Aji in Damascus, Syria, Vladimir Isachenkov in Moscow and Bradley Klapper in Washington contributed to this report.

Source: http://news.yahoo.com/russians-starts-evacuating-nationals-syria-195353057.html

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