মঙ্গলবার, ৩০ এপ্রিল, ২০১৩

LeapFrog's LeapReader pen teaches reading and writing, on sale in July for $50

LeapFrog's LeapReader pen teaches reading and writing, on sale in July for $50

With its latest device, LeapFrog's continuing to fight the good fight: teaching kids essential skills through the power of consumer electronics. LeapReader's a sort of spiritual successor to the company's Tag line, maintaining the reading tool's pen-like form factor, while adding writing to the equation. The device continues to read out words and sentences, adding in the ability to trace letters and write them out on its special paper. LeapReader encourages kids to trace the lines of letters and then try things on their own, after a couple of goes. The pen's got enough space to hold 40 books or 175 songs, which can be played through an on-board speaker or via a headphone jack on top -- and you can also play books purchased for your Tag device.

Interested parties will be able to pre-order the $50 LeapReader on June 12th. It'll be hitting retail locations and LeapFrog's site early the following month, with a few months to spare before back to school rolls around. The pen's targeted toward kids aged four to eight (and, thankfully, is designed to only write on designated books) and will come in pink and green. Check out a demo video of the device after the break.

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Source: http://www.engadget.com/2013/04/30/leapfrogs-leapreader/?utm_medium=feed&utm_source=Feed_Classic&utm_campaign=Engadget

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Does antimatter fall up or down? First direct evidence of how atoms of antimatter interact with gravity

Apr. 30, 2013 ? The atoms that make up ordinary matter fall down, so do antimatter atoms fall up? Do they experience gravity the same way as ordinary atoms, or is there such a thing as antigravity?

These questions have long intrigued physicists, says Joel Fajans of the U.S. Department of Energy's Lawrence Berkeley National Laboratory (Berkeley Lab), because "in the unlikely event that antimatter falls upwards, we'd have to fundamentally revise our view of physics and rethink how the universe works."

So far, all the evidence that gravity is the same for matter and antimatter is indirect, so Fajans and his colleague Jonathan Wurtele, both staff scientists with Berkeley Lab's Accelerator and Fusion Research Division and professors of physics at the University of California at Berkeley -- as well as leading members of CERN's international ALPHA experiment -- decided to use their ongoing antihydrogen research to tackle the question directly. If gravity's interaction with anti-atoms is unexpectedly strong, they realized, the anomaly would be noticeable in ALPHA's existing data on 434 anti-atoms.

The first results, which measured the ratio of antihydrogen's unknown gravitational mass to its known inertial mass, did not settle the matter. Far from it. If an antihydrogen atom falls downward, its gravitational mass is no more than 110 times greater than its inertial mass. If it falls upward, its gravitational mass is at most 65 times greater.

What the results do show is that measuring antimatter gravity is possible, using an experimental method that points toward much greater precision in future. They describe their technique in the April 30, 2013 edition of Nature Communications.

How to measure a falling anti-atom

ALPHA creates antihydrogen atoms by uniting single antiprotons with single positrons (antielectrons), holding them in a strong magnetic trap. When the magnets are turned off, the anti-atoms soon touch the ordinary matter of the trap's walls and annihilate in flashes of energy, pinpointing when and where they hit. In principle, if the experimenters knew an anti-atom's precise location and velocity when the trap is turned off, all they'd have to do is measure how long it takes to fall to the wall.

ALPHA's magnetic fields don't turn off instantly, however; almost 30-thousandths of a second pass before the fields decay to near zero. Meanwhile flashes occur all over the trap walls at times and places that depend on the anti-atoms' detailed but unknown initial locations, velocities, and energies.

Wurtele says, "Late-escaping particles have very low energy, so gravity's influence is more apparent on them. But there were very few late escaping anti-atoms; only 23 of the 434 escaped after the field had been turned off for 20-thousandths of a second."

Fajans and Wurtele worked with their ALPHA colleagues and with Berkeley Lab associates, UC Berkeley lecturer Andrew Charman and postdoc Andre Zhmoginov, to compare simulations with their data and separate gravity's effects from those of magnetic field strength and particle energy. Much statistical uncertainty remained.

"Is there such a thing as antigravity? Based on free-fall tests so far, we can't say yes or no, " says Fajans. "This is the first word, however, not the last."

ALPHA is being upgraded to ALPHA-2, and precision tests may be possible in one to five years. The anti-atoms will be laser-cooled to reduce their energy while still in the trap, and the magnetic fields will decay more slowly when the trap is turned off, increasing the number of low-energy events. Questions physicists and nonphysicists have been wondering about for more than 50 years will be subject to tests that are not only direct but could be definitive.

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The above story is reprinted from materials provided by DOE/Lawrence Berkeley National Laboratory.

Note: Materials may be edited for content and length. For further information, please contact the source cited above.


Journal Reference:

  1. C. Amole, M. D. Ashkezari, M. Baquero-Ruiz, W. Bertsche, E. Butler, A. Capra, C. L. Cesar, M. Charlton, S. Eriksson, J. Fajans, T. Friesen, M. C. Fujiwara, D. R. Gill, A. Gutierrez, J. S. Hangst, W. N. Hardy, M. E. Hayden, C. A. Isaac, S. Jonsell, L. Kurchaninov, A. Little, N. Madsen, J. T. K. McKenna, S. Menary, S. C. Napoli, P. Nolan, A. Olin, P. Pusa, C. ? Rasmussen, F. Robicheaux, E. Sarid, D. M. Silveira, C. So, R. I. Thompson, D. P. van der Werf, J. S. Wurtele, A. I. Zhmoginov, A. E. Charman. Description and first application of a new technique to measure the gravitational mass of antihydrogen. Nature Communications, 2013; 4: 1785 DOI: 10.1038/ncomms2787

Note: If no author is given, the source is cited instead.

Disclaimer: Views expressed in this article do not necessarily reflect those of ScienceDaily or its staff.

Source: http://feeds.sciencedaily.com/~r/sciencedaily/strange_science/~3/eA2t8irUzyA/130430113429.htm

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Nokia still thinks camera quality is the best way to beat iOS and Android

BERLIN, April 29 (Reuters) - Barcelona will try every trick in the book to overturn a 4-0 first-leg deficit against Bayern Munich in their Champions League semi-final return leg on Wednesday, honorary Bayern president Franz Beckenbauer warned on Monday. Bayern crushed the Spaniards last week in a surprisingly one-sided encounter but Beckenbauer, former player, coach and president of Germany's most successful club, warned that Barcelona were not ready to surrender. "Barca will try everything to throw Bayern off balance," he told Bild newspaper. ...

Source: http://news.yahoo.com/nokia-still-thinks-camera-quality-best-way-beat-174042836.html

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Cardinal CAM: SGA president at the presidential inauguration

Cardinal CAM: SGA president at the presidential inauguration

University of Louisville Student Government Association president Rudy Spencer didn't pass up the opportunity to be a part of history at the inauguration of President Barack Obama on January 20, 2009. This is his video account of history.

Duration: 2:54

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Source: http://php.louisville.edu/news/multimedia/multimedia.php?id=134

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সোমবার, ২৯ এপ্রিল, ২০১৩

President Obama Pokes Fun at Jay-Z & Taylor Swift!

Barack Obama is a controversial president, but we hope everyone can agree on one thing: The guy can land a punchline. At Saturday's annual White House Correspondents Dinner, the president gave a scathingly funny speech, lampooning himself, the press, Congress, and a few A-list celebrities. If he wasn't funnier than the evening's host Conan O'Brien, he definitely gave him a run for his money! Check out Obama's 7 best zingers, including shots at Jay-Z and Taylor Swift, below.

Source: http://www.ivillage.com/obama-jokes-about-jay-z-taylor-swift-correspondents-dinner/1-a-534532?dst=iv%3AiVillage%3Aobama-jokes-about-jay-z-taylor-swift-correspondents-dinner-534532

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শুক্রবার, ১৯ এপ্রিল, ২০১৩

Concert Window, The Netflix For Live Concerts, Gives Fans A New ...

Back in February, we introduced you about EvntLive, a new startup backed by Silicon Valley veterans that?s on a mission to create a scalable platform for broadcasting live concerts, from arenas to small clubs, backed by a library of recorded shows, profiles and music info. Of course, a platform for live concerts isn?t exactly a new idea. In fact, it?s been floating around for years, but those entering the space have been hamstrung to an over-abundance of friction stemming from royalty and licensing issues and having to convince venues to install the technology and hardware ? among other things. As a result, live online music has been slow to take off.

But the EvntLive founders see a new music industry beginning to emerge, in which the new scale of online consumption and distribution channels now allow artists to tap into much larger audiences. In turn, with digital music moving towards free, artists now make most of their money from touring, but because they can only tour so much and play so many venues, the access to new audiences and ticket sales afforded by a live, online platform is becoming more appealing.

EvntLive isn?t the only startup looking to capitalize on this shift. While it remains in private beta, services like Concert Window, StageIt and Qello are live and finding traction. Concert Window co-founder Dan Gurney tells us that the startup is beginning to hit its stride, having quadrupled revenue over the last five months, added a handful of employees and is now broadcasting over 100 live shows each month.

HomepageScreenshot

The startup has been able to do by broadcasting live concerts over the Web, allowing you to listen and watch as the concert happens from the comfort of your couch. To address the friction for venues mentioned above, Concert Window attempts to take the work out of the hands of venue managers ? all the venue needs is an Internet connection.

The startup provides the equipment, camera and cables, and its system controls the broadcast remotely, so, after the initial setup, venues can just kick back and stream whenever they please. No production team required.

On the user experience end, Concert Window has done its best to keep online ticket prices low (under $10, depending on the concert), and distributes two-thirds of ticket sales to the venue and artist, making it a comparable revenue split to iTunes and app stores. Both the video and audio quality are high, which is a must for online concert services, and if you have a good sound system and are lazy like I am, it almost beats being there in person. By addressing these barriers, Concert Window has been able to stream 2,000 concerts with 1,500+ artists at 15 partner venues to date. To really make a dent, it will be key to offer more selection, but it?s a pretty good start.

From the beginning, Concert Window has dealt with licensing and rights hurdles by focusing exclusively on livestreaming, rather than offering both streaming and archiving. This leaves a gap in the experience, and down the road, the startup that takes the cake in this space is going to do both (and do both on mobile), but it will be a long, uphill battle to work out all the minutia with rights holders.

ShowpageScreenshot

Since launching last fall, Concert Window has been focused on building relationships with venues and artists, meaning that design and its UI have taken a backseat. But, today, the startup officially launched a platform-wide redesign and new branding. The startup now offers an HTML5-compatible site, allowing viewers to tap into what it claims is the largest concert volume of any live music platform from their computer, smartphone or tablet.

By offering a mobile experience, a relatively steady stream of concerts and allowing fans to chat with each other and leave feedback for artists, Concert Window hopes its v2.0 can give it a leg up on the competition.

Find Concert Window at home here.


Right now, live concerts are happening all over the country. Concert Window makes it possible to watch them in real time on your computer, laptop, or smartphone. With an exclusive network of partner venues nationwide, Concert Window is at the forefront of the live streaming movement. It serves as a brand-new revenue stream for its partner venues and musicians, who receive a two-thirds share of ticket and subscription profits. Concert Window?s automated tech workflow means that it can scale to...

? Learn more

Source: http://techcrunch.com/2013/04/18/concert-window-the-netflix-for-live-concerts-gives-fans-a-new-mobile-friendly-venue-on-the-web/

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সোমবার, ৮ এপ্রিল, ২০১৩

PFT: Raiders have $45 million in dead money

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As thousands of Davids prepare to take on the sports world?s Goliath in the NFL concussion lawsuits, Goliath has a fairly large stone that he?s about to drop on all of them.

Lost in the sympathy and intrigue generated by 4,200 former pro football players suing the caretakers of the game they played is the fact that the NFL, as it usually does, has some strong legal arguments.? The first one makes its way to Judge Anita Brody?s court in Philadelphia on Tuesday, after the submission of extensive written materials by the lawyers.

The NFL?s threshold position comes from the labor deal.? The league believes that the various Collective Bargaining Agreements negotiated by the players and the league control the situation, and that any claims for failure to protect players from concussions or to disclose to them the risks of concussions should be pursued via the dispute-resolution system created by the CBAs.

?Although the CBAs have changed over time pursuant to the collective bargaining process, every CBA expressly addresses player health and safety and provides grievance procedures for the resolution of disputes,? the league explained in a submission to the court, via the Philadelphia Inquirer.

The former players obviously disagree, but it?s common in situations like this for the employer to argue aggressively and loudly that workers who have banded together to form a union must rely on the less formal system of dispensing justice that the labor agreement creates.? The workers don?t prefer that approach because it removes from the process a jury of lay persons who could be inclined to decide the case based on dynamics other than the law and the facts.

A jury is far more likely to feel sorry for the former players than an arbitrator would.? Likewise, a jury would be much more inclined to resolve doubt in favor of the players, given the perception that the league has more than enough money to pay a verdict.? Throw in the idea that the men who made the game what is it today earned peanuts in comparison to the amounts paid to today?s players and coaches and executives and owners, and it becomes very easy for a jury to sidestep a morass of conflicting scientific contentions and legal arguments and decide to redistribute the wealth based on a visceral notion of fairness.

That?s why the NFL is fighting so hard to push the case from a court of law to arbitration.? And that?s why this initial skirmish in the concussion litigation will have a dramatic impact on the ultimate outcome of the case.

Source: http://profootballtalk.nbcsports.com/2013/04/06/mckenzies-still-a-year-away-from-rebuilding-raiders/related/

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রবিবার, ৭ এপ্রিল, ২০১৩

Miley Cyrus Pot Smoking Pics Allegedly Surface

So we may have to file this under the not-such-a-big-deal category, but the Internet is blazing with a collection of very suspicious pics that sure look like they show Miley Cyrus smoking pot. Let’s start by reminding readers that this is definitely not the first time photos like these have been circulating. Recently, there was a little curiosity sparked by an Instagram photo that showed someone with their faces obscured, smoking what looked like a huge joint. These pics, however, are pretty clear. They show the former Disney star on a balcony in Miami really enjoying a hand-rolled cigarette of some sort. The way that she is holding it, her facial expressions, and her laughter are what seems to seal the deal — but we still can’t prove it. British tab, The Daily Mail, is all over the case, with the simple title “Is Miley Cyrus Smoking a Joint?” They wrote: “The 20-year-old singer was seen inhaling and puffing smoke into the air as she sat outside at her accommodation in Miami, Florida with the brown paper coated item.” I love how they call it “her accommodation.” Anyway, we can definitely read between the lines with these pics. Sure, the [...]

Source: http://feedproxy.google.com/~r/RightCelebrity/~3/zne7vwWHTPE/

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Android v. iOS guide for newbies

If you?re just starting out in app development and trying to choose between the Android or the iOS SDK, this basic guide might be useful.

In tech years, the iOS vs. Android argument seems like it is half a century old and has stretched the limits of human tolerance for passive-aggressive retorts. Since 2008 the ongoing comparisons between these operating systems have been in the spotlight because of the growing Android market and the possible iOS expectation that everything be done through Apple and with Apple products.

To learn more and to read the entire article at its source, please refer to the following page, Android v. iOS guide for newbies- TechRepublic Blogs

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Source: http://feeds.dabcc.com/~r/microsoft-windows-server-desktop-news/~3/4sfOlGWOYDA/article.aspx

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শুক্রবার, ৫ এপ্রিল, ২০১৩

বৃহস্পতিবার, ৪ এপ্রিল, ২০১৩

Angry Birds maker sees profits surge

(AP) ? Mobile game developer Rovio Entertainment Ltd. says the popular Angry Birds franchise helped it double revenue in 2012, with net profit surging more than 55 percent to 55.5 million euros ($71.2 million).

The Finnish company says that sales last year were 152.2 million euros, up from 75.6 million euro a year earlier. Net profit in 2011 was 35.4 million euros.

CEO Mikael Hed says Rovio had a "stellar start" this year after four major game launches in 2012 and the recent release of the Angry Birds Toons animated series, with increased revenue expected from paid games, virtual goods and advertising.

Last year, the company grew by some 300 to 518 employees.

Rovio said Wednesday total game downloads have exceeded 1.7 billion since the December 2009 launch of Angry Birds.

Associated Press

Source: http://hosted2.ap.org/APDEFAULT/495d344a0d10421e9baa8ee77029cfbd/Article_2013-04-03-EU-Finland-Earns-Rovio/id-171f5acab7e2443baa825a5182c964da

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Body representation differs in children and adults

Apr. 4, 2013 ? Children's sense of having and owning a body differs from that of adults, indicating that our sense of physical self develops over time, according to a new study published in Psychological Science, a journal of the Association for Psychological Science.

Many of our senses -- vision, touch, and body orientation -- come together to inform our perception of having and owning a body. Psychological scientist Dorothy Cowie of Goldsmiths, University of London and colleagues hypothesized that there might be age differences in how these processes come together. To test this hypothesis, they relied on a well-known sensory illusion called the "rubber-hand illusion."

In this illusion, the participant sits with their left hand on a table -- but hidden from view. Instead of looking at her real left hand, she looks at a fake left hand. The experimenter sits across the table and strokes the participant's left hand with a paintbrush while also stroking the fake rubber hand. When the paintbrush strokes are matched so that they occur at the same time and in the same place on the two hands, the participant will often feel as if the fake hand is her own, and perceive the touch she feels as arising from the brush she sees stroking the fake hand.

Cowie and colleagues tested children of three different age groups (4-5; 6-7; and 8-9 years old), as well as adult participants. After experiencing the stroking, the participants were asked to close their eyes and point with their right index finger under the table, so that it was directly underneath the left index finger of their actual hand.

Like adults, children were sensitive to whether the vision and touch cues given by stroking were matched on the real and fake hands. When they were matched, all participants experienced the rubber hand illusion, and when they were asked to point towards their real hand, the points drifted closer to the fake hand and farther away from their own hand.

Interestingly, children of all ages responded more strongly to the illusion than did adults. This shows that children rely more than adults on seeing their body in order to determine their sense of physical self; that reliance on vision created a strong bias toward the fake hand that they were looking at.

These findings indicate that there are two distinct processes underlying the sense of the body that develop according to different timetables -- the process driven by seeing touches on the hand develops early in childhood, while the process driven by seeing a hand in front of us doesn't fully develop until later in childhood.

Co-authors on this research include Tamar Makin of the University of Oxford and Andrew J. Bremner of Goldsmiths, University of London.

This research was supported by a grant from the European Research Council and an award from the Royal Society.

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The above story is reprinted from materials provided by Association for Psychological Science.

Note: Materials may be edited for content and length. For further information, please contact the source cited above.


Journal Reference:

  1. D. Cowie, T. R. Makin, A. J. Bremner. Children's Responses to the Rubber-Hand Illusion Reveal Dissociable Pathways in Body Representation. Psychological Science, 2013; DOI: 10.1177/0956797612462902

Note: If no author is given, the source is cited instead.

Disclaimer: This article is not intended to provide medical advice, diagnosis or treatment. Views expressed here do not necessarily reflect those of ScienceDaily or its staff.

Source: http://feeds.sciencedaily.com/~r/sciencedaily/living_well/~3/V1Fbh1VAQu4/130404122457.htm

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বুধবার, ৩ এপ্রিল, ২০১৩

Conn. lawmakers to vote on gun control package

Shoppers leave Hoffman's Gun Center with their purchases in Newington, Conn., Tuesday, April 2, 2013. Customers are packing gun stores around Connecticut following the unveiling of new gun-control legislation, which could take effect as soon as Wednesday evening. (AP Photo/Charles Krupa)

Shoppers leave Hoffman's Gun Center with their purchases in Newington, Conn., Tuesday, April 2, 2013. Customers are packing gun stores around Connecticut following the unveiling of new gun-control legislation, which could take effect as soon as Wednesday evening. (AP Photo/Charles Krupa)

Cars jam the parking lot as shoppers leave Hoffman's Gun Center with their purchases in Newington, Conn., Tuesday, April 2, 2013. Customers are packing gun stores around Connecticut following the unveiling of new gun-control legislation, which could take effect as soon as Wednesday evening. (AP Photo/Charles Krupa)

HARTFORD, Conn. (AP) ? Responding to one of the worst crimes in state history, Connecticut lawmakers were expected to pass a package of gun control and other measures, described by supporters as the most comprehensive in the country.

Debate on the far-reaching legislation, negotiated by Democratic and Republican legislative leaders, was expected to begin late Wednesday morning. It could last for hours. Both gun rights advocates and gun control supporters are expected to show up in large numbers.

Some of the measures would take effect right away, including expansion of the state's assault weapons ban, background checks for all firearms sales, and a ban on the sale or purchase of ammunition magazines holding more than 10 rounds. The bill also addresses mental health and school security measures, including $15 million to help pay for school security infrastructure upgrades.

Gov. Dannel P. Malloy, a Democrat, has said he'll sign the legislation into law, even though it would allow people to keep their high-capacity magazines so long as they're registered with the state by Jan. 1, 2014.

"I think you can make an argument, a strong argument, this is the toughest law passed anywhere in the country," he said.

But gun rights advocates question whether the legislation would have done anything to stop Adam Lanza, the 20-year-old who blasted his way in to the Sandy Hook Elementary School in Newtown on Dec. 24. State police say he fired off 154 shots with a Bushmaster .223-caliber rifle as he gunned down 20 first graders and six educators. He had earlier killed his mother, Nancy, and later committed suicide.

Search warrants of the Lanzas' Newtown home showed it was packed with weapons and ammunition.

"If it did something to prevent this incident, where the fault lies with the individual and the mother, not with the legitimate gun owners in this state, then we could probably support something," said Robert Crook, executive director of the Coalition of Connecticut Sportsmen.

Crook said he expects the bill will pass, predicting it will likely be challenged in court.

Associated Press

Source: http://hosted2.ap.org/APDEFAULT/386c25518f464186bf7a2ac026580ce7/Article_2013-04-03-Gun%20Control-Conn/id-abed00ce144946f386830ecea10bfc4d

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How a neurotransmitter acts to coordinate a compound movement through two different receptors in C. elegans

Apr. 2, 2013 ? New research by scientists at the University of Massachusetts Medical School shows at the single cell level how an external stimulus sets off a molecular chain reaction in the transparent roundworm C. elegans, a process in which a single neurotransmitter coordinates and times two separate actions. These findings shed new light on how neurons translate sensory input into actions and may one day pave the way to understanding how misfiring neurons contribute to motor symptoms in neurological diseases such as Parkinson's disease.

Details of the study were published online by PLOS Biology.

"We've known the broad outline of how a behavior circuit works-a stimulus starts a neuronal cascade, which ultimately activates a muscle cell-for decades," said Mark Alkema, PhD, assistant professor of neurobiology. "The details about how this process works, however, such as which neurotransmitters act through which receptors in which neurons have remained a mystery for even the simplest of behaviors.

"This research provides an answer to the simple question of how the worm turns around and the broader question of how a behavioral sequence is produced on a sub-cellular level. In time, understanding voluntary movement in humans will require answering the same questions about the timing and location of neurons and neurotransmitters-only in the infinitely more complex variety of circuits in the human nervous system," said Dr. Alkema.

Roundworms move by alternately relaxing and contracting ventral and dorsal muscles along both sides of its body. As the animal moves forward, it uses its head to probe for possible threats. A gentle touch to the head of the worm initiates an escape response resulting in the animal ceasing head movements and quickly moving backwards. This initial reaction is closely followed by a deep ventral turn allowing it to move away in the opposite direction.

Earlier studies have shown that tyramine, a monoamine neurotransmitter akin to noradrenaline in humans, is involved in the C. elegans escape response. Specifically, C. elegans have a pair of tyraminergic motor neurons that are essential for coordinating the initial suppression of head movement and the backing response. These neurons release tyramine, which works through a fast-acting ion channel called LGC-55 to inhibit forward movement and relax the neck muscles. How the animal coordinates this movement with the subsequent deep turn that allows it to complete the change in direction and move away from the threat, however, was unknown. In this study, the authors provide evidence that links this initial phase of the escape response to the later stages in which the worm makes a sharp turn and navigates away from the danger.

When C. elegans are placed on a surface containing a high concentration of tyramine they become immobilized. Alkema and colleagues found that this paralysis could be overcome by mutating the C. elegans gene responsible for encoding the G-protein coupled receptor SER-2. Additionally, they found that the SER-2 receptor was active in a set of 13 neurons residing along the ventral nerve cord. The synapses of these neurons were connected to corresponding ventral muscles cells along one side of the worm's body.

Further experiments revealed that the same monoamine neurotransmitter-tyramine-responsible for the initial phase of the escape response was also responsible for activating the slow-acting G-protein coupled receptor SER-2. Activation of this receptor inhibited release of the neurotransmitter GABA and facilitated contraction of the ventral muscles, allowing the animal to complete its turn and resume movement in the opposite direction.

"This study shows how tyramine works through separate receptors to produce a complex behavior requiring the temporal coordination of independent motor programs," said Alkema. "Acting through the fast-acting ionotropic receptor LGC-55, the animal completes the initial movement by ceasing head movement and backing away. At the same time, the slow-acting SER-2 receptor is also being activated by tyramine to complete the turn and facilitate movement in the opposite direction.

"It is the different receptors that allow for the coordination of these actions by the same neurotransmitter," said Alkema. "This indicates that tyramine, much like adrenergic signaling in mammals, coordinates different aspects of the flight response. It's possible that temporally coordinated activation of ionotropic and metabotropic receptors may be a common signaling motif employed across organisms to orchestrate behavioral responses and is something we will be pursing further."

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Story Source:

The above story is reprinted from materials provided by University of Massachusetts Medical School, via EurekAlert!, a service of AAAS.

Note: Materials may be edited for content and length. For further information, please contact the source cited above.


Journal References:

  1. Jamie L. Donnelly, Christopher M. Clark, Andrew M. Leifer, Jennifer K. Pirri, Marian Haburcak, Michael M. Francis, Aravinthan D. T. Samuel, Mark J. Alkema. Monoaminergic Orchestration of Motor Programs in a Complex C. elegans Behavior. PLoS Biology, 2013; 11 (4): e1001529 DOI: 10.1371/journal.pbio.1001529
  2. Richard Robinson. How the Worm Turns, in Molecular Detail. PLoS Biology, 2013; 11 (4): e1001526 DOI: 10.1371/journal.pbio.1001526

Note: If no author is given, the source is cited instead.

Disclaimer: Views expressed in this article do not necessarily reflect those of ScienceDaily or its staff.

Source: http://feeds.sciencedaily.com/~r/sciencedaily/top_news/~3/DiYDz4ju1C4/130402182642.htm

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Video: Microsoft's Gains In Mobile

Sorry, Readability was unable to parse this page for content.

Source: http://www.nbcnews.com/video/cnbc/51406792/

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