Stem-cell 'symphony' creates patterns in feathers

Complex and vibrant bird plumage inspired Darwin's concept of sexual selection as well as many a poem and painting. But feather patterns are not directly coded in DNA, and only now has it become clear how birds pull off the feat: it is the result of a tightly choreographed team effort involving stem cells.

The researchers who made the discovery say it could one day help us grow organs from scratch, without the need to put cells on scaffolds that provide the correct shape ? although others are sceptical.

Cheng-Ming Chuong from the University of Southern California in Los Angeles and colleagues found a collection of stem cells at the base of feather follicles that give rise to melanocytes: cells that produce the pigment melanin.

The find mirrors a similar discovery in mammalian hair follicles a decade ago. But hair colour is a one-dimensional property, changing only along the hair's length. In a feather, colour can vary in three dimensions to create stripes or spots in the barbs that can appear different depending on which side of the feather you observe them from.

Looking more closely at the stem cells, Chuong worked out how they are linked with such fine control over feather colour. The cells sit in a ring and work together to change the pattern of melanocytes from the front to the back of the feather follicle, from the centre to the outside of the follicle, and over time as the feather grows.

"Like a symphony"

These three variables interplay with a fourth: production of a peptide called agouti by a layer of peripheral pulp found within feather follicles. Agouti inhibits melanocytes and so generates white ? unpigmented ? regions in the feather. For complex patterns, all four of these variables are "choreographed" at once in an intricate sequence, says Chuong. "You have [something] like a symphony there," he says.

"I think it's a very significant piece of work," says Rick Sturm from the University of Queensland in Brisbane, an expert in human pigmentation. He says he is surprised at the level of stem cell complexity in feather follicles.

The underlying motivation in figuring out how feather patterns are created was to understand how stem cells create complex patterns at all, explains Chuong. "We believe the fundamental principles of organised patterns are shared in different organs."

Melissa Little, also at the University of Queensland, leads research on kidney morphogenesis ? how kidneys get their shape. She thinks it's a stretch to say that the new study will help efforts to grow complex organs.

"We're already asking, how do you get those complex structures?" she says. "I think it's a jump if they think this is applicable to different systems."

Chuong disagrees. "People can take stem cells and make lung cells but they can't make the shape [of a lung]," he says. This month, for example, new kidneys were grown in the lab from stem cells, but they had to be grown on a scaffold obtained from an existing kidney.

"Getting into the control of morphogenesis is really the frontier of stem cell science," says Chuong. "The pigment pattern here is being used because it is experimental and manipulable."

Journal reference: Science, DOI: 10.1126/science.1230374

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Talks on bill to ease FAA furloughs

WASHINGTON (AP) ? With flight delays mounting, White House officials and key members of the Senate reported significant progress Thursday night on legislation to end air traffic controller furloughs blamed for inconveniencing large numbers of travelers.

Under a draft compromise circulated among lawmakers, the Federal Aviation Administration would gain authority to transfer up to $253 million from accounts that are flush into other programs, to "prevent reduced operations and staffing" through the Sept. 30 end of the fiscal year.

Officials said they hoped for passage later in the evening, after most members of the Senate already had left the Capitol to begin a 10-day vacation.

Sen. Susan Collins, R-Maine, a participant in the talks, said the measure would "prevent what otherwise would have been intolerable delays in the air travel system, inconveniencing travelers and hurting the economy."

Earlier, lawmakers involved in the talks said there was general agreement that the FAA should be given additional flexibility in allocating its share of $85 billion in across-the-board spending cuts that took effect last month at numerous federal agencies.

But consensus on the details was elusive, and without legislation, the furloughs and resulting flight delays were virtually certain to persist at least until Congress returns on May 6 after a weeklong vacation.

"I want to do it right now. There are other senators you'd have to ask what the hang-up is," said Sen. Mark Udall, a Colorado Democrat who helped author one of several proposals under consideration.

Any measure that cleared the Senate would also have to be approved by the House. Officials there indicated earlier in the day they were willing to do so, depending on the details.

For the White House and Senate Democrats, the discussions on legislation relating to one relatively small slice of the $85 billion in spending cuts marked a shift in position in a long-running struggle with Republicans over budget issues. Similarly, the turn of events marked at least modest vindication of a decision by the House GOP last winter to finesse some budget struggles in order to focus public attention on the across-the-board cuts in hopes they would gain leverage over President Barack Obama.

The talks unfolded as the FAA said there had been at least 863 flights delayed on Wednesday "attributable to staffing reductions resulting from the furlough."

The Professional Aviation Safety Specialists, a union that represents FAA employees, reported a number of incidents it said were due to the furloughs.

In one case, it said several flights headed for Long Island MacArthur Airport in New York were diverted on Wednesday when a piece of equipment failed. "While the policy for this equipment is immediate restoral, due to sequestration and furloughs it was changed to next-day restoral," the union said.

It added it was "learning of additional impacts nationwide, including open watches, increased restoration times, delays resulting from insufficient funding for parts and equipment, modernization delays, missed or deferred preventative maintenance, and reduced redundancy."

The airlines, too, were pressing Congress to restore the FAA to full staffing.

In an interview Wednesday, Robert Isom, chief operations officer of US Airways, likened the furloughs to a "wildcat regulatory action."

He added, "In the airline business, you try to eliminate uncertainty. Some factors you can't control, like weather. It (the FAA issue) is worse than the weather."

In a shift, first the White House and then senior Democratic lawmakers have signaled a willingness in the past two days to support legislation that alleviates the budget crunch at the FAA, while leaving the balance of the $85 billion to remain in effect.

Obama favors a comprehensive agreement that replaces the entire $85 billion in across-the-board cuts as part of a broader deficit-reduction deal that includes higher taxes and spending cuts.

One Senate Democrat, Sen. Patty Murray of Washington, noted that without the type of comprehensive deficit deal that Obama favors, a bill that eases the spending crunch at the FAA would inevitably be followed by other single-issue measures. She listed funding at the National Institutes of Health as one example, and cuts that cause furloughs of civilians who work at military hospitals as a second.

At the same time, Democratic aides said resolve had crumbled under the weight of widespread delays for the traveling public and pressure from the airlines.

Sen. John Thune, R-S.D., involved in the discussions, said the issue was big enough so "most people want to find a solution as long as it doesn't spend any more money."

Officials estimate it would cost slightly more than $200 million to restore air traffic controllers to full staffing, and another $50 million to keep open smaller air traffic towers around the country that the FAA has proposed closing.

Across the Capitol, the chairman of the House Transportation Committee, Rep. Bill Shuster, R-Pa., said, "We're willing to look at what the Senate's going to propose."

He said he believes the FAA has the authority it needs under existing law to shift funds and end the furloughs of air traffic controllers, and any legislation should be "very, very limited" and direct the agency to use the flexibility it already has.

In a reflection of the political undercurrents, another House Republican, Rep. James Lankford of Oklahoma, said FAA employees "are being used as pawns by this (Obama) administration to be able to implement the maximum amount of pain on the American people when it does not have to be this way."

The White House and congressional Democrats vociferously dispute such claims.

___

Associated Press writers Joan Lowy, Henry C. Jackson and Alan Fram in Washington and David Koenig in Dallas contributed to this report.

Source: http://news.yahoo.com/talks-bill-ease-faa-furloughs-212051561--politics.html

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Task force investigating LA church fire

LOS ANGELES (AP) ? A national task force that investigates arsons at worship facilities is investigating a fire that has gutted a South Los Angeles church.

City Fire Department officials say the blaze early Friday at the Bethesda Temple Apostolic Church appears suspicious.

The fire occurred shortly before 2 a.m. Eighty firefighters were able to knock it down in about 50 minutes.

A task force including the FBI, Los Angeles police and fire, and the U.S. Bureau of Alcohol, Tobacco, Firearms and Explosives is investigating the blaze. The unit was created in 1996 in response to a rash of arsons at African-American churches.

A dog trained to sniff for accelerants is helping in the probe.

The church opened in 1952.

Source: http://news.yahoo.com/task-force-investigating-la-church-fire-162117571.html

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Chemical weapons in Syria? What Obama's high bar for proof could mean

The US reluctance to join with three key allies ? Britain, France, and now Israel ? in concluding that Syria?s Bashar al-Assad has used chemical weapons in his country?s civil war confirms President Obama?s consistent wariness about US intervention in the two-year-old conflict.

Beyond that point, however, former officials and analysts are split over why Mr. Obama is so cautious about the issue ? he even refused to answer a reporter?s question on the topic Tuesday ? and what the apparently high bar the administration has set for evidence of chemical weapons use means.

?It?s a hard call as to whether the administration is trying to avoid something, or if they just don?t have the evidence,? says Wayne White, a former State Department official with experience in Middle East intelligence.

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Obama has said repeatedly since last August that Syria?s use of chemical weapons is a US ?red line? and would be a ?game changer? for the US. But now some critics say the president?s caution suggests a moving or ?fuzzy? red line.

For some, the president is simply being prudent, especially if the evidence presented so far is ?inconclusive,? as a number of senior administration officials, including Defense Secretary Chuck Hagel, have said. Obama, they add, wants to avoid a rush to judgment that turns out to be mistaken ? and which could appear to the world like a repeat of the 2003 US decision to invade Iraq over weapons of mass destruction that didn?t exist.

White House spokesman Jay Carney said Tuesday that the US is being ?extremely deliberate? in investigating and evaluating the reports of chemical weapons use. And on Wednesday in Cairo, Secretary Hagel suggested the US would not be rushed to judgment by allies, saying, ?Suspicions are one thing. Evidence is another.? He then added, ?I think we have to be very careful here before we make any conclusions.?

But for others, the reason Obama is setting the bar high ? in a situation where incontrovertible evidence could remain very difficult to come by ? is because he has no desire to ratchet up US involvement in the Syrian conflict unless forced to.

The danger of this approach, critics say, is that it encourages an increasingly desperate President Assad to test the limits of US reluctance ? perhaps even with limited, hard-to-prove use of some chemical weapons.

And even if some isolated use of chemical weapons is proved, some analysts say, Obama is still unlikely to intervene in Syria in a manner that could tip the scales in the conflict.

?Even if CW [chemical weapons] were used, [the response] will depend a bit on how much and what we?re talking about,? says Mr. White, the former State Department official.

If chemical weapons use is proven ?there will have to be some response from the administration,? he adds, ?but unless it?s indiscriminate use, I don?t see us doing something like a no-fly zone that could really make a difference.?

Given Obama?s pattern to this point of gradually ramping up humanitarian aid and non-lethal material assistance to the rebels, the administration might bow to French and British pressure to approve providing the rebels with arms, White says. ?But something like that, that might have made a difference 18 months ago, won?t be a game-changer now.?

That?s because the rebels are now so divided, and because the groups the US would be willing to arm are not the ones ? specifically the more extremist Islamist factions ? achieving advances against Assad on the battlefield.

White, who is now an adjunct scholar at the Middle East Institute in Washington, says the administration may be ?playing for time,? with its talk of deliberate evaluation of evidence, as it tries to overcome its deep divisions over how the US should approach the complex and ever-deepening Syria crisis.

But it also may be that the ?evidence? its allies have provided the US ? supposedly photos of victims with tell-tale signs of chemical-weapons contact from the Israelis, soil samples in the case of the French and British ? isn?t very convincing.

Secretary of State John Kerry said in Brussels Tuesday that Israeli Prime Minister Benjamin Netanyahu told him in a telephone conversation that he was unable to confirm assertions from Israeli Brig. Gen. Itai Brun, head of research and analysis for Israeli military intelligence, that Syria has used chemical weapons several times since the first of the year.

British military intelligence officials originally reported in late March their finding that Assad?s forces had actually used an intense military-grade tear gas in a reported attack March 19 on the city of Halab. Reports claimed that 30 people died in the attack, but the tear gas is not a chemical weapon and it was not clear what caused the deaths.

White says Iraq?s Saddam Hussein ? who used chemical weapons to kills thousands of Kurds in 1988 ? also used a military grade tear gas known as CS on Iranian troops who were advancing on the southern Iraqi city of Basra in 1982. The gas repelled the Iranian forces but did not kill them by the thousands as a nerve gas would have, White says.

The United Nations has formed an investigative group to go into Syria and determine what chemical weapons if any were used, but so far Assad is not letting the team in. And without such a team on the ground, it may remain impossible to deliver the kind of ?conclusive evidence? the Obama administration says it has yet to see.

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Source: http://news.yahoo.com/chemical-weapons-syria-obamas-high-bar-proof-could-232636199.html

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Astrology Show 5 04/25 by X X Die DrachenhXhle X X | Blog Talk ...

On his show, Comedian Rodney Perry covers arts and entertainment, everything from comedy and politics to music and acting, with his signature comedic slant.

MashUp Radio is a 30-minute podcast that discusses the fusion of technology, life, culture and science. Host Peter Biddle, engineer and executive for Intel?s Atom Software, dishes up a thought-provoking discussion.

Joy Keys provides her listeners with insight to improve their lives mentally, physically, monetarily and emotionally. Past guests on the show have included Meshell Nedegeocello, Blair Underwood, in addition to an impressive list of CEOs, humanitarians and authors.

Host Barry Moltz gets small businesses unstuck. He has founded and run small businesses with a great deal of success and failure for more than 15 years. This is a business radio show where he shares all the craziness of small business. It?s that craziness that actually makes it exciting, interesting and totally unpredictable.

The Bottom Line Sports Show is hosted by former NBA stars Penny Hardaway, Charles Oakley, Mateen Cleaves. Tune in to get the inside scoop on what's happening in sports today.

Hits Radio covers basketball, sports culture and entertainment with past guests including Jason Kidd, Robin Lundberg and Chris Herren.

Listeners get an earful on The Halli Casser-Jayne Show, Talk Radio for Fine Minds. Whether it?s the current political cocktail or the latest must-read award-winning book, Halli tackles all topics and likes to stir ? and sometimes shakes ? things up.

Official Internet radio show of forthcoming epic paranormal investigation book by Eric Olsen and "Haunted Housewife" Theresa Argie.

Award-winning World Footprints is a leading voice in socially responsible travel and lifestyle. Hosts Ian & Tonya celebrate culture and heritage and bring a unique voice to the world of travel.

Football Reporters Online is a group of veteran football experts in the fields of coaching, scouting, talent evaluation, and writing/broadcasting/media placement. Combined, the group brings well over 100 years of expertise in sports.

Host John Martin interviews the nation's leading entrepreneurs and small biz experts to educate small business owners on how to be successful. Past guests have included Emeril Lagasse and Guy Kawasaki.

The Movie Geeks share their passion for the art through interviews with the stars of and creative minds behind your favorite flicks and pay tribute to big-screen legends. From James Cameron and Francis Ford Coppola to Ellen Burstyn and Robert Duvall, The Geeks have got'em all.

Sylvia Global presents global conversations pertaining to women, wealth, business, faith and philanthropy. Sylvia has interviewed an eclectic mix from CEOs and musicians to fashion designers and philanthropists including Randolph Duke and Ne-Yo.

Mr. Media host Bob Andelman goes one-on-one with the hottest, most influential minds from the worlds of film, TV, music, comedy, journalism and literature. That means A-listers like Kirk Douglas, Christian Slater, Kathy Ireland, Rick Fox, Chris Hansen and Jackie Collins.

Paula Begoun, best-selling author of Don't Go to the Cosmetics Counter Without Me, separates fact from fiction on achieving a radiant, youthful complexion at any age. She?s regularly joined by health and beauty experts who offer the latest on keeping your skin in tip-top shape.

Source: http://www.blogtalkradio.com/dragons-lair/2013/04/26/astrology-show-5

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Panasonic gussies up Lumix DMC-XS1 with 10 different designs

It's that time of year again -- the gadgets of CES are finally starting to march into stores. Today's newest catalog item comes from Panasonic in the form of the 16.1-megapixel Lumix DMC-XS1 compact. Equipped with a 24mm wide-angle 5x optical zoom lens, this $200 point-and-shoot is aimed at people looking to move beyond the hazy world of cellphone photography. Unlike some high-end smartphone cameras the DMC-XS1's 1/2.33-inch CCD sensor is limited to 720p video capture at 30 fps. So, it likely won't win over the hardcore paparazzo, but this compact's 10 flashy design options may manage to score some points with fledging shutterbugs.

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In a first, YouTube to showcase a week of comedy

NEW YORK (AP) ? For a week in May, YouTube will turn into the biggest open mic on the planet.

On Thursday, the Google Inc.-owned site will announce the YouTube Comedy Week, a seven-day cyber extravaganza designed to showcase some of the best comedy across its expansive video platform. From May 19-25, YouTube will be overrun with punch lines, sketches, stand-up routines and ? hopefully ? a lot of laughs.

It's the largest-scale attempt yet by YouTube to program its billions of hours of video and lead viewers to its growing channels of original programming. The video site is planning more event weeks around various themes to be held later this year and beyond.

"This has never been done before on YouTube," Danielle Tiedt, YouTube's vice president of marketing, said in an interview Wednesday ahead of the announcement. "I'm sure we'll learn a lot."

Comedy Week will kick off with a global live stream from Los Angeles' Culver Studios. Throughout the week, new episodes will debut from some of YouTube's most popular channels, comedians will perform and comics will curate lists of their favorite videos.

Among those participating are Sarah Silverman, Rainn Wilson, Michael Cera, Vince Vaughn and Seth Rogen. There will be new videos from Andy Samberg's Lonely Island troupe. Popular comedy destinations with channels on YouTube like The Onion, Nerdist, College Humor and Funny or Die will join in. And YouTube hopes its less famous users will also get in on the act.

The event is just the start of a new approach by YouTube to congregate its disparate stars ? from Hollywood professionals to Internet upstarts ? and to present a unified viewing experience for users. YouTube hopes the theme weeks will spotlight the original programming the site has invested hundreds of millions of dollars in to grow its platform as a kind of next-generation TV.

"We're hoping to do this in a pretty regular rhythm," said Tiedt. "You'll see several of these coming from us, for sure, as we highlight really big areas that we think are amazing areas of strength for YouTube."

The undertaking is months in the works. To executive-produce the weeklong event, YouTube brought in former "Jimmy Kimmel Live!" producer Daniel Kellison, whose production company, HaChaCha, recently launched two comedy YouTube channels: Jash and the Video Podcast Network. The kickoff live stream will be directed and produced by Joel Gallen, a veteran of the MTV Movie Awards.

Kellison says a staff of 40 has been assembled to help in what he calls the "tremendously daunting" task of organizing a sizable portion of the sprawling YouTube realm.

"It's a massive undertaking," he says. "If you try to organize it all and figure it all out, you'll drown. It's not possible. We're just doing the best we can in trying to produce this."

A few missteps are inevitable, Kellison says. But the plan isn't to put on a slickly produced show, but something more lo-fi and relaxed.

"We've been able to go to all these comedians and say, 'Hey, we can do whatever we want and have fun doing it,'" says Kellison. "It's taken on this sort of comedy Woodstock type of vibe."

The duo of Eric Wareheim and Tim Heidecker, known as Tim & Eric, will be performing in the festivities. Wareheim, among the founders of Jash, believes Comedy Week will help raise the bar for comedy on YouTube.

"It's going to be higher production value, everyone taking it a little bit more serious rather than a throwaway Internet short ? make it a place where legitimate stuff can be and change the perception of what YouTube can be," Wareheim says. "Tim and I have been using YouTube for our TV shows, our movies ? for everything ? to kind of promote stuff. Now instead of just as a promotional tool, we're using it to really distribute content."

Getting even a segment of YouTube to synchronize would seem a tall order. But marshaling together Comedy Week reminds Kellison of the chaotic first night of "Jimmy Kimmel Live!"

"We had Coldplay on the outdoor stage; Warren Sapp coming in after he won the Super Bowl on a helicopter; Jon Gruden canceling; the fire marshal trying to shut us down; Snoop Dogg with the death threats; and a buzzed George Clooney," he recalls. "I imagine this will be very similar."

___

Follow AP Entertainment Writer Jake Coyle on Twitter at: http://twitter.com/jake_coyle

Source: http://news.yahoo.com/first-youtube-showcase-week-comedy-120037906.html

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