Apr. 28, 2013 ? Being pregnant while young is known to protect a women against breast cancer. But why? Research in BioMed Central's open access journal Breast Cancer Research finds that Wnt/Notch signalling ratio is decreased in the breast tissue of mice which have given birth, compared to virgin mice of the same age.
Early pregnancy is protective against breast cancer in humans and in rodents. In humans having a child before the age of 20 decreases risk of breast cancer by half. Using microarray analysis researchers from Basel discovered that genes involved in the immune system and differentiation were up-regulated after pregnancy while the activity of genes coding for growth factors was reduced.
The activity of one particular gene Wnt4 was also down-regulated after pregnancy. The protein from this gene (Wnt4) is a feminising protein -- absence of this protein propels a fetus towards developing as a boy. Wnt and Notch are opposing components of a system which controls cellular fate within an organism and when the team looked at Notch they found that genes regulated by notch were up-regulated, Notch-stimulating proteins up-regulated and Notch-inhibiting proteins down-regulated.
Wnt/Notch signalling ratio was permanently altered in the basal stem/progenitor cells of mammary tissue of mice by pregnancy. Mohamed Bentires-Alj from the Friedrich Miescher Institute for Biomedical Research, who led this study explained, "The down-regulation of Wnt is the opposite of that seen in many cancers, and this tightened control of Wnt/Notch after pregnancy may be preventing the runaway growth present in cancer."
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Fabienne Meier-Abt, Emanuela Milani, Tim Roloff, Heike Brinkhaus, Stephan Duss, Dominique S Meyer, Ina Klebba, Piotr J Balwierz, Erik van Nimwegen and Mohamed Bentires-Alj. Parity induces differentiation and reduces Wnt/Notch signaling ratio and proliferation potential of basal stem/progenitor cells isolated from mouse mammary epithelium. Breast Cancer Research, 2013 (in press) [link]
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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.
Before we left on our year long backpacking journey around the world, I had made some assumptions about the trip. Many assumptions. One of those was that we would play lots of games. I brought a deck of cards thinking we?d play rummy all the time. We played twice. I downloaded a chess app on our iPad thinking I?d finally learn to play. We never opened it. So how did we pass so much time when traveling on planes, buses, and trains? Well Auston slept nearly the entire time, waking to eat a snack and then passing back out. And I read a lot.
Still, we do love playing games back home and I like to think I come from a game-loving family. My mom and sister are always introducing new games to us and some of them are perfect for travelers. As we begin planning some side trips around Spain and France, it?s time to think about excellent game options for traveling light!
Let?s get more creative than a deck of cards. Everyone knows they can bring one and probably should because game options are endless. Of course there are also the games requiring no supplies at all like ?20 Questions? and ?Would You Rather?. If those suit you then great, but if you?re over the typical card and verbal games, then here are some other options to consider adding to your travel luggage for your next trip.
1. Farkle
Courtesy of elversonpuzzle.com/farkle
This is a dice game that was introduced to us by our family when we arrived home from our round-the-world trip. It involves?a bit of luck and little strategy as you roll six dice, keeping the points you want. Then you re-roll the remaining dice while being cautious that if no more scoring dice are rolled, you lose all your points for that round. All you need is at least two players, six dice and a way of keeping score (pen/paper or phone/tablet).?Rules here.
2. Quiddler
Courtesy of boardsillyonline.com
If you?re into word games but don?t fancy traveling around with a whole Scrabble set, then Quiddler is a great option. It?s a card game where the goal is to create words with the highest point value possible beginning the first round with only three cards and working your way up to the final round with ten cards. It can be played with 1-8 players so you can pass the time solo or with some new travel friends. Rules here.
3. Bananagrams
Courtesy of banagrams.net
Another fun word game that?s even more reminiscent of Scrabble is Bananagams, for 2-7 players. Every player works independently and simultaneously to build words from the letter tiles in a crossword format. Once a player has used up all their tiles without any misspellings or incorrect words, that player is declared the winner. Rules here.
4. Pass the Pigs
Courtesy of www.flickr.com/photos/julianhoad/1935174003
This is the only game on the list that we haven?t actually played before but it was recommended to us as fun game that?s convenient for travel as well. All you need is the two pig dice and a way of keeping score. The game is for two to ten players and like Farkle, it?s about pressing your luck. If you roll the pigs in a scoring position (the way they land is worth various points), you decided wether to take the points and end your turn or roll again and risk losing all your points. How lucky do you feel? Rules here.
There you have four great game options that won?t take up the precious remaining space in your travel luggage. Add them to your travel gear and be ready to entertain yourself because you never know when you?ll have a long, boring flight delay!
Have you ever played any of these games? What?d you think? What?s your favorite game to have for your travels? Let us know!
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MIAMI (Reuters) - The Navy sent extra medical personnel to the Guantanamodetention camp because of a growing hunger strike, and the American Medical Association questioned whether doctors were being asked to violate their ethics by force-feeding prisoners.
The reinforcements arrived at the weekend and included about 40 nurses, specialists and hospital corpsmen, who are trained to provide basic medical care, Army Lieutenant Colonel Samuel House, a spokesman for the detention camp said, said on Monday.
He said 100 of the 166 detainees had joined a hunger strike that began in February to protest their continued detention at the Guantanamo Bay U.S. Naval Base in eastern Cuba. Twenty-one of those had lost enough weight that they were being fed liquid supplements via tubes inserted in their noses and down into their stomachs, House said.
Five were in the hospital for observation but did not have life-threatening conditions, he said.
On Thursday, the president of the American Medical Association sent a letter to U.S. Defense Secretary Chuck Hagel reiterating its long-held position that it is a violation of medical ethics to force-feed mentally competent adults who refuse food and life-saving treatment.
The letter from the AMA's president, Dr. Jeremy Lazarus, stopped short of asking Hagel to halt force-feedings at Guantanamo.
It urged the defense secretary "to address any situation in which a physician may be asked to violate the ethical standards of his or her profession."
Hagel had just returned from a trip to the Middle East and it was unclear whether he had seen the letter, said Pentagon spokesman Army Lieutenant Colonel Todd Breasseale.
Asked if military doctors had raised ethical concerns about being asked to perform force-feedings, Breasseale said, "I can tell you there have been no organized efforts, but I cannot speak for individual physicians.
"I can tell you that we will not allow detainees to harm themselves, and this includes attempts at suicide - including self-induced and peer-pressured starvation to death," he said.
The military has said that some prisoners are pressuring others to join the hunger strike, and that some of those being tube-fed occasionally eat regular meals or voluntarily drink nutritional supplements when they are removed from their cell blocks and are alone with medical personnel.
"It has been the case all along," House said. "Some will eat one meal, and are tube-fed during another, while drinking nutrient at another meal ... Once they are approved (for tube-feeding) they are given the choice."
Military officials say the feedings are done gently, using soft, flexible, lubricated tubes.
Attorney David Remes, who was notified by the military that his Yemeni client, Yasin Ismael, was being tube-fed, gave a starkly different description.
"It can be extremely painful. One of my clients said that it's like having a razor blade go down through your nose and into your throat," Remes said.
He said detainees who resist tube-feedings were forcibly removed from their cells by soldiers in riot gear. "It's really like the way you would treat an animal," he said.
All sides blame the hunger strike on detainee frustration over the Obama administration's failure to carry out its promise to close the detention camp by 2010.
(Additional reporting by Lisa Lewnes in Washington; Editing by Kenneth Barry)
PARIS (AP) ? An explosion ripped off the side of a 5-story residential building in France's Champagne country on Sunday, killing at least two people and injuring nine others, officials said. A search for survivors was underway.
More than 100 rescue workers, firefighters, sniffer-dog squads and bomb and gas experts were deployed to the gutted building in a subsidized housing complex in the city of Reims, east of Paris, officials said. Early pictures on the Web site of a local newspaper, L'Union L'Ardennais, showed heaps of debris spilling out of the building onto a grassy esplanade below, with two helmeted people perched up on a crane for a look inside.
Reims mayor Adeline Hazan told France's BFM television that "a very powerful explosion" had taken place, blowing out windows of nearby buildings. She said the bodies of the two people killed remained under the rubble. Hazan said the blast had the earmarks of a possible gas explosion but insisted that only a thorough investigation would determine the exact cause.
Michel Bernard, the top government official in Reims, told The Associated Press that one person was seriously injured. He said the building dated to the 1960s, and an official investigation was under way to determine the cause. He said about 10 of the 40 or so apartments in the building were affected. He said a search for possible survivors under the rubble was under way.
The precariousness of some buildings has come to light internationally in recent days following the collapse Wednesday of an 8-story building in a suburb of Dhaka, Bangladesh, where at least 362 people have been confirmed to have died. Officials there said three of the floors of that building, which had housed garment factories, had been built illegally.
>>>on
september 11th
,
2001
, two
boeing 767
aircraft crashed into the
world trade center towers
in
lower manhattan
. 11 years, 7 months, and
13 days
later, this was found. today wedged in a
narrow gap
between two buildings not far from
ground zero
. this is believed to be part of the
landing gear
of one of those planes. police say they can clearly see a boeing identification number on this newly recovered part of the airplane. the nypd secured the scene as if it were a
crime scene
. after a
health and safety
evaluation is made a decision will be made about whether they should sift the soil in this very narrow alley between the two buildings for the possible
human remains
of victims of the crime committed on 9/11. the part was found about three blocks from the
site of the world trade center
towers. it was found by accident. there was a surveyor inspecteding the rear of one of those two buildings between which the
landing gear
was found wedged. inspecting one of those buildings and totally unexpectedly, ahead this very, very dramatic find. we are posting links to the pictures from the site and the parts themselves
* Huntelaar on target after injury break * Schalke in race for Champions League spot (Updates with quotes, details) BERLIN, April 28 (Reuters) - Klaas-Jan Hunterlaar scored a hat-trick in a fairytale comeback from an injury break to steer Schalke 04 to a 4-1 win over Hamburg SV on Sunday and boost their chances of Champions League action next season. The Dutchman, who had been out with a knee injury since early March, could not have hoped for a better return with Schalke firmly in control of fourth place which leads to the Champions League qualifying rounds. ...
Threatwatch is your early warning system for global dangers, from nuclear peril to deadly viral outbreaks. Debora MacKenzie highlights the threats to civilisation ? and suggests solutions
The US has had a change of heart: its government is now reasonably confident that the Syrian military has used chemical weapons, specifically the nerve agent sarin. But things still don't add up.
On Thursday, in a letter to US senators, a White House spokesman said that US intelligence has decided "with varying degrees of confidence, that the Syrian regime has used chemical weapons on a small scale."
US president Barack Obama has declared chemical weapons (CW) use a "red line" that would elicit a response by the US, potentially embroiling the country in Syria's vicious two-year civil conflict.
Corroborated facts
However, the letter also insists that "intelligence assessments alone are not sufficient ? only credible and corroborated facts... will guide our decision making."
It specifically called for "a comprehensive United Nations investigation that can credibly evaluate the evidence". Those inspectors, however, have still not received permission to enter Syria. Even if they do it is not clear how much evidence of sarin use they will uncover. Obama's red line might be safe for now.
Syrian president Bashar al-Assad is known to possess a massive CW stockpile, considered to be his deterrent to the nuclear threat posed by neighbouring Israel. Allegations of CW use started in July last year, but have been difficult to verify.
A spokesman for Obama declared on 23 April that "we have not come to the conclusion that there has been that use" of CW by either side. The following day, US Defence Secretary Chuck Hagel dismissed CW use in Syria as "suspicions".
Change of heart
The change of heart was based, said the letter, sent 25 April, on "physiological samples" from victims. These were, judging by reports, from an attack by Assad's forces on the city of Homs on 23 December, analysed at the UK's Defence Science and Technology Laboratory in Salisbury, UK; and samples from an attack on 19 March, on the village of Khan al-Aisal outside the northern city of Aleppo, analysed at the US Army's chemical defense lab in Maryland.
Both the Syrian government and the rebels alleged CW were used by the other side at Khan al-Aisal. Assad insisted the rebels had used chlorine, and asked UN secretary-general Ban Ki-Moon to send a formal weapons inspection team. At the same time, rebels charged that Assad had launched the CW attack, as well as one on the village of Ataibah outside Damascus.
Ban declared that all the sites should be investigated. Possibly as a result, the inspection team Assad invited is still waiting in Cyprus for permission from Assad to enter Syria. Some members of the team have already gone home.
Fog of war
There are clearly some chemicals being used in Syria, but footage of victims raise more questions than they answer. After the 23 December attack on Homs, doctors described symptoms that included pin-point pupils and convulsions ? signs of sarin ? but also lethal fluid in the lungs, which is not.
US officials declared in January that the incident involved CS gas, a tear gas used as a riot-control agent. The international convention banning chemical weapons prohibits the use of CS in war, but allows it for riot control; the dividing line is not clear.
Jean-Pascal Zanders of the European Institute of Security Studies in Paris maintains that images circulated on the internet of the alleged attacks do not suggest a nerve gas like sarin. "There are no convulsions or dead bodies," he says, "only single patients being treated in crowded emergency rooms. I'd expect clusters of casualties, and deaths." Moreover, no one seems to have been exposed to nerve agents due to handling victims.
Only one in a series of four such videos "shows any real poisoning symptoms", says Richard Guthrie, an independent CW expert, formally at the Stockholm International Peace Research Institute.
These symptoms appear to be fluid in the lungs and foaming at the mouth. While sarin causes drooling, among other symptoms, it does not cause fluid in the lungs or foaming at the mouth. Many industrial chemicals do and are commonly released when industrial areas are bombed.
Disappearing traces
Zanders says it would be nearly impossible to get chlorine ? effectively bleach, once it dissolves in body fluids ? to levels that would kill more than a dozen fighters, as Assad claims. But no evidence of the chemical should be left for inspectors to find by now.
Traces of sarin should still be detectable in blood or urine, or soil samples, says Amy Smithson of the Monterey Institute for International Studies, using gas chromatography to separate sample components and mass spectroscopy to analyse them.
The problem is, if there is sarin in a sample, where did it come from? Charles Blair of the Federation of American Scientists points out that it would be in the interests of rebel forces to involve the US in their fight against Assad ? and the origins of the samples coming out of Syria cannot be guaranteed.
Some believe a sarin-tainted sample would be hard to fake. For one thing, the US believes Assad controls all of Syria's CW munitions. But that may not be the only source. When the US had chemical weapons, the army, until 1969, gave out small vials of agents, including sarin, to teach soldiers to recognise their smell ? and they were widely distributed. Similar vials used to train Syrian soldiers might have tempted beleaguered rebels.
Additional reporting by Peter Aldhous
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It looks like everyone loves stickers, because following its last update, Path is growing -- fast. The social app is now pulling in a million users a week and has recently topped nine million. It's picked up most of its new chroniclers and message-senders from English and Spanish speaking regions, particularly in South and Central America. In fact, 500,000 Venezuelans decided to start trying the app over a single weekend. According to Path's co-founder, Dave Morin, search features added at the start of the year have increased user traffic by 50 percent, while the addition of extra stickers and filter purchases has meant its making its way up the top-grossing charts too. The chief exec adds that the growth appears to be organic, with users largely split equally across iOS and Android, although there's nothing just yet on Google Glass user numbers.
NAIROBI, Kenya (AP) ? A most-wanted American jihadi in Somalia said Friday that the leader of Islamic extremist rebels in Somali was starting a civil war, just hours after an assassination attempt left the Alabama native with a neck wound.
Omar Hammami posted on Twitter about what he labeled an assassination attempt late Thursday as he was sitting in a tea shop. He posted four pictures, one of which shows his face with blood on his neck and a dark blood-stained t-shirt.
Hammami, one of the two most notorious Americans in overseas jihadi groups, moved from Alabama to Somalia and joined al-Shabab in about 2006. He fought alongside the al-Qaida-linked group for years while gaining fame for posting YouTube videos of jihadi rap songs.
But Hammami had a falling out with al-Shabab and has engaged in a public fight with the group over the last year amid signs of increasing tension between Somalis and foreign fighters in the group. He first expressed fear for his life in an extraordinary web video in March 2012 that publicized his rift with al-Shabab. He said he received another death threat earlier this year that was not carried out.
"Just been shot in neck by shabab assassin. not critical yet," Hammami tweeted late Thursday. On Friday he wrote that the leader of al-Shabab was sending in forces from multiple directions. "we are few but we might get back up. abu zubayr has gone mad. he's starting a civil war," Hammami posted.
Hammami has been a thorn in the side of al-Shabab after accusing the group's leaders of living extravagant lifestyles with the taxes fighters collect from Somali residents. Another Hammami grievance is that the Somali militant leaders sideline foreign militants inside al-Shabab and are concerned only about fighting in Somalia, not globally. Hammami's Friday comment about a civil war could refer to violence between those two groups.
Al-Shabab slapped Hammami publicly in a December Internet statement, saying his video releases are the result of personal grievances that stem from a "narcissistic pursuit of fame." The statement said al-Shabab was morally obligated to stamp out his "obstinacy."
Hammami has enemies on all sides. The U.S. named Hammami to its Most Wanted terrorist list in March and is offering a $5 million reward for information leading to his capture. Al-Shabab fighters are not eligible for the reward.
Along with Adam Gadahn in Pakistan ? a former Osama bin Laden spokesman ? Hammami is one of the two most notorious Americans in jihad groups. He grew up in Daphne, Alabama, a bedroom community of 20,000 outside Mobile. He is the son of a Christian mother and a Syrian-born Muslim father.
Hammami regularly chats on Twitter with a group of American terrorism experts, conversations that are so colloquial and so infused with Americana that many in the counter-terror field have formed a type of digital bond with Hammami.
After Hammami publicized the assassination attempt, one of his Twitter followers, a counter-terrorism expert from Canada, wrote that Hammami had nine lives. Hammami responded with an apparent reference to the movie The Blues Brothers. "'I'm on a mission from God.' minus the blues music," Hammami wrote.
After the shooting, American terrorism expert J.M. Berger, who has a long-running Twitter relationship with Hammami, posted that it looks like Hammami came within a quarter-inch of death. "Perhaps it's time to come in now," Berger tweeted.
Terrorism expert Clint Watts wrote on his blog, Selectedwisdom.com, that the attack proves that Hammami should fear for his life. Watts said Hammami's anti-Shabab social rants were annoying the militant group and he predicted conflict between Somali militants and foreign fighters.
"If there is going to be a war inside Shabaab, I'm guessing it will happen soon," Watts wrote.
NEW DELHI (AP) ? Part of a hospital building collapsed in central India on Friday after its roof came crashing down, injuring at least eight people, an official said.
More than a dozen people were rescued after being trapped in the rubble of the Kasturba Gandhi Hospital in Bhopal, the capital of Madhya Pradesh state, state minister Babu Lal Gaur said. None of the injuries were serious.
Police officer Upendra Jain said about two dozen people were believed to be on the first floor of the women's medical ward when its roof crashed down. The cause of the collapse was not immediately known.
The hospital is operated by state-run Bharat Heavy Electricals Ltd., Gaur said. Bhopal is about 750 kilometers (465 miles) south of New Delhi.
Building collapses are common in India as builders try to cut corners by using substandard materials, and as multistory structures are built with inadequate supervision. The massive demand for housing around cities and pervasive corruption often result in builders adding unauthorized floors or constructing illegal buildings.
Early this month, at least 72 people were killed when an eight-story residential building being constructed illegally near Mumbai, India's financial capital, came crashing down in the worst building collapse in the country in decades.
Another 70 people were injured when the building in the Mumbai suburb of Thane caved in on April 4.
Looking For Video Marketing Help? Try These Tips On For Size
Is your marketing strategy old and tired? You should be if you want to attract more customers. Has video marketing occurred to you? If the answer is no, it?s time to try it out. This is a fantastic method that can reach a lot of people. These video marketing tips can help you see what to do.
Always provide some type of call to action at the end of each video. Lead folks to your products, and tell them what to do to get them. Have concise and clear instructions in the upcoming step to be sure they follow it as soon as they can. Offer an incentive and give a sense of urgency to get viewers to act quickly.
Put your video on the website you run, as well as posting it on video sharing sites. This helps viewers see the content within your web page, while also having an easy access to the actual services or products. Don?t worry about losing views, as Google counts views of a video regardless of whether they are from YouTube itself or embedded on another site.
TIP! Short videos are better than long once. Your viewers? attention will wander if your video rambles on.
Perfection is overrated. You do not have to invest in state-of-the-art equipment in order to create a quality video. More often than not, the computer you currently own will be more than enough to get the job done. You can also use the camera on your smartphone if you need to. Adopt a professional attitude, provide your audience with useful information and edit your video before you release it.
It?s important to be transparent when making videos. You need to appear real. As people become more familiar with you, they will want to buy from you because they trust you. Your face will be permanently linked with the products you sell.
It?s vital that you present yourself as an honest and upstanding person in your videos. Never have a hidden agenda. When attempting to sell one of your products, let them know this. Begin developing relations with your viewers by using the comments feature. Improve your reputation and become known for your expertise in your business? niche by networking on your video page.
TIP! If you do not feel comfortable shooting a video of yourself, consider using screenshots. You might be one of the many people who do not feel comfortable appearing onscreen.
Try having a contest for your videos on your site. These can be funny or serious, depending on what your users want to do. User submitted videos are perfect opportunities for the viewers to take the stand and introduce themselves to their fellow peers online.
Add music. If you think about it, you?ll figure out that music makes videos more appealing. Find music that fits with your message, and put it in your video. This will convert more customers in the long run. In addition, if you hate showing yourself on video, the music can help with this.
Do you have some frequently asked questions that many people want the answers to? Videos are a great way to address these. Providing brief, simple videos as a sort of ?How To Guide? helps to inform and educate your viewers, making them more likely to trust your brand and make a purchase.
TIP! Start your videos by asking a common question or posing a problem that people have probably encountered. By the time you are finished shooting the video, you should have provided amazing solutions and answers that people can really use.
Try to keep your video from sounding like you are selling something. If all of your videos are little more than sales pitches, audiences will lose interest fast. People will want to watch your videos if they provide valuable content, such as useful advice, answers to questions or interesting demonstrations.
It?s a good idea to post a short video that discusses the background of your business. Talk about what products or services you?re selling and why your viewers should register for your mailing list. Give sign-ups a reward, like a coupon or eBook. When your viewers see that there is a real person behind the product, it improves your credibility.
Always begin with a warm greeting when employing video marketing, as this helps to engage your audience. Allow them to get to know you and your business prior to discussing your true intent. Refresh their memory by repeating your personal name and the name of your business as you close your video.
TIP! Experienced video markets know the importance of promptly responding to comments. Sometimes the only thing standing between the customer and a sale is a single, simple question.
Stories appeal to everyone! Do you have any amusing or inspiring stories that you can share about your business? Talk about an event for charity that you helped out with. It is also a great idea to have product endorsements and referrals from your customers about your business if possible.
You should consider using a ?how-to? video to promote your business. Be sure this video provides all the information the viewer needs. Do not try to use the video as a ploy to force viewers to purchase your product as that will only alienate them from your product. People will use your company if you are open and honest and share relevant content with them.
Do not quit video marketing when you don?t get what you want immediately. Obtain feedback from the audience to improve the videos. You will see your videos getting better and better through practice.
TIP! Podcasting is an underused type of video marketing. This can help you make a little money while marketing your videos to a larger list of possible customers.
Time lapse photography is useful when you?re doing video marketing. Run a video camera in your place of business for a day and let it capture raw footage. Then edit it into an amazing video. Customers will enjoy a day in the life of your business.
As you start to know more about video marketing, your understanding of the possibilities will expand. You can do many things with video marketing that can help you gain customers. You can certainly reach a broader audience and boost profits.
TIP! Humor can be a useful tool in video marketing. Boring, dull advertisements are not that interesting to most people.
Get your free website analysis (valued at $97) ? 1-888-513-5974 (tell us that you seen our ad on the website)
NEW YORK (Reuters) - Stock index futures advanced on Thursday, as investors dealt with a raft of earnings, including those of 3M Co, along with data on the labor market.
Dow component ExxonMobil Corp , the largest U.S. company by market capitalization reports its results Thursday, a day after the company boosted its quarterly dividend.
Fellow Dow component 3M Co reported a slight rise in profit on modest growth in sales of its wide array of products, but shares fell 4.1 percent to $103.50 in premarket trading.
Qualcomm Inc lost 5.8 percent to $62.20 before the opening bell after the mobile chipmaker forecast earnings below expectations late Wednesday.
"The focus remains on the fact that companies continue to mostly beat expectations for earnings but also, many are disappointing on the forecast," said Rick Meckler, president of investment firm LibertyView Capital Management in Jersey City, New Jersey.
"So it is leaving investors with mixed feelings with no real reason to sell off stocks but not enough of a reason to really drive it materially higher - that pattern is likely to continue for a while."
Companies expected to post earnings after the close include Amazon.com Inc and Starbucks .
Data on the labor market is due at 8:30 a.m. EDT with the release of weekly initial jobless claims data. Economists in a Reuters survey forecast a total of 351,000 new filings compared with 352,000 in the prior week.
Verizon Communications Inc will be in focus after sources told Reuters it has hired advisers to prepare a possible $100 billion cash and stock bid to take full control of Verizon Wireless from joint venture partner, Vodafone Group Plc . Verizon shares edged up 0.4 percent to $52 in light premarket trade.
S&P 500 futures rose 6.4 points and were above fair value, a formula that evaluates pricing by taking into account interest rates, dividends and time to expiration of the contract. Dow Jones industrial average futures added 46 points and Nasdaq 100 futures gained 13.25 points.
PulteGroup Inc , the No. 2 U.S. homebuilder, returned to a quarterly profit after reporting a loss a year earlier, as it benefited from low mortgage rates. Shares fell 2.5 percent to $19.20 in premarket trade.
Akamai Technologies Inc surged 19.4 percent to $43.08 in premarket trading after the internet content delivery company forecast second-quarter results above analysts' expectations late on Wednesday.
Earnings season has been largely positive, with 68.4 percent of S&P 500 companies that have reported results so far beating expectations, according to Thomson Reuters data through Tuesday morning. Since 1994, 63 percent have surpassed estimates on average, while the beat rate is 67 percent for the past four quarters.
Analysts see earnings growth of 3.1 percent this quarter, up from expectations of 1.5 percent at the start of the month.
European shares edged up on Thursday, with the benchmark FTSEurofirst 300 index rising for a fifth straight session, helped by gains in car maker Volkswagen and telecoms group Vodafone <.eu/>
Asian shares rose, with recovering commodities and views that a run of weak global economic data will encourage major central banks to keep or deepen their monetary stimulus improving risk sentiment.
Apr. 24, 2013 ? A first-ever vaccine created by University of Guelph researchers for gut bacteria common in autistic children may also help control some autism symptoms.
The groundbreaking study by Brittany Pequegnat and Guelph chemistry professor Mario Monteiro appears this month in the journal Vaccine.
They developed a carbohydrate-based vaccine against the gut bug Clostridium bolteae.
C. bolteae is known to play a role in gastrointestinal disorders, and it often shows up in higher numbers in the GI tracts of autistic children than in those of healthy kids.
More than 90 per cent of children with autism spectrum disorders suffer from chronic, severe gastrointestinal symptoms. Of those, about 75 per cent suffer from diarrhea, according to current literature.
"Little is known about the factors that predispose autistic children to C. bolteae," said Monteiro. Although most infections are handled by some antibiotics, he said, a vaccine would improve current treatment.
"This is the first vaccine designed to control constipation and diarrhea caused by C. bolteae and perhaps control autism-related symptoms associated with this microbe," he said.
Autism cases have increased almost sixfold over the past 20 years, and scientists don't know why. Although many experts point to environmental factors, others have focused on the human gut.
Some researchers believe toxins and/or metabolites produced by gut bacteria, including C. bolteae, may be associated with symptoms and severity of autism, especially regressive autism.
Pequegnat, a master's student, and Monteiro used bacteria grown by Mike Toh, a Guelph PhD student in the lab of microbiology professor Emma Allen-Vercoe.
The new anti- C. bolteae vaccine targets the specific complex polysaccharides, or carbohydrates, on the surface of the bug.
The vaccine effectively raised C. bolteae-specific antibodies in rabbits. Doctors could also use the vaccine-induced antibodies to quickly detect the bug in a clinical setting, said Monteiro.
The vaccine might take more than 10 years to work through preclinical and human trials, and it may take even longer before a drug is ready for market, Monteiro said.
"But this is a significant first step in the design of a multivalent vaccine against several autism-related gut bacteria," he said.
Monteiro has studied sugar-based vaccines for two other gastric pathogens: Campylobacter jejuni, which causes travellers' diarrhea; and Clostridium difficile, which causes antibiotic-associated diarrhea.
The research was supported by the Natural Sciences and Engineering Research Council.
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Journal Reference:
Brittany Pequegnat, Martin Sagermann, Moez Valliani, Michael Toh, Herbert Chow, Emma Allen-Vercoe, Mario A. Monteiro. A vaccine and diagnostic target for Clostridium bolteae, an autism-associated bacterium. Vaccine, 2013; DOI: 10.1016/j.vaccine.2013.04.018
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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.
This journalism image provided by Aleppo Media Center AMC which has been authenticated based on its contents and other AP reporting, shows the damaged famed 12th century Umayyad mosque without the minaret, background right corner, which was destroyed by the shelling, in the northern city of Aleppo, Syria, Wednesday April 24, 2013. The minaret of a famed 12th century Sunni mosque in the northern Syrian city of Aleppo was destroyed Wednesday, leaving the once-soaring stone tower a pile of rubble and twisted metal scattered in the tiled courtyard. President Bashar Assad's regime and anti-government activists traded blame for the attack against the Umayyad mosque, which occurred in the heart Aleppo's walled Old City, a UNESCO World Heritage site. It was the second time in just over a week that a historic Sunni mosque in Syria has been seriously damaged. (AP Photo/Aleppo Media Center, AMC)
This journalism image provided by Aleppo Media Center AMC which has been authenticated based on its contents and other AP reporting, shows the damaged famed 12th century Umayyad mosque without the minaret, background right corner, which was destroyed by the shelling, in the northern city of Aleppo, Syria, Wednesday April 24, 2013. The minaret of a famed 12th century Sunni mosque in the northern Syrian city of Aleppo was destroyed Wednesday, leaving the once-soaring stone tower a pile of rubble and twisted metal scattered in the tiled courtyard. President Bashar Assad's regime and anti-government activists traded blame for the attack against the Umayyad mosque, which occurred in the heart Aleppo's walled Old City, a UNESCO World Heritage site. It was the second time in just over a week that a historic Sunni mosque in Syria has been seriously damaged. (AP Photo/Aleppo Media Center, AMC)
COMBO - This combination of two citizen journalist images provided by Aleppo Media Center AMC which has been authenticated based on its contents and other AP reporting, shows at left: the damaged famed 12th century Umayyad mosque without the minaret, background right corner, which was destroyed by the shelling, in the northern city of Aleppo, Syria, Wednesday April 24, 2013; and at right, an undated view of the mosque with is minaret still intact. The minaret of a famed 12th century Sunni mosque in the northern Syrian city of Aleppo was destroyed Wednesday, April; 24, 2013, leaving the once-soaring stone tower a pile of rubble and twisted metal scattered in the tiled courtyard. President Bashar Assad's regime and anti-government activists traded blame for the attack against the Umayyad mosque, which occurred in the heart Aleppo's walled Old City, a UNESCO World Heritage site. It was the second time in just over a week that a historic Sunni mosque in Syria has been seriously damaged. (AP Photo/Aleppo Media Center, AMC)
In this image taken from video obtained from Aleppo Media Center AMC, which has been authenticated based on its contents and other AP reporting, shows the damaged famed 12th century Umayyad mosque, background, which was destroyed by shelling, in the northern city of Aleppo, Syria, Wednesday, April 24, 2013. The minaret of a famed 12th century Sunni mosque in the northern Syrian city of Aleppo was destroyed Wednesday, leaving the once-soaring stone tower a pile of rubble and twisted metal scattered in the tiled courtyard. President Bashar Assad's regime and anti-government activists traded blame for the attack against the Umayyad mosque, which occurred in the heart Aleppo's walled Old City, a UNESCO World Heritage site. It was the second time in just over a week that a historic Sunni mosque in Syria has been seriously damaged. (AP Photo/Aleppo Media Center, AMC)
Map locates Aleppo, Syria, where the minaret of a 12th century mosque was destroyed
This undated citizen journalism image provided by Aleppo Media Center AMC which has been authenticated based on its contents and other AP reporting, shows the minaret of a famed 12th century Umayyad mosque before it was destroyed by the shelling, in the northern city of Aleppo, Syria. The minaret of a famed 12th century Sunni mosque in the northern Syrian city of Aleppo was destroyed Wednesday, April; 24, 2013, leaving the once-soaring stone tower a pile of rubble and twisted metal scattered in the tiled courtyard. President Bashar Assad's regime and anti-government activists traded blame for the attack against the Umayyad mosque, which occurred in the heart Aleppo's walled Old City, a UNESCO World Heritage site. It was the second time in just over a week that a historic Sunni mosque in Syria has been seriously damaged. (AP Photo/Aleppo Media Center, AMC)
BEIRUT (AP) ? The minaret of a landmark 12th century mosque in the northern Syrian city of Aleppo was destroyed Wednesday, leaving the once-soaring stone tower a pile of rubble and twisted metal scattered in the tiled courtyard.
President Bashar Assad's regime and anti-government activists traded blame for the destruction to the Umayyad Mosque, which occurred in the heart Aleppo's walled Old City, a UNESCO World Heritage site.
It was the second time in just over a week that a historic Sunni mosque in Syria has been seriously damaged. Mosques served as a launching pad for anti-government protests in the early days of the country's 2-year-old uprising, and many have been targeted.
Syrian's state news agency SANA said rebels from the al-Qaida-linked Jabhat al-Nusra group blew it up, while Aleppo-based activist Mohammed al-Khatib said a Syrian army tank fired a shell that "totally destroyed" the minaret.
The mosque fell into rebel hands earlier this year after heavy fighting that damaged the historic compound. The area around it, however, remains contested. Syrian troops are about 200 meters (yards) away.
An amateur video posted online by the anti-government Aleppo Media Center activist group showed the mosque's archways, charred from earlier fighting, and a pile of rubble where the minaret used to be.
Standing inside the mosque's courtyard, a man who appears to be a rebel fighter says regime forces recently fired seven shells at the minaret but failed to knock it down. He said that on Wednesday the tank rounds struck their target.
"We were standing here today and suddenly shells started hitting the minaret," the man says. "They (the army) then tried to storm the mosque but we pushed them back."
The video appeared genuine and corresponded to other Associated Press reporting of the events depicted.
The destruction in Aleppo follows a similar incident in the southern city of Daraa, where the minaret of the historic Omari Mosque was destroyed more than a week ago. The Daraa mosque was built during the Islamic conquest of Syria in the days of Caliph Omar ibn al-Khattab in the seventh century.
In that instance as well, the opposition and regime blamed each other for the damage. SANA also accused Jabhat al-Nusra of positioning cameras around the area to record the event in that case.
Syria's civil war, with the use of everything from small arms to artillery and warplanes, poses a grave threat to the country's rich cultural heritage.
Last year, the medieval market in Aleppo, which is located near the Umayyad Mosque, was gutted by fire sparked by fighting last year.
Both rebels and regime forces have turned some of Syria's significant historic sites into bases, including citadels and Turkish bath houses, while thieves have stolen artifacts from museums.
Five of Syria's six World Heritage sites have been damaged in the fighting, according to UNESCO, the U.N.'s cultural agency. Looters have broken into one of the world's best-preserved Crusader castles, Crac des Chevaliers, and ruins in the ancient city of Palmyra have been damaged.
The damage is just part of the wider devastation caused by the country's crisis, which began more than two years ago with largely peaceful protests but morphed into a civil war as the opposition took up arms in the face of a withering government crackdown. The fighting has exacted a huge toll on the country, killing more than 70,000 people, laying waste to cities, towns and villages and forcing more than a million people to flee their homes and seek refuge abroad.
Aleppo, the country's largest city, and Damascus are two of the key fronts in the conflict, which pits the an Assad regime dominated by the president's Alawite sect, an offshoot of Shiite Islam, and a rebel movement drawn primarily from Syria's Sunni Muslim majority.
Aleppo has been carved into rebel- and regime-held zones, while Damascus remains firmly in government hands, although the rebels have established a foothold in the suburbs and hope to use their enclaves there to eventually push into the city itself.
On Wednesday, two mortar rounds slammed into the Damascus suburb of Jaramana, killing at least seven people and wounding dozens, state media and activists said.
The Britain-based Syrian Observatory for Human Rights said the shells hit near a municipality building and a school in Jaramana. The Observatory, which relies on reports from a network of activists on the ground, said 10 people were killed and 30 were wounded in the attacks.
Syrian state-run SANA news agency said seven people were killed in the attack.
The differences in the death tolls could not be immediately reconciled.
Also Wednesday, Syrian church officials said the whereabouts of two bishops kidnapped in northern Syria remain unknown, a day after telling reporters the priests had been released.
Bishop Tony Yazigi of the Damascus-based Greek Orthodox Church said Tuesday that the bishops, both of whom are based in the northern city of Aleppo, had been released. But later on Tuesday, the Syrian Orthodox Patriarchate in the capital said in a statement on its website that it had not received "any official document indicating the (bishops') release."
Gunmen pulled Bishop Boulos Yazigi of the Greek Orthodox Church and Bishop John Ibrahim of the Assyrian Orthodox Church from their car and killed their driver on Monday while they were traveling outside Aleppo. It was not clear who abducted the priests.
But Bishop Yazigi, who is the brother on one of the abductees, said the gunmen are believed to be Chechen fighters from Jabhat al-Nusra group, one of the most powerful of the myriad of rebel factions fighting in Syria. Yazigi declined to say what made it appear that the Nusra Front was involved.
That account corresponded to one provided by the Observatory, which said foreign fighters had abducted the bishops near a checkpoint outside Aleppo. Observatory director Rami Abdul-Rahman said Wednesday that activists in the area where the kidnapping took place say the gunmen were foreign fighters from the Caucuses.
However, the main opposition group, the Syrian National Coalition, condemned the kidnapping and blamed Assad's regime.
In Rome, Pope Francis called for the rapid release of the two bishops. In his appeal Tuesday, the pontiff called the abduction "a dramatic confirmation of the tragic situation in which the Syrian population and its Christian community is living."
There has been a spike in kidnappings in northern Syria, much of which is controlled by the rebels, and around Damascus in recent months. Residents blame criminal groups that have ties to both the regime and the rebels for the abductions of wealthy residents traveling to Syria from neighboring Turkey and Lebanon.
___
Associated Press writers Bassem Mroue and Ryan Lucas contributed to this report.
GE is taking a 10 percent stake and investing $105 million in the Pivotal Initiative, the spin-out from EMC and VMware. GE will work with Pivotal on research and development with the aim of helping customers develop data analytics offerings. GE says its investment aligns with its focus on the “Industrial Internet.” The move shows GE’s investments in developing its own software prowess.?GE and Pivotal will use the?”Global Software Center,” which is headquartered in?San Ramon, Calif.,?to develop a software platform that GE will deliver as a service to industrial customers. According to a press release issued this morning, Pivotal’s platform will serve as a way for the company to launch applications and offer data analytics. The Pivotal technology draws from EMC and VMware’s stable of products and services, either developed internally or acquired.?VMware?s Cloud Foundry PaaS, SpringSource and Gemstone and EMC?s Greenplum and Pivotal Labs groups form the foundation for one ?virtual organization,? with 1,400 employees.?Cetas, VMware?s big data analytics solution, is also part of the group. Pivotal is now calling itself an enterprise Platform as a Service (PaaS), a commentary on the lack of any meaning that can be found with the usual “private cloud,” rhetoric that has become the catch-all phrase for anything “cloud,” in the enterprise. In fact, there is not one reference to private cloud in the press release. Yefim Natis, vice president and distinguished analyst at Gartner, has tepid reviews for Pivotal. He said it is?noteworthy?that Pivotal?separated its application infrastructure technologies (Pivotal) from systems infrastructure (the remaining VMware assets). It’s ambitious and provides an option for IT versus the range of vendors, such as Red Hat and data analytics companies such as MapR, which has been an EMC partner in years past. Integration is a core missing piece, Natis said in a statement. The effort lacks what is widely recognized as an EMC/VMware weakness. And that’s the lack of a truly independent platform similar to Amazon Web Services or even a SaaS offering to integrate data and applications. He further states that the current composition of technologies does not include a high-productivity development platform: The foundation of Pivotal’s application platform, the CloudFoundry CEAP and PaaS, is using a cloud-based model of elasticity, preserving compatibility with many enterprise Java applications. Offering Java or Ruby frameworks as the primary programming model is a far cry in productivity from the cloud-native metadata-driven application PaaS (aPaaS). And it is
EE's just released its Q1 2013 earnings, giving us a look at its first full quarter with 4G services. The carrier says it's on track to its goal of a million 4G customers by the end of the year, thanks to the addition or migration of 318,000 LTE customers since the service launched.. Despite those more profitable clients, however, total service revenue (excluding hardware sales) was down 1.5 percent for the period over last quarter, to £1.42 billion. On one hand, the number of 4G additions could be seen as disappointing considering the company's strong marketing push of the service -- though on the other, the company's only just activated numerous regions, making that one million 4G subscriber goal seem more likely than not. We'll just have to wait a bit longer to see if Brits are really in love with LTE's extra zip -- and willing to pay for it.
Update: This article originally stated that EE added 318,000 4G customers in Q1 this year, but that figure actually represents the number of users the carrier has added since launching its 4G service. five months ago
Nanowires grown on graphene have surprising structurePublic release date: 23-Apr-2013 [ | E-mail | Share ]
Contact: Liz Ahlberg eahlberg@illinois.edu 217-244-1073 University of Illinois at Urbana-Champaign
CHAMPAIGN, Ill. When a team of University of Illinois engineers set out to grow nanowires of a compound semiconductor on top of a sheet of graphene, they did not expect to discover a new paradigm of epitaxy.
The self-assembled wires have a core of one composition and an outer layer of another, a desired trait for many advanced electronics applications. Led by professor Xiuling Li, in collaboration with professors Eric Pop and Joseph Lyding, all professors of electrical and computer engineering, the team published its findings in the journal Nano Letters.
Nanowires, tiny strings of semiconductor material, have great potential for applications in transistors, solar cells, lasers, sensors and more.
"Nanowires are really the major building blocks of future nano-devices," said postdoctoral researcher Parsian Mohseni, first author of the study. "Nanowires are components that can be used, based on what material you grow them out of, for any functional electronics application."
Li's group uses a method called van der Waals epitaxy to grow nanowires from the bottom up on a flat substrate of semiconductor materials, such as silicon. The nanowires are made of a class of materials called III-V (three-five), compound semiconductors that hold particular promise for applications involving light, such as solar cells or lasers.
The group previously reported growing III-V nanowires on silicon. While silicon is the most widely used material in devices, it has a number of shortcomings. Now, the group has grown nanowires of the material indium gallium arsenide (InGaAs) on a sheet of graphene, a 1-atom-thick sheet of carbon with exceptional physical and conductive properties.
Thanks to its thinness, graphene is flexible, while silicon is rigid and brittle. It also conducts like a metal, allowing for direct electrical contact to the nanowires. Furthermore, it is inexpensive, flaked off from a block of graphite or grown from carbon gases.
"One of the reasons we want to grow on graphene is to stay away from thick and expensive substrates," Mohseni said. "About 80 percent of the manufacturing cost of a conventional solar cell comes from the substrate itself. We've done away with that by just using graphene. Not only are there inherent cost benefits, we're also introducing functionality that a typical substrate doesn't have."
The researchers pump gases containing gallium, indium and arsenic into a chamber with a graphene sheet. The nanowires self-assemble, growing by themselves into a dense carpet of vertical wires across the surface of the graphene. Other groups have grown nanowires on graphene with compound semiconductors that only have two elements, but by using three elements, the Illinois group made a unique finding: The InGaAs wires grown on graphene spontaneously segregate into an indium arsenide (InAs) core with an InGaAs shell around the outside of the wire.
"This is unexpected," Li said. "A lot of devices require a core-shell architecture. Normally you grow the core in one growth condition and change conditions to grow the shell on the outside. This is spontaneous, done in one step. The other good thing is that since it's a spontaneous segregation, it produces a perfect interface."
So what causes this spontaneous core-shell structure? By coincidence, the distance between atoms in a crystal of InAs is nearly the same as the distance between whole numbers of carbon atoms in a sheet of graphene. So, when the gases are piped into the chamber and the material begins to crystallize, InAs settles into place on the graphene, a near-perfect fit, while the gallium compound settles on the outside of the wires. This was unexpected, because normally, with van der Waals epitaxy, the respective crystal structures of the material and the substrate are not supposed to matter.
"We didn't expect it, but once we saw it, it made sense," Mohseni said.
In addition, by tuning the ratio of gallium to indium in the semiconductor cocktail, the researchers can tune the optical and conductive properties of the nanowires.
Next, Li's group plans to make solar cells and other optoelectronic devices with their graphene-grown nanowires. Thanks to both the wires' ternary composition and graphene's flexibility and conductivity, Li hopes to integrate the wires in a broad spectrum of applications.
"We basically discovered a new phenomenon that confirms that registry does count in van der Waals epitaxy," Li said.
###
This work was supported in part by the Department of Energy and the National Science Foundation. Postdoctoral researcher Ashkan Behnam and graduate students Joshua Wood and Christopher English also were co-authors of the paper. Li also is affiliated with the Beckman Institute for Advanced Science and Technology, the Micro and Nanotechnology Lab, and the Frederick Seitz Materials Research Lab, all at the U. of I.
Editor's note: To contact Xiuling Li, call 217-265-6354; email xiuling@illinois.edu.
The paper, "InxGa1xAs Nanowire Growth on Graphene: van der Waals Epitaxy Induced Phase Segregation," is available online.
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AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert! system.
Nanowires grown on graphene have surprising structurePublic release date: 23-Apr-2013 [ | E-mail | Share ]
Contact: Liz Ahlberg eahlberg@illinois.edu 217-244-1073 University of Illinois at Urbana-Champaign
CHAMPAIGN, Ill. When a team of University of Illinois engineers set out to grow nanowires of a compound semiconductor on top of a sheet of graphene, they did not expect to discover a new paradigm of epitaxy.
The self-assembled wires have a core of one composition and an outer layer of another, a desired trait for many advanced electronics applications. Led by professor Xiuling Li, in collaboration with professors Eric Pop and Joseph Lyding, all professors of electrical and computer engineering, the team published its findings in the journal Nano Letters.
Nanowires, tiny strings of semiconductor material, have great potential for applications in transistors, solar cells, lasers, sensors and more.
"Nanowires are really the major building blocks of future nano-devices," said postdoctoral researcher Parsian Mohseni, first author of the study. "Nanowires are components that can be used, based on what material you grow them out of, for any functional electronics application."
Li's group uses a method called van der Waals epitaxy to grow nanowires from the bottom up on a flat substrate of semiconductor materials, such as silicon. The nanowires are made of a class of materials called III-V (three-five), compound semiconductors that hold particular promise for applications involving light, such as solar cells or lasers.
The group previously reported growing III-V nanowires on silicon. While silicon is the most widely used material in devices, it has a number of shortcomings. Now, the group has grown nanowires of the material indium gallium arsenide (InGaAs) on a sheet of graphene, a 1-atom-thick sheet of carbon with exceptional physical and conductive properties.
Thanks to its thinness, graphene is flexible, while silicon is rigid and brittle. It also conducts like a metal, allowing for direct electrical contact to the nanowires. Furthermore, it is inexpensive, flaked off from a block of graphite or grown from carbon gases.
"One of the reasons we want to grow on graphene is to stay away from thick and expensive substrates," Mohseni said. "About 80 percent of the manufacturing cost of a conventional solar cell comes from the substrate itself. We've done away with that by just using graphene. Not only are there inherent cost benefits, we're also introducing functionality that a typical substrate doesn't have."
The researchers pump gases containing gallium, indium and arsenic into a chamber with a graphene sheet. The nanowires self-assemble, growing by themselves into a dense carpet of vertical wires across the surface of the graphene. Other groups have grown nanowires on graphene with compound semiconductors that only have two elements, but by using three elements, the Illinois group made a unique finding: The InGaAs wires grown on graphene spontaneously segregate into an indium arsenide (InAs) core with an InGaAs shell around the outside of the wire.
"This is unexpected," Li said. "A lot of devices require a core-shell architecture. Normally you grow the core in one growth condition and change conditions to grow the shell on the outside. This is spontaneous, done in one step. The other good thing is that since it's a spontaneous segregation, it produces a perfect interface."
So what causes this spontaneous core-shell structure? By coincidence, the distance between atoms in a crystal of InAs is nearly the same as the distance between whole numbers of carbon atoms in a sheet of graphene. So, when the gases are piped into the chamber and the material begins to crystallize, InAs settles into place on the graphene, a near-perfect fit, while the gallium compound settles on the outside of the wires. This was unexpected, because normally, with van der Waals epitaxy, the respective crystal structures of the material and the substrate are not supposed to matter.
"We didn't expect it, but once we saw it, it made sense," Mohseni said.
In addition, by tuning the ratio of gallium to indium in the semiconductor cocktail, the researchers can tune the optical and conductive properties of the nanowires.
Next, Li's group plans to make solar cells and other optoelectronic devices with their graphene-grown nanowires. Thanks to both the wires' ternary composition and graphene's flexibility and conductivity, Li hopes to integrate the wires in a broad spectrum of applications.
"We basically discovered a new phenomenon that confirms that registry does count in van der Waals epitaxy," Li said.
###
This work was supported in part by the Department of Energy and the National Science Foundation. Postdoctoral researcher Ashkan Behnam and graduate students Joshua Wood and Christopher English also were co-authors of the paper. Li also is affiliated with the Beckman Institute for Advanced Science and Technology, the Micro and Nanotechnology Lab, and the Frederick Seitz Materials Research Lab, all at the U. of I.
Editor's note: To contact Xiuling Li, call 217-265-6354; email xiuling@illinois.edu.
The paper, "InxGa1xAs Nanowire Growth on Graphene: van der Waals Epitaxy Induced Phase Segregation," is available online.
[ | E-mail | Share ]
?
AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert! system.
GE is taking a 10 percent stake and investing $105 million in the Pivotal Initiative, the spin-out from EMC and VMware. GE will work with Pivotal on research and development with the aim of helping customers develop data analytics offerings. GE says its investment aligns with its focus on the “Industrial Internet.” The move shows GE’s investments in developing its own software prowess.?GE and Pivotal will use the?”Global Software Center,” which is headquartered in?San Ramon, Calif.,?to develop a software platform that GE will deliver as a service to industrial customers. According to a press release issued this morning, Pivotal’s platform will serve as a way for the company to launch applications and offer data analytics. The Pivotal technology draws from EMC and VMware’s stable of products and services, either developed internally or acquired.?VMware?s Cloud Foundry PaaS, SpringSource and Gemstone and EMC?s Greenplum and Pivotal Labs groups form the foundation for one ?virtual organization,? with 1,400 employees.?Cetas, VMware?s big data analytics solution, is also part of the group. Pivotal is now calling itself an enterprise Platform as a Service (PaaS), a commentary on the lack of any meaning that can be found with the usual “private cloud,” rhetoric that has become the catch-all phrase for anything “cloud,” in the enterprise. In fact, there is not one reference to private cloud in the press release. Yefim Natis, vice president and distinguished analyst at Gartner, has tepid reviews for Pivotal. He said it is?noteworthy?that Pivotal?separated its application infrastructure technologies (Pivotal) from systems infrastructure (the remaining VMware assets). It’s ambitious and provides an option for IT versus the range of vendors, such as Red Hat and data analytics companies such as MapR, which has been an EMC partner in years past. Integration is a core missing piece, Natis said in a statement. The effort lacks what is widely recognized as an EMC/VMware weakness. And that’s the lack of a truly independent platform similar to Amazon Web Services or even a SaaS offering to integrate data and applications. He further states that the current composition of technologies does not include a high-productivity development platform: The foundation of Pivotal’s application platform, the CloudFoundry CEAP and PaaS, is using a cloud-based model of elasticity, preserving compatibility with many enterprise Java applications. Offering Java or Ruby frameworks as the primary programming model is a far cry in productivity from the cloud-native metadata-driven application PaaS (aPaaS). And it is
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Public release date: 23-Apr-2013
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