The demands from the finance ministers set the stage for further uncertainty over the long-awaited bailout and debt-restructuring package for Greece. The focus on Sunday will shift to the Greek Parliament, where the euro zone is insisting the program be agreed upon.Gucci belts, cheap gucci belt for men and women outlet 2012."In short, no disbursement [of aid] without implementation," said Jean-Claude Juncker, the Luxembourg prime minister who serves as chairman of the ministers' meeting.
The ministers coupled their demand for Parliamentary action with an insistence that the political leaders of the coalition sign a written pledge to back the program—in an effort to bind political leaders after elections expected as soon as April—and to identify exactly from where €325 million ($431 million) out of more than €3 billion in promised budget cuts this year will come. Mr. Juncker confidently predicted: "The Greek Parliament will not reject the program."
Protesters shout slogans Thursday under a banner that reads 'Unions' during a protest in Athens.
Evangelos Venizelos, the Greek finance minister, put the choice facing Greece in stark terms: "If we see our future and the salvation of the country in the euro zone, in Europe, we must do what we must do in order for the program to definitely be approved…. If our country, our people prefer another political decision that necessarily leads out of the euro zone and therefore outside European integration, we have to say this clearly to ourselves and to our compatriots."
The demands underline the erosion of trust between Greece and its creditors in the euro zone. A further meeting of euro-zone ministers is scheduled for Wednesday to finally sign off on the agreement, assuming the package passes Parliament.
European officials said Mr. Venizelos was criticized harshly by many other ministers, in part because of the way negotiations dragged on to the last minute.
After all-night talks, Greek Prime Minister Lucas Papademos announced a deal early Thursday among the main political parties to cut spending, slash the minimum wage by 22% and cut pension benefits. These measures are the price of a package of new loans and a debt restructuring.
Thursday's political deal in Athens followed protracted overnight negotiations among Greece's main political leaders—from the Socialist, or Pasok, party, the conservative New Democracy party and the small nationalist Laos party—over what measures they were prepared to accept to clinch the bailout deal.
The plan would pave the way for a bond swap between the government and its private-sector creditors that needs to be put in motion soon. A €14.5 billion bond repayment looms March 20; without the bailout in hand, Greece will default on its debt, with potentially catastrophic effects on euro-zone government-bond markets.
Euro Zone Crisis Tracker
See economic, political and markets news from across Europe as governments and financial institutions deal with the continuing debt crisis.
Olli Rehn, the European Union economics commissioner, said the debt-restructuring accord was "practically finalized." He admitted that time for completing the debt swap is running short—"but we are still within the schedule."
Mr. Rehn said a proposal for Greece's bailout receipts to be placed into a special escrow account—so as to guarantee payments to creditors are made before money is directed to the Greek budget—is under serious consideration. The proposal, coming out of Germany, has upset Greek politicians, who view it as a further challenge to Greek sovereignty.
The three political party bosses had earlier agreed to most of the creditors' demands, including private-sector wage cuts and public-sector job cuts, but they were gucci outlet divided over a plan for deep cuts in pension benefits, leaving a €300 million shortfall in this year's budget targets. Officials later said an agreement was reached on how to cover the gap.
The finance ministers' meeting was expected to review the accord and an accompanying debt-restructuring deal aimed at cutting Greece's debt to private creditors by €100 billion. Before agreement on the €130 billion bailout can be completed, the International Monetary Fund must ensure the numbers add up and that the debt restructuring would lower Greece's debt to 120% of gross domestic product by 2020.
"We want to see real implementation of the measures needed by the Greek government and also full commitment of all leaders in Greece for future measures," said Dutch Finance Minister Jan Kees de Jager.
WSJ's Paul Vigna and Charles Forelle join the News Hub to discuss the package of austerity measures agreed to by Greek leaders in an effort to ward off defaulting on its debt obligations. AP Photo/Orestis Panagiotou-pool
German Finance Minister Wolfgang Schäuble, meanwhile, said he is confident Greece will meet a timetable to complete its negotiations on a debt restructuring and its talks with the euro zone on a second bailout in time. "I'm confident the timetable can be met. It's all down to Greece, [but] these are not simple decisions," he said.
The first crack in the government's unity came earlier Thursday with the resignation of Deputy Labor Minister Yannis Koutsoukos. "Our creditors ignored the arguments and factual proposals of the Labor Ministry and those of the finance minister. In an extortionate manner which is completely improper and shameless, they [creditors] imposed measures which demolish the structure of labor relations," he said.
Separately, in the first real admission by top European officials that Portugal's bailout program may need some kind of adjustment, Mr. Schäuble was caught on camera on the sidelines of the Brussels meeting telling his Portuguese counterpart that would be possible once key decisions on Greece are out of the way.
Portugal signed onto a €78 billion three-year bailout program last May. German's Ministry of Finance declined to comment on the comments, which a spokesman said were private.
Greece's Prime Minister Lucas Papademos arrives prior to a critical meeting in Athens on Wednesday.
For Greece, some crucial details are missing in the deal, including how the European Central Bank will participate. The ECB holds an estimated €45 billion or more of Greek government bonds, which it bought at prices substantially below face value, and European officials said the bank had agreed in principle to sell those bonds at below-par prices.
In a news conference on Thursday, ECB President Mario Draghi said the central bank is prohibited from giving direct financial aid to governments. But he said giving up profits it would make if the bonds were paid in full wouldn't break the rules. "If the ECB distributes part of its profits to its member countries as part of the capital key, that's not monetary financing," he said.
Even if Greece avoids a disorderly default, years of sharp spending cuts and tax increases are having devastating effects on the Greek economy.
Policemen stand behind a banner at a rally at police headquarters in Athens on Thursday.
Greece's unemployment rate soared in November to 20.9%, compared with an 18.2% rate just a month earlier and up sharply from one year ago, Elstat, the 2012 gucci belts cheap sale light blue beige government statistics agency, reported Thursday. The total number of unemployed reached 1.029 million, up 126,062 from October, Elstat said.
The new cuts have the country's unions up in arms. Greece's public and private-sector umbrella unions on Thursday called a 48-hour general strike, following protests by thousands of workers earlier this week.
2012年2月8日星期三
Greek Prime Minister Lucas Papademos
The MSCI Asia Pacific Index sank 0.9 percent as of 10:40 a.m. in Tokyo, paring yesterday’s 1.3 percent rally. Standard & Poor’s 500 Index futures slipped 0.4 percent. The euro declined 0.1 percent and South Korea’s won dropped against 15 of its 16 major counterparts.Cheap burberry - designer bags, shoes, accessories, clothing outlet 2012. Bond risk in Asia rose for the first time this month.
Greek Prime Minister Lucas Papademos and three party leaders “agreed on all the points of the program with the exception of one which requires further elaboration and discussion” with the so-called troika of lenders, according to a statement from the premier’s office. Chinese consumer prices rose 4.5 percent in January from a year earlier, exceeding the median 4 percent estimate in a Bloomberg survey. Japan’s machinery orders fell more than projected in December and New Zealand’s employment growth slowed last quarter, reports showed.
Global stocks entered a bull market yesterday as the MSCI All-Country World Index extended its gain from its October low to 20 percent. Rio Tinto Ltd., Acer Inc. and Tata Steel Ltd. are among Asian companies scheduled to report earnings today. Profits beat projections at 25 percent of the 316 companies in the MSCI Asia Pacific Index that released quarterly results since Jan. 9, according to data compiled by Bloomberg.
Japan’s Topix Index declined 0.6 percent. Machinery orders, an indicator of capital spending, fell 7.1 percent from the previous month, the Cabinet Office said. The median of 29 economists surveyed by Bloomberg News was for a 5 percent decline.
Nissan Motor Co. fell 1.8 percent. Japan’s second-biggest automaker reported third-quarter operating profit that missed analysts’ estimates. The automaker’s European operations had a 1.4 billion yen loss in the quarter as a debt crisis sapped demand, according to a statement from the company.
The Hang Seng China Enterprises Index of mainland companies listed in Hong Kong dropped 1.3 percent. China’s one-year swap rate, the fixed cost to receive the seven-day repurchase rate, climbed 15 basis points to 3.40 percent, according to data compiled by Bloomberg.
The euro weakened to $1.3242. Greek leaders have effectively agreed on all the issues except for that of cuts to pensions, Panos Beglitis, a spokesman for the Pasok socialist party, told reporters. He said his party was opposed to cuts in main pensions.
Consumer prices rose 4.5 percent from a year earlier, the National Bureau of Statistics said on its website today. That was more than all 33 forecasts in a Bloomberg News survey of economists and a median of 4 percent.
Asian stocks fell and Chinese interest-rate swaps jumped as inflation quickening for the first time in six months added pressure on officials to refrain from any immediate additional cut in banks’ reserve requirements. Burberry kids skirts, cheap burberry skirts for girls sale. The government may wait to see data free from holiday distortions and monitor the effect of yesterday’s increase in retail fuel charges before deciding on the next policy move.
“This cuts into the room for monetary policy easing for now,” said Yao Wei, a Hong Kong-based economist with Societe Generale AG. “However, inflation should resume its decline in February and beyond.”
The one-year swap rate, the fixed cost to receive the seven-day repurchase rate, climbed 15 basis points to 3.40 percent after the release, according to data compiled by Bloomberg. The MSCI Asia Pacific Index fell 0.6 percent as of 11:32 a.m. in Tokyo. The Shanghai Composite Index (SHCOMP) slipped 0.3 percent.
Jump in Food Costs
In December, inflation was 4.1 percent. The Chinese New Year holiday, which ran from Jan. 22 to Jan. 28, boosts prices and retail sales while curbing trade and industrial production. Food costs rose 10.5 percent from a year earlier, up from 9.1 percent in December, today’s report showed.
Starbucks Inc. and McDonald’s Corp. have raised prices on wage and commodity costs and officials plan to boost minimum pay rates nationwide by more than 13 percent annually from 2011 to 2015, according to a government plan released this week.
An increase in fuel prices is to spur production by refiners including China Petroleum & Chemical Corp. and PetroChina Co. (857)
“Monetary easing may hold off for one month as the government awaits signs of normalization of the inflation dynamics distorted by the holiday,” said Ding Shuang, a Hong Kong-based economist with Citigroup Inc. He estimates inflation may cool to 4 percent or lower this month.
Factory Prices
Producer-price (CHEFTYOY) inflation eased to 0.7 percent in January from a year earlier after a 1.7 percent gain in December, a separate report from the statistics bureau showed today. That data, too, is distorted by the timing of the holiday.
“It’s comforting that PPI is still decelerating which means upstream pressure is coming down,” Wang Tao, a Hong Kong- based economist with UBS AG, said in a Bloomberg Television interview.
The central bank cut lenders’ reserve requirements in December for the first time in three years to boost credit amid moderating overseas sales. The People’s Bank of China this week pledged to ensure loans for first-home buyers as a crackdown on speculation threatens to trigger a slump in the property market.
China should consider fiscal stimulus if Europe’s burberry best womens windbreaker sale 2012 black crisis sparks a recession there that affects the U.S., Asian Development Bank Managing Director-General Rajat Nag said in Tokyo yesterday.
“Countries, particularly China, have to consider the possibility of coming in with necessary fiscal stimulus if the euro zone crisis becomes more serious and if the effects of that spill over into the U.S.,” he said.
Greek Prime Minister Lucas Papademos and three party leaders “agreed on all the points of the program with the exception of one which requires further elaboration and discussion” with the so-called troika of lenders, according to a statement from the premier’s office. Chinese consumer prices rose 4.5 percent in January from a year earlier, exceeding the median 4 percent estimate in a Bloomberg survey. Japan’s machinery orders fell more than projected in December and New Zealand’s employment growth slowed last quarter, reports showed.
Global stocks entered a bull market yesterday as the MSCI All-Country World Index extended its gain from its October low to 20 percent. Rio Tinto Ltd., Acer Inc. and Tata Steel Ltd. are among Asian companies scheduled to report earnings today. Profits beat projections at 25 percent of the 316 companies in the MSCI Asia Pacific Index that released quarterly results since Jan. 9, according to data compiled by Bloomberg.
Japan’s Topix Index declined 0.6 percent. Machinery orders, an indicator of capital spending, fell 7.1 percent from the previous month, the Cabinet Office said. The median of 29 economists surveyed by Bloomberg News was for a 5 percent decline.
Nissan Motor Co. fell 1.8 percent. Japan’s second-biggest automaker reported third-quarter operating profit that missed analysts’ estimates. The automaker’s European operations had a 1.4 billion yen loss in the quarter as a debt crisis sapped demand, according to a statement from the company.
The Hang Seng China Enterprises Index of mainland companies listed in Hong Kong dropped 1.3 percent. China’s one-year swap rate, the fixed cost to receive the seven-day repurchase rate, climbed 15 basis points to 3.40 percent, according to data compiled by Bloomberg.
The euro weakened to $1.3242. Greek leaders have effectively agreed on all the issues except for that of cuts to pensions, Panos Beglitis, a spokesman for the Pasok socialist party, told reporters. He said his party was opposed to cuts in main pensions.
Consumer prices rose 4.5 percent from a year earlier, the National Bureau of Statistics said on its website today. That was more than all 33 forecasts in a Bloomberg News survey of economists and a median of 4 percent.
Asian stocks fell and Chinese interest-rate swaps jumped as inflation quickening for the first time in six months added pressure on officials to refrain from any immediate additional cut in banks’ reserve requirements. Burberry kids skirts, cheap burberry skirts for girls sale. The government may wait to see data free from holiday distortions and monitor the effect of yesterday’s increase in retail fuel charges before deciding on the next policy move.
“This cuts into the room for monetary policy easing for now,” said Yao Wei, a Hong Kong-based economist with Societe Generale AG. “However, inflation should resume its decline in February and beyond.”
The one-year swap rate, the fixed cost to receive the seven-day repurchase rate, climbed 15 basis points to 3.40 percent after the release, according to data compiled by Bloomberg. The MSCI Asia Pacific Index fell 0.6 percent as of 11:32 a.m. in Tokyo. The Shanghai Composite Index (SHCOMP) slipped 0.3 percent.
Jump in Food Costs
In December, inflation was 4.1 percent. The Chinese New Year holiday, which ran from Jan. 22 to Jan. 28, boosts prices and retail sales while curbing trade and industrial production. Food costs rose 10.5 percent from a year earlier, up from 9.1 percent in December, today’s report showed.
Starbucks Inc. and McDonald’s Corp. have raised prices on wage and commodity costs and officials plan to boost minimum pay rates nationwide by more than 13 percent annually from 2011 to 2015, according to a government plan released this week.
An increase in fuel prices is to spur production by refiners including China Petroleum & Chemical Corp. and PetroChina Co. (857)
“Monetary easing may hold off for one month as the government awaits signs of normalization of the inflation dynamics distorted by the holiday,” said Ding Shuang, a Hong Kong-based economist with Citigroup Inc. He estimates inflation may cool to 4 percent or lower this month.
Factory Prices
Producer-price (CHEFTYOY) inflation eased to 0.7 percent in January from a year earlier after a 1.7 percent gain in December, a separate report from the statistics bureau showed today. That data, too, is distorted by the timing of the holiday.
“It’s comforting that PPI is still decelerating which means upstream pressure is coming down,” Wang Tao, a Hong Kong- based economist with UBS AG, said in a Bloomberg Television interview.
The central bank cut lenders’ reserve requirements in December for the first time in three years to boost credit amid moderating overseas sales. The People’s Bank of China this week pledged to ensure loans for first-home buyers as a crackdown on speculation threatens to trigger a slump in the property market.
China should consider fiscal stimulus if Europe’s burberry best womens windbreaker sale 2012 black crisis sparks a recession there that affects the U.S., Asian Development Bank Managing Director-General Rajat Nag said in Tokyo yesterday.
“Countries, particularly China, have to consider the possibility of coming in with necessary fiscal stimulus if the euro zone crisis becomes more serious and if the effects of that spill over into the U.S.,” he said.
2012年2月7日星期二
Breads and rolls aren't really saltier
That surprising finding comes in a government report released Tuesday that includes a list of the top 10 sources of sodium. Salty snacks actually came in at the bottom of the list compiled by the Centers for Disease Control and Prevention.Gucci outlet, cheap gucci online, gucci 2012 new arrivals for sale.
"Potato chips, pretzels, and popcorn — which we think of as the saltiest foods in our diet — are only No. 10," said CDC Director Dr. Thomas Frieden.
Breads and rolls aren't really saltier than many of the other foods, but people tend to eat a lot of them, said Mary Cogswell, a CDC senior scientist who co-authored the report.
Salt is the main source of sodium for most people, and sodium increases the risk of high blood pressure, a major cause of heart disease and stroke. Health officials say most Americans get too much salt, mostly from processed and restaurant foods — not added from the salt shaker.
Experts have known that the sodium in breads and certain other foods can add up, but even CDC officials were amazed that just 10 foods are responsible for 44 percent of the sodium consumed.
"It's possible to eat a whole bunch of sodium without it seeming salty," noted John Hayes, an assistant professor of food science at Penn State, who was not involved in the report.
According to the CDC, breads and rolls account for about 7 percent of the salt that the average American eats in a day. Next on the list: cold cuts and cured meats; pizza; fresh and processed poultry; soups; fast-food hamburgers and sandwiches and cheese.
Rounding out the list — and accounting for about 3 percent each — are spaghetti and other pasta dishes; meatloaf and other meat dishes and snacks like potato gucci outlet chips and pretzels.
Dietary guidelines recommend no more than 2,300 milligrams of sodium a day, equal to about a teaspoon of salt. Certain people, such as those with high blood pressure, should eat even less. But average sodium consumption in the U.S. is around 3,300 milligrams, the CDC study found. Only 1 in 10 Americans meet the teaspoon guideline.
The amount of sodium in food types can vary. For example, a slice of white bread can have between 80 and 230 milligrams of sodium. A cup of canned chicken noodle soup has between 100 and 940 milligrams and 3 ounces of luncheon meat has between 450 and 1,050 milligrams. A small 1 ounce bag of potato chips ranges from 50 to 200 milligrams.
The new CDC report is based on surveys of more than 7,200 people in 2007 and 2008, including nearly 3,000 children. Participants were surveyed twice, each time answering detailed questions about what they had eaten over the previous day. Researchers then broke down what they ate into categories, and assigned sodium amounts.
Salt reduction has become a recent focus of public health campaigns, and some major food makers have taken steps or announced plans to gradually reduce sodium in their products.
CDC officials — who have long encouraged people to eat more fruits and vegetables — stopped short of advising people to lay off the bread. But they are encouraging consumers to read labels and, for example, buy brands of bread that have lower sodium.
"People can choose how much salt to add to their food at the table. They can't take it out once it's there," Frieden said.Gucci wallets, cheap gucci wallets 2012 outlet for men and women.
There's another way to consume less sodium. "Eat smaller portions," Hayes said.
"Potato chips, pretzels, and popcorn — which we think of as the saltiest foods in our diet — are only No. 10," said CDC Director Dr. Thomas Frieden.
Breads and rolls aren't really saltier than many of the other foods, but people tend to eat a lot of them, said Mary Cogswell, a CDC senior scientist who co-authored the report.
Salt is the main source of sodium for most people, and sodium increases the risk of high blood pressure, a major cause of heart disease and stroke. Health officials say most Americans get too much salt, mostly from processed and restaurant foods — not added from the salt shaker.
Experts have known that the sodium in breads and certain other foods can add up, but even CDC officials were amazed that just 10 foods are responsible for 44 percent of the sodium consumed.
"It's possible to eat a whole bunch of sodium without it seeming salty," noted John Hayes, an assistant professor of food science at Penn State, who was not involved in the report.
According to the CDC, breads and rolls account for about 7 percent of the salt that the average American eats in a day. Next on the list: cold cuts and cured meats; pizza; fresh and processed poultry; soups; fast-food hamburgers and sandwiches and cheese.
Rounding out the list — and accounting for about 3 percent each — are spaghetti and other pasta dishes; meatloaf and other meat dishes and snacks like potato gucci outlet chips and pretzels.
Dietary guidelines recommend no more than 2,300 milligrams of sodium a day, equal to about a teaspoon of salt. Certain people, such as those with high blood pressure, should eat even less. But average sodium consumption in the U.S. is around 3,300 milligrams, the CDC study found. Only 1 in 10 Americans meet the teaspoon guideline.
The amount of sodium in food types can vary. For example, a slice of white bread can have between 80 and 230 milligrams of sodium. A cup of canned chicken noodle soup has between 100 and 940 milligrams and 3 ounces of luncheon meat has between 450 and 1,050 milligrams. A small 1 ounce bag of potato chips ranges from 50 to 200 milligrams.
The new CDC report is based on surveys of more than 7,200 people in 2007 and 2008, including nearly 3,000 children. Participants were surveyed twice, each time answering detailed questions about what they had eaten over the previous day. Researchers then broke down what they ate into categories, and assigned sodium amounts.
Salt reduction has become a recent focus of public health campaigns, and some major food makers have taken steps or announced plans to gradually reduce sodium in their products.
CDC officials — who have long encouraged people to eat more fruits and vegetables — stopped short of advising people to lay off the bread. But they are encouraging consumers to read labels and, for example, buy brands of bread that have lower sodium.
"People can choose how much salt to add to their food at the table. They can't take it out once it's there," Frieden said.Gucci wallets, cheap gucci wallets 2012 outlet for men and women.
There's another way to consume less sodium. "Eat smaller portions," Hayes said.
2012年2月6日星期一
They found that male smokers exhibited faster mental decline
Smoking is known to be a risk factor for dementia in the aged, but the extent to which it is a risk factor for cognitive problems earlier in life is less-well understood, wrote the team.Gucci outlet online shop provides gucci 2012 new arrivals, up to 70% off. Welcome to buy cheap gucci items for men and women, all are latest styles in various colors for your choice.
Led by Severine Sabia of University College London's Department of Epidemiology and Public Health, the researchers looked at data collected from 5,099 men and 2,137 women. The subjects were employees of the British Civil Service who had participated in the Whitehall II study, which launched in 1985 and which conducted its ninth phase from 2007 to 2009.
To assess the relationship between subjects' smoking history and their level of cognitive decline, Sabia and her colleagues reviewed six self-reported assessments of smoking status collected over a period of 25 years, and three assessments of cognitive function collected over a period of 10 years. The cognitive tests were administered when participants were 44-69 years old, 50-74 years old and 55-80 years old.
They found that male smokers exhibited faster mental decline than non-smokers -- and the decline was more pronounced the more cigarettes a subject smoked.
"The effect size associated with smoking is similar to that associated with 10 years of age," they wrote.
Smokers who had quit at least 10 years before the first assessment did not show a significant speed-up in cognitive decline. Neither did women -- perhaps, the authors wrote, because the men in the study smoked more than the women did. They also hypothesized that it could be because smoking was associated with other risk factors in men, such as greater alcohol consumption.
The team wrote that it was not sure of the mechanism behind smokers' rapid mental decline, suggesting that it could stem from vascular or lung damage.
"It is increasingly recognized that age-related cognitive pathologies such as dementia result from long-term processes, perhaps beginning as long as 20 to 30 years before the clinical diagnosis of dementia. Our study illustrates the importance of examining risk factors for cognitive decline much earlier in the life course," the coauthors concluded.
This is according to scientists who have reconstructed the song of a cricket that chirped 165 million years ago.
A remarkably complete fossil of the prehistoric insect enabled the team to see the structures in its wings that rubbed together to make the sound.
The international team report their findings in the journal PNAS.
Scientists from the US and China discovered the cheapguccioutlet2012.com tiny fossil and named their newly discovered species Archaboilus musicus , because the music-making structures in its body were so clearly visible.
When insect expert Dr Fernando Montealegre Zapata, from the University of Bristol, found out that his colleagues had such a remarkable fossil, he was keen to see it.
"I was very surprised," he told BBC Nature, "because those [structures] are very very small - at the microscopic level."
Dr Zapata studies sound production and communication in living insects, working out how the musical instruments contained in many insects' bodies produce a particular sound, and exactly how that sound is made.
Just like modern bush crickets - also known as katydids - the Jurassic insects produced music with their wings. A "plectrum" on one wing was dragged along a microscopic comb-like structure on the other.
This produces a continuous "chirp" as the male insects rub, or "stridulate" their wings in a scissor-like motion. Dr Zapata described this stridulation as similar to playing a tiny violin.
By looking at the wing structures, he explained, "I could estimate that the animal made pure, musical tones".
Such a single-note tone would have transmitted efficiently - a regular wave of sound penetrating a noisy environment cluttered with vegetation. This would have allowed a female cricket to detect a male's song from tens of metres away.
Dr Zapata then set out to calculate the frequency of the tone, which denotes how high- or low-pitched it sounded. To to this, he simply compared the size and shape of its music-making or "stridulatory" instruments to those of living cricket species.
"I produced a graph of [living] species, plotting the measurements of their sound-making structures against the frequency of the sound they made," he explained.
"Using the measurements, I could plot this extinct species onto that graph."
He discovered that A. musicus used a relatively low-pitched song, compared with modern bush crickets.
This suggested that the Jurassic forest was a cluttered and "noisy environment - especially at night", he said.
"There were probably frogs, other [insects] and sounds from the water," he said.
Being noctural, A. musicus would not have had to hide its musical call from predators that were active during the day, including the famous Jurassic bird, Archaeopteryx.
The crickets may have been hunted by early mammals. But bats - many of which feast on nocturnal insects - did not appear until about 100 million years later.
"That's when the modern katydids became ultrasonic," said Dr Zapata.
The researcher emphasised how lucky he and his team were to find this extraordinary fossil.
"This animal allows us to build a picture of the ecology of the Jurassic forest," he said, "and will give hints as to how other animals were singing at the time."
Prof Mike Ritchie from the University of St Andrews said it was surprising that "way back in early cricket time, they were already producing these very musical calls".Gucci watches on sale, buy cheap gucci watches 2012, 70% off.
"People thought singing in crickets probably evolved later from a startle reflex," he told BBC Nature.
"But this suggests that [very early on] they were already... producing these lovely, pure tones to compete for a mate.
Led by Severine Sabia of University College London's Department of Epidemiology and Public Health, the researchers looked at data collected from 5,099 men and 2,137 women. The subjects were employees of the British Civil Service who had participated in the Whitehall II study, which launched in 1985 and which conducted its ninth phase from 2007 to 2009.
To assess the relationship between subjects' smoking history and their level of cognitive decline, Sabia and her colleagues reviewed six self-reported assessments of smoking status collected over a period of 25 years, and three assessments of cognitive function collected over a period of 10 years. The cognitive tests were administered when participants were 44-69 years old, 50-74 years old and 55-80 years old.
They found that male smokers exhibited faster mental decline than non-smokers -- and the decline was more pronounced the more cigarettes a subject smoked.
"The effect size associated with smoking is similar to that associated with 10 years of age," they wrote.
Smokers who had quit at least 10 years before the first assessment did not show a significant speed-up in cognitive decline. Neither did women -- perhaps, the authors wrote, because the men in the study smoked more than the women did. They also hypothesized that it could be because smoking was associated with other risk factors in men, such as greater alcohol consumption.
The team wrote that it was not sure of the mechanism behind smokers' rapid mental decline, suggesting that it could stem from vascular or lung damage.
"It is increasingly recognized that age-related cognitive pathologies such as dementia result from long-term processes, perhaps beginning as long as 20 to 30 years before the clinical diagnosis of dementia. Our study illustrates the importance of examining risk factors for cognitive decline much earlier in the life course," the coauthors concluded.
This is according to scientists who have reconstructed the song of a cricket that chirped 165 million years ago.
A remarkably complete fossil of the prehistoric insect enabled the team to see the structures in its wings that rubbed together to make the sound.
The international team report their findings in the journal PNAS.
Scientists from the US and China discovered the cheapguccioutlet2012.com tiny fossil and named their newly discovered species Archaboilus musicus , because the music-making structures in its body were so clearly visible.
When insect expert Dr Fernando Montealegre Zapata, from the University of Bristol, found out that his colleagues had such a remarkable fossil, he was keen to see it.
"I was very surprised," he told BBC Nature, "because those [structures] are very very small - at the microscopic level."
Dr Zapata studies sound production and communication in living insects, working out how the musical instruments contained in many insects' bodies produce a particular sound, and exactly how that sound is made.
Just like modern bush crickets - also known as katydids - the Jurassic insects produced music with their wings. A "plectrum" on one wing was dragged along a microscopic comb-like structure on the other.
This produces a continuous "chirp" as the male insects rub, or "stridulate" their wings in a scissor-like motion. Dr Zapata described this stridulation as similar to playing a tiny violin.
By looking at the wing structures, he explained, "I could estimate that the animal made pure, musical tones".
Such a single-note tone would have transmitted efficiently - a regular wave of sound penetrating a noisy environment cluttered with vegetation. This would have allowed a female cricket to detect a male's song from tens of metres away.
Dr Zapata then set out to calculate the frequency of the tone, which denotes how high- or low-pitched it sounded. To to this, he simply compared the size and shape of its music-making or "stridulatory" instruments to those of living cricket species.
"I produced a graph of [living] species, plotting the measurements of their sound-making structures against the frequency of the sound they made," he explained.
"Using the measurements, I could plot this extinct species onto that graph."
He discovered that A. musicus used a relatively low-pitched song, compared with modern bush crickets.
This suggested that the Jurassic forest was a cluttered and "noisy environment - especially at night", he said.
"There were probably frogs, other [insects] and sounds from the water," he said.
Being noctural, A. musicus would not have had to hide its musical call from predators that were active during the day, including the famous Jurassic bird, Archaeopteryx.
The crickets may have been hunted by early mammals. But bats - many of which feast on nocturnal insects - did not appear until about 100 million years later.
"That's when the modern katydids became ultrasonic," said Dr Zapata.
The researcher emphasised how lucky he and his team were to find this extraordinary fossil.
"This animal allows us to build a picture of the ecology of the Jurassic forest," he said, "and will give hints as to how other animals were singing at the time."
Prof Mike Ritchie from the University of St Andrews said it was surprising that "way back in early cricket time, they were already producing these very musical calls".Gucci watches on sale, buy cheap gucci watches 2012, 70% off.
"People thought singing in crickets probably evolved later from a startle reflex," he told BBC Nature.
"But this suggests that [very early on] they were already... producing these lovely, pure tones to compete for a mate.
2012年2月5日星期日
Facebook declined to comment in advance of its offering
Amid the jaw-dropping financial figures the company revealed last week when it filed for a public offering was an interesting admission. Although more than cheap burberry outlet 2012 half of its 845 million members log into Facebook on a mobile device, the company has not yet found a way to make real money from that use.
“We do not currently directly generate any meaningful revenue from the use of Facebook mobile products, and our ability to do so successfully is unproven,” the company said in its review of the risks it faces.
In a world that is rapidly moving toward an era of mobile computing, this is a troubling issue for Silicon Valley’s brightest star — particularly since much of Facebook’s growth right now is in countries like Chile, Turkey, Venezuela and Brazil, where people largely have access to the Internet using cellphones.
Facebook is not the only company struggling to translate the success of its Web site to mobile devices, where screen space is at a premium and people have little patience for clutter or slow loading times. It is a problem that plagues companies as diverse as news publishers and the streaming radio service Pandora, and it is likely to loom larger. There were more global shipments of smartphones than of personal computers in 2011, according to a recent report from Canalys, a research firm.
But the issue seems particularly urgent in the case of Facebook, which is wildly popular among its users and is seen as a company of the future, a hybrid of social hub and information conduit, platform and publisher. In other words, if Facebook cannot figure it out, who can?
“It’s a huge Achilles’ heel for them,” said Susan Etlinger, a consultant at the Altimeter Group who advises companies on how to use technology. “There’s clearly a movement toward more social media consumption on mobile devices, and Facebook doesn’t have a revenue strategy for that shift. They haven’t figured it out yet.”
Facebook declined to comment in advance of its offering, but the company outlined its concerns in the filing, stating that it expected its mobile users to “exceed the growth rate of our overall monthly active users for the foreseeable future.” And if executives are not able to chart a path to profitability on mobile platforms, the filing indicated, the company’s “revenue and financial results may be negatively affected.”
At stake, experts say, is a large chunk of advertising revenue. Facebook brings in most of its revenue by selling space on its Web site to advertisers who want to reach its users. Overall spending on mobile advertising in the United States is expected to reach $2.6 billion this year, up 80 percent from $1.45 billion in 2011, according to research by eMarketer. But that will still be just a sliver of what is likely to be a $39.5 billion online advertising market.
Google, a Facebook competitor on the Web, was the biggest player in the mobile ad market last year with about $750 million in revenue, and Apple came in second with more than $90 million, eMarketer says.Burberry watches, designer burberry watch cheap outlet 2012.
“It’s still immature when compared to online, print and TV advertising,” said Noah Elkin, an analyst with eMarketer. “But it’s growing at a faster pace, even though its revenues are still dwarfed by the other formats.”
One big problem with mobile ads is that users are less receptive to intrusive advertisements when they are focused on a goal like quickly posting a status update or finding an address. People using the Web on a computer tend to click on online ads up to eight times as often as those on mobile devices, Mr. Elkin said.
“We’ve had ads on our desktops for 15 years and we’re used to them,” he said. “But on the smaller smartphone screen, they’re distracting and viewers tend to notice them more even though there are usually fewer ads.”
It is still relatively early in the evolution of mobile marketing, of course, and it is possible Facebook is deliberately holding back in this area. Analysts say the company may be focusing on building traffic to its mobile Web site and applications first — much as it originally kept its regular Web site free of ads to avoid alienating new users.
But Facebook may also be sitting on an untapped reservoir of advertising revenue, experts say. Its mobile ads could be highly lucrative should the company start showing users advertisements or coupons pegged to the places they visit and the businesses they frequent.
Facebook has begun to creep into that territory with Places, a service that allows users to “check in” and share their whereabouts with friends. That, and other location services, could eventually lay the groundwork for attracting local and small-business advertisers.
“Even though Facebook’s browser advertising is already very targeted compared to other services, mobile advertising could be even more so, because it could take location into account as well," said Jan Dawson, the chief telecommunications analyst at the research firm Ovum.
After ads, Facebook’s second-biggest source of revenue is payments from partners like Zynga that have games and other apps running on its site. When those app makers sell things like virtual goods through Facebook’s payment system, Facebook takes a cut — and in the case of Zynga, that cut generated 12 percent of Facebook’s revenue last year. But on iPhones and iPads, Facebook has to contend with Apple, which takes its own share of app makers’ revenue from such sales.
If Facebook were to bring Zynga’s games to its iPhone and iPad apps, for example, it would have to share that revenue with Apple, which requires app makers to hand over 30 percent of their proceeds.
Google puts no such restrictions on apps for devices running its Android software, but given the increasing rivalry between Facebook and Google in social networking, Facebook is not in full control of its destiny there either.
“The question is about who will be in the driver’s seat,” said Sandeep Dahiya, an associate professor of finance at Georgetown University who specializes moncler jackets cheap in corporate finance and public offerings. “Can Facebook monetize applications and game play on top of Apple and Google?”
Given how crucial mobile activity is for Facebook’s future, it came as a surprise to many that the company seemed to drag its feet in releasing an application for the iPad, as it finally did in October. Some criticize the company’s iPhone app for being sluggish and plagued with bugs.
That has led some to question whether Facebook has deliberately let its mobile applications languish while it settles on a broader strategy. If users come to Facebook through a mobile Web browser rather than through an app, the company can avoid the Apple toll booth.
“It’s the art of war,” said Shervin Pishevar, a serial entrepreneur who now advises and invests in social start-ups at Menlo Partners, a venture capital firm in Silicon Valley. “If the app is making users insane, they are just going to go to the browser version of the site. Which is a big win for Facebook because it gives them an advantage over Apple.”
Steering users to mobile-friendly Web pages also lets Facebook avoid making an app for every type of phone, said Joe Hewitt, who created the first iPhone app for Facebook and left the company last year.
“It’s always to Facebook’s advantage to have the Web be their operating system and leverage that to their advantage,” he said. “You can develop on the Web and reuse as much of the code as you can.”
In its filing, Facebook did say it planned to explore and experiment with mobile advertising, including inserting so-called sponsored stories into the stream of updates. These are messages involving a user’s friends that an advertiser can choose to highlight and amplify — as in “Bob Smith likes Gatorade.”
Facebook is also setting up an event later moncler jackets this month for Facebook advertisers, the first of its kind, which is to feature presentations from several top executives including Sheryl Sandberg, the chief operating officer.
“We do not currently directly generate any meaningful revenue from the use of Facebook mobile products, and our ability to do so successfully is unproven,” the company said in its review of the risks it faces.
In a world that is rapidly moving toward an era of mobile computing, this is a troubling issue for Silicon Valley’s brightest star — particularly since much of Facebook’s growth right now is in countries like Chile, Turkey, Venezuela and Brazil, where people largely have access to the Internet using cellphones.
Facebook is not the only company struggling to translate the success of its Web site to mobile devices, where screen space is at a premium and people have little patience for clutter or slow loading times. It is a problem that plagues companies as diverse as news publishers and the streaming radio service Pandora, and it is likely to loom larger. There were more global shipments of smartphones than of personal computers in 2011, according to a recent report from Canalys, a research firm.
But the issue seems particularly urgent in the case of Facebook, which is wildly popular among its users and is seen as a company of the future, a hybrid of social hub and information conduit, platform and publisher. In other words, if Facebook cannot figure it out, who can?
“It’s a huge Achilles’ heel for them,” said Susan Etlinger, a consultant at the Altimeter Group who advises companies on how to use technology. “There’s clearly a movement toward more social media consumption on mobile devices, and Facebook doesn’t have a revenue strategy for that shift. They haven’t figured it out yet.”
Facebook declined to comment in advance of its offering, but the company outlined its concerns in the filing, stating that it expected its mobile users to “exceed the growth rate of our overall monthly active users for the foreseeable future.” And if executives are not able to chart a path to profitability on mobile platforms, the filing indicated, the company’s “revenue and financial results may be negatively affected.”
At stake, experts say, is a large chunk of advertising revenue. Facebook brings in most of its revenue by selling space on its Web site to advertisers who want to reach its users. Overall spending on mobile advertising in the United States is expected to reach $2.6 billion this year, up 80 percent from $1.45 billion in 2011, according to research by eMarketer. But that will still be just a sliver of what is likely to be a $39.5 billion online advertising market.
Google, a Facebook competitor on the Web, was the biggest player in the mobile ad market last year with about $750 million in revenue, and Apple came in second with more than $90 million, eMarketer says.Burberry watches, designer burberry watch cheap outlet 2012.
“It’s still immature when compared to online, print and TV advertising,” said Noah Elkin, an analyst with eMarketer. “But it’s growing at a faster pace, even though its revenues are still dwarfed by the other formats.”
One big problem with mobile ads is that users are less receptive to intrusive advertisements when they are focused on a goal like quickly posting a status update or finding an address. People using the Web on a computer tend to click on online ads up to eight times as often as those on mobile devices, Mr. Elkin said.
“We’ve had ads on our desktops for 15 years and we’re used to them,” he said. “But on the smaller smartphone screen, they’re distracting and viewers tend to notice them more even though there are usually fewer ads.”
It is still relatively early in the evolution of mobile marketing, of course, and it is possible Facebook is deliberately holding back in this area. Analysts say the company may be focusing on building traffic to its mobile Web site and applications first — much as it originally kept its regular Web site free of ads to avoid alienating new users.
But Facebook may also be sitting on an untapped reservoir of advertising revenue, experts say. Its mobile ads could be highly lucrative should the company start showing users advertisements or coupons pegged to the places they visit and the businesses they frequent.
Facebook has begun to creep into that territory with Places, a service that allows users to “check in” and share their whereabouts with friends. That, and other location services, could eventually lay the groundwork for attracting local and small-business advertisers.
“Even though Facebook’s browser advertising is already very targeted compared to other services, mobile advertising could be even more so, because it could take location into account as well," said Jan Dawson, the chief telecommunications analyst at the research firm Ovum.
After ads, Facebook’s second-biggest source of revenue is payments from partners like Zynga that have games and other apps running on its site. When those app makers sell things like virtual goods through Facebook’s payment system, Facebook takes a cut — and in the case of Zynga, that cut generated 12 percent of Facebook’s revenue last year. But on iPhones and iPads, Facebook has to contend with Apple, which takes its own share of app makers’ revenue from such sales.
If Facebook were to bring Zynga’s games to its iPhone and iPad apps, for example, it would have to share that revenue with Apple, which requires app makers to hand over 30 percent of their proceeds.
Google puts no such restrictions on apps for devices running its Android software, but given the increasing rivalry between Facebook and Google in social networking, Facebook is not in full control of its destiny there either.
“The question is about who will be in the driver’s seat,” said Sandeep Dahiya, an associate professor of finance at Georgetown University who specializes moncler jackets cheap in corporate finance and public offerings. “Can Facebook monetize applications and game play on top of Apple and Google?”
Given how crucial mobile activity is for Facebook’s future, it came as a surprise to many that the company seemed to drag its feet in releasing an application for the iPad, as it finally did in October. Some criticize the company’s iPhone app for being sluggish and plagued with bugs.
That has led some to question whether Facebook has deliberately let its mobile applications languish while it settles on a broader strategy. If users come to Facebook through a mobile Web browser rather than through an app, the company can avoid the Apple toll booth.
“It’s the art of war,” said Shervin Pishevar, a serial entrepreneur who now advises and invests in social start-ups at Menlo Partners, a venture capital firm in Silicon Valley. “If the app is making users insane, they are just going to go to the browser version of the site. Which is a big win for Facebook because it gives them an advantage over Apple.”
Steering users to mobile-friendly Web pages also lets Facebook avoid making an app for every type of phone, said Joe Hewitt, who created the first iPhone app for Facebook and left the company last year.
“It’s always to Facebook’s advantage to have the Web be their operating system and leverage that to their advantage,” he said. “You can develop on the Web and reuse as much of the code as you can.”
In its filing, Facebook did say it planned to explore and experiment with mobile advertising, including inserting so-called sponsored stories into the stream of updates. These are messages involving a user’s friends that an advertiser can choose to highlight and amplify — as in “Bob Smith likes Gatorade.”
Facebook is also setting up an event later moncler jackets this month for Facebook advertisers, the first of its kind, which is to feature presentations from several top executives including Sheryl Sandberg, the chief operating officer.
2012年2月2日星期四
Location alone does not make for a habitable planet
The planet has 4.5 times Earth's mass and orbits in the heart of its star's habitable zone – the region where water could remain stable on an orbiting planet's surface. Liquid water is a necessary ingredient for organic life.Cheap burberry - designer bags, shoes, accessories, clothing outlet 2012.
For now, however, too little is known about the planet's composition and the makeup of any atmosphere – if it has one – to say with confidence that water is likely to be there, researchers say. Location alone does not make for a habitable planet. Some scientists suggest that the newfound planet could be caught with one hemisphere permanently facing its star, lessening any prospects for life.
Still, the researchers note the planet's position well within the habitable zone is an encouraging first sign.
This is not the first so-called super Earth astronomers have detected in a star's habitable zone. In December, scientists with NASA's Kepler mission announced the discovery of a super Earth orbiting within its host star's habitable zone. That planet was orbiting a sun-like star, marking an important step along the path toward meeting the mission's goal of uncovering Earth-size planets orbiting within the habitable zone of sun-like stars.
But the new planet, GJ 667Cc, orbits a red dwarf – a type of star that is much smaller, fainter, and far more common in the galaxy than sun-like stars. Given red dwarfs' prevalence, the finding suggests that the galaxy should be brimming with super Earths in habitable zones, the research team says.
The new planet's host star, GJ 667C, has about 30 percent of the sun's mass and gives off most of its radiation as infrared light. It's part of a triple-star system that also contains a pair of orange-dwarf stars. These don't come closer to GJ 667C than about 230 astronomical units, or 230 times the distance between Earth and the sun. They would be distant specks in the sky to a spacecraft orbiting the new planet.
Because the star is substantially fainter than the sun, its habitable zone is closer. GJ 677Cc orbits its red dwarf at about 0.12 astronomical units, zipping around the star once every 27.15 days.Burberry ties, silk ties for men, cheap burberry tie on sale.
Astrobiologists suggest red dwarfs have an important thing going for them as energy sources for life on any planets orbiting them: longevity.
Red dwarfs are dim because they are not burning their hydrogen fuel as furiously as more-massive stars. And unlike more massive stars, they have access to all of their hydrogen fuel. So they last longer than sun-like stars.
The sun boasts a respectable 10-billion year life span. For a star like GJ 677C, a life span is measured in trillions of years – plenty of time for life to emerge and evolve many times over if conditions permit. The team estimates that GJ 667C is only about 5 billion years old.
Half baked, half frozen world?
Yet others caution that the laws of physics may conspire against the presence of liquid water on planets in an orbit like GJ 667Cc's.
The planet may be close enough to the star that, if the planet's orbit is circular, the gravitational interaction between the two objects eventually will force the planet slow its rotation until it presents the same hemisphere to the star all the time, says University of Maine astronomer Neil Comins.
Astronomers call this synchronous rotation: The planet's rotation rate matches the time it takes the planet to orbits its star. One hemisphere of the planet is permanently roasting, the other is frozen.
Even with an atmosphere that circulates between the day side and night side, it's unclear if enough warmth will make it to the night side to keep water vapor transported there from freezing out as snow, rarely if ever to return to the day side. In effect, the night side could rob the day side of any water.
Achieving synchronous rotation likely would happen within a billion years or so for an Earth-size planet, Dr. Comins says, especially if it has a moon, which also acts to slow the planet's rotation.
For a super Earth, however, there might be hope. If the planet has no moon and is dense enough, the spin-down could take longer, allowing warmth to circulate and water to accumulate for a while longer before the big freeze and fry.
If a planet is in a elliptical orbit, which often is the case, the prospects are somewhat brighter, Comins suggests. The elliptical orbit would allow the planet to rotate moncler jackets 2011 and expose more of itself to light from its sun. Potentially habitable areas would fall in the twilight zone between hemispheres.
Some research suggests that the presence of the right kind of atmosphere could redistribute heat more readily than previously thought, “so it doesn't look that bad,” says Guillem Anglada-Escudé, a researcher at the University of Gottingen in Germany who led the international team.
Yet all of this remains speculation, he adds, until more is known about the planet.
How they found it
The discovery of GJ 667Cc emerged from a test Dr. Anglada-Escudé was making of new software, which was designed to analyze archived data to hunt for extrasolar planets. The team's planet-hunting approach measures the wobble that gravity from an orbiting planet imparts on its star.
The wobble shows up as back-and-forth shifts in the star's spectrum – a kind of bar code bearing information on the chemical elements present in the star's atmosphere. As the planet slips behind the star, the entire spectrum shifts toward red. When the planet tugs the star toward the observer, the star's spectrum shifts toward blue.
In 2009, researchers announced the discovery of a planet orbiting GJ 667C, with an orbital period of about 7 days. Last year, another team suggested a planet was orbiting with a 28-day period. But neither group provided any data or detailed analysis to back the claims. So Anglada-Escudé's team picked the system as the test dummy for its new detection software.
Not only did his team provide the first solid evidence of GJ 677Cb, a planet with 5.2 times Earth's mass orbiting the star every 7.2 days. It also found the super Earth in the habitable zone, as well as evidence for perhaps as many as two additional, more-distant planets.
The technique the team used, formally known as radial-velocity measurements, can provide only part of the picture, however. The team notes that there is a small chance that the orientation of the GJ 677C system could be just right, allowing scientists to watch the planets pass in front of their host star, an event called a transit.
The star is bright enough and close enough that even amateur-class telescopes could detect any transits, Anglada-Escudé says. Such measurements would allow astronomers to determine more precisely the shape of the planets' orbits, and importantly, the planet's densities. The density estimates would allow a first cut at estimating what the planets are made of and what is in their atmospheres, if they have any.
Within two or three years, he adds, “we may moncler jackets have the capability of looking at the spectral features of the atmospheres of these planets, if they really transit.”
Accomplishing that “would be a real breakthrough,” he says.
For now, however, too little is known about the planet's composition and the makeup of any atmosphere – if it has one – to say with confidence that water is likely to be there, researchers say. Location alone does not make for a habitable planet. Some scientists suggest that the newfound planet could be caught with one hemisphere permanently facing its star, lessening any prospects for life.
Still, the researchers note the planet's position well within the habitable zone is an encouraging first sign.
This is not the first so-called super Earth astronomers have detected in a star's habitable zone. In December, scientists with NASA's Kepler mission announced the discovery of a super Earth orbiting within its host star's habitable zone. That planet was orbiting a sun-like star, marking an important step along the path toward meeting the mission's goal of uncovering Earth-size planets orbiting within the habitable zone of sun-like stars.
But the new planet, GJ 667Cc, orbits a red dwarf – a type of star that is much smaller, fainter, and far more common in the galaxy than sun-like stars. Given red dwarfs' prevalence, the finding suggests that the galaxy should be brimming with super Earths in habitable zones, the research team says.
The new planet's host star, GJ 667C, has about 30 percent of the sun's mass and gives off most of its radiation as infrared light. It's part of a triple-star system that also contains a pair of orange-dwarf stars. These don't come closer to GJ 667C than about 230 astronomical units, or 230 times the distance between Earth and the sun. They would be distant specks in the sky to a spacecraft orbiting the new planet.
Because the star is substantially fainter than the sun, its habitable zone is closer. GJ 677Cc orbits its red dwarf at about 0.12 astronomical units, zipping around the star once every 27.15 days.Burberry ties, silk ties for men, cheap burberry tie on sale.
Astrobiologists suggest red dwarfs have an important thing going for them as energy sources for life on any planets orbiting them: longevity.
Red dwarfs are dim because they are not burning their hydrogen fuel as furiously as more-massive stars. And unlike more massive stars, they have access to all of their hydrogen fuel. So they last longer than sun-like stars.
The sun boasts a respectable 10-billion year life span. For a star like GJ 677C, a life span is measured in trillions of years – plenty of time for life to emerge and evolve many times over if conditions permit. The team estimates that GJ 667C is only about 5 billion years old.
Half baked, half frozen world?
Yet others caution that the laws of physics may conspire against the presence of liquid water on planets in an orbit like GJ 667Cc's.
The planet may be close enough to the star that, if the planet's orbit is circular, the gravitational interaction between the two objects eventually will force the planet slow its rotation until it presents the same hemisphere to the star all the time, says University of Maine astronomer Neil Comins.
Astronomers call this synchronous rotation: The planet's rotation rate matches the time it takes the planet to orbits its star. One hemisphere of the planet is permanently roasting, the other is frozen.
Even with an atmosphere that circulates between the day side and night side, it's unclear if enough warmth will make it to the night side to keep water vapor transported there from freezing out as snow, rarely if ever to return to the day side. In effect, the night side could rob the day side of any water.
Achieving synchronous rotation likely would happen within a billion years or so for an Earth-size planet, Dr. Comins says, especially if it has a moon, which also acts to slow the planet's rotation.
For a super Earth, however, there might be hope. If the planet has no moon and is dense enough, the spin-down could take longer, allowing warmth to circulate and water to accumulate for a while longer before the big freeze and fry.
If a planet is in a elliptical orbit, which often is the case, the prospects are somewhat brighter, Comins suggests. The elliptical orbit would allow the planet to rotate moncler jackets 2011 and expose more of itself to light from its sun. Potentially habitable areas would fall in the twilight zone between hemispheres.
Some research suggests that the presence of the right kind of atmosphere could redistribute heat more readily than previously thought, “so it doesn't look that bad,” says Guillem Anglada-Escudé, a researcher at the University of Gottingen in Germany who led the international team.
Yet all of this remains speculation, he adds, until more is known about the planet.
How they found it
The discovery of GJ 667Cc emerged from a test Dr. Anglada-Escudé was making of new software, which was designed to analyze archived data to hunt for extrasolar planets. The team's planet-hunting approach measures the wobble that gravity from an orbiting planet imparts on its star.
The wobble shows up as back-and-forth shifts in the star's spectrum – a kind of bar code bearing information on the chemical elements present in the star's atmosphere. As the planet slips behind the star, the entire spectrum shifts toward red. When the planet tugs the star toward the observer, the star's spectrum shifts toward blue.
In 2009, researchers announced the discovery of a planet orbiting GJ 667C, with an orbital period of about 7 days. Last year, another team suggested a planet was orbiting with a 28-day period. But neither group provided any data or detailed analysis to back the claims. So Anglada-Escudé's team picked the system as the test dummy for its new detection software.
Not only did his team provide the first solid evidence of GJ 677Cb, a planet with 5.2 times Earth's mass orbiting the star every 7.2 days. It also found the super Earth in the habitable zone, as well as evidence for perhaps as many as two additional, more-distant planets.
The technique the team used, formally known as radial-velocity measurements, can provide only part of the picture, however. The team notes that there is a small chance that the orientation of the GJ 677C system could be just right, allowing scientists to watch the planets pass in front of their host star, an event called a transit.
The star is bright enough and close enough that even amateur-class telescopes could detect any transits, Anglada-Escudé says. Such measurements would allow astronomers to determine more precisely the shape of the planets' orbits, and importantly, the planet's densities. The density estimates would allow a first cut at estimating what the planets are made of and what is in their atmospheres, if they have any.
Within two or three years, he adds, “we may moncler jackets have the capability of looking at the spectral features of the atmospheres of these planets, if they really transit.”
Accomplishing that “would be a real breakthrough,” he says.
2012年2月1日星期三
Given their need to access rock-bound minerals
The study reveals that the first land plants triggered a series of ice ages by removing minerals, like calcium, magnesium cheap burberry outlet 2012 and others, from rocks in order to live.
“Given their need to access rock-bound minerals, we suggest that these first colonizers actually caused a substantial change in chemical weathering, with a significant impact on the global carbon cycle and climate,” the researchers write in the study.
According to the study, the “chemical weathering” caused by the land plants’ need to grow eliminated carbon dioxide from the atmosphere and lowered global temperatures by approximately 5 degrees Celsius.
Tim Lenton, one of the study’s lead researchers and a professor at the University of Exeter, posited that it is highly unlikely that plants will ever be able to trigger a series of ice ages again.Burberry watches, designer burberry watch cheap outlet 2012.
The researchers combined Physcomitrella patens (moss) and rocks in incubators to recreate the “chemical weathering” effect the first land plants had on the ancient rocks. After three months, the researchers deployed an Earth system model to determine how the plants could have impacted the Earth’s climate millions of years ago.
“This study demonstrates the powerful effects that plants have on our climate. Although plants are still cooling the Earth’s climate by reducing atmospheric carbon levels, they cannot keep up with the speed of today’s human-induced climate change. In fact, it would take millions of years for plants to remove current carbon emissions from the atmosphere,” Mr. Lenton said, according to the John Innes Centre.
Liam Dolan, another one of the study’s lead researchers and a professor at Oxford University, talked about the study’s importance to those concerned about climate change and other environmental issues.
“For me the most important take-home moncler jackets cheap message is that the invasion of the land by plants – a pivotal time in the history of the planet – brought about huge climate changes. Our discovery emphasises that plants have a central regulatory role in the control of climate: they did yesterday, they do today and they certainly will in the future,” Mr. Dolan posited.
The study was led by a team with members from multiple universities, including Exeter, Oxford and East Anglia. The John Innes Centre also contributed to the study. The Earth and Life Systems Alliance, which moncler jackets is a collaboration between the John Innes Centre and the University of East Anglia, funded the study.
“Given their need to access rock-bound minerals, we suggest that these first colonizers actually caused a substantial change in chemical weathering, with a significant impact on the global carbon cycle and climate,” the researchers write in the study.
According to the study, the “chemical weathering” caused by the land plants’ need to grow eliminated carbon dioxide from the atmosphere and lowered global temperatures by approximately 5 degrees Celsius.
Tim Lenton, one of the study’s lead researchers and a professor at the University of Exeter, posited that it is highly unlikely that plants will ever be able to trigger a series of ice ages again.Burberry watches, designer burberry watch cheap outlet 2012.
The researchers combined Physcomitrella patens (moss) and rocks in incubators to recreate the “chemical weathering” effect the first land plants had on the ancient rocks. After three months, the researchers deployed an Earth system model to determine how the plants could have impacted the Earth’s climate millions of years ago.
“This study demonstrates the powerful effects that plants have on our climate. Although plants are still cooling the Earth’s climate by reducing atmospheric carbon levels, they cannot keep up with the speed of today’s human-induced climate change. In fact, it would take millions of years for plants to remove current carbon emissions from the atmosphere,” Mr. Lenton said, according to the John Innes Centre.
Liam Dolan, another one of the study’s lead researchers and a professor at Oxford University, talked about the study’s importance to those concerned about climate change and other environmental issues.
“For me the most important take-home moncler jackets cheap message is that the invasion of the land by plants – a pivotal time in the history of the planet – brought about huge climate changes. Our discovery emphasises that plants have a central regulatory role in the control of climate: they did yesterday, they do today and they certainly will in the future,” Mr. Dolan posited.
The study was led by a team with members from multiple universities, including Exeter, Oxford and East Anglia. The John Innes Centre also contributed to the study. The Earth and Life Systems Alliance, which moncler jackets is a collaboration between the John Innes Centre and the University of East Anglia, funded the study.
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