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You can think of NASA's Discovery program as a sort of outer-space American Idol: every few years the agency invites scientists to propose unmanned planetary missions. The projects have to address some sort of fundamental science question, and (this is the tough part) they have to be relatively cheap to pull off — say, half a billion dollars or so. Then the proposals go through a grueling competition before judges who aren't as nasty as Simon Cowell but who are every bit as tough. The one left standing at the end gets the equivalent of a recording contract: NASA supplies the funding and the launch vehicle, and away the winner goes — to orbit Mercury, as the Messenger spacecraft is doing right now; or to rendezvous with a couple of asteroids, as the Dawn mission will start doing this July; or to smash into a comet on purpose, a feat achieved by Deep Impact in 2005, a mission not to be confused with the movie of the same name. Now it's time for the next contenders. NASA has just announced that the first round of the latest Discovery competition is over, with three entries out of 28 moving on to the finals. They are, in increasing distance from Earth: the Geophysical Monitoring Station (GEMS) lander, which would use seismometers to study the interior of Mars; the Comet Hopper, which would do just that, leaping from place to place across the surface of Comet 46P/Wirtanen to see how different parts of the tumbling body react to heating by the sun; and the Titan Mare Explorer (TiME), which would plop into a sea of liquid hydrocarbons on Saturn's moon Titan — the first oceangoing vessel ever to set sail on another world. If you had to come up with a theme that ties all three missions together, it would be "origins." The Titan explorer, for example, will be studying a place that — in a crude way, at least — resembles the early planet Earth at a time when life arose here. Titan, with a thick atmosphere and a bizarro-world form of weather featuring toxic winds and hydrocarbon rain, is home to a mix of complex chemistry, complete with organic molecules. The oceans provide a medium in which the molecules can move around and interact with each other. It's even conceivable, though clearly a long shot, that some form of microscopic life already exists on this frigid moon. The Mars lander, by contrast, would visit a place where the seas — plain water in this case — vanished long ago. But the mission of GEMS goes far deeper than that. By analyzing Marsquakes on the Red Planet, GEMS will try to get a handle on what the interior of Mars is like. Scientists don't currently know whether the planet's core is liquid, like Earth's, or solid, or some mushy consistency in between. It all depends on how efficiently Mars has cooled since it formed 4.5 billion years ago, and that depends in turn on the planet's internal structure. "That's the mission," says Bruce Banerdt, of NASA's Jet Propulsion Laboratory, the lead scientist for GEMS. "We want to understand how Mars was built." Along with sensitive seismographic equipment, GEMS will drill down about 20 ft. (6 m) with a thermometer-equipped probe, trying to figure out how quickly the temperature rises with depth. "That will let us extrapolate all the way down to the center," Banerdt says, "which will tell us how fast Mars is cooling."

WASHINGTON, April 25 (Xinhua) -- Study by scientists at the Rockefeller University shows that anti-inflammatory drugs reduce the effectiveness of the most widely used class of antidepressant medications, the selective serotonin reuptake inhibitors (SSRIs), taken for depression and obsessive-compulsive disorder and anxiety disorders.This discovery, published online Monday in the Proceedings of the National Academy of Sciences, may explain why so many depressed patients taking SSRIs do not respond to antidepressant treatment and suggests that this lack of effectiveness may be preventable.The study may be especially significant in the case of Alzheimer's disease. Such patients commonly suffer from depression and unless this can be treated successfully, the course of the illness is likely to be more severe. Depression in the elderly is also a risk factor for developing Alzheimer's Disease and researchers have suggested that treating depression in the elderly might reduce the risk of developing the disease.In the recent study, investigators treated mice with antidepressants in the presence or absence of anti-inflammatory drugs. They then examined how the mice behaved in tasks that are sensitive to antidepressant treatment. They found that the mice's behavioral responses to antidepressants were inhibited by anti- inflammatory/analgesic treatments.They then confirmed these effects in a human population. Depressed individuals who reported anti-inflammatory drug use were much less likely to have their symptoms relieved by an antidepressant than depressed patients who reported no anti- inflammatory drug use. The effect was rather dramatic since, in the absence of any anti-inflammatory or analgesic use, 54 percent of patients responded to the antidepressant, whereas success rates dropped to approximately 40 percent for those who reported using anti-inflammatory agents."Many elderly individuals suffering from depression also have arthritic or related diseases and as a consequence are taking both antidepressant and anti-inflammatory medications. Our results suggest that physicians should carefully balance the advantages and disadvantages of continuing anti-inflammatory therapy in patients being treated with antidepressant medications," leader author Paul Greengard said.

ABU DHABI, Feb. 10 (Xinhua) -- China is willing to deepen friendship, broaden cooperation, and enhance coordination with the United Arab Emirates (UAE) in international and regional affairs, visiting Chinese Foreign Minister Yang Jiechi said Thursday.During a meeting with Abu Dhabi Crown Prince Sheikh Mohammed bin Zayed Al Nahyan, Yang said China and the UAE have witnessed in recent years rapid development in their bilateral ties, with closer high-level contacts, increasingly strengthened mutual political trust, fruitful cooperation in such areas as trade and economy, and broadened cultural exchanges.China has praised the UAE's support in Xinjiang-related and human rights issues, he added.For his part, Sheikh Mohammed said the UAE-China relations are currently at an important period of in-depth development and faced with good opportunities.The UAE attaches great importance to its relations with China and hopes to cement the traditional friendship between the two countries and develop pragmatic cooperation in various fields, he added.Sheikh Mohammed said the UAE expects that China will continue to play a positive role in international and regional affairs.Earlier in the day, Yang also met with his UAE counterpart Sheikh Abdullah bin Zayed Al Nahyan. Both sides reached broad consensus after exchanging views on bilateral ties and regional issues of common concern.The Chinese foreign minister arrived in the UAE capital of Abu Dhabi late Wednesday for an official visit to the Gulf nation.

NEW YORK, May 27 (Xinhua) -- U.S. stocks expanded gains on Friday ahead of the long Memorial Day weekend as surging commodity prices overcame disappointing economic data.European Central Bank Governing Council member George Provopoulos said that Greece might deal with its debt problem if it sticks to the aid program. That comment, which was considered as bullish by investors, drove the U.S. dollar weaker and led commodity prices surge on Friday.The stock market was driven by higher commodities prices, with thin trading volume ahead of the Memorial Day holiday, despite somewhat disappointing economic data on Friday.The Commerce Department said that both personal income and spending rose 0.4 percent in April, in line with market estimates. However, the rise in spending was the smallest in three months, suggesting the consumption situation was still weak.Meanwhile, pending home sales dropped 11.6 percent in April. The reading was a seven-month low. The market expectation was a drop of 1 percent.Moreover, the Thomson Reuters/University of Michigan Consumer Sentiment index came in above analysts' estimates. Concerns about higher gas prices and inflation had knocked the gauge down in March and April.Despite those disappointing data, analysts still held a bullish view toward the stock market. "Despite our near-term caution, we continue to see the S&P 500 reaching 1400 over the coming year," Alec Young, equity strategist of S&P Equity Research told Xinhua.According to Alex, while recent macro headwinds were raising questions about the sustainability of recent earnings momentum, he still believed that a downside trend of market was fairly limited and that the current weakness is more likely to be a correction, rather than the beginning of a new bear market."In our view, 2011 estimated EPS would have to be excessively optimistic to justify a bear market,"he added.The Dow Jones industrial average added 38.82 points, or 0.31 percent, to 12,441.58. The Standard & Poor's 500 was up 5.41 points, or 0.41 percent, to 1,331.10. The Nasdaq Composite Index rose 13.94 points, or 0.50 percent, to 2,796.86.

SANAA, Feb. 5 (Xinhua) -- The Somali pirates hijacked a Chinese-flagged commercial ship off Yemen's western city port of al- Hudaida in the Red Sea, Chinese military attache to Yemen confirmed to Xinhua on Saturday.The Chinese military confirmed that the Chinese-flagged commercial ship, which was registered in Hongkong, China, had been hijacked by the Somali pirates off the Yemeni coast, Chinese military attache to Yemen told Xinhua.The ship was then moved by the pirates towards the Somali coasts, he added, without providing how many people were on board or the date of the hijack.Earlier, Yemeni Interior Ministry said the Chinese ship called "Tien Hau" was attacked by the pirates some 11 nautical miles (20. 4 kilometers) off the Yemeni island of Al-Tair off the city port of al-Hudaida.Meanwhile, a security source at the ministry told Xinhua "the security operation room of the ministry received unconfirmed information that an anti-piracy international navy fleet might intercept the pirates and help release the Chinese ship.""We are following up the situation to confirm the release of the Chinese ship, as coast guard boats were dispatched to track the ship and pirates," he told Xinhua on condition of anonymity."The hijack took place early today, but we do not have exact information about the number of the ship's crew," he added.The Gulf of Aden is considered as one of the world's most dangerous waters because of rampant piracy.

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