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WASHINGTON, May 4 (Xinhua) -- The U.S. National Aeronautics and Space Administration (NASA) announced Wednesday that its Gravity Probe B (GP-B) mission has confirmed two key predictions derived from Albert Einstein's general theory of relativity, which the spacecraft was designed to test.The experiment, launched in 2004, used four ultra-precise gyroscopes to measure the hypothesized geodetic effect, the warping of space and time around a gravitational body, and frame- dragging, the amount a spinning object pulls space and time with it as it rotates.GP-B determined both effects with unprecedented precision by pointing at a single star, IM Pegasi, while in a polar orbit around Earth. If gravity did not affect space and time, GP-B's gyroscopes would point in the same direction forever while in orbit. But in confirmation of Einstein's theories, the gyroscopes experienced measurable, minute changes in the direction of their spin, while Earth's gravity pulled at them.The findings are available online in the journal Physical Review Letters."Imagine the Earth as if it were immersed in honey. As the planet rotates, the honey around it would swirl, and it's the same with space and time," said Francis Everitt, GP-B principal investigator at Stanford University. "GP-B confirmed two of the most profound predictions of Einstein's universe, having far- reaching implications across astrophysics research."GP-B is one of the longest running projects in NASA history, with agency involvement starting in the fall of 1963 with initial funding to develop a relativity gyroscope experiment. Subsequent decades of development led to groundbreaking technologies to control environmental disturbances on spacecraft, such as aerodynamic drag, magnetic fields and thermal variations. The mission's star tracker and gyroscopes were the most precise ever designed and produced.GP-B completed its data collection operations and was decommissioned in December 2010."The mission results will have a long-term impact on the work of theoretical physicists," said Bill Danchi, senior astrophysicist and program scientist at NASA Headquarters in Washington. "Every future challenge to Einstein's theories of general relativity will have to seek more precise measurements than the remarkable work GP-B accomplished."

JERUSALEM, April 12 (Xinhua) -- Israeli-Canadian archaeologist Simcha Jacobovici may have stumbled upon a major archaeological find if his claim of unearthing the nails used to hold Jesus on the cross during his crucifixion are to be believed.Jacobovici maintains that small metal remains dug out of the soil in a cave in a Jerusalem neighborhood are in fact the nails that held Jesus on the cross, the Ha'aretz daily reported Tuesday.The artifacts were found in a cave in the Armon Hanatziv ridge, about 6 km south of the Old City, during the course of a construction work in 1990. The hilly area now contains apartment buildings.During the excavation of the cave, a stone vessel with the name Caiaphas, the name of the High Priest considered responsible for turning Jesus over to the Romans, and two rusty nails, which Jacobovici believes to be the relics, was unearthed.However, officials from the Israeli Antiquities Authority told Xinhua although they regard Jacobovici as a great archaeologist and documentary filmmaker, they do not believe the cave really belongs to the High Priest of the Second Temple period (between 536 BC and 70 AD)."The reason is that during that period of time there were a lot of people with the name Caiaphas," a statement from the Antiquities Authority said, "And for example, it is inconceivable that every gravestone bearing the name Moshe Dayan, which is very common in these parts, should be ascribed to the same personality who played so prominent a role in our recent history."Dayan was an Israeli army general who led his troops to victory in the 1967 war.The authority considers Jacobovici's contention as "fantasy" that should not be considered conclusive, since there is no agreed- upon evidence backing it up.Jacobovici is standing his ground, however, and contends that during the Second Temple Period the name Caiaphas was uncommon, and therefore the tomb must belong to the infamous priest.Jacobovici, a well-known documentary filmmaker, has produced films about the Israeli-Palestinian conflict and human trafficking that earned him two Emmy Awards.He also worked alongside film director James Cameron on the movie Jesus' Lost Tomb.He expects to soon release a movie about the latest finds, entitled Nails on the Cross.

SAN FRANCISCO, April 22 (Xinhua) -- Apple and Google collect smartphone users' location information as part of their race to build massive databases, The Wall Street Journal reported on Friday after analyzing data and documents.According to the report, security analysts with the newspaper found that Apple's iPhone and smartphones running Google's Android operating system regularly transmit users' locations back to the two companies respectively, which is part of their race to build databases capable of pinpointing people's locations via smartphones.A report by research firm Gartner indicated that the market for location-based services is expected to rise to 8.3 billion U.S. dollars in 2014 from the current 2.9 billion dollars.In the case of Google, a security analyst with The Wall Street Journal said an HTC Android phone collected name, location, signal strength of any nearby Wi-Fi networks, and a unique phone identifier every few seconds and transmitted the data to Google at least several times an hour."All location sharing on Android is opt-in by the user," Google said in a statement to technology blog site All Things Digital, in response to the concern that how Android system uses location information."We provide users with notice and control over the collection, sharing and use of location in order to provide a better mobile experience on Android devices. Any location data that is sent back to Google location servers is anonymous and is not tied or traceable to a specific user," said the statement.Worries on the iPhone tracking issue surfaced on Wednesday after two British researchers announced at a technology conference in California that iPhone has been collecting users' location information and storing the data for extended periods of time.The researchers said starting on June 21 2010, after the release of iOS 4 mobile operating system, iPhones began logging and storing location information in a file, which shows the users' latitude and longitude and is timestamped to the second. They noted the information is not encrypted on the phone or on the iPhone backups made by iTunes and the file is also persistent, transferring itself to a new iOS device when the old one is replaced.They added they had no evidence that the file was being transmitted to Apple.On Thursday, U.S. congressman Edward Markey reacted angrily to the news in a letter to Apple CEO Steve Jobs, which is posted on Markey's official website.Markey asked Jobs to make a response within 15 business days or no later than May 12, saying "Apple needs to safeguard personal location information of its users to ensure that an iPhone doesn't become an iTrack."Apple has made no comment on the issue so far, but a letter it sent to U.S. Congress last July came under spotlight. In the letter, Apple said it collects Wi-Fi and GPS information when the phone is searching for a cellular connection and gathers the data to help build a "database with known location information."

HOUSTON, May 2 (Xinhua) -- The Offshore Techonology Conference, one of the world's largest offshore technology shows, kicked off here Monday.The five-day event, which attracted an estimated 72,000 victors from all around the world, not only provided a platform for the about 2,400 participating companies from 40 countries to lure visitors with their newest products and technologies, but also for the them to share insights and discuss issues the industry is facing.On Monday, a number of companies, including Halliburton and Baker Hughes, received the Spotlight on New Technology Award by the OTC for their new products and solutions.Founded in 1969, the annual Offshore Technology Conference is the world's foremost event for the development of offshore resources in the fields of drilling, exploration, production, and environmental protection. OTC is held annually at Reliant Center in Houston.

BEIJING, March 17 (Xinhuanet) -- A new study has shown that gene therapy can reduce symptoms in patients with Parkinson's, media reports said Thursday.The study, published in the journal Lancet Neurology, is the first to show positive results in a test of gene therapy against a sham operation in 45 U.S. Parkinson's patients.The treated group showed a 23.1 percent improvement on a scale of Parkinson's symptoms six months after treatment, compared to a 12.7 percent improvement for patients who received sham surgery, according to the published research."Gene therapy is no longer just a theory," said Michael Kaplitt, a neurosurgeon at New York-Presbyterian Hospital and Weill Cornell Medical Center, and one of the study authors. "We are getting much closer to a reality where this treatment can be offered to patients."In patients with Parkinson's disease, their brains get overactive after losing the normal supply of a chemical called GABA. The new treatment, gene therapy, works by inserting billions of copies of a gene into patients' brains that helps them produce more GABA.Kaplitt said the results might spur similar treatments for other brain disorders like Alzheimer's, epilepsy and depression.

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