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WASHINGTON, Sept. 12 (Xinhua) -- An enzyme that appears to play a role in controlling the brain's response to nicotine and alcohol in mice might be a promising target for a drug that simultaneously would treat nicotine addiction and alcohol abuse in people, U.S. researchers find.Over the course of four weeks, mice genetically engineered to lack the gene for protein kinase C (PKC) epsilon consumed less of a nicotine-containing water solution than normal mice, and were less likely to return to a chamber in which they had been given nicotine. In contrast, normal mice steadily increased their consumption of nicotine solution while the mice lacking PKC epsilon did not.The study conducted by researchers at the Ernest Gallo Clinic and Research Center, affiliated with the University of California, San Francisco, appeared Monday in the online edition of the Proceedings of the National Academy of Sciences.In normal mice, as in humans, nicotine binds to a certain class of nicotinic receptors located on dopamine neurons, which causes dopamine to be released in the brain. Dopamine creates a feeling of enjoyment, and thus prompts a sense of reward. Researchers found that mice lacking PKC epsilon are deficient in these nicotinic receptors.The finding complements earlier research in which researchers found that mice genetically engineered to lack the PKC epsilon enzyme drank less alcohol than normal mice and were disinclined to return to a chamber in which they had been given alcohol."This could mean that these mice might not get the same sense of reward from nicotine or alcohol," said Gallo senior associate director and investigator Robert Messing. "The enzyme looks like it regulates the part of the reward system that involves these nicotinic receptors."The reward system is a complex of areas in the brain that affect craving for nicotine, alcohol and other addictive substances.The next step in the research, said Messing, would be to develop compounds that inhibit PKC epsilon. The ultimate goal, he added, would be medications that could be used "to take the edge off of addiction by helping people get over some of their reward craving."

BEIJING, Aug. 12 (Xinhuanet) -- Engineers at the University of Illinois have unveiled novel, skin-mounted electronics whose circuitry bends, wrinkles, and even stretches with skin, according to media reports quoting the Science Friday.The device platform includes electronic components, medical diagnostics, communications, and human-machine interfacing on a patch so thin and durable that it can be mounted to skin much like a temporary tattoo, the jounral described.What's more, the engineers demonstrated the invention across a wider range of components, including LEDs, transistors, wireless antennas, sensors, and conductive coils and solar cells for power."We threw everything in our bag of tricks onto that platform, and then added a few other new ideas on top of those to show that we could make it work," said engineering professor John A. Rogers in a news release.

MOSCOW, Aug. 26 (Xinhua) -- Russia will carry out two unmanned test launches of Soyuz carrier rockets in the coming fall before delivering crews to the International Space Station (ISS), local media reported on Friday.Citing a source, RIA Novosti news agency said that one of the Soyuz rockets was scheduled to send a new Progress M-13M space freighter to the ISS.On Wednesday, a Progress M-12M cargo ship failed to reach the orbit after the engine of a Soyuz-U carrier rocket turned off during the ascend. Soon after the accident, Russia announced it will temporarily ground all Soyuz rockets.Due to the accident, Russian space authorities have put off Thursday's launch of a Soyuz-2 carrier rocket from the Plesetsk Space Center in northern Russia and a launch of a manned space ship from Baikonur space center in Kazakhstan.After the retirement of the U.S. shuttle fleet, Russia's Soyuz spacecrafts have become the only way for astronauts to reach the ISS until at least the middle of the decade.

BEIJING, Sept. 23 (Xinhua) -- A defunct U.S. satellite is expected to crash down to Earth Friday, with nobody knowing where or when exactly it will hit. This was avoidable, a Chinese expert said Thursday.Pang Zhihao, a researcher from the Chinese Research Institute of Space Technology, told Xinhua that the crash could have been avoided had the satellite been put into a higher orbit, or manipulated to drop in the South Pacific when it had abundant fuel. It would pose no threat to Earth if these measures had been taken.NASA's tumbling, 5,900 kg Upper Atmosphere Research Satellite, or UARS, is the first of such man-made space vehicles that have been launched into outer space according to the agency's Mission to Planet Earth. The mission was launched in the 1990s.The mission is designed to provide data for better understanding Earth's upper atmosphere and the effects of natural and human interactions on the atmosphere.The satellite was deactivated in 2005 as it ran out of fuel and was left orbiting Earth like a big piece of space junk.There are other cases of defunct satellites. The European Space Agency said earlier its observation satellite ERS-2 has run out of fuel and is deorbiting. It would therefore also crash sooner or later.Pang said all countries which are operating space vehicles should take care of their own spacecrafts so that they won't pose any danger.The expert also said that the public need not worry too much.Pang said most spacecrafts will be incinerated upon re-entering Earth's atmosphere, and the debris will mostly likely fall into the ocean or hit an uninhabited area. In addition, a debris tracker is able to give a comparatively accurate prediction where the craft will fall about two hours before it hits Earth, giving residents, if there are any, time to evacuate.He added that there are several ways to minimize the threat of decommissioned spacecrafts, like putting them into higher orbits and crashing them into designated waters.Scientific progress would possibly bring about more ways of dealing with tumbling satellites. Scientists have already been trying to build spacecrafts with degradable materials so that they can self-destruct when re-entering Earth's atmosphere.

BEIJING, July 25 (Xinhuanet) -- More than one in three births in the U.S. are  delivered by C-section, which is an all time high and an increase of 25 percent over seven years, according to news reports Monday quoting a new study.Based on data from 19 states, C-section, or Cesarean, deliveries shot up from 27 percent of all births in 2002 to 34 percent in 2009, said the study by HealthGrades.  HealthGrades is an independent health care ratings organization with information on physicians, dentists and 5,000 hospitals in the nation.The study noted that the states with the highest rates are Texas, New Jersey and Florida while Utah, Colorado and Wisconsin are the lowest.Experts hold C-section deliveries are most suitable when vaginal delivery puts the health of the woman or child at risk, but also attributing the reason of increase to convenience, less risk, fertility and general attitudes.However, Divya Cantor, MD, MBA and HealthGrades Senior Physician Consultant. cautioned, "C-sections are rising, and there needs to be a little bit more scrutiny from the person who is having the C-section as well as doctors and hospitals."

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