Ｓｃｉ－ｔｅｃｈ　Ｉｎｆｏ

Satellite Navigation System to Serve in the Beijing Olympics

The China-developed satellite navigation system Beidou (Big Dipper) is to be employed during the 2008 Olympic Games. By analyzing data received from traffic departments and five positioning satellites orbiting the earth, the system can inform drivers of their exact position and let them know the best route to their destination in the given traffic conditions.

Beidou is one of the worlds four leading satellite navigation systems. The others are GPS of the U.S., Glonass of Russia and Galileo of Europe.

First Change-1 Pictures of the Moon Made Public

China National Space Administration (CNSA) released the first moon image captured by the Change-1 moon orbiter on November 26, 2007. The picture, taken by a stereo camera, covers an area exceeding 130,000 square kilometers, or 0.3 percent of the moons surface. Change-1 is Chinas first lunar probe and was launched on October 24, 2007. It smoothly entered the moons orbit on November 7 after eight orbital transfers. It is scheduled to send back a flow of data to scientists on earth for 12 months.

Cultivating Pluripotent Stem Cells from Skin

Research teams from the United States and Japan recently announced they had successfully converted human skin cells so they resembled embryonic stem cells, a breakthrough that might sidestep the ethical stumbling blocks surrounding the use of stem cells obtained from human embryos.

The American team is headed by Dr. Junying Yu, a graduate of Peking University who went to the U.S. in 2003. The teams both used genetic reprogramming techniques to introduce new elements into skin cells to make them indistinguishable from embryonic stem cells. The Japanese reprogrammed cells of the human face, while the Americans worked with human fibroblasts. Both teams agree, however, there is a long way to go before their research can be put to practical use.

New AIDS Vaccine Enters

Preliminary Clinical Tests

DNA-Tiantan AIDS vaccine, jointly developed by China CDC and the National Vaccine and Serum Institute, was given to the first group of volunteers in Beijing Union Hospital on December 1, 2007. It is the worlds only replicating vector AIDS vaccine presently undergoing clinical trials.

The new live vaccine is made up of DNA vaccine and recombined virus carrier. Its immunogen is the most prevalent HIV strain in China -- CRF-07. The carrier is the Tiantan recombinant vaccinia virus, formerly a popular carrier for smallpox vaccines, whose credibility has been proven in widespread application. Animal tests show that the new AIDS vaccine can induce an immune response in both body liquids and cells in rats and monkeys, preventing them from being infected by the virus. The test has been approved by the State Food and Drug Administration.

Monitoring System for Empty Nesters

Hong Kong Polytechnic University recently invented a monitoring system for the elderly living alone. It operates through a wireless sensor installed in abodes that monitors the indoor activities of aged occupants. When anything suspicious is noticed, such as a lack of motion for a prolonged period, personnel are alerted to make inquiries. Another component of the system is a life signal sensor worn on the ear that monitors elderly peoples heartbeat and body temperature. It sets off an alarm whenever abnormalities are found. The system also features a positioning service on GSM mobile phones, tailor-made for Alzheimer Dementia sufferers.

Fiber Laser to Enter Production

China has reported success in making a fiber laser of 25W, and is planning to begin mass production as soon as possible. No bigger than an average desktop computer, a fiber laser can evenly pierce ten holes on the tip of a thread of human hair. It is more energy efficient than other types of laser, is more stable and features a better ray quality. It is widely used in precision welding, cutting, marking and medical equipment. China needs approximately 5,000 fiber laser devices every year. Thanks to this technical breakthrough by Chinese scientists, the country will now have domestically-produced fiber lasers, predicted to cost 40 percent less than imported models.

Ocean Bottom Seismic Detector “Sees” 100 Meters into the Seabed

China recently produced a seaquake detector that surveys the seabed by sending shock waves to pre-set locations. The shock waves travel through the ocean to reach the sea floor before being reflected back and detected by high-precision cables. Information from the cables is processed by computer software into geological data.

The equipment can probe the structure and strata of the seabed more than 100 meters beneath the seafloor, and swiftly report any unusual geological structures. The error margin is less than 0.3 meters. The ability to gather such data is crucial for offshore oil and gas exploitation and geological engineering projects, effectively warding off unnecessary economic losses.

New Detector Sniffs Out Explosives

The SIM (Subscriber Identity Module) explosives detector, developed by the Shanghai Institute of Microsystems and Information Technology (SIMIT), can discern traces of nine common explosives with a precision level of 4 ppt. It is expected to be widely deployed at airport security checkpoints, sporting events and entrances to government buildings.

The detector employs sensor technology based on the fluorescence quenching effect produced by explosive molecules in response to particular fluorescence polymers. It searches for explosive materials, such as TNT, by judging the fluorescence strength of these polymers.