Sci-Tech

2017-06-29 01:11
CHINA TODAY 2017年6期

Chinese Submersible Jiaolong Completes Dives in South China Sea

Jiaolong, Chinas manned submersible, conducted its ninth and final dive in the South China Sea, on May 10.

Jiaolong stayed underwater for nine and a half hours during its ninth dive in the second stage of Chinas 38th ocean scientific expedition, which lasted until May 13.

The maximum depth of the dive was 1,897 meters in the Puyuan Seamount.

The three crew members, who were on board the submersible, brought back samples of seawater and sediment from the seabed, high-definition photographs, and video footage.

The 38th oceanic scientific expedition started on Feb. 6. Jiaolong completed a dive in the northwestern Indian Ocean earlier this year as part of the missions first stage. It will also conduct surveys in the Yap Trench and the Mariana Trench during the third stage.

Named after a mythical dragon, Jiaolong completed its deepest dive of 7,062 meters in the Mariana Trench, in June 2012.

Chinese Scientists Uncover Variations of Lakes on Qinghai-Tibet Plateau

Scientists have identified three distinct periods over the past four decades that feature notably different variations of lake area and volume on the Qinghai-Tibet Plateau.

Zhang Guoqing, a researcher with the Chinese Academy of Sciences (CAS) Center for Excellence in Tibetan Plateau Earth Sciences, was part of a team of domestic and foreign scientists that examined annual changes in lake area, level and volume from the 1970s to 2015.

The team found that the three indexes changed at similar rates. They saw a slight decline from the 1970s to 1995, followed by a rapid increase from 1996 to 2010, and then a recent deceleration during the period from 2011 to 2015.

They also found that increased precipitation contributed the most to lake volume increases, followed by glacier mass loss and the melting of ground ice due to permafrost degradation.

These results suggest that the hydrological cycle on the plateau has intensified remarkably during recent decades.

Minor Planet Named After Chinese Aerospace Scientist

Minor Planet No. 456677 was named after Chinese aerospace scientist Ye Peijian at a ceremony on May 8, 2017. Ye is a key contributor to the countrys lunar probe and deep space missions, and an academician of the Chinese Academy of Sciences. The minor planet was discovered by a Chinese team at the Purple Mountain Observatory in Nanjing, on Sept. 11, 2007. The naming suggestion was approved by the International Astronomical Unions Minor Planet Center on January 12, 2017.

Macao Researchers Develop Room Temperature Storage Technology for Stem Cells

University of Macao (UM) researchers have developed a new way to store stem cells at room temperature for a minimum of seven days without the loss of viability and biological activity, according to the universitys latest news release on May 4.

UM said researchers from the Faculty of Health Sciences (FHS) have developed a technology which does not rely on the traditional cryopreservation method which requires costly equipment and lengthy procedures. The new process will enable cell storage and transport under ambient conditions.

Xu Renhe, a professor at the FHS, has nearly two decades of research experience with stem cells and their medical applications. He and his doctoral student Jiang Bin and postdoctoral researcher Yan Li, together with Dr. Chris Wong Koon Ho, an assistant professor at the FHS, have completed a study entitled “Spheroidal Formation Preserves Human Stem Cells for Prolonged Environment under Ambient Conditions for Facile Storage and Transportation.”

The study found that making human mesenchymal stem cells (hMSC) form spheroids with the hanging-drop method or other methods can reduce cell metabolism and increase cell viability.

Stored in a sealed vessel filled with regular culture medium, under airtight, ambient conditions, the viability of hMSC in spheroids remained over 90 percent even after 11 days. This method is also applicable to higher pluripotent human embryonic stem cells.

In theory, with this new technology, the only thing required for storing and shipping any type of stem cells and non-stem cells that can aggregate (within a temperature range of 10 to 37 degrees centigrade) are regular culture tubes and petri-dishes, which cost only several U.S. dollars.

Stem cells are found in various parts of the body, such as bone marrow, blood, the brain, the spinal cord, skin, and the corneal limbus. They are responsible for regenerating and repairing damaged tissue and organs in the body.