Dutch masters exhibition in Beijing

    The 17th century Dutch Golden Age had several significant artists and a range of great pieces produced during the period—including Jan Vermeer's Young Woman at Virginal,Jan Lievens' Boy in a Cape,and Turban and Rembrandt's Self-Portrait with Shaded Eyes.

    Some of the most refined examples of the time,including the three pieces mentioned above,will make their debut（首次亮相）in China as part of a world tour of The Leiden Collection.

    If you go:

    9 a.m.-5 p.m.,June 17-Sept 3 (closed on Mondays).National Museum of China,I Wusi Avenue,Dongcheng district.010-6400-1476.

    Ticket: 50 yuan ($7)

    The Age of Mechanical Reproduction

    The Age of Mechanical Reproduction,the latest exhibition at the Riverside Art Museum,features 41 artworks of US pop icon Andy Warhol,covering art installations,paintings and photographs.Warhol's well-known installation Electric Chair is a highlight of the show,which is also its debut in Asia.

    If you go:

    10 a.m.-5 p.m.,through August 28 (closed on Mondays).The Riverside Art Museum,Hongyan Road,Chaoyang district.010-5309-2062.

    Ticket: 60 yuan

    Back with a bang

    Beijing-based hand Escape Plan will hold a concert in Beijing this weekend.The band is most famous for the song The Brightest Star in the Night Sky.

    If you go:

    7:30 p.m.,June 17.Beijing Worker's Gymnasium,Gongti Beilu,Chaoyang district.400-610-3721.

    Ticket: 280-980 yuan

    Purple clay teapots

    Yixing purple clay potteries are a vital part of Chinese pottery culture and have been included in China's list of national intangible cultural heritage（国家非物质文化遗产）.A selection of more than 80 purple clay teapots will go on display at the Poly Art Museum starting Friday.The exhibit will include a range of delicate teapot works of Ji Yishun,Wang Xiaolong and Gao Lijun,who are all inheritors（继承人）the time-honored（历史悠久的）pottery handicraft.

    If you go:

    9:30 a.m.-4:30 p.m.(closed on Sundays),through June 30.Poly Art Museum,New Poly Plaza,1 Chaoyangmen North Street 9.010-6500-8117.

    Ticket: 20 yuan

    Every week in China, millions of people will sit in front of their TVs watching teenagers compete for the title Character Hero, which is a Chinese-style spelling bee (拼写大赛). In this challenge, young competitors must write Chinese characters by hand. To prepare for the competition, the competitors usually spend months studying dictionaries.

    Perhaps the show's popularity should not be a surprise. Along with gunpowder and paper, many Chinese people consider the creation of Chinese calligraphy (书法) to be one of their primary contributions to civilization. Unfortunately, all over the country, Chinese people are forgetting how to write their own language without computerized help. Software on smart phones and computers allows users to type in the basic sound of the word using the Latin alphabet. The correct character is chosen from a list. The result? It's possible to recognize characters without remembering how to write them.

    But there's still hope for the paint brush. China's Education Ministry wants children to spend more time learning how to write.

    In one Beijing primary school we visited, students practice calligraphy every day inside a specially decorated classroom with traditional Chinese paintings hanging on the walls. Soft music plays as a group of six-year-olds dip brush pens into black ink. They look up at the blackboard often to study their teacher's examples before carefully attempting to reproduce those characters on thin rice paper. “If adults can survive without using handwriting, why bother to teach it now?” we ask the calligraphy teacher, Shen Bin, “The ability to write characters is part of Chinese tradition and culture,” she reasons. “Students must learn now so they don't forget when they grow up.” says the teacher.

    Modern festival-goers who worry about ending up with a dead mobile phone battery after days stuck in a muddy field with no electric plug power points may now have a solution—power boots.

    Mobile phone company European Telco Orange has introduced a phone charging prototype(原型)— a set of thermoelectric gumboots or Wellington boots with a “power generating sole” that changes heat from the wearer's feet into electrical power to charge battery-powered hand-helds.

    The boot was designed by Dave Pain, managing director at GotWind, a renewable energy company. Pain said the boot uses the Seebeck effect, in which a circuit made of two dissimilar metals conducts electricity if the two places where they connect are held at different temperatures. “In the sole（鞋底）of the Wellington boot there's a thermocouple and if you apply heat to one side of the thermocouple and cold to the other side it produces an electrical charge,” Pain said. “That electrical charge we then pass through to a battery which you'll find in the heel of the boot for storage of the electrical power for later use to charge your mobile phone.” These thermocouples are connected electrically, forming an array of multiple thermocouples (thermopile). They are then sandwiched between two thin ceramic wafers(薄片). When the heat from the foot is applied on the top side of the ceramic wafer and cold is applied on the opposite side, from the cold of the ground, electricity is made.

    But the prototype boot does have one shortcoming. You have to walk for 12 hours in the boots to make one hour's worth of charge.

    What happens inside the head of a soccer player who repeatedly heads a soccer ball. That question motivated a study of the brains of experienced players.

    Researchers at the Albert Einstein College of Medicine in New York selected 34 adults, men and women. All of the volunteers had played soccer since childhood and  now competed year﹣round in adult soccer leagues. Each filled out a detailed questionnaire developed especially for this study to determine how many times they had headed a soccer ball in the previous year, as well as whether they had experienced any known concussions in the past.

    Then the players completed computerized tests of their memory and other learning skills and had their brains scanned. using a complex new M.R.I. technique which can find structural changes in the brain that can't be seen during most scans.

    According to the data they presented, the researchers found that the  players who had headed the ball more than about 1, 100 times in the previous 12 months showed significant loss of white matter in parts of their brains involved with memory, attention and the processing of visual information, compared with players who had headed the ball less.

    This pattern of white matter loss is "similar to those seen in traumatic brain injury", like that after a serious concussion, the researchers reported, even though only one of these players was reported to have ever experienced a concussion.

    The players who had headed the ball about 1, 100 times or more in the past year were also generally worse at remembering lists of words read to them, forgetting the words far more often than players who had headed the ball less.

    On the night of December 8, 1992, when he was standing in a parking lot talking to friends, Tracy March jumped to the top of a car, as he had done a hundred times before. This time, though, Tracy lost his balance. His head struck the ground, hard.

    All night, Cory, Tracy's mother, stood next to her son, who was lying in a hospital bed, his brown eyes fixed in a lifeless stare. She remembered that Tracy had once mentioned organ donation. Maybe I can spare another family this pain, she thought. When the time came, she and her husband Bill signed the forms permitting his organs to be donated.

    Tracy was declared dead the next day. Twenty-four hours later, in a Boston hospital, Tracy's liver was made part of my husband, David, who was suffering from a hopeless liver disease.

    Months later, we learned from the local organ bank that the donor's parents wished desperately to meet someone who had gained life through the gift from their son. A meeting was arranged by the organ bank to bring together two families linked by the most bittersweet ties imaginable.

    The meeting was risky, but worth it. We talked for 3 hours. They showed us a picture of Tracy. We learned how he had lived and died. We learned something about Bill and Cory too.

    For the Marches, seeing David and knowing he was well seemed to ease their suffering. I'll never forget seeing David's tall figure stopped over Cory, her arms around his waist, as a mother would hug a son. For a long time they held each other tight. It was hard to know if she was saying hello or good-bye. Maybe she was saying both.

California has lost half its big trees since the 1930s, according to a study to be published Tuesday and climate change seems to be a major factor. 

The number of trees larger than two feet across has declined by 50 percent on more than 46, 000 square miles of California forests, the new study finds. No area was spared or unaffected, from the foggy northern coast to the Sierra Nevada Mountains to the San Gabriels above Los Angeles. In the Sierra high country, the number of big trees has fallen by more than 55 percent; in parts of southern California the decline was nearly 75 percent. 

Many factors contributed to the decline, said Patrick McIntyre, an ecologist who was the lead author of the study. Woodcutters targeted big trees. Housing development pushed into the woods. Aggressive wildfire control has left California forests crowded with small trees that compete with big trees for resources. 

But in comparing a study of California forests done in the 1920s and 1930s with another one between 2001 and 2010, McIntyre and his colleagues documented a widespread death of big trees that was evident even in wildlands protected from woodcutting or development. 

The loss of big trees was greatest in areas where trees had suffered the greatest water shortage. The researchers figured out water stress with a computer model that calculated how much water trees were getting in comparison with how much they needed, taking into account such things as rainfall, air temperature, dampness of soil, and the timing of snowmelt. 

Since the 1930s, McIntyre said, the biggest factors driving up water stress in the state have been rising temperatures, which cause trees to lose more water to the air, and earlier snowmelt, which reduces the water supply available to trees during the dry season.