Chinese-American Nobel laureate Chen Ning Yang, center, and his wife Weng Fan leave hand-in-hand after a forum held by Tsinghua University to commemorate his 90th birthday in Beijing, June 30, 2012. Tsinghua University held an academic forum to celebrate the physicist and Nobel Prize winner's 90th birthday on Saturday, along with Yang's wife Weng Fan. [Photo/Asianewsphoto]
