Chinese Vice Premier Liu Yandong (2nd L) meets with John Holdren (1st R), assistant to U.S. President Obama for Science and Technology and director of the White House Office of Science and Technology Policy, in Washington D.C., the United States, on June 23, 2015. The meeting was held here Tuesday on the sidelines of the seventh China-U.S. Strategic and Economic Dialogue (S&ED) and the sixth China-U.S. High-Level Consultation on People-to-People Exchange (CPE). (Xinhua/Wang Lei)