HONG KONG (Reuters Life!) - Just over 30 years ago, not long after the death of Mao Zedong, a group of young Chinese artists staged an exhibition that pushed back on a decade of tyranny and helped pave the way for Chinese art's global rise. Artwork was hung outside Beijing's National Art Gallery in 1979, as artists demanded artistic freedoms. Perhaps the best known of these dissidents is Ai Weiwei whose works sell for millions now in New York art galleries and global auction halls.