Combo photo shows young teacher Wang Shuzhen (R) guiding her student conduct an experiment at Yan'an University in Yan'an, northwest China's Shaanxi Province on July 19, 1961 (L, file photo) and students performing experiments at Yan'an University in Yan'an on May 6, 2019 (R, taken by Liu Xiao). Yan'an, a former revolutionary base of the Communist Party of China (CPC), is no longer labeled "poor," as its last two impoverished counties have shaken off poverty, the Shaanxi provincial government announced Tuesday. (Xinhua)