Jiong Tu1, Chunxiao Wang2, Shaolong Wu3. 1. School of Sociology and Anthropology, and Center for Medical Humanities, Sun Yat-sen University, Guangzhou, 510275 China. 2. School of Government, Sun Yat-sen University, Guangzhou, 510275 China. 3. School of Public Health and Global Health Institute, Sun Yat-sen University, Guangzhou, 510275 China. Electronic address: wushlong@mail.sysu.edu.cn.