1. Graduate Academy, Party School of the Central Committee of the Communist Party of China (National Academy of Governance), Beijing, China
2. Department of Non-communicable Chronic Disease, Qingdao Municipal Center for Disease Control & Preventation, Qingdao, China
3. School of Business, Qingdao University, Qingdao, China
4. School of Economics, Qingdao University, Qingdao, China