1. School of Business; Nanjing University; Nanjing China
2. China Economics and Management Academy; Central University of Finance and Economics; Beijing China
3. School of Social Development and Public Policy; Fudan University; Shanghai China
4. Center for Healthy Aging and Development Studies, National School of Development; Peking University; Beijing China
5. Center for the Study of Aging and Human Development, Geriatrics Division of School of Medicine; Duke University; Durham NC USA