1. Center for Disease Control and Prevention of Chaoyang District of Beijing, Beijing, China
2. State Key Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing, China
3. Beijing Ditan Hospital, Capital Medical University, Beijing, China
4. International Laboratory for Air Quality and Heath, World Health Organization Collaborating Centre for Air Quality and Health, School of Earth and Atmospheric Sciences, Queensland University of Technology, Brisbane, Queensland, Australia
5. Center for Health-Related Aerosol Studies, Department of Environmental & Public Health Sciences, University of Cincinnati, Cincinnati, Ohio, USA
6. Department of Energy, Environmental & Chemical Engineering, Washington University–St. Louis, St. Louis, Missouri, USA
7. Department of Environmental Science and Engineering and Department of Chemical Engineering, California Institute of Technology, Pasadena, California, USA