1. University of South Carolina Arnold School of Public Health, Columbia, South Carolina, USA
2. Department of Reproductive Health and Research, World Health Organization, Geneva, Switzerland
3. Department of Physics and Atmospheric Science, Dalhousie University, Halifax, Nova Scotia, Canada
4. School of Medicine, Universidad Nacional Autónoma de México, Mexico City, Mexico
5. Instituto Nacional de Medicina Genomica, Mexico City, Mexico
6. Harvard-Smithsonian Center for Astrophysics, Cambridge, Massachusetts, USA