1. School of Public Health, University of Nevada, Reno, Reno, Nevada, USA
2. Ozmen Institute for Global Studies, University of Nevada, Reno, Reno, Nevada, USA
3. Departments of Geography and Demography, Penn State University, University Park, Pennsylvania, USA
4. Center for Tobacco Control Research and Education, University of California, San Francisco, San Francisco, California, USA
5. Division of General Internal Medicine, Dept of Medicine, University of California, San Francisco, San Francisco, California, USA