1. a Faculty of Public Health, College of Health Sciences , Kaohsiung Medical University , Kaohsiung
2. b Division of Environmental Health and Occupational Medicine , National Health Research Institutes , Miaoli
3. c Department of Health Care Administration , I-Shou University , Kaohsiung
4. d Department of Pharmacology, College of Medicine , Kaohsiung Medical University , Kaohsiung, Taiwan