Institution: | (1) Environmental Resources Research Center, Okayama University of Science, 700 Okayama, Japan;(2) Department of Public Health, City of Okayama, 700 Okayama, Japan;(3) Lanzhou Institute of Plateau Atmospheric Physics, Academia Sinica, Lanzhou, Gansu, P. R. China;(4) Present address: College of Liberal Arts and Sciences, Okayama University, 700 Okayama, Japan |