Author Affiliations +
Shinichi Watanabe,1,* Masako Izawa2
1aGraduate School of Engineering and Science, University of the Ryukyus, Okinawa 903-0213, Japan
2bDepartment of Chemistry, Biology and Marine Science, University of the Ryukyus, Okinawa 903-0213, J
**To whom correspondence should be addressed. E-mail: h063019@sci.u-ryukyu.ac.jp (or izawa@sci.u-ryukyu.ac.jp)