Wang, Ling
Wang, Ronghui
Kong, Byung-Whi
Jin, Sha
Ye, Kaiming
Fang, Weihuan
Li, Yanbin
Article History
Received: 26 September 2014
Accepted: 20 April 2015
First Online: 2 June 2015
Competing interests
: The authors declare no competing financial interests.