Ding, Ying
Zhang, Rong-Yi
He, Bing
Liu, Zhou
Zhang, Ke
Ruan, Jing-Wen
Ling, Eng-Ang
Wu, Jin-Lang
Zeng, Yuan-Shan
Article History
Received: 29 October 2014
Accepted: 16 February 2015
First Online: 16 March 2015
Competing interests
: The authors declare no competing financial interests.