Sun, Cheng http://orcid.org/0000-0003-0474-7593
Kucharski, Fred
Li, Jianping
Jin, Fei-Fei
Kang, In-Sik
Ding, Ruiqiang
Article History
Received: 12 January 2017
Accepted: 22 May 2017
First Online: 7 July 2017
Competing interests
: The authors declare no competing financial interests.