Sun, Yu https://orcid.org/0000-0002-2938-0233
Hu, Guorui
Luo, Jihang
Fang, Di
Yu, Yongguo
Wang, Xiang
Chen, Jing
Qiu, Wenjuan
Article History
Received: 26 September 2016
Revised: 31 December 2016
Accepted: 3 January 2017
First Online: 2 February 2017
Competing interests
: The authors declare no conflict of interest.
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