Guan, Xiao
Liu, Longfei
Lei, Xiang
Zu, Xiongbing
Li, Yuan
Chen, Mingfen
Wang, Long
Qi, Lin
Article History
Received: 10 July 2014
Accepted: 10 October 2014
First Online: 29 October 2014
Change Date: 12 February 2015
Change Type: Update
Change Details: A correction has been published and is appended to both the HTML and PDF versions of this paper. The error has been fixed in the paper.
Competing interests
: The authors declare no competing financial interests.