Yin, Hongping
Deng, Yifeng
Wang, Huafu
Liu, Wugao
Zhuang, Xiyi
Chu, Weihua
Article History
Received: 1 June 2015
Accepted: 7 October 2015
First Online: 9 November 2015
Change Date: 12 January 2016
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.