Du, Juan
Wang, Qingkai
Jiang, Guobao
Xu, Changwen
Zhao, Chujun
Xiang, Yuanjiang
Chen, Yu
Wen, Shuangchun
Zhang, Han
Article History
Received: 12 May 2014
Accepted: 15 August 2014
First Online: 12 September 2014
Competing interests
: The authors declare no competing financial interests.