Zhao, Hongtu
Sheng, Gang
Wang, Jiuyu
Wang, Min
Bunkoczi, Gabor
Gong, Weimin
Wei, Zhiyi
Wang, Yanli
Article History
Received: 20 June 2014
Accepted: 5 August 2014
First Online: 12 August 2014
Competing interests
: The authors declare no competing financial interests.