Guo, Xiang
Zou, Chang-ling
Schuck, Carsten http://orcid.org/0000-0002-9220-4021
Jung, Hojoong
Cheng, Risheng http://orcid.org/0000-0003-2095-463X
Tang, Hong X
Article History
Received: 1 June 2016
Revised: 27 October 2016
Accepted: 27 October 2016
First Online: 7 November 2016
Competing interests
: The authors declare no conflict of interest.