Funding for this research was provided by:
NSFC (61572158, 61602132)
Shenzhen Science and Technology Program (JSGG20150512145714247, JCYJ20160330163900579)
Shenzhen Science and Technology Program (JCYJ20170413105929681)
Article History
Received: 8 November 2017
Accepted: 8 January 2018
First Online: 25 January 2018
Compliance with ethical standards
:
: No conflict of interest exits in the submission of this manuscript.