Funding for this research was provided by:
National Natural Science Foundation of China (61070226)
ORCID
Liang DOU: http://orcid.org/0000-0003-3044-3841
Publication History
Received: 2016-04-24
Accepted: 2016-06-30
Crosschecked: 2017-11-29
Content Type
: Article
Copyright
: © Zhejiang University and Springer-Verlag GmbH Germany 2017