Correction to: Scientific Reports https://doi.org/10.1038/s41598-017-11037-y, published online 31 August 2017

This Article contains an error in the Acknowledgements section.

“Fundamental Research Funds for the Central Universities, Huazhong University of Science and Technology (2016YXMS215), Wuhan, China.”

should read:

“National Natural Science Foundation of China (NSFC, 71373090, “Study on the gatekeeper policy of CHS”).”