Funding for this research was provided by:
Beijing Technology and Innovation Service Development Research Fund (KM201710029004)
Nanyang Technological University
Beijing Municipal Science and Technology Commission, Adminitrative Commission of Zhongguancun Science Park (Z181100009218005)
Article History
Received: 20 January 2019
Accepted: 4 April 2019
First Online: 23 April 2019
Ethics approval and consent to participate
: This study was approved by the institutional ethics committee (IRB2017BM005). Signed consent was obtained from all participants before data acquisition.
: Not applicable
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