Funding for this research was provided by:
Japan Society for the Promotion of Science (JSPS KAKENHI grant No. JP17K01362)
Changi General Hospital–Singapore University of Technology and Design (Health Tech Innovation Fund (HTIF) award No. CGH–SUTD–2015–003)
Received: 28 November 2018
Accepted: 1 February 2019
First Online: 12 February 2019
Ethics approval and consent to participate
: This study was approved by the local Institutional Review Board of the Singapore University of Technology and Design, Singapore, and informed written consent was acquired from the volunteer.
: Not applicable.
: The authors declare that they have no competing interests.
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