Received: 19 May 2017
Accepted: 11 May 2018
First Online: 29 May 2018
Ethics approval and consent to participate
: This research was approved by the ETH Human Research Ethics Committee (No. 2012-N-10). Participants were informed of the experimental procedures and risks and provided their written informed consent prior to attending several familiarisation sessions.
: The authors declare that they have no competing interests.
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