Funding for this research was provided by:
CTI Commission of Technology and Innovation Switzerland (Nr. 16978.1 PFES-ES)
Received: 19 July 2017
Accepted: 2 November 2017
First Online: 1 December 2017
: All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards. The study protocol was approved by the Ethical Committee of the Kanton St.Gallen, Switzerland (Ref. EKSG14/101).
: The authors declare that they have no competing interests.
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