Text and Data Mining valid from 2017-07-21
Received: 15 November 2015
Accepted: 17 July 2017
First Online: 21 July 2017
Compliance with Ethical Standards
: All authors declare that they have no conflict of interest.
: The procedure performed in the study was 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.
: This article does not contain any studies with animals performed by any of the authors.
: Informed consent was obtained from the individual participant included in the study.