Text and Data Mining valid from 2018-12-18
Received: 11 September 2018
Accepted: 5 December 2018
First Online: 18 December 2018
Compliance with ethical standards
: The authors declare that they have no conflict of interest.
: Data generated during the course of the current study re available from the corresponding author on reasonable request.
: Informed consent was obtained from all individual participants included in the study.
: 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.
: No animals were used in this study.