Acknowledgements
Funding: The authors declare that they received no funding for
the present study.
Conflict of interest: The authors declare that they have no
conflict of interest.
Ethical approval: All procedures performed in this study 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.
Informed consent: Informed consent was obtained from all
individual participants included in the study.