Funding for this research was provided by:
Conselho Nacional de Desenvolvimento Científico e Tecnológico (457931/2014-0)
Text and Data Mining valid from 2018-05-23
Received: 19 January 2018
Accepted: 1 May 2018
First Online: 23 May 2018
Compliance with Ethical Standards
: The authors declare that they have no conflict of interest.