Funding for this research was provided by:
CNPq Research Productivity, Brazil (302622/2015-2)
Text and Data Mining valid from 2018-03-29
Received: 8 February 2018
Accepted: 21 March 2018
First Online: 29 March 2018
Compliance with ethical standards
: The authors declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the review reported.