Acknowledgments
This work has been partially supported by the following grants: ESC was partially supported by a grant from CNPq- Brazilian National Research Council, Brasília, Brazil (‘Universal Project’/2007) and FAPERJ- Fundação de Amparo à Pesquisa do Rio de Janeiro, Brazil (‘Pensa-Rio’ projects E-26/110.301/2007, E-26/110.268/2007, E-26/110.170.639/2007 and JCNE/2010, respectively).
Potential conflict of interest
Disclosure forms provided by the authors are available with the full text of this article at www.informahealthcare.com/lal