Scientific Reports 5: Article number: 13243; published online: 19 August 2015; updated: 08 October 2015.

The Acknowledgements section in this Article is incomplete.

“This work was supported by Portuguese Foundation for Science and Technology (FCT) grants PTDC/SAU-ORG/119296/2010, PTDC/SAU-ORG/118694/2010 and PEST-C/SAU/UI3282/2013-COMPETE.”

should read:

“This work was supported by Portuguese Foundation for Science and Technology (FCT) grants PTDC/SAU-ORG/119296/2010, PTDC/SAU-ORG/118694/2010, PEST-C/SAU/UI3282/2013-COMPETE and FCT-UID/NEU/04539/2013.”