This article was republished on June 22, 2015, to correct Figs 1 and 2, which were darker than intended. The publisher apologizes for the error. Please download this article again to view the corrected version.
Authors: Suvi Rautiainen; Mervi Könönen; Reijo Sironen; Amro Masarwah; Mazen Sudah; Juhana Hakumäki; Ritva Vanninen; Anna Sutela Journal: PLoS One Date: 2015-03-30 Impact factor: 3.240