If the authors are around, you're missing some backslashes before your dollar signs, here: http://www.pnas.org/content/103/46/17184.full#sec-3 http://www.pnas.o

If the authors are around, you're missing some backslashes before your dollar signs, here: http://www.pnas.org/content/103/46/17184.full#sec-3 http://www.pnas.org/content/103/46/17184.full#sec-3