Correction

After publication of this Research Article [1], we noted that figure 2 and 3 had been swapped round. The correct images can be seen below:

figure 2

Figure 2

figure 3

Figure 3

This error was introduced during the final production process by the publisher and BioMed Central apologises for any inconvenience caused.

Figure 1 for the Research Article [1] can also be seen below for reference:

figure 1

Figure 1

Pre-publication history

The pre-publication history for this paper can be accessed here: http://www.biomedcentral.com/1753-6561/8/S2/S9