The authors declare that they have no competing interests.
CK was primarily responsible for drafting manuscript and incorporated revisions suggested by co-authors. All co-authors (TH, JS, BC, CW, RK, DK, TZ, HL, JL, JI, JA) were equally responsible for writing, revising, and providing feedback for submission. All authors reviewed content for scientific merit and provided general recommendations in relation to the direction of the manuscript. All authors have read and approved the final manuscript.
The online version of the original article can be found at 10.1186/1550-2783-5-17