CCL: Papers using PCA to compare MD conformations to crystal structures?

 Sent to CCL by: "Ian  Craig" [ianrcraig[*]gmail.com]
 Dear All,
 I am looking for papers in which Principal Component Analysis (or similar) is
 used to compare the protein conformations visited by an MD trajectory to a set
 of crystal (or NMR) structures.
 I imagine this must have been done in this past to characterize the extent of
 conformational sampling accomplished by MD simulations. However, I am having
 trouble tracking down firm examples.
 If anything springs to mind (even if it is just a name and a rough estimate of
 the year), I would greatly appreciate it.
 Regards,
 Ian.