UK PubMed Central has been renamed as Europe PubMed Central.
Here's an excerpt from the announcement:
As announced in July, the European Research Council (ERC) becomes the third European funder to join UKPMC, following Telethon Italy and the Austrian Research Fund. As a result of this participation, the 18 existing UK and European funders agreed that the UKPMC service should be rebranded as Europe PMC by 1 November 2012. . . .
UKPMC was originally launched in January 2007, initially as a mirror of the US National Institute of Health's PubMed Central (PMC), providing international preservation of open- and free-access biomedical literature. The UKPMC funders require that research papers funded by them must be made freely available via UKPMC no later than 6 months after publication.