Michael J Fox makes stem cell ads
Actor Michael J Fox appears in campaign ads for US politicians who support stem cell research.
Voting in shadow of stem cell debate
An emotionally-charged debate over stem cell research is overshadowing the US mid-term elections in Missouri, writes the BBC's Matthew Davis.
Visiting the population centre of US
As the number of people living in the US hits 300m, the BBC visits the tiny hamlet known as the "population centre" of America.
