It can take up to four working days to test a single sample at a laboratory.

BBC: Wales

From a single sample, it is impossible to be certain.

ECONOMIST: Paleoforensic science

Researchers took a single urine sample from hospitalized heart patients, found normal BPA trace amounts, and concluded BPA did it.

FORBES: How Junk Science Distorts What We Read, And The Way We're Governed

"In the past we could spend an hour searching the entire freezer for a single tube, and now we can find a sample within just a few minutes, " he says.

FORBES: The DNA Bar Code

In a single track, Gillis will sample everyone from Mims and Diana Ross to The Carpenters and Metallica, all on top of each other.

NPR: Girl Talk Chops Pop Music To Pieces

Some 25, 000 users in their sample identify themselves as single, versus 19, 000 married and 12, 000 in a relationship.

CNN: Google+ users are nearly all male