Facebook also looks to be testing the quality, size and positioning of images on the news feed, which was just redesigned this week.

FORBES: Google+ Gets A Jump On Facebook

Mr Mahdavi says his technique could control the size and positioning of the bubbles in such foam, and so determine the material's strength and rigidity.

ECONOMIST: MONITOR

Mr. Ferguson said he is confident Cadillac new lineup can take on the Germans by more directly positioning its cars in the same size and price categories of the German brands.

WSJ: Can the New Cadillac CTS Catch Up to BMW?