NEW YORK (AP) — A look at the 10 biggest percentage gainers on Nasdaq at 1 p.m.:

Atossa Genetics rose 15.2 percent to $7.67.

Ikonics Corp. rose 13.2 percent to $14.48.

Clayton Williams Energy Inc. rose 10.6 percent to $46.25.

Northwest Pipe Co. rose 10.0 percent to $27.00.

China Natural Resources Inc. rose 8.2 percent to $5.25.

YRC Worldwide Inc. rose 7.8 percent to $7.63.

Chindex International Inc. rose 7.6 percent to $13.09.

Microfinancial Inc. rose 7.3 percent to $8.47.

Groupon Inc. rose 6.9 percent to $5.43.

Obagi Medical Products Inc. rose 6.7 percent to $14.88.