Russian cybersecurity firm, Kaspersky Lab, has told workers in its U.S.-based division that they are being laid off this week and that it is closing its U.S. business, according to several sources. The sudden move comes after the U.S. Commerce Department announced last month that it was banning the sale of Kaspersky software in the U.S. beginning July 20. The company has been selling its software here since 2005.Kaspersky confirmed the news to Zero Day, saying that beginning July 20 it will "gra...