The list of U.S. companies announcing lower second-quarter earnings keeps getting longer. Some heavyweights are included among the corporate victims of a slower U.S. economy, and it goes beyond the U.S. borders. On Friday, Nortel Networks of Canada, the world's leading supplier of telecom equipment, said it would take a big loss and plans to cut more jobs. Meanwhile, U.S. manufacturing slumped in May for an eighth consecutive month. And businesses are cutting prices in the face of slower demand.