Also . . .

* Union Pacific vowed to make “very substantial improvement” within 30 days in the nation’s massive railroad freight traffic jam. The rail company told federal regulators it may resort to a temporary ban on new freight from its system or transfer business to its competitors.

* A year after debuting her home furnishings line at Kmart stores, Martha Stewart is expanding the line with about 600 products, including bathroom accessories. Kmart said the Stewart products have attracted new customers to the discount retailer and accounted for $500 million in sales last year.