U.S. economic activity picked up in recent weeks as a weather-related drag lifted, the Federal Reserve said on Wednesday. In its Beige Book report of anecdotal information on business activity collected from contacts nationwide, the U.S. central bank said eight of its 12 districts characterized growth as “modest to moderate.” Chicago reported that growth had picked up, while New York and Philadelphia said activity had rebounded from slowdowns related to severe weather earlier in the year.