A federal minimum wage increase that takes effect Friday could prolong the U.S. recession, some economists say, by forcing small businesses to lay off the same workers that the pay hike passed in better times was meant to help, dpa reported. The increase to $7.25 means 70 cents more an hour for the lowest-paid workers in the 30 states that don't have a higher minimum. It also means higher costs for employers who feel they've already trimmed all their operating fat.