By John S. McClenahen Initial claims for unemployment insurance rose by 10,000 last week to a seasonally adjusted figure of 343,000, the U.S. Labor Department reported on Aug. 26. Economists generally were looking for a figure of 330,000 to 335,000. The department's four-week moving average for claims, however, fell to 336,750, some 750 less than the previous week's revised average of 337,500. The latest claims statistics probably reflect an increase in job layoffs in the wake of Hurricane Charley, which hit Florida two weeks ago. Prior to the release of yesterday's data, UBS Investment Research was putting the number at 10,000. But UBS added, "The effect of the hurricane [on the numbers] should fade within a couple of weeks."