This week Sears Holdings announced it would shutter another 50 unprofitable Sears and Kmart stores across the country. This follows several previous rounds of store closings for the once-mighty chain, whose equity now is said to lie primarily in the value of its real estate holdings. But Sears says the closings will not affect its Bethesda location at Westfield Montgomery Mall. “That store will remain open,” company spokesman Howard Riefs told us this week.