A business that got its start overhauling military Humvees and trucks is preparing to slash its workforce by more than half because of reduced demand. Maine Military Authority said Friday that it intends to cut 140 jobs beginning in October because of the drawdown of troops and equipment in Iraq and Afghanistan. MMA currently employs 210 workers. CEO Tim Corbett says the company will do everything it can to minimize layoffs. That includes expanding into the refurbishment of transit buses in the state. Created in 1997, the Maine Military Authority, a quasi-state agency, has refurbished more than 14,000 military vehicles at the former Loring Air Force Base in Limestone.