The Base Realignment and Closure Commission will hear testimony today in Boston from Maine and New Hampshire officials, including Maine’s congressional delegation and Gov. John Baldacci. Portsmouth Naval Shipyard and the Defense Finance and Accounting Service center at Limestone are on the closure list. The Brunswick Naval Air Station is on the realignment list and would lose some aircraft and half of its personnel. The Save Our Shipyard Association has rented a fleet of buses to take supporters to Boston from Portsmouth, N.H., and Kittery. Other buses will take supporters from Topsham.