An abandoned state mental health facility in Boston’s prestigious Longwood Medical Area is being transformed into the Mass Mental Health Center, a four-building mixed-use complex that includes a mental health day hospital, a clinical and office building, a medical research facility for Brigham and Women’s Hospital, and a residential facility. Construction began in 2010 on the mental health day hospital and the clinical and office building, while construction on the housing component is scheduled to begin in 2013. Work on the research facility will begin sometime after that. The MMHC is being planned and designed by The Architectural Team, Chelsea, Mass., in association with Linea 5 Inc., Boston. John Moriarty & Associates, Winchester, Mass., is the GC.