Boston's 'Mass and Cass' area, with its large homeless population and open-air drug market, remains a trouble spot for city officials, but staff at the nearby Engagement Center say they are making inroads and helping drug-overdose survivors get the help they need. Researchers interviewed 59 overdose survivors, more than half of whom were living on the street, to find out what was preventing them from getting treatment. Jeff Desmarais, research and evaluation scientist at Institute for Community Health, said a lack of basic amenities, such as housing and access to a cell phone or proper ID, made a big difference, but that it also came down to a personal touch. ...