Harvard University has instituted a total ban on professors having sex with undergraduate students, strengthening language it said didn’t reflect its expectations on appropriate relationships between faculty members and students. Harvard said in a statement released Thursday the change came as part of a formal review of its policy on Title IX, the federal civil rights law prohibiting sex discrimination in education. The Faculty of Arts and Sciences Committee on Sexual Misconduct Policy and Procedures determined the university’s language on “relationships of unequal status” was not strong enough. …