INSIDE HIGHER ED — Monday was the start of Welcome Week at American University. Students and parents arriving at the Washington, D.C., campus were greeted not only by smiling university ambassadors but also a picket line of more than 100 members of the university’s staff union, gathered for the first day of a weeklong strike. The strike, announced Aug. 11, was approved by 91 percent of the union, which represents over 500 professional staff members in a wide range of positions.