YAMEL MERINO, 24, of Yonkers, N.Y., an emergency medical technician with Metro Care Ambulance, was helping the injured near the World Trade Center when the first tower collapsed, killing her. Steve Zakhein, chief operating officer of the ambulance company, said Merino was “one of the heroes of our city.” He said she won the company’s “EMT of the Year” award in 1999. Jim O'Connor, a friend and colleague, said, “When a textbook says, ‘This is the perfect EMT,’ that’s what Yamel was.”