MALE STUDENT: No wonder featherwork was a symbol of high status in ancient Peruvian societies.

FEMALE PROFESSOR: Well, that's definitely a long, dangerous trip to make on foot.I do research down in Peru and I've made that trip, but the easy way-I've flown and driven.

MALE STUDENT: I didn't know you did research in Peru.Maybe- do you think you'd be able to help me with this paper?

请问老师，这里的down的用法，以及research是名词还是动词？