Complex sentence: From 1976 to 1981, Nemtsov studied physics at N. I. Lobachevsky State University of Nizhny Novgorod, where in 1985, aged 25, he defended a PhD in Physics and Mathematics.
Split into simpler sentences: From 1976 to 1981, Nemtsov studied physics at N. I. Lobachevsky State University of Nizhny Novgorod. In 1985, at age 25, he defended a PhD in Physics and Mathematics.