PROVIDENCE, R.I. — Claudio Neves Valente, a man linked to a mass shooting at Brown University, was found dead from a self-inflicted gunshot wound in New Hampshire. The 48-year-old immigrant from Portugal also stands accused of killing his former classmate, Nuno F.G. Loureiro, an MIT professor, just days after the Brown shooting, where two students were fatally shot and nine others injured. Neves Valente’s academic history included a time at Brown as a graduate student where he withdrew without completing his degree. The investigations into his motives continue, leaving many unanswered questions about this disturbing series of events.