The Dow Jones Industrial Average closed down 307.16 points amid concerns over tensions in the Middle East, while investors await earnings reports from major technology companies this week. The Dow ended at 51,839.26, down 0.59%. The S&P 500 closed at 7,443.28, down 0.19%, and the Nasdaq finished at 25,508.07, down 0.05%. Eight of the 11 S&P 500 sectors ended in negative territory, led by healthcare which fell 1.15%, while a rebound in chip stocks helped partially support the Nasdaq.