[The three major U.S. stock indexes collectively closed down. AI computing power leasing companies and optical communications sectors surged.] On September 9, the three major U.S. stock indexes collectively closed down. The Dow Jones Industrial Average fell 1.17%, the Nasdaq fell 0.32%, and the S&P 500 Index fell 0.58%. The optical communications sector surged, with Lumentum rising by more than 11%, Corning rising by more than 7%, and Coherent rising by more than 7%; AI computing power leasing companies rose by more than 11%, and Nebius rose by more than 7%. Intel rose more than 9%, and the company plans to increase PC CPU prices by 10%. Novartis Pharmaceuticals fell more than 13% after suffering its third clinical trial setback in a week.