NEW YORK :U.S. stocks weakened and benchmark Treasury yields inched lower as investors embarked on a week of accelerated economic data releases in the aftermath of the longest government shutdown in United States history. Chipmaker Nvidia is due to report quarterly earnings on Wednesday, and the artificial intelligence bellwether's results will be scrutinized for signs of waning demand in the sector that has driven much of the stock market's rally over recent months. All three major U.S. stock