 stocks are trying to hold on to small gains in afternoon trading as Wall Street kicks off the first day of trading for the new month and second half of the year. MegaCap tech stocks are mixed after notching a blockbuster first half of the year, and shares of AI darling Nvidia are wavering after choppy trading last week. Industrials are among the laggards today, and U.S. manufacturing contracted for a third straight month in June, and a measure of prices paid by factories for inputs dropped to a six-month low due to weak demand for goods,