GLOBAL MARKETS-U.S. rate hike prospects lift dollar, Treasury yields

* Dollar gains on Fed rate hike hopes, data * U.S. Treasury yields mostly up * Dollar pushes commodities to near six-year lows By Michael Connor NEW YORK, July 30 (Reuters) - The dollar traded at one-week highs and shorter-term U.S. Treasury yields rose on Thursday as accelerating U.S. gross domestic product data encouraged bets that policymakers will start hiking U.S. interest rates as soon as September. Wall Street was mostly lower in part due to soft corporate earnings re