Treasuries posted narrow losses Thursday, but the 30-year bond advanced after the Treasury's third auction of the week successfully drew investors to the government's longest-term security. The government's sale of $13 billion in 30-year bonds concluded a series of well-bid auctions totaling $74 billion, muffling concerns about a sated appetite for U.S. debt. "This week's auctions show there is investor interest for bonds around the 3.75% 10-year