It is time to get used to near-zero savings-account interest rates and 10-year bond yields that don’t get much higher than 3%. Yes, the Federal Reserve is preparing to raise rates as soon as next spring. Scott Mather, deputy chief investment officer at bond fund manager Pacific Investment Management Corp., which has $2 trillion in assets under management, says the eventual resting point for rates will be much lower and “the Fed will take a lot longer to get there than in previous cycles.