(Reuters) -Federal Reserve policymakers on Tuesday promised further rapid interest-rate hikes to bring down high inflation, but pushed back against growing fears among investors and economists that sharply higher borrowing costs will trigger a steep downturn. “Many are worried that the Fed might be acting too aggressively and maybe tip the economy into recession,” San Francisco Fed President Mary Daly said in an interview on LinkedIn. “I am myself worried that left unbridled, inflation would be a major constraint and threat to the U.S economy and continued expansion.” The Fed, she said, is the…