Asian stocks turned in a mixed performance on Wednesday as talks between the U.S. and Iran faced new hurdles, fueling inflation worries and increasing the likelihood of Federal Reserve interest-rate hikes. Iran's chief negotiator said Iran will not enter negotiations on a final agreement unless five preliminary conditions are met, including lifting the U.S. naval blockade and releasing frozen Iranian assets. The U.S. dollar gained on a sharp rise in Treasury yields, while gold fell more than 1 percent to $3,964 an ounce after Cleveland Fed President Beth Hammack warned inflation is still too high. China's Shanghai Composite rose 0.44 percent to 4,112.45 after a private survey showed the manufacturing sector capped its strongest quarter in almost six years, while Japan's Nikkei average advanced 0.59 percent to 70,474.96 as the yen slid to a fresh 40-year low. Seoul's Kospi tumbled 2.04 percent to 8,303.41 on profit-taking in semiconductor shares, and Australia's S&P/ASX 200 dropped 0.64 percent to 8,722.90.