NEW YORK--(BUSINESS WIRE)--Global investors have raised their holdings of cash significantly in response to a weaker global economic outlook, particularly in China, according to the BofA Merrill Lynch Fund Manager Survey for July. Overall, equity allocations are unaffected by the higher risk aversion, however. Confidence in the global economy falls sharply: 42 percent of investors expect strengthening over next year, down from 55 percent a month ago. China heads concerns: net 62 percent expect