[ by Melanie Gretchen ] One man's loss is another man's gain: this month marks the second time UBS has pried an executive from Bank of America.  Following the departure of 2 top-level bankers from UBS, the Swiss bank hired a prominent banker for the position of vice chairman of UBS Group Americas, after successfully luring away BofA's chairman of global banking and markets at Bank of America. At UBS, James D. Forbes previously ran Global Principal Investments group, the private equity arm of the bank.  Last month, Andrea Orcel, the chairman of global banking and markets at Bank of America, was named co-head of investment banking at UBS. In his new position, Mr. Forbes will focus on building health care and financial clients, as well as aiding certain businesses across the investment bank and within the United States.  He previously worked with Bob McCann, chief executive of UBS Group Americas, at Merrill Lynch.  There, Mr. Forbes helped lead Merrill’s global health-care investment banking business before its merger with Bank of America.  More recently, at Bank of America’s private equity unit, Mr. Forbes oversaw the firm’s stake in the China Construction Bank, which has been gradually whittled down. The top-level bankers leaving UBS include the firm's head of investment banking for the Americas, Aryeh Bourkoff, who resigned to "pursue other opportunities."  A day later, a co-head of mergers and acquisitions in the United States, Ehren Stenzler, left the firm. For further details, go to [Dealbook, 4/23/12].