Brazilian-born financier Leda Braga, former president and head of systematic trading at BlueCrest Capital Management, turned heads in late 2014 when she announced she was leaving the London hedge fund firm after 13 years to found Geneva-based Systematica Investments. Braga spun commodity trading adviser BlueTrend and other computer-driven trend-following hedge funds, including BlueMatrix, out of BlueCrest, taking the management team and clients with her. BlueTrend lost 11.4 percent in 2013, a tough year for computer-driven hedge funds, only to return 12.7 percent the following year…