TEXT: "Yahoo CEO Marissa Mayer gestures before the session ""In Tech We Trust"" in the Swiss mountain resort of Davos January 22, 2015. More than 1,500 business leaders and 40 heads of state or government attend the Jan. 21-24 meeting of the World Economic Forum (WEF) to network and discuss big themes, from the price of oil to the future of the Internet. This year they are meeting in the midst of upheaval, with security forces on heightened alert after attacks in Paris, the European Central Bank considering a radical government bond-buying programme and the safe-haven Swiss franc rocketing.                                          REUTERS/Ruben Sprich (SWITZERLAND  - Tags: BUSINESS POLITICS)"