Thai Prime Minister Yingluck Shinawatra walks at a polling station after casting her ballot in Bangkok March 30, 2014. Thais voted on Sunday for half of the country's 150-seat Senate in a key test for Yingluck's troubled government, a day before the prime minister is due to defend herself against negligence charges over a disastrous rice subsidy scheme. REUTERS/Chaiwat Subprasom (THAILAND - Tags: POLITICS ELECTIONS CIVIL UNREST TPX IMAGES OF THE DAY)