The explosion in uranium mining company stocks this year shows big investors are choosing the nuclear option again. Global X Uranium (URA) -- the No. 1 performing natural resources fund -- spiked nearly 4% Thursday, breaking above its key 200-day moving average for the first time in 10 months. This could be the early beginnings of a trend change for this ETF, which crashed 19% last year and a whopping 60% in 2011 following Japan's nuclear disaster