A performer from the Academicos do Grande Rio samba school dances during carnival celebrations at the Sambadrome in Rio de Janeiro, Brazil, early Monday, February 16, 2015. (Photo by Silvia Izquierdo/AP Photo)

A Ukrainian serviceman who fought in Debaltseve is seen near Artemivsk February 19, 2015. Fighting raged in eastern Ukraine on Thursday despite European efforts to resurrect a still-born ceasefire, a day after pro-Russian separatists who spurned the truce forced thousands of government troops out of a strategic town. (Photo by Gleb Garanich/Reuters)

Ana Ivanovic of Serbia plays a backhand return to Maria Sharapova of Russia during their women's singles final match at the Brisbane International tennis tournament in Brisbane, January 10, 2015. (Photo by Jason Reed/Reuters)

Jessica Chastain arrives at the 72nd annual Golden Globe Awards at the Beverly Hilton Hotel on Sunday, January 11, 2015, in Beverly Hills, Calif. (Photo by Jordan Strauss/Invision/AP Photo)

Iraqi security forces take part in training, as they prepare to fight against militants of the Islamic State, at a training camp on the outskirts of Mosul January 10, 2015. (Photo by Azad Lashkari/Reuters)

Soldiers stop to buy goods at the main market of Diffa, Niger, March 23, 2015. Diffa is where Nigerien and Chadian troops fighting insurgent group Boko Haram are based at. (Photo by Joe Penney/Reuters)

A masked reveller poses near Saint Mark's Square during the Venetian Carnival in Venice January 31, 2015. (Photo by Stefano Rellandini/Reuters)