Palestinian girls take part in a ballet dancing course, run by the Al-Qattan Center for Children, in Gaza City November 25, 2015. (Photo by Suhaib Salem/Reuters)

Artist Kong Ning wears a wedding dress made from respirators to highlight concerns about air quality and pollution in Beijing, China on December 1, 2015. (Photo by Luo Xiaoguang/Xinhua Press/Corbis)

People take part in the "Bison Race" winter extreme run competition in Zhodino, Belarus, December 5, 2015. (Photo by Vasily Fedosenko/Reuters)

Participants run through the streets of the Back Bay during the 16th annual Santa Speedo Run in Boston, Massachusetts, December 12, 2015. (Photo by Brian Snyder/Reuters)

Somali men carry swordfish from the sea to a market in the capital Mogadishu, Somalia Thursday, April 23, 2015. (Photo by Farah Abdi Warsameh/AP Photo)

Cracks are seen on one of the shrines at Swoyambhunath Stupa, a UNESCO world heritage site, after Saturday's earthquake in Kathmandu, Nepal April 28, 2015. (Photo by Navesh Chitrakar/Reuters)

General view of the entrance to the Swarowski Crystal World museum on its reopening day following renovation, in the western Austrian village of Wattens April 30, 2015. (Photo by Dominic Ebenbichler/Reuters)

Sumo wrestlers of Nishonoseki clan appeal to the winner of a training bout for the next opponent during a joint training session ahead of the May Grand Sumo Tournament in Tokyo May 2, 2015. (Photo by Toru Hanai/Reuters)