Team Strong Silvers member Ngai Hin Kwok, 66, works out as teammate Ng Siu Chi, 57, watches at a stadium in Singapore March 15, 2015. Team Strong Silvers, is a group of senior citizens who train in calisthenics. The trio trains individually at least three times a week, and meets up for joint calisthenics at least twice a month. (Photo by Edgar Su/Reuters)

Turkish artist Nezaket Ekici performs a live art performance entitled 'Emotion in Motion' on the first day of Art Basel 2015, Hong Kong, China, 13 March 2015. The Hong Kong show of Art Basel features 233 galleries from 37 countries and territories, presenting works ranging from the Modern period of the early 20th century to the most contemporary artists of today, according to the official press release. (Photo by Alex Hofford/EPA)

Shi'ite fighters launch a rocket during clashes with Islamic State militants on the outskirts of al-Alam March 8, 2015. Thaier Al-Sudani: “It was me and a few other Iraqi journalists working for local outlets. We went to the frontlines in coordination with the Iraqi government forces and supporting militias. The press officer would come in the morning and take us to the frontline in a convoy. Whenever an area was won from Islamic State, the fighters would chant and pray and show victory signs. Most of the areas we were in didn't have residents, so after the battle they would resemble ghost towns; nothing but burnt cars and charred bodies of Islamic State fighters. Al-Alam was an exception as it had some residents who chanted for the government forces after their victory”. (Photo by Thaier Al-Sudani/Reuters)

In this February 2, 2015 photo, tourists jump as they pose for a picture, after disembarking from the Ocean Nova cruise ship, on King George Island, Antarctica. This tourist season, which runs November through March, more than 37,000 visitors are expected to walk on the coldest continent on Earth, about 10 percent more than the year before. (Photo by Natacha Pisarenko/AP Photo)

Members of the Legio X Fretensis (Malta) re-enactment group take part in a display of ancient Roman army life at Fort Rinella in Kalkara, outside Valletta, March 22, 2015. The event “Romanus”, organised by the Malta Heritage Trust, consisted of talks, hands-on displays, static exhibitions of weapons and equipment, food and wine tasting and large-scale re-enactments depicting different forms of Roman warfare in the field. (Photo by Darrin Zammit Lupi/Reuters)

Vultures gather to eat waste in Bica beach, on the banks of the Guanabara Bay, with the Sugar Loaf mountain in background, 500 days ahead the Rio 2016 Olympic Games in Rio de Janeiro March 24, 2015. As part of its Olympic bid, Rio promised to clean up 80 percent of the bay for the games. But local government officials have already admitted that a cleanup by 2016 is not achievable. Despite millions of dollars of investment over the years, the bay still stinks of sewage. Sailors who visited the city for test events complained of a floating sofa and a dead dog in the water. (Photo by Ricardo Moraes/Reuters)

In this Tuesday, March 31, 2015 photo, Indian women walk carrying firewood they collected from a forest at Gobhali village on the outskirts of Gauhati, India. Every evening, hundreds of millions of Indian women hover over crude stoves making dinner for their families. They feed the flames with polluting fuels like kerosene or cow dung, and breathe the acrid smoke wafting from the fires. (Photo by Anupam Nath/AP Photo)

In this Monday, March 16, 2015 photo, Syrian refugee Samira Helal, 17, who is two months pregnant, poses for a portrait at inside her tent at an informal tented settlement near the Syrian border, on the outskirts of Mafraq, Jordan. Nearly 3.8 million Syrians have fled their country and are now registered as refugees, according to the U.N. Most face increasingly desperate circumstances. (Photo by Muhammed Muheisen/AP Photo)