People leave a giant air purifier, which its inventor calls a “super tree”, in Lima's district of Jesus Maria November 24, 2014. In Peru's notoriously polluted capital Lima, local inventor Jorge Gutierrez, a retired naval engineer, is deploying the giant air purifiers that double as billboards to suck up carbon dioxide and dangerous levels of smog. (Photo by Mariana Bazo/Reuters)

Chinese aids activists hand out condoms in a subway train in Wuhan, central China's Hubei province on December 1, 2014. The World Health Organization issued a call to action to China on December 1, 2014 over HIV/AIDS as government figures said nearly half a million people are living with the disease or its precursor, with hundreds of thousands more thought to be undiagnosed. (Photo by AFP Photo)

A man stands at a passenger train damaged in a collision with a freight train in Moscow region May 20, 2014. The passenger train on its way to Moldova collided with a freight train near Moscow on Tuesday, killing at least four people and injuring 15, a spokeswoman for Russia's Emergencies Ministry said. The reason for the collision, near the town of Naro-Fominsk 55 km (34 miles) southwest of Moscow, was not immediately clear. (Photo by Grigory Dukor/Reuters)

Students receive a group punishment during a military-style close-order drill class at the Qide Education Center in Beijing February 19, 2014. The Qide Education Center is a military-style boot camp which offers treatment for internet addiction. As growing numbers of young people in China immerse themselves in the cyber world, spending hours playing games online, worried parents are increasingly turning to boot camps to crush addiction. Military-style boot camps, designed to wean young people off their addiction to the internet, number as many as 250 in China alone. (Photo by Kim Kyung-Hoon/Reuters)

This picture taken on July 15, 2014 shows a bridge submerged in floodwaters in the ancient town of Fenghuang, central China's Hunan province. Rainstorms lashed central China's Hunan Province and southwest China's Guizhou Province, affecting over 1 million people and flooding a historical town, state media reported. (Photo by AFP Photo)

Soldiers use electronic sensors to search for missing firefighters under a line of fire trucks caught in massive gas explosions in Kaohsiung, Taiwan, Friday, August 1, 2014. A series of underground explosions about midnight Thursday and early Friday ripped through Taiwan's second-largest city, killing scores of people, Taiwan's National Fire Agency said Friday. (Photo by Wally Santana/AP Photo)

NYC no pants subway ride. Thousands of straphangers took their pants off for the 15th annual "No Pants Subway Ride" hosted by Improv Everywhere. People gathered at seven meeting points throughout the five boroughs at 3PM. All participants met up at Union Square around 5PM to and had a pant-less celebration and the afterparty at Webster Hall. (Photo by Paul Martinka/The New York Post)

Anton Unitsyn, Russia. Shortlist, Professional , Daily Life. Parkour jumpers on their daily training. On the background – one of the main Solvychegodsk sights – Blagoveshchensky Cathedral. This church is among 3 churches, that survived soviet times. At the begining of 20th century there were 13 churches in Solvichegodsk. After breakdown of the communism, Solvichegodsk as many small towns in russia is stuck in it's past. Despite everything, people in Solvichegodsk still belive in their positive future, and wait for wind of change. (Photo by Anton Unitsyn/Sony World Photography Awards)