Opposition students march against Venezuelan President Nicolas Maduro's government in Caracas February 12, 2015. Venezuelan troops blocked students during marches against Maduro on Thursday as pro-government supporters also rallied on the anniversary of 2014 protests that led to 43 deaths. In Caracas, troops cordoned off scores of students on an unauthorized march to a church where they planned a mass in honour of demonstrators who died. (Photo by Jorge Silva/Reuters)

A shop assistant creates a window display in a Next store in central London December 30, 2014. British clothing retailer Next's sales rose 2.9 percent in the run up to Christmas mostly due to online and catalogue purchases, hitting the upper end of its predictions and it said full-year profit would rise by about 11.5 percent. (Photo by Neil Hall/Reuters)

Makoto Chino eats a purple haze carrot as he works harvesting the morning's vegetables and fruit from his family's farm in Rancho Santa Fe, California August 12, 2014. The gravitational pull of Chino Farm is legendary. Since they don't ship, everyone – whether a top chef or a traveling foodie or a local resident – comes to the farm stand, simply called “Vegetable Shop”, on a dusty corner of this affluent San Diego County town, hemmed in by sprawling housing estates. (Photo by Mike Blake/Reuters)

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)

A policewoman tries to stop an anti-Occupy protester from breaking a police cordon to charge at pro-democracy protesters during a confrontation in Hong Kong October 13, 2014. Hundreds of unidentified people, some wearing masks, tried to break down protest barriers in the heart of Hong Kong's business district on Monday, scuffling with protesters who have occupied the streets for the past two weeks. (Photo by Bobby Yip/Reuters)

Filipino typhoon victims walk through heavy mud in the typhoon hit town of Taft, Samar island, Philippines, 08 December 2014. Typhoon Hagupit weakened into a tropical storm as it moved towards the Philippine capital after killing at least 27 people and displacing more than one million people in the eastern and central provinces. Hagupit slammed into the country's eastern coast on 06 December evening, bringing heavy rains and gale-force winds that flattened homes, ripped off roofs, and knocked out power and communications. (Photo by Francis R. Malasig/EPA)

A boy pushes a donkey cart loaded with bundles of cotton blooms that were collected by women cotton pickers in Meeran Pur village, north of Karachi September 25, 2014. Women make up the bulk of Pakistan's half a million cotton producers, but labour rights activists say they are often exploited by overseers, who often withhold their wages and may subject some of them to sexual harassment. (Photo by Akhtar Soomro/Reuters)

A woman attends a boxing class at Princess Women's Boxing Club in Shanghai December 3, 2014. Women have boxed as long as the sport has existed but for years they were relegated out of national and international competitions in many countries around the world. Female boxers entered the ring in an exhibition match at the 1904 Olympic Games, but it was more than a century later when they were given the green light to make their Olympic debut in London in 2012. (Photo by Carlos Barria/Reuters)