Pedestrians cover their face as they walk along the dusty road in Kathmandu, Nepal February 27, 2017. Nepal has forced 2,500 old vehicles off roads in its capital city of Kathmandu, part of a fight against alarming air pollution levels that have hit nine times World Health Organisation (WHO) limits. Air pollution has been a chronic problem in rapidly growing Kathmandu, which sits in a Himalayan valley and is home to more than 3mn people. (Photo by Navesh Chitrakar/Reuters)

A patient solves a rubik's cube at a temporary hospital converted from “Wuhan Livingroom” in central China's Hubei Province on February 10, 2020. In face of the outbreak of the novel coronavirus pneumonia epidemic, Wuhan authorities have transformed public venues such as exhibition centers and gymnasiums into temporary hospitals. The hospitals have a large capacity of treating patients with mild symptoms and play an important role in isolating the source of infection and cutting off the routes of infection during epidemic prevention. The first batch of patients was hospitalized on Feb. 5. (Photo by Chine Nouvelle/SIPA Press/Rex Features/Shutterstock)

Models dressed as showgirls participates in a fashion show in front of the Welcome to Fabulous Las Vegas sign on the Las Vegas Strip to kick off the pro-mask wearing campaign “Mask Up for Nevada” put on by Experience Strategy Associates amid the spread of the coronavirus on June 25, 2020 in Las Vegas, Nevada. On Wednesday, Nevada Gov. Steve Sisolak signed a directive requiring people to wear face coverings in public places throughout the state beginning on June 26 in response to a four-week upward trend of new daily COVID-19 cases. (Photo by David Becker/Zuma Press)

Workers collect fish inside an abandoned department store in Bangkok, Thailand January 13, 2015. Staff from Bangkok Metropolitan Administration (BMA) office were catching fish on Tuesday at the ground floor of the roofless New World department store that was closed down in 1997. Thousands of fish such as catfishes, fancy carps as well as black and red tilapias were released into the ground floor of the building, flooded with rainwater, as local vendors tried to control mosquitoes in the area, local media reported. BMA recently decided to remove the fish and release the water. (Photo by Chaiwat Subprasom/Reuters)

Paris Photo is the largest international art fair dedicated to the photographic medium and is held each November at the historic Grand Palais in Paris, France on November 7, 2018. Since 1997, the Fair’s mission is to promote and nurture photographic creation and the galleries, publishers and artists at its source. The 22nd edition of Paris Photo will takes place Thursday, November 8 through Sunday, November 11. (Photo by IBO/SIPA Press/Rex Features/Shutterstock)

A female Marine prepares to throw a practice grenade during Marine Combat Training (MCT) on February 21, 2013 at Camp Lejeune, North Carolina. Since 1988 all non-infantry enlisted male Marines have been required to complete 29 days of basic combat skills training at MCT after graduating from boot camp. MCT has been required for all enlisted female Marines since 1997. About six percent of enlisted Marines are female. (Photo by Scott Olson)