Russian Mi-28N from the Berkuty (Golden Eagles) helicopter display team fly in formation during the “Aviadarts” military aviation competition at the Dubrovichi range near Ryazan, Russia, August 2, 2015. The aircraft started dipping down due to back propeller failure and crashed, killing one of two pilots, according to a Reuters photographer and official representatives of the competition. The aviation contest is part of the International Army Games, which are held in Russia from the 1st till the 15th of August with participants from 17 countries, according to organizers. (Photo by Maxim Shemetov/Reuters)

Serge Huguenin of the Blondeau foundry takes the newly melted bell out of the mould in La Chaux-de-Fonds, Switzerland January 21, 2016. At this year's Summer Olympics in Rio de Janeiro, no matter how elaborate the opening ceremony or how sophisticated the live broadcasts, the final lap of athletics races will be announced the traditional way by ringing an old-fashioned bell. Omega, the official timekeeper of the event, has ordered 21 bells, forged almost entirely by hand by Blondeau's Bell Foundry in the Jura Mountains in Switzerland. Each last-lap bell is branded with the RIO 2016 logo and circled with the words “2016 GAMES OF THE XXXI OLYMPIAD”. (Photo by Denis Balibouse/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)

Director Taro Kambe directs as he watches acting with VR headset during a rehearsal for ROCKET's 3D virtual reality adult film at the company's studio in Tokyo, Japan, July 31, 2017. Japan is the world's second biggest virtual reality market after the United States and the adult entertainment industry and gaming sector are turning to VR as a new way to distribute content. (Photo by Kim Kyung-Hoon/Reuters)

This picture taken on October 20, 2016 shows students practising wushu at the Tagou martial arts school in Dengfeng. China is investing hugely in football training and has vowed to have 50 million school- age players by 2020, as the ruling Communist party eyes “football superpower” status by 2050. (Photo by Nicolas Asfouri/AFP Photo)

This 1931 Stutz DV-32 convertible sedan has 66,000 miles on its odometer and its original leather luggage awaits its first complete restoration Tuesday, March 5, 2013 at L'Cars Automotive Specialties in Cameron, Wis. The company which does high-end restoration and customization work classic cars that have won awards at the world-renowned Pebble Beach Concours d'Elegance. Winning cars include a 57c Bugatti, Rolls Royce PIII V12, V12 Aero coupe, T44 Bugatti, T55 Bugatti, T38A Bugatti, Mercedes Benz 290 Roadster, Rolls Royce Silver Ghost, T57 Bugatti, 1929 Duesenberg J, Mercedes Benz 540K cabriolet, Talbot Teardrop and a 1931 V16 Cadillac convertible. (Photo by Mark Hoffman)

A horse trainer takes his horse into the water at Pebble Beach on June 28, 2024 in Bridgetown, Barbados. The swimming horses of Barbados offer a unique and remarkable experience at Pebbles Beach, where racehorses from the nearby Garrison Savannah enjoy their morning swim almost daily between 5:30 am and 7 am. During this ritual, horses swim out surprisingly far to the moored boats before returning to shore, with some staying longer in the water if recovering from injury or soreness after a race. Visitors can observe the horses' individual personalities as they swim and interact with the water, but are advised to respect the guidance of the grooms and maintain a safe distance, as horses can behave unpredictably, especially if frightened. (Photo by Robert Cianflone/Getty Images)

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)