A reveler strikes a pose during an unofficial carnival block party referred to as “blocos”, in Rio de Janeiro, Brazil, Saturday, February 26, 2022. City Hall banned all blocos, the tightly packed street parties attended by those who cannot or don't want to buy pricey tickets for the official parade at the Sambadrome, due to a wave of the Omicron variant. (Photo by Silvia Izquierdo/AP Photo)

Undated handout photo issued by Andrew H Williams/WPR of resident Rosemary Lester at Sherwood Grange care home in Kingston Vale, south west London, focusses her attention during a nude life drawing class. Issue date: Monday July 25, 2022. (Photo by Andrew H Williams/Care UK/PA Wire)

Some runners fall during the “El Pilon” running-the-bulls in the village of Falces, Navarra, northern Spain, 16 August 2022. “El Pilon” running-the-bulls is held on a hill where runners have to avoid the herd of cows on a 800 meter long and narrow slope with the mountain on one side and a steep cliff on the other. (Photo by Peio H/EPA/EFE)

National police transport an anti-government protester detainee during a protest against Nicolas Maduro's government in Caracas March 13, 2014. Venezuela's state prosecutor said on Thursday the death toll from a month of violent protests had risen to 28, after the nation's top court ordered opposition mayors to dismantle barricades set up by street protesters. State prosecutor Luisa Ortega Diaz, speaking on the sidelines of the U.N. Human Rights Council in Geneva, also said 1,293 detainees had been released and 104 remained in custody accused of serious crimes during the anti-government demonstrations. (Photo by Carlos Garcia Rawlins/Reuters)

Netapp Endura team rider Slovenian Blaz Jarc (R) crashes into Katusha team rider Russian Viacheslav Kuznetsov (ground) during the 112th Paris Roubaix cycling race, in Roubaix, France, 13 April 2014. (Photo by Nicolas Bouvy/EPA)

Britain's skip Eve Muirhead, right, embraces Anna Sloan after defeating Switzerland to win the women's curling bronze medal at the 2014 Winter Olympics, Thursday, February 20, 2014, in Sochi, Russia. (Photo by Robert F. Bukaty/AP Photo)

Soldiers take part in a drill during a heavy snow in Heihe, Heilongjiang province, February 26, 2014. (Photo by Reuters/China Daily)

Brain-on-a-chip. Dazzling in green and magenta this image shows the nerve fibres (in green) produced by neural stem cells (in magenta) as they grow on a synthetic gel. Captured by a technique known as confocal microscopy, the image is part of research shedding light on how tinkering with the environment can affect the way in which nerve fibres grow. (Photo by Collin Edington and Iris Lee/Massachusetts Institute of Technology/Wellcome Images)