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)

Aceh Ulema Council (MPU) member Mukhlis reacts as he is whipped in public by a member of the Sharia police in Banda Aceh on October 31, 2019. An Indonesian man working for an organisation which helped draft strict religious laws ordering adulterers to be flogged was himself publically whipped on October 31 after he was caught having an affair with a married woman. (Photo by Chaideer Mahyuddin/AFP Photo)

Norma Galicia aka “Pirulina” takes part in a demonstration during the commemoration of the International Day for the Elimination of Violence Against Women, in Guatemala City on November 25, 2013. So far this year, 696 women have died due to violent events in Guatemala. (Photo by Johan Ordonez/AFP Photo)

A model presents a creation from Lino Villaventura Summer 2016 Ready To Wear collection during Sao Paulo Fashion Week in Sao Paulo April 16, 2015. (Photo by Paulo Whitaker/Reuters)

Participants of the the goth festival “Wave Gothic Festival” walk in fancy costumes along the festival area in Leipzig, central Germany, Saturday, May 23, 2015. About 20,000 members of the scene are expected to attend one of the world's largest gothic and “dark” culture festivals until May 25, 2015. (Photo by Jens Meyer/AP Photo)

Young female Ibex on the fork of Disteis (2,200 m), near the top of the Jof di Montasio (Friuli, Italy). (Photo by Stefano Zocca)

A groom leads his horse in the equine pool after working out on the track, during early morning workouts for the upcoming Derby race in Mumbai January 29, 2015. (Photo by Danish Siddiqui/Reuters)

Employees of a food stand take pictures of Titan, a robot created by England Cyberstein Robots, performing at the Danilovsly market in downtown of Moscow, Russia, 12 May 2014. Titan visited to Moscow to attend “Bal Robotov”, an interactive exhibition of the most recent advances in robotics which will be opened on 15 May in Artplay Moscow exhibition center. Titan worked alongside superstars including Will.i.am, Rihanna, Will Smith and Jackie Chan. (Photo by Sergei Ilnitsky/EPA)