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)

People make their way on an algae-covered beach in Qingdao, Shandong province, China, July 19, 2015. (Photo by Reuters/Stringer)

The homemade Airbus A320 jet plane made by Chinese farmer Zhu Yue is being built at an open space in Kaiyuan city, northeast China's Liaoning province on February 4, 2018. (Photo by Imaginechina/Rex Features/Shutterstock)

Kim Kardashian is seen on February 15, 2017 in New York City. (Photo by Team GT/GC Images)

A man wearing a costume dives into a partly frozen lake in Shenyang, in China's northeastern Liaoning province on February 19, 2019. (Photo by AFP Photo/China Stringer Network)

In this April 18, 2019 photo, tattoo artist Lalo Calva inks a tattoo on client Adrian Alonso Rodriguez, a journalist, announcer and dubbing artist, at the Corona Tattoo parlor in Mexico City. Not only inks and techniques have changed in Mexico over the years, but tattoos themselves have evolved from stigmatized symbols of gangs, violence and poverty to an art form. (Photo by Marco Ugarte/AP Photo)

Hundreds of students take part in the traditional Raisin Monday foam fight on St Salvator’s Lower College Lawn in Scotland on October 21, 2019. The messy display is the culmination of a weekend of festivities where first years say thank you to their more senior student “parents” for mentoring them. (Photo by Jane Barlow/PA Images via Getty Images)

Base jumpers leap from the 300-metre high skydeck of Malaysia's landmark Kuala Lumpur Tower against the backdrop of the city's skyline in Kuala Lumpur on September 30, 2018 during the annual International KL Tower Base-Jump event. (Photo by Manan Vatsyayana/AFP Photo)