Participants run through coloured powder during the YARKOcross colour run race in Almaty, Kazakhstan, June 5, 2016. (Photo by Shamil Zhumatov/Reuters)

Fallon Taylor of Collinsville, Texas, slips and falls with her horse in the barrel racing event during the Calgary Stampede rodeo in Calgary, Alberta, Canada July 8, 2016. (Photo by Todd Korol/Reuters)

Gymnast Ahmad al-Sawas performs gymnastic moves near damaged buildings in the rebel-held Bustan al-Qasr neighbourhood of Aleppo, Syria March 26, 2016. As Syrian gymnast Ahmad al-Sawas watched his country fall apart, his Olympic dream collapsed too. The last national champion before the fighting began, he knew that supporting the anti-government side in the five-year-old civil war would prevent him from being selected for the Rio Games. (Photo by Abdalrhman Ismail/Reuters)

A Syria Democratic Forces (SDF) fighter comforts a civilian who was evacuated with others by the SDF from an Islamic State-controlled neighbourhood of Manbij, in Aleppo Governorate, Syria, August 12, 2016. The SDF has said Islamic State was using civilians as human shields. (Photo by Rodi Said/Reuters)

A United States Air Force (USAF) F-15 fighter jet travels at low altitude through the “Mach Loop” series of valleys near Dolgellau, north Wales on June 26, 2018. The Mach Loop valleys, situated between Dolgellau and Machynlleth, are regularly used by the military for operational low flying training which can take place as low as 76 metres from the nearest terrain. The USAF regularly use the loop to practice low-altitude flight, which confuses radar systems. (Photo by Oli Scarff/AFP Photo)

Leon Samson, 24-year-old showman, grimaces as an automobile is driven across his chest at Perth, Australia on October 9, 1960. Samson said the towel on his chest is to prevent the wheel from tearing his flesh. (Photo by AP Photo)

Plaster cast moulds of victims of the Mount Vesuvius eruption lie on a display table in a laboratory at Pompeii October 13, 2015. An expert team made up of archaeologists, radiologists, orthodontists and anthropologists began on September 2015 to use CAT scan technology (computerised axial tomography) to peer inside the plaster cast moulds of Pompeii's victims, in a study that has added more detail to previous findings. A 16-layer scan had to be used in order to penetrate the hardened plaster but the results showed up impressive skeletal remains and near perfect teeth. (Photo by Alessandro Bianchi/Reuters)

Girls play with their new dolls during the distribution of free toys for low-income families and a picture on the lap of one of the Three Wise Men at Almudena Cathedral in Madrid, Spain, December 22, 2015. Traditionally, children in Spain receive their presents delivered by the Three Wise Men on the morning of January 6 during the Christian holiday of the Epiphany. (Photo by Susana Vera/Reuters)