Commuters walk up the redesigned subway stairs at the Tanjong Pagar subway station on August 23, 2011 in Singapore. The subway stairs have been repainted in bright colours and slogans encouraging people to take the stairs, by way of promoting fitness in the city. (Photo by Chris McGrath/Getty Images)

Engineer Thomas Dwyer stands with the new Bionic Exoskeleton next to Amanda Boxtel during its launch at the Excel centre on October 21, 2011 in London, England. The bionic device developed by Ekso Bionics is a wearable, battery-powered, robotic exoskeleton, designed to aid wheelchair users and those who have suffered from spinal chord injuries to stand and walk. (Photo by Dan Kitwood/Getty Images)

Actress Rosario Dawson (“Men in Black II”, “25th Hour”, “Sin City”, “Death Proof”, “Eagle Eye”, “Alexander”, “Percy Jackson and the Olympians”) walks the runway at the Fashion For Relief at Forville market during the 64th Annual Cannes Film Festival on May 16, 2011 in Cannes, France. (Photo by Ian Gavan/Getty Images)

This photo released Saturday March 22, 2014 by Stichting Ambulance Wens or Ambulance Wish Foundation shows a giraffe at Blijdorp Zoo in Rotterdam giving a lick to terminally ill Mario Eijs on Wednesday March 19, 2014. The Stichting Ambulancewens “Ambulance Wish Foundation” offers transport for terminally ill patients who cannot walk to help fulfill a last wish, in Eijs' case to be taken to the Blijdorp Zoo in Rotterdam where he worked doing odd jobs for 25 years. Eijs, who has a mental handicap, is dying of a brain tumor and has difficulty walking or speaking. (Photo by AP Photo/Stichting Ambulance Wens)

A woman walks with her baby past a PM militarized police soldier in position and aiming his rifle in Rocinha favela in Rio de Janeiro, Brazil on September 23, 2017. Although shooting was reported in the early hours of Saturday in Rocinha – for the seventh day running – officials said that Friday's deployment of 950 soldiers to reinforce police had brought the crisis under control. (Photo by Carl De Souza/AFP Photo)

Arlo Dela Cruz and Maica Nicerio-Dela Cruz on their wedding day with the Mayon volcano erupting in the background, in Daraga, Albay, Philippines on January 25, 2018. They were married earlier in the afternoon at Our Lady of the Gate Parish. After their wedding they walked out to Red Labuyo restaurant and the volcano started its eruption. The Mayon volcano continued to erupt Thursday. The airport in Legazpi is closed until at least 31 January 2018. (Photo by ZUMA Press/Alamy Stock Photo)

A deer walks across a pedestrian crossing in Nara, Japan, Thursday, March 19, 2020. More than 1,000 deer roam free in the ancient capital city of Japan. Despite the town's tourism decline, these wild animals are doing just fine without treats from tourists, according to a deer protection group. (Photo by Jae C. Hong/AP Photo)

A group of people walk on the sea wall as a man kayaks through the flooded parking lot in downtown Annapolis, Maryland, on October 29, 2021. The US National Weather Service implemented a flood watch for the cities of Baltimore and Annapolis as well as Anne Arundel, Baltimore and Howard counties. Washington, DC, and parts of Virginia faced the same alert. (Photo by Jim Watson/AFP Photo)