A member of the United States Naval Academy freshman class wears body armor, helmet and carries a rifle through a mud-filled ditch as part of the “Wet and Sandy” challenge during the rigorous Sea Trials May 17, 2011 in Annapolis, MD. Under strict safety supervision, about 900 freshmen, or “Plebes”, faced 14 hours of 32 rigorous physical and mental challenges during the trials, a daylong, action-oriented event modeled after the Marine Corps 54-hour Crucible and the Navy's Battle Stations. (Photo by Chip Somodevilla/Getty Images)

Members of China Disabled Peoples Performing Art Troupe perform “Thousand-arm Goddess of Mercy” during a show on March 12, 2005 in Guangzhou of Guangdong Province, China. China Disabled Peoples Performing Art Troupe was established in 1987. It is an amateur mass art troupe composed of visually impaired, audibly impaired and physically and mentally challenged people. In the past nearly two decades, the troupe has visited more than 30 countries and regions, winning the hearts of audiences all over the world by their solid background of Chinese Culture and their colourful national charm. (Photo by China Photos/Getty Images)

Passengers pose for a selfie as they wait for the Night Tube train service at Oxford Circus on the London underground system in London, Britain August 20, 2016. The London Underground is starting its first-ever overnight service, a move city leaders hope will make the British capital a truly 24-hour city and bolster the local economy. (Photo by Paul Hackett/Reuters)

Nursing and care personnel lay on the floor in the ICU unit, during a demonstration on International Nursing and Care day, at the Mont Legia Hospital in Liege, Belgium, Wednesday, May 12, 2021. Hospital personnel around Belgium took part in various actions around the country on Wednesday to highlight the work they do and demand better recognition. (Photo by Valentin Bianchi/AP Photo)

A veterinarian kisses an 8-month-old cat, wearing a prosthetic two-wheel device, at a veterinary hospital in Chongqing municipality, March 16, 2015. The cat's rear legs lost the abilty to walk after falling from the ninth to fifth floor of a building last November, its since undergone four major surgeries which included removing parts of its organs, local media reported. (Photo by Reuters/China Daily)

An Afghan man is carried out of a hospital after receiving treatment following a suicide truck bomb attack in Kabul, Afghanistan August 7, 2015. The bombings were the first in Kabul since Mullah Akhtar Mansour took charge of the Taliban last week, and followed a rare truck bomb attack in an eastern province on Thursday. (Photo by Omar Sobhani/Reuters)

A Palestinian social activist working for the International South South Cooperation (Cooperazione Internazionale Sud Sud, or CISS) entertain children who are patients inside a hospital in Gaza City August 31, 2015. Activists working for the Italian non-profit NGO use entertainment and humour to help bring treatment to children suffering from psychological trauma in the Gaza Strip. (Photo by Mohammed Salem/Reuters)