Mario Huettenhofer, chief of the German company 3D Fab, presents his own face as 3d print during the international fairs FabCon 3.D and Rapid.Tech in Erfurt, Germany, Thursday, May 15, 2014. 130 exhibitors from all over the world present the entire world of 3D printing. The trade fairs are accompanied by specialist programs featuring 80 scientists, practitioners and trend analysts from ten countries, who will explain the latest findings, trends and applications for additive processes in industry and for 3D printing in the private sector to newcomers, experts and consumers alike. (Photo by Jens Meyer/AP Photo)

An Army Sikorsky VH-34s Choctaw helicopter once used to transport President Dwight D. Eisenhower sits in a field at the 309th Aerospace Maintenance and Regeneration Group boneyard Thursday, May 14, 2015 at Davis-Monthan Air Force Base in Tucson, Ariz. President Eisenhower became the first chief executive to be transported by helicopter. Presidents Eisenhower and John F. Kennedy were transported in VH-34 helicopters and VH-34's served as “Army One” from 1958 through 1963. (Photo by Matt York/AP Photo)

Reuters photographers Carlos Barria and Bobby Yip photographed protestors and details of life on the barricades, asking demonstrators what their role was in the movement, and what they wanted to happen. Here: Crystal, 15, a part-time boutique sales assistant, poses on Nathan Road in Mongkok shopping district in Hong Kong October 7, 2014. Holding a walkie talkie for fast communication with other supporters, Crystal said, “I am not demanding Chief Executive Leung Chun-ying to quit, but (want) to protect protesters from being threatened badly by opponents and the police”. (Photo by Bobby Yip/Reuters)

This picture taken on January 14, 2021 and released from North Korea's official Korean Central News Agency (KCNA) on January 15 shows Pak Jong Chon, chief of the General Staff of the Korean People's Army, during a military parade celebrating the 8th Congress of the Workers' Party of Korea (WPK) in Pyongyang. (Photo by KCNA via KNS/AFP Photo)

Girls embrace in front of a makeshift memorial for victims by the Covenant School building at the Covenant Presbyterian Church following a shooting, in Nashville, Tennessee, March 28, 2023. A heavily armed former student killed three young children and three staff in what appeared to be a carefully planned attack at a private elementary school in Nashville on Monday, before being shot dead by police Chief of Police John Drake named the suspect as Audrey Hale, 28, who the officer later said identified as transgender. (Photo by Brendan Smialowski/AFP Photo)

Kaia Gerber attends the LOVE Magazine LFW Party, celebrating issue 23 at The Standard, London on February 17, 2020 in London, England. LOVE magazine is welcoming Ben Cobb as Editor-In-Chief Men's, Graham Rounthwaite as Creative Director, and Oliver Volquardsen as Fashion Director. (Photo by David M. Benett/Dave Benett/Getty Images for LOVE Magazine)

Gunfire was brought to the steps of President Truman's Washington home, Blair House, as two assassins tried to kill the chief executive, November 1, 1950. One of the gunmen, Oscar Collazzo of New York, lay wounded at the bottom of Blair House's front steps after the president's police guard had finished their work, at the cost of one guards' life, Dec. 9, 1950. The second gunman was killed. (Photo by Harvey Georges/AP Photo)

This picture released by Turkish Cumhuriyet Daily newspaper shows Dilek Dundar (L), the wife of editor-in-chief of Turkish newspaper Cumhuriyet daily Can Dundar, trying to stop a gunman who is also being held back by a man on May 6, 2016 in Istanbul. Turkish opposition journalist Can Dundar escaped a shooting on May 5 outside a courthouse in Istanbul where he is on trial, adding police detained the assailant. Dundar, who was unharmed, was outside the courthouse during a break as the court prepared to deliver its verdict in his trial for allegedly revealing state secrets in a newspaper story. (Photo by AFP Photo/Cumhuriyet Daily Newspaper)