A woman reacts as she lays flowers outside the Perm State University following a campus shooting in Perm, about 1,100 kilometers (700 miles) east of Moscow, Russia, Tuesday, September 21, 2021. A student opened fire at the university, leaving a number of people dead and injured, before being shot in a crossfire with police and detained. Beyond saying that he was a student, authorities offered no further information on his identity or a possible motive. (Photo by Dmitri Lovetsky/AP Photo)

Mr. Zhong Hua, of Johns Hopkins University School of Medicine, took this image of the peripheral nerves (those outside of the brain) in an 11.5-day-old mouse embryo, magnified five times. (Photo by Zhong Hua)

Actress/Singer Victoria Justice arrives at the 2012 Teen Choice Awards at Gibson Amphitheatre on July 22, 2012 in Universal City, California. (Photo by Jeffrey Mayer)

Manchester and Salford University students have been celebrate the last day of freshers week in Manchester, England on September 25, 2016. (Photo by Jordan Sinclair/UK News Pictures)

Couples take part in a competition during a mass wedding of 64 doctoral student couples at Harbin Institute of Technology, a university in Harbin, Heilongjiang province, China, June 4, 2017. (Photo by Reuters/Stringer)

An instructor (C) adjusts the posture of students of flight attendant major during a training session at Anhui Foreign Languages University, in Hefei, Anhui province, China, May 25, 2015. (Photo by Reuters/China Daily)

Participants dressed in Heroic Fantasy costumes pose for a picture as they wait backstage during the first edition of the HeroFestival in Marseille, November 9, 2014. The festival is dedicated to American superhero comics, Japanese mangas, Heroic Fantasy characters and video games universes. (Photo by Jean-Paul Pelissier/Reuters)

Kendall Jenner seen at Universal, NBC, Focus Features, E! Entertainment Golden Globes After Party Sponsored by Chrysler on Sunday, January 8, 2017, in Beverly Hills, Calif. (Photo by Eric Charbonneau/Invision for Focus Features/AP Images)