One hundred and ten years ago, Marie Sklodowska Curie was formally rejected for membership by the French Academy of Sciences.

Protests erupted in cities across Russia on Saturday to demand the release of opposition leader Alexei Navalny, the Kremlin's most prominent foe. Police arrested more than 1,600 people, some of whom took to the streets in temperatures as frigid as minus-50 Celsius (minus-58 Fahrenheit).

A major British doctors' group says the U.K. government should "urgently review" its decision to give people a second dose of the Pfizer-BioNTech coronavirus vaccine up to 12 weeks after the first, rather than the shorter gap recommended by the manufacturer and the World Health Organization.