The 23 London athletes are in addition to the 31 who tested positive in retesting from the Beijing Olympics.
Mars is emerging from an ice age, a finding that could shed light on the past and future climates of both Mars and Earth, researchers said.
Eight automakers said on Friday they are recalling more than 12 million vehicles in new recalls related to defective Takata air bags.
In August 1945, Hiroshima became the first city in the world to be struck by an atomic bomb.
The Airbus A320 crashed on May 19 with 66 people on board.