In the mirror universe, Kal Dano was a Shirna scientist from the 27th century who invented a device known as the Tox Uthat, a quantum phase inhibitor capable of stopping all nuclear fusion within a star.
Dano was pursued by two Vorgon criminals, Ajur and Boratus, who wanted the device. Dano travelled into the past in order to hide it. He booby trapped the Uthat to self-destruct if anyone attempted to use it. It was eventually discovered by the Terran archaeologist for hire Jean-Luc Picard in 2377. However, it was almost immediately destroyed by the Memory Omega operative K'Ehleyr. (ST - Mirror Universe novel: Rise Like Lions)