Janata was an Aes Sedai who specialized in the study of ter'angreal. After forty years of studying, she was stilled by an unknown ter'angreal. She wasn't heard from again.
Eventually, she resurfaces as Setalle Anan in Ebou Dar and marries Jasfar Anan. In her spare time, she helps the Kin and maintains their secrets.
For more details on Martine Janata, visit Encyclopaedia WoT.