Complex sentence: Teresina is the second capital with the best quality of life of North-Northeast second FIRJAN, and according to the IPEA is the third safest capital of Brazil (second only to Natal/RN, and Palmas/TO).
Split into simpler sentences: Teresina is the second capital with the best quality of life in the North-Northeast acording to FIRJAN. According to IPEA it is the third safest capital of Brazil (second only to Natal/RN, and Palmas/TO).