In a hybrid vehicle, an ECU collects data of an amount of acquisition electrical power acquired when regeneratively charging a battery and an amount of requirement electrical power required for operating a motor, for every road section in association with a travel of the vehicle, and records the collected data in a storage device. The present inventors have found that proliferation was promoted and apoptosis reduced when cells were grown in lowered oxygen as compared to environmental oxygen conditions traditionally employed in cell culture techniques. The second recording layer is disc-shaped, arranged on the first recording layer and has a second recording track path formed in an opposite direction to the first recording track path for recording recording information.