Masato is professor emeritus at Hitotsubashi University in Tokyo, it seems. So he probably wouldn't go in to work every day anyway, and communications there are difficult, even though most people are safe.

There are quite a few people with the same name. This Wikipedia page (on a Japanese version of Auld Lang Syne) makes it clear which is the right one:

http://en.wikipedia.org/wiki/Aogeba_t%C5%8Dtoshi