Grey matter refers to unmyelinated neurons and other cells of the central nervous system. It is present in the brain, brainstem and cerebellum, and present throughout the spinal cord.rey matter refers to unmyelinated neurons and other cells of the central nervous system. It is present in the brain, brainstem and cerebellum, and present throughout the spinal cord.
Kaz Tada (left) was one of those rounded up. Kaz was a Nisei  a person born in America of parents who immigrated from Japan. Nisei is a Japanese word meaning second generation. Isei refers to first generation immigrants, those who came the U.S. from Japan. And Sensei refers to third generation Japanese Americans.
For the martial arts rank of Nidan, see Dan (rank). Nidan (sometimes known as Midan or Idan) was a Welsh priest and, according to some sources, a bishop, in the 6th and 7th centuries. He is now commemorated as a saint.