This left nuclear interactions of very energetic cosmic rays with atmospheric nuclei as the only possible source.
Ependymomas are composed of cells with regular, round to oval nuclei.
The process continues as a chain reaction with other nuclei.
The dineutron hypothesis had been used in nuclear reactions with exotic nuclei for a long time.
Typical cases are small to intermediate sized cells with irregular nuclei.
It was apparently another 2 billion years before more complex cells with nuclei evolved.
Most of them activate a nucleus before reaching the ground; a few react with nuclei in the air.
This could be numerous chemical elements with various radioactive nuclei.
Muscles consist of muscle fibers, long cells with multiple nuclei.
However, most other vertebrates have red cells with nuclei.
