Ituka, tabi ipofo okun-inu, unsele nigbati atomu kan to ni iru nukleu kan, to unje radionuklidi obi, yirapada di atomu to ni nukleu kan ni ipoaye to yato, tabi to di nukleu oto to ni iye proton ati neutron oto.. 
Nathani "Natce Turner (October 2, 1800 – November 11, 1831) jẹ́ ẹrú ará Amẹ́ríkà tó léwájú ìkọ́ya àwọn ẹrú ní Virginia ní August 21, 1831.ìtọ́kasí.. 