With no explanation, label text_A→text_B with either "not_related" or "related".
text_A: Rockefeller University is in a state.
text_B: The regeneration of the lens of the eye has been studied , mostly in amphibians and rabbits , from the 18th century .. regeneration. regeneration in humans. lens. lens ( anatomy ). In the 21st century , an experimental medical trial has been performed in humans as this is a promising technique for treating cataracts , especially in children .
not_related.