The doors have electric eyes: If you're carrying large specimens or carts full of plants, the electric eye beam is broken and the door opens up.

His strength and stamina were doubted; he was a youth of not more than 19 years of age, nearly six feet high, 12 stone in weight, but thought to have more gristle than bone: his victualling office had also been some time out of commission; […]

the eve of a scientific discovery

2020, Mumtaz Yaseen Balkhi, Basics of Chimeric Antigen Receptor (CAR) Immunotherapy, Elsevier (Academic Press).