謝孝

谢 = 射 + 讠 : Marie Curie (xi) just came back from her trip to outer space and is standing in front of the launch pad (射) in the elevator's bathroom (e4). She thanks (谢) her sponsors and points towards the sponsors' advertising column (讠), saying that it would have been impossible to go to outer space without their funding.

孝 = ⺹ + 子 : Mnemonic symbol: a mourning veil.

Xi Shi (xi) was breeding an egg (子) in the aorta's bathroom (ao4), and she even put a crown (⺹) on it (the crown is on top of the egg: 孝), so much she loved her little prince. Unfortunately the egg died, and thus Marie Curie put on her mourning veil (孝).