Scaling laws of plume-induced granular cratering.

Extraterrestrial landing often requires firing a high-speed plume towards a planetary surface, and the resulting gas-granular interactions pose potential hazards to the lander. To investigate these jet-induced cratering dynamics, an experiment campaign covering a range of gas and granular properties relevant to the lunar and Martian environments was conducted in a large-scale vacuum chamber. Despite the variations in jet Mach number, mass flow rate, and composition of the granular phase investigated in this work, the observed time evolution of crater depth displays a consistent transition from an early-stage linear to a late-stage sublinear growth.

Transplacental passage of antimicrobial paraben preservatives.

Parabens are widely used preservatives suspected of being endocrine disruptors, with implications for human growth and development. The most common paraben found in consumer products is methylparaben. To date, no study has examined whether these substances cross the human placenta.