Al-Ghoul's Research Group (AUB)

https://www.nature.com/articles/s41467-023-40338-2

The reaction-diffusion basis of animated patterns in eukaryotic flagella - Nature Communications In 1952, Turing unlocked the reaction-diffusion basis of natural patterns, such as zebra stripes. The authors propose a reaction-diffusion model that recreates characteristics of the flagellar waveform for bull s***m and Chlamydomonas flagella.

Materials like oobleck — a suspension of cornstarch particles in water — are tough to classify. In some circumstances, they behave like a fluid, but in others, they act like a solid. Here researchers sandwiched a thin layer of oobleck between glass plates and injected air into the mixture. For a fluid, this setup creates a classic Saffman-Taylor instability where rounded fingers of air push their way into the more viscous fluid. And, indeed, for low air pressures and low concentrations of cornstarch, the oobleck forms these viscous fingers. You can see examples in the top row’s first and third image, the second row’s middle image, and the bottom row’s third image.

Injecting air at high pressures and high cornstarch concentrations fractures the oobleck like a solid (middle row, first and third images). At intermediate pressures and concentrations, the oobleck forms a pattern called dendritic fracturing, where new branches can grow perpendicularly to their parent branch. Examples of this pattern are in the top row’s second image and the bottom row’s first and second images. (Image and research credit: D. Ozturk et al.)
https://www.nature.com/articles/s42005-020-0382-7

Banded agate

Uncovering life’s operating code By examining artificial systems with life-like qualities, Meiji University chemist seeks to better understand biological life.

Turtle shell pattern variations

Polished large purple labradorite from Madagascar

Credit: Natures_goodz

Ice streaks the sand dunes of the Sahara Desert in northwestern Algeria.
(Image: © Karim Bouchetata)