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Abstract Endothelial monolayers physiologically adapt to flow and flow‐induced wall shear stress, attaining ordered configurations in which elongation, orientation, and polarization are coherently organized over many cells. Here, with the flow direction unchanged, a peculiar bi‐stable (along the flow direction or perpendicular to it) cell alignment is observed, emerging as a function of the flow intensity alone, while cell polarization is purely instructed by flow directionality. Driven by the experimental findings, the parallelism between endothelia is delineated under a flow field and the transition of dual‐frequency nematic liquid crystals under an external oscillatory electric field. The resulting physical model reproduces the two stable configurations and the energy landscape of the corresponding system transitions. In addition, it reveals the existence of a disordered, metastable state emerging upon system perturbation. This intermediate state, experimentally demonstrated in endothelial monolayers, is shown to expose the cellular system to a weakening of cell‐to‐cell junctions to the detriment of the monolayer integrity. The flow‐adaptation of monolayers composed of healthy and senescent endothelia is successfully predicted by the model with adjustable nematic parameters. These results may help to understand the maladaptive response of in vivo endothelial tissues to disturbed hemodynamics and the progressive functional decay of senescent endothelia.

The classic Leidenfrost phenomenon is familiar, yet its physics is rather complex. Graeber et al. observe the unexpected development of repeated hopping of a droplet trampolining on its own vapor cushion on a hot plate and show under which conditions this self-initiated motion occurs.

It has been shown previously that substrate viscoelasticity affects surface wettability. Here the authors observe a wetting transition during drying of droplets on such substrates and elucidate it with high resolution force field measurements thereby determining its dependence on substrate properties.

We report a highly efficient technique to form novel fluoropolymer blend dispersions containing poly(vinylidene fluoride) (PVDF) and a fluorinated acrylic copolymer using a cosolvent system comprising N-methyl-2-pyrrolidone (NMP), acetone, and water under pH control. We also show that certain surface-functionalized, high-aspect-ratio nanostructured materials, such as organoclay and carbon nanowhiskers (CNWs), can be easily dispersed in these fluoropolymer blends to fabricate durable and functional superhydrophobic composite coatings upon spray casting. Both clay and CNW superhydrophobic coatings also repel lower surface tension liquids, such as water–alcohol mixtures (∼40 mN/m). Repellency is characterized using droplet sessile contact angle and contact angle hysteresis. Both clay and CNW-based composite coatings display self-cleaning properties (low contact angle hysteresis) for both water and water–alcohol mixtures. Additionally, electrical conductivity measurement of CNW composite coatings demonstrates the ability to fabricate multifunctional superhydrophobic composites using these fluoropolymer dispersions. The nanoparticle concentration required in these composite coatings for water and water–alcohol repellency is compared with a previously reported PVDF-based coating system. Wettability is interpreted within the framework of the Wenzel and Cassie–Baxter wetting theories. [ABSTRACT FROM AUTHOR]