Publication

In a recent work, researchers show that particles entrained in a flow close to a deformable wall undergo a force that moves them slightly away from it, an important result for the general understanding of transport phenomena in biology.

At the heart of the Arabidopsis thaliana flower, the pistil, formed of hundreds of papillae and an ovary housing the ovules, is surrounded by stamens that release pollen grains carrying male gametes. In an article published in PLOS Computational Biology, scientists combine theory and experiments to reveal how male gametes are guided toward the ovules from the very beginning of their journey on the surface of the female reproductive organ.

Cyanobacteria have an internal biological clock that rhythms their activities on a 24-hour cycle. Thanks to this finely regulated mechanism, these micro-organisms are able to anticipate day/night cycles. A study recently published in Scientific Reports looked at how this clock reacts when the temperature drops below 25°C, an important threshold for their physiology.

Using laser nucleation of microbubbles, physicists have shown that stomata, the miniature 'gates' that regulate light-dependent evaporation in vascular plants, remain inactive in non-vascular plants such as mosses.

Macrophages are immune system cells that ingest and degrade microorganisms and cellular debris in a process called phagocytosis. In a study published in iScience, scientists show that the mechanical properties of the tissues surrounding macrophages influence phagocytosis, which in turn affects the way macrophages interact with their environment.

To better understand the formation, composition and evolution of the atmospheres of terrestrial planets, scientists at LIPhy have developed spectrometers using optical cavity spectroscopy (CRDS). Their high sensitivity enables them to accurately record the absorption spectra of various molecules of atmospheric and planetary interest, such as dihydrogen, water or methane, mixed with carbon dioxide.

Bubbles are ubiquitous in many research applications, from ultrasound imaging to understanding volcanic eruptions. They are also excellent acoustic resonators, being very small in size compared to the wavelength of the sound they emit. These resonant sound waves contain information about the mechanical properties of materials in the immediate vicinity of the bubble. In a recent publication in Nature Communications, a collaboration between LIPhy's Optima and Move teams proposes to exploit this phenomenon to image a sample by moving a bubble in its vicinity.

By combining a numerical modeling approach with experiments in both structural and cellular biology, the APERTuRe project has led to a better understanding of the dynamics of a protein network in the cytoplasm of our cells. These results could prove useful in the development of new drugs.

In an article published in Nature Microbiology, scientists have deciphered the rapid gliding strategy of the parasitic microbe Toxoplasma gondii within the host organism's tissues. They show how the parasite is able to hold on tightly enough without sticking to its substrate to glide efficiently. By explaining how a minimal adhesion system is able to generate rapid movement within complex microenvironments, they open up perspectives for other models of cellular interactions.

A Franco-American collaboration has demonstrated that in the microcirculatory network, some red blood cells can take unexpected routes to get from one point to another. This experimental observation should lead to more precise modeling of the mechanisms of oxygenation and elimination of the residues of cellular activity within the blood network.