Daniel Pearce

Soft matter physicist trying to understand how things organize themselves.

[UNIGE_en @unige_en]

A team from the UNIGE has shown that the hydra is capable of generating two heads when slight pressure is applied to its body. @RouxLab @Ch_Bioch_UNIGE @sciences_UNIGE
#chemistry #biology #science #research
https://t.co/At3yFyypY3

[@yamini-ravichan.bsky.social @yamini_ravichan]

Here to drop all the eye-candy from our latest preprint on actin defect mediated Hydra morphogenesis @RouxLab @PearceDJG We'd like to thank the @BrigitteGalliot lab for their support and the Keren lab for their valuable feedback on this work! (1/6)
https://t.co/U6VFKqYimE

[Roux Lab @RouxLab]

In our new bioRXiv, @yamini_ravichan shows that soft compression of head-regenerating tissues from Hydra induces bicephalous regeneration. During soft compression, a second actin nematic defects appears on the wound.
https://t.co/dJA6KQ7zCj

[Roux Lab @RouxLab]

Finally, to test whether the topology change or the lack of actin nematic defects was blocking regeneration, @yamini_ravichan generated toroidal tissues with defects, and they regenerated a head and a foot... and even became adult animals.
https://t.co/dJA6KQ71ML

[Roux Lab @RouxLab]

This shows that actin defects are essential for head morphogenesis. Simulations by @PearceDJG and Karsten Kruse show that the defects organise the actin stresses to shape the Hydra tissue into a head and a foot... or two heads and a foot.
https://t.co/dJA6KQ71ML

[Victor Yashunsky @VYashunsky]

The fascinating realm of topological defects in swarming bacteria dynamics in our latest preprint [arXiv.2401.05560].
@VYashunsky, @PearceDJG, G. Ariel, A. Be’er, Topological defects in multi-layered swarming bacteria #ActiveMatter #LivingMatter #cellnematics #SwarmingBacteria

[Victor Yashunsky @VYashunsky]

Nematic defects #cellnematics orient with a tilt toward the boundary and generate edge currents.
@VYashunsky, @PearceDJG, C. Blanch-Mercader, F. Ascione, P. Silberzan, @luca_giomi
Read https://t.co/NKQS3SWD62 @PhysRevX #PRXbio
@institut_curie @LeidenPhysics @unige_en @bidrBGU

[Daniel Pearce @PearceDJG]

Removing phase difference between a pair of topological defects by creating and annihilating more defects. Read about it in our new manuscript in Soft Matter https://t.co/UgSadI1WuB

[Daniel Pearce @PearceDJG]

How to control the motion of defects in liquid crystals by changing the temperature. Preprint out today: https://t.co/ZdoN6Vi773

[Daniel Pearce @PearceDJG]

@AnthonyC1Nash Happy birthday man! The 'Pipe and Slippers' night for your thirtieth feels like yesterday.

[Roux Lab @RouxLab]

Proposed a 100 yrs ago, we show that folding of an epithelium can spontaneously occur by buckling! Congrats to Anastasiya, a wonderful collaboration with the Kruse & Chopard Labs, @sciences_UNIGE, @unige_en, @NCCR_ChemBio
https://t.co/gm1l27NL6L

[Daniel Pearce @PearceDJG]

@shaevitz @dsseara Could you email me some example data? I'll make it work and send you back some code.

[Daniel Pearce @PearceDJG]

New plotting method for nematic fields. I usually show to show the Schlieren texture, but this is much easier to understand and makes it look far more like experiments!

[Daniel Pearce @PearceDJG]

@shaevitz @dsseara Currently it is tailored to work with the field that comes from my simulation. How are your director fields stored? It should be easy to generalize.

[Daniel Pearce @PearceDJG]

@rajphys These are beautiful simulations. Is it an agent based model?

[Daniel Pearce @PearceDJG]

@MarkusDeserno @natxopago Yes, in my simulation the director field exists on a grid, so you can just check each grid point. This representation makes it much easier to identify the charge and orientation of defects by eye though.

[Daniel Pearce @PearceDJG]

Topological defects in active nematic solids can generate curvature depending on their tilt rather than their charge.

[Daniel Pearce @PearceDJG]

@AnthonyC1Nash What happened to you? You've crossed to the dark side!

[Daniel Pearce @PearceDJG]

@AnthonyC1Nash Just use Inkscape man, you're punishing yourself!