zwickergroup.bsky.social
Theoretical biophysics group at MPI-DS, Göttingen. We study the spatiotemporal organization of soft matter in cells, tissues, and synthetic systems; see www.zwickergroup.org
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Totally agree - the worst are „outlines“ that simply state that the speaker will start with an introduction, then talk about the main results, and finishes with a summary. Similarly useless are slides that simply state „Thank you“ at the end of a talk - leave the summary slide instead!
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It’s a great conference - enjoy the discussions!
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We were so annoyed with `imshow` for creating density plots that we wrote a whole `densityplot` module to produce density plots conveniently (including log-scaled axes!). Our package is available on pypi (as part of the `utilitiez` package) and on GitHub: github.com/zwicker-grou...
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We might say the same thing, though :) A good introduction in my mind includes goals and gives the audience a map to follow. Details should then be filled in later. Maybe it’s just semantics that are difficult to discuss online….
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Are you saying that the presenter should not tell the audience about the rough plan for the presentation? I might misunderstand your point, but I strongly believe the presenter should tell the audience about their goal and the way toward it. Without such a map, the audience might get lost…
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It was indeed a great conference with surprisingly diverse topics. The interactive discussion rounds were particularly stimulating! Congratulations to the organizers for making such a stimulating conference possible 🎉
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It was a great conference with such diverse topics. The interactive discussion rounds were particularly stimulating! Congratulations to the organizers for making such a stimulating conference possible 🎉
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We looked at a related effect of growth/dilution on circadian rhythms in this theoretical paper: dx.doi.org/10.1073/pnas...
The O'Shea lab later confirmed a critical influence of growth rates in experiments: dx.doi.org/10.1126/scie...
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We already used this package to identify a vast nucleation-and-growth regime in generic multicomponent mixtures. You can read a summary of that story at @natchemeng.bsky.social (To mix or not to mix? doi.org/10.1038/s442...) and the corresponding #preprint is available at arxiv.org/abs/2405.01138.
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I agree! The best I can probably do (with my limited illustrator skills) is the figure below. I think this is already better than what we had before, so thanks for the suggestion!
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That’s a very good point, which we briefly mention in the review. I’ll try to adjust the schematic to emphasize this better!
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We just updated our review (arxiv.org/abs/2501.13639) to add additional references, fix some mistakes, and particularly expand the derivation of thermodynamically consistent chemical reactions. We're still interested in your feedback!
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Congratulations! That’s amazing! I also like the theme of failure - just this week we discussed in our group how often we’re confused and that that’s a good sign in science!
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In essence, these effects follow from the delicate balance of enthalpy and entropy, which affect the equilibrium state and the stability of the homogeneous state differently. Overall, these multicomponent mixtures are another example for emergent behavior, which describes complex phenomena!
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More generally, we derive scaling laws for the number of coexisting phases. This allows us to predict that typical multicomponent mixtures can have many different droplets (large N_p) even when the homogeneous state is stable (small N_u), showing the multistability more generally.
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The little text summarizes the main result of a longer article that we recently updated on arxiv: arxiv.org/abs/2405.01138
For instance, we show that a concrete system possesses many stable states with various droplets, indicating that this system is multistable.
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We also use the package for teaching since it only requires minimal knowledge of Python.
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Good luck with the extension!
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We started thinking about this review about 3.5 years ago (thanks Estefania and Jan!) and updated the draft continuously. Yet, there surely will be mistakes and missed references, so please reach out if you have ideas for improvements!
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Taken together, these physical processes allow cells to control droplets, and vice versa.
We hope that our review provides useful links between the biology and soft matter literature. We also hope that it is useful for people who want to study condensates theoretically!
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Third, cells are alive and use fuel to drive processes out of equilibrium. In particular, they can modify the physical interactions of molecules against the thermodynamic tendency. The resulting active matter can exhibit controlled nucleation, shape deformations, and even division.
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Second, the cellular environment contains many solid-like structures, like the cytoskeleton, and softer structures, like membranes. Condensates interact with those structures by wetting, which affects their shape, size, and location.
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First, condensates comprise many different biomolecules, which are diverse and individually complex. This implies that cellular droplets posses complex internal behavior, e.g., in terms of their material properties.
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Interestingly, the segregation strength affects droplet size only weakly, which we confirmed with simulations. Our work shows how charge can control droplet size, e.g., to regulate #condensates inside biological cells. It also shows that simple screening (e.g., Debye-Hückel theory) can be misleading
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We also analyzed the corresponding field theory and found equilibrium states with periodic patterns, which correspond to arrested droplet sizes. The pattern period decreases with larger charge asymmetry due to a trade-off between interfacial and electrostatic effects (see schematic).
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The main point is that the salt ions, that usually neutralize charges locally and thus mediate screening, can be affected by phase separation. In our example, salt ions get expelled from droplets, so droplets acquire a net charge, and cannot grow indefinitely; see attached MD simulations.