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Many-body interactions in systems of active matter can cause particles to move collectively and self-organize into dynamic structures with long-range order. In cells, the self-assembly of cytoskeletal filaments is critical for cellular motility, structure, intracellular transport, and division. Semiflexible cytoskeletal filaments driven by polymerization or motor-protein interactions on a two-dimensional substrate, such as the cell cortex, can induce filament bending and curvature leading to interesting collective behavior. For example, the bacterial cell-division filament FtsZ is known to have intrinsic curvature that causes it to self-organize into rings and vortices, and recent experiments reconstituting the collective motion of microtubules driven by motor proteins on a surface have observed chiral symmetry breaking of the collective behavior due to motor-induced curvature of the filaments. Previous work on the self-organization of driven filament systems have not studied the effects of curvature and filament structure on collective behavior. In this work, we present Brownian dynamics simulation results of driven semiflexible filaments with intrinsic curvature and investigate how the interplay between filament rigidity and radius of curvature can tune the self-organization behavior in homochiral systems and heterochiral mixtures. We find a curvature-induced reorganization from polar flocks to self-sorted chiral clusters, which is modified by filament flexibility. This transition changes filament transport from ballistic to diffusive at long timescales.
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http://dx.doi.org/10.1039/d0sm01163k | DOI Listing |
Proc Natl Acad Sci U S A
September 2025
Department of Artificial Intelligence, Donders Center for Cognition, Radboud University, Nijmegen, GD 6525, Netherlands.
We present a geometric design rule for size-controlled clustering of self-propelled particles. We show that active particles that tend to rotate under an external force have an intrinsic, signed parameter with units of curvature which we call curvity, that can be derived from first principles. Experiments with robots and numerical simulations show that properties of individual robots (radius and curvity) control pair cohesion in a binary system, and the stability of flocking and self-limiting clustering in a swarm, with applications in metamaterials and in embodied decentralized control.
View Article and Find Full Text PDFBioorg Med Chem Lett
September 2025
Department of Chemistry, Taras Shevchenko National University of Kyiv, Kyiv 01601, Ukraine. Electronic address:
Phospholipid-derived nanocarriers represent a versatile and chemically customizable class of drug delivery systems that self-assemble into bilayered vesicles due to their intrinsic amphiphilicity. These systems can encapsulate both hydrophilic and hydrophobic drugs through non-covalent interactions and manipulation of lipid phase behavior. This review examines the molecular and supramolecular principles underlying the formation, stability, and functional performance of key phospholipid-based nanocarriers-including liposomes, transferosomes, ethosomes, invasomes, phytosomes, pharmacosomes, and virosomes.
View Article and Find Full Text PDFNat Commun
September 2025
Department of Artificial Intelligence, Donders Center for Cognition, Radboud University, Nijmegen, The Netherlands.
Cooperative transport is a striking phenomenon where multiple agents join forces to transit a payload too heavy for the individual. While social animals such as ants are routinely observed to coordinate transport at scale, reproducing the effect in artificial swarms remains challenging, as it requires synchronization in a noisy many-body system. Here we show that cooperative transport spontaneously emerges in swarms of stochastic self-propelled robots.
View Article and Find Full Text PDFJ Am Chem Soc
August 2025
Department of Chemistry, Stanford University, Stanford, California 94305, United States.
Micron-sized water droplets promote redox reactions that are absent in bulk water, yet the kinetics of these interfacial processes remain poorly understood. Here we use real-time fluorescence imaging to monitor spontaneous hydrogen peroxide (HO) generation in individual microdroplets. Both the apparent production rate and equilibrium concentration of HO increase with decreasing droplet size, even after normalizing for surface area, revealing an intrinsic curvature-dependent enhancement.
View Article and Find Full Text PDFPhys Rev Lett
August 2025
University of California, Department of Physics, Berkeley, California 94720, USA.
The quantum metric and Berry curvature capture essential properties of nontrivial Bloch states and underpin many fascinating phenomena. However, it becomes increasingly evident that a more comprehensive understanding of quantum state geometry is necessary to explain properties involving Bloch states of multiple bands, such as optical transitions. To this end, we employ quantum state projectors to develop an explicitly gauge-invariant formalism and demonstrate its power with applications to nonlinear optics and the theory of electronic polarization.
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