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Several mathematical models have been developed to describe pattern formation in biological tissues: the Turing, Cahn-Hilliard, Swift-Hohenberg, and chemotaxis models are among the most famous ones. Yu et al. characterize a different class of such models, one in which not chemical species but the cells themselves move and aggregate, collectively termed directed cell migration, showing under which conditions this family of models has the potential to explain rapid biological-patterning processes using theory and accessible simulations.

Ultrafast thermodynamics extends non-equilibrium thermodynamics to material excitations on sub-nanosecond timescales. In this perspective, Tietjen et al. provide an outline of this research field together with a discussion of future directions.

Conventional damping elastomers soften at elevated temperatures because the molecular motions responsible for energy dissipation simultaneously undermine mechanical stiffness. Leveraging the dynamic coupling behavior between the infused polymer fluids and interphase on the nanoparticle surface switched by the Flory-Huggins parameter, Zha et al. report a complex fluid gel that combines high energy dissipation over a wide temperature/frequency range and high-temperature mechanical reinforcement. These findings provide a new strategy for mechanical regulation in high-temperature environments.

Topological modes associated with bulk-edge correspondence usually appear as boundary or interface states with exponentially decaying spatial profiles. Liu et al. use feedback-induced nonlinearity in an active mechanical lattice to broaden, relocate, and write such edge modes into prescribed sine, square, and triangle envelopes. Quadratic pseudospectrum analysis quantitatively corroborates edge responses and real-space profiles. Together, these results establish an experimental blueprint for programmable edge localization and shape coding in reconfigurable wave devices.

Conventional theory suggests that ice adhesion reduction is primarily due to strain resulting from the coefficients of thermal expansion mismatch between ice and substrate. Sarma et al. propose a model that demonstrates thermo-mechanical coupling, incorporating the thermal conductivity of the substrate, which is crucial for decreasing ice adhesion, achieving ultralow adhesion and promoting easy de-icing.

Colloidal particles and their self-assembled clusters can serve as building blocks for functional materials. Yang et al. elucidate how competing forces govern evaporation-driven colloidal self-assembly using simulations showing that evaporation rate and interparticle friction steer colloidal assembly pathways and cluster formation. This work provides mechanistic guidance for the design of colloidal clusters with target structures.

Single-particle heat engines operate in a fluctuation-dominated regime. Roy et al. realize a macroscopic single-particle stochastic Stirling engine using a vibrofluidized granule with engineered Brownian-like dynamics. Despite being intrinsically athermal, this engine reproduces universal finite-time thermodynamics bounds, including the Curzon-Ahlborn efficiency. Surprisingly, dissipation during compression rivals that during expansion due to confinement-dependent damping. This tabletop experimental platform bridges granular matter and stochastic thermodynamics, offering a versatile route to probe non-equilibrium energy conversion and system-bath coupling in small-scale engines.

Mixtures of two different polymers in a common solvent can phase separate in opposite ways, depending on their interactions. Tuinier and González García show that repulsion drives segregative liquid-liquid phase separation, in which each polymer enriches a separate phase, whereas sufficient attraction produces associative liquid-liquid phase separation, in which both polymers concentrate into a dense coacervate. Analytical expressions for critical points and binodals reveal that the two modes are thermodynamically distinct and that their interfaces differ markedly in tension and sharpness.

Passive polymers in active turbulence show a striking size-dependent response: short chains collapse, whereas long chains stretch. Valei et al. show that this transition is controlled by the competition between polymer size and active-flow structure, revealing a defect-mediated route to polymer conformational control.

Cs2SnI6 is a promising lead-free perovskite for solar cells, yet its experimental efficiency lags behind theoretical limits. Using ultrafast terahertz spectroscopy, Lan et al. reveal that photocarriers do not behave as well-defined quasiparticles but evolve through transient excitonic and polaronic states. This many-body evolution suppresses transport while enabling symmetry-sensitive nonlinear photocurrents via Rashba-type effects, linking limitations and functionality.