Outstanding Referee: Andrea Puglisi

Congratulations to Andrea Puglisi for being chosen for the APS Outstanding Referees 2020 award.
Past award winners have been:
2019 Jose Lorenzana
2018 Stefano Lepri
2016 Lara Benfatto
2011 Massimo Cencini
2008 Alessandro TorciniRead the rest

Alignment of Nonspherical Active Particles in Chaotic Flows – Physical Review Letters

Massimo Cencini has published Alignment of Nonspherical Active Particles in Chaotic Flows in Physical Review Letters.

Active particles, such as motile microorganisms or artificial microswimmers, swim in a surrounding flow, either externally imposed or self-generated. Besides transporting the active particles, the flow velocity change their swimming direction by exerting a shape-dependent torque through the velocity gradients. The complex interplay of flow advection, particle orientation and self-propulsion is fundamental to understand key processes at the crossroad between aquatic ecology, active matter modeling, and nano/micro- technology with application to drug delivery.… Read the rest

NAR: Energetic funnel facilitates facilitated diffusion

Massimo Cencini has published Energetic funnel facilitates facilitated diffusion in Nucleic Acid Research.

Gene transcription is regulated by proteins – Transcription Factors (TFs) – that by binding to short target sequences are able to promote or impede the binding of RNA-Polymerase (RNAP) and, consequently, activate or repress tran-
scription. Fast and accurate control of gene expression is crucial for many biological functions, and relies on the ability of TFs to rapidly find their transcription factor binding site (TFBS) among a multitude of competing DNA sequences,
and to establish with it a stable complex.… Read the rest

Synchronization of extended systems

Synchronization is a long known phenomenon dating back to Huygens experiments who observed that suspending two pendula “…in the same wooden beam, the motions of each pendulum in opposite swings were so much in agreement that they never receded the least bit from each other and the sound of each was always heard simultaneously“. In spite of the early discovery, the phenomenon was fully understood much later with the experiments and theoretical analysis of E.… Read the rest

Transport in binary mixtures

When a binary fluid mixture at the critical concentration is cooled from a high temperature to a sufficiently low temperature (below a critical one), the original homogeneous phase becomes unstable and spontaneously evolves into two phases separated by an interface. As time advances, an out-of-equilibrium process of phase ordering takes place through the formation of domains of a single phase that grows algebraically in time as L(t)~t1/3.… Read the rest

Lagrangian Turbulence

Recently, part of the research activity on turbulence has focused on temporal properties of turbulent statistics which are much less known than the equivalent spatial properties, and are expected to bring information on some of the mechanisms responsible for intermittency in turbulence, for example lagrangian motion is strongly affected by the presence of vortical motion around vortex filaments (see Figure 1).… Read the rest

Scalar Turbulence

The ability of efficiently mixing transported substances is one of the most distinctive properties of turbulence. For instance, it is turbulence (induced by the spoon) that allows cream to rapidly invade a cup of coffee, indeed if only molecular diffusion would be at play in the coffee at rest the same process would require many hours! Given the statistical complexity of a turbulent velocity field, it is natural to wonder about the resulting complexity in the statistical features of the transported concentration field of a substance (e.g.… Read the rest

Inertial Particles in Turbulent Flows

We already mentioned that enhanced mixing is probably one of the most distinguishing feature of turbulence. When a turbulent flow is seeded with particulate matter having a finite size and/or density different from that of the carrier fluid, new features appear. The figure on the left show the instantaneous position particles which are heavier (e.g. water drops in air) resp. lighter (e.g.… Read the rest