Seminars

Contact : Vincent Démery
vincent.demery (arobase) espci.fr
Tel : 33(0)140794552

Map

The Gulliver seminars take place every Monday at 11:30 am in the F304 room, and last one hour including questions. The seminars are in English, and the scientific topics are mainly those studied in the laboratory.



Joseph Paulsen (Joliot Chair & Syracuse University, USA)

Lundi 11 avril 2016 11:30-12:30 - Bibliothèque PCT - F3.04

Noise Stabilization of Multiple Memories in Sheared Non-Brownian Suspensions

A system with multiple transient memories can remember a set of inputs, but will forget most of them, even as they are continually applied. If noise is added, the system can store all memories for much longer. This behavior is a remarkable and counterintuitive example of how information can be stored in disordered systems that are out of equilibrium. Originally observed in traveling charge-density waves, these memories were recently predicted to occur in cyclically sheared non-Brownian suspensions. We perform experiments on such suspensions, and we find behavior that is consistent with multiple transient memories that are stabilized by noise.​

Top







Seminar archive  (173)

  • 2017

    • Pascal Damman (Université de Mons, Belgique)
      Lundi 24 avril 11:30-12:30 - Bibliothèque PCT - F3.04
      Preys capture by chameleons through viscous adhesion
      Several predators use an adhesive tongue to catch preys. Among theseones, chameleons are able to capture large preys by projecting the tongue at high acceleration. Once in contact with a prey, the tongue retracts with a comparable acceleration to bring it to the mouth. A strong adhesion between the tongue tip and (...)
    • Guillaume Grégoire (Institut de Calcul Intensif, ECN and MSC, Université Paris Diderot)
      Lundi 10 avril 11:30-12:30 - Bibliothèque PCT - F3.04
      Flowing suspension of fibres in an effective solvent
      Composite materials are made of fibres which are embed in a matrix. Their micro-structures, their organisations lead to peculiar mechanical properties. But the manufacturing processes are made of multiphysics steps during which the material is heated up and sheared, for instance. It is well known that such (...)
    • Jacqueline Bloch (Laboratoire Photonique et Nanostructures, Marcoussis)
      Lundi 3 avril 11:30-12:30 - Bibliothèque PCT - F3.04
      Quantum fluids of light in semiconductor microcavities
      Semiconductor microcavities appear today as a new platform for the study of quantum fluids of light. They enable confining both light and electronic excitations (excitons) in very small volumes. The resulting strong light-matter coupling gives rise to hybrid light-matter quasi-particles named cavity polaritons. (...)
    • Randall Kamien (University of Pennsylvania, USA)
      Lundi 27 mars 11:30-12:30 - Bibliothèque PCT - F3.04
      Scissors Beats Paper
      I will describe work on the puzzles of periodic order (like crystals) on intrinsically curved surfaces (bumps). I will then demonstrate a partial method to avoid pitfalls by using the method of kirigami, `cut paper', to build curved materials that maintain a certain crystalline (...)
    • Ralf Everaers (ENS Lyon)
      Lundi 20 mars 11:30-12:30 - Bibliothèque PCT - F3.04
      Pincus relations for randomly branched polymers
      Randomly branched polymer chains (or trees) are a classical subject of polymer physics with connections to the theory of magnetic systems, percolation and critical phenomena. More recently, the model has been reconsidered for RNA, supercoiled DNA and the crumpling of topologically constrained polymers. While (...)
    • David Lacoste (Gulliver, ESPCI)
      Lundi 20 mars 11:30-12:30 - Bibliothèque PCT - F3.04
      Information theoretic analysis of stochasticity in metabolism
      Fluctuations in gene expression and growth rate of single cells can have important consequences for cellular function and fitness. In ref [1], fluctuations in the instantaneous growth rate of single cells of Escherichia coli and in the expression of metabolic enzymes have been measured using time-lapse microscopy. (...)
    • James Forrest (University of Waterloo, Canada, Chaire Joliot)
      Lundi 13 mars 11:30-12:30 - Bibliothèque PCT - F3.04
      Some polymer physics at small N
      The polymerisation index, N, is one of the most important parameter in determining polymer behavior. A large majority of work in polymer science focuses on large N, where the polymer molecules behave almost like random chains. I will present some of our recent experimental findings using near oligomeric (...)
    • Florian Hollfelder (University of Cambridge, UK)
      Lundi 27 février 11:30-12:30 - Bibliothèque PCT - F3.04
      Rules and Tools for Efficient Enzyme Evolution, Recruitment and Discovery Based on Catalytic Promiscuity
      ‘Promiscuous' enzymes possess additional activities in addition to their native ones, challenging the textbook adage “one enzyme – one activity”. The observation of strong promiscuous activities in the alkaline phosphatase (AP) superfamily - where one active site can catalyse up to six chemically distinct hydrolytic (...)
    • Frédéric van Wijland (Laboratoire Matière et Systèmes Complexes, Université Paris 7 Denis Diderot)
      Lundi 20 février 11:30-12:30 - Bibliothèque PCT - F3.04
      How far from equilibrium is active matter ?
      Active Matter in 2016 encompasses such a broad range of systems that it is almost a challenge to define what's behind this terminology. One of the unifying characteristics to all active systems is that individual constituents convert an external continuous supply of energy into random motion. On a representative (...)
    • Alberto Rosso (LPTMS Orsay)
      Lundi 13 février 11:30-12:30 - Bibliothèque PCT - F3.04
      Spatio-temporal patterns in ultra-slow domain wall creep dynamics
      Manipulation and storage of information in magnetic, ferroic and spintronic materials heavily rests on the possibility to create domains and, especially, to govern their boundaries. The control of domain wall dynamics is of crucial importance and hinges on our ability to describe its basic nature ; so much that (...)
    • Guy-Bart Stan (Imperial College London, UK)
      Lundi 6 février 11:30-12:30 - Bibliothèque PCT - F3.04
      Shared resources and biomolecular feedback considerations for engineering of bacterial cells with improved robustness and performance
      In this talk I will give an overview of some of our research activities in the "Control Engineering Synthetic Biology" group, where we focus our efforts on developing foundational forward-engineering methods to mathematically model, control, and experimentally implement synthetic gene circuits and cellular systems (...)
    • Emmanuelle Gouillart (Surface du Verre et Interfaces, CNRS/Saint-Gobain, Aubervilliers)
      Lundi 30 janvier 11:30-12:30 - Bibliothèque PCT - F3.04
      Microstructure coarsening in phase-separated viscous liquids observed by in situ synchrotron microtomography
      Phase separation concerns a wide range of liquids, from polymers to glass melts. In the coarsening regime, the typical size of phase separated domains grows with time in order to reduce interfacial energy. The kinetics of coarsening [Bray2002] are determined by physical properties of the liquids, but also by the (...)
    • Jean-Louis Barrat (LiPhy, Grenoble)
      Lundi 23 janvier 11:30-12:30 - Bibliothèque PCT - F3.04
      Statistics of stress avalanches in deformed amorphous solids : insight from elastoplastic models
      Elastoplastic models [1] describe the deformation of amorphous solids through a simple lattice based implementation of the scenario identified in numerous experiments and simulations [2] : irreversible ”shear transformations”, take place in localized regions in the stressed material, and the corresponding stress (...)
    • Luca Cipelletti (Laboratoire Charles Coulomb, Montpellier)
      Lundi 16 janvier 11:30-12:30 - Bibliothèque PCT - F3.04
      The glass transition of soft colloids
      We use a combination of light and X-ray scattering, rheology, and numerical simulations to provide a comprehensive picture of the glassy dynamics in soft colloids. We observe a rapid growth of the structural relaxation time with volume fraction at equilibrium, which is nearly independent of particle softness, in (...)
    • Hervé Isambert (Institut Curie)
      Lundi 9 janvier 11:30-12:30 - Bibliothèque PCT - F3.04
      Learning causal networks with latent variables from multivariate information in genomic data
      Learning causal networks from large-scale genomic data remains challenging in absence of time series or controlled perturbation experiments. We have developed and implemented an information-theoretic method which learns a large class of graphical models from purely observational data. The approach unifies causal (...)
    • Anne-Florence Bitbol (Laboratoire Jean Perrin, UPMC)
      Lundi 2 janvier 11:30-12:30 - Bibliothèque PCT - F3.04
      Inferring interaction partners from protein sequences
      Specific protein-protein interactions play crucial roles in the stability of multi-protein complexes and in signal transduction. Thus, mapping these interactions is key to a systems-level understanding of cells. However, systematic experimental identification of protein interaction partners is still challenging, (...)
  • 2016

    • Emmanuel Fort (Institut Langevin, ESPCI)
      Lundi 12 décembre 2016 11:30-12:30 - Bibliothèque PCT - F3.04
      Time mirrors and temporal cavities
      Wave control is usually performed by engineering the spatial properties of the medium. Because space and time play similar roles, it is possible to perform time manipulations with a dual approach. In this talk, I will show how such manipulations enable one to obtain a “time reversal machine” for the waves. In (...)
    • Catherine Quilliet (LiPhy Grenoble)
      Lundi 5 décembre 2016 11:30-12:30 - Bibliothèque PCT - F3.04
      Shell deformation and swimming
      A spherical hollow object, isotropic and homogeneous at the scale of its radius (micronic in various examples to be found in Soft Matter, biology, or in miniaturized devices) is likely to present a diversity of shapes when its volume is decreased. Such an object being fruitfully modelled by a closed elastic (...)
    • Kirsten Martens (LiPhy Grenoble)
      Lundi 28 novembre 2016 11:30-12:30 - Bibliothèque PCT - F3.04
      Mesoscopic modeling - specific ingredients and emergent behaviours
      In this talk I will discuss several mesoscopic approaches, such as lattice models and mean-field descriptions for the yielding transition and the non-linear rheology of driven yield-stress materials. Despite the fact that this type of models require some phenomenological ingredients, notably the detailed local (...)
    • Denis Bartolo (ENS Lyon)
      Lundi 21 novembre 2016 11:30-12:30 - Bibliothèque PCT - F3.04
      Flocking through disorder
      How do flocks, herds and swarms proceed through disordered environments ? This question is not only crucial to the displacement of animal groups in the wild, but also to virtually all applications of collective robotics, and active materials composed of motile units. In stark contrast, appart from very rare (...)
    • Élisabeth Lemaire (LPMC, Nice)
      Lundi 14 novembre 2016 11:30-12:30 - Bibliothèque PCT - F3.04
      Rheology of non-Brownian concentrated suspensions : the role of contact forces between particles
      Creeping flows of non-Brownian suspensions are ubiquitous in industrial processes (charged polymers, fresh concrete, solid rocket propellants…) as well as in natural phenomena (sedimentary flows, landslides…). Even when the suspending fluid is Newtonian, these concentrated suspensions exhibit a complex rheology. For (...)
    • David Dean (LOMA Bordeaux)
      Lundi 7 novembre 2016 11:30-12:30 - Bibliothèque PCT - F3.04
      Stochastic Density Functional Theory for Electrolytes Out of Equilibrium
      The dynamics of interacting Brownian particles can be described by a stochastic equation for the density field. I will show how the linearised version of this equation can be used to recover, very simply, certain of Onsager's results on electrolyte conductivity. In addition I will show how it can analyse the out (...)
    • Aleksandra Walczak (LPT ENS)
      Lundi 24 octobre 2016 11:30-12:30 - Bibliothèque PCT - F3.04
      Diversity of immune repertoires
      Recognition of pathogens relies on the diversity of immune receptor proteins. Recent experiments that sequence the entire immune cell repertoires provide a new opportunity for quantitative insight into naturally occurring diversity and how it is generated. I will show how by applying statistical inference to these (...)
    • Chaouqi Misbah (LiPhy, Grenoble)
      Lundi 17 octobre 2016 11:30-12:30 - Bibliothèque PCT - F3.04
      Blood : flow, swimming and patterns
      Blood elements (like red blood cells=RBC) can either be transported by a flow or they can behave as active machines –amoeboid swimmers– (the case of leukocytes). In the first part, several rich dynamics and patterns of RBCs under flow will be described, such as "blood crystals" (spontaneous order of RBCs under pure (...)
    • Werner Krauth (LPS, ENS)
      Lundi 10 octobre 2016 11:30-12:30 - Bibliothèque PCT - F3.04
      Two-dimensional melting : New algorithms, new insights
      The hard-disk model has exerted outstanding influence on computational physics and statistical mechanics. Decades ago, hard disks were the first system to be studied by Markov-chain Monte Carlo methods (1) and by molecular dynamics (2). It was in hard disks, through numerical simulations, that a two-dimensional (...)
    • Alexander Leshansky (Technion, Israel)
      Lundi 3 octobre 2016 11:30-12:30 - Bibliothèque PCT - F3.04
      Dynamics of externally actuated magnetic propellers
      Technology based on magnetic micro-/nanopropellers that can be actuated remotely by a low strength rotating magnetic field and steered at high precision through various fluidics environments is considered attractive towards potential biomedical applications. Despite the substantial progress in microfabrication, (...)
    • Jean-Baptiste Fournier (Université Paris Diderot, Laboratoire MSC)
      Lundi 26 septembre 11:30-12:30 - Bibliothèque PCT - F3.04
      Hydrodynamics of bio-membranes
      After recalling the Stokes flow equations of ordinary viscous fluids, I will describe the original approach of Brochard and Lennon for the hydrodynamics of bio-membranes and red blood cells. Then I will discuss the more complete and rigorous theory of Seifert and Langer together with two applications : the (...)
    • Jean-Baptiste Fournier (Université Paris Diderot, Laboratoire MSC)
      Lundi 26 septembre 2016 11:30-12:30 - Bibliothèque PCT - F3.04
      Hydrodynamics of bio-membranes
      After recalling the Stokes flow equations of ordinary viscous fluids, I will describe the original approach of Brochard and Lennon for the hydrodynamics of bio-membranes and red blood cells. Then I will discuss the more complete and rigorous theory of Seifert and Langer together with two applications : the (...)
    • Gladys Massiera (L2C Montpellier)
      Lundi 19 septembre 2016 11:30-12:30 - Bibliothèque PCT - F3.04
      Continuous Droplet Interface Crossing Encapsulation (cDICE) : from vesicles to capsules
      The Continuous Droplet Interface Crossing Encapsulation (cDICE) is an easy and robust method for producing, at high yield, monodisperse lipid vesicles with a controlled content as well as capsules with a designed shell. It consists in forcing a droplet through an interface between two imiscible fluids, using an (...)
    • Sylvie Hénon (MSC Université Diderot)
      Lundi 12 septembre 2016 11:30-12:30 - Bibliothèque PCT - F3.04
      Passive and active mechanical properties of muscle cells. Role of desmin intermediate filament.
      The mechanical interactions of living systems with their environment play a central role both in healthy and pathological contexts. For instance, organs can feel and respond to the mechanical properties of their surroundings. This is particularly obvious for muscles. I will present our measurements of the (...)
    • Cécile Appert-Rolland (LPT Orsay)
      Lundi 5 septembre 11:30-12:30 - Bibliothèque PCT - F3.04
      Intracellular bidirectional transport of cargos by teams of motors
      Within cells, various objects (vesicles, organelles,...) need to be transported. Some processive molecular motors get attached to these objects (or cargos) to form a complex that will have a stochastic motion along a network of microtubules. Intriguingly, there is some evidence that this motion results from a (...)
    • Cécile Appert-Rolland (LPT Orsay)
      Lundi 5 septembre 2016 11:30-12:30 - Bibliothèque PCT - F3.04
      Intracellular bidirectional transport of cargos by teams of motors
      Within cells, various objects (vesicles, organelles,...) need to be transported. Some processive molecular motors get attached to these objects (or cargos) to form a complex that will have a stochastic motion along a network of microtubules. Intriguingly, there is some evidence that this motion results from a (...)
    • Anne Juel (University of Manchester, UK)
      Lundi 11 juillet 2016 11:30-12:30 - Bibliothèque PCT - F3.04
      Fingering Instabilities in Compliant Channels
      What links a baby's first breath to adhesive debonding, enhanced oil recovery, or even drop-on-demand devices ? All these processes involve moving or expanding bubbles displacing fluid in a confined space, bounded by either rigid or elastic walls. In this talk, we show how spatial confinement may either induce or (...)
    • Daniel Bonn (University of Amsterdam, The Netherlands)
      Lundi 4 juillet 2016 11:30-12:30 - Bibliothèque PCT - F3.04
      Granular Friction : from Building the Pyramids to the Anatomy of Individual Contacts at the Nanoscale
      I will discuss the rheology and mechanical properties of wet granular materials, and show why the behavior can be very subtle. Once one understands the mechanical properties, I will show that one can use this knowledge to construct the perfect sandcastle, or to understand why the ancient Egyptians wetted the (...)
    • Matthieu Wyart (EPFL, Switzerland)
      Lundi 27 juin 2016 11:30-12:30 - Bibliothèque PCT - F3.04
      Levy Flight in Mayonnaise
      Glassy systems with long-range interactions often present avalanche type-response under slow driving, as well as a vanishing density of excitation at low energy or “pseudo gap”. I will explain why these facts must come together, and discuss in particular the plasticity of amorphous solids (for example, how does a (...)
    • Kristina Davitt (LPS, ENS)
      Lundi 20 juin 2016 11:30-12:30 - Bibliothèque PCT - F3.04
      Contact Angle Hysteresis and Dynamics on Real Surfaces
      Real surfaces are rough, chemically heterogeneous, coated with molecular layers, or even all of the above. It is well known that liquid drops on such surfaces exhibit a contact angle hysteresis due to the pinning of the contact line. Over 30 years ago Joanny and de Gennes developed what is arguably still the best (...)
    • Alberto Fernandez-Nieves (Paris Sciences Chair & Georgia Tech, USA)
      Lundi 13 juin 2016 11:30-12:30 - Bibliothèque PCT - F3.04
      From Active Nematics on Tori to Fire Ants in the Rheometer
      We will discuss recent results with different types of active materials. We will begin by looking at active nematics on toroidal surfaces. We will illustrate defect unbinding and defect-curvature coupling, consistent with theoretical expectations for inactive ordered materials arranged on the surface a torus. In (...)
    • Christophe Goupil (PIERI, Université Paris Diderot)
      Lundi 6 juin 2016 11:30-12:30 - Bibliothèque PCT - F3.04
      Thermoelectricity : From Classical to Quantum Engines
      Thermoelectric effects result from the interference of electrical current and heat flow in various materials. This interaction, characterized by a coupling parameter called thermopower, allows direct conversion of heat to electricity ; conversely cooling may be obtained by application of a voltage across a (...)
    • Eric Bertin (LIPhy, Université Joseph Fourier, Grenoble)
      Lundi 30 mai 2016 11:30-12:30 - Bibliothèque PCT - F3.04
      On the Breaking of Energy Equipartition in Non-Equilibrium Systems
      Energy equipartition between degrees of freedom having a quadratic energy is a cornerstone of equilibrium statistical physics. In the presence of correlations, equipartition often applies to extended modes, like Fourier or normal modes, rather than to localized degrees of freedom. For systems driven out of (...)
    • David Ruelle (IHES, Bures-sur-Yvette)
      Lundi 23 mai 2016 11:30-12:30 - Bibliothèque PCT - F3.04
      Generalized Detailed Balance and Biological Applications
      A detailed balance relation is an identity based on time reversal symmetry of time evolution equations. This identity, which is part of statistical mechanics, relates the probability of an evolution J->K and the reverse evolution K->J. Ambitious applications of detailed balance to biological replication have been (...)
    • Cécile Cottin-Bizonne (ILM, Université Lyon I)
      Lundi 9 mai 2016 11:30-12:30 - Bibliothèque PCT - F3.04
      From Dilute to Dense Suspensions of Active Colloids
      Diffusiophoresis is an interfacially driven transport phenomenon, leading to the motion of macro-molecules under solute gradients. It is an efficient but rather unexplored mean to drive and manipulate particles. This energy transduction mechanism can also be used to device self-propelled particles. In this talk I (...)
    • Giulio Biroli (IPhT, CEA Saclay)
      Lundi 2 mai 2016 11:30-12:30 - Bibliothèque PCT - F3.04
      Breakdown of Elasticity in Amorphous Solids
      What characterises a solid is its way to respond to external stresses. Ordered solids, such crystals, display an elastic regime followed by a plastic one, both well understood microscopically in terms of lattice distortion and dislocations. For amorphous solids the situation is instead less clear, and the (...)
    • David Andelman (Tel Aviv University, Israel)
      Lundi 25 avril 2016 11:30-12:30 - Bibliothèque PCT - F3.04
      One Hundred Years of Electrified Interfaces : Past, Present and Future
      The Poisson-Boltzmann theory is a mean-field description of ionic solutions and charge interfaces, and it has been instrumental during the last century to predict charge distributions and interactions between charged macromolecules. While the electrostatic model of charged fluids, on which the Poisson-Boltzmann (...)
    • Stéphane Santucci (ENS Lyon)
      Lundi 18 avril 2016 11:30-12:30 - Bibliothèque PCT - F3.04
      Intermittent Avalanche Dynamics of Slow Imbibition Fronts
      I will review our experimental study of the dynamics of a viscous wetting fluid interface forced to invade a disordered medium –a model open fracture– at constant flow rate. Distortions of the advancing imbibition front produced by capillary pressure fluctuations (due to the heterogeneities of the medium) are damped (...)
    • Peter Schall (Joliot Chair & University of Amsterdam, The Netherlands)
      Lundi 4 avril 2016 11:30-12:30 - Bibliothèque PCT - F3.04
      Nonequilibrium Transitions Govern the Flow of Glasses
      The understanding of glasses remains one of the grand challenges in condensed matter : glasses have liquid-like structure, but exhibit solid-like properties. These materials inspire us to re-think the notion of flow and rigidity of solids. Recent theory and experiments suggest novel nonequilibrium transitions to (...)
    • Friedrich Simmel (TU Munich, Germany)
      Lundi 21 mars 2016 11:30-12:30 - Bibliothèque PCT - F3.04
      Molecular Devices Based on Nucleic Acids
      Over the past years, DNA nanotechnology has developed tremendously, and it is now possible to create nanoscale molecular devices of considerable complexity. After a general introduction to the field, we will here demonstrate a variety of machine-like devices based on DNA such as DNA-based membrane channels, large (...)
    • Emilie Dressaire (NYU, USA)
      Lundi 14 mars 2016 11:30-12:30 - Bibliothèque PCT - F3.04
      Fluid Flow on and in Complex Media
      In this talk, I will present experiments devoted to systems in which the couplings between the fluid and the surrounding medium lead to interesting flow dynamics. We will first consider the thin liquid films formed when jets impinge on solid surfaces such as hydraulic jumps and water bells. On a smooth surface, (...)
    • Jon Otto Fossum (Joliot Chair & NTNU, Norway)
      Lundi 7 mars 2016 11:30-12:30 - Bibliothèque PCT - F3.04
      Clay Physics
      In this talk, we will first give a very condensed introduction to the kind of soft and complex matter physics one can encounter in clays, by giving some illustrating highlights from our own and other group's scientific activities in this area. Secondly we will briefly review some known present and some maybe not (...)
    • Yannick Rondelez (University of Tokyo, Japan)
      Lundi 29 février 2016 11:30-12:30 - Bibliothèque PCT - F3.04
      In Vitro Models of Cellular Computing
      Living cells use webs of chemical reactions organized in precise networks to perform informational tasks. This concept is at the very core of systems biology, but also share links with electronic or computer science. The dynamical and information-processing properties of living cells, i.e. their ability to make (...)
    • Günter Reiter (Albert-Ludwig University of Freiburg, Germany)
      Lundi 22 février 2016 11:30-12:30 - Bibliothèque PCT - F3.04
      Transient Cooperative Processes in Dewetting Polymer Melts
      We have compared the high velocity dewetting behavior, at elevated temperatures, of atactic (aPS) and isotactic polystyrene (iPS) films, with the zero shear bulk viscosity (ηbulk) of aPS being 10 times larger than that of iPS. As expected, for aPS the apparent viscosity of the films (ηf) derived from dewetting was (...)
    • Adrien Benusiglio (LPS, ENS)
      Lundi 15 février 2016 11:30-12:30 - Bibliothèque PCT - F3.04
      Dancing Droplets (Marangoni Self-Contracted Self-Lubricated Volatile Droplets)
      When deposited on a clean glass slide, droplets of a mixture of propylene glycol and water of various concentrations enter a chaotic ballet for minutes, hence the name “dancing droplets”. Looking at one isolated droplet is already a surprise, as the mixture that should spread is instead stabilized by a gradient of (...)
    • Ludovic Berthier (Laboratoire Charles Coulomb, Université de Montpellier)
      Lundi 8 février 2016 11:30-12:30 - Bibliothèque PCT - F3.04
      Collective Motion in Dense Active Materials
      We discuss how the nonequilibrium driving forces introduced by the natural biological activity or by physical self-propulsion mechanisms generically affect the structure, dynamics and phase behavior of dense active media. We use theory and computer simulations to analyse simple models of such active materials. We (...)
    • Thierry Ondarçuhu (CEMES, Toulouse)
      Lundi 1er février 2016 11:30-12:30 - Bibliothèque PCT - F3.04
      AFM Study of Liquid Nanomenisci and Wetting of Partially Supported Graphene Monolayers
      The recent development of nanofluidics raises many questions about hydrodynamics and wetting at nanometer scale. I will present two experiments developed in CEMES to address these issues. I will show that that advanced FM-AFM techniques are promising tools for the investigation of mechanical properties of (...)
    • François Lequeux (SIMM, ESPCI)
      Lundi 25 janvier 2016 11:30-12:30 - Bibliothèque PCT - F3.04
      Role of Dynamical Heterogeneities in the Mechanics of Glassy Polymer
      Dynamical heterogeneities in glass - and peculiarly for polymer glasses - have been since more than 20 years the object of many debates. Nowadays, the actual picture is fairly simple ; glass can be considered as tiled by nanometric domains with very different dynamics. More precisely, the dynamics of the monomer (...)
    • Elisabeth Charlaix (LiPhy, Université Joseph Fourier, Grenoble)
      Lundi 18 janvier 2016 11:30-12:30 - Bibliothèque PCT - F3.04
      Hydrodynamic Forces : from Boundary Slippage to the Mechanics of Soft Surfaces
      Surface forces measurements have been an invaluable tool to perform quantitative mechanical probing at a nano-scale, and have contributed to our understanding of the friction of liquids onto solid surfaces and dissipation in confined liquid layers. But beyond the scope of friction, the measurement of (...)
    • Eric Lauga (DAMTP, University of Cambridge)
      Lundi 11 janvier 2016 11:30-12:30 - Bibliothèque PCT - F3.04
      Hydrodynamic Interactions between Flagellar Filaments
      Many small organisms possess flagella, slender whiplike appendages which are actuated in a periodic fashion in fluids and allow the cells to self-propel. In particular, most motile bacteria are equipped with multiple helical rotating flagella which interact hydrodynamically, synchronize, and can form a tight (...)
    • Detlef Lohse (Saint-Gobain Chair & University of Twente, Netherlands)
      Lundi 4 janvier 2016 11:30-12:30 - Bibliothèque PCT - F3.04
      Floating on Air
      A drop impacting on a solid surface deforms before the liquid makes contact with the surface. We directly measure the time evolution of the air layer profile under the droplet using high-speed color interferometry, obtaining the air layer thickness before and during the wetting process and the volume of the (...)
  • 2015

    • Jacco Snoeijer (University of Twente, Netherlands)
      Lundi 14 décembre 2015 11:15-12:15 - Bibliothèque PCT - F3.04
      Surface Tension Regularises the Crack Singularity of Adhesive Contacts
      Recent studies revealed a profound connection between “liquid wetting” and “solid adhesion” : both emerge as a limiting case for adhesion between sticky, elastic bodies. Here we address the unification of wetting and adhesion on the level of the contact mechanics. We first show that soft elastic bodies can exhibit a (...)
    • Ramin Golestanian (University of Oxford, UK)
      Lundi 7 décembre 2015 11:15-12:15 - Bibliothèque PCT - F3.04
      Collective Chemotaxis of Colloidal and Living Active Matter
      The non-equilibrium dynamics of active particles that send and receive chemical signals could lead to spontaneous formation of interesting structures and patterns due to the long-range nature of the interactions. I examine theoretically the consequences of this interaction, and present some results that exemplify (...)
    • Andreas Carlson (University of Oslo, Norway)
      Mardi 1er décembre 2015 11:00-12:00 - Bibliothèque PCT - F3.04
      Elastohydrodynamic Singularity and Self-similarity in Contacting Sheets
      The dynamics of contact between a thin elastic film and a solid arises in many scientific and engineering applications, from the simple saran-wrap to cellular adhesion to grounding lines in ice sheets. Elastohydrodynamic lubrication theory allows us to derive a partial differential equation coupling the elastic (...)
    • Frédéric Léchenault (LPS, ENS)
      Lundi 30 novembre 2015 11:15-12:15 - Bibliothèque PCT - F3.04
      Origami Mechanics
      Over the past thirty years, the ancient art of paper folding, or origami, has evolved into an interdisciplinary scientific field. Origami offers the possibility for new metamaterials whose overall mechanical properties can be programmed by acting locally on each crease. Origami metamaterials show for example (...)
    • Ullrich Steiner (Adolphe Merkle Institute, University of Friburg, Switzerland)
      Lundi 23 novembre 2015 11:15-12:15 - Bibliothèque PCT - F3.04
      Structure-Function Relationship in Polymer Solar Cells
      Organic solar cells typically consist of several components and it is long recognised that their efficiency depends on the detailed morphology of these constituents. Structure formation in two components systems, often containing a conjugated polymer and a C60 derivative, is currently not well understood and the (...)
    • Jérôme Casas (Paris Sciences Chair & Université de Tours)
      Lundi 16 novembre 2015 11:15-12:15 - Bibliothèque PCT - F3.04
      Flow Microsensors : From Insects to MEMS and Back
      Jérôme Casas, Paris Sciences Chair & Université de Tours I will start this talk by making a short excursion into the physical ecology of insects which we study with colleagues of the ESPCI and other physicists of similar spirit. I will then deal with the latest advances in our understanding of insect and man-made (...)
    • François Boulogne (Princeton University, USA)
      Lundi 9 novembre 2015 11:15-12:15 - Bibliothèque PCT - F3.04
      Homogeneous Deposition of Particles on Hydrogels by Absorption
      A drying drop containing solid particles like tea or coffee leaves a ring stain resulting from the accumulation of the particles near the contact line. In most of industrial applications such as printing, coating or biological microtechnologies, these inhomogeneities must be avoided. A significant range of new (...)
    • Pascal Martin (Institut Curie)
      Lundi 2 novembre 2015 11:15-12:15 - Bibliothèque PCT - F3.04
      Friction from Ion Channels' Gating on Vibrating Hair-Cell Bundles from the Inner Ear
      Hearing starts when sound-evoked mechanical vibrations of the hair-cell bundle activate mechanosensitive ion channels, giving birth to an electrical signal As for any mechanical system, friction impedes movements of the hair bundle and thus constrains the sensitivity and frequency selectivity of auditory (...)
    • Adrian Daerr (MSC, Université Paris Diderot)
      Lundi 26 octobre 2015 11:15-12:15 - Bibliothèque PCT - F3.04
      Wetting Dynamics and Mass Swarming of Bacillus Subtilis over Soft Gel Substrates
      Bacillus subtilis forms dendric colonies on gel surfaces through the collective motion of groups of 10^4 to 10^5 cells which form the compact tips of elongating dendrites. We investigate some physical aspects of this phenomenon, for which humidity and the surfactant production by the bacteria play as much of a (...)
    • Jörg Baschnagel (ICS, Université de Strasbourg)
      Lundi 19 octobre 2015 11:15-12:15 - Bibliothèque PCT - F3.04
      MD Simulation of Supercooled Polymer Melts : Modeling of Single-Monomer Dynamics by a Continuous-Time Random Walk Approach
      We present results of molecular-dynamics (MD) simulations for the dynamics of supercooled polymer melts. After an introduction to the simulation model and its ensemble-averaged properties, we analyze the dynamics of single-monomer trajectories. In the supercooled state near the critical temperature of (...)
    • Annie Colin (SIMM, ESPCI)
      Lundi 12 octobre 2015 11:15-12:15 - Bibliothèque PCT - F3.04
      Flow of Non-Brownian Suspension in Pipe
      Suspensions are ubiquitous in nature and are encountered in many applications : cement and concrete technology, ceramic processing, coating and pigment technology, propellants and explosives, mineral processing, soil science, composite processing and various slurry flow technologies. The rheological properties of (...)
    • Lionel Bureau (LIPhy, Université Joseph Fourier, Grenoble)
      Lundi 5 octobre 2015 11:15-12:15 - Bibliothèque PCT - F3.04
      The Physics of Stimuli-Responsive Polymer Brushes Probed with Optics
      Advanced functional substrates designed from polymer brushes have known a rapidly growing interest over the past fiteen years, with a particular attention paid to the elaboration of brushes made of stimuli-responsive polymers, in order to design smart surfaces whose properties can be altered on demand via the (...)
    • Hanneke Gelderblom (University of Twente, Netherlands)
      Lundi 28 septembre 2015 11:15-12:15 - Bibliothèque PCT - F3.04
      Propelling and Shaping Liquid Drops by Laser-Pulse Impact
      The impact of a laser pulse onto a liquid drop can be so violent that it leads to strong propulsion, deformation and eventually fragmentation of the drop. Here, we investigate how the drop response depends on the laser-pulse properties and drop characteristics by combining high-speed and stroboscopic imaging (...)
    • Karsten Kruse (Universität des Saarlandes, Germany)
      Lundi 21 septembre 2015 11:15-12:15 - Bibliothèque PCT - F3.04
      Spontaneous Actin Polymerization Waves and Cell Motility
      The crawling of living cells on solid substrates is often driven by the actin cytoskeleton, a network of structurally polar filamentous proteins that is intrinsically driven by the hydrolysis of ATP. How cells organize their actin network during crawling is still poorly understood. A possible general mechanism (...)
    • Etienne Rolley (LPS, ENS)
      Lundi 14 septembre 2015 11:15-12:15 - Bibliothèque PCT - F3.04
      Adsorption-Induced Strains of a Nanoscale Silicon Honeycomb
      Porous Silicon obtained from highly doped Si can be thought of as a nanoscale random honeycomb with pores parallel to the [001] axis. For about 10 years, this system has received renewed attention as a model system for adsorption studies. One of the intriguing features of this system is that the emptying of (...)
    • Frédéric Restagno (LPS, Université Paris-Sud)
      Lundi 7 septembre 2015 11:15-12:15 - Bibliothèque PCT - F3.04
      Polymer Brushes Dynamics in Melt, Sheared and Confined Situations
      End tethered polymer chains have been recognized to be excellent adhesion promoters at polymer interfaces provided that they can penetrate and interdigitate into the bulk polymer. As a consequence, tethered chain dynamics is of major importance to understand the mechanical answer of a polymer close to a surface. (...)
    • Soft Matter Days 2015
      From 2 July 2015 09:00 to 3 July 2015 17:50
    • Jean-François Lutz (Institut Charles Sadron, Strasbourg)
      Lundi 29 juin 2015 11:15-12:15 - Bibliothèque PCT - F3.04
      Unnatural Information-containing Macromolecules
      Information-containing macromolecules are polymers that contain a message encrypted in their comonomer sequences. The archetypal example of such a polymer is DNA, which is used in biology to store genetic information. However, DNA is certainly not the only polymer that can contain molecular information. In (...)
    • Tristan Baumberger (INSP, Paris VI)
      Lundi 22 juin 2015 11:15-12:15 - Bibliothèque PCT - F3.04
      Build-Up of a Thermoreversible Polymer Network : from Early Local to Late Collective Dynamics
      Thermoreversible polymer gels exhibit slow - logarithmic - mechanical strengthening. As is the case for many disordered systems, although this aging process is handwavingly ascribable to the “complexity of the energy landscape”, a more detailed understanding remains elusive. In order to gain some insight into the (...)
    • Martin Bazant (MIT, USA)
      Lundi 15 juin 2015 11:15-12:15 - Bibliothèque PCT - F3.04
      Control of Dendritic Growth in Electrodeposition
      For over 30 years, physicists have studied electrodeposition as a canonical example of fractal dendritic growth. The simplest model is Diffusion-Limited Aggregation (DLA), but electromigration, convection, and surface phenomena also play important roles. This talk will introduce the basic physics of (...)
    • Alberto Fernandez-Nieves (Paris Sciences Chair & Georgia Tech, USA)
      Lundi 8 juin 2015 11:15-12:15 - Bibliothèque PCT - F3.04
      Toroidal Droplets – Generation, Evolution in the Absence and in the Presence of Charge, Stabilization and Nematic Order
      We will describe our experiments on the generation, hydrodynamic stability and stabilization of toroidal droplets ; we will discuss both neutral and charged toroidal droplets. We will then focus on nematics and discuss how the toroidal confinement affects the director organization inside these spaces, both for (...)
    • Herbert Hui (Paris Sciences Chair & Cornell University, USA)
      Lundi 1er juin 2015 11:15-12:15 - Bibliothèque PCT - F3.04
      Surface Tension in Solids and its Effect on the Mechanics of Contact and Fracture
      Elasto-capillarity phenomena – solid deformation driven by liquid surface tension – have been extensively studied, but are distinct from phenomena driven by solid surface tension. The characteristic length scale that describes the deformation of a solid due to surface tension is given by the ratio between the (...)
    • Abdelhamid Maali (LOMA, Université de Bordeaux)
      Lundi 18 mai 2015 11:15-12:15 - Bibliothèque PCT - F3.04
      Dynamic AFM : Nano-Rheology of Confined Fluids
      In this talk I will present a study of the atomic force microscope (AFM) in liquid medium and its application to the study of the rheology of confined fluids. We will see that the AFM allows not only to image the surface of a substrate but also to measure the properties of the medium that is confined between the (...)
    • James Forrest (Total Chair & University of Waterloo, Canada)
      Lundi 11 mai 2015 11:15-12:15 - Bibliothèque PCT - F3.04
      Towards an Understanding of Glass Transitions in Thin Films
      For the past 20 years, there has been significant experimental, computational, and theoretical work on anomalous dynamics in thin films of glass forming polymers. Even considering only the single material, polystyrene (PS), the number of experiments, and the wide range of conclusions that have been reached from (...)
    • Karin Jacobs (Universität des Saarlandes, Germany)
      Lundi 4 mai 2015 11:15-12:15 - Bibliothèque PCT - F3.04
      Adhesion, Adsorption and Friction : Are Surface Phenomena Superficial ?
      As adhesion is a key issue for researchers of various fields, it is of uppermost importance to understand the parameters that are involved. Commonly, only surface parameters are employed to determine the adhesive forces between materials. Yet, van der Waals forces act not only between atoms in the vicinity of the (...)
    • Karin Sadoul (Institut Albert Bonniot, Grenoble)
      Lundi 27 avril 2015 11:15-12:15 - Bibliothèque PCT - F3.04
      Motor-Driven Marginal Band Coiling Promotes Cell Shape Change During Platelet Activation
      Boubou Diagouraga, Alexei Grichine, Arnold Fertin, Jin Wang, Saadi Khochbin and Karin Sadoul Circulating quiescent platelets have a flat, discoid shape maintained by a peripheral ring of microtubules, called the marginal band. Platelets are activated after vessel injury and undergo a major shape change known as (...)
    • Martin Lenz (LPTMS, Université Paris-Sud)
      Lundi 20 avril 2015 11:15-12:15 - Bibliothèque PCT - F3.04
      Disordered Actomyosin Contracts in Unexpected Ways
      The motion of living cells is in large part due to the interaction of semi-flexible actin filaments (F-actin) and myosin molecular motors, which induce the relative sliding of F-actin. It is often assumed that this simple sliding is sufficient to account for all actomyosin-based motion. While this is correct in (...)
    • Andrew Griffiths (LBC, ESPCI)
      Lundi 13 avril 2015 11:15-12:15 - Bibliothèque PCT - F3.04
      Droplet-based Microfluidics for Ultra-High-Throughput Digital Biology
      Programmable microfluidic modules have been created which can precisely make, combine, split, mix, incubate, detect fluorescence and sort microscopic droplets. Integration of multiple modules onto a single microfluidics chip enables a vast number of assays (> 105 / min) to be performed using extremely low volumes (...)
    • Fabian Brau (ULB, Belgium)
      Lundi 30 mars 2015 11:15-12:15 - Bibliothèque PCT - F3.04
      Morphogenesis, Self-Organization and Fracture in Elastic Thin Sheets
      When a curtain is suspended, a periodic deformation, having a given mean wavelength, is usually applied at one of its edges. This deformation relaxes along the curtain producing a cascade of folds characterized by an increase of the mean wavelength. We will show that this pattern can be understood as a (...)
    • Massimiliano Esposito (Joliot Chair & University of Luxembourg)
      Lundi 23 mars 2015 11:15-12:15 - Bibliothèque PCT - F3.04
      Nonequilibrium Thermodynamics of Closed and Open Chemical Networks
      I will present a systematic procedure to study the thermodynamics of chemical networks made of coupled elementary reactions satisfying mass action law. Convergence to equilibrium is proved in closed networks. In open networks (i.e. networks where concentrations of some of the species called chemostats are hold (...)
    • Basile Audoly (Institut d'Alembert, Paris VI)
      Lundi 16 mars 2015 11:15-12:15 - Bibliothèque PCT - F3.04
      Inextensible Elastic Ribbons : Models and Stability
      We consider the deformation of elastic ribbons, i.e. solids whose thickness is much smaller than the width, and whose width is much smaller than the length. A ribbon can typically be obtained by cutting out a strip in a piece of paper. From a mechanical perspective, the ribbon lies halfway between a (...)
    • Germain Rousseaux (Institut P', Poitiers)
      Lundi 9 mars 2015 11:15-12:15 - Bibliothèque PCT - F3.04
      The Naval Battle of Actium and the Myth of the Ship-Holder
      "The small Echeneis is present, wonderful to say, a great hindrance to ships." (Ovid, Halieutica)
    • David Gonzalez-Rodriguez (LadHyX, Polytechnique)
      Lundi 2 mars 2015 11:15-12:15 - Bibliothèque PCT - F3.04
      Cellular Morphodynamics : Shivering of Cellular Aggregates and Elasto-Capillary Instability of Mitochondria
      In this talk I will present two problems in cell mechanics where insight is gained through physical modeling and analogies to inert systems. First I will discuss our work on cellular aggregates, a simple laboratory model of tissues and tumors. We have studied the behavior of cellular aggregates under stretching (...)
    • Jean-Christophe Baret (CRPP, Université de Bordeaux)
      Lundi 23 février 2015 11:15-12:15 - Bibliothèque PCT - F3.04
      Soft Interfaces in Microfluidics
      Droplet-based microfluidics offers new means to miniaturize and automatize biochemical assays. The technology opens up on many applications in biotechnology, for example for single cell screening or molecular diagnostics. As the technology relies on emulsion manipulation in microchannels, it is crucial to (...)
    • François Pétrélis (LPS, ENS)
      Lundi 16 février 2015 11:15-12:15 - Bibliothèque PCT - F3.04
      Large Scale Dynamics and 1/f Fluctuations in Turbulence
      In a turbulent flow, many length scales contain energy. It is known for a long time that how the energy depends on the length scale is independent of details of the flow forcing or dissipation. Less in known about the temporal evolution of the turbulent field, in particular for the largest scales. I present a (...)
    • Olivier Pouliquen (IUSTI, Marseille)
      Lundi 9 février 2015 11:15-12:15 - Bibliothèque PCT - F3.04
      How Plants Feel Gravity : a Granular Flow Problem ?
      A plant accidentally put in a horizontal position rapidly bends and deforms to recover a vertical position. The ability of plants to feel gravity thus plays a key role in their development and adaptation to environmental changes (gravitropism). A crucial step in this gravisensing occurs in specific cells, the (...)
    • Christophe Poulard (LPS, Paris XI)
      Lundi 2 février 2015 11:15-12:15 - Bibliothèque PCT - F3.04
      Adhesion with a Cassie-Wenzel-like Transition for Textured Elastic Contacts
      When a smooth sphere of elastomer is pressed against a substrate micropatterned with a regular hexagonal array of pillars, a transition between a contact only established at the top of the pillars (Cassie-like state) and a mixed contact with a central zone of full contact (Wenzel-like state) surrounded by a top (...)
    • Anne-Dominique Cambou (EC2M, Gulliver, ESPCI)
      Lundi 26 janvier 2015 11:15-12:15 - Bibliothèque PCT - F3.04
      Geometry and Ordering in Crumpled Sheets
      Graphene membranes, cabbage leaves, and even the Himalayas are all examples of thin sheets : objects with a thickness much smaller than their length and width. Despite their differences in size and in material composition, similar patterns emerge when sheets are crumpled or forced into a small three-dimensional (...)
    • Mederic Argentina (INLN, Nice)
      Lundi 19 janvier 2015 11:15-12:15 - Bibliothèque PCT - F3.04
      Scaling Macroscopic Aquatic Locomotion
      Inertial aquatic swimmers that use undulatory gaits range in length L from a few millimetres to 30 metres, across a wide array of biological taxa. Using elementary hydrodynamic arguments, we uncover a unifying mechanistic principle characterizing their locomotion by deriving a scaling relation that links swimming (...)
    • Vincent Démery (PCT, Gulliver, ESPCI)
      Lundi 5 janvier 2015 11:15-12:15 - Bibliothèque PCT - F3.04
      Droplets Like to Wear Thin Polygonal Dresses
      A flat sheet must deform to wrap a liquid drop. Thin sheets (∼ 100 nm) wrap using small-scale wrinkles and folds, unlike thick sheets, which only bend over large scales. These features cost little mechanical energy but give considerable freedom to deform without stretching. We demonstrate that the global wrapped (...)
  • 2014

    • Jean-Christophe Géminard (Laboratoire de Physique, École Normale Supérieure de Lyon)
      Lundi 8 décembre 2014 11:15-12:15 - Bibliothèque PCT - F3.04
      Softening Induced Instability of a Stretched Cohesive Granular Layer
      First, we report on a cellular pattern which spontaneously forms at the surface of a thin layer of a cohesive granular material submitted to in-plane stretching. We then present a simple model in which the mechanism responsible for the instability is the ‘‘strain softening'' exhibited by humid granular materials (...)
    • Clément Vulin (MSC, Paris Diderot)
      Lundi 1er décembre 2014 11:15-12:15 - Bibliothèque PCT - F3.04
      A quantitative approach to microbial population growth using tailored cylindrical yeast colonies
      Microbes can form complex structures composed of millions to billions of cells. These assemblies contrast with the classical view we have of the “unicellulars” microbes. In fact, given their environment, they likely form heterogeneous connected structures, and our understanding of these assemblies is still scarce. (...)
    • Sergio Ciliberto (ENS Lyon)
      Lundi 24 novembre 2014 11:15-12:15 - Bibliothèque PCT - F3.04
      Information and thermodynamics : Experimental verification of Landauer's erasure principle
      Rolf Landauer argued that the erasure of information is a dissipative process . A minimal quantity of heat, proportional to the thermal energy, is necessarily produced when a classical bit of information is deleted. A direct consequence of this logically irreversible transformation is that the entropy of the (...)
    • Leticia Cugliandolo (Université Pierre et Marie Curie)
      Lundi 17 novembre 2014 11:15-12:15 - Bibliothèque PCT - F3.04
      Fast and slow quenches across second order phase transitions : the morphology of structures and the density of topological defects
      When a dissipative macroscopic system is driven through a second order phase transition (a quench) it undergoes an ordering process, usually called phase ordering. Typically, during this process, spatial regions with the order of the (competing) equilibrium phases increase in size and topological defects (be them (...)
    • Martin Brinkmann (Max Planck Institute, Allemagne)
      Lundi 10 novembre 2014 11:15-12:15 - Bibliothèque PCT - F3.04
      A multi particle collision algorithm for simulating immiscible multi-phase flows and wetting
      Interfacial displacement in porous media occurs in many natural processes and technological applications, ranging from filtering or fuel cells to secondary oil recovery and ground water management. Despite large advances in recent years the simulation of multi-phase flows in contact to heterogeneously wettable (...)
    • Thomas Gibaud (ENS Lyon)
      Lundi 3 novembre 2014 11:15-12:15 - Bibliothèque PCT - F3.04
      Hierarchical self-assembly of colloidal membranes
      Nature excels at building complex functional materials. We however are far from understanding the structure and mechanism involved in those materials and even further from being able to replicate equivalent materials. Here, we use stiff colloidal rods as minimalist building blocks to mimic biological structures (...)
    • Mathieu Leocmach (ENS, Lyon)
      Lundi 20 octobre 2014 11:15-12:15 - Bibliothèque PCT - F3.04
      Yoghurt under stress
      Biogels formed through the self-association of polysaccharide coils, collagen, actin filaments or attractive globular proteins play a major role in biochemistry and microbiology, biological networks and cell mechanics as well as in food science. Their mechanical properties are the physical basis of biomechanics (...)
    • Xavier Noblin (LPMC, Nice)
      Lundi 13 octobre 2014 11:15-12:15 - Bibliothèque PCT - F3.04
      Cavitation propagation in natural and artificial (microfabricated) systems
      The nucleation and growth of vapor bubble in a stretched liquid medium is a common phenomenon along boat helices. Main studies on cavitation in water under tension concern then hydraulics, but also acoustic or quasi-static conditions. These later are observed naturally in the sap conducting network of trees (...)
    • Mathieu Leocmach (ENS, Lyon)
      Lundi 6 octobre 2014 11:15-12:15 - Bibliothèque PCT - F3.04
      Yoghurt under stress
      Biogels formed through the self-association of polysaccharide coils, collagen, actin filaments or attractive globular proteins play a major role in biochemistry and microbiology, biological networks and cell mechanics as well as in food science. Their mechanical properties are the physical basis of biomechanics (...)
    • Axel Buguin (Institut Curie, Paris)
      Lundi 6 octobre 2014 11:15-12:15 - Bibliothèque PCT - F3.04
      Collective behaviors of bacteria
      Interacting biological cells can exhibit collective behaviors (clustering, migration…) that our knowledge at the scale of the single cell cannot fully explain. Such systems will be illustrated through experiments performed on chemotactic bacteria (Escherichia coli) swimming in liquid medium. Their behavior is (...)
    • Laurence Ramos (Laboratoire Charles Coulomb, Montpellier)
      Lundi 29 septembre 2014 11:15-12:15 - Bibliothèque PCT - F3.04
      Novel gels from wheat gluten proteins
      Wheat storage gluten proteins are among the most complex proteins families comprising at least fifty different proteins, with extremely broad polymorphisms. Wheat gluten proteins are moreover largely insoluble in water, rendering their study difficult. Gluten proteins are responsible for the remarkable (...)
    • Elisabeth Guazzelli (Aix-Marseille Université, CNRS, IUSTI UMR 7343)
      Lundi 22 septembre 2014 11:15-12:15 - Bibliothèque PCT - F3.04
      Dense suspension rheology, normal stresses, and migration
      Dense or highly concentrated particulate systems are very common in several engineering fields such as civil engineering, food or pharmaceutical industry as well as in geophysical situations such as debris flows, sediment transport, and submarine avalanches. The fundamental problem is to determine the response of (...)
    • Carlos Marques (Institut Charles Sadron, Strasbourg)
      Lundi 15 septembre 2014 11:15-12:15 - Bibliothèque PCT - F3.04
      Bio-adhesive lipid membranes on DNA carpets : confinement, depletion and localized pressure
      It has been recently shown[1] that when a bio-adhesive phospholipid vesicle is brought into contact with a carpeted surface of end-grafted lambda-phage DNAs, the spreading front of the adhesive patch propagates outwards from a nucleation center, acting as a scraper that strongly stretches the DNA chains. Moreover, (...)
    • Claire Wilhelm (Matière & systèmes complexes, Paris-Diderot, Université Paris Diderot)
      Lundi 8 septembre 2014 11:15-12:15 - Bibliothèque PCT - F3.04
      Magnetic nanoparticles as cellular labels : cell imaging, tissue engineering, fate and intercellular transfer.
      Cell therapies and medically oriented nanotechnologies are currently among promising biotechnologies. One promising approach is to associate magnetic nanoparticles with cells in order to supply them with sufficient magnetization to be detectable by MRI, manipulated by magnetic forces, or treated with therapeutic (...)
    • Gregory B. McKenna (Texas Tech University)
      Lundi 7 juillet 2014 11:15-12:15 - Bibliothèque PCT - F3.04
      Interrogating the physics of amorphous materials : Mechanics of materials from rubbery to glassy and from the macroscopic to the nanometric
      The mechanics of the materials in the world that surrounds us, at least from the time of Galileo, has fascinated humankind. In the present seminar I will describe our studies of the behavior of amorphous materials with special focus on the use of mechanical measurements to probe fundamental materials physics. (...)
    • Michael L. Falk (Johns Hopkins University, USA)
      Lundi 30 juin 2014 11:15-12:15 - Bibliothèque PCT - F3.04
      Nanoscale Models of Single Asperity Friction and Wear
      Understanding friction and wear behavior is limited in part by our lack of a detailed understanding of the atomic scale processes from which energy dissipation and material transfer arise. This has been particularly well illustrated by recent experiments, primarily employing atomic force microscopy (AFM), (...)
    • Christophe Blanc (Laboratoire Charles Coulomb, Montpellier)
      Lundi 23 juin 2014 11:15-12:15 - Bibliothèque PCT - F3.04
      Colloids trapped at complex liquid interfaces
      The physics of micron-sized particles trapped at liquid interfaces has been extensively studied from both fundamental and applied reasons. Model systems based on trapped microspheres have thus been used to study the physics of low-dimension systems. In the same time, colloidal particles are now commonly used in (...)
    • Pascal Damman (Laboratoire Interfaces & Fluides Complexes, Université de Mons, Belgique)
      Lundi 16 juin 2014 11:15-12:15 - Bibliothèque PCT - F3.04
      Patterns formation through elastic instabilities
      Hydrodynamics instabilities, such as B-enard-Marangoni convection, Rayleigh-Plateau, Rayleigh-Taylor and many others, are well known to produce beautiful patterns (see the book of F. Charru, Hydrodynamics Instabilities). Capillary, viscous and/or inertial forces conspire to generate very regular morphologies. In (...)
    • Sébastien Michelin (Ladhyx, École Polytechnique) : advective effects in the self-propulsion of autophoretic particles
      Lundi 2 juin 2014 11:15-12:15 - Bibliothèque PCT - F3.04
      Advective effects in the self-propulsion of autophoretic particles
      Autophoretic particles are able to self-propel in low-Reynolds-number flows using short range interactions between their surface and solute molecules produced or consumed by chemical reaction catalyzed at the particle's surface. The resulting motion is a fundamental example of synthetic particles achieving (...)
    • Yves Meheust (Geosciences Rennes) : Mixing and reaction kinetics in porous media : an experimental pore scale quantification
      Lundi 26 mai 2014 11:15-12:15 - Bibliothèque PCT - F3.04
      Mixing and reaction kinetics in porous media : an experimental pore scale quantification
      The mixing of chemical elements and nutrients is a primary controlling process for reactive transport in the subsurface, and consequently for biogeochemical cycles and contaminant transport in subsurface environments. Reaction kinetics measured in well-mixed laboratory reactors are never encountered on the field, (...)
    • Steve Plotkin (UBC Vancouver)
      Lundi 19 mai 2014 11:15-12:15 - Bibliothèque PCT - F3.04
      Generalizing Euclidean distance to understand polymer uncrossing and knotting : A physicist's foray into protein folding
      Physics often deals quite rightfully with symmetries and conservation laws, while molecular biology has historically retained little of this distinguished standard. Even the simplest biological macromolecules are aperiodic, have disordered energetics, and have enormously vast phase space relevant at biological (...)
    • Claire Wilhelm (Matière & systèmes complexes, Paris-Diderot) : annulé
      Lundi 12 mai 2014 11:15-12:15 - Bibliothèque PCT - F3.04
      Magnetic nanoparticles as cellular labels : cell imaging, tissue engineering, fate and intercellular transfer.
      Cell therapies and medically oriented nanotechnologies are currently among promising biotechnologies. One promising approach is to associate magnetic nanoparticles with cells in order to supply them with sufficient magnetization to be detectable by MRI, manipulated by magnetic forces, or treated with therapeutic (...)
    • Yves Méheust (Géosciences Rennes, Université Rennes 1) : séminaire reporté au 26 Mai
      Lundi 5 mai 2014 11:15-12:15 - Bibliothèque PCT - F3.04
      Mixing and reaction kinetics in porous media : an experimental pore scale quantification
      The mixing of chemical elements and nutrients is a primary controlling process for reactive transport in the subsurface, and consequently for biogeochemical cycles and contaminant transport in subsurface environments. Reaction kinetics measured in well-mixed laboratory reactors are never encountered on the field, (...)
    • Elise Lorenceau (Laboratoire Navier, Marne la Vallée)
      Lundi 28 avril 2014 11:15-12:15 - Bibliothèque PCT - F3.04
      Spontaneous oil suction by dry aqueous foams
      Detergency, food products, fire fighting or enhanced oil recovery are diverse examples that involve both aqueous foam and oil. Indeed, when using appropriate surfactants, oil and aqueous foam can be intimately mixed without destroying the foam. In most of the experimental studies concerning oils and foams, oil is (...)
    • Marco Rivetti (Max Planck Institute for Dynamics and Self-Organization, Göttingen)
      Lundi 14 avril 2014 11:15-12:15 - Bibliothèque PCT - F3.04
      Capillary driven deformations of elastic solids
      Surface tension plays a crucial role in designing the shape of liquid interfaces, like drops or bubbles, especially at small scales. Whenever a liquid interface is put in contact with a soft solid, capillary forces may be strong enough to induce deformations of the solid. In some configurations these deformations (...)
    • Rudolf Podgornik (Ljubljana, Slovenia) : DNA-protein interactions in virus-like nano-particles
      Lundi 7 avril 2014 11:15-12:15 - Bibliothèque PCT - F3.04
      DNA-protein interactions in virus-like nano-particles
      I will present recent experimental results and their theoretical framework on DNA packing in viro, i.e. inside virus capsids and virus-like nanoparticles. I will present some examples of the interaction between the nucleic acids and the proteinaceous envelope in viruses. Confined polyelectrolyte theory and nematic (...)
    • Emmanuelle Rio (LPS, UMR 8502, Université Paris Sud)
      Lundi 31 mars 2014 11:15-12:15 - Bibliothèque PCT - F3.04
      Generation and bursting of vertical soap films
      If a frame is pulled out of a soapy solution, a colored ephemeral free standing film will be created. How thick is this film and how long will it last ? These are the two questions we will address. We first show that the film is composed of two zones : a zone of well-defined thickness at the bottom and a thinning (...)
    • Antonin Eddi (PMMH, ESPCI)
      Lundi 24 mars 2014 11:15-12:15 - Bibliothèque PCT - F3.04
      Coalescence of drops on a substrate
      When two drops come into contact they will rapidly merge and form a single drop. Here we address the coalescence of drops on a substrate — an elementary process encountered for example during condensation and inkjet printing. We focus on the dynamics just after contact, by characterizing the growth of the thin (...)
    • Ian Williams (Soft Matter Chemistry, University of Bristol)
      Lundi 17 mars 2014 11:15-12:15 - Bibliothèque PCT - F3.04
      Hard Discs in Circular Confinement
      The behaviour of materials under spatial confinement is dramatically different from that in the bulk. The exact nature of behavioural modification in confined systems is strongly dependent on the boundary enclosing the system with soft walls inducing different phenomena than similar hard walls. In two dimensions, (...)
    • Marjolein van der Linden (ESPCI, Gulliver)
      Lundi 10 mars 2014 11:15-12:15 - Bibliothèque PCT - F3.04
      Formation and crystallisation of long-range repulsive colloidal glasses
      We studied long-range repulsive glasses formed in suspensions of sterically stabilised charged colloidal poly(methyl methacrylate) particles (diameter = 2.23 µm) with low polydispersity (4%) in the low-polar solvent cyclohexyl bromide (dielectric constant = 7.92). Particle interactions were described by a (...)
    • Georges Debregeas (Laboratoire Jean Perrin, UPMC/CNRS)
      Lundi 3 mars 2014 11:15-12:15 - Bibliothèque PCT - F3.04
      Brain-wide recording of neural activity at single-cell resolution using SPIM-based calcium imaging
      The optical transparency and the small dimensions of zebrafish at the larval stage make it a vertebrate model of choice for brain-wide in-vivo functional imaging. However, current point-scanning imaging techniques, such as two-photon or confocal microscopy, impose a strong limit on acquisition speed which in turn (...)
    • Raph Seemann (Universität des Saarlandes, Allemagne)
      Lundi 17 février 2014 11:15-12:15 - Bibliothèque PCT - F3.04
      From Foams to Phonons : Dynamic reorganizations of droplet arrangements
      Droplet based microfluidics is well known for high throughput screening and the fabrication of special materials. But droplet based microfluidics also offers a convenient environment to study complex dynamics of dissipative, non-equilibrium many bodies systems as the droplet density and droplet confinement can be (...)
    • Anne-Virginie Salsac (UTC, Compiègne)
      Lundi 10 février 2014 11:15-12:15 - Bibliothèque PCT - F3.04
      Fluid structure interaction of a microcapsule in flow
      A capsule consists of an internal medium enclosed by a semi-permeable membrane that controls exchanges between the environment and the internal contents and has a protection role. Natural capsules are cells, bacteria or eggs. Artificial capsules are widely used in industry (pharmaceutical, cosmetic, food industry, (...)
    • Hugues Bodiguel (LOF, Bordeaux)
      Lundi 3 février 2014 11:15-12:15 - Bibliothèque PCT - F3.04
      Flow of polymer solutions in porous media : rheology, slippage, confinement and turbulence
      Polymer solutions are used to control biphasic flows in porous media since by increasing the viscosity they tend to prevent fingering and to smooth the permeability heterogeneities. However, several additional phenomena need to be considered, such as non-linear rheology, elasticity and violation of the no-slip (...)
    • Anne Tanguy (Institut Lumière Matière, Lyon)
      Lundi 27 janvier 2014 11:15-12:15 - Bibliothèque PCT - F3.04
      Disorder and Acoustic Properties : the vibrations as predictors for plastic damage in glasses
      The mechanical response of glasses is full of unexplained properties, like the composition dependence of its plastic response. In this talk, we will first review the elasto-plastic response of amorphous materials, and then focus on their vibrational properties. The propagation of vibrations in disordered materials (...)
    • Laurent Ponson (UPMC, Paris)
      Lundi 20 janvier 2014 11:15-12:15 - Bibliothèque PCT - F3.04
      Designed pinning of peeling fronts in thin film adhesives
      Thin film adhesives are ubiquitous in our daily life, and they have become increasingly important in various applications such as packaging and coating. Despite their apparent simplicity, these systems can reveal a wide range of behaviors resulting from the complex interplay between the deformations of the elastic (...)
    • Patrick Guenoun (LIONS, CEA-Saclay)
      Lundi 13 janvier 2014 11:15-12:15 - Bibliothèque PCT - F3.04
      The shape and permeability of polymersomes
      Polymer vesicles, also named polymersomes, are valuable candidates for drug delivery and micro- or nanoreactor applications. As far as drug delivery is concerned, the shape of the carrier is believed to have a strong influence on the biodistribution and cell internalization. Polymersomes can be submitted to an (...)
    • Bruno Andreotti (labo PMMH, ESPCI & Prof. Paris-Diderot)
      Lundi 6 janvier 2014 11:15-12:15 - Bibliothèque PCT - F3.04
      Rigidity transition in amorphous media
      Contrarily to cristalline solids, amorphous media (glasses, emulsions, granular media, suspensions, foam, etc) do not present any long range translational order. However, they can resist shear and therefore behave mechanically as solid materials. To make them flow as a liquid, one has, depending on the material, (...)
  • 2013

    • Pascal Hersen (Matière & systèmes complexes, Paris ; Mechanobiology Institute, Singapore)
      Lundi 16 décembre 2013 11:15-12:15 - Bibliothèque PCT - F3.04
      Real time control of gene expression in yeast
      Gene expression plays a central role in the orchestration of cellular processes. The use of inducible promoters to change the level of expression of a gene from its physiological level has significantly contributed to understanding the functioning of many regulatory networks. Here, we show that by implementing an (...)
    • Catherine Barentin (Institut Lumière Matière, Lyon)
      Lundi 9 décembre 2013 11:15-12:15 - Bibliothèque PCT - F3.04
      Wetting and confined flows of yield stress fluids
      Foams, emulsions, polymer gels are example of every day life yield stress fluids. What makes such systems particularly interesting for applications, but fundamentally difficult to describe, is their intermediate fluid / solid behaviour : at rest they behave like an elastic solid, but they are able to flow like a (...)
    • Robert E. Cohen (MIT, USA)
      Lundi 2 décembre 2013 11:15-12:15 - Bibliothèque PCT - F3.04
      Design of Network Structures for Fog Harvesting and Other Applications
      Fog represents a largely unexploited source of potable drinking water. Fog harvesting nets have been used with various degrees of success in more than fifteen countries around the world. In the Atacama Desert in Northern Chile where MIT and Pontifical University of Chile Santiago have an active fog harvesting (...)
    • Maxime Dahan (Institut Curie)
      Lundi 25 novembre 2013 11:15-12:15 - Bibliothèque PCT - F3.04
      Probing the target search of individual DNA-binding proteins in mammalian cells
      For many cellular functions, DNA-binding proteins (DBPs) need to find specific target sites in the genome. Facilitated diffusion (FD), namely the combination of one-dimensional motion along non-specific DNA and three-dimensional exploration, is the dominant model for the target search (TS) of DBPs. Yet, this model (...)
    • Cécile Monteux (ESPCI, PPMD-SIMM)
      Lundi 4 novembre 2013 11:15-12:15 - Bibliothèque PCT - F3.04
      Reactive liquid interfaces
      Our goal is to control the properties of liquid interfaces (stability of a foam, spreading of a liquid on a surface) by using ‘reactive' amphiphilic molecules. I will give two examples : Photo-responsive bubbles, films and foams. We use surfactants which change their shape under UV light. The light intensity (...)
    • Antonio Celani (Institut Pasteur)
      Lundi 21 octobre 2013 11:15-12:15 - Bibliothèque PCT - F3.04
      The hidden hallmarks of nonequilibrium
      Systems with disparate timescales are ubiquitous in physics and biology. Efficient modeling requires to restrict the description to the slower degrees of freedom by means of a systematic, controlled elimination of fast variables. I will discuss this general issue in stochastic systems with multiple timescales. I (...)
    • A. J. Hudspeth (Rockefeller University)
      Lundi 7 octobre 2013 11:15-12:15 - Bibliothèque PCT - F3.04
      Mechanical amplification in the inner ear
      The ear is not a passive receiver of sound ; an active process instead endows our hearing with its remarkable features. The active process amplifies sounds by more than a hundredfold, greatly enhancing our sensitivity to weak stimuli. The ear's intrinsic amplifier additionally tunes our responsiveness to specific (...)
    • Hugo Jacquin (ENS Lyon)
      Lundi 30 septembre 2013 11:15-12:15 - Bibliothèque PCT - F3.04
      Static and dynamic theories of the glass and jamming transitions
      The glass and jamming transitions are two distinct mechanism by which atomistic (for the glass transition) and granular (for the jamming transition) systems acquire rigidity on a laboratory time scale. Although the glass and jamming physics are quite old subjects, the development of quantitative theories has been (...)
    • Mathieu Leocmach (ENS Lyon)
      Lundi 23 septembre 2013 11:15-12:15 - Bibliothèque PCT - F3.04
      Roles of icosahedral and crystal-like order in hard spheres glass transition
      A link between local structural ordering and slow dynamics has recently attracted much attention from the context of the origin of glassy slow dynamics. There have been a few candidates for such structural order, icosahedral order, exotic amorphous order, and crystal-like order. Each type of order is linked to a (...)
    • Fritz Vollrath (Oxford University)
      Lundi 16 septembre 2013 11:15-12:15 - Bibliothèque PCT - F3.04
      Unravelling Spider' Silks
      In silks, proteins are the structural components and water is the solvent. Protein and water combine and separate - under ambient pressures and temperatures - to make the silk thread, which can be so tough that it outperforms even the best man-made fibres. Spider silk is a case in point for outstanding mechanical (...)
    • François Graner (MSC, Université Denis Diderot, Paris)
      Lundi 9 septembre 2013 11:15-12:15 - Bibliothèque PCT - F3.04
      Dynamics of cellular materials : from foams to biological tissues
      Liquid foams are made of gas bubbles surrounded by water. They are model systems to understand complex cellular materials (made of cells tiling the space), which behave simultaneously as solids and liquids. We have established tools to link the discrete description, at the bubble scale, with a continuous (...)
    • Raphaël Voituriez (LPTMC)
      Lundi 1er juillet 2013 11:15-12:15 - Bibliothèque PCT - F3.04
      First-passage statistics and search strategies
      How long does it take a "searcher" to reach a "target" for the first time ? This first-passage time is a key quantity for evaluating the kinetics of various processes, and in particular chemical reactions involving "small" numbers of particles such as gene transcription, or at larger scales the time needed for (...)
    • Zoya Ignatova (Institute of Biochemistry and Biology, University of Potsdam, Germany)
      Lundi 24 juin 2013 11:15-12:15 - Bibliothèque PCT - F3.04
      Non-uniform speed of translation : Stochastic fluctuations or programmed pausing
      Translation of the genetic information from a nucleotide sequence into a functional protein is an essential biological process. The translation machinery, the ribosome, is a central player that translates the genetic information stored in the messenger RNA codon by codon. Multiple auxiliary factors with different (...)
    • Alan Needleman (University of North Texas)
      Lundi 17 juin 2013 11:15-12:15 - Bibliothèque PCT - F3.04
      Identifying Material Properties from Mechanical Tests
      Material behavior is quantified in terms of a set of “material properties” with a material property being a value, function or functional that can be used to predict responses under a variety of conditions. What constitutes a material property depends on the theory employed. For example, for isotropic linear (...)
    • James A. Forrest (University of Waterloo, Canada)
      Lundi 10 juin 2013 11:15-12:15 - Bibliothèque PCT - F3.04
      Dynamical and Mechanical Properties of Glassy Surfaces
      In this talk I will present a number of different approaches we have used to study the surface properties of glassy materials. Atomic force microscopy is used to measure the evolution of the surface of glassy materials (both polymeric and non-polymeric) after it is exposed to different perturbations. One such (...)
    • Vincenzo Vitelli (Instituut-Lorentz, Leiden, The Netherlands)
      Lundi 3 juin 2013 11:15-12:15 - Bibliothèque PCT - F3.04
      Shear front propagation and rheology in random elastic networks
      A minimal model for studying the mechanical properties of polymer networks, gels, granular media and glasses is a disordered network of point masses connected by harmonic springs. At a critical value of its mean connectivity, such a network becomes fragile : it undergoes a rigidity transition signaled by a (...)
    • Wiebke Drenckhan (LPS, Orsay)
      Lundi 27 mai 2013 11:15-12:15 - Bibliothèque PCT - F3.04
      And if all bubbles were equal ? Science and applications of monodisperse foams
      Sticking bubbles of equal volume together provides a simple system with complex properties which raise a number of fundamental scientific questions. Into what kind of structures do the bubbles organise themselves and why ? How do these arrangements deform under gravity ? And how can we generate them ? In bridging (...)
    • Jean-Marc di Meglio (MSC, Paris)
      Lundi 29 avril 2013 11:15-12:15 - Bibliothèque PCT - F3.04
      Contrôle de la locomotion chez le ver nématode C. elegans
      La capacité à se déplacer est très certainement une des propriétés les plus remarquables de la matière vivante. Cette capacité s'est déclinée au cours de l'évolution sur des modes multiples selon la taille, la forme des individus, et selon leur milieu ou leur habitat. Certains animaux ont même acquis la possibilité de (...)
    • Olivier Couture (ESPCI/Institut Langevin)
      Lundi 22 avril 2013 11:15-12:15 - Bibliothèque PCT - F3.04
      Injectable agents for the detection and treatment of cancer by ultrasound
      The Institut Langevin has developed an expertise on the manipulation of waves to improve ultrasound therapy within the brain, measure the elasticity of tissue and perform functional brain imaging. My particular field is concerned with injectable agents that are used to improve the capabilities of ultrasound for (...)
    • Camille Duprat (PMMH, ESPCI)
      Lundi 15 avril 2013 11:15-12:15 - Bibliothèque PCT - F3.04
      Elastocapillary flows
      The deformation of elastic structures under capillary forces (elastocapillarity) and their interaction with fluid flow (elastohyrodynamics), are important in many biological, geophysical and engineering processes. To understand these phenomena, I propose three model systems of elastocapillary flows that will be (...)
    • Lydéric Bocquet (Université Lyon 1)
      Lundi 8 avril 2013 11:15-12:15 - Bibliothèque PCT - F3.04
      Fluid transport at the nanoscales and blue energy harvesting
      « There is plenty of room at the bottom ». This visionary foresight of R. Feynman, introduced during a lecture at Caltech in 1959, was at the root of numerous scientific and technological developments, taking benefit of the "strange phenomena" occuring at the smallest scales. There remains however a lot to explore, (...)
    • Giovanni Cappello (Institut Curie, Paris)
      Lundi 25 mars 2013 11:15-12:15 - Bibliothèque PCT - F3.04
      Mechanics and tumor growth}
      Two key elements control the proliferation of tumors. On the one hand, cancer cells accumulate gene mutations. On the other hand, tumors have to interact with neighboring cells and to push on their surrounding in order to grow. Therefore, mechanical stress is one of the important parameters that have to be taken (...)
    • Christophe Josserand (Institut d'Alembert)
      Lundi 18 mars 2013 11:15-12:15 - Bibliothèque PCT - F3.04
      Wave turbulence in vibrating plates
      The concept of wave turbulence has been introduced about 50 years ago in the context of water waves. It consists in an asymptotic expansion of the cumulant terms of the dynamics that leads eventually to a kinetic equation. Beside the thermodynamical equilibrium solutions, this kinetic equation exhibits the (...)
    • Julien Deseigne (ENS Lyon)
      Lundi 25 février 2013 11:15-12:15 - Bibliothèque PCT - F3.04
      Molecular transport phenomenon of particles and mixing : building blocks of experimental ecology in oceans ?
      The chaotic laminar advection of colloids in presence of salt is investigated experimentally with microfluidic technology. As long as salt contrasts hold, colloids are carried along saline gradients much faster than the brownian motion. At larger scale, such synergy between salt and colloids give non trivial (...)
    • Stephan Fauve (LPS, ENS, Paris)
      Lundi 18 février 2013 11:15-12:15 - Bibliothèque PCT - F3.04
      Reversals of a magnetic field generated by a dynamo process
      Magnetic fields of many planets and stars are generated by a dynamo process, i.e. by electromagnetic induction due to the motion of an electrically conducting fluid. They often display reversals : the magnetic field flips between two states of opposite polarities. This occurs roughly periodically for the solar (...)
    • Maxime Clusel (Laboratoire Charles Coulomb, Montpellier)
      Lundi 11 février 2013 11:15-12:15 - Bibliothèque PCT - F3.04
      A Granocentric viewpoint on random packing of spheres
      I will present and discuss a simple statistical model for the random packing of frictionless, originally introduced to find the link between polydispersity and packing structure. We simplify the problem by considering the “granocentric” point of view of a single particle in the bulk, thereby reducing random packing (...)
    • Dominique Langevin (LPS, Orsay)
      Lundi 4 février 2013 11:15-12:15 - Bibliothèque PCT - F3.04
      Shear rheology of two-dimensional solids
      Many soft solids, such as concentrated suspensions, emulsions, foams, behave in a similar way under an applied shear : they exhibit a Maxwell-type relaxation with a characteristic relaxation time that varies inversely with the applied shear rate. When the storage and loss moduli are measured at different (...)
    • Jean-François Allemand (LPS, ENS, Paris)
      Lundi 28 janvier 2013 11:15-12:15 - Bibliothèque PCT - F3.04
      Some single molecule approaches to DNA replication
      DNA replication is an essential step of the cell cycle. Despite many biochemical studies, physical approaches can still bring new informations on some process of DNA replication. In vitro, using micromanipulation tools, we have shown that force can trigger some DNA polymerases into an exonuclease mode where (...)
    • Alba Marcellan (PPDM-SIMM, ESPCI)
      Lundi 21 janvier 2013 11:15-12:15 - Bibliothèque PCT - F3.04
      Nano-hybrid gels : from pure chemical to hybrid networks
      Nano-hybrid hydrogels combine a poly(N,N-dimethylacrylamide) covalent network and physical interactions by strong adsorption of polymer chains at the nanoparticle surface. The resulting mechanical behavior of such highly stretchable nano-hybrid hydrogels highlighted a very unusual combination of properties induced (...)
    • Jean-Louis Barrat (Université Joseph Fourier, Grenoble)
      Lundi 14 janvier 2013 11:15-12:15 - Bibliothèque PCT - F3.04
      Investigating mechanical properties of disordered solids with computer simulations
      Many solids around us are disordered : glassy or semi crystalline polymers, oxide or metallic glasses, nanocomposites, are common examples. In disordered systems, the link between macroscopic mechanical properties and the nanostructure of the materials is far from being understood. I will describe some of the (...)
    • Sascha Hilgenfeldt (University of Illinois at Urbana Champaign, USA)
      Lundi 7 janvier 2013 11:15-12:15 - Bibliothèque PCT - F3.04
      Understanding and manipulating microbubble streaming flows : size-sensitive sorting and mixing
      Ultrasound-induced oscillation of microbubbles gives rise to intense, steady streaming flows. We show that the flow patterns can be flexibly and interactively shaped by the superposition of a transport flow and adjustment of driving amplitude and/or frequency. In this way, sensitive selection, focusing, and (...)
  • 2012

    • Hirokazu Tanimoto (Institut Curie)
      Lundi 17 décembre 2012 11:15-12:15 - Bibliothèque PCT - F3.04
      A simple force-motion relationship of migrating cells
      In this talk, we would discuss about a force-motion relationship of migrating eukaryotic adherent cells. Biological cells migrate without net forces, which is a consequence of force-free and negligible inertia conditions (Purcell, 1977). This indicates that to elucidate a force-motion relationship, unlike in cases (...)
    • Séminaire : Karim Benchenane (Laboratoire de neurobiologie, ESPCI)
      Lundi 10 décembre 2012 11:15-12:15 - Bibliothèque PCT - F3.04
      Role of sleep in memory processes
      The two-stage model of memory consolidation developed by Gyorgy Buzsaki proposed that encoding occurs during awake hippocampal theta oscillations (5-10Hz) and consolidation during slow wave sleep (SWS), involving reactivations that occur during hippocampal 200Hz oscillations called the sharp-waves-ripples (...)
    • John F. Brady (California Institute of Technology, USA)
      Lundi 3 décembre 2012 11:15-12:15 - Bibliothèque PCT - F3.04
      Chemical Swimming
      The design of nanoengines that can convert stored chemical energy into motion is an important challenge of nanotechnology, especially for engines that can operate autonomously. Recent experiments have demonstrated that it is possible to power the motion of nanoscale and microscale objects by using surface (...)
    • James R. Rice (Harvard University)
      Lundi 19 novembre 2012 11:15-12:15 - Bibliothèque PCT - F3.04
      Dynamics and hydrology of rapid ice sheet motion
      Two questions are discussed which arise in evaluating possible scenarios of accelerated deglaciation in Greenland and Antarctica. A first question is, how fast can a glacier imbibe a meltwater lake, and what are the aftereffects ? It focuses on Greenland where, as spring commences, a broad swath of more (...)
    • Lev Truskinovsky (Ecole Polytechnique, Palaiseau, France)
      Lundi 12 novembre 2012 11:15-12:15 - Bibliothèque PCT - F3.04
      Equilibrium and non-equilibrium statistical physics of the power stroke in skeletal muscles
      The classical Huxley-Simmons model of muscle contractions exhibits unusual statistical properties due to the presence of long range elastic interactions. Those include non-equivalence of the soft and hard device ensembles, negative equilibrium stiffness and anomalously slow kinetics in the soft device. Our data (...)
    • Oliver Baeumchen (McMaster University,Hamilton, Canada)
      Lundi 5 novembre 2012 11:15-12:15 - Bibliothèque PCT - F3.04
      Can Polymers Slide ? New Insights from Capillary-Driven Flows in Thin Films
      The motion of small amounts of liquid on the micro- and nanoscale is of enormous scientific interest and additionally holds great technological potential, e.g. in lab-on-a-chip applications for pharmaceuticals, biological analysis or chemical reactions. When downsizing devices, interfacial and confinement effects (...)
    • Fernando Peruani (Universite de Nice Sophia Antipolis)
      Lundi 29 octobre 2012 11:15-12:15 - Bibliothèque PCT - F3.04
      From bacteria to collective motion in heterogeneous media
      First part - I will show some recent experimental results with three mutants of the gliding bacterium Myxococcus xanthus. We found that mutants lacking biochemical signaling and moving unidirectionally exhibit collective motion in the form of large moving clusters at intermediate densities, while self-organize (...)
General recommendations for the speakers

The audience is often heterogeneous - because of the wide range of scientific topics covered in the lab - so prefer planning a talk for a broad audience. It is recommended to spend several slides on a general introduction, and to make at least the first half of the seminar understandable for non-specialists. The seminar is in English, and speakers are thus invited to prepare their slides in English.

The seminar starts at 11:15 AM. The speaker is asked to arrive in the lab at least 15 minutes in advance to set up the slideshow. The talks last typically 45 minutes, and are followed by a discussion time.

Top

Practical information

ESPCI Administrator: Stéphanie Ledoux
Tél. : 01 40 79 47 39
stephanie.ledoux (arobase) espci.fr

CNRS Administrator: Solange Rogue
Tél. : 01 40 79 47 27
solange.rogue (arobase) espci.fr

Director: Elie Raphaël
Tél. : 01 40 79 46 00
elie.raphael (arobase) espci.fr

Assistant Director: Olivier Dauchot
Tél. : 01 40 79 58 42
olivier.dauchot (arobase) espci.fr

Visit us