- Published on 14 October 2013
First study to shows specific sounds’ speed and attenuation characteristics in liquid foam, opens the door to new type of sound proofing material
Liquid foams fascinate toddlers singing in a bubble bath. Physicists, too, have an interest in their acoustical properties. Borrowing from both porous material and foam science, Juliette Pierre from the Paris Diderot University, Paris, France and her colleagues studied liquid foams. They used an impedance tube to measure the velocity and attenuation of acoustic waves in liquid foams in a broad frequency range. The study published in EPJ E is a first in the literature. It could help in assessing any liquid foam’s bubble size or in designing the optimal foam structure for sound proofing.
- Published on 01 October 2013
How fluid dynamics and transport shaped the structure of our lungs in the course of evolution.
Two French physicists, Bernard Sapoval and Marcel Filoche from École Polytechnique in Palaiseau, France, suggest in a study published in EPJ E how evolution has shaped our lungs through successive optimisations of physical parameters such as conservation of energy and speed of delivery.
- Published on 25 September 2013
A new simulation will help improve artificial sand-control measures designed to help combat desertification by identifying their weaknesses
In the fight against desertification, so-called straw checkerboard barriers (SCB), consisting of half -exposed criss-crossing rows of straw of wheat, rice, reeds, and other plants, play a significant role. The trouble is that our understanding of the laws governing wind-sand movement in SCB and their surrounding area is insufficient. Now, Ning Huang and colleagues from Lanzhou University in China, have performed a numerical simulation of the sand movement inside the SCB, described in a paper just published in EPJ E. Their country is particularly affected by desertification, which affects 18% of its territory. The results will help us to understand sand fixation mechanisms that are relevant for sandstorm and land-desertification control.
- Published on 02 September 2013
The 2013 edition of the EPJE Pierre Gilles De Gennes prize has been awarded by the EPJE editors to Professor Julia Yeomans of the University of Oxford, UK. This initiative of the European Physical Journal E - Soft Matter and Biological Physics takes the name from the illustrious Nobel laureate who founded the journal.
Professor Yeomans has been nominated for her profound contribution to the study of the dynamical behaviour of complex and active liquids in confined geometries. She is an expert in theoretical and computational physics, particularly statistical physics, hydrodynamics, soft condensed matter and biological physics. Among her current research interests are microswimmers, active systems, liquid crystals and the interactions of fluids with structured surfaces.
- Published on 30 July 2013
Drug designers now have a new way of designing drug candidates suitable for dislodging unstable water molecules located in the defects at the surface of target proteins
New research shows a physical characterisation of the interface of the body’s proteins with water. Identifying the locations where is it easiest to remove water from the interface of target proteins could constitute a novel drug design strategy. The candidate drugs would need to be engineered to bind at the site of the protein where interfacial water is most easily dislodged. These findings, based on the work of María Belén Sierra from the National University of the South, in Bahia Blanca, Argentina and colleagues, recently published in EPJ E.
- Published on 30 July 2013
Study uncovers the effects of size variation in nanoscale blocks used in polymer mixes on their underlying architecture and inherent characteristics
Building structures by mixing lego bricks of two different sizes is child’s play. However, studying polymers endowed with an alternating nanostructure made of heterogeneous blocks is anything but straightforward. Theoretical physicist Mark Matsen, based at the University of Reading, UK, studies polymer mixes consisting of two-fold (AB) and three-fold (BAB) combinations of two types of nanoscale blocks. He has shown, in a study published in EPJ E, that the underlying heterogeneity of the blocks can cause polymers to switch to different nanoscale patterns and therefore display different properties. Numerous applications based on etching patterns on substrates, such as electronics, computer chips, and membranes endowed with a specific function, can benefit from such research.
- Published on 23 July 2013
Sheets of biological cells move along the organs they cover by altering the external concentrations of specific molecules, thanks to an absorption mechanism on the cells’ surface
What do wound healing, cancer metastasis, and bacteria colonies have in common? They all involve the collective displacement of biological cells. New research sheds some new light on the physical mechanisms provoking the displacement of a sheet of cell, known as an epithelium. It typically covers our organs including the stomach and intestine, as well as our epidermis. In a paper which appeared in EPJ E, Martine Ben Amar from Pierre and Marie Curie University in Paris explains the importance of understanding the displacement of the epithelium as a means of influencing the biological process involved in healing. And, ultimately, of helping to minimise scars.
- Published on 25 June 2013
Thin films of liquids and polymers are interesting systems for those seeking to test glass transition theories and their prediction of a characteristic transition length scale of a few nanometers. The anomalous phenomena observed in some of these nano-confined films has greatly advanced our understanding of theoretical and experimental soft matter physics.
These films are treated as equilibrium systems where surfaces and interfaces introduce monotonous long-range mobility gradients. Considering finite size and interfacial effects provides an intuitive but oversimplifies picture that falls short of explaining many phenomena, such as enhancement of segmental mobility near an absorbing surface or long-lasting metastable states in the liquid.
- Published on 12 June 2013
Stress generated by nano-motors within animal cells can lead to the creation of a condensed layer of filaments beneath the outer cell membrane
The mechanism responsible for generating part of the skeletal support for the membrane in animal cells is not yet clearly understood. Now, Jean-François Joanny from the Physico Chemistry Curie Unit at the Curie Institute in Paris and colleagues have found that a well-defined layer beneath the cell outer membrane forms beyond a certain critical level of stress generated by motor proteins within the cellular system. These findings, which offer a new understanding of the formation of this so-called cortical layer, have just been published in EPJ E.
- Published on 01 May 2013
A new study explores the counter-intuitive behaviour of a microgel composed of soft polymer blobs
Being a physicist offers many perks. For one, it allows an understanding of the substances ubiquitous in everyday industrial products such as emulsions, gels, granular pastes or foams. These are known for their intermediate behaviour between fluid and solid. Paint, for example, can be picked up on a paintbrush without flowing and spread under the stress of the brush stroke like a fluid. Baudouin Geraud and colleagues from the Light Matter Institute at the University of Lyon, France, have studied the flow of a microgel confined in microchannels. They have shown, in a study just published in EPJ E, that its behaviour under confinement differs from predictions based on standard theories. Indeed, its molecules are not only subjected to local forces, but also to neighbouring forces that affect its flow.