News / Highlights / Colloquium
- Published on 07 June 2014
Separating particles from the liquid they are in can now be done with a new concept, based on horizontal deflection during particle levitation for the separation of minerals and particles.
Magnetic separators exploit the difference in magnetic properties between minerals, for example when separating magnetite from quartz. But this exercise becomes considerably more complex when the particles are not magnetic. In the wake of previous particle levitation experiments under high-power magnetic fields, a new study reveals that particles are deflected away from the magnet’s round-shaped bore centre in a horizontal direction. Previous studies had observed the vertical levitation of the particles. These findings are presented by Shixiao Liu from the Faculty of Engineering, University of Nottingham, UK and colleagues, in a paper recently published in EPJ E, and could led to a new concept in particles and minerals separation technologies.
- Published on 28 May 2014
A new study investigates the role of cells’ alignment in shaping biological tissue, as cell division provides dynamic evolution during tissue growth.
A team of European scientists has now extended a previous biophysical model to investigate elongated growth within biological tissues to describing the evolution over time of the shape of a fruit fly’s wing. They found the aspect ratio of the typical biological shapes may exhibit a maximum at finite time and then decrease. For sufficiently large tissues, the shape is expected to approach that of a disk or sphere. These findings have been reported by Carles Blanch-Mercader from the University of Barcelona, Spain, and colleagues, in a paper published in EPJ E. They provide a more general classification than previously available of the different types of morphologies a tissue can be expected to attain, depending on its initial size and its physical properties.
- Published on 29 April 2014
A new model accounting for the loss of stability occurring at the very start of supernova explosions sheds some new light on this phenomenon, opening up potential broader applications
Exploding supernovae are a phenomenon that is still not fully understood. The trouble is that the state of nuclear matter in stars cannot be reproduced on Earth. In a recent paper published in EPJ E, Yves Pomeau from the University of Arizona, USA, and his French colleagues from the CNRS provide a new model of supernovae represented as dynamical systems subject to a loss of stability, just before they explode. Because similar stability losses also occur in dynamical systems in nature, this model could be used to predict natural catastrophes before they happen. Previous studies of the creeping of soft solids, earthquakes, and sleep-wake transitions have already confirmed the validity of this approach.
- Published on 07 April 2014
This month EPJE welcomes Andreas Bausch, who takes over from Frank Jülicher, as Editor in Chief for biological physics in EPJ E – Soft Matter and Biological Physics. In his lab, Bausch applies new experimental tools of soft condensed matter physics to living cells and bio-mimetic model systems. This is his vision for biological physics within EPJE in the years to come:
- Published on 26 March 2014
A better understanding of the physical response of combination materials made of nanotubes with ferroelectric liquid crystals could soon open the door to applications as sensors or switches
Dispersions of carbon nanotubes with liquid crystals have attracted much interest because they pave the way for creating new materials with added functionalities. Now, a study published in EPJ E by Marina Yakemseva and colleagues at the Nanomaterials Research Institute in Ivanovo, Russia, focuses on the influence of temperature and nanotube concentration on the physical properties of such combined materials. These findings could have implications for optimising these combinations for non-display applications, such as sensors or externally stimulated switches, and novel materials that are responsive to electric, magnetic, mechanical or even optical fields.
- Published on 24 March 2014
Foams and foaming processes pose interesting questions for both fundamental research and practical applications. Although foams are a familiar thing, both in our everyday lives and in industry, many aspects of foam physics and chemistry still remain unclear.
This EPJ E paper comprehensively reviews the studies of foams under microgravity, including studies conducted in parabolic flights, in sounding rockets and in the International Space Station.
- Published on 24 January 2014
The inner structure of soft adhesive materials during the debonding process is, for the first time, under scrutiny in the hope of producing new, improved adhesives in the future
Tape, self-adhesive labels, Post-it notes and masking tape all contain soft adhesives. This makes them easy to remove—a process referred to as debonding. French scientists have studied how soft adhesives work in the hope of facilitating the design of more efficient adhesives. Francois Tanguy, a researcher at ESPCI ParisTech, the School of Industrial Physics and Chemistry, in Paris, France, and colleagues have, for the first time, performed a precise analysis of the material deformation and structure during the course of debonding for several model adhesives. Their findings are published in EPJ E. By better understanding the connection between the energy dissipated by the polymeric material with adhesive qualities and its response to traction, they hope to improve models of adhesive performance.
- Published on 18 December 2013
A new study focuses on the motion of motor proteins in living cells, applying a physicist’s tool called non-equilibrium statistical mechanics
Motion fascinates physicists. It becomes even more intriguing when observed in vivo in biological cells. Using an ingenious setup, Japanese scientists have now calculated the force of molecular motors acting on inner components of biological cells, known as organelles. In this study, the focus is on mitochondria—akin to micrometric range cellular power plants—travelling along microtubules in a cell. Published in EPJ E by Kumiko Hayashi, from Tohoku University, Sendai, Japan, these findings could contribute to elucidating the transport mechanism in biological cells by multiple motors.
- Published on 11 December 2013
A new Colloquium in EPJE by Xiao-Jing Zheng introduces and reviews the fundamental laws of the electrification of wind-blown sand and their influence, and highlights the challenges in this field.
The electrification of wind-blown sand is a typical complex system characterised by nonlinearity, randomness, multi-field coupling between thermal diffusion, E-fields and sand movements, as well as trans-scale processes with multi-phase media. Owing to the complex mechanism and the influence of the electrification of wind-blown sand , a number of issues remain poorly understood. These include: (1) why sand particles get charged during wind-blown sand movements; (2) how many electric charges a sand particle acquires; (3) why the electric polarity of sand particles is related to the particles’ size; (4) what the change law of wind-blown sand E-fields is, and (5) how to predict the intensity and influence of wind-blown sand E-fields.
- Published on 06 November 2013
No better solution to studying ever-draining foams than applying a strong magnetic field to keep the liquid in the foam at a standstill by levitating its water molecules
Foams fascinate, partly due to their short lifespan. Foams change as fluid drains out of their structure over time. It is precisely their ephemeral nature which has, until now, prevented scientists from experimentally probing their characteristic dynamics further. Instead, foams have often been studied theoretically. Now, Nathan Isert from the University of Konstanz, Germany and colleagues, have devised a method of keeping foams in shape using a magnet, which allows their dynamics to be investigated experimentally, as recently described in EPJ E.