EPJ Plus Highlight - New neuron dynamics model better fitted to the biological reality

The phase trajectories of the solutions for the simplified biologically relevant HH model and the scaled theoretical FHN model for neuron dynamics (black curve).

Scientists have now adopted a qualitative theoretical neuroscience model commensurate with actual measurements of neurons' dynamics

Neuroscientists are currently working diligently to understand the dynamics of thousands of coupled neurons. Understanding how they operate requires accurate models. The trouble is that each of the existing neuroscience models has its own shortcomings. Russian physicists have, for the first time, developed an effective method for solving the equations of a well-known theoretical neuroscience dynamic model and make it more biologically relevant. These findings have just been published in EPJ Plus by Eugene Postnikov and Olga Titkova from Kursk State University, Russia. They could not only help resolve problems in the neurosciences, but could also provide a deeper understanding of neuronal activity in the emerging sector of neurovascular dynamics, which describes the interplay between the brain's neurons and the blood flow.

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EPJ Plus Highlight - Pushing the boundaries of magnet design

Representation of the magnetic anisotropy of single ions contained in the rare-earth components of the magnets in the study.

New method to make permanent magnets more stable over time

For physicists, loss of magnetisation in permanent magnets can be a real concern. In response, the Japanese company Sumitomo created the strongest available magnet—one offering ten times more magnetic energy than previous versions—in 1983. These magnets are a combination of materials including rare-earth metal and so-called transition metals, and are accordingly referred to as RE-TM-B magnets. A Russian team has now been pushing the boundaries of magnet design, as published in a recent study in EPJ Plus. They have developed methods to counter the spontaneous loss of magnetisation, based on their understanding of the underlying physical phenomenon. Roman Morgunov from the Institute of Problems of Chemical Physics at the Russian Academy of Sciences and colleagues have now developed a simple additive-based method for ensuring the stability of permanent magnets over time, with no loss to their main magnetic characteristics.

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EPJ Plus Highlight - Improving safety of neutron sources

Sampling of Lead-Bismuth-eutectic material/cover gas-interface sample consisting of solid material forming a powdery crust onto the steel wall.

Testing liquid metals as target material bombarded by high-energy particles

There is a growing interest in the scientific community in a type of high-power neutron source that is created via a process referred to as spallation. This process involves accelerating high-energy protons towards a liquid metal target made of material with a heavy nucleus. The issue here is that scientists do not always understand the mechanism of residue nuclei production, which can only be identified using spectrometry methods to detect their radioactive emissions. In a new study examining the radionuclide content of Lead-Bismuth-eutectic (LBE) targets, scientists at the Paul Scherrer Institute Villigen (PSI) found that some of the radionuclides do not necessarily remain dissolved in the irradiated targets. Instead, they can be depleted in the bulk LBE material and accumulate on the target's internal surfaces. These findings have recently been published in EPJ Plus by Bernadette Hammer-Rotzler affiliated with the PSI and the University of Bern, Switzerland, and colleagues from Switzerland, France and Sweden. The results improve our understanding of nuclear data related to the radionuclides stemming from high-power targets in spallation neutron sources. They contribute to improving the risk assessment of future high-power spallation neutron beam facilities --including, among others, the risk of erroneous evaluation of radiation dose rates.

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EPJ Plus Highlight - Sweden’s 100% carbon-free emissions challenge

The figure shows the reduced load along with the original nuclear power, the contribution of which is halved. It also shows the increased contribution from wind necessary and that from a backup system.

Replacing nuclear power with wind power doesn't make sense in Sweden, study shows

The Swedish power supply is largely free of carbon emissions. Indeed, it is mainly based on a combination of hydroelectric and nuclear power combined with power exchange with neighbouring Scandinavian countries. A study published in EPJ Plus investigates the possibility of replacing nuclear power with wind power, which is by nature intermittent. According to the study, this, in turn, would finally lead to a reduction in the use of hydroelectricity if the annual consumption remained constant. The authors of the study conclude that a backup system, based on fossil fuel, namely gas, would be required in combination with wind power. In such a scenario, the CO2 emissions would double. Fritz Wagner from the Max Planck Institute for Plasmaphysics, Greifswald, Germany, and Elisabeth Rachlew from the Royal Institute of Technology, Stockholm, Sweden, therefore conclude that it would not be a viable option.

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EPJ Plus Highlight - You were right: rotational motion is relative, too, Mr Einstein!

Einstein's relativity theory also applies to rotational motion. © sakkmesterke / Fotolia

Extension of the relativity theory to rotational motion, one hundred years after Einstein first published the general theory of relativity

It has been one hundred years since the publication of Einstein’s general theory of relativity in May 1916. In a paper recently published in EPJ Plus, Norwegian physicist Øyvind Grøn from the Oslo and Akershus University College of Applied Sciences and his co-author Torkild Jemterud demonstrate that the rotational motion in the universe is also subject to the theory of relativity.

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EPJ Plus Highlight - Back to basics with thermoelectric power

Determination of the Seebeck coefficient for a circuit composed of two dissimilar materials.

New study highlights the role of electron diffusivity when turning waste heat into electricity

Many phenomena in physics, though well-known, are not necessarily widely understood. That’s the case with thermoelectricity, which harnesses waste heat by coupling heat flux and electric current. However, understanding such phenomena is important in order to leave the door open for discovering novel manifestations of them. Thus, even today physicists working in the area of thermoelectricity continue to ask fundamental questions about the underlying physical process. For example, in a recent study, a team based in France questioned the nature of the force that puts electrons to work when a temperature difference is applied across a thermoelectric material. Now, Henni Ouerdane, affiliated to the Russian Quantum Center near Moscow, and colleagues have published in EPJ Plus a study showing that the force that puts electrons to work to harness the waste heat is linked to the ability of electrons to diffuse through the material. Potential applications in the field of electrical power production from waste heat include thermoelectric devices designed to boost power over a range spanning ten orders of magnitude: typically from microwatts to several kilowatts.

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EPJ Plus Highlight - Scrutinising the tip of molecular probes

The solid lines indicate the temperature range used to estimate the amount of molecules loaded onto the probe.

Nature of interaction of probe molecules on the surface of oxide particles elucidated

Studies of molecules confined to nano- or micropores are of considerable interest to physicists. That’s because they can manipulate or stabilise molecules in unstable states or obtain new materials with special properties. In a new study published in EPJ Plus, Stefan Frunza from the National Institute of Materials Physics in Romania and colleagues have discovered the properties of the surface layer in probe molecules on the surface of oxide particles. These properties depend on the interaction at the interface. In this particular study, probes are formed by adsorption of rod-like cyanophenyl derivates on the surface of oxide particles. The authors found that their surface layers behave like glass-forming liquids.

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EPJ Plus - Paolo Biscari becomes Deputy Editor-in-Chief

Professor Paolo Biscari

EPJ Plus has the great pleasure to announce the appointment of Professor Paolo Biscari as deputy Editor-in-Chief of the journal.

Paolo Biscari is Full Professor in Condensed Matter Physics at the Department of Physics of the Politecnico di Milano. At Politecnico di Milano he is Dean of the PhD School, which coordinates the researches of approximately 900 PhD candidates. He is Deputy Editor-in-Chief of the European Physical Journal Plus, and member of the Editorial Board of the Springer Book Series "Unitext". His research is focused in the soft matter area, and more specifically in liquid crystals, elastomers, and critical phenomena. He has been Invited Professor at the Universities of Southampton and Minnesota, has published more than 60 research papers in international peer-reviewed journals, three books, and has contributed to approximately 50 international congresses as Invited Speaker. He has directed as PI several research grants and contracts, awarded from both public Institutions and private companies. In 2004, he earned the Bruno Finzi Prize, awarded by the Istituto Lombardo, Accademia di Scienze e Lettere, for his research in Applied Mechanics.

EPJ Plus Highlight - Physical parameters matter in terms of cancer cells’ metastatic ability

Plots of single-cell trajectories stimulated by different levels of epidermal growth factor.

Scientists develop potential visual test for diagnosing invasive states of breast cancer cells

The micro-environment surrounding cancer cells is just as important as genes in regulating tumour progression. Scientists have therefore examined the biophysical and biochemical cues occurring in the vicinity of cancer cells. This represents a departure from the traditional measurement of secreted molecules, called biomarkers. The latest research in this field, recently published in EPJ Plus, found that the presence of a substance called Epidermal Growth Factor (EGF) promotes the motility of elongated mesenchymal tumour cells, which migrate depending on their adhesive properties by climbing along collagen fibres, in contrast to rounded tumour cells, which migrate in an adhesion-independent manner. These findings stem from the work of Dongil Geum and BJ Kim in the Wu biofluifics lab at Cornell University, Ithaca, New York, USA.

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EPJ Plus Focus Point - 3He replacement in neutron detection: Current status and perspectives

One of the most important issues that the neutron community is currently facing is related to the lack of 3He for detection purposes. This problem has triggered an interesting and stimulating research and development activity worldwide, with the aim of finding effective and cheap solutions for 3He replacement. With the advent of new materials, advanced electronics and more powerful real time computing tools it has now become possible to investigate novel designs of neutron detectors to be used in various fields of research and technology, and to address the needs of more sophisticated applications.

The aim of this issue is to present an up-to-date, although not exhaustive, review on the R&D activities on 3He-free neutron detectors, with the aim of generating further discussions and activities on the subject, stimulate synergies between groups with different expertise, and show examples of existing neutron sources where new detectors and techniques can be tested and validated. This EPJ Plus Focus Point addresses all aspects related to the design of an innovative 3He-free neutron detector, from the development of new detection concepts and active material, to fast front-end electronics and acquisition systems, to the availability of neutron beams of suitable energy for detector characterization.

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