2022 Impact factor 3.4

EPJ Plus Highlight - Describing growing tissues in the language of thermodynamics

Cellular arrangements surrounding a tumour

New analysis shows how key properties of biological tissues can be accurately described in the mathematical language of Onsager’s variational principle, widely used to describe continually changing systems in thermodynamics.

A key feature of biological tissues is their inhomogeneity and their ability to grow via cell reproduction. To study this behaviour, it is important to describe it using equations, which account for factors including growth rates, chemical signalling, and tissue structure.

In doing this, researchers aim to develop consistent continuous descriptions of these deeply complex systems: accurately predicting properties such as cell reproduction rates, disorder, and how their growth varies in different space directions, depending on their interactions.

Through new analysis published in EPJ Plus, Joseph Ackermann and Martine Ben Amar at Sorbonne University Paris, show that tissue development can be reliably captured within ‘Onsager’s variational principle’: a mathematical framework used widely in thermodynamics.


Focus Point on Physics in the Balkans: Perspectives and Challenges

Guest editors: Luc Bergé, Goran S. Djordjević and Zoran V. Popović

One specificity of physics in the Balkans is the existence of a tradition, more than 30 years long, of organizing triennial Balkan congresses (International General Physics Conferences) within the Balkan Union of Physicists (BPU) as a platform for the presentation of the research results of hundreds of participants and their collaborators with the Balkans, from Europe and the world.

The aim of this Focus point of EPJ Plus is to contribute to an overview of the state of the art of research in physics in the Balkans. Eleven of the seventeen plenary and invited lecturers at the BPU11 Congress contributed to this issue. The Focus Point provides valuable insights and highlights results in already established areas, as well as some interesting new research avenues to pursue. This issue contains mainly original scientific papers with review elements in the fields of Solid State Physics, Physics of Materials, Econophysics, Quantum Optics and Laser Physics, Open Quantum Systems, Cosmic Rays and Hubble Tension in Cosmology, Nuclear and Collider Physics.

All articles are available here and are freely accessible until 31 May 2024. For further information, read the Editorial.

EPJ Plus Highlight - Beam balance designs could elucidate the origins of dark energy

The beam balance prototype

With some improvements, the instrument could help physicists to identify the mysterious origins of dark energy.

One of the greatest problems in modern physics is to reconcile the enormous difference between the energy carried by random fluctuations in the vacuum of space, and the dark energy driving the universe’s expansion.

Through new research published in EPJ Plus, researchers led by Enrico Calloni at the University of Naples Federico II, Italy, have unveiled a prototype for an ultra-precise beam balance instrument, which they hope could be used to measure the interaction between these vacuum fluctuations and gravitational fields. With some further improvements, the instrument could eventually enable researchers to shed new light on the enigmatic origins of dark energy.


EPJ Plus Highlight - Unlocking the full potential of Auger electron spectroscopy

Different regimes of core-hole creation and recombination

A new computational approach makes more realistic assumptions about the redistribution of energy during the Auger process, improving the accuracy of Auger electron spectroscopy.

Auger electron spectroscopy (AES) is an incredibly useful technique for probing material samples – but current assumptions about the process ignore some of the key time-dependent effects it involves. So far, this has resulted in overly-simplified calculations, which have ultimately prevented the technique from reaching its full potential.

Through a new study published in EPJ Plus, Alberto Noccera at the University of British Columbia, Canada, together with Adrian Feiguin at Northeastern University, United States, developed a new computational approach which offers a more precise theoretical description of the AES process, while taking its time dependence into account. Their method could help researchers to improve their quality of material analysis across a wide array of fields: including chemistry, environmental science, and microelectronics.


EPJ Plus Highlight - Better calculations for the magnetic properties of neodymium compounds

Measuring spin-orbit transitions

Valuable magnetic properties of neodymium compounds have so far remained difficult to probe using high-energy neutron spectroscopy. A new correction to the technique could make these measurements far more feasible.

High-energy neutron scattering is a powerful tool in spectroscopy, allowing researchers to probe the physical and chemical properties of many different materials. It is especially well suited for studying the dense and complex structures of lanthanide-iron intermetallic compounds, such as the celebrated Nd2Fe14B. So far, however, researchers still haven’t figured out how to probe the material’s valuable magnetic properties using neutron scattering. In a new study published in EPJ Plus, Michael Kuz’min at Aix-Marseille University, together with Manuel Richter at Leibniz IFW Dresden, present a correction to the technique which could be used to determine the ‘exchange field’ of Nd: an important indicator of its magnetic properties.


EPJ Plus Highlight – Magnetic Shielding for Particle Detectors

Elliptical coils counter geomagnetic field interference at a detector’s base. Credit: Cabo et al. 2023

Carefully positioned wire coils can improve photodetector efficiency by counteracting Earth’s magnetic field

Particle physicists who hunt for neutrinos, cosmic-rays, and other charged particles rely on sophisticated instruments that detect very faint bursts of light given off when incident particles interact with a medium. The most common such instruments, called Cherenkov detectors, use photomultiplier tubes to capture as much of this light as possible. This provides a meaningful signal from which to glean information about the particle from whence it came. But their efficiency drops when subjected to Earth’s magnetic field.

In a study published in EPJ Plus, Sara Rodriguez Cabo, of the University of Oviedo, Spain, and her colleagues, now describe how specific arrangements of current-carrying wire coils around large cylindrical detectors can compensate for natural magnetic disturbances and shield photodetectors from it.


EPJ Plus Highlight - Beyond the Periodic Table: Superheavy Elements and Ultradense Asteroids

Graph showing the densities of all elements from Z=1 to 100, with the heavy metals labelled with red triangles. The red triangle at the top right is osmium (Z=76), the element with the highest experimentally measured mass density.

Predictions of the behaviour of super-heavy elements that have not yet been observed on Earth may help explain the properties of dense asteroids further motivating potential asteroid miners.

Some asteroids have measured densities higher than those of any elements known to exist on Earth. This suggests that they are at least partly composed of unknown types of ‘ultradense’ matter that cannot be studied by conventional physics. Jan Rafelski and his team at the Department of Physics, The University of Arizona, Tucson, USA, suggest that this could consist of superheavy elements with atomic number (Z) higher than the limit of the current Periodic Table. They modelled the properties of such elements using the Thomas-Fermi model of atomic structure, concentrating particularly on a proposed ‘island of nuclear stability’ at and around Z=164 and extending their method further to include more exotic types of ultra-dense material. This work has now been published in EPJ Plus.


EPJ Plus Focus Point Issue: Progress in Medical Physics in Times of CoViD-19 and Related Inflammatory Diseases

Guest editors: E. Cisbani, S. Majewski, A. Gori, F. Garibaldi

COVID-19 is a systemic disease attacking the total body; one of the signatures of the disease is inflammation, an extremely complex phenomenon, in different parts of the body, that can benefit of a multidisciplinary imaging approach. Understanding inflammation is an important step for curing from COVID-19; its role must be understood, in particular for the strategies and technologies to be used against COVID-19, its consequences and potential future pandemics. Among the molecular imaging technologies that can play a central role is the Nuclear Medicine imaging. New advanced technologies that are under development could translate into increased sensitivity of early detection, avoiding the long-term side effects of inflammation. In this context, the Focus Point presents the most promising developments for more effective imaging in Nuclear Medicine. The intrinsic multidisciplinary and the related difficulty to address complex, specific, questions to the different scientific communities have been taken into account in the selection of the contributions, their scientifically sounding relevance and at the same time their capability to be understandable outside their reference discipline.


EPJ Plus Highlight - Introducing the European strategy for accelerator-based photon science (ESAPS 2022)

Timeline of future upgrades

Through new plans detailed in ESAPS 2022, the LEAPS consortium aims to strengthen Europe as a global leader in accelerator-based photon science.

The League of European Accelerator-based Photon Sources (LEAPS) is made up of 19 large-scale synchrotron (SR) and Free-electron Laser (FEL) facilities, situated across 10 European countries. This contribution to the EPJ Plus Focus Point “Accelerator-based Photon Science Strategy, Prospects and Roadmap in Europe: a Forward View to 2030” introduces the European Strategy for Accelerator-based Photon Science (ESAPS 2022): a pan-European plan formulated by LEAPS aimed at addressing the future challenges and needs in science and innovation, which strengthens Europe as a global leader in many areas of research and technology. Through the plans set out in ESAPS 2022, LEAPS could soon provide valuable new resources for more than 35,000 researchers using its facilities today, spanning fields as wide-ranging as materials science, drug design, biochemistry, quantum technology, geology, and planetary science.


EPJ Plus Focus Point Issue: Focus Point on Environmental and Multiplicity Effects on Planet Formation

Guest Editors: Giuseppe Lodato and Carlo Felice Manara

Star formation does not take place in isolation, and young stars are subject to different kind of interactions with their natal environment. Dynamical encounters with other young stars and photoevaporation of the protostellar disc due to the intense UV field of neighbouring stars are just a couple of examples of how the environment affects star formation. Since planets are born during the star formation process, such effects may naturally affect also planet formation itself. The aim of this focus point is to define the state of the art of our knowledge in this particular field and to provide a few highlights of interesting new research avenues to pursue.

All articles are available here and are freely accessible until 24 October 2023. For further information, read the Editorial.

B. Fraboni and G. García López
The typing and the arrangement of tables and figures are perfect. Also, corrections to English and bibliography were appropriate. All together there is no correction to be made and I thank you for the excellent work. I would also thank you for the kind promptness in delivering the proofs.

Maurizio Consoli, Istituto Nazionale di Fisica Nucleare - Sezione di Catania, Italy

ISSN: 2190-5444 (Electronic Edition)

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