- Published on 14 June 2018
New model examines the relative role of random interactions between individuals in a crowd compared to interactions stemming from their eagerness to be on their way
Ever found yourself crushed in a metro station at rush hour? The mathematician Carlo Bianca and physicist Caterina Mogno, both from the engineering research lab ECAM-EPMI in Cergy-Pontoise, France, have developed a new model to study the movement of crowds exiting a metro station. In a recent study published in EPJ Plus, they have for the first time employed models typically used to study gases consisting of a large number of molecules that collide at random (known as thermostatted kinetic theory) to study the consequences of the different interactions occurring among pedestrians in a crowd while exiting a metro station.
- Published on 07 March 2018
The “Focus Point on the Transition to Sustainable Energy Systems” in the European Physical Journal Plus (EPJ Plus) tries to answer central questions regarding the planned Energy Transition, focusing on the power sector in Europe. Important is the role played by intermittent renewables as a low carbon electricity source, central in the plans by the EU Commission in its Energy Roadmap 2050. Their intermittency however strongly reduces efficiency and security of supply and back up by other systems is unavoidable – large storage and/or nuclear and/or fossil based. Storage of excess electricity production by intermittent renewables at the level required seems far-fetched at this moment and much more research will be needed before this can substantially contribute. With a limited contribution of dispatchable renewable electricity (hydro, bio-fuels etc.) and excluding à priori nuclear power, on various grounds, a continued use of fossil fuels imposes itself to guarantee a secured supply of electricity – in strong contrast with the original aims of the EU Energy Roadmap 2050. A rational debate involving all options is urgently needed and it is hoped that the set of papers in this focus point can contribute to improve insights in a determining factor for the future of our children and grandchildren.
EPJ Plus Highlight - Laser-ranged satellite measurement now accurately reflects Earth's tidal perturbations
- Published on 14 February 2018
The most precise ever laser satellite measurement method provides new clues to relativity
Tides on Earth have a far-reaching influence, including disturbing satellites’ measurements by affecting their motion. This disturbance can be studied using a model for the gravitational potential of the Earth, taking into account the fact that Earth’s shape is not spherical. The LAser RElativity Satellite (LARES), is the best ever relevant test particle to move in the Earth’s gravitational field. In a new study published in EPJ Plus, LARES proves its efficiency for high-precision probing of General Relativity and fundamental physics. By studying the Earth’s tidal perturbations acting on the LARES, Vahe Gurzadyan from the Center for Cosmology and Astrophysics at Yerevan State University, Armenia, and colleagues demonstrate the value of laser-range satellites for high-precision measurements.
- Published on 13 February 2018
The papers published in this Focus Point evidence the broad range of interests pursued by the Italian community active in the field of Planetary Sciences.
Although this selection of papers can by no means be considered to exhaustively represent the fields of interest of the community, many points of interests and activities are included, from PI activitities in Planetary Space Missions, both from ESA and NASA programmes (such as Bepi Colombo and Juno) to the study of physical and dynamical properties of minor bodies to the geological study of planetary surfaces to the study of atmospheres to cosmogeophysical studies of meteorites.
The Italian Research Institutes, Observatories and Universities hosting research groups active in Planetary Sciences are based in different regional locations on the Italian territory as also shown by the selection of articles published in this Focus Point, and are evidence of a growing interest of the Astrophysical Community in Planetary Sciences and of a rapid growth in the number of topics investigated and in the number of scientists involved.
- Published on 21 December 2017
New study shows that two seemingly diverging theories of ever-increasing disorder, known as entropy, can be tested against each other experimentally in the smallest possible systems
Have you ever tried turning the spoon back after stirring jam into a rice pudding? It never brings the jam back into the spoon. This ever-increasing disorder is linked to a notion called entropy. Entropy is of interest to physicists studying the evolution of systems made up of multiple identical elements, like gas. Yet, how the states in such systems should be counted is a bone of contention. The traditional view developed by one of the fathers of statistical mechanics, Ludwig Boltzmann - who worked on a very large number of elements - is opposed to the seemingly disjointed theoretical perspective of another founding scientists of the discipline, Willard Gibbs, who describes systems with a very small number of elements. In a new study published in EPJ Plus, Loris Ferrari from the University of Bologna, Italy, demystifies this clash between theories by analysing the practical consequences of Gibbs’ definition in two systems of a well-defined size. Ferrari speculates about the possibility that, for certain quantities, the differences resulting from Boltzmann's and Gibbs' approach can be measured experimentally.
- Published on 10 November 2017
SA new study uses a combination of glacial morphology and remote sensing measurement to explore the role of ice in shaping Martian landslides
How good is your Martian geography? Does Valles Marineris ring a bell? This area is known for having landslides that are among the largest and longest in the entire solar system. They make the perfect object of study due to their steep collapse close to the scarp, extreme thinning, and long front runout. In a new research paper published in EPJ Plus, Fabio De Blasio and colleagues from Milano-Bicocca University, Italy, explain the extent to which ice may have been an important medium of lubrication for landslides on Mars. This can in turn help us understand the geomorphological history of the planet and the environment of deposition.
- Published on 11 October 2017
Study reviews the state-of-the-art in polarimetry as a remote sensing technique for the small bodies in our solar system
The solar system is full of various small bodies such as planetary moons, main belt asteroids, Jupiter Trojans, Centaurs, trans-Neptunian objects and comets. To study them, scientists typically analyse the radiation they reflect, which is referred to as polarimetry. Scientists not only focus on the intensity of the scattered radiation, but also on how photons oscillate in the plane perpendicular to their direction of propagation - that is, their polarisation. Combining these two aspects yields significantly better descriptions than data obtained from the intensity alone. In a paper published in EPJ Plus, Stefano Bagnulo from Armagh Observatory and Planetarium in Northern Ireland, UK, and colleagues review the state-of-the-art in polarimetry for studying the small bodies in our solar system.
EPJ Plus Highlight - Best tactical approach to handling patients with simultaneous parasitic and HIV infection
- Published on 06 September 2017
New mathematical model for cryptosporidiosis - HIV co-infection explores their synergistic relationship in connection with prevention and treatment
One of the most common waterborne diseases worldwide is cryptosporidiosis, a parasitic disease affecting the small intestine and possibly our airways. It is a common cause of diarrhoea in HIV-positive patients, who are known to have lower immunity. Now Kazeem Oare Okosun from Vaal University of Technology in South Africa and colleagues from Pakistan and Nigeria have developed a new model and numerical simulations to determine the optimal combination of prevention and treatment strategies for controlling both diseases in patients who have been co-infected. Their results, recently published in EPJ Plus, show a positive impact on the treatment and prevention for cryptosporidiosis alone, for HIV-AIDS alone, or for both together.
- Published on 08 August 2017
During the past decades, new nuclear systems have been designed with the goals of ensuring the sustainability of nuclear energy, minimizing long-lived radioactive waste and improving the safety of nuclear reactors. This has led to the request for new or more precise nuclear data, either because reactions on isotopes neglected before have become important, or because new types of reactions have to be described. Nuclear data are in fact all the quantities necessary to describe the nuclear reactions occurring in a system.
In Europe, an important effort has been devoted to the collection of high quality nuclear data, and partially supported by the EURATOM framework programs: in particular ANDES (Accurate Nuclear Data for nuclear Energy Sustainability) and CHANDA (solving CHAllenges in Nuclear Data) in FP7. This EPJ Plus Focus Point issue presents part of the work performed during these programs.
All articles are freely accessible until 30 September 2017. For further information read the Editorial
- Published on 24 July 2017
Italian Space Agency presents plans to develop a robotic solar-powered spacecraft capable of displacing a near-Earth asteroid towards lunar orbit for ease of study
Future space exploration aims to fly further from Earth than ever before. Now, Italian Space Agency scientists have expressed an interest in contributing to the development of robotic technologies to bring an asteroid from beyond lunar orbit back into closer reach in order to better study it. In a paper published in EPJ Plus, Marco Tantardini and Enrico Flamini from the Italian Space Agency (ASI) make the case for taking part in the robotic phase of the Asteroid Redirect Mission (ARM). In addition to taking manned spaceflights deeper into space than ever before, the proposed mission would also bring some benefit for planetary science.