- Published on 07 May 2021
The use of light to move matter has a wide range of technological applications and could one day even power spaceflight. New research suggests a method to better understand this subtle phenomenon.
We are all familiar with the sight of a white pool ball striking a red and smoothly transferring its momentum. What is less familiar is that light can also transfer momentum and is even able to give objects a tiny push. A new paper published in EPJ Plus suggests a way to examine the mechanism behind light’s subtle momentum transfer — the Poynting vector. The paper is the work of Manuel Marqués of IFIMAC-The Condensed Matter Physics Center, and the Nicolás Cabrera Institute (INC), Universidad Autónoma de Madrid, Spain, and Shulamit Edelstein and Pedro Serena from the Spanish National Research Council (CSIC).
- Published on 06 May 2021
The way cells adhere to surfaces is an important element in allowing them to form cohesive tissues. A new study looks at how cells stick to a surface and spread across it.
Observing how cells stick to surfaces and their motility is vitally important in the study of tissue maintenance, wound healing and even understanding how cancers progress. A new paper published in EPJ Plus, by Raj Kumar Sadhu, Weizmann Institute of Science, Rehovot, Israel, takes a step towards a deeper understanding of these processes.
- Published on 19 March 2021
This Focus Point covers twelve original papers obtained from advanced theoretical analysis, experimental, and numerical simulations in Cancer and HIV/AIDS research. Results include a randomized discrete logistic equation to describe the dynamics of breast tumor; a mathematical model of breast cancer involving a system of differential equations with piecewise constant arguments to analyze the tumor growth and chemotherapeutic treatment; a new stochastic HIV mathematical model; incorporation of the Beddington–DeAngelis incidence rate to a continuous-time HIV infection model with cure rate and full logistic proliferation; a model for the tumor and normal cell growth under the influence of carcinogenic agents, an immunomodulator and variable influx of immune cells; a within-host HIV dynamical model under the effect of cytotoxic T lymphocytes immune response; the study of the interaction between drug addiction and the contagion of HIV/AIDS; a system of fractional differential equations with delays and a new computational method based on hybrid functions and Legendre polynomials with application to immunodeficiency viruses systems; investigation of cervical cancer; an HIV/AIDS epidemic model under fractal-fractional-order derivatives; study of the dynamics of HIV-AIDS infection via a fractional order SICA system; and sufficient conditions for the stability of a system describing the growth of malignant tumors.
- Published on 29 January 2021
Building on previous studies of muon tomography techniques, this topical issue demonstrates a full-scale prototype for the technology, capable of determining the position of a small lead block within a large sensing area
Each year, billions of tons of goods are transported globally using cargo containers. Currently, there are concerns that this immense volume of traffic could be exploited to transport illicit nuclear materials, with little chance of detection. One promising approach to combating this issue is to measure how goods interact with charged particles named muons – which form naturally as cosmic rays interact with Earth’s atmosphere. Studies worldwide have now explored how this technique, named ‘muon tomography,’ can be achieved through a variety of detection technologies and reconstruction algorithms. In this article of EPJ Plus, a team headed by Francesco Riggi at the University of Catania, Italy, build on these results to develop a full-scale muon tomograph prototype.
- Published on 15 January 2021
Nonlinear waves have long been at the research focus of both physicists and mathematicians, in diverse settings ranging from electromagnetic waves in nonlinear optics to matter waves in Bose-Einstein condensates, from Langmuir waves in plasma to internal and rogue waves in hydrodynamics. The study of physical phenomena by means of mathematical models often leads to nonlinear evolution equations known as integrable systems. One of the distinguished features of integrable systems is that they admit soliton solutions, i.e., stable, localized traveling waves which preserve their shape and velocity in the interaction. Other fundamental properties are their universal nature, and the fact that they can be effectively linearized, e.g., via the inverse scattering transform, or reduced to appropriate Riemann-Hilbert problems. Moreover, solutions can often be derived by the Zakharov-Shabat dressing method, by Backlund or Darboux transformations, or by Hirota’s method. Prototypical examples of such integrable equations in 1+1 dimensions are the nonlinear Schrödinger equation and its multicomponent generalizations, the sine-Gordon equation, the Korteweg-de Vries and the modified KdV equations, etc. In 2+1 dimensions the most notable examples are the Kadomtsev-Petviashvili (KP) equations, and the Davey-Stewartson equations. The aim of this special issue is to present the latest developments in the theory of nonlinear waves and integrable systems, and their various applications.
- Published on 10 September 2020
New understanding of the electrical properties of graphene nanoribbons (GRBs), when bounded with aromatic molecules, could have significant benefits in the development of chemosensors and personalised medicine.
Graphene is a modern wonder material possessing unique properties of strength, flexibility and conductivity whilst being abundant and remarkably cheap to produce, lending it to a multitude of useful applications – especially true when these 2D atom-thick sheets of carbon are split into narrow strips known as Graphene Nanoribbons (GNRs). New research published in EPJ Plus, authored by Kristiāns Čerņevičs, Michele Pizzochero, and Oleg V. Yazyev, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland, aims to better understand the electron transport properties of GNRs and how they are affected by bonding with aromatics. This is a key step in designing technology such chemosensors.
- Published on 24 July 2020
The Special Issue contains the articles which were presented at the International research and practice conference “Nanotechnology and Nanomaterials” (NANO-2018), which was organized by the Institute of Physics of NAS of Ukraine with the participation of the Yuriy Fedkovych Chernivtsi National University (Ukraine), University of Tartu (Estonia), University of Turin (Italy), Pierre and Marie Curie University – Paris 6 (France).
The Special Issue gathered high-level articles at the forefront of nanoscience research which is devoted to: the optical absorption by a nanosystem with dielectric quantum dots; the fabrication of crystalline Bi2TeO5 - Bi4Si3O12 - SiO2 nanocomposite; the existence of both size and “even-odd” effects for the lifetime of carbyne-based nanodevices consisting of two graphene sheets connected by a carbyne chain; the adsorption properties of the silica-titanium mixed oxide; the adsorption properties and application perspectives of BSA films as sensitive coatings for gas sensors; the properties of MgFe2O4; to the problem of band broadening of SPR; the structural studies concerning the formation of self-assembled indium deposited nanostructures on the (100) surface of In4Se3 layered semiconductor and the possibility of constructing the general dynamic properties of a conduction electron injected into graphene in the rectangular lattice approximation.
The Guest Editor, Olena Fesenko, hopes that this collection provides a quick overview on recent trends in this emerging field of research.
- Published on 23 April 2020
With the right approach, statistics can be used to reliably track the growth and fall in daily new cases of Covid-19 in China, raising hopes that similar approaches could more accurately predict the spread of the virus in other nations.
Efforts to contain the spread of the Covid-19 pandemic are now the top priority of governments across the globe. As they make these life-saving decisions, it is particularly crucial for policymakers to accurately predict how the spread of the virus will change over time. Through research published in EPJ Plus, Ignazio Ciufolini at the University of Salento, and Antonio Paolozzi at Sapienza University of Rome, identify a clear mathematical trend in the evolution of daily new cases and death numbers in China, and use the same curve to predict how a similar slowdown will unfold in Italy.
- Published on 01 April 2020
By treating meat as a network of flexible polymers surrounded by flowing moisture, computer models can accurately predict how much it will shrink when cooked.
Meat is no ordinary solid. Made up of complex networks of moisture-saturated proteins, it displays some intriguing physical properties when it is cooked. Several studies in the past have attempted to recreate this behaviour in computer simulations, but because this demands so much computing power, they have only achieved simplified, one-dimensional recreations of the process, which aren’t particularly accurate. In new research published in EPJ Plus, mathematicians led by Dr Hala Nelson at James Madison University show that by modelling meat as a fluid-saturated matrix of elastic proteins, which are deformed as the fluid moves, cooking behaviours can be simulated more precisely.
- Published on 17 January 2020
This special issue is related to the 3rd edition of the International Conference on Innovation in Art Research and Technology (inArt 2018) held in Parma (Italy). The Focus Point includes 20 excellent examples of the research works presented at the Conference. In particular, attention is focused on: non-invasive investigation techniques; new materials for restoration in compliance with the artifacts and the environment; products for the prevention of corrosion and of degradation; self-cleaning materials. The articles are devoted to the study of many different art objects and materials, including paintings (pigments, dyes, binders), textiles, manuscripts, buildings as well as building materials, metals, glasses, gems, bones and ivory. The analyzed objects span a huge time interval, ranging from antiquity (ancient Egypt) to contemporary art. Many different techniques are involved: spectroscopy in the different ranges of the electromagnetic spectrum (from infrared to X-rays); visible and electron microscopy; multispectral imaging; three-dimensional reconstruction, using instruments as handheld spectrometers, neutron sources or particle accelerators. Data treatment is also discussed, from databases to data integration and decision tools.