On a class of n-Leibniz deformations of the simple Filippov algebras

We study the problem of the infinitesimal deformations of all real, simple, finite-dimensional Filippov (or n-Lie) algebras, considered as a class of n-Leibniz algebras characterized by having an n-bracket skewsymmetric in its n-1 first arguments. We prove that all n>3 simple finite-dimensional Filippov algebras are rigid as n-Leibniz algebras of this class. This rigidity also holds for the Leibniz deformations of the semisimple n=2 Filippov (i.e., Lie) algebras. The n=3 simple FAs, however, admit a non-trivial one-parameter infinitesimal 3-Leibniz algebra deformation. We also show that the $n\geq 3$ simple Filippov algebras do not admit non-trivial central extensions as n-Leibniz algebras of the above class.Comment: 19 pages, 30 refs., no figures. Some text rearrangements for better clarity, misprints corrected. To appear in J. Math. Phy

On domain walls in a Ginzburg-Landau non-linear S^2-sigma model

The domain wall solutions of a Ginzburg-Landau non-linear $S^2$-sigma hybrid model are unveiled. There are three types of basic topological walls and two types of degenerate families of composite - one topological, the other non-topological- walls. The domain wall solutions are identified as the finite action trajectories (in infinite time) of a related mechanical system that is Hamilton-Jacobi separable in sphero-conical coordinates. The physical and mathematical features of these domain walls are thoroughly discussed.Comment: 26 pages, 18 figure

Blurred Lines Between Competition and Parasitism

Accurately describing the ecological relationships between species is more than mere semantics-doing so has profound practical and applied implications, not the least of which is that inaccurate descriptions can lead to fundamentally incorrect predicted outcomes of community composition and functioning. Accurate ecological classifications are particularly important in the context of global change, where species interactions can change rapidly following shifts in species composition. Here, we argue that many common ecological interactions-particularly competition and parasitism-can be easily confused and that we often lack empirical evidence for the full reciprocal interaction among species. To make our case and to propose a theoretical framework for addressing this problem, we use the interactions between lianas and trees, whose outcomes have myriad implications for the ecology and conservation of tropical forests (e.g., Schnitzer et al. 2015)

Virtual libraries of tissue and clinical samples: potential role of a 3-D microscope.

Our international innovative teaching group from different European Universities (De Montfort University, DMU, UK; and the Spanish University of Alcalá, University Miguel Hernández and University of San Pablo CEU), in conjunction with practicing biomedical scientists in the National Health Service (UK) and biomedical researchers, are developing two complete e-learning packages for teaching and learning medical parasitology, named DMU e-Parasitology (accessible at: http://parasitology.dmu.ac.uk), and biology and chemistry, named DMU e-Biology (accessible at: http://parasitology.dmu.ac.uk/ebiology/index.htm), respectively. Both packages will include a virtual microscope with a complete library of digitised tissue images, clinical slides and cell culture slides/mini-videos for enhancing the teaching and learning of a myriad of techniques applicable to health science undergraduate and postgraduate students. Thus, these packages include detecting human parasites, by becoming familiar with their infective structures and/or organs (e.g. eggs, cysts) and/or explore pathogenic tissues stained with traditional (e.g. haematoxylin & eosin) or more modern (e.g. immunohistochemistry) techniques. The Virtual Microscope (VM) module in the DMU e-Parasitology package is almost completed (accessible at: http://parasitology.dmu.ac.uk/learn/microscope.htm) and contains a section for the three major groups of human-pathogenic parasites (Peña-Fernández et al., 2018) [1]. Digitised slides are provided with the functionality of a microscope by using the gadget Zoomify®, and we consider that they can enhance learning, as previous studies reported in the literature have reported similar sensitivity and specificity rates for identification of parasites for both digitised and real slides. The DMU e-Biology’s VM, currently in development, will provide healthy and pathological tissue samples from a range of mammalian tissues and organs. This communication will provide a description of both virtual libraries and the process of developing them. In conjunction, we will use a three-dimensional (3D) super-resolution microscopy, 3D Cell Explorer (Nanolive, Lausanne, Switzerland), to incorporate potential 3D microscopic photographs/short videos of cells to provide students with information about the spatial arrangement and morphologies of cells that are essential for life

Scalar and tensorial topological matter coupled to (2+1)-dimensional gravity:A.Classical theory and global charges

We consider the coupling of scalar topological matter to (2+1)-dimensional gravity. The matter fields consist of a 0-form scalar field and a 2-form tensor field. We carry out a canonical analysis of the classical theory, investigating its sectors and solutions. We show that the model admits both BTZ-like black-hole solutions and homogeneous/inhomogeneous FRW cosmological solutions.We also investigate the global charges associated with the model and show that the algebra of charges is the extension of the Kac-Moody algebra for the field-rigid gauge charges, and the Virasoro algebrafor the diffeomorphism charges. Finally, we show that the model can be written as a generalized Chern-Simons theory, opening the perspective for its formulation as a generalized higher gauge theory.Comment: 40 page

Scattering between wobbling kinks

In this paper the scattering between a wobbling kink and a wobbling antikink in the standard $\phi^4$ model is numerically investigated. The dependence of the final velocities, wobbling amplitudes and frequencies of the scattered kinks on the collision velocity and on the initial wobbling amplitude is discussed. The fractal structure becomes more intricate due to the emergence of new resonance windows and the splitting of those arising in the non-excited kink scattering. Outside this phase the final wobbling amplitude exhibits a linear dependence of the collision velocity whereas the final frequency is a decreasing function. By contrast these magnitudes are almost independent of the initial wobbling amplitude.Comment: 20 pages, 13 figure

Wobbling kinks and shape mode interactions in a coupled two-component ϕ4\phi^4 theory

The dynamics of a wobbling kink in a two-component coupled $\phi^4$ scalar field theory (with an excited orthogonal shape mode) is addressed. For this purpose, the vibration spectrum of the second order small kink fluctuation is studied in order to find the corresponding vibration modes associated to the first (longitudinal) and second (orthogonal) field components. By means of this analysis, it was found that the number of possible shape modes depends on the value of the coupling constant. It is notable that when one of the orthogonal field shape modes is initially triggered, the unique shape mode of the longitudinal field is also activated. This coupling causes the kink to emit radiation with twice the frequency of excited mode in the first field component. Meanwhile, in the orthogonal channel we find radiation with two different frequencies: one is three times the frequency of the orthogonal wobbling mode and another is the sum of the frequencies of the longitudinal shape mode and the triggered mode. All the analytical results obtained in this study have been successfully contrasted with those obtained through numerical simulations.Comment: 20 pages, 12 figure

Introducing medical parasitology at the University of Makeni, Sierra Leone

The file attached to this record is the author's final peer reviewed version.Capacity building in Sierra Leone (West Africa) is critical to prevent potential future outbreaks similar to the 2013-16 Ebola outbreak that had devastating effects for the country and its poorly developed healthcare system. De Montfort University (DMU) in the United Kingdom (UK), in collaboration with parasitologists from the Spanish Universities of San Pablo CEU and Miguel Hernández de Elche, is leading a project to build the teaching and research capabilities of medical parasitology at the University of Makeni (UniMak, Sierra Leone). This project has two objectives: a) to introduce and enhance the teaching of medical parasitology, both theoretical and practical; and b) to implement and develop parasitology research related to important emerging human parasites such as Cryptosporidium spp. due to their public health significance. Two UniMak academics, hired to help initiate and implement the research part of the project, shared their culturally sensitive public health expertise to broker parasitology research in communities and perform a comprehensive environmental monitoring study for the detection of different emerging human parasites. The presence of targeted parasites are being studied microscopically using different staining techniques, which in turn have allowed UniMak’s academics to learn these techniques to develop new practicals in parasitology. To train UniMak’s academics and develop both parts of our project, a DMU researcher visited UniMak for two weeks in April 2019 and provided a voluntary short training course in basic parasitology, which is currently not taught in any of their programmes, and was attended by 31 students. These sessions covered basic introduction to medical parasitology and life-cycle, pathogenesis, detection, treatment and prevention of: a) coccidian parasites (Cryptosporidium, Cyclospora and Cystoisospora); b) Giardia intestinalis, Entamoeba and free-living amoebas; c) malaria and d) microsporidia. A theoretical session on common staining techniques was also provided. To facilitate the teaching and learning of these parasites, the novel resource DMU e-Parasitology was used, a package developed by the above participating universities and biomedical scientists from the UK National Health Service (NHS): http://parasitology.dmu.ac.uk/ index.htm. Following the two weeks of training, UniMak’s academics performed different curriculum modifications to the undergraduate programme ‘Public Health: Medical Laboratory Sciences’, which includes the introduction of new practicals in parasitology and changes to enhance the content of medical parasitology that will be subjected to examination. Thus, a new voluntary practical on Kinyoun stain for the detection of coccidian parasites was introduced in the final year module of ‘Medical Bacteriology and Parasitology’; eighteen students in pairs processed faecal samples from pigs provided by the Department of Agriculture and Food Security from a nearby farm. Academics at UniMak used the Kinyoun staining unit (available at http://parasitology.dmu.ac.uk/learn/lab/Kinyoun/story_html5.html; [1]) to deliver this practical. Although our project is at a preliminary stage, it has been shown to be effective in promoting the introduction and establishment of medical parasitology at UniMak and could be viewed as a case-study for other universities in low-income countries to promote the United Nations (UN) Sustainable Development Goals (SDGs) and improve public health understanding of infectious diseases