Spatial Logics for Bigraphs

Bigraphs are emerging as an interesting model for concurrent calculi, like CCS, pi-calculus, and Petri nets. Bigraphs are built orthogonally on two structures: a hierarchical place graph for locations and a link (hyper-)graph for connections. With the aim of describing bigraphical structures, we introduce a general framework for logics whose terms represent arrows in monoidal categories. We then instantiate the framework to bigraphical structures and obtain a logic that is a natural composition of a place graph logic and a link graph logic. We explore the concepts of separation and sharing in these logics and we prove that they generalise some known spatial logics for trees, graphs and tree contexts

Bigraphical Logics for XML

Bigraphs have been recently proposed as a meta-model for global computing resources; they are built orthogonally on two structures: a hierarchical ‘place’ graph for locations and a ‘link’ (hyper-)graph for connections. XML is now the standard meta-language for the data exchange and storage on the web. In this paper we address the similarities between bigraphs and XML and we propose bigraphs as a rich model for XML (and XML contexts). Building on this idea we proceed by investigating how the recently proposed logic of BiLog can be instantiated to describe, query and reason about web data (and web contexts)

Ultrastructural Alterations in Lepocinclis acus (Euglenophyta) Induced by Medium with High Organic Matter Content

Ultrastructural changes induced by exposure to excess of organic matter were studied in Lepocinclis acus (ex Euglena acus). The cells isolated from the Matanza River, Buenos Aires, Argentina, were grown in soil water medium (SWM). When transferred to medium enriched with Bacteriological Peptone OXOID®, marked body deformation and a significant shortening and widening of the cells was observed. These changes were unexpected in a species with quite rigid cells, a condition previously shown in studies of the pellicle fine structure. Transmission electron microscopy observations suggest that cellular deformation might be facilitated by an increase in strip number, whereas in the original strips normal ultrastructure was maintained. An increase in number and volume of paramylon grains and vacuoles, as well as the presence of membrane whorls in vacuoles was observed. The fine structure of organisms grown in medium with and without organic matter enrichment was compared, and the systematic and ecological importance of morphological changes triggered by cell deformation was discussed.Fil: Conforti, Visitacion Teresa D.. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Biodiversidad y Biología Experimental; ArgentinaFil: Ruiz, Laura Beatriz. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Biodiversidad y Biología Experimental; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Leonardi, Patricia Ines. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Centro de Recursos Naturales Renovables de la Zona Semiárida. Universidad Nacional del Sur. Centro de Recursos Naturales Renovables de la Zona Semiárida; Argentina. Universidad Nacional del Sur. Departamento de Biología, Bioquímica y Farmacia; Argentin

Static BiLog: a Unifying Language for Spatial Structures

Aiming at a unified view of the logics describing spatial structures, we introduce a general framework, BiLog, whose formulae characterise monoidal categories. As a first instance of the framework we consider bigraphs, which are emerging as a an interesting (meta-)model for spatial structures and distributed calculi. Since bigraphs are built orthogonally on two structures, a hierarchical place graph for locations and a link (hyper-)graph for connections, we obtain a logic that is a natural composition of other two instances of BiLog: a Place Graph Logic and a Link Graph Logic. We prove that these instances generalise the spatial logics for trees, for graphs and for tree contexts. We also explore the concepts of separation and sharing in these logics. We note that both the operator * of Separation Logic and the operator | of spatial logics do not completely separate the underlying structures. These two different forms of separation can be naturally derived as instances of BiLog by using the complete separation induced by the tensor product of monoidal categories along with some form of sharing

BiLog: Spatial Logics for Bigraphs

Bigraphs are emerging as a (meta-)model for concurrent calculi, like CCS, ambients, $\pi$-calculus, and Petri nets. They are built orthogonally on two structures: a hierarchical place graph for locations and a link (hyper-)graph for connections. Aiming at describing bigraphical structures, we introduce a general framework, BiLog, whose formulae describe arrows in monoidal categories. We then instantiate the framework to bigraphical structures and we obtain a logic that is a natural composition of a place graph logic and a link graph logic. We explore the concepts of separation and sharing in these logics and we prove that they generalise well known spatial logics for trees, graphs and tree contexts. As an application, we show how XML data with links and web services can be modelled by bigraphs and described by BiLog. The framework can be extended by introducing dynamics in the model and a standard temporal modality in the logic. However, in some cases, temporal modalities can be already expressed in the static framework. To testify this, we show how to encode a minimal spatial logic for CCS in an instance of BiLog

Stable Control of Pulse Speed in Parametric Three-Wave Solitons

We analyze the control of the propagation speed of three wave packets interacting in a medium with quadratic nonlinearity and dispersion. We found analytical expressions for mutually trapped pulses with a common velocity in the form of a three-parameter family of solutions of the three-wave resonant interaction. The stability of these novel parametric solitons is simply related to the value of their common group velocity

Efficiency of four-wave mixing between orthogonally polarized linear waves and solitons in a birefringent fiber

International audienceWe analyze the interaction between orthogonally polarized solitons and dispersive waves via four-wave mixing in a birefringent fiber. We calculate analytically the efficiency of the phase-sensitive scattering between orthogonally polarized soliton and dispersive wave. Experiments performed by using a photonic crystal fiber perfectly match the analytical predictions

Euclid: Superluminous supernovae in the Deep Survey

Context. In the last decade, astronomers have found a new type of supernova called superluminous supernovae (SLSNe) due to their high peak luminosity and long light-curves. These hydrogen-free explosions (SLSNe-I) can be seen to z ~ 4 and therefore, offer the possibility of probing the distant Universe. Aims. We aim to investigate the possibility of detecting SLSNe-I using ESA’s Euclid satellite, scheduled for launch in 2020. In particular, we study the Euclid Deep Survey (EDS) which will provide a unique combination of area, depth and cadence over the mission. Methods. We estimated the redshift distribution of Euclid SLSNe-I using the latest information on their rates and spectral energy distribution, as well as known Euclid instrument and survey parameters, including the cadence and depth of the EDS. To estimate the uncertainties, we calculated their distribution with two different set-ups, namely optimistic and pessimistic, adopting different star formation densities and rates. We also applied a standardization method to the peak magnitudes to create a simulated Hubble diagram to explore possible cosmological constraints. Results. We show that Euclid should detect approximately 140 high-quality SLSNe-I to z ~ 3.5 over the first five years of the mission (with an additional 70 if we lower our photometric classification criteria). This sample could revolutionize the study of SLSNe-I at z > 1 and open up their use as probes of star-formation rates, galaxy populations, the interstellar and intergalactic medium. In addition, a sample of such SLSNe-I could improve constraints on a time-dependent dark energy equation-of-state, namely w(a), when combined with local SLSNe-I and the expected SN Ia sample from the Dark Energy Survey. Conclusions. We show that Euclid will observe hundreds of SLSNe-I for free. These luminous transients will be in the Euclid data-stream and we should prepare now to identify them as they offer a new probe of the high-redshift Universe for both astrophysics and cosmology.Acknowledgements. We thank the internal EC referees (P. Nugent and J. Brichmann) as well as the many comments from our EC colleagues and friends. C.I. thanks Chris Frohmaier and Szymon Prajs for useful discussions about supernova rates. C.I. and R.C.N. thank Mark Cropper for helpful information about the V IS instrument. C.I. thanks the organisers and participants of the Munich Institute for Astro- and Particle Physics (MIAPP) workshop “Superluminous supernovae in the next decade” for stimulating discussions and the provided online material. The Euclid Consortium acknowledges the European Space Agency and the support of a number of agencies and institutes that have supported the development of Euclid. A detailed complete list is available on the Euclid web site (http://www.euclid-ec.org). In particular the Agenzia Spaziale Italiana, the Centre National dEtudes Spatiales, the Deutsches Zentrum für Luft- and Raumfahrt, the Danish Space Research Institute, the Fundação para a Ciênca e a Tecnologia, the Ministerio de Economia y Competitividad, the National Aeronautics and Space Administration, The Netherlandse Onderzoekschool Voor Astronomie, the Norvegian Space Center, the Romanian Space Agency, the State Secretariat for Education, Research and Innovation (SERI) at the Swiss Space Office (SSO), the United Kingdom Space Agency, and the University of Helsinki. R.C.N. acknowledges partial support from the UK Space Agency. D.S. acknowledges the Faculty of Technology of the University of Portsmouth for support during his PhD studies. C.I. and S.J.S. acknowledge funding from the European Research Council under the European Union’s Seventh Framework Programme (FP7/2007-2013)/ERC Grant agreement No. [291222]. C.I. and M.S. acknowledge support from EU/FP7-ERC grant No. [615929]. E.C. acknowledge financial contribution from the agreement ASI/INAF/I/023/12/0. The work by KJ and others at MPIA on NISP was supported by the Deutsches Zentrum für Luft- und Raumfahrt e.V. (DLR) under grant 50QE1202. M.B. and S.C. acknowledge financial contribution from the agreement ASI/INAF I/023/12/1. R.T. acknowledges funding from the Spanish Ministerio de Economía y Competitividad under the grant ESP2015-69020-C2- 2-R. I.T. acknowledges support from Fundação para a Ciência e a Tecnologia (FCT) through the research grant UID/FIS/04434/2013 and IF/01518/2014. J.R. was supported by JPL, which is run under a contract for NASA by Caltech and by NASA ROSES grant 12-EUCLID12-0004

COVID-19 and SARS: differences and similarities

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