500 research outputs found

    Comunidade de pesquisa global: ¿o que os padrões internacionais de coautoria dizem sobre sua estrutura?

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    Global research community represents a noteworthy object for sociological studies. In this paper we regards it as an entity with network structure and try to analyze the current state of this structure and its recent dynamics. Among the many various approaches to studying the network links that bring together the researchers all over the world, we choose to look at the structure of international co-authorship of research papers published in journals indexed by Scopus Elsevier database. We try to provide a general outline of the network structure, to reveal distinct regional clusters existing at the various levels of this structure, and to discover whatever significant changes took place in the network structure over the last 25 years.La comunidad de investigación global representa un objeto notable para los estudios sociológicos. En este documento, lo consideramos como una entidad con estructura de red e intentamos analizar el estado actual de esta estructura y su dinámica reciente. Entre los diversos enfoques para estudiar los enlaces de red que reúnen a los investigadores de todo el mundo, elegimos observar la estructura de la coautoría internacional de los trabajos de investigación publicados en revistas indexadas por la base de datos Scopus Elsevier. Intentamos proporcionar una descripción general de la estructura de la red, revelar los distintos grupos regionales que existen en los distintos niveles de esta estructura y descubrir los cambios significativos que tuvieron lugar en la estructura de la red durante los últimos 25 años.A comunidade global de pesquisa representa um objeto notável para os estudos sociológicos. Neste trabalho nós o consideramos como uma entidade com estrutura de rede e tentamos analisar o estado atual dessa estrutura e sua dinâmica recente. Entre as várias abordagens para o estudo dos links de rede que reúnem pesquisadores de todo o mundo, optamos por analisar a estrutura de coautoria internacional de trabalhos de pesquisa publicados em periódicos indexados pela base de dados Scopus Elsevier. Tentamos fornecer um esboço geral da estrutura da rede, revelar clusters regionais distintos existentes nos vários níveis dessa estrutura e descobrir as mudanças significativas ocorridas na estrutura da rede nos últimos 25 anos

    PeTTSy : a computational tool for perturbation analysis of complex systems biology models

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    Background Over the last decade sensitivity analysis techniques have been shown to be very useful to analyse complex and high dimensional Systems Biology models. However, many of the currently available toolboxes have either used parameter sampling, been focused on a restricted set of model observables of interest, studied optimisation of a objective function, or have not dealt with multiple simultaneous model parameter changes where the changes can be permanent or temporary. Results Here we introduce our new, freely downloadable toolbox, PeTTSy (Perturbation Theory Toolbox for Systems). PeTTSy is a package for MATLAB which implements a wide array of techniques for the perturbation theory and sensitivity analysis of large and complex ordinary differential equation (ODE) based models. PeTTSy is a comprehensive modelling framework that introduces a number of new approaches and that fully addresses analysis of oscillatory systems. It examines sensitivity analysis of the models to perturbations of parameters, where the perturbation timing, strength, length and overall shape can be controlled by the user. This can be done in a system-global setting, namely, the user can determine how many parameters to perturb, by how much and for how long. PeTTSy also offers the user the ability to explore the effect of the parameter perturbations on many different types of outputs: period, phase (timing of peak) and model solutions. PeTTSy can be employed on a wide range of mathematical models including free-running and forced oscillators and signalling systems. To enable experimental optimisation using the Fisher Information Matrix it efficiently allows one to combine multiple variants of a model (i.e. a model with multiple experimental conditions) in order to determine the value of new experiments. It is especially useful in the analysis of large and complex models involving many variables and parameters. Conclusions PeTTSy is a comprehensive tool for analysing large and complex models of regulatory and signalling systems. It allows for simulation and analysis of models under a variety of environmental conditions and for experimental optimisation of complex combined experiments. With its unique set of tools it makes a valuable addition to the current library of sensitivity analysis toolboxes. We believe that this software will be of great use to the wider biological, systems biology and modelling communities

    PeTTSy: a computational tool for perturbation analysis of complex systems biology models

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    Abstract Background Over the last decade sensitivity analysis techniques have been shown to be very useful to analyse complex and high dimensional Systems Biology models. However, many of the currently available toolboxes have either used parameter sampling, been focused on a restricted set of model observables of interest, studied optimisation of a objective function, or have not dealt with multiple simultaneous model parameter changes where the changes can be permanent or temporary. Results Here we introduce our new, freely downloadable toolbox, PeTTSy (Perturbation Theory Toolbox for Systems). PeTTSy is a package for MATLAB which implements a wide array of techniques for the perturbation theory and sensitivity analysis of large and complex ordinary differential equation (ODE) based models. PeTTSy is a comprehensive modelling framework that introduces a number of new approaches and that fully addresses analysis of oscillatory systems. It examines sensitivity analysis of the models to perturbations of parameters, where the perturbation timing, strength, length and overall shape can be controlled by the user. This can be done in a system-global setting, namely, the user can determine how many parameters to perturb, by how much and for how long. PeTTSy also offers the user the ability to explore the effect of the parameter perturbations on many different types of outputs: period, phase (timing of peak) and model solutions. PeTTSy can be employed on a wide range of mathematical models including free-running and forced oscillators and signalling systems. To enable experimental optimisation using the Fisher Information Matrix it efficiently allows one to combine multiple variants of a model (i.e. a model with multiple experimental conditions) in order to determine the value of new experiments. It is especially useful in the analysis of large and complex models involving many variables and parameters. Conclusions PeTTSy is a comprehensive tool for analysing large and complex models of regulatory and signalling systems. It allows for simulation and analysis of models under a variety of environmental conditions and for experimental optimisation of complex combined experiments. With its unique set of tools it makes a valuable addition to the current library of sensitivity analysis toolboxes. We believe that this software will be of great use to the wider biological, systems biology and modelling communities

    Urological care in the Chelyabinsk region

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    The article provides a general description ot Urology, Pediatric Urology and oncourological service in the Chelyabinsk region. Individually marked major urological hospitals, described the specifics of their work, the volume of operations performed. Also it reflects scientific progress urological service area.В статье приведена общая характеристика урологической, детской урологической и онкоурологической службы в Челябинской области. Отдельно отмечены основные урологические стационары, охарактеризована специфика их работы, объём выполняемых операций. Также отражен научный прогресс урологической службы области

    Crustal domains in the Western Barents Sea

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    The crustal architecture of the Barents Sea is still enigmatic due to complex evolution during the Timanian and Caledonian orogeny events, further complicated by several rifting episodes. In this study we present the new results on the crustal structure of the Caledonian–Timanian transition zone in the western Barents. We extend the work of Aarseth et al. (2017), by utilizing the seismic tomography approach to model Vp, Vs and Vp/Vs ratio, combined with the reprocessed seismic reflection line, and further complemented with gravity modelling. Based on our models we document in 3-D the position of the Caledonian nappes in the western Barents Sea. We find that the Caledonian domain is characterized by high crustal reflectivity, caused by strong deformation and/or emplacement of mafic intrusions within the crystalline crust. The Timanian domain shows semi-transparent crust with little internal reflectivity, suggesting less deformation. We find, that the eastern branch of the earlier proposed Caledonian suture, cannot be associated with the Caledonian event, but can rather be a relict from the Timanian terrane assemblance, marking one of the crustal microblocks. This crustal block may have an E–W striking southern boundary, along which the Caledonian nappes were offset. A high-velocity/density crustal body, adjacent to the Caledonian–Timanian contact zone, is interpreted as a zone of metamorphosed rocks based on the comparison with global compilations. The orientation of this body correlates with regional gravity maxima zone. Two scenarios for the origin of the body are proposed: mafic emplacement during the Timanian assembly, or massive mafic intrusions associated with the Devonian extension.publishedVersio

    Clinical anatomy of veins of the lower limbs

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    In the review are cited the given literatures on superficial and deep veins of the lower limbs. Sources, topography and places of a confluence of these veins are considered. The arrangement of the basic veins is illustrated. Data about possible variants and anomalies of superficial and deep veins are presented. The special attention is given to perforating veins

    Decision making tool for determining the points of innovation and technological development of the region

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    A research purpose is to modify the model of a patent landscape on an algorithm for the complex construction of the technological landscape, taking into account the ecological and economic features of the region. Technological landscape as a management tool for determining the points of innovation and technological development involves three basic stages. The first stage is to analyze the ecological and resource conditions in the region. The second is to build the model of the well-known patent landscape. In the third stage, identification of the chosen direction, affect investment and development opportunities are presented to support the innovation and technological development of the region. Technological landscape opportunities in the direction of iron metallurgy are constructed for the Sverdlovsk region. The methodology of building technological landscapes over time may be useful in the construction and analysis of the technological trend of the studied direction. © 2019 IOP Publishing Ltd

    Stochastic synchronization in globally coupled phase oscillators

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    Cooperative effects of periodic force and noise in globally Cooperative effects of periodic force and noise in globally coupled systems are studied using a nonlinear diffusion equation for the number density. The amplitude of the order parameter oscillation is enhanced in an intermediate range of noise strength for a globally coupled bistable system, and the order parameter oscillation is entrained to the external periodic force in an intermediate range of noise strength. These enhancement phenomena of the response of the order parameter in the deterministic equations are interpreted as stochastic resonance and stochastic synchronization in globally coupled systems.Comment: 5 figure
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