39,388 research outputs found

    Latitudinal trends in human primary activities: characterizing the winter day as a synchronizer

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    This work analyzes time use surveys from 19 countries (17 European and 2 American) in the middle latitude range from 38{\deg} to 61{\deg} latitude accounting for 45% of world population in that range. Time marks for primary activities (sleeping, working and eating) are systematically contrasted against light/dark conditions related to latitude. The analysis reveals that winter sunrise is a synchronizer for labor start time below 54{\deg} where they occur within the winter civil twilight region. Winter sunset is a source of synchronization for labor end times. Winter terminator also punctuate meal times in Europe with dinner times occurring 3h after winter sunset time within a strip of 1h, which is 40% narrower than variability of dinner local times. The sleep-wake cycle of laborers in a weekday is shown to be related to winter sunrise whereas standard population's cycle appears to be irrespective of latitude. The significance of the winter terminator depends on two competing factors average daily labor time (some 7h30m) and winter daytime ---the shortest photoperiod---. Winter terminator gains significance when shortest photoperiod roughly matches to daily labor time plus a reasonable lunch break. That is within a latitude range from 38{\deg} to 54{\deg}. The significance of winter terminator as a source of synchronization is also related to contemporary year round time schedules: the shortest photoperiod represents the worst case scenario the society faces. Average daily sleep times show little trend with the shortest photoperiod slope 5min/h for a Pearson coefficient r2=0.242r^2=0.242. Average labor time may have a weak coupling with the shortest photoperiod: slope 29min/h for r2=0.338r^2=0.338.Comment: Changes: Descriptive statistics and bivariate correlations added. Introduction, Results and Discussion largely modified. RevTeX4-1 27 pages, 6 figures, 13 tables. Data from Time Use Surveys, Hetus and Eurosta

    Isolation and social instigation in animal models of aggression: effects of an mGLU1 receptor antagonist administration

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    Isolate-induced aggression in male mice is a model widely used in psychoparmacology of aggression. Animals are usually isolated for 30 days and subsequently treated and confronted with an anosmic opponent in a neutral area. For 10 min, the complete agonistic repertoire exhibited by the experimental animals is examined, allowing a detailed analysis of aggressive behaviors and other exploratory and motor behaviors. We have recently investigated the role of glutamate metabotropic receptors (mGluR) in this experimental model. Glutamate is the major excitatory neurotransmitter in the brain and it acts both at ionotropic (NMDA, AMPA and kainate receptors) and mGluRs, which are members of the G-protein-coupled receptor family. Eight mGluRs have been characterized and grouped into three classes: group I (mGlu1 and 5), group II (mGlu2 and 3) and group III (mGlu4, 6, 7 and 8). We have tested selective ligands available for the subtypes of mGluRs. Group I antagonists were the most effective ones reducing aggression, being especially remarkable the antiaggressive action observed after the administration of JNJ16259685 (an mGlu1 selective antagonist; 0.125-8 mg/kg i.p.), that produced a strong reduction of offensive behaviors (threat and attack), without affecting immobility with all doses. In this context, we wonder whether this drug could also reduce forms of intensified-heightened aggression. In recent years there is an increasing interest in studying excessive-abnormal forms of aggression in rodents, with the aim of providing a higher translational value to the observed violence in humans, in which aggression becomes intense, disproportionate and dysfunctional. We select a social instigation model, where mice are exposed to a brief territory intrusion of an adult male mice physically inaccessible. After this social provocation mice are exposed to a second opponent which now is unprotected. Social instigation dramatically increases aggressive behaviors, which renders this model appropriate for investigating the neurobiological mechanisms of excessive aggressive behavior. Therefore, we implemented a social instigation procedure in the isolation-induced aggression model with a double objective: first, to examine whether “instigation” could increase the aggression obtained by social isolation; and second, to evaluate the antiaggressive effect of an mGlu1 antagonist in heightened aggression. For this purpose, an acute dose of JNJ16259685 (0.5 mg/kg) was administrated to socially instigated animals after isolation, as well as to animals only isolated. Our results revealed that social instigation reduced latency of attack and increased the frequency and duration of attacks against not instigated animals, without affecting motor behaviors. Likewise, JNJ16259685 (0.5 mg/kg) administration significantly reduced aggressive behaviors in both cases. Taken together, this study shows that social instigation is an useful experimental procedure that increases significantly the levels of aggression observed in an isolated-induced aggression model, also demonstrating the involvement of mGlu1 receptors in the modulation of normal and heightened aggression in male mice.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

    Particle-based and Meshless Methods with Aboria

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    Aboria is a powerful and flexible C++ library for the implementation of particle-based numerical methods. The particles in such methods can represent actual particles (e.g. Molecular Dynamics) or abstract particles used to discretise a continuous function over a domain (e.g. Radial Basis Functions). Aboria provides a particle container, compatible with the Standard Template Library, spatial search data structures, and a Domain Specific Language to specify non-linear operators on the particle set. This paper gives an overview of Aboria's design, an example of use, and a performance benchmark

    The Measurement of Adequacy and Coverage in Decentralized Minimum Income Schemes: An Application to Spanish Regions

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    The existing literature on welfare decentralization has not produced a robust set of measures and properties and no consensus has emerged on how inequalities arising from welfare decentralization should be aggregated into a composite index. The measurement of the global effects on inequality has usually focused on one of two dimensions: adequacy and coverage. The orderings of regions or the levels of inter-regional inequality can be very different depending on the chosen outcome. In this paper we propose new approaches that may contribute to the development of a more comprehensive picture of these types of inequality. First, we propose new measures combining both dimensions. Second, we propose to measure the contribution of each region to inequality making use of the Gini index and the interpretation of this inequality measure in terms of deprivation. Third, we provide an interpretation of the decomposition of the change in welfare inequalities in terms of progressivity and re-ranking components. Fourth, we analyze the notions of inequality and convergence considering adequacy, coverage and a measure that combines both dimensions under a unified framework.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

    Macro-routing: a new hierarchical routing protocol

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    In a continually evolving Internet, tools such as quality of service routing must be used in order to accommodate user demands. QoS routing raises scalability issues within very large networks, which can he avoided by using hierarchical routing strategies. However, such strategies can lead to inaccurate path selection due to the aggregation process. To avoid such problems, we propose a hierarchical routing protocol, called macro-routing, which can distribute the route computation more efficiently throughout the network using mobile agents. It processes more detailed information than conventional hierarchical routing protocols, so is more likely to find the best path between source and destination. Also, by using mobile agents, more than one available path can be found. This provides a fast recovery mechanism, where no protocol restart is needed in a failure situation
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