2,101 research outputs found

    Copernicus observations of Betelgeuse and Antares

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    Copernicus observations of the M-supergiants, alpha Ori and alpha Sco, are presented. The MgII h and k resonance lines are strongly in emission in both stars. The k line is highly asymmetric in both stars but the h line is symmetric. Upper limits for several other resonance lines are given for alpha Ori. The possibility is explored that the k line asymmetry is caused by overlying resonance lines of MnI and FeI formed in the cool circumstellar gas shells around these stars. Observations of the MnI 4030-4033 A lines are used to show that circumstellar shell absorption is too weak to explain the asymmetry. It is suggested that the absorption occurs in a cool turbulent region between the base of the circumstellar shell and the top of the chromosphere

    State-Corporate Crime and the Process of Capital Accumulation: mapping a global regime of permission from Galicia to Morecambe Bay

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    This paper seeks to develop the principal concerns of the state-corporate crime literature by drawing connections between two incidents that occurred 15 months apart: the sinking of the oil tanker the Prestige in Galicia in November 2002 and the killing of 24 Chinese migrant workers at Morecambe Bay in the North West of England in February 2004. It begins by introducing the key features of the two cases, before exploring how they might be described and understood as state-corporate crimes. It then identifies a tendency within the literature to analyse state-corporate crimes as ‘moments of rupture’ in the regulatory relationship. Seeking to move beyond such ‘moments of rupture’, the paper argues for an understanding of regulatory relationships as part of a broader regime of permission that seeks the smooth and uninterrupted accumulation of capital. It thus identifies the ‘process’ that must be analysed as a process of capital accumulation. This process is illustrated by focussing on the spheres of production and distribution in this story of capital accumulation. In the course of describing the complex ‘regime of permission’, the paper uncovers a structure of impunity that generally enables the most powerful architects and beneficiaries of state-corporate crime to sustain a process of capital accumulation

    Measuring dispositional cancer worry in China and Belgium: a cross-cultural validation

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    Dispositional cancer worry (DCW) is the uncontrollable tendency to dwell on cancer independent of relevant stimuli (e.g., diagnosis of the disease). Past research has suggested that DCW has two underlying dimensions: severity and frequency. Available measures of DCW severity and frequency were translated and validated in two countries: China and Belgium. Participants (N = 623) completed translated scales, as well as measures of general dispositional worry, cancer fear, and perceived risk. In both locations, DCW measures were reliable (Cronbach's alphas ranged from .78 - .93) and demonstrated strong convergent, divergent, and concurrent validity. Severity and frequency factors loaded as expected in exploratory factor analysis. Future research should pursue longitudinal tests of DCW's predictive validity and explore DCW in theoretical models predicting the relationship between worry and cancer prevention and early detection behaviors

    Perceptual properties of feedback stimuli influence the feedback‐related negativity in the flanker gambling task

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    A negative deflection in the event‐related potential is enhanced following error‐ and loss‐related feedback in decision‐making and simple gambling tasks. Researchers have assumed that the perceptual properties of the feedback stimuli are unimportant in explaining these effects. This assumption was tested in the present study through a flanker gambling task, in which the perceptual properties of the feedback were manipulated. Consistent with previous studies, loss elicited a larger feedback‐related negativity ( FRN ) than gain feedback. However, this FRN reward effect was modulated by the perceptual properties of the feedback stimuli. When gain and loss feedback were perceptually similar to each other, the enhancement of the FRN following the loss feedback was smaller compared to when the gain and loss feedback were different from each other. In addition, incongruent feedback elicited a larger FRN than congruent feedback; this FRN congruency effect was larger following gain than loss feedback. These results suggested that perceptual properties of the feedback stimuli play a role in the elicitation of the FRN .Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/108013/1/psyp12216.pd

    Switcher-random-walks: a cognitive-inspired mechanism for network exploration

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    Semantic memory is the subsystem of human memory that stores knowledge of concepts or meanings, as opposed to life specific experiences. The organization of concepts within semantic memory can be understood as a semantic network, where the concepts (nodes) are associated (linked) to others depending on perceptions, similarities, etc. Lexical access is the complementary part of this system and allows the retrieval of such organized knowledge. While conceptual information is stored under certain underlying organization (and thus gives rise to a specific topology), it is crucial to have an accurate access to any of the information units, e.g. the concepts, for efficiently retrieving semantic information for real-time needings. An example of an information retrieval process occurs in verbal fluency tasks, and it is known to involve two different mechanisms: -clustering-, or generating words within a subcategory, and, when a subcategory is exhausted, -switching- to a new subcategory. We extended this approach to random-walking on a network (clustering) in combination to jumping (switching) to any node with certain probability and derived its analytical expression based on Markov chains. Results show that this dual mechanism contributes to optimize the exploration of different network models in terms of the mean first passage time. Additionally, this cognitive inspired dual mechanism opens a new framework to better understand and evaluate exploration, propagation and transport phenomena in other complex systems where switching-like phenomena are feasible.Comment: 9 pages, 3 figures. Accepted in "International Journal of Bifurcations and Chaos": Special issue on "Modelling and Computation on Complex Networks

    The irreducible unitary representations of the extended Poincare group in (1+1) dimensions

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    We prove that the extended Poincare group in (1+1) dimensions is non-nilpotent solvable exponential, and therefore that it belongs to type I. We determine its first and second cohomology groups in order to work out a classification of the two-dimensional relativistic elementary systems. Moreover, all irreducible unitary representations of the extended Poincare group are constructed by the orbit method. The most physically interesting class of irreducible representations corresponds to the anomaly-free relativistic particle in (1+1) dimensions, which cannot be fully quantized. However, we show that the corresponding coadjoint orbit of the extended Poincare group determines a covariant maximal polynomial quantization by unbounded operators, which is enough to ensure that the associated quantum dynamical problem can be consistently solved, thus providing a physical interpretation for this particular class of representations.Comment: 12 pages, Revtex 4, letter paper; Revised version of paper published in J. Math. Phys. 45, 1156 (2004

    Psychophysiological measures of driver distraction and workload while intoxicated

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    The crash risk associated with cell phone use while driving is a contentious issue. Many states are introducing Advanced Traveler Information Systems (ATIS) that may be accessed with cell phones while driving (e.g., 511 Traveler Information Services). In these contexts, there is a need for relevant research to determine the risk of cell phone use. This study compared driver performance while conversing on a hands-free cell phone to conditions of operating common in-vehicle controls (e.g., radio, fan, air conditioning) and alcohol intoxication (BAC 0.08). In addition, the study examined the combined effects of being distracted and being intoxicated given that there may be a higher risk of a crash if the driver engages in a combination of risk factors. During simulated traffic scenarios, resource allocation was assessed through an eventrelated potential (ERP) novelty oddball paradigm. Intoxicated drivers were less attentive to all stimuli and drivers engaged in secondary tasks had weaker responses to unexpected novel sounds in brain regions associated with evaluative processing. Drivers conversing on the cell phone and in-vehicle tasks while sober had lower accuracy during the target tone task than intoxicated drivers not completing any secondary task

    Ichnological evidence of Megalosaurid Dinosaurs crossing Middle Jurassic tidal flats

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    A new dinosaur tracksite in the Vale de Meios quarry (Serra de Aire Formation, Bathonian, Portugal) preserves more than 700 theropod tracks. They are organized in at least 80 unidirectional trackways arranged in a bimodal orientation pattern (W/NW and E/SE). Quantitative and qualitative comparisons reveal that the large tridactyl, elongated and asymmetric tracks resemble the typical Late JurassicEarly Cretaceous Megalosauripus ichnogenus in all morphometric parameters. Few of the numerous tracks are preserved as elite tracks while the rest are preserved as different gradients of modified true tracks according to water content, erosive factors, radial fractures and internal overtrack formations. Taphonomical determinations are consistent with paleoenvironmental observations that indicate an inter-tidal flat located at the margin of a coastal barrier. The Megalosauripus tracks represent the oldest occurrence of this ichnotaxon and are attributed to large megalosaurid dinosaurs. Their occurrence in Vale de Meios tidal flat represents the unique paleoethological evidence of megalosaurids moving towards the lagoon, most likley during the low tide periods with feeding purposes

    EVOLUCIÓN DE LAS DIFERENCIAS SALARIALES POR SEXO EN SEIS PAÍSES DE AMÉRICA LATINA UN INTENTO DE INTERPRETACIÓN

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    Este documento analiza la evolución de las diferencias más marcadas por género en los mercados laborales de seis países de América Latina. Se estudian la participación laboral, el desempleo, las oportunidades de trabajo y los ingresos durante las dos últimas décadas del Siglo XX. Los resultados en la situación de la mujer en el Mercado laboral son mixtos: por un lado, los diferenciales de salarios por hora han disminuido significativamente, y, por otro lado, el acceso de la mujer al empleo también ha disminuido relativamente al masculino. La segmentación del mercado observada no parece ser responsable las diferencias observadas en salarios por hora. Antes bien, las diferencias observadas en salarios por hora entre hombres y mujeres parecen estar asociadas con patrones de remuneración laboral al interior de sectores y al interior de ocupaciones. El análisis realizado de regresión de ingresos sugiere que los diferenciales en salarios por hora disminuyen al aumentar el capital humano, indicando que aunque es posible que todavía queden rezagos de discriminación en contra de las mujeres, esta discriminación es estadística (a la Phelps), más que basada en prejuicios contra el género femenino. El tipo de discriminación que persiste es el basado en los roles tradicionales femeninos que todavía hacen de la mujer la más responsable por la administración del hogar y el cuidado de los hijos.diferencial salarial
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