875 research outputs found

    Electroweak quark-lepton symmetry and weak topological-charge confinement in the Standard Model with Dirac neutrinos

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    The standard electroweak model with Dirac neutrinos is extended by way of the principles of electroweak quark-lepton symmetry and weak topological-charge confinement to account for quark-lepton charge relations which, if not accidental, are indicative of charge structures. A mixing in quarks and leptons of underlying integer local charges with integer weak topological charges associated with an additive group Z_3, fixed by the anomaly cancellation requirement, is discussed. It is found that the electroweak difference between topological quarks and leptons is the nonequivalence between the topological vacua of their weak field configurations, produced by a four-instanton which carries the topological charge, induces the universal fractional piece of charge distinguishing quarks from leptons, and breaks the underlying symmetry. The constituent quarks of the standard model appear as coming from topological quarks, via the weak four-instanton event. Dual transitions occur for leptons. It is shown that several other fundamental problems left open in the standard electroweak model with Dirac neutrinos are solved: the one-to-one correspondence between quark and lepton flavors, the existence of three generations, the conservation and ungauging of B-L, the electric charge quantization, and the confinement of fractional electric charges.Comment: 23 pages, 1 figure, uses IJMPA.cl

    Methodological factors involved in the study of temporal binding using the open source software Labclock Web

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    Temporal binding occurs when an action and an outcome that follows it after a short period of time are judged as occurring closer to each other in time than they actually are. This effect has often been studied using Libet’s clock methodology. Garaizar et al. (2016) presented Labclock Web, a free HTML5 open source software that allows researchers to conduct temporal binding and other experiments using Libet’s clock through the Internet. The purpose of the three experiments presented here was to test how certain methodological modifications in the Labclock Web task could impact the temporal binding effect. In comparison with the original study, we aimed to: (a) reduce the interval between action and outcome in the delayed condition to 100 ms, instead of 500, (b) present the two types of trials, immediate and delayed, in two separate consecutive blocks, instead of intermixed, (c) use a visual, rather than auditory, outcome following the action, and (d) reduce the number of trials. In addition to its potential theoretical implications, the results confirm that Labclock Web is a useful and reliable tool for conducting temporal binding experiments and that it is well suited to measure temporal binding effects in a broad range of situations

    Dynamics and structure of decaying shallow dipolar vortices

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    The current work reports on a numerical and experimental study of the evolution of decaying dipolar vortices in a shallow fluid layer. The dynamics and the structure of such vortices are investigated as a function of both their Reynolds number Re and the aspect ratio of vertical and horizontal length scales δ. By quantifying the strength of the secondary motions (vertical motions and nonzero horizontal divergence) with respect to the swirling motions of the primary vortex cores, it was found that the three-dimensionality of a shallow (δ << 1) dipolar vortex only depends on a single parameter: δ²Re. Depending on the value of this parameter, three flow regimes are observed for shallow dipolar vortices: (1) a quasi-two-dimensional regime where the structure of the dipolar vortex remains almost unchanged throughout its lifetime, (2) a transitional regime where the structure presents some three-dimensional characteristics but remains coherent, and (3) a three-dimensional regime where the structure of the dipolar vortex acquires a complicated three-dimensional shape with a persistent spanwise vortex at its front

    Inertial oscillations in a confined monopolar vortex subjected to background rotation

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    We study the axisymmetric inertial oscillations in a confined monopolar vortex under the influence of background rotation. By first focusing on the inviscid linear dynamics, and later studying the effects of viscosity and of a no-slip bottom, we characterize the effects of rotation and confinement. It was found that background rotation allows for oscillations outside the vortex core even with frequencies larger than 2O, with O the background rotation rate. However, confinement is necessary for the system to sustain oscillations with frequencies smaller than 2O. Through the analytical solution for a small perturbation of a Rankine vortex, we obtain five regimes where the oscillations are qualitatively different, depending on their frequency. Numerical results for the linear inviscid waves sustained by a Lamb–Oseen vortex show a similar behavior. The effects of viscosity are twofold: the oscillations are damped and the vortex sustaining the oscillations is modified. When a no-slip bottom is considered, a boundary layer drives a secondary motion superimposed on the inertial oscillations. In this case, the vortex is quickly damped, but the oscillations persist due to the background rotation

    The break-up of Ekman theory in a flow subjected to background rotation and driven by a non-conservative body force

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    We present an experimental/numerical study of a dipolar flow structure in a shallow layer of electrolyte driven by electromagnetic forcing and subjected to background rotation. The aim of this study is to determine the influence of a non-conservative body force on the range of applicability of the classical Ekman boundary layer theory in rapidly rotating systems. To address this question, we study the response of the flow to the three control parameters: the magnitude of the forcing, the rotation rate of the system, and the shallowness of the layer. This response is quantified taking into account the magnitude of the flow velocity (represented by the Reynolds number), the symmetry between both vortex cores, and the vertical profile of the horizontal velocity. As in the case without background rotation, the response of the flow exhibits two scaling regimes (a linear and a nonlinear regime) in which the flow exhibits different vertical profiles of velocity. The transition between the two regimes occurs when the convective acceleration becomes of the same order as the viscous damping. This suggests that the applicability of the Ekman theory depends on the existence of a balance between the forcing and the damping due to the Ekman layers and does not depend solely on the value of the Rossby number as for decaying flows. On the other hand, the cyclone/anticyclone asymmetry is governed exclusively by the Rossby number. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4766818

    ACTUACIÓN DE ENFERMERÍA ANTE EL NIÑO CON CÁNCER: PLAN DE CUIDADOS.

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    Cancer is the first cause of death in Spain. An illness which also affects younger generations and whose parents need to go through. Representing probably for them, the worst experience of their lives. In order to be able to offer a better life quality for Paediatric Oncological Patients and their families, the nurse role with their care and health treatment education to the patient and main care-giver are extremely important. In the case we are studying, we have worked on diagnosing the cases of patients, who are scared, confrontation of ineffectiveness, and nutritional disorder by default, deficient consciousness, care-giver anxiety, care-giver risk of tiredness and potential problems, nausea, and sickness. According to the rules established by Marjory Gordon and using the taxonomies NANDA (Nort American Nursing Diagnosis Association), NIC (Nursing Interventions Classification) and NOC (Nursing Outcomes Classification). This case enables us to elaborate and apply health educational programmes, focused on patients and care-givers, individually adapted to their needs.En España, el cáncer es la primera causa de muerte en términos absolutos. Una enfermedad que también afecta a la población infantil con la consiguiente ansiedad que esto provoca en los padres que se enfrentan, posiblemente, a la peor experiencia de su vida. Para poder mejorar la calidad de vida de los pacientes oncológicos pediátricos y su familia, el papel enfermero a través de los cuidados y una educación sanitaria al paciente y cuidador principal son elementos indispensables. En el caso que presentamos hemos trabajado los diagnósticos enfermeros de Temor, Afrontamiento inefectivo, Desequilibrio nutricional por defecto, Conocimientos deficientes, Ansiedad del cuidador, Riesgo de cansancio del cuidador y las complicaciones potenciales: náuseas y vómitos. Todo ello según los Patrones Funcionales de Marjory Gordon y usando las taxonomías NANDA (Nort American Nursing Diagnosis Association), NIC (Nursing Interventions Classification) y NOC (Nursing Outcomes Classification). Este caso pretende constatar la utilidad de la elaboración y aplicación de programas de educación para la salud dirigidos a los pacientes y sus cuidadores de forma individualizada y adaptada a sus propias necesidades

    Effects of eicosapentaenoic acid ethyl ester on visfatin and apelin in lean and overweight (cafeteria diet-fed) rats

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    Previous studies have demonstrated that the n-3 fatty acid EPA improves insulin resistance induced by high-fat diets. The aim of the present study was to investigate the potential role of visfatin and apelin in the insulin-sensitising effects of EPA ethyl ester. The effects of EPA on muscle and adipose GLUT mRNA, as well as on liver glucokinase (GK) and glucose-6-phosphatase (G6Pase) activity, were investigated. Male Wistar rats fed on a standard diet or a high-fat cafeteria diet were daily treated by oral administration with EPA ethyl ester (1 g/kg) for 5 weeks. A significant decrease (P,0·01) in white adipose tissue (WAT) visfatin mRNA levels was found in the cafeteria-fed rats, which was reversed by EPA administration (P,0·05). Moreover, a negative relationship was observed between homeostatic model assessment (HOMA) and the visfatin:total WAT ratio. In contrast, cafeteria-diet feeding caused a significant increase (P,0·01) in apelin mRNA in visceral WAT. EPA increased (P,0·01) apelin gene expression, and a negative relationship between HOMA index with visceral apelin mRNA and serum apelin:total WAT ratio was also observed. EPA treatment did not induce changes in skeletal muscle GLUT1, GLUT4 or insulin receptor mRNA levels. Neither liver GK and G6Pase activity nor the GK:G6Pase ratio was modified by EPA. These data suggest that somehow the insulin-sensitising effects of EPA could be related to its stimulatory action on both visfatin and apelin gene expression in visceral fat, while changes in skeletal muscle GLUT, as well as in hepatic glucose production, are not likely to be the main contributing factors in the improvement in insulin resistance induced by EPA
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