Effect of the helicity injection rate and the Lundquist number on spheromak sustainment

The dynamics of the magnetic relaxation process during the sustainment of spheromak configurations at different helicity injection rates is studied. The three-dimensional activity is recovered using time-dependent resistive magnetohydrodynamic simulations. A cylindrical flux conserver with concentric electrodes is used to model configurations driven by a magnetized coaxial gun. Magnetic helicity is injected by tangential boundary flows. Different regimes of sustainment are identified and characterized in terms of the safety factor profile. The spatial and temporal behavior of fluctuations is described. The dynamo action is shown to be in close agreement with existing experimental data. These results are relevant to the design and operation of helicity injected devices, as well as to basic understanding of the plasma relaxation mechanism in quasi-steady state.Fil: Garcia Martinez, Pablo Luis. Universidad Nacional de Río Negro; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte; ArgentinaFil: Lampugnani, Leandro Gabriel. Comisión Nacional de Energía Atómica. Centro Atómico Bariloche; Argentina. Comisión Nacional de Energía Atómica. Gerencia del Área de Energía Nuclear. Instituto Balseiro; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte; ArgentinaFil: Farengo, Ricardo. Comisión Nacional de Energía Atómica. Gerencia del Área de Energía Nuclear. Instituto Balseiro; Argentina. Comisión Nacional de Energía Atómica. Centro Atómico Bariloche; Argentin

Spherical tokamaks with a high current carrying plasma center column

Spherical tokamaks (STs) have many advantages from the perspective of a fusion reactor. A further improvement would be to replace the center post by a plasma center column (PCC). In this case, biased electrodes could be used to drive current along the PCC and produce the toroidal magnetic field. Moreover, the magnetic helicity injected (HI) by the PCC can be used to form and sustain the configuration, via magnetic relaxation. The magnetic structure and stability of these so-called ST-PCC configurations are studied in detail. In particular, it is shown that stable equilibria with tokamak-like safety factor (q) profiles can be obtained in the regime of high PCC current and moderate poloidal flux amplification. Using numerical simulations, the feasibility of forming and sustaining ST-PCC configurations via HI is demonstrated. The sustainment in this case involves a significant level of fluctuations and is shown to occur at a marginally stable configuration having a q = 1 surface in the ST. This behavior is in close analogy to that of spheromaks sustained by a coaxial plasma gun but presents two major differences. First, the current density in the open flux region (PCC) is significantly larger. Second, the mean current density gradient in the ST has the opposite sign, leading to q profiles with regular magnetic shear (i.e., q increases from the magnetic axis to the separatrix, as in tokamaks). When helicity injection is switched off, the fluctuations decay and nested, closed magnetic surfaces appear. This opens the possibility of using HI to form the ST-PCC and a combination of auxiliary current drive (neutral beams and/or RF) and high bootstrap current to sustain a fluctuation free configuration.Fil: Lampugnani, Leandro Gabriel. Comisión Nacional de Energía Atómica. Gerencia del Área de Energía Nuclear. Instituto Balseiro; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte; Argentina. Comisión Nacional de Energía Atómica. Centro Atómico Bariloche; ArgentinaFil: Garcia Martinez, Pablo Luis. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte; Argentina. Comisión Nacional de Energía Atómica. Centro Atómico Bariloche; Argentina. Universidad Nacional de Río Negro. Sede Andina; ArgentinaFil: Farengo, Ricardo. Universidad Nacional de Río Negro. Sede Andina; Argentina. Comisión Nacional de Energía Atómica. Gerencia del Área de Energía Nuclear. Instituto Balseiro; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte; Argentin

The CORTEX Cognitive Robotics Architecture: use cases

CORTEX is a cognitive robotics architecture inspired by three key ideas: modularity, internal modelling and graph representations. CORTEX is also a computational framework designed to support early forms of intelligence in real world, human interacting robots, by selecting an a priori functional decomposition of the capabilities of the robot. This set of abilities was then translated to computational modules or agents, each one built as a network of software interconnected components. The nature of these agents can range from pure reactive modules connected to sensors and/or actuators, to pure deliberative ones, but they can only communicate with each other through a graph structure called Deep State Representation (DSR). DSR is a short-term dynamic representation of the space surrounding the robot, the objects and the humans in it, and the robot itself. All these entities are perceived and transformed into different levels of abstraction, ranging from geometric data to high-level symbolic relations such as "the person is talking and gazing at me". The combination of symbolic and geometric information endows the architecture with the potential to simulate and anticipate the outcome of the actions executed by the robot. In this paper we present recent advances in the CORTEX architecture and several real-world human-robot interaction scenarios in which they have been tested. We describe our interpretation of the ideas inspiring the architecture and the reasons why this specific computational framework is a promising architecture for the social robots of tomorrow

The role of emotional intelligence and self-care in the stress perception during COVID-19 outbreak: An intercultural moderated mediation analysis

Background: The relationship between emotional intelligence (EI) and stress has been widely studied, as well as the beneficial role of self-care to maintain health and wellbeing. However, the joint contribution of EI and self- care in predicting stress has not been examined during COVID-19 lockdown. This study aimed to examine the mediating role of self-care in the relationship between EI and stress and the potential moderator role of gender. Methods: A sample of 1082 participants from four Hispanic countries completed measures related to socio- demographic, trait emotional intelligence (Trait Meta-Mood Scale), self-care activities (Self-care Activities Screening Scale) and stress (Perceived Stress Scale). Results: Mediation analyses revealed that self-care increased the explained variance of the prediction of stress by EI dimensions after controlling gender and age. However, gender only moderated the relationship between selfcare and stress in the mediation model corresponding to emotional attention. Conclusions: Data supported a general model for the interaction of EI and self-care as contributing factors of stress. Further research is needed to replicate it in more culturally distant samples and to fully explore the po- tential role of gender differences. Future intervention programs should include a balanced combination of EI and self-care to increase their benefits on people’s healt

Canales y márgenes de comercialización de caprinos en Tejupilco y Amatepec, estado de México

Con el objetivo de analizar los canales y márgenes de comercialización de la carne de caprino, se realizó una investigación en los municipios de Tejupilco y Amatepec, Estado de México durante 2004-2005. Se determinó el canal de comercialización más utilizado por los agentes participantes de dicho mercado y se calcularon los márgenes absolutos y relativos, a través de la obtención de sus valores equivalentes y de los costos y ganancias de cada agente participante. De 133 productores entrevistados, 96.5% realiza la venta en pie. El productor obtuvo 46.5% del precio real que pagó el consumidor final por kilogramo de carne cruda y el intermediario 53.5%. Considerando la birria como producto final, el productor alcanzó 20.42% de las ganancias de todo el proceso y los intermediarios 79.58%; los birrieros obtuvieron la mayor parte (79.58%) del margen total de comercialización. El canal de comercialización más común fue productor, acopiador regional, birriero y consumidor final. Se concluye que el birriero obtuvo las mayores relaciones beneficio costo (8.86 y 8.61)

Evaluación de metodologías didácticas en trabajos de fin de grado en titulaciones de Ciencias Experimentales

Mediante encuestas a estudiantes que se encuentran finalizando el Trabajo de Fin de Grado (TFG) y profesores que dirigen de los seis grados de la facultad de Ciencias (Biología, Ciencias del Mar, Geología, Matemáticas, Óptica y Optometría, Química) de la Universidad de Alicante, se han identificado los puntos de menor fortaleza de los TFGs independientemente para cada grado. A continuación, hemos comparado los resultados entre grados para ver el nivel de similitud entre ellos y la singularidad de cada uno de ellos. A partir de ahí, hemos identificado los posibles factores que configuran cada TFG con el fin de intentar entender su singularidad en cada caso. Esta información es importante para ayudarnos a comprender cómo se podrían fortalecer posibles carencias en TFGs específicos. Con esta información y en base a la experiencia previa, proponemos medidas que permitan favorecer la implementación y desarrollo de los TFGs. Con estas propuestas se espera mejorar la eficiencia de los TFGs y conseguir un mayor nivel de satisfacción y el rendimiento en esta asignatura común en todos los grados

Análisis de los Trabajos de Fin de Grado desde la visión docente

El Trabajo Fin de Grado (TFG) en los grados de la Facultad de Ciencias, constituye una asignatura con importantes competencias transversales que representa la fase final del plan de estudios, y supone la realización por parte del estudiante de un proyecto, memoria o estudio bajo la supervisión de un tutor o tutora. En este trabajo se realiza un estudio general de los TFGs y la utilización del UA-project, desde la visión del profesorado. Para poder optimizar el desarrollo de los TFGs, en este trabajo se realizó un análisis interno mediante un cuestionario. Para dar mayor amplitud y proyección a la propuesta se han enviado los cuestionarios a profesores de todos los grados de la Facultad de Ciencias: Biología, Ciencias del Mar, Química, Geología, Matemáticas y Óptica y Optometría. Estos cuestionarios reflejan la experiencia docente obtenida en los últimos años en la tutorización de los TFGs, para así poder obtener conclusiones e ideas de mejora para su posterior aplicación

Adaptación de los TFGs de Ciencias al Espacio Europeo de Educación Superior: valoración del alumnado

Este estudio tiene el objetivo de obtener una percepción desde el punto de vista del alumnado del Trabajo de Fin de Grado (TFG). Para ello, se realizaron encuestas a estudiantes de grado que están finalizando el (TFG) en la facultad de Ciencias (Biología, Ciencias del Mar, Geología, Matemáticas, Óptica y Optometría, y Química) de la Universidad de Alicante. En un principio, se analizaron para cada grado de forma independiente con el propósito de tener una visión global de la percepción de los alumnos para cada grado. A continuación, se contrastaron los resultados obtenidos entre los grados para buscar posibles similitudes entre ellos y entender las singularidades de cada uno. Mediante este estudio podemos conocer la opinión sobre TFG desde el punto de vista del alumnado. Dichos resultados pueden sentar las bases para enriquecer y optimizar el desarrollo de los TFGs con el fin de favorecer su capacidad formativa al ser una asignatura obligatoria común en todos los grados

Autophagy-inducing peptides from mammalian VSV and fish VHSV rhabdoviral G glycoproteins (G) as models for the development of new therapeutic molecules

It has not been elucidated whether or not autophagy is induced by rhabdoviral G glycoproteins (G) in vertebrate organisms for which rhabdovirus infection is lethal. Our work provides the first evidence that both mammalian (vesicular stomatitis virus, VSV) and fish (viral hemorrhagic septicemia virus, VHSV, and spring viremia carp virus, SVCV) rhabdoviral Gs induce an autophagic antiviral program in vertebrate cell lines. The transcriptomic profiles obtained from zebrafish genetically immunized with either Gsvcv or Gvhsv suggest that autophagy is induced shortly after immunization and therefore, it may be an important component of the strong antiviral immune responses elicited by these viral proteins. Pepscan mapping of autophagy-inducing linear determinants of Gvhsv and Gvsv showed that peptides located in their fusion domains induce autophagy. Altogether these results suggest that strategies aimed at modulating autophagy could be used for the prevention and treatment of rhabdoviral infections such as rabies, which causes thousands of human deaths every year

ICF-Based Disability Survey in a Rural Population of Adults and Older Adults Living in Cinco Villas, Northeastern Spain: Design, Methods and Population Characteristics

Background: This article describes the methods of a door-to-door screening survey exploring the distribution of disability and its major determinants in northeastern Spain. This study will set the basis for the development of disability-related services for the rural elderly in northeastern Spain. Methods: The probabilistic sample was composed of 1,354 de facto residents from a population of 12,784 Social Security card holders (age: 6 50 years). Cognitive and disability screenings were conducted (period: June 2008-June 2009). Screening instruments were the MMSE and the World Health Organization Disability Assessment Schedule. Participants screened positive for disability underwent an assessment protocol focusing on primary care diagnoses, disability, lifestyle, and social and health service usage. Participants screened positive for cognitive functioning went through in-depth neurological evaluation. Results: The study sample is described. Usable data were available for 1,216 participants. A total of 625 individuals (51.4%) scored within the positive range in the disability screening, while 135 (11.1%) scored within the positive range of the cognitive screening. The proportion of positively screened individuals was higher for women and increased with age. Conclusions: Screening surveys represent a feasible design for examining the distribution of disability and its determinants among the elderly. Data quality may benefit from methodological developments tailored to rural populations with a low education level. Copyright (C) 2010 S. Karger AG, Base