von K\'arm\'an-Howarth equation for three-dimensional two-fluid plasmas

We derive the von K\'arm\'an-Howarth equation for a full three dimensional incompressible two-fluid plasma. In the long-time limit and for very large Reynolds numbers we obtain the equivalent of the hydrodynamic "four-fifth" law. This exact law predicts the scaling of the third-order two-point correlation functions, and puts a strong constraint on the plasma turbulent dynamics. Finally, we derive a simple expression for the 4/5 law in terms of third-order structure functions, which is appropriate for comparison with in-situ measurements in the solar wind at different spatial ranges

La contribución de la gestión humana en la salud del colaborador en la organización

Objetivo: Identificar las prácticas de gestión humana que contribuyen en la salud del colaborador de la organización -- Metodología: revisión sistemática (cualitativa-teórica) de publicaciones científicas derivadas de investigaciones y revisiones detalladas acerca de las prácticas organizacionales que contribuyen a la salud del colaborador, así como a la promoción en salud y prevención de la enfermedad en las organizaciones -- Se tomaron como fuentes bibliográficas las siguientes bases de datos: American Psychological Association, SAGE Journals, Sciencedirect y Scielo -- Los años objetivos en la búsqueda fueron 2009 a 2016, sin embargo, se retomaron algunos artículos con fechas anteriores dada la pertinencia en la temática -- Se encontraron 130 artículos utilizando los patrones de búsqueda healthy work, health at work y biopsychosocial model tanto en inglés, como en español -- Resultados: se identificó una descripción detallada de prácticas contemporáneas que se promueven desde gestión humana con el propósito de contribuir a la salud y bienestar laboral del colaborador -- Algunas de las prácticas se relacionan con el modelo biopsicosocial que expone la correlación entre en lo biológico, psicológico, social y espiritual -- Al respecto, aunque algunos artículos no hablan del modelo biopsicosocial, fundamentan las prácticas de gestión humana desde los físico y psicológico con el propósito que el colaborador alcance niveles óptimos de bienestar laboral -- Otra de las prácticas identificadas tiende a tener una mirada instrumentalista del colaborador y argumenta las prácticas desde gestión humana con el propósito de que el colaborador no enferme y así se eviten pérdidas operacionales -- Conclusión: la contribución a la salud del colaborador trasciende las obligaciones legales que tiene la organización con el colaborador, se puede hacer desde la dimensión física, psicológica, social o por la confluencia estas por medio de la promoción en salud y de la prevención de la enfermeda

Hall-MHD small-scale dynamos

Much of the progress in our understanding of dynamo mechanisms has been made within the theoretical framework of magnetohydrodynamics (MHD). However, for sufficiently diffuse media, the Hall effect eventually becomes non-negligible. We present results from three dimensional simulations of the Hall-MHD equations subjected to random non-helical forcing. We study the role of the Hall effect in the dynamo efficiency for different values of the Hall parameter, using a pseudospectral code to achieve exponentially fast convergence. We also study energy transfer rates among spatial scales to determine the relative importance of the various nonlinear effects in the dynamo process and in the energy cascade. The Hall effect produces a reduction of the direct energy cascade at scales larger than the Hall scale, and therefore leads to smaller energy dissipation rates. Finally, we present results stemming from simulations at large magnetic Prandtl numbers, which is the relevant regime in hot and diffuse media such a the interstellar medium.Comment: 11 pages and 11 figure

The importance of being mature: the effect of demographic maturation on global per-capita GDP

Given that savings behaviour and worker productivity have strong life-cycle components and given that demographic profiles vary across countries, population age structure should be linked to differences in levels of economic development. In this paper we measure the economic importance of age structure variation for the global economy. We find that even after adjusting for country-specific effects, demographic maturation has been associated with nearly half of the evolution of global per-capita GDP since 1960. We also find that age structure differences can account for just over half of the variation in worldwide per capita GDP (i.e. the lack of sigma convergence) observed since 1960. Taken as a whole, these results complement recent theoretical and empirical work on the importance of population size and economic development and reinforce empirical work linking mature demographic age structures with faster cross-country economic growth rates. JEL Classification: J13, J22, J24, O11, O40age structure, cross-country growth, life cycle savings model

Coloquio de La Habana: "Encuentro sobre la deuda externa de América Latina y el Caribe". México

El endeudamiento de América Latina, al llevar al extremo insostenible, tanto al empleo del capital externo como el pago de la deuda ya contraída, abre la puerta para que los países latinoamericanos se anticipen a la crisis generalizada, planteando, precisamente, la modificación de las relaciones económicas, es decir, el Nuevo Orden Económico Internacional, la búsqueda de un nuevo camino para el desarrollo económico que conjugue la soberanía, la autodeterminación, la democracia y el desarrollo económico y socia

Footprints in the sand: What can globular clusters tell us about NGC 4753 past?

NGC 4753 is a bright (M_V approx -22.3) lenticular galaxy. It is a very interesting target to test different theories of formation of lenticular galaxies, due to its low-density environment and complex structure. We perform the first comprehensive study of NGC 4753 globular cluster system (GCS), using Gemini/GMOS and CTIO/MosaicII images. Our results indicate a rather poor GCS of approx 1000 members. Its azimuthal distribution follows the shape of the galaxy bulge. The GC colour distribution is peculiar, presenting an intermediate subpopulation in addition to blue and red ones. This intermediate subgroup can be explained by a single stellar population with an age of 1.5-3 Gyr and 0.5-1 Z_o. The GC specific frequency S_N = 1.3+/-0.15 is surprisingly low for a galaxy of its class. The GC luminosity function (GCLF) is also peculiar, with an excess of bright GCs compared to the expected gaussian distribution. The underlying galaxy body has significant substructure, with remnants of spiral arms, dust filaments, and isophote twisting. This, and the fact that NGC 4753 hosted two type Ia SNe, support the possibility that the intermediate GC subpopulation may have originated during a recent merger, 1-3 Gyr ago.Comment: 10 pages, 10 figures, accepted on MNRA

The JONS : National Syndicalist Ideology in Spanish History and Politics

The purpose of this research was to detail the beginnings, development and ongoing impact of the Juntas De Ofensiva Nacional Sindicalistas, or National Syndicalist Action Committees, (JONS) within the context of the Spanish right during the Second Republic. The analysis focused on the JONS goals, themes and activities by looking at their ideas themselves. The numerous publications and writings of the movement and its leaders were collected. Secondary source materials from many of the most respected historians of Spain for that period were also carefully consulted as background. A critical look was taken at both the primary and secondary material to determine the overall impact and influence of the movement. The analysis proved the JONS to be a true representation of Spanish fascism. The movement had an important ideological impact on the Spanish right during the 1930\u27s as well as an ongoing legacy throughout the authoritarian regime of Francisco Franco