Decentralization: Panacea or Pandora’s Box? Fiscal Perversity in Mexico.

Advocacy for decentralization has grown in Mexico at a rapid pace during the last decade. The gains of decentralization, however, are rather unclear and many times the assumptions and the outcomes of the process depart from the standard theory of fiscal federalism. There are serious drawbacks that should be considered before fully endorsing any decentralization program. As decentralization has progressed in Mexico, for instance, it has become evident that most of Mexican states have incurred in large fiscal deficits, majorly due to excessive overspending. This paper explains the reasons why such a trend has been observed in recent years based on a simultaneous equation model of state revenues and expenditures. The results suggest that increases in fiscal deficits are significantly associated with more intense political competition at the subnational sphere, the stage of the political business cycle, and fiscal perversity caused by political decentralization. This implies that regions expect to be bailed out by the federal government in case of financial trouble and thus do not have an incentive to observe fiscal discipline.decentralization, fiscal perversity, Mexico

Where are my followers? Understanding the Locality Effect in Twitter

Twitter is one of the most used applications in the current Internet with more than 200M accounts created so far. As other large-scale systems Twitter can obtain enefit by exploiting the Locality effect existing among its users. In this paper we perform the first comprehensive study of the Locality effect of Twitter. For this purpose we have collected the geographical location of around 1M Twitter users and 16M of their followers. Our results demonstrate that language and cultural characteristics determine the level of Locality expected for different countries. Those countries with a different language than English such as Brazil typically show a high intra-country Locality whereas those others where English is official or co-official language suffer from an external Locality effect. This is, their users have a larger number of followers in US than within their same country. This is produced by two reasons: first, US is the dominant country in Twitter counting with around half of the users, and second, these countries share a common language and cultural characteristics with US

Finite element formulation to study thermal stresses in nanoencapsulated phase change materials for energy storage

Nanoencapsulated phase change materials (nePCMs) – which are composed of a core with a phase change material and of a shell that envelopes the core – are currently under research for heat storage applications. Mechanically, one problem encountered in the synthesis of nePCMs is the failure of the shell due to thermal stresses during heating/cooling cycles. Thus, a compromise between shell and core volumes must be found to guarantee both mechanical reliability and heat storage capacity. At present, this compromise is commonly achieved by trial and error experiments or by using simple analytical solutions. On this ground, the current work presents a thermodynamically consistent and three-dimensional finite element (FE) formulation considering both solid and liquid phases to study thermal stresses in nePCMs. Despite the fact that there are several phase change FE formulations in the literature, the main novelty of the present work is its monolithic coupling – no staggered approaches are required – between thermal and mechanical fields. Then, the FE formulation is implemented in a computational code and it is validated against one-dimensional analytical solutions. Finally, the FE model is used to perform a thermal stress analysis for different nePCM geometries and materials to predict their mechanical failure by using Rankine’s criterion

Stochastic multi-scale models of competition within heterogeneous cellular populations: simulation methods and mean-field analysis

We propose a modelling framework to analyse the stochastic behaviour of heterogeneous, multi-scale cellular populations. We illustrate our methodology with a particular example in which we study a population with an oxygen-regulated proliferation rate. Our formulation is based on an age-dependent stochastic process. Cells within the population are characterised by their age. The age-dependent (oxygen-regulated) birth rate is given by a stochastic model of oxygen-dependent cell cycle progression. We then formulate an age-dependent birth-and-death process, which dictates the time evolution of the cell population. The population is under a feedback loop which controls its steady state size: cells consume oxygen which in turns fuels cell proliferation. We show that our stochastic model of cell cycle progression allows for heterogeneity within the cell population induced by stochastic effects. Such heterogeneous behaviour is reflected in variations in the proliferation rate. Within this set-up, we have established three main results. First, we have shown that the age to the G1/S transition, which essentially determines the birth rate, exhibits a remarkably simple scaling behaviour. This allows for a huge simplification of our numerical methodology. A further result is the observation that heterogeneous populations undergo an internal process of quasi-neutral competition. Finally, we investigated the effects of cell-cycle-phase dependent therapies (such as radiation therapy) on heterogeneous populations. In particular, we have studied the case in which the population contains a quiescent sub-population. Our mean-field analysis and numerical simulations confirm that, if the survival fraction of the therapy is too high, rescue of the quiescent population occurs. This gives rise to emergence of resistance to therapy since the rescued population is less sensitive to therapy

Kn 26, a New Quadrupolar Planetary Nebula

Once classified as an emission line source, the planetary nebula (PN) nature of the source Kn 26 has been only recently recognized in digital sky surveys. To investigate the spectral properties and spatio-kinematical structure of Kn 26, we have obtained high spatial-resolution optical and near-IR narrow-band images, high-dispersion long-slit echelle spectra, and intermediate-resolution spectroscopic observations. The new data reveal an hourglass morphology typical of bipolar PNe. A detailed analysis of its morphology and kinematics discloses the presence of a second pair of bipolar lobes, making Kn 26 a new member of the subclass of quadrupolar PNe. The time-lap between the ejection of the two pairs of bipolar lobes is much smaller than their dynamical ages, implying a rapid change of the preferential direction of the central engine. The chemical composition of Kn 26 is particularly unusual among PNe, with a low N/O ratio (as of type II PNe) and a high helium abundance (as of type I PNe), although not atypical among symbiotic stars. Such an anomalous chemical composition may have resulted from the curtail of the time in the Asymptotic Giant Branch by the evolution of the progenitor star through a common envelope phase.Comment: 9 pages, 5 figures, accepted for publication in A&

Comportamiento de la Epilepsia Generalizada con convulsión febril en niños de 6 meses a 5 años de edad atendidos en consulta externa del Hospital Infantil Manuel de Jesús Rivera, durante el período enero - diciembre del 2016.

El presente estudio tiene como objetivo determinar el Comportamiento de Epilepsia Generalizada con convulsión febril en niños de 6 meses a 5 años de edad atendidos en consulta externa del Hospital Infantil Manuel de Jesús Rivera, durante el período enero - diciembre del 2016. Se realizó un estudio descriptivo, retrospectivo, de corte transversal con una muestra seleccionada por conveniencia de 56 niños en un período de un año que cumplían con los criterios de inclusión para el estudio. Los datos encontrados se analizaron a través de estadísticas descriptivas, aplicándose frecuencias absolutas y relativas. Entre los principales resultados se encontró una edad promedio de 2 años y predominando el sexo masculino en relación al femenino con una relación de 2:1 la mayoría con procedencia urbana y esquema de vacunas completo. Los pacientes presentaron convulsiones tónico- clónicos con duración de 15 minutos con un episodio en 24 horas con recurrencia menor de 3 veces por año de convulsión febril y afebril. La mayoría de los pacientes presentó sialorrea y desviación de la mirada. Una limitación fue el registro exacto de la temperatura al momento del evento convulsivo febril con un 51.8%. Consistente con la literatura la mayoría de los reportes de tomografía y electroencefalograma son normales, sin embargo en este último encontramos hallazgos patológicos como brotes de ondas agudas de mediano voltaje, brotes de ondas agudas difusas y tendencia a ser generalizadas. Se recomienda actualizar la codificación de las enfermedades según CIE-10, además se debe realizar estudios de cohorte para una mejor comprensión de este problema de salud

Modelos de calidad aplicados al servicio de mediación en México

This article is a research that has a purely qualitative approach, part of a non-experimental design, under a cross-sectional documentary-bibliographic level. Its general objective is to analyze the main quality evaluation models and to define which of them has been applied to evaluate the mediation service in Mexico. After reviewing the literature and the documentary analysis it was determined that: The main national and international quality models have not yet been applied to evaluate the mediation service, since they are focused on assessing a general context such as the traditional justice system and other items related to the marketing of products and services. However, it was determined that the quality of the mediation service has been evaluated by standardized models developed by some academic research. It is concluded that in Mexico there is a need to implement rigorous and standardized models to evaluate the mediation service, with the aim of obtaining a national and international certification that ratifies the institutions that meet the quality standards.El presente artículo es una investigación que posee un enfoque meramente cualitativo, parte de un diseño no experimental, bajo un nivel documental-bibliográfico trasversal. Tiene por objetivo general analizar los principales modelos de evaluación de la calidad y definir cuál de ellos ha sido aplicado para evaluar el servicio de mediación en México. Tras la revisión de la literatura y el análisis documental se determinó que: Los principales modelos de calidad de índole nacional e internacional, aún no han sido aplicados para evaluar el servicio mediación, ya que están enfocados en evaluar un contexto general como lo es el sistema de justicia tradicional y otros rubros relacionados a la comercialización de productos y servicios. Sin embargo, se determinó que la calidad del servicio de mediación ha sido evaluada por modelos estandarizados, desarrollados por algunas investigaciones académicas. Se concluye que en México existe la necesidad de implementar modelos rigurosos y estandarizados encargados de evaluar al servicio de mediación, con la finalidad de obtener una certificación nacional e internacional que ratifique a las instituciones que cumplen con los estándares de calidad