Lack of Credibility, Inflation Persistence and Disinflation in Colombia

This paper measures inflation persistence in Colombia for the period1990-2010 and estimates the implied speed at which agents learn about the central bank´s inflation target. We estimate Erceg and Levin´s (2003) imperfect credibility model using Bayesian techniques and compare the posterior odds of this model against a conventional Neokeynesian model with ad-hoc price indexation. The odds are strongly in favor of the imperfect credibility model, suggesting that lack of credibility on the inflation target is an important source of inflation persistence. We use the model to compute the sacrifice ratio associated to 100 basis points inflation target shocks and find that it is (0.83%) in line with previous estimates for Colombia. We also find that the speed at which agents learn in the model has increased, albeit marginally, since the central bank implemented its inflation targeting strategy. Although during this period macroeconomic volatility has fallen, inflation persistence has remained roughly constant suggesting that, so far, the impact of those credibility gains on inflation persistence has been modest.Credibility, inflation, persistence, disinflation costs,Colombia.

El Mercado Laboral Urbano: Empleo, Desempleo y Salario Real en Colombia entre 1985 y 1996

Se estimó un modelo neo-clásico del mercado laboral, con respuestas lentas o ajustes parciales, para el caso de la evolución del empleo, el desempleo transitorio (definido como la diferencia entre el desempleo total y el permanente) y el salario real en el conjunto de las siete principales ciudades colombianas entre 1985 y 1996. Los resultados son consistentes con el modelo supuesto y, en particular, muestran que el empleo es sensible al salario real y al desempleo transitorio, y recíprocamente. Además, tanto el empleo como el desempleo transitorio y el salario real dependen simultáneamente de las tres variables exógenas incorporadas en el modelo: el producto, el costo de uso del capital y la población en edad de trabajar. En equilibrio, al cual tiende el mercado según el modelo, el desempleo transitorio es nulo, así que la tasa desempleo se hace igual a la permanente.

Prenatal development of skull and brain in a mouse model of growth restriction

Patterns of covariation result from the over-lapping effect of several developmental processes. By perturbing certain specific developmental processes, ex-perimental studies contribute to a better understanding of their particular effects on the generation of phenotype. The aim of this work was to analyze the interactions among morphological traits of the skull and the brain during late prenatal life (18.5 days postconception) in mice exposed to maternal protein undernutrition. Images from the skull and brain were obtained through micro-computed tomography and 3D landmark coordinates were digitized in order to quantify shape and size of both structures with geometric morphometric techniques. The results highlight a systemic effect of protein restriction on the size of the skull and the brain, which were both significantly reduced in the under-nourished group compared to control group. Skull shape is partially explained by brain size, and patterns of shape variation were only partially coincident with previous re-ports for other ontogenetic stages, suggesting that allomet-ric trajectories across pre- and postnatal ages change their directions. Within the skull, neurocranial and facial shape traits covaried strongly, while subtle covariation was found between the shape of the skull and the brain. These find-ings are in line with former studies in mutant mice and reveal the importance of carrying out analyses of pheno-typic variation in a broad range of developmental stages. The present study contributes to the basic understanding of epigenetic relations among growing tissues and has di-rect implications for the field of paleoanthropology, where inferences about brain morphology are usually derived from skull remains.Los patrones de covariación entre rasgos fenotí-picos resultan de la acción de diversos procesos que se sola-pan durante el desarrollo. Los estudios experimentales cons-tituyen la aproximación más adecuada para evaluar el efecto de procesos específicos en la generación de tales patrones. El objetivo de este trabajo es analizar las interacciones entre rasgos morfológicos craneofaciales y cerebrales durante la vida prenatal tardía (18,5 días posconcepción) en ratones ex-puestos a desnutrición proteica materna. Se obtuvieron imá-genes del cráneo y cerebro a partir de microtomografía com-putada y se digitalizaron landmarks en 3D para cuantificar la forma y tamaño con técnicas de morfometría geométrica. Los resultados subrayan un efecto sistémico de la restricción proteica en el tamaño del cráneo y el cerebro. La forma del cráneo es parcialmente explicable por el tamaño cerebral y los patrones de variación en forma fueron sólo en parte coin-cidentes con los reportados antes para otras edades, lo cual sugiere que las trayectorias alométricas a lo largo de la vida pre- y posnatal cambian su dirección. Los rasgos de forma del neurocráneo y el esqueleto facial covariaron fuertemen-te, aunque se encontró una asociación débil entre la forma del cráneo y del cerebro. Estos resultados concuerdan con estudios previos en ratones mutantes y revelan la relevancia de analizar la variación fenotípica en distintas etapas. El pre-sente estudio contribuye al conocimiento básico de las inte-racciones epigenéticas entre tejidos en crecimiento y tiene implicancias en el campo paleoantropológico en el que las inferencias acerca de la morfología cerebral son usualmen-te derivadas del análisis del cráneo.Fil: Barbeito Andrés, Jimena. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico CONICET- La Plata. Instituto de Genética Veterinaria "Ing. Fernando Noel Dulout". Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias. Instituto de Genética Veterinaria; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo; ArgentinaFil: Gonzalez, Paula Natalia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico CONICET- La Plata. Instituto de Genética Veterinaria "Ing. Fernando Noel Dulout". Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias. Instituto de Genética Veterinaria; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo; ArgentinaFil: Hallgrimsson, Benedikt. University of Calgary; Canad

A Service based Development Environment on Web 2.0 Platforms

Governments are investing on the IT adoption and promoting the socalled e-economies as a way to improve competitive advantages. One of the main government’s actions is to provide internet access to the most part of the population, people and organisations. Internet provides the required support for connecting organizations, people and geographically distributed developments teams. Software developments are tightly related to the availability of tools and platforms needed for products developments. Internet is becoming the most widely used platform. Software forges such as SourceForge provide an integrated tools environment gathering a set of tools that are suited for each development with a low cost. In this paper we propose an innovating approach based on Web2.0, services and a method engineering approach for software developments. This approach represents one of the possible usages of the internet of the future

Entrenamiento de fuerza en futbolistas jóvenes: hacia una óptima relación entre la magnitud de la carga y la mejora del rendimiento

In soccer, sprinting speed and vertical jump are critical skills to achieve high performance. Controversy exists about which type of training is most appropriate to improve these skills in youth players with no previous experience in programmed strength training. The aim of this study was to evaluate the efficacy and efficiency of a 16-week programme of resistance (weight) and plyometric training on sprinting and vertical and horizontal jumping in male youth soccer players. The study involved 18 soccer players, 14.1 ± 0.3 years old, with no previous experience in programmed strength training. They performed a combined cycle of resistance and plyometric training on different days, twice a week, respectively. Before and after the experimental intervention, the athletes were tested in countermovement vertical jump, bipodal horizontal jump, unipodal horizontal jump and 30 m linear sprint. After the intervention, significant improvements were observed in all the variables analyzed (p ≤ 0.05). Given that the relationship between the improvement in performance and the magnitude of the loads applied was shown to be superior to other similar interventions, it is possible to conclude that this type of training programme is both effective and efficient in the population studied.En fútbol, el sprint y el salto vertical son habilidades básicas para alcanzar el alto rendimiento. Existe controversia sobre qué tipo de entrenamiento es el más apropiado para desarrollar estas habilidades en futbolistas jóvenes sin experiencia previa con programas de entrenamiento de fuerza. El objetivo fue evaluar la eficacia y la eficiencia de un programa de 16 semanas de entrenamiento de fuerza con cargas y pliométrico sobre las carreras de velocidad y saltos verticales y horizontales en jugadores de fútbol juveniles masculinos. Participaron 18 futbolistas, de 14,1 ± 0,3 años, sin experiencia previa en entrenamiento de fuerza programado. Realizaron un ciclo combinado de entrenamiento de fuerza y pliométrico en días diferentes, dos veces por semana, respectivamente. Antes y después de la intervención experimental, los atletas fueron evaluados en salto vertical con contramovimiento, salto horizontal bipodal, salto horizontal unipodal y sprint lineal de 30 m. Se observaron mejoras significativas en todas las variables analizadas (p ≤ 0,05). Dado que la relación entre la mejora en el rendimiento y la magnitud de las cargas aplicadas se mostró superior a otras intervenciones similares, es posible concluir que este tipo de programa de entrenamiento es efectivo y eficiente en la población estudiada

Current Density Induced in the Human Body due to Power Distributions Lines using the Boundary Element Method

The paper presents the human exposure assessment to Extremely Low Frequency fields (ELF) by means of the three dimensional Boundary Element Method (BEM). The formulation is based on a rather realistic representation of the human body. The paper analizes the response of the density current due to variations on the detail of the conceptual model considered. Variations on the geometry model and the inclusion of organs have been considered. The results obtained with and without considering the rough representations of the internal organs were compared. This comparison allows to estimate their relevance in numerical modellings at ELF

Enhancement of a commercial multicopter for research in autonomous navigation

Multicopters are lightweight and maneuverable aerial vehicles yet unable to carry heavy payloads, such as large sensors or computers required for indoor autonomous navigation. Therefore, localization is usually performed by using vision-based solutions employing of either lightweight on-board cameras or external fixed cameras and a ground station for data-processing. Nevertheless, the current tendency is to use a low-power on-board computers to perform all computation on the multicopter itself. This paper covers the enhancement of a commercial multicopter, also called drone, with computation ability and sensorial devices for autonomous flight without the need of a ground-station. We describe the hardware and software integrated into the drone, which will be used for the future development of 6DoF navigation algorithms. The resulting system is able to work with most standard sensors and has the possibility to change them as needed. Also, we demonstrate the correct behavior of the drone by using a test navigation program that autonomously follows a moving beacon at constant distance and controlled altitude using an RGB-D camera and a sonar.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech