El voto hispano en la precampaña electoral norteamericana 2007-2008

El presente análisis intenta describir el voto de las comunidades hispanas en la precampaña de las elecciones presidenciales en EEUU. A partir de los últimos datos demográficos de las comunidades hispanas en EEUU, el porcentaje de hispanos que tiene capacidad de participar en la elección presidencial y la posible cifra real de votantes hispanos en la misma, el análisis pone de manifiesto la relevancia de los hispanos en el panorama político norteamericano, sus preferencias políticas en las últimas décadas y el cambio de actitud electoral en la precampaña presidencial actual. La ventaja inicial de los Demócratas entre el electorado hispano no implica certeza sobre lo que finalmente los hispanos decidan en la votación presidencial, muy condicionada por el índice de participación de los jóvenes hispanos

Technic and Collaboration Breakdown Structures: Drivers of collaborative problem solving approaches in a supply chain context

Problem Solving Methodologies have been par excellence a cornerstone element of the firms’ strategy on achieving effective continuous improvement. But the enterprise evolution towards an extended environment characterized by network-based organization has radically changed the problem solving paradigms. This paper aims to propose a generic and collaborative methodology addressing more complex and distributed problems, dealing with Supply Chain issues and having a key role as a driver for building global competitive advantages and create superior performances at a Supply Chain level

Dual Farrell measures of efficiency

This paper is a revised version of an old 1982 paper by the author, partially published in Spanish as Muro and Vera (1983) and cited for example in Fare (1985). The usual disclaimer appliesThis paper provides several definitions of efficiency measures in the price space. Economic and scale aspects of inefficiency are considered to give empirical content to the measurement of efficiency when the production technology is described by cost functions models. It shows, in the Hanoch’s symmetric duality approach, how the new definitions preserve the ranking of efficiency, are formally dually symmetric to the ones defined in the input space, and both are established with respect to different descriptions of the same technology. In addition, graphical procedures are utilized to make an insight into the achievement of polar technologies from primal ones and into the relationship between Shephard’s lemma and Roy’s identity

Multiple-fault detection methodology based on vibration and current analysis applied to bearings in induction motors and gearboxes on the kinematic chain

© 2016 Juan Jose Saucedo-Dorantes et al. Gearboxes and induction motors are important components in industrial applications and their monitoring condition is critical in the industrial sector so as to reduce costs and maintenance downtimes. There are several techniques associated with the fault diagnosis in rotating machinery; however, vibration and stator currents analysis are commonly used due to their proven reliability. Indeed, vibration and current analysis provide fault condition information by means of the fault-related spectral component identification. This work presents a methodology based on vibration and current analysis for the diagnosis of wear in a gearbox and the detection of bearing defect in an induction motor both linked to the same kinematic chain; besides, the location of the fault-related components for analysis is supported by the corresponding theoretical models. The theoretical models are based on calculation of characteristic gearbox and bearings fault frequencies, in order to locate the spectral components of the faults. In this work, the influence of vibrations over the system is observed by performing motor current signal analysis to detect the presence of faults. The obtained results show the feasibility of detecting multiple faults in a kinematic chain, making the proposed methodology suitable to be used in the application of industrial machinery diagnosis.Postprint (published version

Ectopic application of the repressive histone modification H3K9me2 establishes post-zygotic reproductive isolation in Arabidopsis thaliana

Hybrid seed lethality as a consequence of interspecies or interploidy hybridizations is a major mechanism of reproductive isolation in plants. This mechanism is manifested in the endosperm, a dosage-sensitive tissue supporting embryo growth. Deregulated expression of imprinted genes such as ADMETOS (ADM) underpin the interploidy hybridization barrier in Arabidopsis thaliana; however, the mechanisms of their action remained unknown. In this study, we show that ADM interacts with the AT hook domain protein AHL10 and the SET domain-containing SU (VAR) 3-9 homolog SUVH9 and ectopically recruits the heterochromatic mark H3K9me2 to AT-rich transposable elements (TEs), causing deregulated expression of neighboring genes. Several hybrid incompatibility genes identified in Drosophila encode for dosage-sensitive heterochromatin-interacting proteins, which has led to the suggestion that hybrid incompatibilities evolve as a consequence of interspecies divergence of selfish DNA elements and their regulation. Our data show that imbalance of dosage-sensitive chromatin regulators underpins the barrier to interploidy hybridization in Arabidopsis, suggesting that reproductive isolation as a consequence of epigenetic regulation of TEs is a conserved feature in animals and plants

Homotheticity, duality and efficiency measures

This paper is a version of an old 1983 paper presented at IV Encuentro hispano-francés de economistas teóricos, Bilbao (1983). All remaining errors are our ownAs a result of the duality of cost and distance functions the efficiency of cost-minimizing behavior can be compared to shadow-prizing behaviour, and conversely. In this framework we outline the form that dual efficiency measures, Muro (1982), Muro and Vera (1983), adopt for homothetic and linearly homogeneous technologies. To illustrate the subject we provide a numerical example for a technology described by a translog cost functio

The Long Run Wage-Employment Elasticity: Evidence from Colombia

Hace algunos años, un conjunto de artículos mostró que la relación entre incrementos salariales y subida del desempleo no es clara en USA. Esta evidencia procedente de USA fue relevante para que Stiglitz opinara que la subida de un 22% del salario mínimo en España no provocaría una reducción del empleo en el año 2018. En nuestra opinión, la evidencia en USA es insuficiente para considerar que esta recomendación puede aplicarse sin más a todos los países, cualesquiera que sean sus circunstancias, Diferencias en regulaciones, instituciones y sistemas de bienestar -en especial en el seguro de desempleo-, entre otras, pueden producir alrededor del mundo diferentes resultados a los evidenciados en USA. Colombia como país en desarrollo, con instituciones que difieren de las de USA tanto en diseño como en su práctica cotidiana, es un buen ejemplo para apreciar los posibles contrastes existentes. En este artículo, analizamos los efectos sobre la demanda de empleo de una elevación de los salarios a partir de información de Colombia. Nuestro meta-análisis muestra que a largo plazo la subida de los salarios en un 1% causa una caída del 0.11% del empleo. Estos resultados son robustos aun cuando se tienen en cuenta los posibles sesgos de publicación.Several years ago, many articles showed that the relationship between wage increases and unemployment rise is not clear in the USA. This USA evidence was important to determine the recommendation of Stiglitz that a 22% increase of the minimum wage in Spain will not reduce the employment in 2018. To our view, the USA evidence is insufficient to consider that this advice can be extended to all countries. Differences in regulations, institutions and welfare systems –mainly unemployment insurance-, among others, may produce around the world different results to the expected outcome in the USA that an increase of the real wages does not provoke an unemployment rise. Colombia as a developing country, with institutions that differ in design and practice from those of the USA, could be a good testing example. In this paper, we analyse the effect of a rise in wages on the demand for employment using Colombian data. Our meta-analysis shows that a 1% real wage increment causes an 0,11% employment fall in the long run. These results stand despite publication biases

Diploma earning differences by gender in Colombia

This paper discusses the existence of diploma earnings differences by gender in Colombia with a model of sheepskin effects based on pseudo panel data for the period 1996-2000. Our results show a significant and distinctive effect of high school and university degrees among men and women. Thus, additional earnings associated with a high school degree are higher for women than for men, while additional earnings associated with a university degree are higher for men compared to women in Colombia in the period under consideration

On the size of sheepskin effects : a meta-analysis

We use information gathered from 122 studies on the effects of high school degrees on wages in different countries worldwide to carry out a meta-analysis that shows high school degrees have a statistically significant effect on wages of nearly 8%. This effect varies either when the review is made in countries away from the tropics or when factors such as sex, race, and continent are taken into account. Our results also reveal the existence of a publication bias that tends to increase the magnitude of the sheepskin effect. Nevertheless, when the former is included into the analysis the later remains statistically significant