The effect of high-tech services offshoring on skilled employment: intra-firm evidence

The offshoring of high-tech services has greatly increased in recent years, with consequences for firms demand for skilled employment in firms. This paper specifically analyzes the relationship between R&D offshoring and the demand for R&D employment using firm-level data for Spanish manufacturing and services companies during the period 2004-2009. Estimating different specifications with panel data techniques, we find that this association is statistically positive. In particular, for services firms a 1 percentage point increase in R&D offshoring raises the demand for researchers by about 11%. This suggests the existence of complementarity among them as productive inputs

Non-equilibrium Phase-Ordering with a Global Conservation Law

In all dimensions, infinite-range Kawasaki spin exchange in a quenched Ising model leads to an asymptotic length-scale $L \sim (\rho t)^{1/2} \sim t^{1/3}$ at $T=0$ because the kinetic coefficient is renormalized by the broken-bond density, $\rho \sim L^{-1}$. For $T>0$, activated kinetics recovers the standard asymptotic growth-law, $L \sim t^{1/2}$. However, at all temperatures, infinite-range energy-transport is allowed by the spin-exchange dynamics. A better implementation of global conservation, the microcanonical Creutz algorithm, is well behaved and exhibits the standard non-conserved growth law, $L \sim t^{1/2}$, at all temperatures.Comment: 2 pages and 2 figures, uses epsf.st

Comment on ``Theory of Spinodal Decomposition''

I comment on a paper by S. B. Goryachev [PRL vol 72, p.1850 (1994)] that presents a theory of non-equilibrium dynamics for scalar systems quenched into an ordered phase. Goryachev incorrectly applies only a global conservation constraint to systems with local conservation laws.Comment: 2 pages LATeX (REVTeX macros), no figures. REVISIONS --- more to the point. microscopic example added, presentation streamlined, long-range interactions mentioned, to be published in Phys. Rev. Let

The Limitations of Simple Gene Set Enrichment Analysis Assuming Gene Independence

Since its first publication in 2003, the Gene Set Enrichment Analysis (GSEA) method, based on the Kolmogorov-Smirnov statistic, has been heavily used, modified, and also questioned. Recently a simplified approach, using a one sample t test score to assess enrichment and ignoring gene-gene correlations was proposed by Irizarry et al. 2009 as a serious contender. The argument criticizes GSEA's nonparametric nature and its use of an empirical null distribution as unnecessary and hard to compute. We refute these claims by careful consideration of the assumptions of the simplified method and its results, including a comparison with GSEA's on a large benchmark set of 50 datasets. Our results provide strong empirical evidence that gene-gene correlations cannot be ignored due to the significant variance inflation they produced on the enrichment scores and should be taken into account when estimating gene set enrichment significance. In addition, we discuss the challenges that the complex correlation structure and multi-modality of gene sets pose more generally for gene set enrichment methods.Comment: Submitted to Statistical Methods in Medical Researc

Seeing Beyond: Real-time Ultrasound Image Integration in Augmented Reality Based Telementoring

Ultrasound imaging, when aptly integrated with augmented reality based medical telementoring, may be beneficial as an assistive tool in a range of trauma procedures including removal of foreign objects from blast injuries and central or peripheral venous access. Expected benefits include reduced procedure completion time, higher efficiency, and higher incision accuracy. This paper describes the implementation strategy selected for the integration of real time ultrasound imaging in the trainee view of a telementoring system. The proposed strategy augments the view of the trainee surgeon by displaying the ultrasound image directly below and parallel to the ultrasound transducer. The developed system features a fiducial marker based tracking approach employing a triplanar geometric fixture. An experiment was designed to demonstrate the system function and validate its performance

Evaluación del impacto ambiental del uso de nanopartículas de alúmina como aditivo de mezclas biodiesel/diésel mediante análisis de ciclo de vida

(Eng) Life cycle assessment (LCA) considers the whole life cycle of a product or process, from the origin of the raw materials up to the final disposition of the wastes. In this work, LCA methodology was applied in the evaluation of the environmental impact that is caused by the use of alumina nanoparticles as an additive in biodiesel/diesel blends, considering the synthesis of the alumina nanoparticles through sol-gel method. SIMAPRO software (CML method) was used to evaluate the potential impacts of each stage of the process. Although the use of the nanoparticles caused a reduction in the emissions of CO2, SO2 and particulate material (PM); an increase in most of the impact categories (acidification, eutrophication and marine eco-toxicity) was observed during combustion. This can be attributed to the increasing emissions of NOx and the toxic effect related to the synthesis of the nanoparticles, when compared to combustion without nano-additive. These results indicated that there is a need to carry further research on the use of nanoadditives in biofuels, to verify the renewability of these alternatives regarding the sustainability of the process.(Spa) El Análisis de Ciclo de Vida (ACV) de un producto o proceso considera toda su historia, desde su origen como materia prima hasta su final como residuo. En este trabajo, se empleó la metodología ACV para evaluar el impacto ambiental por el uso de nanopartículas de alúmina como aditivo de mezclas de biodiesel-diésel, considerando la síntesis de nanopartículas de alúmina a partir del método sol-gel. La evaluación de cada etapa del proceso se realizó mediante el software SIMAPRO (método CML), para la determinación del potencial de impactos de cada una de las fases en estudio. Aunque el uso de las nanopartículas generó una reducción de las emisiones de CO2, SO2 y material particulado (MP), se observó un incremento en la mayoría de las categorías de impacto (acidificación, eutrofización y eco-toxicidad acuática marina) durante la combustión, debido al aumento en las emisiones de NOx y el efecto tóxico de la fabricación de las nanopartículas, comparado con la combustión sin el nano-aditivo, lo cual plantea el interrogante sobre si el uso de nanotecnología integrada a la industria de biocombustibles representa una alternativa realmente renovable

Estimación de propiedades del suelo a partir de espectroscopía de infrarrojo medio

La técnica de infrarrojo medio (MIR) puede ser utilizada para identificar y para estimar las propiedades de suelos, con gran precisión. El objetivo del presente estudio fue evaluar el potencial de la espectroscopia de reflectancia en el infrarrojo medio (MIR), para la estimación de algunas propiedades químicas del suelo, así como la aplicación de esta técnica, en la obtención de mapas digitales. Fueron analizadas 249 muestras de suelos de dos órdenes, correspondiente a Andisoles y Oxisoles. Los resultados obtenidos en el análisis de las curvas permiten verificar que el mayor número de atributos están reflejados en la región espectral de 400 y 850cm-1. El Andisol, se destacó por obtener mejores resultados en la calibración de los modelos que el Oxisol. Las respuestas espectrales en ambos suelos fueron similares, pero con diferentes niveles de reflectancia. Esta diferencia fue más marcada en los Andisoles, donde los picos espectrales fueron más bajos, hecho atribuible a los compuestos de la materia orgánica que tienden a oscurecer el suelo absorbiendo la luz infrarroja. Los resultados demuestran que la espectroscopia de reflectancia infrarroja MIR permite procesar una gran cantidad de muestras, donde se obtiene información sobre varios parámetros en un solo espectro. El carbono orgánico fue el atributo con la mejor predicción. De igual manera, los modelos de semivariograma, como los mapas de contorno, obtenidos a partir de los modelos con datos espectrales, mostraron alta similitud con los obtenidos a partir de las mediciones hechas en laboratorio, para aquellas propiedades, donde los modelos espectrales fueron representativos.The mid-infrared technique (MIR) can be used to identify and estimate soil properties with high accuracy. The aim of this study was to evaluate the potential of mid-infrared reflectance spectroscopy (MIR) for the estimation of chemical properties of soils as well as the application of this technique in obtaining digital maps. In this study, 249 soil samples from two orders, Andisols and Oxisols, were analyzed. The results obtained in the analysis of the curves verified that the greater number of attributes was reflected in the spectral region of 400 and 850cm-1. The Andisols stood out due to the results in the calibration of the models, which were better than those of the Oxisols. The spectral responses were similar in both soils, but with different levels of reflectivity. This difference was more notable in the Andisols, where the spectral peaks were lower, a fact attributable to the compounds of the organic matter that tended to obscure the soil, absorbing infrared light. The results demonstrated that the mid-infrared reflectance spectroscopy MIR allowed for the processing of a large number of samples, where information about various parameters was obtained in a single spectrum. The organic carbon was the attribute with the best prediction. Similarly, the semivariogram models and contour maps obtained from the spectral data models showed high similarity to those obtained from the laboratory measurements for those properties, where the spectral models were representative.Incluye referencias bibliográfic