Comment on \u3ci\u3eSmall Bowel Necrosis\u3c/i\u3e

Comment on the Article Small bowel necrosis associated with postoperative jejunal tube feeding

The INTERNODES method for the treatment of non-conforming multipatch geometries in Isogeometric Analysis

In this paper we apply the INTERNODES method to solve second order elliptic problems discretized by Isogeometric Analysis methods on non-conforming multiple patches in 2D and 3D geometries. INTERNODES is an interpolation-based method that, on each interface of the configuration, exploits two independent interpolation operators to enforce the continuity of the traces and of the normal derivatives. INTERNODES supports non-conformity on NURBS spaces as well as on geometries. We specify how to set up the interpolation matrices on non-conforming interfaces, how to enforce the continuity of the normal derivatives and we give special attention to implementation aspects. The numerical results show that INTERNODES exhibits optimal convergence rate with respect to the mesh size of the NURBS spaces an that it is robust with respect to jumping coefficients.Comment: Accepted for publication in Computer Methods in Applied Mechanics and Engineerin

After Mubarak, Before Transition : The Challenges for Egypt’s Democratic Opposition

Non peer reviewedPublisher PD

Evolution of Communities with Focus on Stability

Community detection is an important tool for analyzing the social graph of mobile phone users. The problem of finding communities in static graphs has been widely studied. However, since mobile social networks evolve over time, static graph algorithms are not sufficient. To be useful in practice (e.g. when used by a telecom analyst), the stability of the partitions becomes critical. We tackle this particular use case in this paper: tracking evolution of communities in dynamic scenarios with focus on stability. We propose two modifications to a widely used static community detection algorithm: we introduce fixed nodes and preferential attachment to pre-existing communities. We then describe experiments to study the stability and quality of the resulting partitions on real-world social networks, represented by monthly call graphs for millions of subscribers.Comment: AST at 42nd JAIIO, September 16-20, 2013, Cordoba, Argentina. arXiv admin note: substantial text overlap with arXiv:1311.550

Agricultural growth and agrarian structure in the Brazilian Cerrado: the role of land prices, natural resources and technology

This paper argues that the rapid agricultural expansion of the cerrado regions in Brazil is due to the low price of land in these regions, as compared with the other agricultural regions of Brazil and abroad. This low price of land is, in turn, attributed not only to the greater distance of these regions from the main markets, but also to the limitations of natural resources (the extremely harsh drought period, which limits agricultural activities to grains and livestock) and, above all, to technological innovations that “produced†an abundance of land of good quality. In order to show more clearly how this process has taken place, the paper develops a model of the land market that allows for “production of land,†and derives the implications of such a model for production functions and total factor productivity (TFP) analyses. The paper also seeks to explain why the agrarian structure of the cerrado is so concentrated. The explanation turns on the low price of land and the peculiar characteristics of the natural resources and technology, rather than the role of agricultural policies. In its conclusions, the paper derives some implications for environmental as well as agrarian reform policies.The cerrados in Brazil, Technology, Land markets, Agricultural growth, Agrarian structure., Land Economics/Use,

Lithium solvation in dimethyl sulfoxide-acetonitrile mixtures

We present molecular dynamics simulation results pertaining to the solvation of Li+ in dimethyl sulfoxide-acetonitrile binary mixtures. The results are potentially relevant in the design of Li-air batteries that rely on aprotic mixtures as solvent media. To analyze effects derived from differences in ionic size and charge sign, the solvation of Li+ is compared to the ones observed for infinitely diluted K+ and Cl− species, in similar solutions. At all compositions, the cations are preferentially solvated by dimethyl sulfoxide. Contrasting, the first solvation shell of Cl− shows a gradual modification in its composition, which varies linearly with the global concentrations of the two solvents in the mixtures. Moreover, the energetics of the solvation, described in terms of the corresponding solute-solvent coupling, presents a clear non-ideal concentration dependence. Similar nonlinear trends were found for the stabilization of different ionic species in solution, compared to the ones exhibited by their electrically neutral counterparts. These tendencies account for the characteristics of the free energy associated to the stabilization of Li+Cl−, contact-ion-pairs in these solutions. Ionic transport is also analyzed. Dynamical results show concentration trends similar to those recently obtained from direct experimental measurements.Fil: Semino, Rocio. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química, Física de los Materiales, Medioambiente y Energía. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química, Física de los Materiales, Medioambiente y Energía; ArgentinaFil: Zaldivar, Gervasio. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química, Física de los Materiales, Medioambiente y Energía. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química, Física de los Materiales, Medioambiente y Energía; ArgentinaFil: Calvo, Ernesto Julio. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química, Física de los Materiales, Medioambiente y Energía. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química, Física de los Materiales, Medioambiente y Energía; ArgentinaFil: Laria, Daniel Hector. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química, Física de los Materiales, Medioambiente y Energía. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química, Física de los Materiales, Medioambiente y Energía; Argentina. Comisión Nacional de Energía Atómica; Argentin

Analytic Design Techniques for MPT Antenna Arrays

Solar Power Satellites (SPS) represent one of the most interesting technological opportunities to provide large scale, environmentally clean and renewable energy to the Earth [1]‐[3]. A fundamental and critical component of SPSs is the Microwave Power Transmission (MPT) system, which is responsible for the delivery of the collected solar power to the ground rectenna [2]. Towards this end, the MPT array must exhibit a narrow main beam width (), a high beam efficiency (BWBE), and a low peak sidelobe level (). Moreover, reduced realization costs and weights are also necessary [3]. To reach these contrasting goals, several design techniques have been investigated including random methods [4] and hybrid deterministic‐random approaches [2][3]. On the contrary, well‐established design tools based on stochastic optimizers [5][6] are difficult to be employed, due to their high computational costs when dealing with large arrays as those of interest in SPS [3]

L’évolution des dépenses publiques en France : loi de Wagner, cycle électoral et contrainte européenne de subsidiarité

La loi de Wagner avance l’idée de gouvernements dépensiers s’adaptant à la demande sociale ; les dépenses publiques suivent l’évolution du PIB et ne rencontrent pas de freins en période de récession. La vérification empirique du lien positif entre dépenses et PIB dans le cas de la France n’est pas validée. Les gouvernements successifs ont reconduit depuis plus d’un quart de siècle des dépenses passées, indépendamment de l’idéologie partisane avancée, et n’ont donc pas eu des logiques de redistribution mais plutôt d’allocation optimale des ressources au sens de la réduction globale des coûts de production avec comme objectif la compétitivité internationale. Les logiques de regroupement d’actionnariat éclaté et les privatisations ont concouru à cette option supply side et les cycles électoraux d’alternance politique n’ont pas marqué des différences significatives de comportements entre gouvernements de gauche et gouvernements de droite. De même, l’adhésion à l’Union européenne n’a pas de manière nette à court terme empêché des fluctuations de la dépense, non observées dans un raisonnement de long terme, mais la révolution dans l’émission de la dette, la constitution de noyaux durs, le refus du financement monétaire des déficits… constituent la lecture adéquate du lien peu robuste des dépenses publiques par rapport au PIB en France et laissent à penser, avec la loi de Wagner, que les gouvernements de la France n’ont pas eu comme préoccupation la défense d’un revenu moyen.Adolph Wagner advances the idea that public expenditure follow the evolution of GDP. This long-run relationship, qualified as low, is not verified here in the case of France. Therefore, we include other variables and particularly political facts like electoral cycles and budgetary constraints imposed by the European Union, to explain the dynamic of public expenditure in France. The successive French governments followed for more than one quarter century the trend of last expenditure independently of their ideology and thus did not have goals of redistribution, but rather of optimal allowance of the resources, according to an international competitiveness objective. The electoral cycles did not mark significant differences between the conservative governments and the left ones. The revolution in the emission of the debt, the constitution of hard cores with privatization, the refusal of the monetary financing of the deficit contributed to this option supply side