¿Es la “actualización” del modelo cubano una variante de las reformas económicas de la era soviética?

The late 1980s were the scene of transformations in the countries of the so-called "really existing" socialism in Europe, which attempted to replace the "centralized planning" scheme with a decentralized model. The process failed in all cases and, in the 1990s, the process ended up consisting in the establishment of capitalist economies, something that in Cuba's official narrative is identified as "demergerization". The experiences of China and Vietnam, which will be addressed in a forthcoming text, were very different.Los años finales de la década del 80 del siglo XX fueron el escenario de transformaciones en los países del llamado socialismo “realmente existente” de Europa, que intentaron reemplazar el esquema de “planificación centralizada” con un modelo descentralizado. El proceso fracasó en todos los casos y, en la década del 90 el proceso terminó consistiendo en el establecimiento de economías capitalistas, algo que en la narrativa oficial de Cuba se identifica como “desmerengamiento”. Las experiencias de China y Vietnam, que serán abordas en un próximo texto, fueron muy diferentes

Long-time collisionless relaxation of zonal flows in toroidal fusion devices

Tesis inédita de la Universidad Complutense de Madrid, Facultad de Ciencias Físicas, Departamento de Física Teórica I, leída el 06-07-2017Los dispositivos más prometedores para la producción de energía de fusión por confinamiento magnético son los tokamaks y stellarators. Aunque estos conceptos han sido estudiados durante décadas, hay cuestiones importantes que siguen sin entenderse. Una de estas cuestiones está relacionada con la degradación del confinamiento debido al transporte turbulento de partículas y energía producido por las microinestabilidades en el plasma. Por lo tanto, la comprensión de la física que se esconde detrás de los mecanismos que controlan estas inestabilidades es de crucial importancia para el desarrollo de futuros reactores de fusión. La reducción del transporte turbulento gracias a la acción de los flujos zonales, tanto en tokamaks como en stellarators, es un fenómeno conocido. Estos flujos están asociados a perturbaciones de potencial electrostático constantes en superficies de flujo y que tienen una estructura radial. Aunque la interacción entre la turbulencia y los flujos zonales es un proceso no lineal, el estudio de su relajación lineal proporciona una información muy útil sobre el problema y es interesante por varios motivos: Desde el punto de vista teórico, el proceso de relajación de una perturbación zonal puede describirse usando ecuaciones precisas y relativamente sencillas; podemos encontrar aproximaciones semianalíticas para entender mejor el problema físico y los resultados de las simulaciones girocinéticas; algunas de las magnitudes asociadas con el problema lineal son relevantes experimentalmente, por ejemplo la frecuencia de oscilación y los tiempos de decaimiento característicos...The most promising devices for the production of fusion energy in magnetic confinement are tokamaks and stellarators. Although these concepts have been studied for decades there are important issues that remain unsolved. One of these issues is related to the degradation of the confinement due to the turbulent transport of particles and energy produced by the microinstabilities in the plasma. Therefore, understanding the physics behind the mechanisms that control these instabilities is of crucial importance for the development of future fusion reactors. The reduction of turbulent transport by zonal flows, in tokamaks and stellarators, is a widely accepted phenomenon. These flows are associated to electrostatic potential perturbations constant on flux surfaces with a radial structure. Although the interaction between turbulence and zonal flows is a non-linear process, the study of its linear relaxation is interesting for several reasons: From the theory point of view, the relaxation process of a zonal perturbation can be described using accurate and relatively easy equations; we can find semianalytical approximations to gain insight into the physical problem and the results from gyrokinetic simulations; some quantities associated with the linear problem are experimentally relevant, for example the oscillation frequency and characteristic decay times...Depto. de Física TeóricaFac. de Ciencias FísicasTRUEpu

Semianalytical calculation of the zonal-flow oscillation frequency in stellarators

Due to their capability to reduce turbulent transport in magnetized plasmas, understanding the dynamics of zonal flows is an important problem in the fusion programme. Since the pioneering work by Rosenbluth and Hinton in axisymmetric tokamaks, it is known that studying the linear and collisionless relaxation of zonal flow perturbations gives valuable information and physical insight. Recently, the problem has been investigated in stellarators and it has been found that in these devices the relaxation process exhibits a characteristic feature: a damped oscillation. The frequency of this oscillation might be a relevant parameter in the regulation of turbulent transport, and therefore its efficient and accurate calculation is important. Although an analytical expression can be derived for the frequency, its numerical evaluation is not simple and has not been exploited systematically so far. Here, a numerical method for its evaluation is considered, and the results are compared with those obtained by calculating the frequency from gyrokinetic simulations. This "semianalytical" approach for the determination of the zonal-flow frequency reveals accurate and faster than the one based on gyrokinetic simulations.Comment: 30 pages, 14 figure

Analysing hydropower production in stressed river basins within the SEEA-W approach: the Jucar River case

[EN] Hydropower generation represents an important contribution to meeting the challenges of today's increasing world energy needs. It uses about 44% of water in Europe, and it is the main user of water in most OECD countries. However, in most cases, the energy sector is not a water consumer. The largest part of these withdrawals is immediately returned into the environment, being able to be used by other sectors, which is its most prominent characteristic. In order to understand the water-energy nexus and the challenges that the environment and other water users face, the European Commission proposed the use of water accounts in order to measure the influence of each water user, infrastructure and management decision to the total economic value of water resources in a given basin. In this sense, the SEEA-W is the most well-known approach of hybrid accounting as it provides a standard approach to compare results between different regions. This research analyses hydropower production in the Jucar River Basin (Spain), which is currently water-stressed by consumptive demands, within the SEEA-W approach. The results demonstrate that the SEEA-W approach needs some improvement in order to represent hydropower production properly.We would also like to express our gratitude to the Jucar River Basin Authority - Confederacion Hidrografica del Jucar (Spanish Ministry of Agriculture, Food and Environment) for providing data to develop this study. The authors wish to thank the Spanish Ministry of Economy and Competitiveness for its financial support through the NUTEGES project (CGL2012-34978) and ERAS project (CTM2016-77804-P). We also value the support provided by the European Community's Seventh Framework Program in financing the projects ENHANCE (FP7-ENV-2012, 308438), AGUAMOD (Interreg V-B Sudoe 2016), SWICCA (ECMRWF-Copernicus-FA 2015/C3S_441-LOT1/SMHI) and IMPREX (H2020-WATER-2014-2015, 641811).Solera Solera, A.; Pedro Monzonis, M.; Andreu Álvarez, J.; Estrela Monreal, T. (2018). Analysing hydropower production in stressed river basins within the SEEA-W approach: the Jucar River case. Hydrology Research. 49(2):528-538. https://doi.org/10.2166/nh.2017.278S528538492Andreu, J., Capilla, J., & Sanchís, E. (1996). AQUATOOL, a generalized decision-support system for water-resources planning and operational management. Journal of Hydrology, 177(3-4), 269-291. doi:10.1016/0022-1694(95)02963-xDimova, G., Tzanov, E., Ninov, P., Ribarova, I., & Kossida, M. (2014). Complementary Use of the WEAP Model to Underpin the Development of SEEAW Physical Water Use and Supply Tables. Procedia Engineering, 70, 563-572. doi:10.1016/j.proeng.2014.02.062Dincer, I. (2000). Renewable energy and sustainable development: a crucial review. Renewable and Sustainable Energy Reviews, 4(2), 157-175. doi:10.1016/s1364-0321(99)00011-8Estrela, T., Pérez-Martin, M. A., & Vargas, E. (2012). Impacts of climate change on water resources in Spain. Hydrological Sciences Journal, 57(6), 1154-1167. doi:10.1080/02626667.2012.702213Lehner, B., Czisch, G., & Vassolo, S. (2005). The impact of global change on the hydropower potential of Europe: a model-based analysis. Energy Policy, 33(7), 839-855. doi:10.1016/j.enpol.2003.10.018Molden, D., & Sakthivadivel, R. (1999). Water Accounting to Assess Use and Productivity of Water. International Journal of Water Resources Development, 15(1-2), 55-71. doi:10.1080/07900629948934Monteiro, C., Ramirez-Rosado, I. J., & Fernandez-Jimenez, L. A. (2014). Short-term forecasting model for aggregated regional hydropower generation. Energy Conversion and Management, 88, 231-238. doi:10.1016/j.enconman.2014.08.017Pedro-Monzonís, M., Jiménez-Fernández, P., Solera, A., & Jiménez-Gavilán, P. (2016). The use of AQUATOOL DSS applied to the System of Environmental-Economic Accounting for Water (SEEAW). Journal of Hydrology, 533, 1-14. doi:10.1016/j.jhydrol.2015.11.034Pedro-Monzonís, M., Solera, A., Ferrer, J., Andreu, J., & Estrela, T. (2016). Water accounting for stressed river basins based on water resources management models. Science of The Total Environment, 565, 181-190. doi:10.1016/j.scitotenv.2016.04.161Pellicer-Martínez, F., & Martínez-Paz, J. M. (2016). Grey water footprint assessment at the river basin level: Accounting method and case study in the Segura River Basin, Spain. Ecological Indicators, 60, 1173-1183. doi:10.1016/j.ecolind.2015.08.032Pereira-Cardenal, S. J., Madsen, H., Arnbjerg-Nielsen, K., Riegels, N., Jensen, R., Mo, B., … Bauer-Gottwein, P. (2014). Assessing climate change impacts on the Iberian power system using a coupled water-power model. Climatic Change, 126(3-4), 351-364. doi:10.1007/s10584-014-1221-1Pérez-Martín, M. A., Estrela, T., Andreu, J., & Ferrer, J. (2014). Modeling Water Resources and River-Aquifer Interaction in the Júcar River Basin, Spain. Water Resources Management, 28(12), 4337-4358. doi:10.1007/s11269-014-0755-3Scherer, L., & Pfister, S. (2016). Global water footprint assessment of hydropower. Renewable Energy, 99, 711-720. doi:10.1016/j.renene.2016.07.02

Hospital volume and outcomes for acute pulmonary embolism: Multinational population based cohort study

[Objectives] To evaluate the association between experience in the management of acute pulmonary embolism, reflected by hospital case volume, and mortality.[Design] Multinational population based cohort study using data from the Registro Informatizado de la Enfermedad TromboEmbólica (RIETE) registry between 1 January 2001 and 31 August 2018.[Setting] 353 hospitals in 16 countries.[Participants] 39 257 consecutive patients with confirmed diagnosis of acute symptomatic pulmonary embolism.[Main] outcome measure Pulmonary embolism related mortality within 30 days after diagnosis of the condition.[Results] Patients with acute symptomatic pulmonary embolism admitted to high volume hospitals (>40 pulmonary embolisms per year) had a higher burden of comorbidities. A significant inverse association was seen between annual hospital volume and pulmonary embolism related mortality. Admission to hospitals in the highest quarter (that is, >40 pulmonary embolisms per year) was associated with a 44% reduction in the adjusted odds of pulmonary embolism related mortality at 30 days compared with admission to hospitals in the lowest quarter (<15 pulmonary embolisms per year; adjusted risk 1.3% v 2.3%; adjusted odds ratio 0.56 (95% confidence interval 0.33 to 0.95); P=0.03). Results were consistent in all sensitivity analyses. All cause mortality at 30 days was not significantly reduced between the two quarters (adjusted odds ratio 0.78 (0.50 to 1.22); P=0.28). Survivors showed little change in the odds of recurrent venous thromboembolism (odds ratio 0.76 (0.49 to 1.19)) or major bleeding (1.07 (0.77 to 1.47)) between the low and high volume hospitals.[Conclusions] In patients with acute symptomatic pulmonary embolism, admission to high volume hospitals was associated with significant reductions in adjusted pulmonary embolism related mortality at 30 days. These findings could have implications for management strategies.Peer reviewe

Título: Sentencia 1668 07 20

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Intramolecular Interception of the Remote Position of Vinylcarbene Silver Complex Intermediates by C(sp3)−H Bond Insertion

The trapping of the elusive vinylogous position of a vinyl carbene with an aliphatic C(sp3)−H bond has been achieved for the first time during a silver-catalyzed carbene/alkyne metathesis (CAM) process. A Tpx-containing silver complex first promotes the generation of a donor-acceptor silver carbene which triggers CAM, generating a subsequent donor-donor vinyl silver carbene species, which then undergoes a selective vinylogous C(sp3)−H bond insertion, leading to the synthesis of a new family of benzoazepines. Density functional theory (DFT) calculations unveil the reaction mechanism, which allows proposing that the C−H bond insertion reaction takes place in a stepwise manner, with the hydrogen shift being the rate determining step.We are grateful for financial support from the Ministerio de Ciencia e Innovación (PGC2018-097722-B-I00, PID2020113797RB-C21 and PID2020-113711GB-I00 MCIN/AEI/ 10.13039/501100011033 and FPU grants to A.D.-J. and R.M.-C.) and the Generalitat de Catalunya (Project 2017SGR-39). We also thank Junta de Andalucía (P18-1536) and Universidad de Huelva (P.O.Feder UHU202024). A.P.Q. and A.P. are Serra Húnter Fellows and A.P. thanks ICREA Academia Prize 2019. M.A. thanks Junta de Andalucia for a postdoctoral fellowship. E.B. thanks Cátedra Cepsa-Universidad de Huelva for financial support

Modelado de ondas no lineales en fotónica, plasmónica y átomos fríos

We review the present status of the different lines of research in the area of Photonics at the Interdisciplinary Modeling Group, InterTech (www.intertech.upv.es) paying special attention to new topics that we have recently incorporated to our research interests: temporal solitons and design of supercontinuum generation, plasmon-soliton interaction, nonlinear effects of the quantum electrodynamics vacuum, and, finally, cold atoms in the mean-field and quantum regimes.En este artículo presentamos el estado actual de las diferentes líneas de investigación desarrolladas en el área de Fotónica del Grupo de Modelización Interdisciplinar, InterTech (www.intertech.upv.es) prestando especial atención a aquellas que han sido incorporadas recientemente: solitones temporales y diseño de la generación de supercontínuo, interacción plasmón-solitón, efectos no lineales del vacío en electrodinámica cuántica y, finalmente, átomos fríos en el régimen de campo medio y en el régimen cuántico.Ciencias Experimentale