Suchergebnisse

The paper sets out how the Basque A. R. Government sees the long term planning that the PDI (Plan Director de Infraestnicturas) presupposes. It draws attention to the need to tie in initiatives on common material undertaken at national and regional levels. The article points up those initiatives that could well give rise to impugnations against the PDI's recommendations. ; Una visión de la planificación a largo plazo que propone el PDI, desde la óptica del Gobierno Vasco. El trabajo llama la atención sobre la necesidad de armonizar con las actuaciones, que sobre las mismas materias, realiza la autonomía. En el articulo se pormenorizan actuaciones que podrían dar lugar a posibles alegaciones al PDI.

Garapen iraunkorraren gaiak oihartzun mediatiko eta politiko geroz eta zabalagoa hartu duen garaiotan, trantsizio ekosozial demokratiko baterako premia aldarrikatzen da sektore akademiko, sozial eta politiko jakinetatik. Aurrekaririk gabeko erronka zibilizatorioaren aurrean, berrigituraketa materiala bezain garrantzitsu da trantsizio psikokulturalean arreta jartzea. Artikulu honetan elikadura burujabetzaren bidea hautatu duten gazteen azterketa egiten da, hiriko bizimodutik irten eta automugapenaren eta burujabetzaren ideiari jarraiki eratu dituzten esperientzietan arakatuz. Trantsizio ekosizalaren adar subjektiborako ikasgai baliagarriak ateratzea dugu helburu, bizi-esperientzia automugatuek indibiduoaren mailan dituen inpaktuak eta tentsio-puntu ezberdinak ezagutzeko batetik, eta euren jardunari eransten dioten zentzu sozialetan arakatzeko, bestetik. Interes berezia pizten du ekonomia eta subjektibotasun eredu hegemonikoaren aurrean artikulatzen ari diren bizi-praktika kontra-hegemonikoak ikertzeak, erronka sozio-ekologikorako argi puntu batzuekin topo egin dezakegula sinetsita.

El cúmulo de reformas implementadas y en proceso desde el año 2005 en Uruguay tiene un carácter estructural y conforma un cambio sustancial de las reglas de juego generales de la economía y de la sociedad uruguaya. Adicionalmente, el soporte organizacional imprescindible para que esa nueva estructura de incentivos opere efectivamente ha conducido a una reestructuración en múltiples áreas de la institucionalidad del Estado.Se hace necesario explicar por qué fue factible en Uruguay desplegar un conjunto tan relevante de reformas profundas en un corto lapso. Se aplica un enfoque de economía institucional para describir las transformaciones organizacionales y para entender cómo la institucionalidad política y el proceso de diseño e implementación afectan los resultados de las políticas públicas, además de comprender cómo esta implementación altera las condiciones y las reglas del juego original, así como el papel, los incentivos y el poder relativo de sus principales jugadores.Las reformas que apuntaron a generar nuevas estructuras de incentivos y una institucionalidad acorde para su cumplimiento tienen en su base un enfoque político-ideológico acerca del papel del Estado. Mitigar las asimetrías de información y la desigual distribución de poder económico demandan un papel compensatorio desde el aparato estatal. En la medida en que la discrecionalidad da paso a estructuras de estímulos e incentivos predeterminadas, el manejo clientelístico y elitista del poder da paso al acceso más democrático, transparente y abierto a reglas mejor especificadas.

It has been recently shown [I. Errea, B. Rousseau, and A. Bergara, Phys. Rev. Lett. 106, 165501 (2011)] that the phonons of the high-pressure simple cubic phase of calcium are stabilized by strong quantum anharmonic effects. This was obtained by a fully ab initio implementation of the self-consistent harmonic approximation including explicitly anharmonic coefficients up to fourth order. The renormalized anharmonic phonons make possible to estimate the superconducting transition temperature in this system, and a sharp agreement with experiments is found. In this work, this analysis is extended in order to study the effect of anharmonicity in the isotope effect. According to our calculations, despite the huge anharmonicity in the system, the isotope coefficient is predicted to be 0.45, close to the 0.5 value expected for a harmonic BCSsuperconductor. ; I.E. is grateful to the Department of Education, Universities and Research of the Basque Government for financial support. The authors acknowledge financial support from UPV/EHU (Grant No. IT-366-07) and the Spanish Ministry of Science and Innovation (Grant No. FIS2010-19609-C02-00). ; Peer reviewed

4 páginas, 3 figuras.-- PACS numbers: 63.20.kg, 63.20.dk, 63.20.Ry, 74.25.Kc ; The phonon spectrum of the high-pressure simple cubic phase of calcium, in the harmonic approximation, shows imaginary branches that make it mechanically unstable. In this Letter, the phonon spectrum is recalculated by using density-functional theory ab initio methods fully including anharmonic effects up to fourth order at 50 GPa. Considering that the perturbation theory cannot be employed with imaginary harmonic frequencies, a variational procedure based on the Gibbs-Bogoliubov inequality is used to estimate the renormalized phonon frequencies. The results show that strong quantum anharmonic effects make the imaginary phonons become positive even at zero temperature so that the simple cubic phase becomes mechanically stable, as experiments suggest. Moreover, our calculations find a superconducting Tc in agreement with experiments and predict an anomalous behavior of the specific heat. ; The authors are grateful to Universities and Research of the Basque Government, UPV/EHU (Grant No. IT-366-07) and the Spanish Ministry of Science and Innovation (Grant No. FIS2010-19609-C02-00) for financial support. ; Peer reviewed

5 páginas, 5 figuras.-- PACS number(s): 71.45.Gm. Trabajo presentado a "DIPC10 : Passion for Knowledge" celebrado en Donostia (España) del 27 de septiembre al 1 de octubre de 2010. ; Pressure strongly modifies electronic and optical properties of solids. In this work we report ab initio time-dependent density-functional theory calculations of the dielectric response of the high-pressure metallic phase of aluminum hydride (AlH3) within the random-phase approximation. Besides the conventional free-electronlike plasmon, which is highly damped, low-energy transitions between states near the Fermi level that appear in this metallized phase give rise to a low-energy undamped collective mode. This feature is expected to induce an abrupt edge in the experimentally measured reflectivity just below 1 eV and also affect electronic correlations close to the Fermi energy. Our work shows that AlH3 is basically a hydrogen sublattice weakly perturbed by Al atoms. ; This work was partially supported by the University of the Basque Country UPV/EHU and the Basque Government (Grants No. GIC07IT36607 and No. IT-366-07), as well as the Spanish Ministerio de Educación y Ciencia (Grant No. FIS2009-09631). Computing facilities were provided by the SGI/IZO-SGIker UPV/EHU (supported by the National Program for the Promotion of Human Resources within the National Plan of Scientific Research, Development and Innovation-Fondo Social Europeo, MCyT and the Basque Government) and by the Donostia International Physics Center (DIPC) foundation. ; Peer reviewed

This paper addresses the contradictory results obtained by Segal (1997) and Spiller and Gely (1992) concerning the impact of institutional constraints on the U.S. Supreme Court's decision making. By adapting the Spiller and Gely maximum likelihood model to the Segal dataset, we find support for the hypothesis that the Court adjusts its decisions to presidential and congressional preferences. Data from 1947 to 1992 indicate that the average probability of the Court being constrained has been approximately one‐third. Further, we show that the results obtained by Segal are the product of biases introduced by a misspecified econometric model. We also discuss how our estimation highlights the usefulness of Krehbiel's model of legislative decision making.

Recent room temperature experiments on TiH2 [Kalita, J. Appl. Phys. 108, 043511 (2010)], an important compound in hydrogen storage research, revealed a cubic (fcc, Fm-3m) to tetragonal (bct, I4/mmm) phase transition at around 0.6 GPa, which was suggested to remain stable up to at least 90 GPa. However, the simulated X-ray diffraction (XRD) pattern of the I4/mmm structure cannot explain all the diffraction peaks observed at 90 GPa. In this article, we apply the recently developed particle swarm optimization algorithm for crystal structure prediction to propose that at 63 GPa TiH2 presents a further phase transition from I4/mmm to P4/nmm, which we have also confirmed is dynamically and enthalpically stable up to 294 GPa. Moreover, the XRD patterns and calculated lattice parameters of the P4/nmm structure are in good agreement with the experimental available data. Above 294 GPa, we predict a monoclinic P21/m structure to be stable. © 2013 American Institute of Physics. ; We acknowledge funding supports from the National Natural Science Foundation of China (under Grant Nos. 91022029 and 11025418), the research fund of Key Laboratory of Surface Physics and Chemistry (No. SPC201103), and the China 973 Program under Grant No. 2011CB808200. A.B. acknowledges the Department of Education, Universities and Research of the Basque Government, UPV/EHU (Grant No. IT-366-07) and the Spanish Ministry of Science and Innovation (Grant No. FIS2010-19609-C02-00). ; Peer Reviewed

Here we present theoretical ab initio calculations based on time-dependent density-functional theory of the macroscopic dielectric function of calcium from 0 to 110 GPa in the fcc, bcc, and sc phases. All the dielectric functions are calculated using very fine reciprocal space meshes since both eigenvalues and matrix elements entering in the density-response functions are interpolated using Wannier functions. Our calculations correctly predict the energies of the low- and high-energy plasmons observed in the fcc phase at room pressure. Moreover, we predict that in the sc phase a very low-energy interband plasmon emerges at around 50 GPa that dramatically modifies the behavior of the reflectivity making it almost vanish at the plasmon energy. As a consequence, calcium becomes an example of how optical properties can become complex under pressure. © 2012 American Physical Society. ; The authors are grateful to the Department of Education, Universities and Research of the Basque Government, UPV/EHU (Grant No. IT-366-07) and the Spanish Ministry of Science and Innovation (Grant No. FIS2010-19609-C02-00) for financial support. ; Peer Reviewed

This paper addresses the contradictory results obtained by Segal (1997) and Spiller and Gely (1992) concerning the impact of institutional constraints on the U.S. Supreme Court's decision making. By adapting the Spiller and Gely maximum likelihood model to the Segal dataset, we find support for the hypothesis that the Court adjusts its decisions to presidential and congressional preferences. Data from 1947 to 1992 indicate that the average probability of the Court being constrained has been approximately one-third. Further, we show that the results obtained by Segal are the product of biases introduced by a misspecified econometric model. We also discuss how our estimation highlights the usefulness of Krehbiel's model of legislative decision making.