Search results for "Ley"
showing 10 items of 1218 documents
Gram-scale selective synthesis of WO3−x nanorods and (NH4)xWO3 ammonium tungsten bronzes with tunable plasmonic properties
2021
Localized surface plasmon resonance properties in unconventional materials like metal oxides or chalcogenide semiconductors have been studied for use in signal detection and analysis in biomedicine and photocatalysis. We devised a selective synthesis of the tungsten oxides WO3-x and (NH4)xWO3 with tunable plasmonic properties. We selectively synthesized WO3-x nanorods with different aspect ratios and hexagonal tungsten bronzes (NH4)xWO3 as truncated nanocubes starting from ammonium metatungstate (NH4)6H2W12O40·xH2O. Both particles form from the same nuclei at temperatures >200 °C; monomer concentration and surfactant ratio are essential variables for phase selection. (NH4)xWO3 was the prefe…
Density-Functional Tight-Binding Simulations of Curvature-Controlled Layer Decoupling and Band-Gap Tuning in BilayerMoS2
2014
Monolayer transition-metal dichalcogenides (TMDCs) display valley-selective circular dichroism due to the presence of time-reversal symmetry and the absence of inversion symmetry, making them promising candidates for valleytronics. In contrast, in bilayer TMDCs both symmetries are present and these desirable valley-selective properties are lost. Here, by using density-functional tight-binding electronic structure simulations and revised periodic boundary conditions, we show that bending of bilayer MoS2 sheets breaks band degeneracies and localizes states on separate layers due to bending-induced strain gradients across the sheets. We propose a strategy for employing bending deformations in …
Optical and electronic properties of 2H−MoS2 under pressure: Revealing the spin-polarized nature of bulk electronic bands
2018
Monolayers of transition-metal dichalcogenide semiconductors present spin-valley locked electronic bands, a property with applications in valleytronics and spintronics that is usually believed to be absent in their centrosymmetric (as the bilayer or bulk) counterparts. Here we show that bulk $2\mathrm{H}\text{\ensuremath{-}}\mathrm{Mo}{\mathrm{S}}_{2}$ hides a spin-polarized nature of states determining its direct band gap, with the spin sequence of valence and conduction bands expected for its single layer. This relevant finding is attained by investigating the behavior of the binding energy of $A$ and $B$ excitons under high pressure, by means of absorption measurements and density-functi…
Dynamic Coalitional TU Games: Distributed Bargaining among Players' Neighbors
2013
We consider a sequence of transferable utility (TU) games where, at each time, the characteristic function is a random vector with realizations restricted to some set of values. The game differs from other ones in the literature on dynamic, stochastic or interval valued TU games as it combines dynamics of the game with an allocation protocol for the players that dynamically interact with each other. The protocol is an iterative and decentralized algorithm that offers a paradigmatic mathematical description of negotiation and bargaining processes. The first part of the paper contributes to the definition of a robust (coalitional) TU game and the development of a distributed bargaining protoc…
Technical and tactical analysis of women’s volleyball
2013
Summary Introduction: The study aim was to construct a technical and tactical analysis of women’s volleyball based on notational analysis in top-level and junior women’s European volleyball matches, to compare these two levels, and to clarify the differences between the winners and losers of a set. Material and Methods: Four matches from the 2010 FIVB Women’s Volleyball World Championships and 2010 CEV Junior Women’s European Championship 2010 were analyzed using Data Volley software. The number and performance level of different skills were recorded in total and were grouped according to the role of the players. Methods of scoring and attacking zones were also analyzed. Results: There were…
Los Centros de Internamiento Españoles para Adolescentes en Conflicto con la Ley: Principio de Resocialización desde la Perspectiva del Trabajo Social
2014
A pesar que la medida de privación de libertad exige una atención especial por ser la más restrictiva de derechos y dirigirse a uno de los colectivos de mayor vulnerabilidad, los menores de edad, son escasos los estudios sobre estos centros. Los centros de internamiento de medidas judiciales en España donde los adolescentes en conflicto con la ley cumplen una medida privativa de libertad no poseen un único registro donde localizarlos, son de difícil acceso y existen escasos estudios sobre ellos. En este estudio se visualizan y mapifican los recursos actuales para ejecutar la privación de libertad de menores de edad en relación al principio de resocialización que marca la Ley Orgánica 5/2000…
Occurrence of Kemp's ridley sea turtle ( Lepidochelys kempii) in the Mediterranean
2008
Recent reports of Kemp's ridley sea turtle (Lepidochelys kempii) in the Western Mediterranean calls for a re-assessment of the relative importance and the presence of this species in this sea. Different hypotheses to account for the increase in reports are discussed. The present note provides a new report of the species, a juvenile of 28 cm curved carapace length caught close to Valencia (east Spain) on 16 July 2006. Conservation measures in the area should consider this species in the near future.
Human responses to Younger Dryas in the Ebro valley and Mediterranean watershed (Eastern Spain)
2011
The archaeological and chronological records of the Ebro River valley and the Mediterranean watershed (Eastern Spain) are examined to evaluate the effects of the Younger Dryas (Greenland Stadial 1) on the foragers of an area between 36
Sevoflurane Impairs Cerebral Blood Flow Autoregulation in Rats: Reversal by Nonselective Nitric Oxide Synthase Inhibition
2005
UNLABELLED In this study, we investigated the effects of 1.0 and 2.0 minimum alveolar anesthetic concentration (MAC) sevoflurane on cerebral blood flow (CBF) autoregulation before and after nonselective inhibition of nitric oxide (NO) synthase in rats. Rats were randomly assigned as follows: Group 1 (n = 8): 1.0 MAC sevoflurane; Groups 2 and 3 (n = 8 per group): 2.0 MAC sevoflurane. Assessment of autoregulation within a mean arterial blood pressure range of 140-60 mm Hg was performed by graded hemorrhage before and after administration of l-arginine methyl ester (l-NAME, 30 mg/kg IV, Groups 1 and 2) or during hypocapnia (Group 3). In 10 additional animals, brain tissue NO(2)(-) concentratio…
Dual modulation of striatal acetylcholine release by hyperforin, a constituent of St. John's wort.
2002
Extracts of the medicinal plant St. John's wort (Hypericum perforatum) are widely used for the treatment of mild to moderate depression. Hyperforin, a constituent of St. John's wort, is known to inhibit the sodium-dependent uptake of catecholamines and amino acids into synaptic nerve endings, probably by interference with mechanisms controlling the synaptic sodium concentration. Because de novo synthesis of acetylcholine (ACh) is dependent on sodium-dependent high-affinity choline uptake, we studied the effect of hyperforin on choline (Ch) uptake in vitro and on striatal ACh release in vivo using microdialysis. In rat brain synaptosomes, hyperforin inhibited high-affinity choline uptake wit…