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Elkouss D.,University Complutense Of Madridmadrid | Elkouss D.,Technical University of Delft | Strelchuk S.,University of Cambridge
Physical Review Letters | Year: 2015

The quantum capacity of a quantum channel is always smaller than the capacity of the channel for private communication. Both quantities are given by the infinite regularization of the coherent and the private information, respectively, which makes their evaluation very difficult. Here, we construct a family of channels for which the private and coherent information can remain strictly superadditive for unbounded number of uses, thus demonstrating that the regularization is necessary. We prove this by showing that the coherent information is strictly larger than the private information of a smaller number of uses of the channel. This implies that even though the quantum capacity is upper bounded by the private capacity, the nonregularized quantities can be interleaved. © 2015 American Physical Society.

Molina M.C.,Rey Juan Carlos University | Divakar P.K.,University Complutense Of Madridmadrid | Gonzalez N.,Rey Juan Carlos University
Mycoscience | Year: 2015

The aim of this study was to evaluate the optimum conditions for culturing Anaptychia ciliaris mycobionts in vitro and analyzing their ontogenetic development while in culture. After the testing of two germination and four development media, results of germination and growth were evaluated. We here recommend the use of basal medium without additional carbon source for germination process. Mycobiont growth was possible in all organic media tested. The maximum mycobiont growth was observed in Lilly and Barnet medium enriched with 3% glucose. © 2014 The Mycological Society of Japan. Published by Elsevier B.V. All rights reserved.

Sunyer P.,CREAF | Boixadera E.,Autonomous University of Barcelona | Munoz A.,CREAF | Munoz A.,University Complutense Of Madridmadrid | And 4 more authors.
PLoS ONE | Year: 2015

The patterns of seedling recruitment in animal-dispersed plants result from the interactions among environmental and behavioral variables. However, we know little on the contribution and combined effect of both kinds of variables. We designed a field study to assess the interplay between environment (vegetation structure, seed abundance, rodent abundance) and behavior (seed dispersal and predation by rodents, and rooting by wild boars), and their contribution to the spatial patterns of seedling recruitment in a Mediterranean mixed-oak forest. In a spatially explicit design, we monitored intensively all environmental and behavioral variables in fixed points at a small spatial scale from autumn to spring, as well as seedling emergence and survival. Our results revealed that the spatial patterns of seedling emergence were strongly related to acorn availability on the ground, but not by a facilitationeffect of vegetation cover. Rodents changed seed shadows generated by mother trees by dispersing most seeds from shrubby to open areas, but the spatial patterns of acorn dispersal/predation had no direct effect on recruitment. By contrast, rodents had a strong impact on recruitment as pilferers of cached seeds. Rooting by wild boars also reduced recruitment by reducing seed abundance, but also by changing rodent's behavior towards higher consumption of acorns in situ. Hence, seed abundance and the foraging behavior of scatter-hoarding rodents and wild boars are driving the spatial patterns of seedling recruitment in this mature oak forest, rather than vegetation features. The contribution of vegetation to seedling recruitment (e.g. facilitation by shrubs) may be context dependent, having a little role in closed forests, or being overridden by directed seed dispersal from shrubby to open areas. We warn about the need of using broad approaches that consider the combined action of environment and behavior to improve our knowledge on the dynamics of natural regeneration in forests. © 2015 Sunyer et al.

Gomez-Herrero A.,University Complutense Of Madridmadrid | Landa-Canovas A.R.,CSIC - Institute of Materials Science | Otero-Diaz L.C.,University Complutense Of Madridmadrid
Journal of Solid State Chemistry | Year: 2015

Abstract In the Sb-Nb-S system four new misfit layer phases have been found and carefully investigated via Transmission Electron Microscopy (TEM). Their structures are of composite modulated structure type with stoichiometries that can be formulated as (SbS)1+δ(NbS2)n; for n=1, δ~1.14 and 1.19; for n=2, δ~1.18 and for n=3, δ~1.19. Selected Area Electron Diffraction (SAED) patterns show an almost commensurate fit between the pseudo-tetragonal (SbS) and the pseudo-orthohexagonal (NbS2)n subcells along the misfit direction a, with 3(SbS)≈5(NbS2), being b the same for both sub-lattices and c the stacking direction. For n=1, a commensurate phase with 4aSbS=7aNbS2 has also been observed. In addition to the characteristic misfit and associated modulation of the two sub-structures, a second modulation is also present which appears to be primarily associated with the (SbS) sub-structure of both the n=1 and n=2 phases. High Resolution Transmission Electron Microscopy (HRTEM) images show ordered stacking sequences between the (SbS) and (NbS2)n lamellae for each of the four phases, however, disordered intergrowths were also occasionally found. Most of the crystals showed different kinds of twinning defects on quite a fine scale. Many crystals showed curled up edges. In some cases the lamellar crystals were entirely folded giving rise to similar diffraction patterns as found for cylindrical crystals. © 2015 Published by Elsevier Inc.

Aleja D.,Charles III University of Madrid | Lopez-Gomez J.,University Complutense Of Madridmadrid
Advanced Nonlinear Studies | Year: 2015

In this paper we characterize the dynamics of a generalized version of the model of Belgacem and Cosner [5] within the range of values of the parameters where the trivial steady state is unstable and the problem cannot admit a positive steady state. In such regimes, the dynamics is governed by the metasolutions.

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