Distributional chaotic generalized shifts

Suppose $X$ is a finite discrete space with at least two elements, $\Gamma$ is a nonempty countable set, and consider self--map $\varphi:\Gamma\to\Gamma$. We prove that the generalized shift $\sigma_\varphi:X^\Gamma\to X^\Gamma$ with $\sigma_\varphi((x_\alpha)_{\alpha\in\Gamma})=(x_{\varphi(\alpha)})_{\alpha\in\Gamma}$ (for $(x_\alpha)_{\alpha\in\Gamma}\in X^\Gamma$) is: $\bullet$ distributional chaotic (uniform, type 1, type 2) if and only if $\varphi:\Gamma\to\Gamma$ has at least a non-quasi-periodic point, $\bullet$ dense distributional chaotic if and only if $\varphi:\Gamma\to\Gamma$ does not have any periodic point, $\bullet$ transitive distributional chaotic if and only if $\varphi:\Gamma\to\Gamma$ is one--to--one without any periodic point. We complete the text by counterexamples.Comment: 13 page

Global periodicity conditions for maps and recurrences via Normal Forms

We face the problem of characterizing the periodic cases in parametric families of (real or complex) rational diffeomorphisms having a fixed point. Our approach relies on the Normal Form Theory, to obtain necessary conditions for the existence of a formal linearization of the map, and on the introduction of a suitable rational parametrization of the parameters of the family. Using these tools we can find a finite set of values p for which the map can be p-periodic, reducing the problem of finding the parameters for which the periodic cases appear to simple computations. We apply our results to several two and three dimensional classes of polynomial or rational maps. In particular we find the global periodic cases for several Lyness type recurrences.Comment: 25 page

Maria Zambrano amongst the philosophers: an introduction

This is the opening article to the monographic issue, introducing the Spanish philosopher Maria Zambrano to an Anglophone audience not familiar with her work. It covers biographical information as well as references to the main philosophical areas explored and work published by the author. In addition, it introduces the articles included in the issue and the rationale behind this special issue: to locate Zambrano’s philosophical thought alongside that of other more widely recognised thinkers in the Western world. Indeed, the articles included explore the links between Zambrano’s thought and a wide range of themes and ideas associated with other European thinkers including, Critical Theory and the Frankfurt School, Husserl and Jan Patočka’s reflections on Europe, a psychoanalytical reading of the experience of exile, a reading of the metaphor of light in the works of Zambrano through the works of Jacques Derrida y Hans Blumenberg, and present day debates around the crisis and reconstruction of the subject. Finally, the article introduces the anthology of texts by Zambrano in English translation included in the monographic issue

First Measurement of 72Ge(n,γ) at n_TOF

9th European Summer School on Experimental Nuclear AstrophysicsThe slow neutron capture process (s-process) is responsible for producing about half of the elemental abundances heavier than iron in the universo

Study of multi-neutron emission in the β-decay of 11Li

The kinematics of two-neutron emission following the β-decay of 11Li was investigated for the first time by detecting the two neutrons in coincidence and by measuring their angle and energy. An array of liquid-scintillator neutron detectors was used to reject cosmic-ray and γ-ray backgrounds by pulse-shape discrimination. Cross-talk events in which two detectors are fired by a single neutron were rejected using a filter tested on the β-1n emitter 9Li. A large cross-talk rejection rate is obtained (> 95%) over most of the energy range of interest. Application to 11Li data leads to a significant number of events interpreted as β-2n decay. A discrete neutron line at ≈ 2 MeV indicates sequential two-neutron emission, possibly from the unbound state at 10.6 MeV excitation energy in 11Be

Measurement of the 241Am neutron capture cross section at the n-TOF facility at CERN

New neutron cross section measurements of minor actinides have been performed recently in order to reduce the uncertainties in the evaluated data, which is important for the design of advanced nuclear reactors and, in particular, for determining their performance in the transmutation of nuclear waste. We have measured the 241 Am(n,γ) cross section at the n TOF facility between 0.2 eV and 10 keV with a BaF2 Total Absorption Calorimeter, and the analysis of the measurement has been recently concluded. Our results are in reasonable agreement below 20 eV with the ones published by C. Lampoudis et al. in 2013, who reported a 22% larger capture cross section up to 110 eV compared to experimental and evaluated data published before. Our results also indicate that the 241 Am(n,γ) cross section is underestimated in the present evaluated libraries between 20 eV and 2 keV by 25%, on average, and up to 35% for certain evaluations and energy ranges.Plan Nacional I+D+I FPA2014-53290-C2-1Comisión Europea, ANDES FP7- 249671Comisión Europea, CHANDA FP7-60520

Evaluación del índice de vulnerabilidad costera en la Manga del Mar Menor (Murcia, España)

© 2020. Universidad Complutense de Madrid . This document is made available under the CC-BY 4.0 license http://creativecommons.org/licenses/by /4.0/ This document is the published version of a published Work that appeared in final form in Anales de Geografía de la Universidad Complutense. To access the final edited and published work see https://doi.org/10.5209/aguc.72979Uno de los efectos más visibles del Cambio Climático es la subida del nivel del mar por el derretimiento de las masas de hielo terrestre. Para calcular la vulnerabilidad costera de la Manga del Mar Menor por la subida del nivel del mar, se ha aplicado el Índice de Vulnerabilidad Costera utilizando las variables geomorfología, pendiente de la costa, cambios en el nivel del mar, erosión costera, rango mareal, oleaje y una variable ambiental. El resultado refleja que tramos de playas de arena y las estructuras artificiales presentan mayor vulnerabilidad a los riesgos climáticos que aquellos tramos rocosos, por lo que se considera necesario la adecuación de sistemas duna-playa con vegetación natural bien conservada que constituyan una barrera frente a la energía de los temporales.- One of the most visible effects of Climate Change is the rise of sea levels by melting land ice masses. To calculate the coastal vulnerability of the Lower Sea Sleeve by sea level rise, the Coastal Vulnerability Index has been applied using geomorphology, coastal slope, sea level changes, coastal erosion, tidal range, swell and an environmental variable. The result reflects that stretches of sandy beaches and artificial structures are more vulnerable to climate risks than those rocky sections, so it is considered necessary to adapt dune-beach systems with natural vegetation well preserved that constitute a barrier to the energy of the storms.- L'un des effets les plus visibles du changement climatique est l'élévation du niveau de la mer due à la fonte des masses de glace terrestre. Pour calculer la vulnérabilité côtière de Manga del Mar Menor en raison de l'élévation du niveau de la mer, l'indice de vulnérabilité côtière a été appliqué en utilisant les variables de géomorphologie, la pente de la côte, les changements du niveau de la mer, l'érosion côtière, l'amplitude des marées, vagues et une variable environnementale. Le résultat reflète que les étendues de plages de sable et les structures artificielles sont plus vulnérables aux risques climatiques que ces étendues rocheuses, il est donc jugé nécessaire d'adapter les systèmes de dunes-plages avec une végétation naturelle bien préservée qui constitue une barrière contre la l'énergie des tempêtes

On the Lebesgue measure of Li-Yorke pairs for interval maps

We investigate the prevalence of Li-Yorke pairs for $C^2$ and $C^3$ multimodal maps $f$ with non-flat critical points. We show that every measurable scrambled set has zero Lebesgue measure and that all strongly wandering sets have zero Lebesgue measure, as does the set of pairs of asymptotic (but not asymptotically periodic) points. If $f$ is topologically mixing and has no Cantor attractor, then typical (w.r.t. two-dimensional Lebesgue measure) pairs are Li-Yorke; if additionally $f$ admits an absolutely continuous invariant probability measure (acip), then typical pairs have a dense orbit for $f \times f$. These results make use of so-called nice neighborhoods of the critical set of general multimodal maps, and hence uniformly expanding Markov induced maps, the existence of either is proved in this paper as well. For the setting where $f$ has a Cantor attractor, we present a trichotomy explaining when the set of Li-Yorke pairs and distal pairs have positive two-dimensional Lebesgue measure.Comment: 41 pages, 3 figure