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Este artículo contiene 7 páginas, 4 figuras. ; The study of spatial patterns in the distribution of organisms is a central issue in ecology. Here we address the question of whether predator–prey interactions can induce nonuniform distributions. We study how diffusion affects the stability of predator– prey coexistence equilibria and show a new difference between ratio- and prey-dependent models. Recently, Peter Abrams and Lev Ginzburg reviewed the controversial issue of what kind of function better describes the rate of prey consumption by an average predator, the so-called ''predator functional response.'' Here, we focus on reaction-diffusion predator– prey models with and without predator dependence in the functional response. We show that classical prey-dependent models cannot give rise to spatial structures through diffusiondriven instabilities; however, predator-dependent models with the same degree of complexity can. The origin of predator dependence in the rate of prey consumption is the mutual interference between predators. Therefore, we show that this mechanism can generate patchiness in a homogeneous environment under certain conditions of trophic interaction and predator–prey relative diffusion ; This work has been supported by CIRIT grants 1999FI 00524 UPC APMARN to D. Alonso and 1997FI 00296 UB APMARN to F. Bartumeus from the Catalan autonomous government. ; Peer reviewed

Trabajo presentado en la IEEE International Conference on Robotics and Automation (ICRA), conferencia virtual celebrada del 31 de mayo al 31 de agosto de 2020 ; Human-robot interaction is one of the keys of assistive robots. Robots are expected to be compliant with people but at the same time correctly perform the tasks. In such applications, Cartesian impedance control is preferred over joint control, as the desired interaction and environmental feedback can be described more naturally, and the force to be exerted by the robot can be readily adjusted. This paper addresses the problem of controlling a robot arm in the operational space with variable stiffness so as to continuously adapt the force exerted in each phase of motion according to the precision requirements. Moreover, performing dimensionality reduction we can separate the degrees of freedom (DoF) relevant for the task from the redundant ones. The stiffness of the former can be adjusted constantly to achieve the required accuracy, while task-redundant DoF can be used to achieve other goals such as avoiding obstacles by moving in the directions where accuracy is not critical. The designed method is tested teaching the robot to give water to drink to a model of human head. Our empirical results demonstrate that the robot can learn precision requirements from demonstration. Furthermore, dimensionality reduction is proved to be useful to avoid obstacles. ; This work was partially developed in the context of the project CLOTHILDE ("CLOTH manIpulation Learning from DEmonstrations"), which has received funding from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation programme (Advanced Grant agreement No 741930). This work is also supported by the Spanish State Research Agency through the María de Maeztu Seal of Excellence to IRI MdM-IP-2018-05. ; Peer reviewed

La investigación del Paleolítico superior en el interior peninsular se ha ido intensificando en los últimos años, aunque es un proceso lento. A los yacimientos ya conocidos, como Estebanvela, Buendía o Verdelpino se han ido uniendo nuevos descubrimientos, contribuyendo a apartar definitivamente el panorama de un aparente despoblamiento, algo que ya no es posible mantener al menos a partir del UMG. En este trabajo presentamos el reciente hallazgo y excavación de un yacimiento magdaleniense en Segovia, en el pie de monte sur del Sistema Central. Se trata de un hallazgo de relevancia, que contribuye a plantear nuevas vías de investigación sobre el poblamiento a finales del Paleolítico superior en las zonas interiores de la península, y sus relaciones con el Cantábrico y la zona levantina.

Este artículo contiene 22 páginas, 11 figuras. ; Research on hypercycles focuses on cooperative interactions among replicating species, including the emergence of catalytic parasites and catalytic shortcircuits. Further interactions may be expected to arise in cooperative systems. For instance, molecular replicators are subject to mutational processes and ecological species to behavioural shifts due to environmental and ecological changes. Such changes could involve switches from cooperative to antagonistic interactions, in what we call a functional shift. In this article, we investigate a model for a two-member hypercycle model, considering that one species performs a functional shift. First, we introduce the model dynamics without functional shifts to illustrate the dynamics only considering obligate and facultative cooperation. Then, two more cases maintaining cross-catalysis are considered: (i) a model describing the dynamics of ribozymes where a fraction of the population of one replicator degrades the other molecular species while the other fraction still receives catalytic aid; and (ii) a system in which a given fraction of the population predates on the cooperating species while the rest of the population still receives aid. We have characterised the key bifurcation parameters determining extinction, survival, and coexistence of species. We show that predation, regardless of the fraction that benefits from it, does not significantly change dynamics with respect to the degradative case (i), thus conserving dynamics and bifurcations. Their biological significance is interpreted, and their potential implications for the dynamics of early replicators and ecological species are outlined ; E.F. has been funded by the Spanish Government grant PID2019-104851GB-I00 (MICINN/FEDER, UE) and the Catalan Government grant 2017-SGR-1374. D.O. was funded by the Spanish Government grant CGL2017-85210-P (MICIN/FEDER, UE). D.A. has been partially funded by the Spanish "Minis terio de Ciencia, Innovación y Universidades" under the project CRISIS (PGC2018-096577-B-I00) and the European Regional Development Fund. J.S. has been partially funded by the CERCA Programme of the "Generalitat de Catalunya", by "Agencia Estatal de Investigacíon" grant RTI2018-098322-B-I00, and the "Ramón y Cajal" contract RYC-2017-22243. ; Peer reviewed

The authors are grateful for financial assistance for this work provided by the Spanish Government (Grants PGC2018-097965-B-I00 and MINECO-18-ECO2017-85788-R).

22 páginas, 4 tablas, 4 figuras ; Species abundance distributions (SAD) are probably ecology's most well-known empirical pattern, and over the last decades many models have been proposed to explain their shape. There is no concensus over which model is correct, because the degree to which different processes can be discerned from SAD patterns has not yet been rigorously quantified. We present a power calculation to quantify our ability to detect deviations from neutrality using species abundance data. We study non-neutral stochastic community models, and show that the presence of non-neutral processes is detectable if sample size is large enough and/or the amplitude of the effect is strong enough. Our framework can be used for any candidate community model that can be simulated on a computer, and determines both the sampling effort required to distinguish between alternative processes, and a range for the strength of non-neutral processes in communities whose patterns are statistically consistent with neutral theory. We find that even data sets of the scale of the 50 Ha forest plot on Barro Colorado Island, Panama, are unlikely to be large enough to detect deviations from neutrality caused by competitive interactions alone, though the presence of multiple non-neutral processes with contrasting effects on abundance distributions may be detectable. ; OAH, DA, and SJC were supported by the National Environment Research Council (grant no. NE/H007458/1). DA is supported by grant CGL2012- 39964 and Ramon y Cajal program from the Spanish Government. RSE thanks the Netherlands Organisation for Scientific Research (NWO) for funding through VIDI and VICI grants. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. ; Peer reviewed

The present work reports the distribution of pollutants in the Madrid city and province from 22 monitoring stations during 2010 to 2017. Statistical tools were used to interpret and model air pollution data. The data include the annual average concentrations of nitrogen oxides, ozone, and particulate matter (PM10), collected in Madrid and its suburbs, which is one of the largest metropolitan places in Europe, and its air quality has not been studied sufficiently. A mapping of the distribution of these pollutants was done, in order to reveal the relationship between them and also with the demography of the region. The multivariate analysis employing correlation analysis, principal component analysis (PCA), and cluster analysis (CA) resulted in establishing a correlation between different pollutants. The results obtained allowed classification of different monitoring stations on the basis of each of the four pollutants, revealing information about their sources and mechanisms, visualizing their spatial distribution, and monitoring their levels according to the average annual limits established in the legislation. The elaboration of contour maps by the geostatistical method, ordinary kriging, also supported the interpretation derived from the multivariate analysis demonstrating the levels of NO2 exceeding the annual limit in the centre, south, and east of the Madrid province.

This work was supported by Ministerio de Economía y Competitividad (Spain) through the I+D+i project referenced MINECO-17-CTQ2016-77887-C2-1-R and the Government of Principado de Asturias and the European Regional Development Fund through the project referenced FC-GRUPIN-IDI/2018/000186

© 2015 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works. ; In this paper, we provide an overview of the MANGO project and its goal. The MANGO project aims at addressing power, performance and predictability (the PPP space) in future High-Performance Computing systems. It starts from the fundamental intuition that effective techniques for all three goals ultimately rely on customization to adapt the computing resources to reach the desired Quality of Service (QoS). From this starting point, MANGO will explore different but interrelated mechanisms at various architectural levels, as well as at the level of the system software. In particular, to explore a new positioning across the PPP space, MANGO will investigate system-wide, holistic, proactive thermal and power management aimed at extreme-scale energy efficiency. ; The MANGO project starts in October 2015 and is funded by the European Commission under the Horizon 2020 FET-HPC program. This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No 671668. ; Flich Cardo, J.; Agosta, G.; Ampletzer, P.; Atienza Alonso, D.; Cilardo, A.; Fornaciari, W.; Kovac, M. (2015). The MANGO FET-HPC Project: an overview. IEEE Computer Society. https://doi.org/10.1109/CSE.2015.57 ; S

We evaluate the application of 57Fe Mössbauer spectroscopy to the determination of the composition of magnetite (Fe3O4)/maghemite (?-Fe2O3) mixtures and the stoichiometry of magnetite-maghemite solid solutions. In particular, we consider a recently proposed model-independent method which does not rely on a priori assumptions regarding the nature of the sample, other than that it is free of other Fe-containing phases. In it a single parameter, ?RT-the 'centre of gravity', or area weighted mean isomer shift at room temperature, T = 295 ± 5 K - is extracted by curve-fitting a sample's Mössbauer spectrum, and is correlated to the sample's composition or stoichiometry. We present data on high-purity magnetite and maghemite powders, and mixtures thereof, as well as comparison literature data from nanoparticulate mixtures and solid solutions, to show that a linear correlation exists between ?RT and the numerical proportion of Fe atoms in the magnetite environment: ? = Femagnetite/Fetotal = (?RT - ?o)/m, where ?o= 0.3206 ± 0.0022 mm s-1 and m = 0.2135 ± 0.0076 mm s-1. We also present equations to relate ? to the weight percentage w of magnetite in mixed phases, and the magnetite stoichiometry x = Fe2+/Fe3+ in solid solutions. The analytical method is generally applicable, but is most accurate when the absorption profiles are sharp; in some samples this may require spectra to be recorded at reduced temperatures. We consider such cases and provide equations to relate ?(T) to the corresponding ? value. ; This work was supported by the European Union Seventh Framework Programme through the NanoMag project 'Nanometrology standardisation methods for magnetic nanoparticles', under grant agreement no. 604448

Amorphous soft magnetic microwires have attracted much attention in the area of sensor applications due to their excellent properties. In this work, we study the influence of annealing treatments (stress and conventional) in the giant magnetoimpedance (GMI) response and the field sensitivity of the soft magnetic Co69.2Fe3.6Ni1B12.5Si11Mo1.5C1.2 glass-coated microwires. Here we report a remarkable and simultaneous enhancement of GMI effect and field sensitivity. The highest sensitivity of 104%/Oe and the GMI response of 234% were achieved for 300 °C stress-annealed samples at 472 and 236 MPa, respectively. Additionally, we found that stress-annealed microwires exhibit a frequency dependence on maximal GMI response and field sensitivity. These findings are obtained by fine-tuning their magnetoeslastic anisotropies through stress-annealing treatments of as-prepared microwires at the proper temperature and axial applied stress upon annealing. We hope that the results presented here widen the scope of investigations for the future design of soft magnetic materials for sensor purposes. ; D.G.-A is founded by MAT2017-83631-C3-R. This work was also supported by Spanish MCIU under PGC2018-099530-B-C31 (MCIU/AEI/FEDER, UE) and by the Government of the Basque Country under PIBA 2018-44 project and by the University of Basque Country under the scheme of "Ayuda a Grupos Consolidados" (Ref.: GIU18/192).

The authors thank Thierry Peyrard, Dominique Gien, Sirandou Tounkara, and Eliane Véra at Centre National de Référence pour les Groupes Sanguins for the management of blood samples. The authors thank Sandrine Genetet and Isabelle Mouro-Chanteloup at the Inserm UMR_S1134 unit for their assistance in experiments. The authors also thank Michaël Dussiot at the Institute Imagine for his assistance in imaging flow cytometry. We thank Johanna Bruce and Virginie Salnot at 3P5 Proteomics Platform for sample preparation and analysis, and François Guillonneau and Patrick Mayeux for their management and strategies. Funding: The work was supported by Institut National de la Santé et de la Recherche Médicale (Inserm); Institut National de la Transfusion Sanguine (INTS); the University of Paris; and grants from Laboratory of Excellence (Labex) GR-Ex, reference No. ANR-11-LABX-0051. The Labex GR- Ex is funded by the IdEx program "Investissements d'avenir" of the French National Research Agency, reference No. ANR-11-IDEX-0005-02 and ANR-18-IDEX-0001. R.B., M.G.R., and D.M.A. were funded by the European Union's Horizon 2020 Research and Innovation Program under grant agreement No. 675115-RELEVANCE-H2020-MSCA-ITN-2015. R.B. also received financial support from Société Française d'Hématologie (SFH) and Club du Globule Rouge et du Fer (CGRF). R.B. is currently funded by the Innovate UK Research and Innovation Knowledge Transfer Partnership (KTP) between University of Aberdeen and Vertebrate Antibodies Ltd. (Partnership No. KTP12327). T.D. was supported by PhD grants from Université Paris Saclay MESR (Ministère Enseignement Supérieur et de la Recherche) and then FRM (Fondation recherche médicale). The Orbitrap Fusion mass spectrometer was acquired with funds from Fonds Europeen de Developpement Regional (FEDER) through the Operational Program for Competitiveness Factors and Employment 2007-2013 and from the Canceropole Ile de France. ; Peer reviewed ; Publisher PDF

In this paper, we provide an overview of the MANGO project and its goal. The MANGO project aims at addressing power, performance and predictability (the PPP space) in future High-Performance Computing systems. It starts from the fundamental intuition that effective techniques for all three goals ultimately rely on customization to adapt the computing resources to reach the desired Quality of Service (QoS). From this starting point, MANGO will explore different but interrelated mechanisms at various architectural levels, as well as at the level of the system software. In particular, to explore a new positioning across the PPP space, MANGO will investigate system-wide, holistic, proactive thermal and power management aimed at extreme-scale energy efficiency. ; This project has received funding from the the European Union's Horizon 2020 research and innovation programme under grant agreement No 671668. ; Flich Cardo, J.; Agosta, G.; Ampletzer, P.; Atienza Alonso, D.; Brandolese, C.; Cilardo, A.; Fornaciari, W. (2016). Enabling HPC for QoS-sensitive applications: the MANGO approach. http://hdl.handle.net/10251/62629 ; S