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Mesoporous Ni and Cu-Ni (Cu20Ni80 and Cu45Ni55 in at. %) films, showing a three-dimensional (3D) porous structure and tunable magnetic properties, are prepared by electrodeposition from aqueous surfactant solutions using micelles of P-123 triblock copolymer as structure-directing entities. Pores between 5 and 30 nm and dissimilar space arrangements (continuous interconnected networks, circular pores, corrugated mesophases) are obtained depending on the synthetic conditions. X-ray diffraction studies reveal that the Cu-Ni films have crystallized in the face-centered cubic structure, are textured, and exhibit certain degree of phase separation, particularly those with a higher Cu content. Atomic layer deposition (ALD) is used to conformally coat the mesopores of Cu20Ni80 film with amorphous Al2O3, rendering multiphase "nano-in-meso" metal-ceramic composites without compromising the ferromagnetic response of the metallic scaffold. From a technological viewpoint, these 3D nanoengineered composite films could be appealing for applications like magnetically actuated micro/nanoelectromechanical systems (MEMS/NEMS), voltage-driven magneto-electric devices, capacitors, or as protective coatings with superior strength and tribological performance. ; Financial support by the European Research Council (SPIN-PORICS 2014-Consolidator Grant, Agreement No 648454), the Spanish Government (Project MAT2017-86357-C3-1-R and associated FEDER) and the "Severo Ochoa" Programme for Centres of Excellence in R&D (SEV-2015-0496), the Generalitat de Catalunya (2017-SGR-292 and 2017-SGR-1519) and the European Union's Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement no 665919 is acknowledged. E.P. and M. C. are grateful to MINECO for the "Ramón y Cajal" contract (RYC-2012-10839 and RYC-2013-12448). ; Peer reviewed

Melatonin (Mel) is considered a potent natural antioxidant molecule given its free-radical scavenging ability. Its origin is traced back to the origin of aerobic life as early defense against oxidative stress and radiation. More complex signaling functions have been attributed to Mel as a result of evolution in different biological kingdoms, which comprise gene expression modulation, enzyme activity, and mitochondrial homeostasis regulation processes, among others. Since Mel production has been recently reported in wine yeast, we tested the protective effect of Mel on Saccharomyces cerevisiae against oxidative stress and UV light. As the optimal conditions for S. cerevisiae to synthesize Mel are still unknown, we developed an intracellular Mel-charging method to test its effect against stresses. To assess Mel's ability to protect S. cerevisiae from both stresses, we ran growth tests in liquid media and viability assays by colony count after Mel treatment, followed by stress. We also analyzed gene expression by qPCR on a selection of genes involved in stress protection in response to Mel treatment under oxidative stress and UV radiation. The viability in the Mel-treated cells after H2O2 stress was up to 35% greater than for the untreated controls, while stress amelioration reached 40% for UVC light (254 nm). Mel-treated cells showed a significant shortened lag phase compared to the control cells under the stress and normal growth conditions. The gene expression analysis showed that Mel significantly modulated gene expression in the unstressed cells in the exponential growth phase, and also during various stress treatments. ; This work has been funded from the Spanish Government through MINECO and FEDER (AGL2016-77505-C3-1-R and PCIN-2015-143 grants) and from Generalitat Valenciana through PROMETEOII/2014/042 grant, awarded to JG. ; Peer reviewed

Hinging on ideas from physical-layer network coding, some promising proposals of coded random access systems seek to improve system performance (while preserving low complexity) by means of packet repetitions and decoding of linear combinations of colliding packets, whenever the decoding of individual packets fails. The resulting linear combinations are then temporarily stored in the hope of gathering enough linearly independent combinations so as to eventually recover all individual packets through the resolution of a linear system at the end of the contention frame. However, it is unclear which among the numerous linear combinations-whose number grows exponentially with the degree of collision-will have low probability of decoding error. Since no analytical framework exists to determine which combinations are easiest to decode, this makes the case for a machine learning algorithm to assist the receiver in deciding which linear combinations to target. For this purpose, we train neural networks that approximate the error probability for every possible linear combination based on the estimated channel gains and demonstrate the effectiveness of our approach by numerical simulations. ; Grant numbers : This work was supported by the Catalan Government under grant 2017 SGR 1479 and by the Spanish Ministery of Economy and Competitiveness through projects TEC2014-59255-C3-1-R (ELISA) and TEC2015-69868-C2- 2-R (ADVENTURE).© 2018 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.

Transcurridos más de cuarenta años desde el final de la dictadura franquista, una parte del imaginario colectivo español la identifica como la primera gran impulsora del Estado de Bienestar en España. Dislocados por la historiografía los viejos, pero eficaces, mitos que sirvieron para justificar el origen de la rebelión militar y el hambre, y también el que pretendía redimir a la dictadura por el desarrollo económico posterior, todavía permanece en pie el de la dictadura como creadora de un sistema de seguridad social en España que anticipa el actual. Las investigaciones existentes sobre las políticas sociales de la dictadura, realizadas por historiadores de la medicina o de la economía, demuestran sin embargo lo exagerado de este tipo de percepciones, y revelan una realidad más compleja que requiere un debate en profundidad al que este trabajo pretende contribuir. ; More than four decades since the end of Franco's dictatorship, part of the Spanish collective memory identifies the dictatorship as the first great promoter of the Welfare State in Spain. Historiographical research has dismantled the old, though effective, myths used to justify the origin of the military rebellion and the famine, as well as the myth intended to redeem the dictatorship based on the subsequent economic modernization. However, the myth of Franco's dictatorship as creator of the social welfare system in Spain that anticipated the current one remains. Many investigations conducted by historians of medicine and economics on Franco's dictatorship social policies demonstrate the exaggeration of this type of perceptions. They also reveal a more complex reality and the need for in-depth discussion to which this paper is intended to contribute. ; Proyecto de investigación HAR2017-83744-C3-1-P (MINECO).

This paper deals with the problem of sparse beamforming for interference mitigation in milimiter wave (mm Wave) frequency bands. Multiantenna solutions in mmWave are generally implemented with phase shifters which are known to have good interference rejection capabilities. However, phase shifters are power-demanding components and, depending on their resolution, they require bulky hardware solutions able to accommodate the control lines. On the other hand, the use of switches leads to a cost-efficient alternative able to provide a sufficiently large interference rejection while substantially reducing the hardware cost and power consumption. This work proposes a beamforming scheme able to maximize the signal-to-interference-plus-noise ratio (SINR) assuming that the beamforming weights can only take 0 and 1 values. The resulting optimization problem is a binary quadratic fractional problem which is a difficult non-convex problem. Two optimization approaches are proposed; namely, the semidefinite relaxation and the penalized convex-concave procedure. We show that both techniques behave well in the considered scenarios and their performance is close to the optimization problem upper bound value. ; Grant numbers : This work has received funding from the Spanish Ministry of Economy and Competitiveness (Ministerio de Economia y Competitividad) under project TEC2014-59255-C3-1-R (ELISA) and from the Catalan Government (2017-SGR-1479 and 2014-SGR-1551).© 2018 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.

Magnetotactic bacteria synthesize a chain of magnetic nanoparticles, called magnetosome chain, used to align and swim along the geomagnetic field lines. In particular, Magnetospirillum gryphiswaldense biomineralize magnetite, Fe3O4. Growing this species in a Co-supplemented medium, Co-doped magnetite is obtained, tailoring in this way the magnetic properties of the magnetosome chain. Combining structural and magnetic techniques such as transmission electron microscopy, energy-dispersive x-ray spectroscopy, X-ray absorption near edge structure, and X-ray magnetic circular dichroism, we determine that 1% of Co2+ substitutes Fe2+ located in octahedral places in the magnetite, thus increasing the coercive field. In the framework of the Stoner-Wohlfarth model, we have analyzed the evolution of the hysteresis loops as a function of temperature determining the different magnetic anisotropy contributions and their evolution with temperature. In contrast with the control magnetosome chains, whose effective anisotropy is uniaxial in the whole temperature range from 300 to 5 K, the effective anisotropy of Codoped magnetosome chains changes appreciably with temperature, from uniaxial down to 150 K, through biaxial down to 100 K, to triaxial below 100 K. ; L.M. acknowledges the Basque Government for her fellowship (PRE_2015_1_0130). We acknowledge the technical and human support provided by SGIker (UPV/EHU). Funding from the Spanish Government (project nos. MAT2014-55049-C2-R and MAT2017-83631-C3-R) and Basque Government (project n. IT711-13) is acknowledged. We thank the ESRF (CRG BM25 beamline-SpLine) and HZB for the allocation of synchrotron radiation beamtime and funding under the project CALIPSOplus (Grant Agreement 730872) from the EU Framework Programme for Research and Innovation HORIZON 2020. We thank R. Fernández-Pacheco for his assistance in the EDS measurements.

El espacio urbano sirvió en el Antiguo Régimen como un ?escenario? en el que se expresaban posiciones y tensiones de naturaleza social, económica y política. El análisis de las ocupaciones, desalojos y traslados que experimentó el tribunal de la Inquisición de Sicilia hasta ocupar su emplazamiento definitivo en la ciudad de Palermo, con los agentes y objetivos que los impulsaron y los conflictos y negociaciones que se escenificaron en torno a ellos, se plantea en este trabajo como vía de aproximación a las dinámicas sobre las que se configuró la posición del Tribunal en términos de competencia-cooperación, conflicto-negociación, subordinación y preeminencia, en el espacio político, institucional y jurisdiccional de la ciudad y del reino sicilianos y también de la Monarquía española a lo largo del siglo XVI. ; This article analyses the process of stabilizing the seat of the Spanish Inquisition of Sicily in the city of Palermo. If we consider urban space in the Old Regime as a "scenario" for social, economic and political expressions, the study of the objectives, tensions and negotiations that were staged around the occupations, evictions and transfers experienced by the seat of the Inquisitorial Court in Palermo, allows to specify the dynamics, in terms of competition-cooperation, conflict-negotiation, subordination and pre-eminence, on which the position of the Inquisitorial Court was configured in the jurisdictional, political, institutional and social space of the city, the Kingdom of Sicily and the Spanish Monarchy in the 16th century. ; Este trabajo se ha realizado en el marco del Proyecto de Investigación MINECO/FEDER, UE, Culturas urbanas en la España moderna: policía, gobernanza e imaginarios (siglos XVI-XIX), HAR2015-64014-C3-1-R.

Fuzzy logic systems are useful for solving problems in many application fields. However, these systems are usually stored in specific formats and researchers need to rewrite them to use in new problems. Recently, the IEEE Computational Intelligence Society has sponsored the publication of the IEEE Standard 1855-2016 to provide a unified and well-defined representation of fuzzy systems for problems of classification, regression, and control. The main aim of this standard is to facilitate the exchange of fuzzy systems across different programming systems in order to avoid the need to rewrite available pieces of code or to develop new software tools to replicate functionalities that are already provided by other software. In order to make the standard operative and useful for the research community, this paper presents JFML, an open source Java library that offers a complete implementation of the new IEEE standard and capability to import/export fuzzy systems in accordance with other standards and software. Moreover, the new library has associated a Website with complementary material, documentation, and examples in order to facilitate its use. In this paper, we present three case studies that illustrate the potential of JFML and the advantages of exchanging fuzzy systems among available software ; This work was supported in part by the XXII Own Research Program (2017) of the University of Córdoba, in part by the Spanish Ministry of Economy and Competitiveness under Grants RYC-2016-19802 (Ramón y Cajal contract), TIN2017-84796-C2-1-R, TIN2014-56633-C3-3-R, TIN2014-57251-P, and TIN2015-68454-R, in part by the Andalusian Government under Grant P11-TIC-7765, in part by the Xunta de Galicia (accreditation 2016-2019), and in part by the European Union (European Regional Development Fund).

Enhanced light-matter interactions are the basis of surface-enhanced infrared absorption (SEIRA) spectroscopy, and conventionally rely on plasmonic materials and their capability to focus light to nanoscale spot sizes. Phonon polariton nanoresonators made of polar crystals could represent an interesting alternative, since they exhibit large quality factors, which go far beyond those of their plasmonic counterparts. The recent emergence of van der Waals crystals enables the fabrication of high-quality nanophotonic resonators based on phonon polaritons, as reported for the prototypical infrared-phononic material hexagonal boron nitride (h-BN). In this work we use, for the first time, phonon-polariton-resonant h-BN ribbons for SEIRA spectroscopy of small amounts of organic molecules in Fourier transform infrared spectroscopy. Strikingly, the interaction between phonon polaritons and molecular vibrations reaches experimentally the onset of the strong coupling regime, while numerical simulations predict that vibrational strong coupling can be fully achieved. Phonon polariton nanoresonators thus could become a viable platform for sensing, local control of chemical reactivity and infrared quantum cavity optics experiments. ; We also acknowledge support from the European Commission under the Graphene Flagship (GrapheneCore1, Grant no. 696656), the Marie SklodowskaCurie individual fellowship (SGPCM-705960), the Spanish Ministry of Economy and Competitiveness (Maria de Maetzu Units of Excellence Programme MDM-2016-0618 and national projects FIS2014-60195-JIN, MAT2014-53432- C5-4-R, MAT2015-65525-R, MAT2015-65159-R, FIS2016-80174-P, MAT2017- 88358-C3-3-R), the Basque government (PhD fellowship PRE-2016-1-0150, PRE-2016-2-0025), the Department of Industry of the Basque Government (ELKARTEK project MICRO4FA), the Regional Council of Gipuzkoa (project no. 100/16) and the ERC starting grant 715496, 2DNANOPTICA. ; Peer Reviewed

MOOCs (Massive Open Online Courses) have changed the way in which OER (Open Educational Resources) are bundled by teachers and consumed by learners. MOOCs represent an evolution towards the production and offering of structured quality OER. Many institutions that were initially reluctant to providing OER have, however, joined the MOOC wave. Nevertheless, MOOCs detractors strongly criticize their high dropout rates. The dropout rate is a commonly accepted metric of success for traditional education, but it may not be as suitable when dealing with OER, in general, and with MOOCs, in particular, since learners' motivations to take a course are very diverse, and certain self -regulated learning strategies are required to tackle the lack of personalized tutoring and keep pace in the course . This paper presents an empirical study on the motivation and learning strategies of MOOC learners. Six thousand three hundred and thirty-five learners from 160 countries answered a self report 7- point Likert-type questionnaire based on the Motivated Strategies for Learning Questionnaire (MSLQ) as part of a MOOC titled Introduction to Programming with Java. Results indicate that learners were highly motivated and confident to do well in the course. Learning strategies, however, can be improved, especially regarding time management. ; This work has been co-funded by the Erasmus+ Programme of the European Union, projects MOOC-Maker (561533-EPP-1-2015-1-ES-EPPKA2-CBHE-JP), SHEILA (562080-EPP-1-2015-BE-EPPKA3-PI-FORWARD) and COMPETEN-SEA (574212-EPP-1-2016-1- NL-EPPKA2-CBHE-JP), by the Madrid Regional Government, through the eMadrid Excellence Network (S2013/ICE-2715), and by the Spanish Ministry of Economy and Competitiveness, project RESET (TIN2014-53199-C3-1-R) and fellowships FPDI-2013-17411 and PTQ-15-07505.

The irradiation of gold nanorod colloids with a femtosecond laser can be tuned to induce controlled nanorod reshaping, yielding colloids with exceptionally narrow localized surface plasmon resonance bands. The process relies on a regime characterized by a gentle multishot reduction of the aspect ratio, whereas the rod shape and volume are barely affected. Successful reshaping can only occur within a narrow window of the heat dissipation rate: Low cooling rates lead to drastic morphological changes, and fast cooling has nearly no effect. Hence, a delicate balance must be achieved between irradiation fluence and surface density of the surfactant on the nanorods. This perfection process is appealing because it provides a simple, fast, reproducible, and scalable route toward gold nanorods with an optical response of exceptional quality, near the theoretical limit. ; This work was funded by the Spanish MINECO (Ministry of Economy and Competitiveness; grants CTQ2012-37404-C02-01, MAT2013-46101-R, MAT2014-59678-R, ENE2015-70300-C3-3-R, and CTQ2015-65033-P), the EUROfusion Consortium (AWP15-ENR-01/CEA-02), the Madrid Regional Government (S2013/MIT-2775 and S2013/MIT-2807), and the European Research Council (ERC Advanced Grant 267867, Plasmaquo). A.G.-M. and G.G.-R. respectively acknowledge receipt of Ramón y Cajal and FPI (Formación de Personal Investigador) fellowships from the Spanish MINECO. P.D.-N. acknowledges receipt of a fellowship from the Madrid Regional Government. The authors acknowledge the computer resources and technical assistance provided by CESVIMA (Centro de Supercomputación y Visualización de Madrid, Universidad Politécnica de Madrid) and the facilities provided by the Center for Ultrafast Lasers and the National Center of Microscopy (Universidad Complutense de Madrid). All results are reported in the main paper and supplementary materials.

Cloud Modulation (CM) is a novel transmission method that mitigates the non-linear impairments introduced by the Radio-over-Fiber (RoF) links of a distributed antenna system. In CM, constant-envelope phase-modulated radio symbols are transmitted over the fiber fronthaul to mitigate the non-linear distortion originated by the opto-electrical interfaces, optical fibers, and RF power amplifiers. In contrast to contemporary distributed antenna systems, where the amplitude modulation of the radio signal is already present at the input of the RoF link, the amplitude modulation of received CM symbols is achieved over-the-air by selecting the remote antenna unit that should be active at each time symbol. The propagation characteristics of the wireless channel, whose diffuse nature is typically represented with the cloud metaphor, creates the desired amplitude modulation and motivates the name of the proposed transmission method. The guidelines to design CM alphabets for different hybrid fiber-wireless scenarios are presented. Notable performance gains are observed when CM is compared to a joint transmission coordinated multi-point scheme in presence of similar levels of non-linear distortion in the RoF fronthaul. ; Grant numbers : This work has received funding from the Spanish Government under Project ELISA (TEC2014-59255-C3-1-R) and the Catalan Government under Grant 2014SGR1567.© 2017 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.

Offset-QAM-based filterbank multicarrier (FBMC-OQAM) has been shown to be a promising alternative to cyclic prefix-orthogonal frequency division multiplexing for the future generation of wireless communication systems. Unfortunately, as the channel gets more selective in time and frequency, the FBMC-OQAM orthogonality is progressively destroyed and distortion appears after the demodulation process at the receiver. While channel frequency selectivity has been very widely studied in the FBMC literature, the impact of time selectivity of the channel has not received that much attention. In this paper, the effect of the two types of selectivity on a multiple-input multiple-output (MIMO) FBMC system is characterized and a parallel equalization structure that can compensate for the doubly dispersive nature of the channel is proposed. This design uses multiple analysis filterbanks and extends previous approaches that were dealing only with channel frequency selectivity. A theoretical approximation of the remaining distortion after equalization is given. The study is performed for a general MIMO system but can also be particularized to single-input single-output systems. Simulation results demonstrate the high efficiency of the proposed receiver structure and the accuracy of the theoretical approximations is verified. ; Grant numbers : The research reported herein was partly funded by the Catalan and Spanish governments under grants 2014SGR1567 and ELISA (TEC2014-59255-C3-1).© 2017 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.

Terahertz (THz) band communication has abundant spectral resources to accommodate multiple broadband carriers. However, the strong path loss attenuation and the limited transmission power affect the maximum number of carriers that can be activated. A simple way to address this limitation consists in transmitting the same message from multiple transmission points, using Joint-Transmission (JT) Coordinated Multi-Point (CoMP). However, the distance-frequency-dependent molecular absorption that THz channels experience makes the implementation of JTCoMP challenging. In this paper, we propose a decentralized scheme that takes into account the effect of distance to select the per-carrier transmit beamforming weights and powers. For this purpose, low-rate feedback information is reported from the receiver to the transmission points, such that decisions performed locally take into account the ones made in the coordinated set. Notable sum data rate gains are observed when compared to the baseline schemes, where transmission power is equally divided among carriers or independently allocated using waterfilling. As expected, the accuracy of the reported channel phase information, the number active transmission points, and the distance-dependent frequency selectivity of the THz channel affect the sum data rate that multi-carrier JT-CoMP can provide ; Grant numbers : This work has received funding from the Spanish Government under Projects ELISA (TEC2014-59255-C3-1-R) and the Catalan Government under Grant 2014SGR1567.© 2017 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.

[EN] The thermal transformation of hydrothermally prepared Cs-Nb-W-O mixed oxides has been studied in the 25-1000 degrees C temperature range. Structural evolution of the prepared solids was monitored by in situ synchrotron X-ray diffraction, absorption spectroscopy techniques, conventional powder X-ray diffraction, thermogravimetric analysis, infrared and Raman spectroscopy, and high resolution transmission electron microscopy (HRTEM and STEM). The as-grown solids show the hexagonal tungsten bronze (HTB) structure, which can be stabilized above 900 degrees C depending on the chemical composition. From this temperature, solids are selectively transformed into the orthorhombic Cs-0.5(Nb2.5W2.5)O-14 structure-type. The same results are obtained for Cs-0.5(Nb2.5W2.5-xMx)O-3, with M = V or Mo (x = 0-1.25). A mechanism for the quantitative transformation at high temperature is proposed in terms of the relative occupancy of the hexagonal channels in the HTB-type phase as well as the Nb/(W + V) ratio. ; M.D.S. and J.M.L.N. acknowledge the Spanish Government-MINECO projects (CTQ2015-68951-C3-1-R and SEV-2016-0683). E.G.G. acknowledges the financial support through Projects MAT2013-46452-C4 and MAT2016-78362-C4-4-R and the valuable help of Dr. Urones-Garrote in STEM performing. Authors thank the ICTS Centro Nacional de Microscopia Electronica (UCM) for instrumental facilities and LNLS/CNPEM-Brazil for the synchrotron radiation facilities. ; Soriano Rodríguez, MD.; Garcia-Gonzalez, E.; Concepción Heydorn, P.; Rodella, C.; López Nieto, JM. (2017). The Self-Organized Transformation from Hexagonal to Orthorhombic Bronze of Cs-Nb-W-O Mixed Oxides Prepared Hydrothermally. Crystal Growth & Design. 17(12):6320-6331. https://doi.org/10.1021/acs.cgd.7b00999 ; S ; 6320 ; 6331 ; 17 ; 12