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Key message. No temporal change was recorded during summer in fuel availability in Pinus pinaster stands, contrary to predictions from the Forest Fire Weather Index. Also, thinning had no mid-term effect on fuel moisture or canopy structure. Context. Forest fires are a major problem in Mediterranean countries. Management actions, such as fuel reductions, are one of the main tools to diminish fire risk, but the midterm efficacy of such tools remains largely untested with empirical data. Aims. Here, we test for midterm effects of thinning on fuel moisture and crown bulk density in P. pinaster stands and whether temporal variations in fuel moisture correlated with predictions from the Fire Weather Index, a commonly used index on fire risk, and its components. Methods. We compared fuel moisture over a fire season and crown bulk density in nine pairs of thinned/unthinned plots 7 years after treatments were applied. Results. We observed that fuel moisture remained stable during a fire season, as a likely result of drought-induced physiological adjustments, including stomatal regulation and others, which allow leaves to maintain a large humidity even during drought, and that thinning had no midterm effect on fuel moisture or crown bulk density. Moreover, the Fire Weather Index and its components displayed different temporal dynamics than those observed in fuel moisture. Conclusion. These results are important as they indicate that thinning may only have a limited, short-term impact towards diminishing the potential for crown fire spread in these stands and that current indices to evaluate fire risk may require a re-evaluation. ; This study is funded by the Spanish Government (RYC-2012-10970, AGL2015-69151-R, AGL2015-68274-C3-3-R).

Learners in massive open online courses (MOOCs) are required to be autonomous during their learning process, and thus they need to self-regulate their learning to achieve their goals. According to existing literature, self-regulated learning (SRL) research in MOOCs is still scarce. More studies which build on past works regarding SRL in MOOCs are required, as well as literature reviews that help to identify the main challenges and future research directions in relation to this area. In this paper, the authors present the results of a systematic literature review on SRL in MOOCs, covering all the related papers published until the end of 2017. The papers considered in this review include real experiences with at least a MOOC (other learning scenarios sometimes claimed as MOOCs, such as blended courses, or online courses with access restrictions, are out of the scope of this analysis). Most studies on SRL in MOOCs share some common features: they are generally exploratory, based on one single MOOC and tend not to specify in which SRL model they are grounded. The results reveal that high self-regulators engage in non-linear navigation and approach MOOCs as an informal learning opportunity. In general, they prefer setting specific goals based on knowledge development and control their learning through assignments. ; This work was supported by the CONICYT/DOCTORADO NACIONAL 2016 under Grant 21160081; European Commission under Grant 561533-EPP-1-2015-1-ES-EPPKA2-CBHE-JP and 574212-EPP-1-2016-1-NL-EPPKA2-CBHE-JP; Fondo Nacional de Desarrollo Científico y Tecnológico under Grant 11150231; Madrid Regional Government under Grant S2013/ICE-2715; Spanish Ministry of Economy and Competitiveness under Grant TIN2017-85179-C3-1-R. ; Publicado

This study received financial support from Research Project HAR2016-75788-P of Spanish Government. The authors are grateful to Prof. J.A. Quirós Castillo (University of Basque Country) for the animal bones from the San Martín de Lantarón site; to Richard Davies for assistance with the English version; to Profs. Rafael Martínez (University of Granada), and Marco Milella (University of Bern) for preparing Figs. 3 and 4, respectively. Many thanks also to the editor and the anonymous reviewers for their careful reading and suggestions. ; A medieval osteological sample (n = 20) from the isolated rural community of San Baudelio de Berlanga (Soria, N-Spain) was studied using paleopathological and stable isotope analyses. The necropolis was initially dated by archeologists between the XI and XII centuries AD and contains 57 individuals. The main objective of this study was to investigate the diet and the chronology of these individuals to improve the understanding not only of the diet but also of the population dynamics in an isolated rural site. The isotopic composition of their rib bone collagen was determined. δ15N values ranged between 9.3‰ and 11.5‰, with a mean of 10.3 + 0.5‰ (AIR), while δ13C values ranged between −17.6‰ and −19.0‰ with a mean of −18.2 + 0.4‰ (V-PDB). Radiocarbon results dated the individuals to between the XI and mid-XIII century. The stable isotopic results suggest a mixed terrestrial diet dominated by C3 cereals but including also animal products (e.g. meat and dairy products). Isotopic differences between sexes may be related more closely to social (patrilineal pattern of pairing) and biodemographical (lower female life expectancy) factors than dietary gender differences. ; Spanish Government HAR-2016-75788-P

The long-term hydroclimatic variability in Santiago (Chile) was analysed by means of a new 481-year (1536-2016 CE) tree-ring reconstruction of the Standardized Precipitation Evapotranspiration Index (SPEI) of August, integrating the hydroclimatic conditions during the preceding 14 months. Results show a high frequency of extreme drought events in the late 20th and early 21st centuries, while the frequency of extreme wet events was higher in the 17th-18th centuries. The mid-20th century represents a breaking point for the hydroclimatic history in the region, including some significant changes: (a) the interannual variability increased; (b) the wet events became less intense; (c) the extreme dry events became more frequent; and (d) the most intense dry event of the entire period was identified, coinciding with the so-called Megadrought (2006-2016). A correlation analysis between the reconstructed SPEI and three climate indices (PDO, SOI and Nino3.4) was performed at monthly scale, considering different multi-annual aggregations. The analysis shows diverse impacts on the hydroclimatic variability, with positive correlations between SPEI and PDO as well as Nino3.4, and negative correlations between SPEI and SOI. The most significant correlations were, overall, found at multi-annual time scales (>7 years). Results help to better understand the current hydroclimatic changes (Megadrought) in a long-term context. ; "Juan de la Cierva" postdoctoral grant FJCI-2017-31595 Spanish Government CAS/1900020 Fulbright Foundation CAS/1900020 Climatology Group (Catalan Government) 2017SGR1362 CLICES Project CGL2017-83866-C3-2-R Government of Aragon through the "Programme of research groups" H38 National Science Foundation (NSF) NSF - Office of the Director (OD) OISE-1743738 National Science Foundation (NSF) NSF - Directorate for Geosciences (GEO) AGS-1702439 CONICYT PIA of the Institute of Ecology and Biodiversity (IEB) AFB170008 CGL2015-69985-R

This work presents a 16-way Ku-band radial power combiner for high power and high frequency applications, using the very low loss TE01 circular waveguide mode. The accomplished design shows an excellent performance: the experimental prototype has a return loss better than 30 dB, with a balance for the amplitudes of ( 0.15 dB) and ( 2.5 ) for the phases, in a 16.7% fractional bandwidth (2 GHz centered at 12 GHz). For obtaining these outstanding specifications, required, for instance, in highfrequency amplification or on plasma systems, a rigorous step-by-step procedure is presented. First, a high-purity mode transducer has been designed, from the TE10 mode in the rectangular waveguide to the TE01 mode in the circularwaveguide, with very high attenuation (>50 dB) for the other propagating and evanescent modes in the circularwaveguide. This transducer has been manufactured and measured in a back-to-back configuration, validating the design process. Second, an E-plane 16-way radial power divider has been designed, where the power is coupled from the 16 non-reduced-height radial standardwaveguides into the TE01 circularwaveguide mode, improving the insertion loss response and removing the usual tapered transformers of previous designs limiting the power handling. Finally, both the transducer and the divider have been assembled to make the final radial combiner. The prototype has been carefully manufactured, showing very good agreement between the measurements and the full-wave simulations ; The authors would like to thank INMEPRE S.A., the diligence in the manufacturing process. This work was supported by the Spanish government under Grant (ADDMATE) No. TEC2016-76070-C3-1/2-R (AEI/FEDER/UE) and the program of Comunidad de Madrid S2013/ICE-3000 (SPADERADARCM)

We show that the magnetic ordering of coupled atomic dimers on a superconductor is revealed by their intragap spectral features. Chromium atoms on the superconductor β-Bi2Pd surface display Yu-Shiba-Rusinov bound states, detected as pairs of intragap excitations in tunneling spectra. By means of atomic manipulation with a scanning tunneling microscope's tip, we form Cr dimers with different arrangements and find that their intragap features appear either shifted or split with respect to single atoms. These spectral variations are associated with the magnetic coupling, ferromagnetic or antiferromagnetic, of the dimer, as confirmed by density functional theory simulations. The striking qualitative differences between the observed tunneling spectra prove that intragap Shiba states are extremely sensitive to the magnetic ordering on the atomic scale ; We thank Javier Zaldivar and Joeri de Bruijckere for developing the deconvolution process and Sebastian Bergeret for discussions. D.-J. C. and J. I. P. thank the European Union for support under the H2020-MSCA-IF-2014 Marie-Curie Individual Fellowship program (Proposal No. 654469), Spanish MINECO (MAT2016-78293-C6-1-R), Diputacion Foral de Gipuzkoa for Grant No. 64/15, and the European Regional Development Fund (ERDF). N. L. thanks Spanish MINECO (Grant No. MAT2015-66888-C3-2-R). M. M. U. acknowledges Spanish MINECO (MAT2014-60996-R). E. H., I. G., and H. S. acknowledge FIS2014-54498-R and MDM-2014-0377, COST MP16218 nanocohybri, ERC PNICTEYES Grant Agreement No. 679080, and Departamento Administrativo de Ciencia, Tecnología e Innovación, COLCIENCIAS (Colombia), Programa doctorados en el exterior and convocatoria 568-2012, as well as Comunidad de Madrid through program Nanofrontmag-CM (Grant No. S2013/MIT-2850)

Discrepancia entre la información que aparece en el artículo que indica que el copyright es de Elsevier, y la información que aparece en la página de la revista y en el Copyright Clearance Center que indican © 2019 The Authors. Published by Elsevier B.V., así como que el artículo está publicado en Open Access under a Creative Commons licence ; This work presents the design and experimental validation of a high performance, compact, waveguide duplexer operating from 91.5 to 96.5 GHz for its integration in diverse W-band microwave equipment as in plasma diagnosis applications. It uses a single frequency band, with two signals discriminated by different orthogonal circular polarization, which is generated by means of a septum orthomode transducer (OMT) polarizer. Moreover, this component is optimized loaded with the horn antenna for improving the overall system performance. It is explained how these two components are integrated into a very compact duplexer, designed using efficient numerical algorithms. The manufacturing process by mean of high precision milling, and including electrical discharge machining (EDM) has led to excellent performances. The measured return loss level and isolation are higher than 30 dB, and the insertion loss level is below 0.3 dB. Finally, the key parameter in this device, which reflects the symmetry in the manufacturing process, i.e., the axial ratio, is lower than 0.6 dB for both polarizations, an excellent result showing the potential of the presented design ; This work was supported by the Spanish government under grants (ADDMATE) TEC2016-76070-C3-1/2-R (Agencia Estatal de Investigación, Spain, Fondo Europeo de Desarrollo Regional: AEI/FEDER/UE) and the program of Comunidad de Madrid, Spain S2013/ICE-3000 (SPADERADARCM)

Atomically-sharp tips in close proximity of metal surfaces create plasmonic nanocavities supporting both radiative (bright) and non-radiative (dark) localized surface plasmon modes. Disentangling their respective contributions to the total density of optical states remains a challenge. Electroluminescence due to tunnelling through the tip-substrate gap could allow the identification of the radiative component, but this information is inherently convoluted with that of the electronic structure of the system. In this work, we present a fully experimental procedure to eliminate the electronic-structure factors from the scanning tunnelling microscope luminescence spectra by confronting them with spectroscopic information extracted from elastic current measurements. Comparison against electromagnetic calculations demonstrates that this procedure allows the characterization of the meV shifts experienced by the nanocavity plasmonic modes under atomic-scale gap size changes. Therefore, the method gives access to the frequency-dependent radiative Purcell enhancement that a microscopic light emitter would undergo when placed at such nanocavity ; We acknowledge financial support from the Spanish Ministry for Economy and Competitiveness (grants FIS2015-72482-EXP, FIS2015-64951-R, FIS2016-78591-C3-1-R, PGC2018-098613—B-C21, PGC2018-096047-B-I00, RTI2018-099737-B-I00 and MAT2014-53432-C5-5-R), the regional government of Comunidad de Madrid (grant S2018/NMT-4321), Universidad Autónoma de Madrid (UAM/48 and UAM/134) and IMDEA Nanoscience. Both IMDEA Nanoscience and IFIMAC acknowledge support from the Severo Ochoa and Maria de Maeztu Programmes for Centres and Units of Excellence in R&D (MINECO, Grants SEV-2016-0686 and MDM-2014-0377). We also acknowledge support by the QuantERA program of the European Union with funding by the Spanish AEI through project PCI2018-093145

Synthetic fuel production from renewable energy sources like biomass is gaining importance driven by the ambitious targets for reducing greenhouse gas emissions worldwide. Sorption enhanced gasification (SEG) proposes carrying out the gasification of biomass in the presence of a CO2 sorbent, which allows producing a syngas with a suitable composition for a subsequent synthetic fuel production step. This study aims at analysing the effect of different operating parameters (e.g. steam-to-carbon (S/C) ratio, CO2 sorption capacity and sorbent-to-biomass ratio) in the syngas composition and char conversion obtained in a 30 kWth bubbling fluidized bed gasifier, using grape seeds as feedstock. The importance of reducing the formation of higher hydrocarbons through a high steam-to-carbon ratio and using a CO2 sorbent with high sorption capacity is assessed. C3-C4 and unsaturated C2 hydrocarbons contents below 1%vol. (in dry and N2 free basis) can be achieved when working with S/C ratios of 1.5 at gasification temperatures from 700 to 740 °C. Varying the amount of the CO2 separated in the gasifier (by modifying the temperature or the CO2 sorption capacity of the sorbent) the content of H2, CO and CO2 in the syngas produced can be greatly modified, resulting in a module M=(H2-CO2)/(CO+CO2) that ranges from 1.2 to almost 3. ; This work has been carried out as part of the European Commission Horizon 2020 Framework Programme project FLEDGED (Grant agreement No. 727600) and the project WASYNG (No. RTI2018-095575-BI00) funded by the Spanish Ministry of Science, Innovation and Universities. Authors thank also the Regional Aragon Government (DGA) for the economic support under the research groups' support programme.

Toxoplasmosis is a parasitic disease caused by the protozoan Toxoplasma gondii, characterized by a clinical or subclinical infection attributed mainly to the isolate of the parasite responsible for the infection. Although domestic felines are considered the only urban hosts of this parasite and, consequently, the animals responsible for perpetuating T. gondii cycle in this environment, there is still a lack of information regarding the potential of different strains/isolates of this parasite and appearance of clinical signs during infection in domestic felines. In this context, the objective of the present study was to evaluate the clinical, parasitological, and serological characteristics of toxoplasmosis in felines infected with T. gondii isolates type I (RH strain) and III (P strain). Twelve healthy and serologically negative felines were selected for T. gondii (IgG titer < 16). These animals were divided into three experimental groups, GI: (P1, P2, P3, and P4) inoculated with 600 cysts of T. gondii (P strain), GII: (RH1, RH2, RH3, and RH4) inoculated with 2 × 105 tachyzoites (RH strain), and GIII: (C1, C2, C3, and C4) uninoculated. From the seventh day before (day ?7) to the 70th day after inoculation (DAI), the animals were observed daily to verify the occurrence of alterations in the digestive, nervous, locomotor, cardiorespiratory, and urinary systems, as well as skin and appendages. The clinical signs most observed in felines inoculated with T. gondii were apathy, hyporexia, shivering, nasal secretion, ocular secretion, and diarrhea. The results obtained in this study allow inferring that T. gondii isolate type I (RH strain) was more pathogenic to feline species than isolate type III (P strain), although both showed clinical symptomatology in all infected animals.

Caching is an enabler to avoid congestion and delay in the backhaul links of future 5G networks. The basic idea behind this concept consists in estimating the content that would be most likely requested by the end users served by each edge node and, after that, make a pro-active placement of those files during the traffic off-peak hours. Optical wired/wireless terrestrial links support a high point-to-point data rate but, when the same content needs to reach different destinations, parallel unicast transmissions are needed. On the other hand, satellite systems provide a lower link-level data rate but can easily implement a multicast transmission due to their wide-area coverage. In this paper, a resource allocation strategy that determines the most convenient way to transport the different content using both terrestrial (optical) and satellite (radio) technologies is proposed. Simulation results show that the placement time can be notably reduced in a hybrid terrestrial-satellite backhaul network, particularly in case of bad weather that impacts the data rate of the wireless optical links. The effect of the file popularity distribution and the number of 5G edge nodes on the delivery time is also studied in detail. ; Grant numbers : Project TERESA-TEC2017-90093-C3-1-R (AEI/FEDER, UE), and by the Catalan government under grant 2017 SGR 1479. © 2019 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.

(c) 2019 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other users, 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 components of this work in other works. ; [EN] In this paper, a novel form of the folded normal (FN) distribution has been proposed to model the small-scale fading in wireless communications. From a multiple-input multiple-output (MIMO) measurement campaign conducted in a lab environment with the line-of-sight (LOS) conditions at both the 60 and the 94 GHz bands, the authors obtain the parameters of the Rician, FN, and kappa-mu distributions. These parameters have been calculated by using the least square (LS) approximation and with techniques of statistical inference. The FN distribution provides the best fitting to the experimental results using the Kolmogorov-Smirnov (K-S) test for the inferred estimators with values of the ful llment of 100% and 69.82% at the 60 and 94 GHz bands, respectively, for a significance level of 1%. ; This work was supported by the Ministerio de Economia, Industria y Competitividad of the Spanish Government under the national projects TEC2017-86779-C2-2-R and TEC2016-78028-C3-2-P, through the Agencia Estatal de Investigacion (AEI) and the Fondo Europeo de Desarrollo Regional (FEDER). ; Reig, J.; Rodrigo Peñarrocha, VM.; Rubio Arjona, L.; Martínez-Inglés, MT.; Molina-García-Pardo, JM. (2019). The Folded Normal Distribution: A New Model for the Small-Scale Fading in Line-of-Sight (LOS) Condition. IEEE Access. 7:77328-77339. https://doi.org/10.1109/ACCESS.2019.2921340 ; S ; 77328 ; 77339 ; 7

6 Figuras.- 3 Tablas ; Synthetic fuel production from renewable energy sources like biomass is gaining importance driven by the ambitious targets for reducing greenhouse gas emissions worldwide. Sorption enhanced gasification (SEG) proposes carrying out the gasification of biomass in the presence of a CO2 sorbent, which allows producing a syngas with a suitable composition for a subsequent synthetic fuel production step. This study aims at analysing the effect of different operating parameters (e.g. steam-to-carbon (S/C) ratio, CO2 sorption capacity and sorbent-to-biomass ratio) in the syngas composition and char conversion obtained in a 30 kWth bubbling fluidized bed gasifier, using grape seeds as feedstock. The importance of reducing the formation of higher hydrocarbons through a high steam-to-carbon ratio and using a CO2 sorbent with high sorption capacity is assessed. C3-C4 and unsaturated C2 hydrocarbons contents below 1%vol. (in dry and N2 free basis) can be achieved when working with S/C ratios of 1.5 at gasification temperatures from 700 to 740 °C. Varying the amount of the CO2 separated in the gasifier (by modifying the temperature or the CO2 sorption capacity of the sorbent) the content of H2, CO and CO2 in the syngas produced can be greatly modified, resulting in a module M = (H2-CO2)/(CO + CO2) that ranges from 1.2 to almost 3. ; This work has been carried out as part of the European Commission Horizon 2020 Framework Programme project FLEDGED (Grant agreement No. 727600) and the project WASYNG (No. RTI2018-095575-B-I00) funded by the Spanish Ministry of Science, Innovation and Universities. Authors thank also the Regional Aragon Government (DGA) for the economic support under the research groups' support programme. ; Peer reviewed

Blending supplementary cementitiousmaterialswith portland cement is one of the current strategies for producingmore eco-efficient binders by lowering the energy consumption and CO2 emissions intrinsic to OPCmanufacture. The effect of such additions on heat of hydration and energy performance is a subject of particular interest, for higher heatmay reduce the service life of a concrete structure,whilst energy consumption per tonne of binder or megapascal may prove not to be energy-efficient. This paper explores the energy performance of granite sludge (GS) as an active addition to clinker and the effect of this by-product on heat of hydration and ecoefficiency. The findings show that maximum heating and total heat released are lower in the additioned than in the conventional material, with the difference widening at higher replacement ratios. At 35% GS, maximum heating was 36% lower than in OPC and total heat released 24% lower. Optimal energy performance is observed at ratios of 15% to 30% (both inclusive), with the experimental materials requiring less energy (−1.6 kW·h·t−1/MPa – 0.8 kW·h·t−1/MPa) than ordinary cement per megapascal (MPa) of strength. Cements with 15% to 30% granite sludge are consequently eco-efficient. With 15% GS they can be classified as ordinary (N270 J/g at 41 h),with 20% to 30% as lowheat cements (b270 J/g at 41 h) andwith 35% as very lowheat cements (b220 J/g at 41 h). ; This research was funded by the Spanish Ministry of Economy and Competitiveness (BIA2016-76643-C3-1-R) (MINECO/ERDF), as well as by the Government of Extremadura and the European Regional Development Fund (ERDF) under grant GR 18122 awarded to the MATERIA research group. ; Peer reviewed

Dissociating economic growth from the use of natural resources is imperative to the sustainable development of the construction industry. The use of secondary raw materials by processing and managing construction and demolition waste (C&DW) is one of the major challenges to transition to a circular economy. This study assessed the effect of simultaneously using cement additioned with the ceramic (fired clay-based) fraction of C&DW and recycled mixed aggregate (RMA) in concrete manufacture by analysing fresh concrete workability, density and air content and hardened concrete compressive, flexural and splitting tensile strength. Regression and variance analyses were run on the findings to determine the effect of RMA and cement type and their interaction on the dependent variables. The percentage of RMA was observed to be the most significant determinant for concrete density and air content. Early age compressive strength was impacted by cement type, although strength in the later age materials was comparable to that of concrete manufactured with conventional cement. The combined effect of cement type and percentage of RMA appeared to have no significant effect on tensile or flexural strength. On the contrary, the differences observed in these properties were due to the separate effect of each factor. The findings showed that the use of cement containing C&DW additions and up to 50% RMA did not substantially compromise concrete performance. ; This study was funded by the Spanish Ministry of Science and Innovation under project BIA2016-76643-C3-1-R, as well as by the Government of Extremadura and ERDF under grant GR 18122 awarded to the MATERIA research group. One of the authors benefitted from Ministry of Education, Culture and Sport pre-doctoral grant FPU16/02693. ; Peer reviewed