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In this article, it is intended to evaluate the performances of previously synthesized different nanometric compounds as SOFC components under real conditions. For this purpose, anodic supports SOFCs have been manufactured in different configurations. The compounds NiO-(Y2O3)0.08(ZrO2)0.92 (NiO–YSZ), (Y2O3)0.08(ZrO2)0.92 (YSZ), Sm0.2Ce0.8O1.9 (SDC), La0.6Sr0.4FeO3 (LSF) and LaNi0.6Fe0.4O3 (LNF) were used as anode support, electrolyte, barrier, cathode and contact layer, respectively. To obtain the cells, the anode supports were produced by uniaxial pressing and the remaining layers were added using the airbrush technique, assembling them by different sintering processes. The cells developed have been electrochemically tested in a temperature range between 750 and 865 °C. Additionally, degradation tests have been carried out under constant current. Moreover, to characterize the microstructure of the cells, a scanning electron microscope (SEM) equipped with an energy dispersive X-ray spectroscopy (EDX) analyzer has been used. The results obtained show that the incorporation of cathode and contact layers increases the power densities and decreases the total resistances of the cells with respect to the cell without cathode, especially with the addition of the LNF contact layer. Despite the improvement obtained, more tests have to be carried out in order to optimize the performance of SOFC devices in degradation tests.

Thin Fe19Ni81 films were deposited by magnetron sputtering technique onto cyclo olefin (COC) flexible polymer substrates. COC/FeNi(15 nm), COC/FeNi(23 nm), COC/FeNi(25 nm) and COC/FeNi(84 nm) composites were obtained and studied using structural, magnetic and microwave measurements. COC/FeNi(84 nm) composite, which still had certain transparency insured a complete protection with respect to the component of microwave signal polarized along the gunn diode axis (frequency of 10.52 GHz). Even most thin (15 nm) FeNi film was almost as effective as 84 nm film but having much higher transparency acceptable for microfluidic devices. Obtained results indicate that fabricated flexible composites can be used as effective shielding materials in complex multipurpose devices.

Polylactide (PLA) is among the most commonly used polymers for biomedical applications thanks to its biodegradability and cytocompatibility. However, its inherent stiffness and brittleness are clearly inappropriate for the regeneration of soft tissues (e.g., neural tissue), which demands biomaterials with soft and elastomeric behavior capable of resembling the mechanical properties of the native tissue. In this work, both L- and D,L-lactide were copolymerized with ethylene brassylate, a macrolactone that represents a promising alternative to previously studied comonomers (e.g., caprolactone) due to its natural origin. The resulting copolymers showed an elastomeric behavior characterized by relatively low Young’s modulus, high elongation at break and high strain recovery capacity. The thermoplastic nature of the resulting copolymers allows the incorporation of nanofillers (i.e., carbon nanotubes) that further enable the modulation of their mechanical properties. Additionally, nanostructured scaffolds were easily fabricated through a thermo-pressing process with the aid of a commercially available silicon stamp, providing geometrical cues for the adhesion and elongation of cells representative of the nervous system (i.e., astrocytes). Accordingly, the lactide and ethylene brassylate-based copolymers synthesized herein represent an interesting formulation for the development of polymeric scaffolds intended to be used in the regeneration of soft tissues, thanks to their adjustable mechanical properties, thermoplastic nature and observed cytocompatibility. Grant PID2019-106236GB-I00 funded by MCIN/AEI/10.13039/501100011033. The authors are also thankful for funds from the Basque Government, Department of Education (IT-1766-22). C.B.-Á.: acknowledges the predoctoral grant funded by the UPV/EHU. Polimerbio and Y.P. have a Bikaintek Ph.D. grant (20-AF-W2-2018-00001).

Aging dams and the rising efforts to restore stream ecosystems are increasing the number of dam decommissioning programs. Although dam decommissioning aims at improving in-stream habitat, biodiversity, and ecosystem functioning in the long term, it might also cause ecological impacts in the short term due to the mobilization of the sediment accumulated in the reservoir. Benthic biofilm in particular can be impaired by episodes of high turbidity and scouring. We conducted a multiple before-after/control-impact experiment to assess the effects of the drawdown of a large dam (42 m tall), a first step to its decommissioning, on biofilm structure (biomass and chlorophyll-a) and functioning (metabolism, nutrient uptake, and organic matter breakdown). Our results show that the reservoir drawdown reduced the autotrophic biofilm biomass (chlorophyll-a) downstream from the dam, which in turn lowered metabolism. However, nitrogen and phosphorus uptake by the biofilm was not affected. Organic matter breakdown was slower below the dam than in nearby undammed reaches before and during drawdown. All drawdown effects quickly disappeared and reaches downstream from the dam approached values found in nearby undammed reaches. Thus, our results indicate that the effects of reservoir drawdown on stream biofilms exist but may be small and disappear rapidly. This research was supported by the Fundación BBVA (064-17). The authors also acknowledge the financial support from the Basque Government (Consolidated Research Group: Stream Ecology 7-CA-18/10) predoctoral fellowships from the University of the Basque Country UPV/EHU (M.A.). The authors are especially grateful to the municipality of Donostia-San Sebastian and the staff of Artikutza for their continuous support during the experiment.

The habitat heterogeneity hypothesis states that increased habitat heterogeneity promotes species diversity through increased availability of ecological niches. We aimed at describing the local-scale (i.e. nest and adjacent substrate) effects of nests of the sea lamprey (Petro- myzon marinus L.) as ecosystem engineer on macroinvertebrate assemblages. We hypoth- esized that increased streambed physical heterogeneity caused by sea lamprey spawning would modify invertebrate assemblages and specific biologic traits and promote reach-scale diversity. We sampled thirty lamprey nests of the Nive River, a river of the south western France with a length of 79.3 km and tributary of the Adour River, in three zones: the unmodi- fied riverbed (upstream) and zones corresponding to the nest: the area excavated (pit) and the downstream accumulation of pebbles and cobbles (mound). The increased habitat het- erogeneity created by lamprey was accompanied by biological heterogeneity with a reduced density of invertebrates (3777 ± 1332 individuals per m2 in upstream, 2649 ± 1386 individu- als per m2 in pit and 3833 ± 1052 individuals per m2 in mound) and number of taxa (23.5 ± 3.9 taxa for upstream, 18.6 ± 3.9 taxa in pit and 21.2 ± 4.5 taxa for mound) in the pit com- pared to other zones. However the overall taxa diversity in nest increased with 82 ± 14 taxa compared to the 69 ± 8 taxa estimated in upstream zone. Diversity indices were consistent with the previous results indicating a loss of α diversity in pit but a higher β diversity between a pit and a mound than between two upstream zones, especially considering Morisita index accounting for taxa abundance. Trait analysis showed high functional diversity within zones with a reduced proportion of collectors, scrapers, shredders, litter/mud preference and small invertebrates in mound, while the proportion of “slabs, blocks, stones and pebbles” prefer- ence and largest invertebrates increased. Pit presented the opposite trend, while upstream had globally intermediate trait proportions. Our results highlight important effects on species and functional diversity due to habitat heterogeneity created by a nest-building species, what can ultimately influence food webs and nutrient processes in river ecosystems Functioning was financed by Pole Gestion des Migrateurs Amphihalins dans leur Environnement (https://www6.rennes.inrae.fr/u3e/PRESENTATION/Organisation/Pole-MIAME).M.D.PhDs was financed by University of Pau and Pays de l'Adour (https://www.univ-pau.fr/fr/index.html) and UPV/EHU (https://www.ehu.eus/es/home).Field work used resources from the IE ECP Experimental Facility of the UMR Ecobiop (https://www6.bordeaux-aquitaine.inrae.fr/ie-ecp-ecobiop).The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Grant no. IT1471-22 from the Basque Government funded this study.

Polymer capsules fabricated via the layer-by-layer (LbL) approach have emerged as promising biomedical systems for the release of a wide variety of therapeutic agents, owing to their tunable and controllable structure and the possibility to include several functionalities in the polymeric membrane during the fabrication process. However, the limitation of the capsules with a single functionality to overcome the challenges involved in the treatment of complex pathologies denotes the need to develop multifunctional capsules capable of targeting several mediators and/or mechanisms. Oxidative stress is caused by the accumulation of reactive oxygen species [e.g., hydrogen peroxide (H2O2), hydroxyl radicals (•OH), and superoxide anion radicals (•O2-)] in the cellular microenvironment and is a key modulator in the pathology of a broad range of inflammatory diseases. The disease microenvironment is also characterized by the presence of proinflammatory cytokines, increased levels of matrix metalloproteinases, and acidic pH, all of which could be exploited to trigger the release of therapeutic agents. In the present work, multifunctional capsules were fabricated via the LbL approach. Capsules were loaded with an antioxidant enzyme (catalase) and functionalized with a model drug (doxorubicin), which was conjugated to an amine-containing dendritic polyglycerol through a pH-responsive linker. These capsules efficiently scavenge H2O2 from solution, protecting cells from oxidative stress, and release the model drug in acidic microenvironments. Accordingly, in this work, a polymeric microplatform is presented as an unexplored combinatorial approach applicable for multiple targets of inflammatory diseases, in order to perform controlled spatiotemporal enzymatic reactions and drug release in response to biologically relevant stimuli.

FeNi/FeMn/GdxCo100-x multilayered films were prepared by magnetron sputtering. The Gd–Co layer had different temperature dependences of the spontaneous magnetization due to the different Gd content. The magnetic properties of the films were determined from hysteresis loops measured in the temperature range 5–473 K. In order to determine the existence of a long-range interaction and a mutual influence of two exchange bias systems through the formation of bulk continuous magnetic structure in the antiferromagnetic layer special cooling procedure with FeNi and Gd–Co magnetizations saturated in a direction parallel or antiparallel to each other was used. The observed difference in the exchange bias between the two cooling configurations was discussed.

The magnetic properties of the [Tb–Co/Si]n films are studied at temperatures of 5–300 K. The regularities of changing the effective magnetic moment of terbium and the average magnetic moment of cobalt with decreasing magnetic layer thickness are determined. In this case, interlayer interfaces are shown to play the active role. A decrease in the Tb–Co layer thickness is accompanied by an increase in the opening angle of sperimagnetic cone and the transition from the sperimagnetic to speromagetic structure.

Human Dental Pulp Stem Cells (hDPSCs) are one of the most promising stem cell sources for tissue engineering and regeneration, due to their extraordinary multi-lineage differentiation ability, ease of extraction from biological waste in dental clinics, safe non-tumorigenic phenotype, immune-tolerance upon in vivo transplantation, and great possibilities of application in autologous tissue reconstruction. The in vitro manipulation of hDPSCs paves the way for drug screening and tailor-made regeneration of damaged tissues, in the context of personalized medicine. The neural crest phenotype of these stem cells gives them the capacity to differentiate to a large variety of cell types, including neural-lineage cells. In this chapter, we describe various culture methods to generate different cellular phenotypes from hDPSCs, which can not only grow as mesenchymal-like plastic adherent cells, but also as non-adherent neurogenic dentospheres in serum-free medium. Floating dentospheres can be used to generate large populations of mature neuronal and glial marker expressing cells, which may be cultured over a substrate of nanopatterned scaffold based on biodegradable poly(lactide-co-caprolactone) (PLCL) to induce a controlled alignment of neurites and cell migration, to generate in vivo biocompatible constructs for nerve tissue bioengineering.

–The effect of heat treatment (HT) on the structural features, magnetic properties, and magnetic impedance of rapidly quenched Fe73.5Si13.5B9Nb3Cu1 ribbons and doped ribbons, in which 10 wt % iron is replaced by either cobalt, nickel, or manganese, is studied in this paper. Cobalt ribbons as a result of HT at a constant temperature showed a significant increase in the value of maximum magnetic induction. The magnetic and magnetic-impedance properties, studied in a wide range of alternating current frequencies from 1 to 400 MHz, showed a significant change in the features of effective magnetic anisotropy and high-frequency responses after HT. A comparative analysis of the results obtained for samples of various compositions can be useful both for understanding the features of the formation of effective magnetic anisotropy in nanocrystalline alloys and from the point of view of practical applications in the search for optimal physicochemical parameters of materials for sensors of low magnetic fields.

Destinezite, ideally Fe23+(PO4)(SO4)(OH)·6(H2O), is found as nodular lumps in hematite-rich epiclastic sediments accumulated in small crater lakes on the slopes of El Laco volcano. These lumps are almost entirely dominated by fine-grained destinezite replacing earlier lipscombite, and associated with gray hematite. The crystal structure of destinezite has been re-examined to test for possible differences with respect to the earthy and poorly crystalline destinezite that forms by weathering in cave soils and mine waste dumps. The structural refinements confirm that the differences are minor. The El Laco destinezite was refined in space group P1 with a = 9.5828(2), b = 9.7440(3), c = 7.3302(3) Å, and α = 98.796(3)°, β = 107.985(3)°, γ = 63.898(2)°, V = 584.50(4) Å3, and Z = 1. We measured by calorimetry the enthalpy and derived the entropy and the Gibbs free energy of formation of destine-zite (–4051.7 ± 4.3, –1518.5 ± 20.0, and –3598.9 ± 7.1 kJ/mol, respectively). This has allowed us to estimate the equilibrium constant in the temperature range 0–300 °C (log K = –27.97 ± 1.1). We can predict that destinezite coexists with hematite over the range of conditions that typically encompass the steam-heated hydrothermal environments recognized at El Laco. The presence of destinezite along with hematite and the occurrence of alunite, jarosite, and variscite in the system provide evidence of intense hydrothermal alteration during the extrusion of Fe-rich melts at El Laco volcano. The mineral assemblage and the available geochemical data suggest that destinezite formed in hydrothermal conditions by “maturation” of an immiscible Fe–P-rich melt. An unknown Fe–P–O phase produced by this melt was first replaced by lipscombite and later, owing to intense sulfidation, by destinezite. This replacement took place in the vadose zone above the paleowater table by relatively cool (

[EN] Water diversion and pollution are two pervasive stressors in river ecosystems that often co-occur. Individual effects of both stressors on basal resources available to stream communities have been described, with diversion reducing detritus standing stocks and pollution increasing biomass of primary producers. However, interactive effects of both stressors on the structure and trophic basis of food webs remain unknown. We hypothesized that the interaction between both stressors increases the contribution of the green pathway in stream food webs. Given the key role of the high-quality, but less abundant, primary producers, we also hypothesized an increase in food web complexity with larger trophic diversity in the presence of water diversion and pollution. To test these hypotheses, we selected four rivers in a range of pollution subject to similar water diversion schemes, and we compared food webs upstream and downstream of the diversion. We characterized food webs by means of stable isotope analysis. Both stressors directly changed the availability of basal resources, with water diversion affecting the brown food web by decreasing detritus stocks, and pollution enhancing the green food web by promoting biofilm production. The propagation of the effects at the base of the food web to higher trophic levels differed between stressors. Water diversion had little effect on the structure of food webs, but pollution increased food chain length and trophic diversity, and reduced trophic redundancy. The effects at higher trophic levels were exacerbated when combining both stressors, as the relative contribution of biofilm to the stock of basal resources increased even further. Overall, we conclude that moderate pollution increases food web complexity and that the interaction with water abstraction seems to amplify this effect. Our study shows the importance of assessing the interaction between stressors to create predictive tools for a proper management of ecosystems. Ministerio de Economia, Industria y Competitividad, Gobierno de Espana, Grant/Award Number: GL2016-77487-R; European Social Fund; Diputacion Foral de Bizkaia; Serra Hunter Fellow; Labex, Grant/Award Number: ANR-10-LABX-41; H2020 European Research Council; Eusko Jaurlaritza; Consejo Nacional de Investigaciones Cientificas y Tecnicas; FRAGCLIM Consolidator, Grant/Award Number: 726176

Ongoing global warming is expected to alter temperature-dependent processes. Nevertheless, how co-occurring local drivers will influence temperature sensitivity of plant litter decomposition in lotic ecosystems remains uncertain. Here, we examined the temperature sensitivity of microbial-mediated decomposition, microbial respiration, fungal biomass and leaf nutrients of two plant species varying in litter quality. We also assessed whether the type of microbial community and stream water characteristics influence such responses to temperature. We incubated alder (Alnus glutinosa) and eucalypt (Eucalyptus globulus) litter discs in three streams differing in autumn–winter water temperature (range 4.6–8.9 °C). Simultaneously, in laboratory microcosms, litter discs microbially conditioned in these streams were incubated at 5, 10 and 15 °C with water from the conditioning stream and with a water control from an additional stream. Both in the field and in the laboratory, higher temperatures enhanced litter decomposition rates, except for eucalypt in the field. Leaf quality modified the response of decomposition to temperature in the field, with eucalypt leaf litter showing a lower increase, whereas it did not in the laboratory. The origin of microbial community only affected the decomposition rates in the laboratory, but it did not modify the response to temperature. Water quality only defined the phosphorus content of the leaf litter or the fungal biomass, but it did not modify the response to temperature. Our results suggest that the acceleration in decomposition by global warming will be shaped by local factors, mainly by leaf litter quality, in headwater streams. Open Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature. This research was financed by the Ministry of Science and Innovation of the Spanish Government (CGL2010-22129-C04-01). S. Monroy was supported by a predoctoral grant by the Spanish Ministry of Economy and Competitiveness (BES-2012–060743) and a postdoctoral grant from the University of the Basque Country (DOKBERRI 2018 I).

The conductivity of ceramic ionic materials is highly influenced by dopant segregation at the grain boundaries or interfaces, which usually induces a depletion of charge carriers by space charge effects. Hence, obtaining interfacial configurations that promote the formation of oxygen vacancies is highly desirable. In this paper we have combined high resolution electron microscopy (HREM), kelvin probe force microscopy (KPFM) and density functional theory (DFT) to elucidate the equilibrium state of CGO–CoO and CGO–NiO eutectic ceramics (CGO: cerium-gadolinium oxide). HREM proves that the interface is sharp, formed by a single common oxygen plane, and that in CGO–CoO the concentration of gadolinium ions at the interface is almost three times greater than in the bulk, while they distribute homogeneously in the CGO–NiO system. Accordingly, KPFM experiments suggest that interfacial ionic conductivity is much higher in CoO–CGO than in NiO–CGO. DFT demonstrates that Gd segregation in the CGO–CoO reduces the interface energy, contributing to its stability. The Gd-oxygen vacancy complexes compensate the interfacial ionic charge density discontinuity. Additionally, the induced local distortions around the defect release the strain associated with the lattice mismatch. Therefore, we show that in CGO-based eutectics the structure and ionicity of the constituent oxides are essential to promote the interface dopant segregation, indicating a new way to produce nanocomposites with enhanced interfacial ionic conductivity., This work was funded through MAT2015-68078-R, MAT2015-66888-C3-1R, MAT2016-80762-R and RTI2018-097895-B-C41 projects by the Spanish Government (Ministerio de Economía y Competitividad) and the Feder Programme of the European Union. Financial support from Xunta de Galicia (Centro singular de investigación de Galicia, accreditation 2016–2019, ED431G/09) is also recognized. F. W. acknowledges the financial support of the China Scholarship Council (CSC) during her stay at the ICMM.

Resumen: En este trabajo se propone el empleo de la técnica de electro-hilado para la síntesis de fibras cerámicas que puedan ser empleadas como constituyentes de electrodos de pilas de combustible de óxido sólido. Concretamente se ha demostrado el aumento en la capacidad de producción de fibras cerámicas (en un orden de magnitud) gracias a la sustitución de un inyector simple por uno múltiple (provisto de 10 agujas). Además, los diámetros, longitudes, tamaños de cristal y área superficial de las fibras obtenidas indican que estas podrían ser empleadas para fabricar electrodos con una microestructura altamente porosa, fácilmente infiltrable y donde se maximice la región donde tiene lugar la reacción de reducción de oxígeno y el transporte de gases y cargas. Abstract: In this work, we propose the use of electro-spinning technique for the synthesis of ceramic fibers that can be used as SOFC's electrodes. In particular, the increase of ceramic fibers production capacity (up to one order of magnitude) has been demonstrated through the replacement of a single injector by a multiple injector (equipped with 10 needles). Moreover, the diameters, lengths, glass sizes and surface area of the obtained fibers indicate that these fibers could be used to manufacture highly porous electrodes that can be easily infiltrated, having micro-structure where the oxygen reduction reaction region takes place is maximized and also the gases and charges transportations properties are improved. Palabras clave: Pilas de combustible de óxido sólido, Electro-hilado, Nanofibras, Inyector múltiple, Keywords: Solid oxide fuel cells, Electrospinning, Nanofibers, Multi-injector

Commercial yttria-stabilized zirconia Zr0.8Y0.2O1.9 (8YSZ), and five synthesized rare-earth aluminates Ln4Al2O9 (Ln = Y, Sm, Eu, Gd, Tb), were examined as possible intermediate-temperature barrier materials. The materials were directly deposited on preoxidized Fe-Cr metallic substrate, without bond coating as, using a wet colloidal spray technique. Phase purity and structures for all materials were confirmed by X-ray Diffraction (XRD) and the morphology of these compounds was examined using Scanning Electron Microscopy (SEM). The thermal resistance of the YSZ and Ln4Al2O9 (Ln = Y, Sm, Eu, Gd, Tb) layers was compared by the temperature drop method (∆T = Tsubstrate-Tsubstrate with coating), using an in-house built set up. Prior to measurement, the reproducibility and stability of the proposed experiment was confirmed. For the Eu4Al2O9 and Tb4Al2O9 coatings with thicknesses near 60 μm, the thermal resistance capability (≈180 °C) at 800 °C, was similar to that of the 8YSZ coating (commercial material for Thermal Barrier Coating (TBC) development). The cross-sectional microstructure of the samples, after thermal analysis was also examined, confirming no changes in the microstructure. Given the observed high thermal resistance capability values for the Ln4Al2O9 (Ln = Y, Sm, Eu, Gd, Tb) samples, and the possibility to change the porosity of the starting materials by ball milling, the results suggest that these materials have good potential for use as ceramic interlayers for TBCs.

Simuliid larvae are common inhabitants of mountain rivers throughout the world, where they can serve as ecological indicators. Black flies were sampled during three seasons in four rivers in the upper basin of the Bogotá River in the Colombian Andes, and physical, chemical, and hydrological data were recorded. Multivariate methods were used to determine the relationships between the presence and abundance of simuliid species and environmental characteristics. Fourteen species were found: eight in the genus Gigantodax (Enderlein, Diptera, Simuliidae) and six in the genus Simulium (Latreille, Diptera, Simuliidae). Dissolved oxygen, dissolved solids, redox potential, chemical oxygen demand, and nutrients contributed to an explanation of species distributions. Species in clean waters and in more polluted waters had narrow niches; those in low to moderately polluted waters had broader niches. Species in the lower reaches of the watercourses had greater turnover, perhaps because the most sensitive species had disappeared and been replaced by more tolerant species. Thus, simuliids can be used as predictors of environmental characteristics of Andean rivers and can be useful in the evaluation and management of these watersheds.

Crystal structure and hysteresis properties of Ni-Mn/FeNi-based films are studied with respect to the composition of the Ni-Mn layer, annealing conditions, temperature, and the presence of an auxiliary layer. The exchange bias is confirmed to originate from the pinning effect of the antiferromagnetic γ-NiMn (A1 fcc) or θ-NiMn (L10 fct) phases formed in the Ni-Mn layer through the epitaxial growth on the seed layer or due to the annealing, respectively. The composition range of Ni-Mn and annealing temperatures providing the formation of the antiferromagnetic phases are determined, as well as their influence on temperature dependences of the exchange bias field and coercivity of the FeNi layer.

In this work, a wet powder spraying method has been investigated as a facile low cost route to deposit electrode layer on SOFC electrolyte support. A particular focus has been examining the interfacial stability of the deposited layers, and determining the influence of the thickness of the different layers, as well as the ball milling regime used to produce the electrode inks. The developed system consist of an yttria stabilized zirconia electrolyte support, a La0.6Sr0.4FeO3 (LSF) cathode, a Sm0.2Ce0.8O1.9 (SDC) barrier layer between the electrolyte and the cathode, and LaNi0.6Fe0.4O3 (LNF) as a contact layer, for a future integration with the SOFC interconnector. The electrolyte supports (300 μm thickness and 9 mm diameter) supports were prepared by uniaxial pressing, while the deposition of thin barrier layers, cathode and contact layer were carried out by manual spray coating., This research has been funded by the Ministerio de Economía, Industria y Competitividad [MAT2016-76739-R and MAT2015-68078-R] [AEI/FEDER, UE] and Dpto. Educación of the Basque Government [IT-630-13]. The authors thanks the support received by the European Regional Development Fund (ERDF). The technical support of SGIker of UPV/EHU is gratefully acknowledged. A. Wain-Martin thanks Ministerio de Economía y Competitividad for funding his work [BES-2014-068433].

FeNi films of different thickness and FeNi/(Fe, Co)/FeNi trilayers were prepared by magnetron sputtering deposition onto glass substrates. The permalloy films had a columnar microstructure. The detailed analysis of the magnetic properties based on the magnetic and magneto-optical measurements showed that at thicknesses exceeding a certain critical thickness, hysteresis loops acquire a specific shape and the coercive force of the films increase sharply. The possibility of the estimation of the perpendicular magnetic anisotropy constant using the Murayama equation for the thickness dependence of saturation field was demonstrated. The results of studies of the structural and magnetic properties of FeNi films laminated by Fe and Co spacers with different thickness are presented. This research was funded by the Russian Science Foundation (RSF), project no. 22-29-00980, https://rscf.ru/en/project/22-29-00980/ and in part by the Research Groups of the UPV-EHU.

Clinical utility of conventional oral therapies is limited by their inability to deliver therapeutic molecules at the local or targeted site, causing a variety of side effects. Transdermal delivery has made a significant contribution in the management of skin diseases with enhanced therapeutic activities over the past two decades. In the modern era, various biomimetic and biocompatible polymer-lipid hybrid systems have been used to augment the transdermal delivery of therapeutics such as dermal patches, topical gels, iontophoresis, electroporation, sonophoresis, thermal ablation, microneedles, cavitational ultrasound, and nano or microlipid vesicular systems. Nevertheless, the stratum corneum still represents the main barrier to the delivery of vesicles into the skin. Lipid based formulations applied to the skin are at the center of attention and are anticipated to be increasingly functional as the skin offers many advantages for the direction of such systems. Accordingly, this review provides an overview of the development of conventional to advanced biomimetic lipid vesicles for skin delivery of a variety of therapeutics, with special emphasis on recent developments in this field including the development of transferosomes, niosomes, aquasomes, cubosomes, and other new generation lipoidal carriers.

The need for tree-derived industrial products is causing an increase in the land surface covered by fast-growing monoculture plantations throughout the world. Species planted are selected mostly prioritizing their rapid growth, with less consideration to minimizing the negative environmental effects they create. Among the various ecosystems that can be negatively affected by plantations, streams are among the most impacted, as they strongly depend on dead organic matter from the surrounding vegetation. Changes in land use in favour of monocultures can have large consequences on stream biodiversity and functioning since they can lead to alterations in the diversity, quantity, quality and timing of litter inputs. Here, we review the literature dealing with the effects of plantations on litter decomposition in streams, with special focus on eucalyptus and conifer plantations, which have been more thoroughly studied than other planted tree species. The effects of plantations on litter decomposition in streams have a degree of regional specificity, and depend on the composition of detritivores, litter characteristics (of native and exotic species) and local environmental conditions. There is, nonetheless, a need for further research describing the effects of specific planted exotic species and for more studies out of Europe and North America.

Tendon disease constitutes an unmet clinical need and remains a critical challenge in the field of orthopaedic surgery. Innovative solutions are required to overcome the limitations of current tendon grafting approaches, and bioelectronic therapies show promise in treating musculoskeletal diseases, accelerating functional recovery through the activation of tissue regeneration-specific signaling pathways. Self-powered bioelectronic devices, particularly piezoelectric materials, represent a paradigm shift in biomedicine, negating the need for battery or external powering and complementing existing mechanotherapy to accelerate the repair processes. Here, the dynamic response of tendon cells to a piezoelectric collagen-analogue scaffold comprised of aligned nanoscale fibers made of the ferroelectric material poly(vinylidene fluoride-co-trifluoroethylene) is shown. It is demonstrated that motion-powered electromechanical stimulation of tendon tissue through piezo-bioelectric device results in ion channel modulation in vitro and regulates specific tissue regeneration signaling pathways. Finally, the potential of the piezo-bioelectronic device in modulating the progression of tendinopathy-associated processes in vivo, using a rat Achilles acute injury model is shown. This study indicates that electromechanical stimulation regulates mechanosensitive ion channel sensitivity and promotes tendon-specific over non-tenogenic tissue repair processes.

Superparamagnetic iron oxide nanoparticles (SPIONs) are great adsorbents of toxic arsenic in water. However, SPIONs efficiency is limited by a tendency towards agglomeration, and an extra filtering process is required in actual applications to avoid possible harmful effects of nanoparticles released to the environment. Here, we show a novel green method to confine and disperse SPIONs (10 nm) inside insoluble electrospun PVA nanofibers (final concentration 0.14 wt. %). We found that the resulting membrane has an enhanced arsenic adsorption capacity (> 52 mg/g) and presents a new adsorption mechanism, involving a high swelling of the superhydrophilic nanofibers before actual solution interchange can occur. A suitable heat treatment provided water insolubility to the membrane while maintaining hydrophilicity and active sites in the SPIONs. We show the excellent dispersion and homogeneous distribution of the SPIONs inside the nanofibers using electron microscopies and scale this analysis to an area of statistical significance via magnetic studies and novel Small and Wide Angle X-Ray Scattering SAXS/WAXS 2D scannings. The production process is environmentally friendly, given that only PVA was used as SPIONs dispersant and no chemicals were added for crosslinking. This work presents a novel material that expands the broad technological applications of both iron oxide nanoparticles and electrospinning, opening a route to new horizons in water purification., We kindly acknowledge the financial support of UBA (UBACYT 2018-2020 No 20020170100381BA), ANPCyT (PICT 2017-2362, PICT 2017-3150) and the Ministerio de Ciencia, Innovación y Universidades code PID2019-104650GB-C21 (MCIU/AEI/FEDER, UE).

[EN]The use of three-dimensional (3D) printable hydrogels for biomedical applications has attracted considerable attention as a consequence of the ability to precisely define the morphology of the printed object, allowing patients' needs to be targeted. However, the majority of hydrogels do not possess suitable mechanical properties to fulfill an adequate rheological profile for printability, and hence, 3D printing of cross-linked networks is challenging and normally requires postprinting modifications to obtain the desired scaffolds. In this work, we took advantage of the crystallization process of poly(ethylene glycol) to print non-isocyanate poly(hydroxyurethane) hydrogels with tunable mechanical properties. As a consequence of the crystallization process, the hydrogel modulus can be tuned up to 3 orders of magnitude upon heating up to 40 degrees C, offering an interesting strategy to directly 3D-print hydrogels without the need of postprinting cross-linking. Moreover, the absence of any toxicity makes these materials ideal candidates for biomedical applications. The authors acknowledge financial support from the European Commission through SUSPOL-EJD 642671 project. M.C.A. thanks the University of Birmingham for funding.

Discharge reduction, as caused by water diversion for hydropower, and fine sediments deposition, are prevalent stressors that may affect multiple ecosystem functions in streams. Periphytic biofilms play a key role in stream ecosystem functioning and are potentially affected by these stressors and their interaction. We experimentally assessed the interactive effects of discharge and fine sediments on biofilm metabolism in artificial indoor channels using a factorial split-plot design with two explanatory variables: water discharge (20, 39, 62, 141 and 174 cm3 s-1) and fine sediments (no sediment or 1100 mg L-1 of sediments). We incubated artificial tiles for 25 days in an unpolluted stream to allow biofilm colonization, and then placed them into the indoor channels for acclimation for 18 days. Subsequently, we manipulated water discharge and fine sediments and, after 17 days, we measured biofilm chlorophyll-a concentration and metabolism. Water velocity (range, 0.5 to 3.0 cm s-1) and sediment deposition (range, 6.1 to 16.6 mg cm-2) increased with discharge, the latter showing that the effect of increased inputs prevailed over sloughing. In the no-sediment treatments, discharge did not affect biofilm metabolism, but reduced chlorophyll-a. Sediments, probably as a consequence of nutrients released, promoted metabolism of biofilm and chlorophyll-a, which became independent of water discharge. Our results indicate that pulses of fine sediments can promote biofilm algal biomass and metabolism, but show interactive effects with discharge. Although discharge reduction can affect the abundance of basal resources for food webs, its complex interactions with fine sediments make it difficult to forecast the extent and direction of the changes. This research was funded by the Spanish Department of Economy, Industry and Competitiveness through the project GL2016-77487-R(DIVERSION),the European Social Fund, the Basque Government (Consolidated Research Group IT951-16) and the Biscay Province Council (61/2015). AVPC carried out this workt hanksto a pre-doctoral grant by the Spanish Department of Economy, Industry and Competitiveness (BES-2017-081959). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

Human dental pulp stem cells (hDPSCs) are some of the most promising stem cell types for regenerative therapies given their ability to grow in the absence of serum and their realistic possibility to be used in autologous grafts. In this review, we describe the particular advantages of hDPSCs for neuroregenerative cell therapies. We thoroughly discuss the knowledge about their embryonic origin and characteristics of their postnatal niche, as well as the current status of cell culture protocols to maximize their multilineage differentiation potential, highlighting some common issues when assessing neuronal differentiation fates of hDPSCs. We also review the recent progress on neuroprotective and immunomodulatory capacity of hDPSCs and their secreted extracellular vesicles, as well as their combination with scaffold materials to improve their functional integration on the injured central nervous system (CNS) and peripheral nervous system (PNS). Finally, we offer some perspectives on the current and possible future applications of hDPSCs in neuroregenerative cell therapies. This research was supported by MICINN retos I+D+i (PID2019-104766RB-C21 and RYC-2013-13450, to J.R.P.) and UPV/EHU (GIU16/66 and PPGA20/22, to F.U., G.I.; and COLAB19/03 and IKERTU-2020.0155, to F.U., J.R.S.). Y.P. was funded by a Bikaintek PhD grant from the Basque Government (20-AF-W2-2018-00001).

peer-reviewed Biodegradable strain sensors able to undergo controlled degradation following implantation have recently received significant interest as novel approaches to detect pathological tissue swelling or non-physiological stresses. In this study, the physicomechanical, electrochemical and active pressure sensing behavior of an electrically conductive and biodegradable poly(glycerol sebacate urethane) (PGSU) composite, reinforced with poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) functionalized carbon nanotubes (CNTs), was evaluated in vitro. Analysis of these PGSU-CNTs composites demonstrated that the incorporation of functionalized CNTs into a biodegradable elastomer resulted in enhanced mechanical strength, conductivity and tailored matrix biodegradation. PGSU-CNT composites were subsequently formulated into flexible and active pressure sensors which demonstrated optimal sensitivity to applied 1% uniaxial tensile strains. Finally, cytocompatibility analysis a with primary neural culture confirmed that PGSU-CNT composites exhibited low cytotoxicity, and supported neuron adhesion, viability, and proliferation in vitro.

Tendon disease constitutes an unmet clinical need and remains a critical challenge in the field of orthopaedic surgery. Innovative solutions are required to overcome the limitations of current tendon grafting approaches, and bioelectronic therapies are showing promise in the treatment of musculoskeletal disease, accelerating functional recovery through the activation of tissue regeneration signalling pathways (guided regeneration). Self-powered bioelectronic devices, and in particular piezoelectric materials represent a paradigm shift in biomedicine, negating the need for battery or external powering and complementing existing mechanotherapy to accelerate the repair processes. Here, we show the dynamic response of tendon cells to a piezoelectric collagen-analogue scaffold comprised of aligned nanoscale fibres made of the ferroelectric material poly(vinylidenefluoride-co-trifluoroethylene), (PVDF-TrFE). We demonstrate that electromechanical stimulation of tendon tissue results in guided regeneration by ion channel modulation. Finally, we show the potential of the bioelectronic device in regulating the progression of tendinopathy associated processes using a rat Achilles tendinopathy model. This study indicates that body motion-powered electromechanical stimulation can control the expression of TRPA1 and PIEZO2 receptors and stimulate tendon-specific tissue repair processes.

International audience; Invertebrate drift is an important ecological process but factors affecting the downstream transport of invertebrates are difficult to assess. The influence of water velocity on drift entry rates is still unclear and has rarely been quantified. In this study, conducted in spring and autumn, we investigated the drift propensity for different sizes of Baetis, Simulium and Chironomus larvae which, over a 24-h period, were subjected to low, moderate or high water velocities (14, 30 and 40 cm s-1, respectively) in either fine or coarse gravel beds. Interspecific differences were detected: Baetis drifted the most, Chironomus showed intermediate values and Simulium drifted the least. Chironomus was the only taxon that responded to water velocity. Baetis and Simulium were only slightly constrained to drift by the experimental conditions, while, in contrast, Chironomus larvae were very sensitive to flow increase. Substrate size (fine/coarse gravel bed) had no effect on any taxa. Small Simulium and Chironomus drifted more than larger ones. A seasonal effect was also detected, with Baetis drifting more in fall and Simulium drifting more in spring. Results suggest that community structure may be as or more important than hydraulics as a determinant of drift rates.

Changes in land cover are one of the most extensive and influential human impacts on fluvial ecosystems. In this study, we assessed how changes in food resource quantity and type linked to forest cover affect mountain stream multitrophic macroinvertebrate community size structure. We tested whether the total organism biomass (size spectrum intercept) and the energy transfer efficiency among trophic levels (size spectrum slope) are altered. Community size spectra slopes remained unchanged with variations in food resource type, while intercept increased with resource quantity. This pointed to an internal compensatory regulation of the community size structure for the maintenance of trophic transfer efficiency, only adjusting the total organism biomass to total food resource quantity through variations in organism abundance. Community size structure consistency was related to detritivore-omnivore substitutions, although the shifts in size structure with variations in the degree of allochthony differed between these feeding groups. Omnivore change was numerical (i.e., increase in large organism density with a decrease in allochthony) not related to body size or taxonomic composition. In contrast, detritivores showed a reduction in body size with the decrease in allochthony that did not coincide with a reduction in total biomass or density, but was related to a taxonomic replacement of larger case-building trichopterans by smaller detritivores. These findings elucidate how the size structure of a multitrophic macroinvertebrate community might respond to changes in forest cover, shedding light on the effects of global environmental change on the structure and stability of stream food webs.

Stainless steels, especially the austenitic grades, present a good corrosion resistance but poor mechanical properties. Nitriding can increase the surface hardness but typically at the expense of corrosion resistance. Besides, nitriding of inner surfaces is not straight forward, as control of the plasma there is challenging. This work has focused on the development of active screen plasma nitriding processes of inner geometries of the widely used AISI 316L austenitic stainless steel, with preservation of the corrosion resistance. The structure and composition of the nitrided surfaces were studied and corrosion resistance of the inner surfaces assessed. As a result of the study, a relation has been established between plasma treatment parameters, geometrical features and the corrosion resistance. Additionally, electro-tribological studies have been performed. It has been observed that wear resistance improved and that ECR (Electrical Contact Resistance) is a good indicator of the wear phenomena occurring along the test and potentially could be a useful and simple monitoring tool of the status of the surface and assist in defining safe and dependable operational lives. As part of the study, an equivalent electric circuit is proposed. In conclusion, treatment conditions for AISI316L inner tube surfaces have been defined, with corrosion resistance preservation and improved tribological performance, while ECR monitoring has been found insightful and informative of the evolution of the later.

Specialty alloys such as precipitation hardening stainless steels are routinely used in critical applications requiring high strength and corrosion resistance, e.g. in aeronautics, in ground transportation and the biomedical field. Nonetheless, their tribological properties remain poor, while the application of surface treatments results in loss of corrosion resistance. Therefore, typically a not fully satisfactory compromise must be adopted. In the present work, the improvement of tribological features, without loss of corrosion resistance, of the 1.4545 (15-5PH) steel has been explored with the use of high density plasmas. The work has focused on long cylindrical geometries, close to those of real applications. The microstructure and composition of the treated surfaces were studied and the corresponding corrosion resistance stablished. The characteristics of the high density plasmas as well as the sample disposition were key factors in the outcomes, which ranged from fully corroded to corrosion resistant surfaces. Results also showed in certain cases the high density plasmas causing surface cracks followed by local corrosion. Additionally tribological studies demonstrated improvement in wear resistance, and electrical contact resistance (ECR) was found to be a good indicator of the wear phenomena occurring along the tests. An equivalent electric circuit is proposed. Actually ECR could be a useful and simple way of monitoring the surface status and assist in assuring safe and dependable operational lives of the components. In conclusion, treatment conditions of cylindrical 1.4545 (15-5PH) have been defined, which provide with an improved tribological performance, preserving corrosion resistance, with ECR a useful performance monitoring parameter. This work was supported the ProSurface project by MINECO (Spanish Ministry of Economy and Competitiveness) under grant No. RTC-2015-3595-4 and by the Economic Development Department at the Basque Government under Elkartek nG-17 grant.

The influence of the nanoscale thicknesses of the ferrimagnetic Tb-Co layers on the structure and magnetic properties of magnetron sputtered Tb-Co/Ti and Tb-Co/Al2O3 magnetic multilayers were comparatively studied. Low angle X-ray diffraction patterns testified to the existence of a well defined layered structure in all the cases under consideration. For all samples, the magnetization was positioned in the plane of the films in the entire investigated temperature interval from 5 to 350 K. The temperature dependence of magnetization of the multilayered structures is the function of the Tb-Co layer thickness. The material of the spacers was shown to significantly influence the magnetic properties of the multilayers.

Excess reactive oxygen species (ROS) has been implicated in numerous diseases including cancer, cardiovascular and neurodegenerative diseases. Overexpression of ROS can lead to oxidative stress and subsequently to H2O2-mediated cell apoptosis. In this study, it was demonstrated that biodegradable PLGA microspheres coated with collagen type I and decorated with MnO2 nanoparticles acted as ROS scavengers controlling the H2O2-mediated apoptosis of cells undergoing oxidative stress. The results showed that the functionalized collagen spheres can protect cells even under very harsh conditions of oxidative stress.

Polylactides are extensively employed as bone-fixation devices, due to their degradability and high tensile modulus. As demonstrated in a previous study, the incorporation of barium sulfate submicron particles impressively enhanced toughness with almost no adverse effect on yield strength. It is therefore a promising strategy in the design of radiopaque materials intended for use in safety-critical systems. In the present study, the mechanism that causes high-level plastic deformation in this system is identified through tensile and fracture tests, together with a thorough analysis of the microstructure via transmission and SEM (Scanning Electron Microscopy). The presence of submicron particles was observed to reduce crystallinity and to increase energy dissipation during the plastic deformation of the polymer matrix, inducing crack widening and fibrillated crazing that propagated around the crack opening. The result is a five-fold increase in the energy that is required to fracture the composite with respect to its neat polymer counterpart.

Gd-Co/Ti multilayers were prepared by magnetron sputtering deposition onto glass substrates. The temperature dependence of magnetization of the multilayered structures depends on the Gd-Co layer thickness. It was shown that the obtained experimental results can be satisfactorily described in the framework of the joint application of models of the “size factor” and the “molecular field”. In addition, the possible effect of the electronic structure of titanium on the average magnetic moment of Co atoms, the efficiency of which depends on the thickness of the magnetic layers was also taken into account.

A family of cuspidine-type rare-earth (RE) aluminates with the general formula Ln4Al2O9 (Ln= Y, Sm, Eu, Gd, Tb) was prepared for potential use as thermal-barrier coating (TBC) materials with appropriate properties. Various trivalent lanthanides were applied to tailor the properties of the oxides for use as ceramic top coat (TC) materials intended for high-temperature applications. Following various heat treatments, the X-ray diffraction (XRD) results obtained demonstrated that Eu4Al2O9 (EuAM) possessed the greatest structural stability of all the samples at 1200 and 1300 °C. Moreover, Y4Al2O9 (YAM) had a long lifetime at 1000 °C, and was stable at 1100 °C. At 1200 °C, Sm4Al2O9 (SmAM) and Gd4Al2O9 (GdAM) were more stable than Tb4Al2O9 (TbAM). However, at 300–1000 °C, the TbAM exhibited the highest thermal expansion coefficient (TEC) of all the samples. At 600 °C, the thermal diffusivity values of the five compositions were favourable, and were lower than that of yttria-stabilised zirconia (YSZ) oxides.

Brown trout Salmo trutta alevins were maintained at 8 and 11° C at three conditions over a 9 day period from yolk sac exhaustion: fed ad libitum, starved or fed ad libitum after starvation. Whole-body gene expressions for proteins involved in energy metabolism and the two primary proteolytic pathways were assessed. This study is the first to show an over-expression of proteasome and autophagy-related genes in young stages of salmonids, particularly at 11° C.

Choosing materials for orthopedic implants often imposes strict requirements for the mechanical properties. Poly-L-lactide (PLLA) is widely employed for this purpose, however toughnening schemes are necessary for its suitable application. Blending of PLLA and biodegradable poly(L-lactide-co-ɛ-caprolactone) copolymer (PLCL) showing a thermoplastic-elastomeric behavior has been performed in an effort to toughen the PLLA without compromising its biodegradability and biocompatibility. The miscibility state of PLLA/PLCL blend system is studied by means of Differential Scanning Calorimetry (DSC) and Dynamic Mechanical Analysis (DMA). The mechanical properties will be also discussed, as well as, phase morphology observed by Scanning Electron Microscopy (SEM). Blends of PLLA/PLCL show different miscibility degrees depending on the blending process and the copolymer content. Blends prepared by melt-quenching show a miscibility window for compositions ≤30 wt% of PLCL, while a phase separation occurred in the rest of compositions. The toughness of PLLA was considerably improved by the addition of PLCL. The elongation at break was significantly increased.