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Parkinson's disease is the second most common neurodegenerative disease. Currently, there are no curative therapies, with only symptomatic treatment available. One of the principal reasons for the lack of treatments is the problem of delivering drugs to the brain, mainly due to the blood-brain barrier. Hydrogels are presented as ideal platforms for delivering treatments to the brain ranging from small molecules to cell replacement therapies.The potential application of hydrogel-based therapies for Parkinson's disease is addressed. The desirable composition and mechanical properties of these therapies for brain application are discussed, alongside the preclinical research available with hydrogels in Parkinson's disease. Lastly, translational and manufacturing challenges are presented.Parkinson's disease urgently needs novel therapies to delay its progression and for advanced stages, at which conventional therapies fail to control motor symptoms. Neurotrophic factor-loaded hydrogels with stem cells offer one of the most promising therapies. This approach may increase the striatal dopamine content while protecting and promoting the differentiation of stem cells although the generation of synapses between engrafted and host cells remains an issue to overcome. Other challenges to consider are related to the route of administration of hydrogels and their large-scale production, required to accelerate their translation toward the clinic.

The co-administration of glial cell line-derived neurotrophic factor (GDNF) and mesenchymal stem cells (MSCs) in hydrogels (HGs) has emerged as a powerful strategy to enhance the efficient integration of transplanted cells in Parkinson's disease (PD). This strategy could be improved by controlling the cellular microenvironment and biomolecule release and better mimicking the complex properties of the brain tissue. Here, we develop and characterize a drug delivery system for brain repair where MSCs and GDNF are included in a nanoparticle-modified supramolecular guest-host HA HG. In this system, the nanoparticles act as both carriers for the GDNF and active physical crosslinkers of the HG. The multifunctional HG is mechanically compatible with brain tissue and easily injectable. It also protects GDNF from degradation and achieves its controlled release over time. The cytocompatibility studies show that the developed biomaterial provides a friendly environment for MSCs and presents good compatibility with PC12 cells. Finally, using RNA-sequencing (RNA-seq), we investigated how the three-dimensional (3D) environment, provided by the nanostructured HG, impacted the encapsulated cells. The transcriptome analysis supports the beneficial effect of including MSCs in the nanoreinforced HG. An enhancement in the anti-inflammatory effect of MSCs was observed, as well as a differentiation of the MSCs toward a neuron-like cell type. In summary, the suitable strength, excellent self-healing properties, good biocompatibility, and ability to boost MSC regenerative potential make this nanoreinforced HG a good candidate for drug and cell administration to the brain.

Rivers are important contributors to the global carbon cycle as they actively transform terrestrial organic matter (OM) during transport to the oceans. The efficient OM processing results from a diverse assemblage of consumers including heterotrophic microbes (i.e., fungi, bacteria and protists) and macroinvertebrates, which interact with an equally diverse pool of OM. Ecologically, OM can be understood as forming a multidimensional resource space for consumers, whose understanding, however, requires an advanced capability to describe relevant dimensions (i.e., traits of OM) at a level that matches the resolution of consumer diversity, where significant advancement is generated by molecular biological means (i.e., DNA sequencing). This implies moving beyond proxy-based indirect descriptors (e.g., indices derived from absorbance or fluorescence spectroscopic analyses), integrative bulk property measures (e.g., C, N, P, lignin, tannins and fibre content) or bulk amounts of operational size fractions (e.g., dissolved, fine and coarse particulate OM). Recent technological advances such as size-exclusion, liquid or ion chromatography coupled to mass spectrometry have allowed to describe dissolved OM (DOM) on a molecular species level, setting a great step forward in the highly resolved description of DOM properties. However, particulate OM (POM) characterization remains behind significantly. Here, a per-particle basis description with regard to physical features and macromolecular composition is needed. We propose a procedure to asses both physical and chemical molecular properties of individual POM particles by combining (i) photometrical techniques, which are based on image processing and particle analysis (e.g., ImageJ) of pictures obtained with microscopes or cameras, and (ii) attenuated total reflectance infrared spectroscopy (ATR-FTIR) to measure particle-specific chemical composition. We apply this method to POM samples collected along large-scale environmental gradients in river networks.

Catchment urbanisation results in urban streams being exposed to a multitude of stressors. Notably, stressors originating from diffuse sources have received less attention than stressors originating from point sources. Here, advances related to diffuse urban stressors and their consequences for stream benthic communities are summarised by reviewing 92 articles. Based on the search criteria, the number of articles dealing with diffuse urban stressors in streams has been increasing, and most of them focused on North America, Europe, and China. Land use was the most common measure used to characterize diffuse stressor sources in urban streams (70.7 % of the articles characterised land use), and chemical stressors (inorganic nutrients, xenobiotics, metals, and water properties, including pH and conductivity) were more frequently reported than physical or biological stressors. A total of 53.3 % of the articles addressed the impact of urban stressors on macroinvertebrates, while 35.9 % focused on bacteria, 9.8 % on fungi, and 8.7 % on algae. Regarding ecosystem functions, almost half of the articles (43.5 %) addressed changes in community dynamics, 40.3 % addressed organic matter decomposition, and 33.9 % addressed nutrient cycling. When comparing urban and non-urban streams, the reviewed studies suggest that urbanisation negatively impacts the diversity of benthic organisms, leading to shifts in community composition. These changes imply functional degradation of streams. The results of the present review summarise the knowledge gained to date and identify its main gaps to help improve our understanding of urban streams.

International audience; Intermittent rivers and ephemeral streams (hereafter IRES) are waterways that temporarily cease to flow and/or dry up. They represent half the length of the global river network and are expanding in time and space in response to global change. The hydrological regimes of IRES are characterized by alternating flowing, non-flowing and dry phases, which translate to varying importance of in-stream litter accumulation, processing and downstream transport. Decomposition agents, processes and rates dramatically change among these hydrological phases, leading to decomposition dynamics that differ markedly from perennial rivers and streams. As a result, IRES have a specific “biogeochemical heartbeat” characterized by high temporal and spatial variability of leaf decomposition, and so they can be idealized as pulsed bioreactors. The ecological effects of flow cessation and drying are sometimes visible far beyond rewetting, generating “legacy effects” that become apparent even during later flowing phases. Rewetting events can represent “hot moments” of litter decomposition due to the intense biological and physical activities, generating pulses of transport and decomposition. Upscaling the abundant reach-scale knowledge to larger river-network scales is probably one of the most challenging but timely paths for future research.

Este artículo contiene 16 páginas, 5 figuras, 2 tablas., Leaf litter can be retained in floodplains for several months before it enters rivers as lateral inputs. During this period, the environmental conditions on the floodplain can alter leaf litter chemistry and, consequently, affect its subsequent processing in the river. We analysed the effect of contrasting floodplain conditions on the chemical composition of leaf litter and its leachates, and how this affected their biodegradability and processing in rivers. To do so, we placed reed leaf litter (Phragmites australis) in open- and closed-canopy habitats of three floodplain sites with contrasting climates (semiarid Mediterranean, humid Mediterranean and continental) for 105 days. We then used litterbags in a river to examine the decomposition of preconditioned leaf litter in comparison with a control (nonpreconditioned litter), and laboratory assays to examine the biodegradation of their leachates. Contrasting conditions on the floodplain prompted differences in the nutrient content of leaf litter among floodplain sites. Preconditioning caused a generalized decline in the C content and an increase in the lignin content of leaf litter. Even so, preconditioning did not affect litter decomposition rates in the river, although it did reduce decomposition efficiency and biodegradability of leachates. Shredder colonization of litter was variable and generally higher on preconditioned litter, but not significantly so. Different floodplain conditions had no influence on the aquatic processing of preconditioned litter. Our results demonstrate that the retention of leaf litter in terrestrial environments can affect C budgets of fluvial ecosystems and the recipient food web by reducing the input and the biodegradability of C and nutrients., This research was funded by Project 19525/PI/14 from the Seneca Foundation, Agency for Science and Technology, in Regio ´n de Murcia. R. del Campo was funded by a PhD contract (FPU R-269/2014) from the University of Murcia. E. Bastias was funded by a PhD contract (FPI) from the Spanish Ministry of Science and Innovation through the MEDFORESTREAM project (CGL2011-30590-C02-02). M.M. Sa ´nchez-Montoya was financially supported by a Marie-Curie postdoctoral fellowship (330466; MC-IEF; FP7people-2012-IEF).

Este artículo contiene 13 páginas, 4 figuras, 2 tablas., Intermittent rivers and ephemeral streams (IRES) encompass fluvial ecosystems that eventually stop flowing and run dry at some point in space and time. During the dry phase, channels of IRES consist mainly of dry riverbeds (DRBs), prevalent yet widely unexplored ecotones between dry and wet phases that can strongly influence the biogeochemistry of fluvial networks. DRBs are often overlooked because they do not strictly belong to either domain of soil or freshwater science. Due to this dual character of DRBs, we suggest that concepts and knowledge from soil science can be used to expand the understanding of IRES biogeochemistry. Based on this idea, we propose that DRBs can be conceptually understood as early stage soils exhibiting many similarities with soils through two main forces: i) time since last sediment transport event, and ii) the development status of stabilizing structures (e.g. soil crusts and/or vascular plants). Our analysis suggests that while DRBs and soils may differ in master physical attributes (e.g. soil horizons vs fluvial sedimentary facies), they become rapidly comparable in terms of microbial communities and biogeochemical processes. We further propose that drivers of DRBs biogeochemistry are similar to those of soils and, hence, concepts and methods used in soil science are transferable to DRBs research. Finally, our paper presents future research directions to advance the knowledge of DRBs and to understand their role in the biogeochemistry of intermittent fluvial networks., This paper resulted from discussions conducted as part of working group 3 “Coupled Aquatic-terrestrial Biogeochemistry in IRES” based upon work from COST Action CA15113 (SMIRES, Science and Management of Intermittent rivers and Ephemeral streams; www. smires.eu) supported by COST (European Cooperation in Science and Technology). Additional support was provided for MIA by an Alexander von Humboldt Grant (Ref: 1162886) and a Juan de la Cierva Grant (Ref: FJCI-2015-26192), for CM-L by an Early Career Fellowship from the Graduate Research School (GRS) at BTU Cottbus-Senftenberg and by the French Agency for Biodiversity (ONEMA-AFB, Action 13, Colmatage, échange snappe-rivière et processus biogéochimiques), for MA by the Spanish Government (Ref: DISECO CGL-2014-55-405-R) and by a Juan de la Cierva Grant (Ref: IJCI-2015-23500), for NC by a Juan de la Cierva Grant (Ref: FJCI-2014-23064), for SB by Spanish Government (Ref: NICUS CGL-2014-55234-JIN), for RG by the Science and Technology Agency of Murcia Region (SENECA Foundation, Ref: 19525/PI/14), for OS by the SMART joint Doctorate Programme (Science for the MAnagement of Rivers and their Tidal systems, funded by the Erasmus Mundus programme of the European Union) and for Fig. 4. Conceptual framework indicating the degree of similarity in three dimensions of dry riverbeds (DRBs): physical structure, microbial community and biogeochemistry, with soils as a function of two main drivers: (T) time since the last sediment transport event, and (S) development status of stabilizing structures (e.g. biocrusts and/or vascular plants). M.I. Arce et al. Earth-Science Reviews 188 (2019) 441–453 449 DvS by the Spanish Government (Ref: CGL2016-77487-R) and Basque Government (Ref: IT951-16). Symbols for diagrams used in the art work are courtesy of the Integration and Application Network (ian.umces. edu/symbols).

Ponencia presentada en: VI Simposio Nacional de Predicción, celebrado en los servicios centrales de AEMET, en Madrid, del 17 al 19 de septiembre de 2018. En esta ponencia proponemos una mirada sobre nuestros productos y nuestro léxico desde el punto de vista de la utilidad y la comprensibilidad para el usuario. Es decir, queremos hacer una revisión de la forma, más que del contenido, de nuestras predicciones; nos fijaremos en algunos de los productos o conceptos que más habitualmente suscitan dudas, controversias o gran expectación; pondremos algunos ejemplos de cómo manejamos en los medios y las redes sociales estas cuestiones, y haremos algunas propuestas para mejorar la comprensión de nuestras predicciones.

Climate change and human pressures are changing the global distribution and the extent of intermittent rivers and ephemeral streams (IRES), which comprise half of the global river network area. IRES are characterized by periods of flow cessation, during which channel substrates accumulate and undergo physico‐chemical changes (preconditioning), and periods of flow resumption, when these substrates are rewetted and release pulses of dissolved nutrients and organic matter (OM). However, there are no estimates of the amounts and quality of leached substances, nor is there information on the underlying environmental constraints operating at the global scale. We experimentally simulated, under standard laboratory conditions, rewetting of leaves, riverbed sediments, and epilithic biofilms collected during the dry phase across 205 IRES from five major climate zones. We determined the amounts and qualitative characteristics of the leached nutrients and OM, and estimated their areal fluxes from riverbeds. In addition, we evaluated the variance in leachate characteristics in relation to selected environmental variables and substrate characteristics. We found that sediments, due to their large quantities within riverbeds, contribute most to the overall flux of dissolved substances during rewetting events (56%–98%), and that flux rates distinctly differ among climate zones. Dissolved organic carbon, phenolics, and nitrate contributed most to the areal fluxes. The largest amounts of leached substances were found in the continental climate zone, coinciding with the lowest potential bioavailability of the leached OM. The opposite pattern was found in the arid zone. Environmental variables expected to be modified under climate change (i.e. potential evapotranspiration, aridity, dry period duration, land use) were correlated with the amount of leached substances, with the strongest relationship found for sediments. These results show that the role of IRES should be accounted for in global biogeochemical cycles, especially because prevalence of IRES will increase due to increasing severity of drying events., In this study we experimentally simulated under laboratory conditions rewetting of leaves, riverbed sediments, and epilithic biofilms collected during the dry phase from intermittent rivers and ephemeral streams covering global spatial scale. We determined the amounts and quality of the leached nutrients and dissolved organic matter, assessed their inter‐substrate and cross‐climate differences, and estimated areal fluxes from 1 m2 of riverbeds. In addition, we evaluated the variance in leachate characteristics related to selected environmental variables and substrate characteristics.

Ponencia presentada en: VI Simposio Nacional de Predicción, celebrado en los servicios centrales de AEMET, en Madrid, del 17 al 19 de septiembre de 2018. En este trabajo se analiza el efecto en la difusión de la información meteorológica del nombramiento de las borrascas, analizando los accesos a la página web de AEMET y la difusión a través de redes sociales de la información emitida por la Agencia, en una temporada que ha sido especialmente activa en nuestras latitudes debido a un patrón de NAO negativa.

Saline streams occur naturally and they are distributed worldwide, particularly in arid and semiarid regions, but human activities have also increased their number in many parts of the world. Little attention has been paid to assess increasing salt effects on organic matter decomposition. The objectives of this study were to analyse wood breakdown rates and how salinity affects them in 14 streams that exemplify a natural salinity gradient. We also analysed the effect of this gradient on changes in wood chemical composition, fungal biomass and microbial activity. Our results showed low breakdown rates (0.0010-0.0032 d(-1)), but they fell within the same range as those reported in freshwater streams when a similar woody substrate was used. However, salinity had a negative effect on the breakdown rates and fungal biomass along the salinity gradient, and led to noticeable changes in wood composition. Water salinity did not affect microbial activity estimated using hydrolysis of fluorescein diacetate. Variation in breakdown rates and fungal biomass across streams was mediated mainly by salinity, and later by stream discharge. Despite the role of fungi in stick breakdown, the potential wood abrasion by salts must be analysed in detail to accurately understand the effect of increasing salinity on organic matter breakdown. Finally, our results indicate that increased salinity worldwide by human activities or by the global warming would imply organic matter breakdown and mineralisation slowing down, even in natural saline streams. However, because many variables are implicated, the final effect of climatic change on organic matter decomposition in streams is difficult to predict.

Composite materials consisting of two dissimilar ferroic phases are an excellent alternative to single-phase multiferroics for a wide range of magnetoelectric technologies. In composites with strain-mediated magnetoelectric coupling the response is strongly dependent on the characteristics of the interface between the two mechanically coupled phases. Among the different material approaches considered, cofired ceramic composites offer improved reliability in applications and are more adequate for free-forming and miniaturization. However, their magnetoelectric response often suffers from poor reproducibility, which has been reiteratively associated with the quality of the interfaces with little experimental support. Here, we report an in-depth study of the local material properties across the interfaces of 0.36BiScO-0.64PbTiO/NiFeO multilayer ceramic composites, processed by spark plasma sintering of nanocrystalline powders. Tailored microstructures and low residual stress levels were obtained by adjusting the sintering mismatch between the two ferroic phases, which also resulted in fully functional interfaces and enhanced magnetoelectric responses., Authors are grateful to Prof. R. Moreno (ICV-CSIC, Madrid) for support in the tape-casting experiments and to Dr. M. Dollé (CEMES-CNRS/PNF2, Toulouse) for support in the SPS experiments. Local poling PFM experiments were carried out by Ms. C. Diéz. Technical support by Ms. I. Martiń ez and Ms. M. M. Antón is also acknowledged

espanolLos ecosistemas fluviales tienen un papel relevante en los ciclos biogeoquimicos globales, ya que procesan el material de la cuenca y lo transportan rio abajo. Sin embargo, los factores que afectan al metabolismo, especialmente aquellos que actuan en una escala espacial mas amplia, todavia no se conocen completamente. Ademas, el metabolismo fluvial puede variar a causa de cambios hidrologicos relacionados con la estacionalidad; lo que tambien hace importante incluir la variabilidad temporal para entender el funcionamiento de los rios. Mediante el uso de un experimento distribuido y coordinado, estudiamos diez rios de cabecera localizados a lo largo de cinco ecoregiones europeas durante verano y otono del 2014. Se midio la magnitud y la variabilidad de la produccion primaria bruta (PPB) y la respiracion ecosistemica (RE) mediante el metodo de canal abierto. Asi mismo, se examinaron los factores climaticos, hidrologico s y fisico-quimicos que potencialmente pueden afectar las tasas metabolicas fl uviales. Las tasas diarias de metabolismo fluvial variaron considerablemente entre rios, con valores de PPB de entre 0.06 a 4.33 g O2 m–2 dia–1, y de RE de entre 0.72 a 14.20 g O2 m–2 dia–1. Todos los rios fueron altamente heterotroficos (P/R EnglishStreams play a key role in the global biogeochemical cycles, processing material from adjacent terrestrial systems and transporting it downstream. However, the drivers of stream metabolism, especially those acting at broad spatial scales, are still not well understood. Moreover, stream metabolism can be affected by hydrological changes associated with seasonality, and thus, assessing the temporality of metabolic rates is a key question to understand stream function. This study aims to analyse the geographical and temporal patterns in stream metabolism and to identify the main drivers regulating the wholeecosystem metabolic rates at local and regional scales. Using a coordinated distributed experiment, we studied ten headwaters streams located across five European ecoregions during summer and fall 2014.We characterized the magnitude and variability of gross primary production (GPP) and ecosystem respiration (ER) with the open-channel method. Moreover, we examined several climatic, geographical, hydrological, morphological, and physicochemical variables that can potentially control stream metabolic rates. Daily rates of stream metabolism varied considerately across streams, with GPP and ER ranging from 0.06 to 4.33 g O2 m–2 d–1 and from 0.72 to 14.20 g O2 m–2 d–1, respectively. All streams were highly heterotrophic (P/R

In stream ecosystems, coarse organic matter from the riparian vegetation, a key food resource, is often retained in the floodplains before reaching the channel. During floodplain exposure, organic matter can be affected by abiotic and biotic processes ("preconditioning"), which alter its quality and affect its subsequent decomposition in streams. We analyzed the effect of floodplain preconditioning on wood quality (lignin, C, N, P, K, among others), and its subsequent aquatic breakdown, paying special attention to microbial activity. We simulated preconditioned standard wooden sticks on one arid stream floodplain for 3 and 4 months, and then monitored their breakdown in three different streams, together with control (non-preconditioned) sticks. Preconditioning reduced lignin mass and C:N and lignin:N ratios, caused the leaching of soluble nutrients such as P and K, as well as N immobilization by microbes. These changes enhanced the breakdown of wood in the first week of immersion, but had no effect on breakdown rates after 4 months of incubation in the streams, although N immobilization was diminished. Our results suggest that terrestrial preconditioning could alter the role of wood as a long-lasting nutrients and energy source for freshwater ecosystem.

© 2015 National Institute for Materials Science. A highly topical set of perovskite oxides are high-sensitivity piezoelectric ones, among which Pb(Zr,Ti)O3 at the morphotropic phase boundary (MPB) between ferroelectric rhombohedral and tetragonal polymorphic phases is reckoned a case study. Piezoelectric ceramics are used in a wide range of mature, electromechanical transduction technologies like piezoelectric sensors, actuators and ultrasound generation, to name only a few examples, and more recently for demonstrating novel applications like magnetoelectric composites. In this case, piezoelectric perovskites are combined with magnetostrictive materials to provide magnetoelectricity as a product property of the piezoelectricity and piezomagnetism of the component phases. Interfaces play a key issue, for they control the mechanical coupling between the piezoresponsive phases. We present here main results of our investigation on the suitability of the high sensitivity MPB piezoelectric perovskite BiScO3-PbTiO3 in combination with ferrimagnetic spinel oxides for magnetoelectric composites. Emphasis has been put on the processing at low temperature to control reactions and interdiffusion between the two oxides. The role of the grain size effects is extensively addressed., This work has been funded by the Spanish MINECO through projects MAT2011-23709 and AIB2010PT-00332. Collaboration between ICMM and CEMES is framed within the COST Action MP0904. Serviciencia S L (Spain) participation in the design and built-up of a novel magnetoelectric measurement system is acknowledged. HA thanks the Ramón y Cajal Programme for financial support.