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Este verano 2022 publicamos el informe "Radiografía del (des)empleo juvenil en España 2007 - 2022" convencidos de que, aunque se ha escrito mucho sobre empleo, sigue siendo una necesidad imperiosa analizar la situación de la empleabilidad juvenil, sus logros, retrocesos y enormes desafíos. Tras un periodo, además, que ha constatado de nuevo, tal y como se vio en España con la anterior crisis económica, la posición de fragilidad y vulnerabilidad de la población joven en el mercado de trabajo.En este estudio hemos querido recoger los principales datos y la evolución de los indicadores que reflejan los impactos en el empleo joven de las dos últimas crisis, así como la opinión de una mesa de expertos y expertas que ayudan a entender dichos datos y a trazar escenarios de futuro. &nbsp

El projecte que es presenta a continuació es basa en les recerques del grup IMEM (Innovació en Materials i Enginyeria Molecular) on es desenvolupen sensors multicapa composts per polímers conductors per a la detecció de neurotransmissors, amb la posterior aplicació en el sector de la biomedicina i/o bioenginyeria. La primera part del projecte es centra en determinar el procediment òptim de síntesi de la polianilina (PANI) mitjançant una tècnica electroquímica anomenada cronoamperometria (CA) i la seva posterior caracterització, tant de la seva morfologia com de les seves propietats elèctriques. També s’estudia la viabilitat d’aquest polímer en la detecció d’un neurotransmissor, la dopamina (DA). En segon lloc, es realitzen els mateixos estudis a la combinació de 3,4 – etilendioxitiofè (EDOT) i l’anilina (ANI) electrogenerats en dos medis diferents, aigua i acetonitril. A més, mitjançant tècniques de caracterització com ara, microscòpies i espectroscòpies, es determina si es produeix la copolimerització d’aquests dos monòmers en els medis de síntesis esmentats. En la tercera i última part, després d'obtenir un copolímer d'EDOT i ANI en medi aquós, s’elabora un sensor multicapa amb la següent estructura, alternant les tècniques de l'electropolimerització i el spin coating. - PLA nanoperforat, PEDOT-co-PANI, PLA nanoperforat, PEDOT-co-PANI, PLA nanoperforat. S'aplica el sensor obtingut en la detecció del neurotransmissor dopamina en dos medis, PBS i orina sintètica i, es comprova la seva viabilitat, tan dipositat sobre una placa d’acer com desprenent-ho d’ella, obtenint així un sensor free-standing. Finalment, es conclou que existeix copolimerització dels monòmers EDOT i ANI en medi aquós, però no en acetonitril. També es demostra que el sensor multicapa, format pel copolímer PEDOT-co-PANI en medi aquós com a material conductor, detecta la dopamina tant en PBS com en orina sintètica. El proyecto que se presenta a continuación se basa en las investigaciones del grupo IMEM (Innovació en Materials i Enginyeria Molecular) para desarrollar sensores multicapa compuestos por polímeros conductores para la detección de neurotransmisores, con la posterior aplicación en el sector de la biomedicina y/o bioingeniería. La primera parte del proyecto se centra en determinar el procedimiento óptimo de síntesis de la polianilina (PANI) mediante una técnica electroquímica llamada cronoamperometria (CA) y su posterior caracterización, tanto de su morfología como de sus propiedades eléctricas. También se estudia la viabilidad de este polímero en la detección de un neurotransmisor, la dopamina (DA). En segundo lugar, se realizan los mismos estudios a la combinación de 3,4 – etilendioxitiofeno (EDOT) y anilina (ANI) electrogenerados en dos medios distintos, agua y acetonitrilo. Además, mediante técnicas de caracterización tales como, microscopias y espectroscopias, se determina si se produce la copolimerización de estos dos monómeros en los medios de síntesis. En la tercera y última parte, tras obtener un copolímero de EDOT y ANI en medio acuoso, se elabora un sensor multicapa con la siguiente estructura, alternando las técnicas de la electropolimerización y el spin coating. - PLA nanoperforado, PEDOT-co-PANI, PLA nanoperforado, PEDOT-co-PANI, PLA nanoperforado. Se aplica el sensor obtenido en la detección del neurotransmisor dopamina en dos medios, PBS y orina sintética y, se comprueba su viabilidad, tanto depositado sobre una placa de acero como desprendiéndolo de ella, obteniendo así un sensor free-standing. Finalmente, se concluye que existe copolimerización de los monómeros EDOT y ANI en medio acuoso, pero no en acetonitrilo. También se demuestra que el sensor multicapa con copolímero PEDOT-co-PANI en medio acuoso como material conductor detecta la dopamina, tanto en PBS como en orina sintética. The project presented below is based on research by IMEM (Innovation in Materials and Molecular Engineering) which develops multilayer sensors composed of conductive polymers for the detection of neurotransmitters, with subsequent application in the biomedical and/or bioengineering sector. The first part of the project focuses on determining the optimal polyaniline (PANI) synthesis procedure using an electrochemical technique called chronoamperometry (CA) and its subsequent characterization, both of its morphology and its electrical properties. The viability of this polymer is also studied in neurotransmitter detection such as dopamine (DA). Secondly, the same studies are carried out in the combination of 3,4-ethylenedioxythiophene (EDOT) and aniline (ANI) electropolymerized using two different solvents, water and acetonitrile. In addition, by characterization techniques such as microscopes and spectroscopies, it is determined whether the copolymerization of these two monomers occurs in the synthesis media mentioned. In the third and final part, after obtaining a copolymer of EDOT and ANI in aqueous solution, a multilayer sensor is made with the following structure, alternating two techniques, electropolymerization and spin coating. - Nanoperforated PLA, PEDOT-co-PANI, nanoperforated PLA, PEDOT-co-PANI, nanoperforated PLA. The sensor obtained used for the detection of the neurotransmitter dopamine in a solution of PBS and synthetic urine, deposited on a steel plate and detaching it from it, obtaining a free-standing sensor. Finally, it is concluded that there is copolymerization of EDOT and ANI monomers in aqueous solution, but not in acetonitrile. It is also shown that the multilayer sensor, formed by the copolymer PEDOT-co-PANI in aqueous solution as conductive material, detects dopamine in PBS and synthetic urine.

This paper investigates the initiation of a deflagration in a premixed boundary-layer stream by continuous heat deposition from a line energy source placed perpendicular to the flow on the wall surface, a planar flow configuration relevant for small-scale combustion applications, including portable rotary engines. Ignition is investigated in the constant density approximation with a one-step irreversible reaction with large activation energy adopted for the chemistry description. The ratio of the characteristic strain time, given by the inverse of the wall velocity gradient, to the characteristic deflagration residence time defines the relevant controlling Damkhler number D. The time-dependent evolution following the activation of the heat source is obtained by numerical integration of the energy and fuel conservation equations. For sufficiently small values of D, the solution evolves towards a steady flow in which the chemical reaction remains confined to a finite nearsource reactive kernel. This becomes increasingly slender for increasing values of D, corresponding to smaller near-wall velocities, until a critical value D(c)1 is reached at which the confined kernel is replaced by a steady anchored deflagration, assisted by the source heating rate, which develops indefinitely downstream. As the boundary-layer velocity gradient is further decreased, a second critical Damkhler number D-c2 > D-c1 is reached at which the energy deposition results in a flashback deflagration propagating upstream against the incoming flow along the base of the boundary layer. The computations investigate the dependence of D-c1 and D-c2 on the fuel diffusivity and the dependence of D(c 1)on the source heating rate, delineating the boundaries that define the relevant regime diagram for these combustion systems. This work was supported by the Spanish MCINN through projects #CSD2010-00011, ENE2012-33213 and ENE2015-65852-C2-1-R.

An experimental study of methane, propane and dimethyl ether (DME) premixed flames propagating in a quasi-two-dimensional Hele-Shaw cell placed horizontally is presented in this paper. The flames are ignited at the open end of the combustion chamber and propagate towards the closed end. Our experiments revealed two distinct propagation regimes depending on the equivalence ratio of the mixture as a consequence of the coupling between the heat-release rate and the acoustic waves. The primary acoustic instability induces a small-amplitude, of around 8 mm, oscillatory motion across the chamber that is observed for lean propane, lean DME, and rich methane flames. Eventually, a secondary acoustic instability emerges for sufficiently rich (lean) propane and DME (methane) flames, inducing large-amplitude oscillations in the direction of propagation of the flame. The amplitude of these oscillations can be as large as 30 mm and drastically changes the outline of the flame. The front then forms pulsating finger-shaped structures that characterize the flame propagation under the secondary acoustic instability. The experimental setup allows the recording of the flame propagation from two different points of view. The top view is used to obtain accurate quantitative information about the flame propagation, while the lateral view offered a novel three dimensional perspective of the flame that gives relevant information on the transition between the two oscillatory regimes. The influence of the geometry of the Hele-Shaw cell and of the equivalence ratio on the transition between the two acoustic-instability regimes is analyzed. In particular, we find that the transition to the secondary instability occurs for values of the equivalence ratio ϕ above (below) a critical value ϕc for propane and DME (methane) flames. In all the tested fuels, the transition to the secondary instability emerges for values of the Markstein number M below a critical value M c . The critical Markstein number varies with the gap size h formed by the two horizontal plates that bound the Hele-Shaw cell. As h is reduced, the critical Markstein number is shifted towards larger values.

A method for computing minimum ignition energies for gaseous fuel mixtures with detailed and reduced chemistry, by numerical integration of time-dependent conservation equations in a spherically symmetrical configuration, is presented and discussed, testing its general characteristics and accuracy. The method is applied to methanol-air mixtures described by a 38-step Arrhenius chemistry description and by an 8-step chemistry description based on steady-state approximations for reaction intermediaries. Comparisons of predictions with results of available experimental measurements produced reasonable agreements and supported both the robustness of the computational method and the usefulness of the 8-step reduction in achieving accurate predictions. This work was supported by the Spanish MCINN through Projects # CSD2010-00011, ENE2012-33213 and ENE2015-65852-C2-1-R.

Antecedentes: El líquido sinovial es un compuesto biológico complejo que interviene en la lubricación, nutrición y la estructura de la mayoría de las articulaciones móviles. La patología asociada al derrame articular es muy variada y multifactorial. Sin embargo, el abordaje del derrame articular difiere si tiene su origen en un trauma o intervención quirúrgica, o si se origina por un proceso degenerativo o inflamatorio. Métodos: Se realizaron búsquedas con palabras clave apropiadas en las bases de datos de MEDLINE (PubMed), Scopus, SciELO y PEDro. Los estudios elegibles se seleccionaron sobre la base de varios criterios de inclusión y exclusión, además de abarcar la última década. Resultados: Se encontraron 4 estudios adecuados para esta revisión que, en conjunto, incluyen un total de 156 participantes humanos. Conclusión: Aunque la calidad metodológica de los estudios es baja, sugerimos que el drenaje linfático ayudaría a mejorar la reabsorción sinovial. Además, el abordaje farmacológico podría también fomentar la reabsorción mediante la creación de vías linfáticas. Background: Synovial fluid is a complex biological compound involved in the lubrication, nutrition and structure of most mobile joints. The pathology associated with joint effusion is very varied and multifactorial. However, joint effusion due to trauma or following surgery is tackled differently than degenerative or inflammatory episodes. Methods: Searches were performed using appropriate keywords on MEDLINE (PubMed), Scopus, SciELO and PEDro databases. Studies were selected based on several inclusion and exclusion criteria, as well as covering the last decade. Results: We found 4 studies suitable for this review. In sum, a total of 156 human participants were included. Conclusion: Although the methodological quality of the studies are low, we suggest that lymphatic drainage as well as specific drugs could help to improve synovial resorption.

There have been many experimental investigations into the ability of electric fields to enhance combustion by acting upon ion species present in flames. In this work, we examine this phenomenon using a one-dimensional model of a lean premixed flame under the influence of a longitudinal electric field. We expand upon prior two-step chain-branching reaction laminar models with reactions to model the creation and consumption of both a positively-charged radical species and free electrons. Also included are the electromotive force in the conservation equation for ion species and the electrostatic form of the Maxwell equations in order to resolve ion transport by externally applied and internally induced electric fields. The numerical solution of these equations allows us to compute changes in flame speed due to electric fields. Further, the variation of key kinetic and transport parameters modifies the electrical sensitivity of the flame. From changes in flame speed and reactant profiles we are able to gain novel, valuable insight into how and why combustion can be controlled by electric fields. This collaborative research was supported by the Spanish MCINN under Project #ENE2012–33213 and by King Abdullah University of Science and Technology (KAUST), Cooperative Agreement # 025478 entitled, electromagnetically Enhanced Combustion: Electric Flames. Publicado

PurposeIn this article, the authors analyse a complex social process affecting historic public paths in rural areas in southern Spain. Despite the fact that urban populations are demanding the enhancement of this type of natural heritage for tourism, sports and recreational use, some parts of the network have been abandoned or usurped.Design/methodology/approachThe study is multidisciplinary, comprising three interlinked studies. The cartographic study comprises an inventory of public paths in rural areas based on administrative sources. The legal study analyses local, regional and national regulations governing agricultural, environmental, heritage, sports and tourism uses of the infrastructure. The sociological study analyses social discourses on the uses of public paths, and identifies conflicts between farmers, landowners, environmentalists, sportspeople and tourists.FindingsThe preliminary results identified an important public paths network in Andalusia, approximately 160,000 km. The legal study found that there are laws regulating use, although local authorities do not monitor compliance or provide solutions to enhance management. The sociological study determined the attribution of environmental, cultural and economic value to public paths, but also the existence of conflicts between rural and urban populations.Research limitations/implicationsGiven that this is ongoing research, only state of the art and some preliminary albeit sufficiently consistent results are presented.Practical implicationsThe results could help to guide public policy and governance of public paths.Social implicationsPublic paths promote rural development and a green/sustainable economy.Originality/valueThe research results and conclusions are original.

We present a mathematical model to study the steady-state performance of a membrane-less reversibleredox flow batteryformed by two immiscible electrolytes that spontaneously form a liquid-liquid system separated by a well defined interface. The model assumes a two-dimensional battery with two coflowing electrolytes and flat electrodes at the channel walls. In this configuration, the analysis of the far downstream solution indicates that the interface remains stable in all the parameter range covered by this study. To simplify the description of the problem, we use the dilute solution theory to decouple the calculation of the velocity and species concentration fields. Once thevelocity fieldis known, we obtain the distribution of the mobile ionic species along with the current and the electric potential field of the flowing electrolyte solution. The numerical integration of the problem provides the variation of the battery current densityIappwith the State of Charge (SoC) for different appliedcell voltagesVcell. A detailed analysis of the concentration density plots indicates that the normal operation of the battery is interrupted when reactant depletion is achieved near thenegative electrodeboth during charge and discharge. The effect of the electrolyte flow on the performance of the system is studied by varying the Reynolds,Re, and Péclet,Pe, numbers. As expected, the flow velocity only affects thepolarization curvein theconcentration polarizationregion, whenVcellis well below theequilibrium potential, resulting inlimiting current densitiesthat grow withReasjlim∼Re0.3. In addition, both the single-pass conversion efficiencyψand the productψ jlimdecrease withRe. Concerning the later, the decay rate withReexhibits a power law with an exponent that almost doubles previous theoretical predictions obtained by imposing a prescribed velocity profile for the electrolyte in a membrane-lesslaminar flowbattery with a liquid oxidant and gaseous fuel. The present work constitutes the first modelling attempt that simultaneously solves the fluid dynamical system formed by the two immiscible electrolytes and the electrochemical problem that determines the response of the membrane-less battery. The proposed model could be used as a valuable tool to optimize future flow battery designs based on immiscible electrolytes.

The endocannabinoid system (ECS), a signalling network with immunomodulatory properties, is a potential therapeutic target in multiple sclerosis (MS). Dimethyl fumarate (DMF) is an approved drug for MS whose mechanism of action has not been fully elucidated; the possibility exists that its therapeutic effects could imply the ECS. With the aim of studying if DMF can modulate the ECS, the endocannabinoids 2-arachidonoylglycerol (2-AG), anandamide (AEA), oleoylethanolamide (OEA) and palmitoylethanolamide (PEA) were determined by liquid chromatography-mass spectrometry in peripheral blood mononuclear cells from 21 healthy donors (HD) and 32 MS patients at baseline and after 12 and 24 months of DMF treatment. MS patients presented lower levels of 2-AG and PEA compared to HD. 2-AG increased at 24 months, reaching HD levels. AEA and PEA remained stable at 12 and 24 months. OEA increased at 12 months and returned to initial levels at 24 months. Patients who achieved no evidence of disease activity (NEDA3) presented the same modulation over time as EDA3 patients. PEA was modulated differentially between females and males. Our results show that the ECS is dysregulated in MS patients. The increase in 2-AG and OEA during DMF treatment suggests a possible role of DMF in ECS modulation.