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Tacrolimus (FK506) is a macrolide lactone immunosuppressive drug that is commonly used in transplanted patients to avoid organ rejection. FK506 exhibits high inter- and intra-patient pharmacokinetic variability, making monitoring necessary for organ graft survival. This work describes the development of a novel bioassay for monitoring FK506. The bioassay is based on using polycaprolactone-based (PCL) magnetic Janus micromotors and a recombinant chimera receptor that incorporates the immunophilin tacrolimus binding protein 1A (FKBP1A) tagged with Emerald Green Fluorescent Protein (EmGFP). The approach relies on a fluorescence competitive bioassay between the drug and the micromotors decorated with a carboxylated FK506 toward the specific site of the fluorescent immunophilin. The proposed homogeneous assay could be performed in a single step without washing steps to separate the unbound receptor. The proposed approach fits the therapeutic requirements, showing a limit of detection of 0.8 ng/mL and a wide dynamic range of up to 90 ng/mL. Assay selectivity was evaluated by measuring the competitive inhibition curves with other immunosuppressive drugs usually co-administered with FK506. The magnetic propulsion mechanism allows for efficient operation in raw samples without damaging the biological binding receptor (FKBP1A-EmGFP). The enhanced target recognition and micromixing strategies hold considerable potential for FK506 monitoring in practical clinical use., UCM for a predoctoral contract, Depto. de Química Analítica, Fac. de Ciencias Químicas, TRUE, pub

Iron-doped TiO2 catalysts with two different iron contents (0.7 and 3.5 wt.%) as well as the corresponding undoped system, prepared by a combined sol–gel/microemulsion method and calcined at 600 °C, have been examined with respect to their behaviour for photocatalytic degradation of aqueous phenol with H2O2 under solar light. The activity results are complemented with structural/morphological and electronic characterization analysis achieved by XRD, TEM, Raman, SBET, UV–vis DRS and XPS techniques. A detrimental effect of the presence of iron on the photoactivity is detected for the sample with 0.7 wt.% iron. In contrast, some activity enhancement is produced for the sample with highest iron loading. Such irregular catalytic behaviour with respect to iron loading is analyzed on the basis of the presence of additional catalytic contributions from new photoactive species. These are created as a consequence of surface modifications produced under reaction conditions related to the existence of phenomena of iron leaching from the catalysts. Differences in the specific nanostructure present in each case can also play a role on explaining the differences observed in the photoactivity. Finally, an analysis of the photoactivity as a function of the oxidizing agent employed, either H2O2 or oxygen from air, is also performed., Ministerio de Educación y Ciencia, CSIC, Depto. de Química Inorgánica, Fac. de Ciencias Químicas, TRUE, pub

Authors wish to acknowledge the Ministry of the Environment (through project 136/PC08/3-11.2) for their financial support in this research., The hydrolysis process of bis-1,2-(triethoxysilyl)ethane (BTSE) was studied in aqueous and methanol solutions at pH 4. Nuclear magnetic resonance (NMR) evaluation of different solutions was carried out for 7 days. Unlike other researches, methanol-rich solutions are proven inadequate to reach a complete hydrolysis process. In water-rich solutions, hydrolysis takes place for 3 days, 85% of the silane molecules being transformed into silanols; this amount continues increasing up to the seventh day of hydrolysis., Ministry of Environment, Depto. de Ingeniería Química y de Materiales, Fac. de Ciencias Químicas, TRUE, pub

Financial support from the Fundación Universidad Carlos III de Madrid e Instituto Tecnológico de Química y Materiales “Álvaro Alonso Barba” is acknowledged. Authors also acknowledge Advanced Materials and Nanotechnology group (Mechanical Engineering Department, Universidad Pontifica Comillas-ICAI) for the possibility of performing the ATR-FTIR experiments and MINECO for the financial support to the project MAT2011-29182-C02-02., Polypropylene is one of the most used polymers due to its lightweight and recyclability properties, among others. However, its poor characteristics regarding surface energy and lack of polar functional groups have to be overcome to perform adhesion processes. The main objective of this work is to improve the adhesion behavior of polypropylene by combining atmospheric pressure plasma surface activation and silane adhesion promoter. Tetraethoxysilane hydrolysis and condensation are followed through infrared spectroscopy by attenuated total reflectance in order to set the coating conditions. Contact angle measurements and surface energy calculations as well as infrared and X-ray photoelectron spectroscopy are used to evaluate polymer chemical modifications. Morphological changes are studied through scanning electron and atomic force microscopy. Results show the ability of plasma treatment to create active oxydised functional groups on the polypropylene surface. These groups lead to a proper wetting of the polymer by the silane. Shear strength of single-lap bonding of polypropylene with a polyurethane adhesive suffers a significant improvement when the silane coating is applied on previously plasma activated samples. It has been also demonstrated that the silane curing conditions play a decisive role on the adhesion response. Finally, the stability of the silane solution is tested up to 30 days, yielding diminished but still acceptable adhesion strength values., Fundación Universidad Carlos III de Madrid, Instituto Tecnológico de Química y Materiales “Álvaro Alonso Barba”, Depto. de Ingeniería Química y de Materiales, Fac. de Ciencias Químicas, TRUE, pub

Atorvastatin is a potent lipid-lowering drug with poor solubility and high presystemic clearance that limits its therapeutic efficacy. The aim of this study was to develop solid dispersions and micellar systems to obtain fast -dissolving atorvastatin systems that enhances their anti-hyperlipidemic effect. Solubility and wettability studies allow the development of solid dispersions with low proportions of croscarmellose sodium as hydrophilic carrier. Solid state characterization studies indicated that the addition of Kolliphor (R) RH40 surfactant to solid dispersions increases intermolecular hydrogen bonding between drug and polymer chains. Dissolution studies in biorelevant Fasted State Simulate Intestinal Fluid (FaSSIF pH 6.5) medium showed for atorvastatin solid dispersion a su-persaturation peak of atorvastatin followed by an aggregation/precipitation process. Only the presence of a surfactant such as Kolliphor (R) RH40 in atorvastatin micellar system, promotes the presence of micelles that achieve delayed recrystallization. Efficacy studies were carried out using a hyperlipidemic model of rats fed with a high-fat diet. The atorvastatin micellar system at doses of 10 mg/kg, revealed a significant improvement in serum levels of total cholesterol, low-density lipoproteins, and triglycerides compared to atorvastatin raw ma-terial. This micellar system also exhibited more beneficial effects on liver steatosis, inflammation and ballooning injury., Universidad Complutense de Madrid, Ministerio de Ciencia e Innovación de España., Depto. de Farmacia Galénica y Tecnología Alimentaria, Fac. de Farmacia, TRUE, pub

This work reports the application of photocatalytic disinfection to the inactivation of Acanthamoeba trophozoites, a free-living pathogenic amoeba. Two types of photocatalytic reactors configurations have been used: i) a slurry reactor using suspended titanium dioxide (TiO2); and, ii) a fixed-bed reactor using immobilized TiO2 onto glass Raschig rings. The effect of the chemical composition of water has been analysed, comparing the efficiency of the process in deionized water (DW) and synthetic wastewater treatment plant effluent (SWTPE). The inactivation of Acanthamoeba spp. has been compared to that of Escherichia coli bacteria, being also analysed the concomitant inactivation of both microorganisms. Our results show that 99% of inactivation of E. coli and Acanthamoeba spp. can be achieved using photocatalysis in both reactor configurations, but interestingly, the kinetics of inactivation of both microorganisms together differs from that found with them separately. Particularly, E. coli seems to be more resistant to the inactivation in the presence of Acanthamoeba spp. which has been justified by the screen effect caused by the bigger size of Acanthamoeba spp. This observation is more pronounced in DW as the composition of the SWTPE prevent the microorganisms from suffering osmotic and/or mechanical stress and protect cellular structures to the attack of reactive oxygen species (ROS). On the other hand, the difference between the inactivation rate of E. coli and Acanthamoeba, points out the importance of the different inactivation mechanisms, suggesting that the entry of small TiO2 particles into the cytoplasm of the Acanthamoeba cells provokes the attack of inner structures and as a consequence a faster inactivation. This mechanism is not possible when the catalyst is immobilized leading to a higher cell resistance to inactivation and consequently lower efficiency of the disinfection process., Spanish State Research 536 Agency (AEI), Spanish Ministry of Economy and Competitiveness (MINECO), Comunidad de Madrid, Fundación Universitaria San Pablo CEU, Instituto de Salud Carlos III, Depto. de Química Inorgánica, Fac. de Ciencias Químicas, TRUE, pub

Hybrid photocatalysis/membrane processes constitute promising alternatives for water and wastewater treatment because they combine the efficiencies of filtration membranes technology and the oxidative effect of the photocatalytic process, increasing the lifetime of the membranes. The main challenge of these systems is the incorporation of the titanium dioxide (TiO2) catalyst without altering the filtration properties of the membrane and the photocatalytic activity of the catalyst. One way to achieve this goal is generating the TiO2 layer by direct anodization of titanium supports under controlled conditions to form titanium dioxide nanotubes (TiO2-NTs). This work reports the development of novel photocatalytic titanium membranes based on the formation of TiO2-NT arrays by anodization under both potentiostatic and galvanostatic conditions, and the scaling-up of the most promising systems to operational membrane photoreactors. The results demonstrated that the galvanostatic method displays more controlled tuneability to obtain NTs formation than the potentiostatic method on porous surfaces. However, despite the formation of TiO2-NTs structures, the observed photocatalytic activity is lower than that exhibited by TiO2 nanoparticles deposited directly on the membrane, although in this case the transmembrane pressure is significantly higher, and therefore the operational pumping costs are greater. Synergistic effects of photocatalysis and microfiltration are clearly demonstrated in the application of the hybrid system to the removal of bacteria for water disinfection processes, showing a significant improvement in the inactivation of E. coli bacteria in water with respect to the bare membrane., Spanish Ministry of Economy and Competitiveness (MINECO), Comunidad de Madrid, Depto. de Química Inorgánica, Fac. de Ciencias Químicas, TRUE, pub

Polysaccharides from the brown seaweed Himanthalia elongata and the red one Gigartina pistillata have been extracted by sequential fractionation based on the solubility in water (F-H2O), hydrochloride acid (F-HCl) and potassium hydroxide (F-KOH), remaining a residue (RES). Their structures have been studied through Fourier- transform infrared spectroscopy (FTIR) and molecular weight by molecular exclusion (HPSEC). Sugar compo- sition and sulphate content were also determined. F-H2O and F-HCl from Himanthalia elongata were rich in fucoidans with an estimated Mw of 926 and 430 × 103 g/mol. Laminarans appeared in the mentioned fractions and possibly xylofucoglycuronans and xylomannans are in F-H2O. F-HCl was poorly fermented with low pro- duction of total short chain fatty acids (SCFA) and two poor or non-fermentable low-molecular weight poly- uronans (68 and 4 × 103 g/mol) appeared in F-KOH. Carrageenans extracted from Gigartina pistillata presented low or non-fermentability. Xylofucoglycuronans and xylomannans, possibly presented in RES and F-H2O from Himathalia, and laminarans in the last mentioned fraction, seem to be more fermentable. Carragenophytes red seaweeds do not seem to be fermentable whereas brown algae could have major potential fermentability, probably due to the presence of laminarans, xylofucoglycuronans and/or xylomannans., Agencia Estatal de Investigación (FEDER, UE), Depto. de Nutrición y Ciencia de los Alimentos, Fac. de Farmacia, TRUE, pub

Phage display has become a powerful tool for antibody discovery in a wide variety of fields. This technology allows specific binders for a given antigen to be selected from combinatorial libraries. A key step in the process is characterizing and evaluating antibody clones thus selected to reliably identify the best antigen binders. Novel characterization methods can provide essential insight into the binding mechanism and supplement the information obtained with conventional techniques. In this work, we used a quartz crystal microbalance with dissipation monitoring (QCM-D) to determine the kinetic and thermodynamic binding parameters for phage-displayed VH antibody fragments. Phytohemagglutinin (PHA), a legume lectin of analytical interest, was used as a complex model antigen to select specific VH fragments from a phage-displayed library. Eight VH fragments with a unique amino acid sequence were identified as PHA binders by using the well-established enzyme-linked immunosorbent assay (ELISA). QCM-D measurements, structural analysis and principal component analysis (PCA) were used to evaluate the antibody fragments and identify clone clusters with similar binding characteristics and molecular interaction mechanisms. This unprecedented study has enabled the identification of high-affinity phage-displayed VH antibody fragments for PHA, which could be useful for PHA analysis (apparent association constant ranged from 10e8 to 10e10 1/M). In fact, the proposed methodology provides a useful tool for evaluating and characterizing antibody fragments with capabilities beyond those of conventional techniques., European Regional Development Fund (ERDF), Depto. de Química Analítica, Fac. de Ciencias Químicas, TRUE, pub

A series of Ni/Fe electrodes have been prepared by electrodeposition of metal salt precursors on different substrates. The surface morphology, chemical composition and electrochemical characteristics of these electrodes were studied by various physico-chemical techniques such as X-ray Photoelectron Spectroscopy (XPS) and Scanning Electron Microscopy (SEM). The electrochemical properties of the electrodes were examined by steady-state polarization curves. First, the influence of features such as Ni/Fe composition and type of substrate for the oxygen evolution reaction (OER) were determined by electrochemical techniques in a conventional 3-electrodes cell. The overpotential for the OER is lower for the electrodes with the higher concentrations of Ni. The electrodes with a Ni/Fe composition of 75/25 wt.% electrodeposited on steel mesh and/or 75/25 and 50/50 wt.% on nickel foam result in the most active configurations for the OER. These electrodes were further tested as anodes for alkaline water electrolysis during at least 70 h. In order to understand their activity and stability, the used electrodes were also characterized by SEM and compared to the fresh electrodes. Among the compositions and substrates examined, the Ni50Fe50-Nf electrode exhibited the lowest overpotential (2.1 V) for the OER and the higher stability as anode in an alkaline water electrolysis cell., Spanish Education and Science Ministry, CENIT-SPHERA, MICINN, Depto. de Química Inorgánica, Fac. de Ciencias Químicas, TRUE, pub

Due to the inherent low surface energy of the polymer matrix portion of a given composite material, poor adhesion properties are exhibited and must be overcome in order to achieve strong adhesive bonds. Mechanical methods to improve adhesion have typically included manual abrasion like sanding or grit blasting. Energetic techniques, such as laser and plasma, are garnering continued attention towards the same end. This work describes results of recent investigations of atmospheric pressure plasma treatment (APPT) of composite materials based on glass and carbon fiber reinforced toughened epoxy resin systems for adhesive bonding. Chemical, physical and APPT treatments were compared in terms of enhancing surface energy and interfacial fracture toughness. Surface treatments were followed by characterization of wetting properties using traditional contact angle techniques as well as ballistic liquid deposition. The effects of APPT on the substrates were characterized by taking into account both chemical and morphological changes. Attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) and X-ray photoelectron spectroscopy (XPS) were used to confirm the elimination of fluorine and the introduction of oxygen and nitrogen. Etching effects of plasma were studied by scanning electron microscopy (SEM) and atomic force microscopy (AFM). The double cantilever beam (DCB) test configuration was used to investigate treatment effects on adhesive bond performance. Results exhibited the effectiveness of physical procedures in cleaning surfaces, while APPT generated a higher hydrophilic behavior. All the samples tested by DCB yielded cohesive failure mode within the laminates., Depto. de Ingeniería Química y de Materiales, Fac. de Ciencias Químicas, TRUE, pub

2023 Acuerdos transformativos CRUE, Context: Chess engines are computer programs that analyse chess positions. The goal of this analysis is to decide which player has an advantage and evaluate how big the advantage is. Using this analysis, chess engines are really powerful players who can consistently beat the best (human) players. Even though these programs are fantastic players, we cannot be sure that the code is fault free because it is very difficult to test them. In particular, we face the oracle problem: if the chess engine plays better than any potential tester, how can a tester claim that a certain evaluation is wrong or that a suggested move is not the best one? Objective: The main goal of our work is to provide a metamorphic testing tool to evaluate chess engines. In particular, we are interested in looking for inconsistent behaviours in the best publicly available chess engine, Stockfish, but we would also like to consider other chess engines. Methods: We developed a metamorphic testing solution to validate chess engines. First, we defined metamorphic relations that might reveal inconsistent behaviours. The underlying idea was that the evaluation of related positions should be the same. For example, if we consider a position and rotate all the pieces with respect to the central axis, then both positions should have the same evaluation. One of our main priorities was to have a fully automatised tool. Source inputs are obtained from available datasets while follow-up inputs are automatically computed by applying sound transformations to the source inputs with respect to the corresponding metamorphic rule. In order to assess the usefulness of our work, we applied it to analyse a dataset with more than 40,000 positions. Results: Empirical evidence validates the usefulness of our work to analyse the best available chess engine, Stockfish. Our tool revealed non-negligible deviations from the expected behaviour in Stockfish for all the MRs. Additional experiments showed that our tool can be easily, Depto. de Sistemas Informáticos y Computación, Fac. de Informática, TRUE, pub, APC financiada por la UCM

Cognitive decline is one of the most important consequences of aging and pharmacological therapies had been largely unsuccessful. Other strategies include the use of functional foods to reduce the burden of cognitive decline. The MFGM is an important source of polar lipids and glycoproteins that decline in the aging brain. We have developed a milk drink fortified with MFGM (MFGM-M) as a dietary supplement and studied it in a randomized clinical pilot study. Forty-four > 65-year-old healthy or mildly cognitively impaired subjects received MFGM-M or control milk (CM) for 14 weeks, during which they underwent a battery of cognitive tests. Lipidomic analyzes were also performed. The female participants showed improvement in episodic memory, the ability to recall events in our lives. It is conceivable that any intervention should be started before clinical symptoms manifest, as a preventive measure against cognitive decline. Future long-term studies may shed further light on this point., Ministerio de Ciencia, Innovación y Universidades, Depto. de Nutrición y Ciencia de los Alimentos, Fac. de Farmacia, TRUE, pub, APC financiada por la UCM

2023 Acuerdos transformativos CRUE, In multiple applications, from Statistics to Particle Physics and notably in Cryptography and Computer Security, it is necessary to obtain long sequences of random numbers. In order to verify the properties of these sequences, different statistical tests are commonly applied, which are usually included in the so-called test batteries or test suites. The batteries need to be both effective and efficient. Their effectiveness relates to how well they can spot non-randomness behaviour, the efficiency is related to the computational time they require. It is therefore essential for tests included in batteries to measure their independence features: Test independence is important for good effectiveness, as high correlations between tests could lead to a decreased efficiency (testing for the same features multiple times) and effectiveness (missing an opportunity to test for an orthogonal randomness property when we essentially measure the same twice). Moreover, the related study of test coverage is often based on the assumption that tests are independent. This paper describes a series of experiments aimed at scrutinizing dependencies among the statistical tests in the NIST SP 800-22 suite. In order to do so, sequences of varying lengths from sources of varying entropy have been generated and tested. Afterwards, an inferential study was carried out to find whether significant correlations exist and to present our findings in a statistically sound way., Depto. de Ingeniería de Software e Inteligencia Artificial (ISIA), Fac. de Informática, TRUE, pub, APC financiada por la UCM

The preparation and study of new pure M0.90Eu0.1‐xDyxZr4(PO4)6 samples with M = Sr or Ba and x = 0, 0.025, 0.050 and 0.075 was described here in detail. Currently, the luminescent emission study of this type of samples based on their tunable with the type and content of ions in the host lattice is the subject of research. These samples were synthesized by a combustion route with urea addition, followed by treatment in a reducing N2/H2 atmosphere. The effect of the strontium by barium substitution and the europium by dysprosium partial substitution on the structure, powder morphology, luminescent emission and magnetic behavior was investigated by X-ray diffraction (XRD), transmission electron microscopy (TEM), photoluminescence (PL) spectroscopy and magnetic measurements. X-ray diffraction patterns of the pure samples show diffraction maxima that can be assigned to a rhombohedral symmetry of space group R-3 with Z=6, compatible with a NASICON-type structure. FTIR spectra of the investigated samples show a broad band assignable to the different vibrational modes of the PO4 3- groups. The experimental FTIR study was complemented with a theoretical study based on the SrZr4(PO4)6 structure and using different DFT methods and basis sets. Highly agglomerated spherical nanoparticles with an average particle size of about 18 nm that slightly increased with dysprosium content were found in TEM images. Broad emission bands were observed in the PL spectra of obtained samples, related to both the strontium by barium substitution and the different Eu2+/Eu3+/Dy3+ content. Magnetic susceptibility curves as a function of temperature confirm the presence of Eu2+ ions in Sr0.90Eu0.1Zr4(PO4)6 sample, and of Dy3+ ions with different Eu2+/Eu3+ ions content in the remaining M0.90Eu0.1‐xDyxZr4(PO4)6 samples., Fundación Neurociencias y Envejecimiento (España), Ministerio de Ciencia, Innovación y Universidades (España), Depto. de Química Inorgánica, Fac. de Ciencias Químicas, TRUE, pub

Producción Científica, One Shot Learning includes all those techniques that make it possible to classify images using a single image per category. One of its possible applications is the identification of food products. For a grocery store, it is interesting to record a single image of each product and be able to recognise it again from other images, such as photos taken by customers. Within deep learning, Siamese neural networks are able to verify whether two images belong to the same category or not. In this paper, a new Siamese network training technique, called CP-CVV, is presented. It uses the combination of different models trained with different classes. The separation of validation classes has been done in such a way that each of the combined models is different in order to avoid overfitting with respect to the validation. Unlike normal training, the test images belong to classes that have not previously been used in training, allowing the model to work on new categories, of which only one image exists. Different backbones have been evaluated in the Siamese composition, but also the integration of multiple models with different backbones. The results show that the model improves on previous works and allows the classification problem to be solved, an additional step towards the use of Siamese networks. To the best of our knowledge, there is no existing work that has proposed integrating Siamese neural networks using a class-based validation set separation technique so as to be better at generalising for unknown classes. Additionally, we have applied Cross-Validation-Voting with ConvNeXt to improve the existing classification results of a well-known Grocery Store Dataset., The Centre for the Development of Industrial Technology (CDTI) and by the Instituto para la Competitividad Empresarial de Castilla y León - FEDER (Project CCTT3/20/VA/0003)

Producción Científica, Neurofeedback (NF) is a paradigm that allows users to self-modulate patterns of brain activity. It is implemented with a closed-loop brain-computer interface (BCI) system that analyzes the user’s brain activity in real-time and provides continuous feedback. This paradigm is of great interest due to its potential as a non-pharmacological and non-invasive alternative to treat non-degenerative brain disorders. Nevertheless, currently available NF frameworks have several limitations, such as the lack of a wide variety of real-time analysis metrics or overly simple training scenarios that may negatively affect user performance. To overcome these limitations, this work proposes ITACA: a novel open-source framework for the design, implementation and evaluation of NF training paradigms., Ministerio de Ciencia e innovación, Agencia Estatal de Investigación y FEDER (PID2020-115468RB-I00, RTC2019-007350-1 y TED2021-129915B-I00)

Producción Científica, A new approach for the parallel computation of the Laplacian in the Fourier domain is presented. This numerical problem inherits the intrinsic sequencing involved in the calculation of any multidimensional Fast Fourier Transform (FFT) where blocking communications assure that its computation is strictly carried out dimension by dimension. Such data dependency vanishes when one considers the Laplacian as the sum of n independent one-dimensional kernels, so that computation and communication can be naturally overlapped with nonblocking communications. Overlapping is demonstrated to be responsible for the speedup figures we obtain when our approach is compared to state-of-the-art parallel multidimensional FFTs., Junta de Castilla León (grant number VA296P18)

Producción Científica, Background and objective. Neurotechnologies have great potential to transform our society in ways that are yet to be uncovered. The rate of development in this field has increased significantly in recent years, but there are still barriers that need to be overcome before bringing neurotechnologies to the general public. One of these barriers is the difficulty of performing experiments that require complex software, such as brain-computer interfaces (BCI) or cognitive neuroscience experiments. Current platforms have limitations in terms of functionality and flexibility to meet the needs of researchers, who often need to implement new experimentation settings. This work was aimed to propose a novel software ecosystem, called MEDUSA©, to overcome these limitations. Methods. We followed strict development practices to optimize MEDUSA© for research in BCI and cognitive neuroscience, making special emphasis in the modularity, flexibility and scalability of our solution. Moreover, it was implemented in Python, an open-source programming language that reduces the development cost by taking advantage from its high-level syntax and large number of community packages. Results. MEDUSA© provides a complete suite of signal processing functions, including several deep learning architectures or connectivity analysis, and ready-to-use BCI and neuroscience experiments, making it one of the most complete solutions nowadays. We also put special effort in providing tools to facilitate the development of custom experiments, which can be easily shared with the community through an app market available in our website to promote reproducibility. Conclusions. MEDUSA© is a novel software ecosystem for modern BCI and neurotechnology experimentation that provides state-of-the-art tools and encourages the participation of the community to make a difference for the progress of these fields. Visit the official website at https://www.medusabci.com/ to know more about this project., Ministerio de Ciencia e Innovación/Agencia Estatal de Investigación/10.13039/501100011033/' y el Fondo Europeo de Desarrollo Regional (FEDER) grants (PID2020-115468RB-I00 and RTC2019-007350-1)

1:1 Co-crystals of carbamazepine (CBZ) and saccharin (SAC) were obtained for the first time through the supercritical anti-solvent (SAS) technique based on using supercritical CO2 as anti-solvent. The capability of SAS to produce the desired polymorphic form (two polymorphs are known) was assessed. Operational conditions investigated were temperature (40.0 and 60.0 °C), pressure (10.0 and 15.0 MPa), solvent choice and coformer concentration in the organic solution (CBZ: 30 and 15 mg/mL; SAC: stoichiometric ratio). Co-crystals were characterized in terms of crystallinity and coformers interactions. No homocrystals were present. Using methanol, at 40.0 °C polymorph I was obtained with yields up to 65%; whilst at 60.0 °C a mixture of polymorphs was obtained. Mixtures of polymorphs were also obtained in the ethanol and dichloromethane experiments at the studied conditions while the dimethylsulfoxide experiments failed to produce any co-crystal polymorph. For comparison purposes, pure CBZ and SAC were also processed by SAS., Depto. de Química Física, Fac. de Ciencias Químicas, TRUE, pub

Nickel ferrite samples are currently investigated due to their potential technological applications. For this reason, the optimal synthesis conditions of nickel ferrite samples with small particle size were investigated here. First, a systematic study was carried out using urea as an additive, and varying reaction parameter such as the amount of urea added or the reaction temperature and time. For comparison purposes, another sample was synthesized using potassium hydroxide as an additive. The two pure nickel ferrite samples were coated with silica, functionalizing them with APTES and AEPMDS. X-rays, FTIR, Mössbauer spectroscopy, TEM and Ms vs. H and FC/ZFC curves were used for the characterization of samples and the evaluation of their properties. Square particles with an average size of 21.2 nm were observed in the TEM images of the sample synthesized with urea, while these are spherical of 6.2 nm in the sample prepared with potash. Their subsequent coating and functionalization give rise to an arrangement of particles within interlocking strands whose thickness increases with their size. Ms vs. H curves confirm the almost superparamagnetic behavior of all synthesized powders, although with a slight increase in the coercivity value of the samples prepared with urea. Preliminary tests carried out on the functionalized samples to evaluate the adsorption capacity in aqueous solution and their easy separation in presence of an external magnetic field, confirm that the sample syn thesized with urea and functionalized with AEPDMS is the most efficient for the Cu2+ ions removal., Fundación Neurociencias y Envejecimiento (España), Ministerio de Economía y Competitividad (España), Comunidad de Madrid, European Commission, Ministerio de Ciencia, Innovación y Universidades (España), Depto. de Química Inorgánica, Depto. de Química Física, Fac. de Ciencias Químicas, TRUE, pub

The preparation and study of new bifunctional (Y0.9Ln0.1VO4/Fe3O4)@SiO2 and [(Y0.9Ln0.1VO4@SiO2)/ Fe3O4@SiO2] samples with Ln = Nd or Tb is described in detail. The influence of Fe3O4 content and silica coating on Y0.9Ln0.1VO4@SiO2 samples is analyzed to decide on their potential utility. Materials of this type are currently of great interest in the biomedicine field based on their potential use as bifunctional materials. On the one hand, because they can be directed using an external magnetic field and, on the other, because they can allow the visualization of diseased cells after appropriate functionalization. Y0.9Ln0.1VO4 samples with Ln = Nd or Tb were prepared by a hydrothermal process, while Fe3O4 sample was prepared by the coprecipitation method. These samples and different mixtures of them were treated with tetraethyl orthosilicate (TEOS) to proceed with their silica coating. All diffraction maxima of Y0.9Ln0.1VO4 samples were indexed on a tetragonal symmetry of space group I41/amd, compatible with a zircon structure-type. In the case of Fe3O4 sample, all reflections were indexed to a cubic symmetry of space group Fd 3 m, characteristic of an inverse spinel structure-type. These results also agreed well with the FTIR spectra of the investigated samples. For the first time, the experimental FTIR study of Y0.9Ln0.1VO4 samples was complemented with a theoretical vibrational study based on the YVO4 structure. To carry out this theoretical study, different density functional theory (DFT) methods and different basis sets were used. Silica presence in samples was clearly verified in both, the XRD profiles and the FTIR spectra. Elongated and spherical particles are found in TEM images of these samples. The study of PL emission and magnetic behavior showed that [(Y0.9Ln0.1VO4@SiO2)/Fe3O4@SiO2] samples are the most suitable for use as bifunctional materials., Ministerio de Ciencia, Innovación y Universidades (España), Instituto de Salud Carlos III, Comunidad de Madrid, Universidad Autónoma de Madrid, Depto. de Química Inorgánica, Depto. de Química Física, Fac. de Ciencias Químicas, TRUE, pub

Producción Científica, In this work, we have studied the control of set and the reset transitions in TiN/Ti/HfO2/W resistive switching devices using a new approach based on the injection of a limited amount of charge through the use of a capacitor discharge. Instead of applying conventional voltage or current signals, the capacitor discharge through the devices is able to perform both transitions. An accumulative process is observed if we apply consecutive discharges, and, when increasing the capacitor voltage in each discharge, the transitions between both resistance states are completed. In addition, it has been shown that faster transitions require larger capacitor voltages. Further, the electrical results were used to tune the dynamic memdiode model, which was employed to simulate set and reset processes driven by the capacitor discharges. The model successfully reproduced the measured memristor response to the capacitor discharge., Ministerio de Ciencia, Innovación y Universidades y programa FEDER (proyectos TEC2017-84321-C4-1-R, TEC2017-84321-C4-2-R, TEC2017-84321-C4-3-R y TEC2017-84321-C4-4-R)

Producción Científica, Solving computational fluid dynamics problems requires using large computational resources. The computa- tional time and memory requirements to solve realistic problems vary from a few hours to several weeks with several processors working in parallel. Motivated by the need of reducing such large amount of resources (improving the industrial applications in which fluid dynamics plays a key role), this article introduces a new predictive Reduced Order Model (ROM) applied to solve fluid dynamics problems. The model is based on physical principles and combines modal decompositions with deep learning architectures. The hybrid ROM, reduces the dimensionality of a database via proper orthogonal decomposition (POD), extracting the dominant features leading the flow dynamics of the problem studied. The number of degrees of freedom are reduced from hundred thousands spatial points describing the database to a few (20–100) POD modes. Firstly, POD divides the spatio-temporal data into spatial modes and temporal coefficients (or temporal modes). Next, the temporal coefficients are integrated in time using convolutional or recurrent neural networks. The temporal evolution of the flow is approximated after combining the spatial modes with the new temporal coefficients computed. The model is tested in two complex problems of fluid dynamics, the three-dimensional wake of a circular cylinder and a synthetic jet. The hybrid ROM uses data from the initial transient stage of numerical simulations to predict the temporally converged solution of the flow with high accuracy. The speed-up factor comparing the time necessary to obtain the predicted solution using the hybrid ROM and the numerical solver is ∼140–348 in the synthetic jet and ∼2897–3818 in the three dimensional cylinder wake. The robustness shown in the results presented and the data-driven nature of this ROM, make it possible to extend its application to other fields (i.e. video and language processing, robotics, finances), Ministerio de Ciencia, Innovación y Universidades Proyectos de I+D+i ‘‘Retos investigación’’, (grant RTI2018-098958- B-I00), Ministerio de Ciencia e Innovación y el Fondo Europeo de Desarrollo Regionales (FEDER) (grant PID2020-114173RB-I00)

Producción Científica, In this work, we have studied the set and the reset transitions in hafnium oxide-based metal-insulator-metal ReRAM devices using a capacitor discharge. Instead of applying a conventional voltage or current signal, we have discharged a capacitor through the devices to perform both transitions. In this way, both transitions are shown to be controllable. An accumulative process is observed if we apply consecutive discharges, and, when increasing the capacitor voltage in each discharge, the transitions between both resistance states are complete. In addition, it has been shown that faster transitions require larger capacitor voltages., Ministerio de Economía y Competitividad y el programa FEDER (Grant, TEC2017-84321-C4-2-R y TEC2017-84321-C4-1-R)

Producción Científica, Resistive switching random access memories are being thoroughly studied as prospective non-volatile memories. In this paper, we report electrical characterization of HfO2:Al2O3based metal-insulator–metal structures devised using atomic layer deposition. Dependences of electrical behavior on HfO2:Al2O3 cycle ratio is studied. An explanation for the differences between the Resistive Switching properties of the samples is proposed, based on the distribution of HfAlOx layers of the sample. Dependence of the RS properties of the samples on their growth temperature is discussed., Ministerio de Ciencia, Innovación y Universidades con el apoyo de fondos Feder (grant TEC2017-84321-C4-2-R), Fondo Europeo de Desarrollo Regional "Pedidos emergentes en cuanto a cuántica y nanomateriales" (TK134), Estonian Research Agency (PRG753)

Producción Científica, The integral valorization of potential sugars (cellulosic and hemicellulosic) from spentcoffee grounds (SCG), a lignocellulosic residue, is proposed in this work. With this aim,the microwave assisted dilute sulfuric acid pretreatment has been optimized, leading toa hemicellulosic sugar recovery in the pretreatment liquid (HSR L ) and an enzymatichydrolysis yield of 79 and 98%, respectively, at 160.47 ºC and 1.5% H 2 SO 4 .Moreover, the complete digestibility of cellulose (enzymatic hydrolysis yield = 100%)was also discovered for non-pretreated SCG, which is very interesting. Secondly, theproduction of biobutanol, an advanced biofuel, is also proposed from pretreated SCGenzymatic hydrolysate and pretreatment liquid achieved under optimal conditions.These were fermented by Clostridium beijerinckii , yielding 95 kg butanol/t SCG (drymatter) and 151 kg acetone-butanol-ethanol/t SCG (dry matter)., junta de Castilla y Leon y EU-FEDER (VAG028G19, CLU 2017-09, UIC 129)

Producción Científica, Since two decades ago, research on resistive memories has continuosly grown, gathering relevance through the variety of different technologies that fit into the non-volatile memories’ area. In this study, we discuss the performance and electrical characteristics of RRAM cells constituted by MIM stacks with dielectric formed by Nb2O5-doped SiO2. We report experimental results that show a clear improvement in the resistive behavior of the devices and an excellent analogical control of the intermediate levels between high-resistance and low-resistance states., Ministerio de Ciencia, Innovación y Universidades con el apoyo de fondos Feder (grant TEC2017-84321-C4-2-R), Finnish Centre of Excellence in Atomic Layer Deposition (284623), Estonian Research Agency (PRG753)

Producción Científica, Three innovative operational strategies were successfully evaluated to improve the quality of biomethane in an outdoors pilot scale photobioreactor interconnected to an external absorption unit: i) the use of a greenhouse during winter conditions, ii) a direct CO2 stripping in the photobioreactor via air stripping during winter conditions and iii) the use of digestate as make-up water during summer conditions. CO2 concentrations in the biomethane ranged from 0.4% to 6.1% using the greenhouse, from 0.3% to 2.6% when air was injected in the photobioreactor and from 0.4% to 0.9% using digestate as make up water. H2S was completely removed under all strategies tested. On the other hand, CH4 concentrations in biomethane ranged from 89.5% to 98.2%, from 93.0% to 98.2% and from 96.3% to 97.9%, when implementing strategies i), ii) and iii), respectively. The greenhouse was capable of maintaining microalgae productivities of 7.5 g m−2 d−1 during continental weather conditions, while mechanical CO2 stripping increased the pH in order to support an effective CO2 and H2S removal. Finally, the high evaporation rates during summer conditions allowed maintaining high inorganic carbon concentrations in the cultivation broth using centrate, which provided a cost-effective biogas upgrading., Junta de Castilla y León y EU-FEDER (CLU 2017-09 y UIC 071)

Producción Científica, Indoor air pollution has traditionally received less attention than outdoors pollution despite indoors pollutant levels are typically twice higher, and people spend 80–90% of their life in increasing air-tight buildings. More than 5 million people die every year prematurely from illnesses attributable to poor indoor air quality, which also causes multi-millionaire losses due to reduced employee’s productivity, material damages and increased health system expenses. Indoor air pollutants include particulate matter, biological pollutants and over 400 different chemical organic and inorganic compounds, whose concentrations are governed by several outdoor and indoor factors. Prevention of pollutant is not always technically feasible, so the implementation of cost-effective active abatement units is required. Up to date no single physical-chemical technology is capable of coping with all indoor air pollutants in a cost-effective manner. This problem requires the use of sequential technology configurations at the expenses of superior capital and operating costs. In addition, the performance of conventional physical-chemical technologies is still limited by the low concentrations, the diversity and the variability of pollutants in indoor environments. In this context, biotechnologies have emerged as a cost-effective and sustainable platform capable of coping with these limitations based on the biocatalytic action of plants, bacteria, fungi and microalgae. Indeed, biological-based purification systems can improve the energy efficiency of buildings, while providing additional aesthetic and psychological benefits. This review critically assessed the state-of-the-art of the indoor air pollution problem and prevention strategies, along with the recent advances in physical-chemical and biological technologies for indoor pollutants abatement., Ministerio de Ciencia, Innovación y Universidades [proyecto RTI2018-0-096441-B-I00], Junta de Castilla y León (CLU 2017-09) y (UIC 071), EU-FEDER program, European Union [grant, CLU 2017-09]

Producción Científica, In this work, a dynamic optimizer (DO) is enhanced with elements taken from the Modifier Adaptation (MA) methodology for Real-Time Optimization (RTO). The objective is to use the capability of MA methodologies to reach the real optimum of a process despite the existence of process-model mismatch. The modifiers are computed during a process transient, without waiting for several steady states to occur, speeding up the time required to reach the plant optimum. The architecture proposed includes a modified dynamic optimization, a module for estimating the model states and an additional module for direct estimation of the modifiers during transient. The proposed approach was applied in a well-known benchmark example: the Williams-Otto reactor, where the model and process have significant parametric and structural mismatch. The results show that the proposed integration is capable of bringing the process closer to the real optimal economic operation point., Junta de Castilla y León y EU-FEDER (CLU 2017-09) y (UIC 233), Agencia Estatal de Investigación AEI (proyecto PGC2018-099312-B-C31)

Producción Científica, Europe’s capacity to explore the envisaged pathways that achieve its near- and long-term energy and climate objectives needs to be significantly enhanced. In this perspective, we discuss how this capacity is supported by energy and climate-economy models, and how international modelling teams are organised within structured communication channels and consortia as well as coordinate multi-model analyses to provide robust scientific evidence. Noting the lack of such a dedicated channel for the highly active yet currently fragmented European modelling landscape, we highlight the importance of transparency of modelling capabilities and processes, harmonisation of modelling parameters, disclosure of input and output datasets, interlinkages among models of different geographic granularity, and employment of models that transcend the highly harmonised core of tools used in model inter-comparisons. Finally, drawing from the COVID-19 pandemic, we discuss the need to expand the modelling comfort zone, by exploring extreme scenarios, disruptive innovations, and questions that transcend the energy and climate goals across the sustainability spectrum. A comprehensive and comprehensible multi-model framework offers a real example of “collective” science diplomacy, as an instrument to further support the ambitious goals of the EU Green Deal, in compliance with the EU claim to responsible research., H2020 European Commission Projects “PARIS REINFORCE” under Grant Agreement No. 820846, “LOCOMOTION” under Grant Agreement No. 821105, “SENTINEL” under Grant Agreement No. 837089, and “NAVIGATE” under Grant Agreement No. 821124.

Producción Científica, Deep learning models are not yet fully applied to fluid dynamics predictions, while they are the state-of-the-art solution in many other areas i.e. video and language processing, finance, robotics . Prediction problems on high-dimensional, complex dynamical systems require deep learning models devised to avoid overfitting while maintaining the required model complexity. In this work we present a deep learning prediction model based on a combination of 3D convolutional layers and a low-dimensional intermediate representation that is specifically designed to forecast the future states of this type of dynamical systems. The model predicts p future velocity-field time-slices (samples) based on k past samples from a training dataset consisting of a synthetic jet in transitional regime. The complexity of this flow is characterized by two topology patterns that are periodically changing, making this flow as a suitable example to test the performance of deep learning models to predict time states in complex flows. Moreover, the wide number of applications of synthetic jets (i.e.: fluid mixing, heat transfer enhancement, flow control), points out this example as a reference for future applications, where modeling synthetic jet flows with a reduced computational effort is needed. This work additionally opens up research opportunities for other areas that also operate with complex and high-dimensional time-series data: future frame video prediction, network traffic forecasting, network intrusion detection . The proposed model is presented in detail. A comprehensive analysis of the results is provided. The results are based on a strict validation strategy to ensure its generalization. The model offers an average symmetric mean absolute error (sMAPE) and a relative root mean square error (RRMSE) of 1.068 and 0.026 respectively (one order of magnitude improvement over low-rank approximation tools), using 10 past samples and predicting 6 future samples of a two-dimensional velocit, Ministerio de Ciencia, Innovación y Universidades Proyectos de I+D+i ‘‘Retos investigación’’, (grant RTI2018-098958- B-I00)

Producción Científica, Including high-dimensional categorical predictors in a machine learning model is a major challenge. This is particularly appropriate for the IP and Port addresses of network connections when they are considered as predictors (features) in machine learning models. These features are particularly important for network intrusion detection, as many attacks exploit information about IP/Port addresses. The sparsity and high dimensionality of these features make it difficult their inclusion into the models, being discarded as useful information in many cases. This work proposes to replace the original network addresses by new features based on a set of distances defined between different components of the source and destination IP and Port addresses. These distances incorporate information on the probability of co-occurrence of source and destination addresses. The distances are calculated using a dense, low-dimensional vector representation (embedding) of the different network address components. The embeddings are obtained with a neural network, which requires few computational resources, plus an additional hash function that collapses the extremely large range of IP and Port values, making the model implementation feasible. A self-supervised learning framework under a hierarchical model is used to train the encoding network. The novel features can be used to predict future co-occurrence of source and destination network addresses, and, when applied as features in a supervised model, they significantly increase the prediction performance of most classifiers for the detection of network intrusions. We demonstrate this prediction improvement over two modern network intrusion datasets: CICIDS2017 and CICDDoS2019., Ministerio de Ciencia, Innovación y Universidades Proyectos de I+D+i ‘‘Retos investigación’’, (grant RTI2018-098958- B-I00)

Producción Científica, Creating additional value out of biogas during waste treatment has become a priority in past years. Biogas bioconversion into valuable bioproducts such as biopolymers has emerged as a promising strategy. This work assessed the operational feasibility of a bubble column bioreactor (BCB) implemented with gas recirculation and inoculated with a polyhydroxybutyrate (PHB)-producing strain using biogas as substrate. The BCB was initially operated at empty bed residence times (EBRTs) ranging from 30 to 120 min and gas recirculation ratios (R) from 0 to 30 to assess the gas-to-liquid mass transfer and bioconversion of CH4. Subsequently, the BCB was continuously operated at a R of 30 and an EBRT of 60 min under excess of nitrogen and nitrogen feast-famine cycles of 24 h:24 h to trigger PHB synthesis. Gas recirculation played a major role in CH4 gas–liquid transfer, providing almost fourfold higher CH4 elimination capacities (~41 g CH4 m−3 h−1) at the highest R and EBRT of 60 min. The long-term operation under N excess conditions entailed nitrite accumulation (induced by O2 limiting conditions) and concurrent methanotrophic activity inhibition above ~60 mg N-NO2− L−1. Adjusting the N-NO3− supply to match microbial N demand successfully prevented nitrite accumulation. Finally, the N feast-famine 24 h:24 h strategy supported a stable CH4 conversion with a removal efficiency of 70% along with a continuous PHB production, which yielded PHB accumulations of 14.5 ± 2.9% (mg PHB mg−1 total suspended solids × 100). These outcomes represent the first step towards the integration of biogas biorefineries into conventional anaerobic digestion plants., Ministerio de Ciencia e Innovación (grant BES-2016-077160) y (proyecto CTM2015-70442-R), Junta de Castilla y León y EU-FEDER (CLU 2017-09) , (UIC 526071) y (VA281P18)

Producción Científica, In this study, an innovative approach is proposed for the integral valorization of all sugars (cellulosic and hemicellulosic) contained in a lignocellulosic residue, as is brewer's spent grain (BSG), through the production of an advanced biofuel such as biobutanol. For this purpose, the whole slurry obtained in the microwave assisted dilute sulfuric acid pretreatment under optimized conditions (147 °C, 2 min and 1.26% H2SO4) at a biomass loading as high as 15% (w/v) was enzymatically hydrolyzed without previous solid-liquid separation and the highly concentrated solution of sugars recovered was fermented to butanol by Clostridium beijerinckii after detoxification with activated charcoal. In this way, all sugars (pentoses and hexoses) contained in BSG could be fermented using a single bioreactor, leading to 11 g/L of butanol and 16 g/L of ABE, which correspond with butanol and ABE yields of 0.21 and 0.32 g/g, respectively. The mass balance revealed then an overall yield of 91 kg butanol/t BSG and 138 kg ABE/t BSG could be reached., Junta de Castilla y León y EU-FEDER (VA010P17, CLU 2017-09, UIC 129).

Producción Científica, Biogas produced at wastewater treatment plants and landfills contains trace levels of volatile methyl siloxanes (VMS) that are responsible for abrasion, corrosion and erosion of equipment during biogas storage and combustion. This research comparatively evaluated the removal of the most common VMS (L2, L3, D4, and D5) under aerobic conditions in a conventional biotrickling filter (BTF) and a two-phase partitioning BTF (TP-BTF) with silicone oil (at 30%) as organic phase. The TP-BTF showed a superior performance compared to the conventional BTF, increasing the total VMS removal from <30% in the BTF up to ∼70% in the TP-BTF. The highest REs in the TP-BTF were recorded for D4 and D5, reaching values of 80–90%, corresponding to ECs between 0.12 and 0.17 g m−3.h−1. Slightly lower values were obtained for L3 (70–80%), and the lowest performance was recorded for L2 (20–60%) due to the high vapor pressure of this siloxane and therefore its lower affinity by the organic phase. Surprisingly, despite the different inocula used, a similar microbial community was found by the end of operation of both BTFs, with KMBC-112, Reynarella and Chitinophaga as the dominant genera., Junta de Castilla y León y EU-FEDER (CLU 2017-09 and UIC 071), European Union’s Horizon 2020 research and innovation program. grant agreement no. 745785

Producción Científica, The validation of a control strategy for biogas upgrading via light-driven CO2 consumption by microalgae and H2S oxidation by oxidizing bacteria using the oxygen photosynthetically generated was performed in a semi-industrial scale (9.6 m3) photobioreactor. The control system was able to support CO2 concentrations lower than 2% with O2 contents ≤ 1% regardless of the pH in the cultivation broth (ranging from 9.05 to 9.50). Moreover, the control system was efficient to cope with variations in biogas flowrate from 143 to 420 L h−1, resulting in a biomethane composition of CO2 < 2.4%, CH4 > 95.5%, O2 < 1% and no H2S. Despite the poor robustness of this technology against failures in biogas and liquid supply (CH4 concentration of 67.5 and 70.9% after 2 h of biogas or liquid stoppage, respectively), the control system was capable of restoring biomethane quality in less than 2 h when biogas or liquid supply was resumed., Junta de Castilla y León y Programa Europeo FEDER (CLU 2017-09) y (UIC 071)., European Union’s Horizon 2020 research and innovation programme under grant agreement No. 689242

Producción Científica, The potential of a novel Fe/EDTA/carbonate-based scrubbing process for the simultaneous removal of H2S and CO2 from biogas was studied by evaluating the influence of Fe/EDTA molarity (M), carbonate concentration (IC), biogas (B), air (A) and liquid (L) flow rates on biogas upgrading performance using a Taguchi L16(45) experimental design. The ANOVA demonstrated that molarity of the Fe/EDTA solution was a significant factor influencing H2S concentration (0.035 % at 0.00 M to 0.000 % at 0.05 M). IC impacted on the concentrations of CO2 (13.1 and 4.5 % at 4000 and 10,000 mg L−1, respectively), N2 and CH4 (85.9 and 94.5 % at 4000 and 10,000 mgIC L−1, respectively). The biogas flow rate affected the concentrations of CO2 (2.5 to 13.8% at 10 and 40 mL min−1, respectively), O2, N2 and CH4 (95.9 to 85.4% at 10 and 40 mL min−1, respectively). Likewise, the recycling liquid flow rate affected CO2 (8.3 and 5.9 % at 5 and 30 mL min−1, respectively), O2, N2 and CH4 (90.5 and 93.3 % at 5 and 40 mL min−1, respectively) concentrations. Finally, the air flow rate impacted on CO2 (10.8 and 6.7 % at 800 and 1000 mL min−1, respectively), H2S, N2 and CH4 (87.9 and 92.2 % at 800 and 1000 mL min−1, respectively) concentrations. Process optimization provided the optimal conditions for each control factor. Continuous biogas upgrading operation at M2-IC1-B2-A4-L4 (0.05 M, 10,000 mgIC L−1, 10 mL min−1, 1000 mL min−1 and 30 mL min−1, respectively) provided CH4, CO2, O2, N2 and H2S concentration in the upgrading biogas of 97.4, 1.4, 0.29, 0.97 and 0%, respectively, which complied with biomethane regulations., Junta de Castilla y León y EU-FEDER (CLU 2017-09 and UIC 071)

Producción Científica, The development of biological Power-to-Methane in-situ technologies aimed at producing biomethane directly in a single anaerobic digestion unit by the supply of external hydrogen, find its limiting step in the gas-to-liquid mass transfer of poorly soluble hydrogen. Increasing the operating pressure with an exogenous hydrogen supply could enhance transfer rates of hydrogen and carbon dioxide (enriching gas phase with methane) and simultaneously control the liquid media pH because the methanation of hydrogen and carbon dioxide prevents the acidification caused by carbon dioxide/bicarbonate equilibrium displacement. Thus, the feasibility of operating the anaerobic digestion of sludge at a pressure higher than the atmospheric pressure with an exogenous hydrogen supply to improve the solubilisation of hydrogen and subsequent bioconversion of hydrogen and carbon dioxide into methane by methanogenic archaea was studied. A mesophilic sludge digester (35 L) was operated at variable absolute pressure up to 300 kPa. Hydrogen was continuously supplied through the sludge recirculation stream, coupled to a static mixer. Hydrogen conversion increased with the operating pressure (up to 99%), and the methane concentration in the digester off-gas averaged 92.9 ± 2.3% at 300 kPa (maximum of 95.2%). pH approached 7 under such conditions, and the efficiency of organic matter removal was similar to that observed during conventional anaerobic digestion at atmospheric pressure without a detrimental accumulation of volatile fatty acids. This study confirmed that increasing the system pressure (mass transfer driving force) can be a viable alternative to high energy-consuming mixing methods to enhance the hydrogen gas-liquid mass transfer., Junta de Castilla y León, programa EU-FEDER (CLU 2017-09 y UIC 071)

Producción Científica, This study proposes an integrated biorefinery of brewer's spent grain (BSG) based on the application of a microwave pretreatment to obtain bioproducts, such as arabinoxylans (AX) and an advanced biofuel, such as biobutanol. A prehydrolysate with 17 g/L AX was obtained at 172 °C and 0.38 M NaOH, which were subsequently precipitated using an organosolvent process, recovering 133 kg AX/t BSG. The subsequent enzymatic hydrolysis with endo-xylanases significantly increased the concentration ofoligomers with 2-6 units of xylose. The presence of oligosaccharides with a degree of polymerization (DP) from 3 to 27 was confirmed by MALDI-TOF MS. On the other hand, the pretreated solid residue obtained in the microwave assisted alkaline pretreatment was enzymatically hydrolyzed with cellulases and fermented by Clostridium beijerinckii, producing 9.9 g/L butanol (28 kg butanol/t BSG and 37 kg ABE/t BSG). Thus, the potential for the efficient use of BSG in an integrated biorefinery was demonstrated., Junta de Castilla y León y UE-FEDER (VA010P17, CLU 2017-09 y UIC 129)

Producción Científica, Nowadays, the extensive use of inorganic fertilizers has increased the salinity of soil and decreased optimal assimilation of nutrients by crops. Organic carbon is basic for controlling the nutrient level in soil and nutrient assimilation by plants. The objective of this study was to develop a process for recovering organic carbon using compost from mixed municipal waste as raw material. The use of fertilizers from organic residues could replace mineral fertilizers, contributing to resources preservation and recycling of organic matter. In this way, a Taguchi experimental design was proposed to select the most suitable operating conditions for recovering organic carbon from the organic residue. The variable factors were the solid:liquid ratio, type of solvent, extraction time, and particle size. The optimum extraction conditions were: solid:liquid ratio 1:2.5, 1 M potassium hydroxide (KOH), 72 h, and particle size > 1 mm. Subsequent experiments concluded that separating the mixed municipal waste compost (MMWC) by fractions of different particle sizes before extraction process is not recommended. Under these conditions, the total organic carbon concentration in the extract was 6.9% w/w, of which the content of humic acids was 47.6%. On the other hand, the extract complies with the legal requirements of Regulation (EU) 2019/1009 for fertilizing products regarding composition. Germination tests were carried out to analyze the phytotoxic effects of organic extracts. Finally, a preliminary economic study showed the viability for a production plant with a capacity of 300 kg/h of MMWC. The production of liquid fertilizer was 200 L per 100 kg of dry compost, and the estimated sale price to obtain economic benefits was 1 €/L of fertilizer for a plant whose total investment cost was 1,600 k€., INTERREG V-569A Spain-Portugal (POCTEP) 2014-2020 and EU-FEDER (project 0119_VALORCOMP_2_P), Junta de Castilla y León y EU-FEDER (UIC 572129) y (CLU2017-09), Junta de Castilla y León (E-47-2019-0114592)

Producción Científica, Four different types of biogas diffusers (metallic of 2 µm, porous stone, and two ceramic membranes of 0.2 and 0.4 µm) were evaluated to improve the quality of biomethane in an outdoor pilot scale photobioreactor interconnected to an external biogas absorption unit. Each type of diffuser was tested independently using three different liquid to biogas (L/G) ratios (0.5, 1 and 2). No significant difference was recorded in the CH4 concentrations of biomethane (i.e. > 93.0%) working with the different types of diffusers at L/G ratios > 1. Only the metallic biogas diffuser supported CH4 concentrations higher than 94.0% at a L/G ratio of 0.5. The increase in L/G ratio induced the stripping of the dissolved N2 and O2 into the biogas, which compensated the decrease in CO2 concentration mediated by the higher pH value of the scrubbing solution. The ANOVA of the results here obtained confirmed that both the type of biogas diffuser and the L/G ratio significantly determined the quality of the upgraded biogas., Junta de Castilla y León y EU-FEDER (CLU 2017-09 y UIC 071)

Producción Científica, Achieving ambitious reductions in greenhouse gases (GHG) is particularly challenging for transportation due to the technical limitations of replacing oil-based fuels. We apply the integrated assessment model MEDEAS-World to study four global transportation decarbonization strategies for 2050. The results show that a massive replacement of oil-fueled individual vehicles to electric ones alone cannot deliver GHG reductions consistent with climate stabilization and could result in the scarcity of some key minerals, such as lithium and magnesium. In addition, energy-economy feedbacks within an economic growth system create a rebound effect that counters the benefits of substitution. The only strategy that can achieve the objectives globally follows the Degrowth paradigm, combining a quick and radical shift to lighter electric vehicles and non-motorized modes with a drastic reduction in total transportation demand., European Union's Horizon 2020 research and innovation programme under grant agreement no 691287 and 821105, respectively., Ministerio de Economía, Industria y Competitividad (Project ECO2017-85110-R), Ministerio de Economía, Industria y Competitividad (Project FJCI-2016-28833)

Producción Científica, Today's decision-makers rely heavily on Integrated Assessment Models to guide the decarbonisation of the energy system. Uncertainty is embedded in the assumptions these models are built upon. Unless those uncertainties are adequately assessed, using Integrated Assessment Models for policy design is unadvised. In this work we run Monte Carlo simulations with the MEDEAS model at European Union scale to assess how the uncertainties on the main drivers of the transition affect key socioeconomic and environmental indicators. In addition, One-at-a-time sensitivity exploration is performed to grade the contribution of a set of model parameters to the uncertainty in the same key indicators. The combination of the uncertainties in the model drivers magnify the uncertainty in the model outputs, which widens over time. Parameters affecting sectorial and households' energy efficiency and households' transport energy use ranked amongst the most impacting ones on simulation results., European Union's Horizon 2020 research and innovation program, grant agreement No 691287 of the Framework Program for Research and Innovation actions, H2020 LCE-21-2015