Influencia del estilo parental en el autoconcepto del niño

Quinzenes Jornades de Foment de la Investigació de la FCHS (Any 2009-2010

EU Member States' Institutional Twitter Campaigns on COVID-19 Vaccination: Analyses of Germany, Spain, France and Italy

The development of an effective vaccine against the SARS-CoV-2 coronavirus became the hope for halting the spread of the disease. In recent years, social networks have become important tools for political and strategic communication in the dialogue with citizens. Therefore, the messages emitted through them were important to address vaccine hesitancy and achieve collective immunity. This paper analyses the use of Twitter by politicians and institutions in EU Member States during the first fifty days after the Commission's marketing authorisation of the first COVID-19 vaccine (21 December 2020 to 8 February 2021). To do so, a triple approach content analysis was carried out (quantitative, qualitative and discursive on feelings) applied to 1913 tweets published by the official profiles of the prime ministers, health ministers, governments and health ministries of Germany, Spain, France and Italy, the four most populous EU countries. The results point out that politicians and institutions gave preference to other issues on their political agenda over vaccine-related issues. Moreover, previous research hypotheses, such as those related to the underutilization of the Twitter tool as a two-way communication channel with citizens, are validated

Deconstructing Biopolitical and Performative Modes of Gender in Spanish Science Fiction

This thesis investigates the distinctly Spanish works of science fiction created by Pedro Almodóvar and Elia Barceló through biopolitical and feminist frameworks. Utilizing the theories of feminist philosopher Judith Butler and sociologist Jemima Repo, we uncover associations between the fictional and theoretical that have seldom been studied in conjunction. The paper aims to demonstrate Almodóvar and Barceló’s unique narratives free from the confines of an unwavering gender stratum while simultaneously revealing the deteriorative effects of gender as a control apparatus. Deeply influenced by the post-Franco Madrid Movida movement, these creators exemplify the feminist ideals emerging from that progressive time, rejecting more conservative cultural dynamics. Their work offers a startling prescience for modern Spain, with elements mirrored in Butler and Repo’s gender-focused studies. Gender identity is malleable and non-essential to the functions of reproduction and identity in every piece we examine. That idea is central to this thesis, which intends to demonstrate the potential of subversion through fantastical Spanish science fiction narratives

Efectividad de la educación dietética para modificar el perfil lipídico en la adolescencia

Las enfermedades cardiovasculares son una de las principales causas de mortalidad en nuestro medio y Canarias es la comunidad autónoma con mayores tasas de mortalidad por enfermedad isquémica del corazón. Se pretende valorar la efectividad de la educación dietética para mejorar los hábitos dietéticos de ingesta de grasas en adolescentes cuando se imparte durante un periodo de tiemp

Optimization of the Perturbation Amplitude for EIS Measurements Using a Total Harmonic Distortion Based Method

[EN] Ohm's generalized law defines the concept of impedance. This law, and thus the definition itself, are only valid if the system fulfills the linearity condition. However, electrochemical systems are typically highly nonlinear. Consequently, the linearity condition can only be achieved in these systems if a low perturbation amplitude is used for performing EIS measurements. Nevertheless, the use of low amplitude perturbations leads to low signal-to-noise ratios, which result in high measurement errors. The concept of optimum amplitude arises from this tradeoff: the perturbation has to have an amplitude big enough in order to minimize the measurement errors (i.e. maximize the SNR), but at the same time, the perturbation has to have an amplitude small enough to avoid the generation of significant nonlinear effects that would distort the measured EIS spectra. In a previous work, a linearity assessment quantitative method based on the total harmonic distortion parameter was developed. In this work, the aforementioned THD method was applied for the perturbation amplitude selection for EIS measurements in a highly nonlinear model system: the cathodic electrode of an alkaline water electrolyzer. The THD method successfully obtained the optimum amplitudes both, for a constant amplitude strategy and for a frequency dependent strategy. The THD method also allowed to obtain the noise structure and to quantify the nonlinear effects. This method is slightly superior to the U-P method, a method based on the harmonic analysis of the output signal that was developed in earlier works. (C) 2018 The Electrochemical Society.The authors are very grateful to the Generalitat Valenciana for its economic support in form of Vali+d grant (Ref: ACIF-2013-268).Giner-Sanz, JJ.; Ortega Navarro, EM.; Pérez-Herranz, V. (2018). Optimization of the Perturbation Amplitude for EIS Measurements Using a Total Harmonic Distortion Based Method. Journal of The Electrochemical Society. 165(10):E488-E497. https://doi.org/10.1149/2.1021810jesSE488E49716510Sacco, A. (2017). Electrochemical impedance spectroscopy: Fundamentals and application in dye-sensitized solar cells. Renewable and Sustainable Energy Reviews, 79, 814-829. doi:10.1016/j.rser.2017.05.159Macdonald, J. R. (1992). Impedance spectroscopy. Annals of Biomedical Engineering, 20(3), 289-305. doi:10.1007/bf02368532Yuksel, R., Uysal, N., Aydinli, A., & Unalan, H. E. (2018). Paper Based, Expanded Graphite/Polypyrrole Nanocomposite Supercapacitors Free from Binders and Current Collectors. Journal of The Electrochemical Society, 165(2), A283-A290. doi:10.1149/2.1051802jesWang, C., Xiong, Y., Wang, H., Yang, N., Jin, C., & Sun, Q. (2018). «Pickles Method» Inspired Tomato Derived Hierarchical Porous Carbon for High-Performance and Safer Capacitive Output. Journal of The Electrochemical Society, 165(5), A1054-A1063. doi:10.1149/2.1001805jesZhou, X., Cao, L., Li, Z., Zhang, M., Kang, W., & Cheng, B. (2018). Rapid Synthesis of 3D Porous Nitrogen-Doped Carbon Nanospheres (N-CNSs) and Carbon Nanoboxes (CNBs) for Supercapacitor Electrodes. Journal of The Electrochemical Society, 165(5), A918-A923. doi:10.1149/2.0761805jesRanjith, P. M., Rao, M. T., Sapra, S., Suni, I. I., & Srinivasan, R. (2018). On the Anodic Dissolution of Tantalum and Niobium in Hydrofluoric Acid. Journal of The Electrochemical Society, 165(5), C258-C269. doi:10.1149/2.0691805jesJi, G., Macía, L. F., Allaert, B., Hubin, A., & Terryn, H. (2018). Odd Random Phase Electrochemical Impedance Spectroscopy to Study the Corrosion Behavior of Hot Dip Zn and Zn-Alloy Coated Steel Wires in Sodium Chloride Solution. Journal of The Electrochemical Society, 165(5), C246-C257. doi:10.1149/2.0741805jesHorvath, D., & Simpson, M. F. (2018). Electrochemical Monitoring of Ni Corrosion Induced by Water in Eutectic LiCl-KCl. Journal of The Electrochemical Society, 165(5), C226-C233. doi:10.1149/2.0391805jesBertocci, U. (1997). Noise Resistance Applied to Corrosion Measurements. Journal of The Electrochemical Society, 144(1), 31. doi:10.1149/1.1837361Bertocci, U. (1997). Noise Resistance Applied to Corrosion Measurements. Journal of The Electrochemical Society, 144(1), 37. doi:10.1149/1.1837362Bertocci, U. (1997). Noise Resistance Applied to Corrosion Measurements. Journal of The Electrochemical Society, 144(8), 2786. doi:10.1149/1.1837896Vijayakumar, E., Kang, S.-H., & Ahn, K.-S. (2018). Facile Electrochemical Synthesis of Manganese Cobalt Sulfide Counter Electrode for Quantum Dot-Sensitized Solar Cells. Journal of The Electrochemical Society, 165(5), F375-F380. doi:10.1149/2.1211805jesKharel, P. L., Zamborini, F. P., & Alphenaar, B. W. (2018). Enhancing the Photovoltaic Performance of Dye-Sensitized Solar Cells with Rare-Earth Metal Oxide Nanoparticles. Journal of The Electrochemical Society, 165(3), H52-H56. doi:10.1149/2.1311802jesGong, C., Hong, X., Xiang, S., Wu, Z., Sun, L., Ye, M., & Lin, C. (2018). NiS2Nanosheet Films Supported on Ti Foils: Effective Counter Electrodes for Quantum Dot-Sensitized Solar Cells. Journal of The Electrochemical Society, 165(3), H45-H51. doi:10.1149/2.0171803jesMitra, D., Trinh, P., Malkhandi, S., Mecklenburg, M., Heald, S. M., Balasubramanian, M., & Narayanan, S. R. (2018). An Efficient and Robust Surface-Modified Iron Electrode for Oxygen Evolution in Alkaline Water Electrolysis. Journal of The Electrochemical Society, 165(5), F392-F400. doi:10.1149/2.1371805jesYoon, S., Kim, J., Lim, J.-H., & Yoo, B. (2018). Cobalt Iron-Phosphorus Synthesized by Electrodeposition as Highly Active and Stable Bifunctional Catalyst for Full Water Splitting. Journal of The Electrochemical Society, 165(5), H271-H276. doi:10.1149/2.1221805jesFrey, C. E., Fang, Q., Sebold, D., Blum, L., & Menzler, N. H. (2018). A Detailed Post Mortem Analysis of Solid Oxide Electrolyzer Cells after Long-Term Stack Operation. Journal of The Electrochemical Society, 165(5), F357-F364. doi:10.1149/2.0961805jesGiner-Sanz, J. J., Ortega, E. M., & Pérez-Herranz, V. (2017). Experimental Quantification of the Effect of Nonlinearities on the EIS Spectra of the Cathodic Electrode of an Alkaline Electrolyzer. Fuel Cells, 17(3), 391-401. doi:10.1002/fuce.201600137Atar, N., & Yola, M. L. (2018). Core-Shell Nanoparticles/Two-Dimensional (2D) Hexagonal Boron Nitride Nanosheets with Molecularly Imprinted Polymer for Electrochemical Sensing of Cypermethrin. Journal of The Electrochemical Society, 165(5), H255-H262. doi:10.1149/2.1311805jesWippermann, K., Giffin, J., & Korte, C. (2018). In Situ Determination of the Water Content of Ionic Liquids. Journal of The Electrochemical Society, 165(5), H263-H270. doi:10.1149/2.0991805jesZhou, W.-H., Wang, H.-H., Li, W.-T., Guo, X.-C., Kou, D.-X., Zhou, Z.-J., … Wu, S.-X. (2018). Gold Nanoparticles Sensitized ZnO Nanorods Arrays for Dopamine Electrochemical Sensing. Journal of The Electrochemical Society, 165(12), G3001-G3007. doi:10.1149/2.0011811jesNakpetpoon, W., Vongsetskul, T., Limthongkul, P., & Tammawat, P. (2018). Disodium Terephthalate Ultrafine Fibers as High Performance Anode Material for Sodium-Ion Batteries under High Current Density Conditions. Journal of The Electrochemical Society, 165(5), A1140-A1146. doi:10.1149/2.0821805jesLandesfeind, J., Eldiven, A., & Gasteiger, H. A. (2018). Influence of the Binder on Lithium Ion Battery Electrode Tortuosity and Performance. Journal of The Electrochemical Society, 165(5), A1122-A1128. doi:10.1149/2.0971805jesCheng, Q., & Zhang, Y. (2018). Multi-Channel Graphite for High-Rate Lithium Ion Battery. Journal of The Electrochemical Society, 165(5), A1104-A1109. doi:10.1149/2.1171805jesXia, S., Li, F., Cheng, F., Li, X., Sun, C., Liu, J.-J., & Hong, G. (2018). Synthesis of Spherical Fluorine Modified Gradient Li-Ion Battery Cathode Material LiNi0.80Co0.15Al0.05O2by Simple Solid Phase Method. Journal of The Electrochemical Society, 165(5), A1019-A1026. doi:10.1149/2.1021805jesGarsany, Y., Atkinson, R. W., Sassin, M. B., Hjelm, R. M. E., Gould, B. D., & Swider-Lyons, K. E. (2018). Improving PEMFC Performance Using Short-Side-Chain Low-Equivalent-Weight PFSA Ionomer in the Cathode Catalyst Layer. Journal of The Electrochemical Society, 165(5), F381-F391. doi:10.1149/2.1361805jesGiner-Sanz, J. J., Ortega, E. M., & Pérez-Herranz, V. (2018). Mechanistic equivalent circuit modelling of a commercial polymer electrolyte membrane fuel cell. Journal of Power Sources, 379, 328-337. doi:10.1016/j.jpowsour.2018.01.066Giner-Sanz, J. J., Ortega, E. M., & Pérez-Herranz, V. (2018). Statistical analysis of the effect of temperature and inlet humidities on the parameters of a semiempirical model of the internal resistance of a polymer electrolyte membrane fuel cell. Journal of Power Sources, 381, 84-93. doi:10.1016/j.jpowsour.2018.01.093Liu, H., George, M. G., Ge, N., Muirhead, D., Shrestha, P., Lee, J., … Bazylak, A. (2018). Microporous Layer Degradation in Polymer Electrolyte Membrane Fuel Cells. Journal of The Electrochemical Society, 165(6), F3271-F3280. doi:10.1149/2.0291806jesOrazem M. E. Tribollet B. , Electrochemical Impedance Spectroscopy, John Wiley & Sons, Hoboken (2008).Lasia A. , Electrochemical Impedance Spectroscopy and its applications, Springer, London (2014).Barsoukov E. Macdonald J. R. , Impedance Spectroscopy. Theory, experiment and applications, John Wiley & Sons, New Jersey (2005).Choi, J.-H., Park, J.-S., & Moon, S.-H. (2002). Direct Measurement of Concentration Distribution within the Boundary Layer of an Ion-Exchange Membrane. Journal of Colloid and Interface Science, 251(2), 311-317. doi:10.1006/jcis.2002.8407Macdonald, D. D., Sikora, E., & Engelhardt, G. (1998). Characterizing electrochemical systems in the frequency domain. Electrochimica Acta, 43(1-2), 87-107. doi:10.1016/s0013-4686(97)00238-7Giner-Sanz, J. J., Ortega, E. M., & Pérez-Herranz, V. (2014). Hydrogen crossover and internal short-circuit currents experimental characterization and modelling in a proton exchange membrane fuel cell. International Journal of Hydrogen Energy, 39(25), 13206-13216. doi:10.1016/j.ijhydene.2014.06.157Giner-Sanz, J. J., Ortega, E. M., & Pérez-Herranz, V. (2015). Statistical Analysis of the Effect of the Temperature and Inlet Humidities on the Parameters of a PEMFC Model. Fuel Cells, 15(3), 479-493. doi:10.1002/fuce.201400163Hirschorn, B., Tribollet, B., & Orazem, M. E. (2008). On Selection of the Perturbation Amplitude Required to Avoid Nonlinear Effects in Impedance Measurements. Israel Journal of Chemistry, 48(3-4), 133-142. doi:10.1560/ijc.48.3-4.133Victoria, S. N., & Ramanathan, S. (2011). Effect of potential drifts and ac amplitude on the electrochemical impedance spectra. Electrochimica Acta, 56(5), 2606-2615. doi:10.1016/j.electacta.2010.12.007Giner-Sanz, J. J., Ortega, E. M., & Pérez-Herranz, V. (2016). Harmonic analysis based method for linearity assessment and noise quantification in electrochemical impedance spectroscopy measurements: Theoretical formulation and experimental validation for Tafelian systems. Electrochimica Acta, 211, 1076-1091. doi:10.1016/j.electacta.2016.06.133Giner-Sanz, J. J., Ortega, E. M., & Pérez-Herranz, V. (2017). Harmonic Analysis Based Method for Perturbation Amplitude Optimization for EIS Measurements. Journal of The Electrochemical Society, 164(13), H918-H924. doi:10.1149/2.1451713jesGiner-Sanz, J. J., Ortega, E. M., & Pérez-Herranz, V. (2016). Optimization of the Perturbation Amplitude for Impedance Measurements in a Commercial PEM Fuel Cell Using Total Harmonic Distortion. Fuel Cells, 16(4), 469-479. doi:10.1002/fuce.201500141Gode, P., Jaouen, F., Lindbergh, G., Lundblad, A., & Sundholm, G. (2003). Influence of the composition on the structure and electrochemical characteristics of the PEFC cathode. Electrochimica Acta, 48(28), 4175-4187. doi:10.1016/s0013-4686(03)00603-0Yuan, X., Sun, J. C., Wang, H., & Zhang, J. (2006). AC impedance diagnosis of a 500W PEM fuel cell stack. Journal of Power Sources, 161(2), 929-937. doi:10.1016/j.jpowsour.2006.07.020Fernández Pulido, Y., Blanco, C., Anseán, D., García, V. M., Ferrero, F., & Valledor, M. (2017). Determination of suitable parameters for battery analysis by Electrochemical Impedance Spectroscopy. Measurement, 106, 1-11. doi:10.1016/j.measurement.2017.04.022Fasmin, F., & Srinivasan, R. (2015). Detection of nonlinearities in electrochemical impedance spectra by Kramers–Kronig Transforms. Journal of Solid State Electrochemistry, 19(6), 1833-1847. doi:10.1007/s10008-015-2824-9Giner-Sanz, J. J., Ortega, E. M., & Pérez-Herranz, V. (2015). Montecarlo based quantitative Kramers–Kronig test for PEMFC impedance spectrum validation. International Journal of Hydrogen Energy, 40(34), 11279-11293. doi:10.1016/j.ijhydene.2015.03.135Agarwal, P. (1995). Application of Measurement Models to Impedance Spectroscopy. Journal of The Electrochemical Society, 142(12), 4159. doi:10.1149/1.2048479Boukamp, B. A. (1995). A Linear Kronig-Kramers Transform Test for Immittance Data Validation. Journal of The Electrochemical Society, 142(6), 1885. doi:10.1149/1.2044210BOUKAMP, B., & ROSSMACDONALD, J. (1994). Alternatives to Kronig-Kramers transformation and testing, and estimation of distributions. Solid State Ionics, 74(1-2), 85-101. doi:10.1016/0167-2738(94)90440-5Orazem, M. E., & Tribollet, B. (2008). An integrated approach to electrochemical impedance spectroscopy. Electrochimica Acta, 53(25), 7360-7366. doi:10.1016/j.electacta.2007.10.075Shukla, P. K., Orazem, M. E., & Crisalle, O. D. (2004). Validation of the measurement model concept for error structure identification. Electrochimica Acta, 49(17-18), 2881-2889. doi:10.1016/j.electacta.2004.01.047Orazem, M. E. (2004). A systematic approach toward error structure identification for impedance spectroscopy. Journal of Electroanalytical Chemistry, 572(2), 317-327. doi:10.1016/j.jelechem.2003.11.059Orazem, M. E., Shukla, P., & Membrino, M. A. (2002). Extension of the measurement model approach for deconvolution of underlying distributions for impedance measurements. Electrochimica Acta, 47(13-14), 2027-2034. doi:10.1016/s0013-4686(02)00065-8Agarwal, P., Orazem, M. E., & Garcia-Rubio, L. H. (1996). The influence of error structure on interpretation of impedance spectra. 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Optimization of the electrochemical impedance spectrosc

Harmonic analysis based method for linearity assessment and noise quantification in electrochemical impedance spectroscopy measurements: Theoretical formulation and experimental validation for Tafelian systems

Electrochemical Impedance Spectroscopy (EIS) is an electrochemical measurement technique that has been applied to a broad range of applications. Three conditions must be fulfilled in order to obtain valid EIS measurements: causality, linearity and stationarity. The non fulfilment of any of these conditions may lead to distorted and biased EIS spectra. Consequently, the verification of the four fundamental conditions is mandatory before accepting any results extracted from an EIS spectrum. In this work, a harmonic analysis based method for linearity assessment and noise quantification in EIS measurements is presented, and validated both from an experimental point of view and from a theoretical point of view, for Tafelian systems. It was shown that the presented method was able to quantitatively assess the nonlinearity of the system; and to quantify and characterize the noise. Moreover, the presented method is able to determine the threshold frequency of the system above which the system does not present significant nonlinear effects even for very large perturbation amplitudes.The authors are very grateful to the Generalitat Valenciana for its economic support in form of Vali+d grant (Ref: ACIF-2013-268).Giner-Sanz, JJ.; Ortega Navarro, EM.; Pérez-Herranz, V. (2016). Harmonic analysis based method for linearity assessment and noise quantification in electrochemical impedance spectroscopy measurements: Theoretical formulation and experimental validation for Tafelian systems. Electrochimica Acta. 211:1076-1091. doi:10.1016/j.electacta.2016.06.133S1076109121

Statistical analysis of the effect of temperature and inlet humidities on the parameters of a semiempirical model of the internal resistance of a polymer electrolyte membrane fuel cell

[EN] he internal resistance of a PEM fuel cell depends on the operation conditions and on the current delivered by the cell. This work's goal is to obtain a semiempirical model able to reproduce the effect of the operation current on the internal resistance of an individual cell of a commercial PEM fuel cell stack; and to perform a statistical analysis in order to study the effect of the operation temperature and the inlet humidities on the parameters of the model. First, the internal resistance of the individual fuel cell operating in different operation conditions was experimentally measured for different DC currents, using the high frequency intercept of the impedance spectra. Then, a semiempirical model based on Springer and co-workers¿ model was proposed. This model is able to successfully reproduce the experimental trends. Subsequently, the curves of resistance versus DC current obtained for different operation conditions were fitted to the semiempirical model, and an analysis of variance (ANOVA) was performed in order to determine which factors have a statistically significant effect on each model parameter. Finally, a response surface method was applied in order to obtain a regression model.The authors are very grateful to the Generalitat Valenciana for its economic support in form of Valid grant (Ref:. ACIF-2013-268)Giner-Sanz, JJ.; Ortega Navarro, EM.; Pérez-Herranz, V. (2018). Statistical analysis of the effect of temperature and inlet humidities on the parameters of a semiempirical model of the internal resistance of a polymer electrolyte membrane fuel cell. Journal of Power Sources. 381:84-93. https://doi.org/10.1016/j.jpowsour.2018.01.093S849338

Mechanistic equivalent circuit modelling of a commercial polymer electrolyte membrane fuel cell

[EN] Electrochemical impedance spectroscopy (EIS) has been widely used in the fuel cell field since it allows deconvolving the different physic-chemical processes that affect the fuel cell performance. Typically, EIS spectra are modelled using electric equivalent circuits. In this work, EIS spectra of an individual cell of a commercial PEM fuel cell stack were obtained experimentally. The goal was to obtain a mechanistic electric equivalent circuit in order to model the experimental EIS spectra. A mechanistic electric equivalent circuit is a semiempirical modelling technique which is based on obtaining an equivalent circuit that does not only correctly fit the experimental spectra, but which elements have a mechanistic physical meaning. In order to obtain the aforementioned electric equivalent circuit, 12 different models with defined physical meanings were proposed. These equivalent circuits were fitted to the obtained EIS spectra. A 2 step selection process was performed. In the first step, a group of 4 circuits were preselected out of the initial list of 12, based on general fitting indicators as the determination coefficient and the fitted parameter uncertainty. In the second step, one of the 4 preselected circuits was selected on account of the consistency of the fitted parameter values with the physical meaning of each parameter.The authors are very grateful to the Generalitat Valenciana for its economic support in form of Vali + d grant (Ref: ACIF-2013-268).Giner-Sanz, JJ.; Ortega Navarro, EM.; Pérez-Herranz, V. (2018). Mechanistic equivalent circuit modelling of a commercial polymer electrolyte membrane fuel cell. Journal of Power Sources. 379:328-337. https://doi.org/10.1016/j.jpowsour.2018.01.066S32833737