Nonreactive solute transport in soil columns: classical and fractional-calculus modeling

Vertical nonreactive solute transport data collected in three laboratory soil columns (made out of sediment samples from the Pampean aquifer located southeast of the Buenos Aires province) are contrasted with the explicit solutions of two model 1D linear PDEs: the classical advection–dispersion equation (ADE), and a fractional advection–dispersion equation (FADE) which has proven to be a useful modeling tool for highly inhomogeneous media exhibiting nontrivial scaling laws. Whereas two of the samples turn out to be quite homogeneous (thus requiring a fractional-derivative order γ → 2), the third one is best described by a FADE with fractional-derivative order γ = 1.68. This example illustrates the FADE’s ability to reveal self-similar geometric structures inside the sample.Fil: Benavente, Micaela Andrea. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Departamento de Matemática; ArgentinaFil: Deza, Roberto Raul. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Departamento de Física; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Físicas de Mar del Plata. Universidad Nacional de Mar del Plata. Facultad de Cs.exactas y Naturales. Instituto de Investigaciones Físicas de Mar del Plata; ArgentinaFil: Grondona, Sebastian. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Geología de Costas y del Cuaternario. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto de Geología de Costas y del Cuaternario; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Mascioli, S.. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Geología de Costas y del Cuaternario. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto de Geología de Costas y del Cuaternario; ArgentinaFil: Martinez, Daniel Emilio. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Geología de Costas y del Cuaternario. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto de Geología de Costas y del Cuaternario; Argentin

Upgrading of moist agro-industrial wastes by hydrothermal carbonization

This work focuses in the application of the hydrothermal carbonization (HTC) technology as a possible moist agro-industrial waste management treatment. Through this technique, olive mill, canned artichoke and orange wastes (OMW, CAW and OJW, respectively) were carbonized in a lab-scale high pressure reactor at different temperatures (200–250 °C) and durations (2, 4, 8 and 24 h) in order to obtain useful bioenergy feedstocks. The effect of the residence time and temperature on the properties of the bio-char obtained was studied through different characterization techniques. Material and energy balances were also performed to determine the potential energy saving of hydrothermal carbonization versus dry thermal treatments like torrefaction (TF). It is found that the moisture content of HTC-hydro-chars decreases as the temperature and duration increase, which implies that wet biomass can be upgraded and, at the same time, dewatered through HTC. The best results are found for the OMW, whose moisture content decreases from over 70% to less than 30% for the experiments carried out under the more severe conditions. Consequently, it is be possible to reach energy savings over 50% by using HTC instead of TF technologies. Regarding the hydro-char properties, the hydrothermal carbonization of the three organic wastes treated leaded to hydro-chars that present carbon contents and heating values closed to those of brown coal and great energy densifications, depending on the type of waste. Accordingly, it can be concluded that it is feasible to manage moist agro-industrial wastes via HTC, which is ostensibly more efficient than TF in terms of energy consumption.Authors kindly wish to thank the Spanish Ministry of Economy and Competitiveness (INNPACTO Project IPT-2012-0565-310000) and the Spanish Ministry for Education and Science (contract grant number 8850828) for financial support. The author V. Benavente also thanks the Conselleria d’Educación, Cultura i Esport, for a Ph.D. grant (contract grant number ACIF/2014/275)

Modelling Type 1 and 2 Wind Turbines based on IEC 61400-27-1: Transient Response under Voltage Dips

[EN] Wind power plants depend greatly on weather conditions, thus being considered intermittent, uncertain and non-dispatchable. Due to the massive integration of this energy resource in the recent decades, it is important that transmission and distribution system operators are able to model their electrical behaviour in terms of steady-state power flow, transient dynamic stability, and short-circuit currents. Consequently, in 2015, the International Electrotechnical Commission published Standard IEC 61400-27-1, which includes generic models for wind power generation in order to estimate the electrical characteristics of wind turbines at the connection point. This paper presents, describes and details the models for wind turbine topologies Types 1 and 2 following IEC 61400-27-1 for electrical simulation purposes, including the values for the parameters for the different subsystems. A hardware-in-the-loop combined with a real-time simulator is also used to analyse the response of such wind turbine topologies under voltage dips. The evolution of active and reactive powers is discussed, together with the wind turbine rotor and generator rotational speeds.This work was partially supported by the Spanish Ministry of Economy and Competitiveness and the European Union -FEDER Funds, ENE2016-78214-C2-1-R-; and the Spanish Ministry of Education, Culture and Sports -ref. FPU16/04282-.García-Sánchez, TM.; Muñoz-Benavente, I.; Gómez-Lázaro, E.; Fernández-Guillamón, A. (2020). Modelling Type 1 and 2 Wind Turbines based on IEC 61400-27-1: Transient Response under Voltage Dips. Energies. 13(16):1-19. https://doi.org/10.3390/en13164078S1191316Fernández-Guillamón, A., Villena-Lapaz, J., Vigueras-Rodríguez, A., García-Sánchez, T., & Molina-García, Á. (2018). An Adaptive Frequency Strategy for Variable Speed Wind Turbines: Application to High Wind Integration Into Power Systems. Energies, 11(6), 1436. doi:10.3390/en11061436Fernández-Guillamón, A., Das, K., Cutululis, N. A., & Molina-García, Á. (2019). Offshore Wind Power Integration into Future Power Systems: Overview and Trends. Journal of Marine Science and Engineering, 7(11), 399. doi:10.3390/jmse7110399Fernández-Guillamón, A., Gómez-Lázaro, E., Muljadi, E., & Molina-García, Á. (2019). Power systems with high renewable energy sources: A review of inertia and frequency control strategies over time. Renewable and Sustainable Energy Reviews, 115, 109369. doi:10.1016/j.rser.2019.109369Cardozo, C., van Ackooij, W., & Capely, L. (2018). Cutting plane approaches for frequency constrained economic dispatch problems. Electric Power Systems Research, 156, 54-63. doi:10.1016/j.epsr.2017.11.001Fernández-Guillamón, A., Martínez-Lucas, G., Molina-García, Á., & Sarasua, J. I. (2020). An Adaptive Control Scheme for Variable Speed Wind Turbines Providing Frequency Regulation in Isolated Power Systems with Thermal Generation. Energies, 13(13), 3369. doi:10.3390/en13133369Global Wind Report 2019https://gwec.net/global-wind-report-2019/Muñoz-Benavente, I., Hansen, A. D., Gómez-Lázaro, E., García-Sánchez, T., Fernández-Guillamón, A., & Molina-García, Á. (2019). Impact of Combined Demand-Response and Wind Power Plant Participation in Frequency Control for Multi-Area Power Systems. Energies, 12(9), 1687. doi:10.3390/en12091687Villena-Ruiz, R., Lorenzo-Bonache, A., Honrubia-Escribano, A., Jiménez-Buendía, F., & Gómez-Lázaro, E. (2019). Implementation of IEC 61400-27-1 Type 3 Model: Performance Analysis under Different Modeling Approaches. Energies, 12(14), 2690. doi:10.3390/en12142690Kumar, D., & Chatterjee, K. (2016). A review of conventional and advanced MPPT algorithms for wind energy systems. Renewable and Sustainable Energy Reviews, 55, 957-970. doi:10.1016/j.rser.2015.11.013Hansen, A. D., Iov, F., Blaabjerg, F., & Hansen, L. H. (2004). Review of Contemporary Wind Turbine Concepts and Their Market Penetration. Wind Engineering, 28(3), 247-263. doi:10.1260/0309524041590099Liang, X. (2017). Emerging Power Quality Challenges Due to Integration of Renewable Energy Sources. IEEE Transactions on Industry Applications, 53(2), 855-866. doi:10.1109/tia.2016.2626253Calif, R., & Schmitt, F. G. (2014). Multiscaling and joint multiscaling description of the atmospheric wind speed and the aggregate power output from a wind farm. Nonlinear Processes in Geophysics, 21(2), 379-392. doi:10.5194/npg-21-379-2014Calif, R., Schmitt, F. G., & Huang, Y. (2013). Multifractal description of wind power fluctuations using arbitrary order Hilbert spectral analysis. Physica A: Statistical Mechanics and its Applications, 392(18), 4106-4120. doi:10.1016/j.physa.2013.04.038Fernández‐Guillamón, A., Vigueras‐Rodríguez, A., & Molina‐García, Á. (2019). Analysis of power system inertia estimation in high wind power plant integration scenarios. IET Renewable Power Generation, 13(15), 2807-2816. doi:10.1049/iet-rpg.2019.0220Heredia, F.-J., Cuadrado, M. D., & Corchero, C. (2018). On optimal participation in the electricity markets of wind power plants with battery energy storage systems. Computers & Operations Research, 96, 316-329. doi:10.1016/j.cor.2018.03.004Zhang, W., & Fang, K. (2017). Controlling active power of wind farms to participate in load frequency control of power systems. IET Generation, Transmission & Distribution, 11(9), 2194-2203. doi:10.1049/iet-gtd.2016.1471Honrubia-Escribano, A., Gómez-Lázaro, E., Fortmann, J., Sørensen, P., & Martin-Martinez, S. (2018). Generic dynamic wind turbine models for power system stability analysis: A comprehensive review. Renewable and Sustainable Energy Reviews, 81, 1939-1952. doi:10.1016/j.rser.2017.06.005Moschitta, A., Carbone, P., & Muscas, C. (2011). Generalized Likelihood Ratio Test for Voltage Dip Detection. IEEE Transactions on Instrumentation and Measurement, 60(5), 1644-1653. doi:10.1109/tim.2011.2113110Moschitta, A., Carbone, P., & Muscas, C. (2012). Performance Comparison of Advanced Techniques for Voltage Dip Detection. IEEE Transactions on Instrumentation and Measurement, 61(5), 1494-1502. doi:10.1109/tim.2012.2183436Gallo, D., Landi, C., Luiso, M., & Fiorucci, E. (2014). Survey on Voltage Dip Measurements in Standard Framework. IEEE Transactions on Instrumentation and Measurement, 63(2), 374-387. doi:10.1109/tim.2013.2278996Ipinnimo, O., Chowdhury, S., Chowdhury, S. P., & Mitra, J. (2013). A review of voltage dip mitigation techniques with distributed generation in electricity networks. Electric Power Systems Research, 103, 28-36. doi:10.1016/j.epsr.2013.05.004Hossain, M. J., Pota, H. R., Ugrinovskii, V. A., & Ramos, R. A. (2010). Simultaneous STATCOM and Pitch Angle Control for Improved LVRT Capability of Fixed-Speed Wind Turbines. IEEE Transactions on Sustainable Energy, 1(3), 142-151. doi:10.1109/tste.2010.2054118Hossain, M. J., Pota, H. R., & Ramos, R. A. (2011). Robust STATCOM control for the stabilisation of fixed-speed wind turbines during low voltages. Renewable Energy, 36(11), 2897-2905. doi:10.1016/j.renene.2011.04.010Hossain, M. J., Pota, H. R., & Ramos, R. A. (2012). Improved low-voltage-ride-through capability of fixed-speed wind turbines using decentralised control of STATCOM with energy storage system. IET Generation, Transmission & Distribution, 6(8), 719. doi:10.1049/iet-gtd.2011.0537Wessels, C., Hoffmann, N., Molinas, M., & Fuchs, F. W. (2013). StatCom control at wind farms with fixed-speed induction generators under asymmetrical grid faults. IEEE Transactions on Industrial Electronics, 60(7), 2864-2873. doi:10.1109/tie.2012.2233694Obando-Montaño, A., Carrillo, C., Cidrás, J., & Díaz-Dorado, E. (2014). A STATCOM with Supercapacitors for Low-Voltage Ride-Through in Fixed-Speed Wind Turbines. Energies, 7(9), 5922-5952. doi:10.3390/en7095922Moghadasi, A., Sarwat, A., & Guerrero, J. M. (2016). A comprehensive review of low-voltage-ride-through methods for fixed-speed wind power generators. Renewable and Sustainable Energy Reviews, 55, 823-839. doi:10.1016/j.rser.2015.11.020Heydari-doostabad, H., Khalghani, M. R., & Khooban, M. H. (2016). A novel control system design to improve LVRT capability of fixed speed wind turbines using STATCOM in presence of voltage fault. International Journal of Electrical Power & Energy Systems, 77, 280-286. doi:10.1016/j.ijepes.2015.11.011Fortmann, J., Engelhardt, S., Kretschmann, J., Feltes, C., & Erlich, I. (2014). New Generic Model of DFG-Based Wind Turbines for RMS-Type Simulation. IEEE Transactions on Energy Conversion, 29(1), 110-118. doi:10.1109/tec.2013.2287251Goksu, O., Altin, M., Fortmann, J., & Sorensen, P. E. (2016). Field Validation of IEC 61400-27-1 Wind Generation Type 3 Model With Plant Power Factor Controller. IEEE Transactions on Energy Conversion, 31(3), 1170-1178. doi:10.1109/tec.2016.2540006Honrubia-Escribano, A., Jiménez-Buendía, F., Gómez-Lázaro, E., & Fortmann, J. (2016). Validation of Generic Models for Variable Speed Operation Wind Turbines Following the Recent Guidelines Issued by IEC 61400-27. Energies, 9(12), 1048. doi:10.3390/en9121048Honrubia-Escribano, A., Jimenez-Buendia, F., Gomez-Lazaro, E., & Fortmann, J. (2018). Field Validation of a Standard Type 3 Wind Turbine Model for Power System Stability, According to the Requirements Imposed by IEC 61400-27-1. IEEE Transactions on Energy Conversion, 33(1), 137-145. doi:10.1109/tec.2017.2737703Lorenzo-Bonache, A., Honrubia-Escribano, A., Jiménez-Buendía, F., Molina-García, Á., & Gómez-Lázaro, E. (2017). Generic Type 3 Wind Turbine Model Based on IEC 61400-27-1: Parameter Analysis and Transient Response under Voltage Dips. Energies, 10(9), 1441. doi:10.3390/en10091441Honrubia-Escribano, A., Jiménez-Buendía, F., Sosa-Avendaño, J. L., Gartmann, P., Frahm, S., Fortmann, J., … Gómez-Lázaro, E. (2019). Fault-Ride Trough Validation of IEC 61400-27-1 Type 3 and Type 4 Models of Different Wind Turbine Manufacturers. Energies, 12(16), 3039. doi:10.3390/en12163039Wang, L., Zhang, Z., Long, H., Xu, J., & Liu, R. (2017). Wind Turbine Gearbox Failure Identification With Deep Neural Networks. IEEE Transactions on Industrial Informatics, 13(3), 1360-1368. doi:10.1109/tii.2016.2607179Hansen, A. D., & Hansen, L. H. (2007). Wind turbine concept market penetration over 10 years (1995–2004). Wind Energy, 10(1), 81-97. doi:10.1002/we.210IEC 61400-27-1. Electrical Simulation Models—Wind Turbines; Technical Reporthttps://webstore.iec.ch/publication/21811Vázquez-Hernández, C., Serrano-González, J., & Centeno, G. (2017). A Market-Based Analysis on the Main Characteristics of Gearboxes Used in Onshore Wind Turbines. Energies, 10(11), 1686. doi:10.3390/en10111686Duong, M., Grimaccia, F., Leva, S., Mussetta, M., & Le, K. (2015). Improving Transient Stability in a Grid-Connected Squirrel-Cage Induction Generator Wind Turbine System Using a Fuzzy Logic Controller. Energies, 8(7), 6328-6349. doi:10.3390/en8076328Cheng, M., & Zhu, Y. (2014). The state of the art of wind energy conversion systems and technologies: A review. Energy Conversion and Management, 88, 332-347. doi:10.1016/j.enconman.2014.08.037Pinar Pérez, J. M., García Márquez, F. P., Tobias, A., & Papaelias, M. (2013). Wind turbine reliability analysis. Renewable and Sustainable Energy Reviews, 23, 463-472. doi:10.1016/j.rser.2013.03.018Sumathi, S., Ashok Kumar, L., & Surekha, P. (2015). Wind Energy Conversion Systems. Green Energy and Technology, 247-307. doi:10.1007/978-3-319-14941-7_4Fernández-Guillamón, A., Sarasúa, J. I., Chazarra, M., Vigueras-Rodríguez, A., Fernández-Muñoz, D., & Molina-García, Á. (2020). Frequency control analysis based on unit commitment schemes with high wind power integration: A Spanish isolated power system case study. International Journal of Electrical Power & Energy Systems, 121, 106044. doi:10.1016/j.ijepes.2020.106044Liu, J., Gao, Y., Geng, S., & Wu, L. (2017). Nonlinear Control of Variable Speed Wind Turbines via Fuzzy Techniques. IEEE Access, 5, 27-34. doi:10.1109/access.2016.2599542Margaris, I. D., Hansen, A. D., Sørensen, P., & Hatziargyriou, N. D. (2010). Illustration of Modern Wind Turbine Ancillary Services. Energies, 3(6), 1290-1302. doi:10.3390/en3061290Wan, S., Cheng, K., Sheng, X., & Wang, X. (2019). Characteristic Analysis of DFIG Wind Turbine under Blade Mass Imbalance Fault in View of Wind Speed Spatiotemporal Distribution. Energies, 12(16), 3178. doi:10.3390/en12163178Boukhezzar, B., & Siguerdidjane, H. (2011). Nonlinear Control of a Variable-Speed Wind Turbine Using a Two-Mass Model. IEEE Transactions on Energy Conversion, 26(1), 149-162. doi:10.1109/tec.2010.2090155Chu, Yuan, Hu, Pan, & Pan. (2019). Comparative Analysis of Identification Methods for Mechanical Dynamics of Large-Scale Wind Turbine. Energies, 12(18), 3429. doi:10.3390/en12183429Villena-Ruiz, R., Honrubia-Escribano, A., Fortmann, J., & Gómez-Lázaro, E. (2020). Field validation of a standard Type 3 wind turbine model implemented in DIgSILENT-PowerFactory following IEC 61400-27-1 guidelines. International Journal of Electrical Power & Energy Systems, 116, 105553. doi:10.1016/j.ijepes.2019.105553Ekanayake, J. 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Effect of the initial particle size distribution on the properties of suspension plasma sprayed Al2O3-TiO2 coatings

“NOTICE: this is the author’s version of a work that was accepted for publication in Surface & Coatings Technology. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Surface & Coatings Technology, [268 (2015) 209-215] DOI 10.1016/j.surfcoat.2014.12.010¨Al2O3-TiO2 coatings have been deposited by atmospheric plasma spraying from agglomerated, nanostructured powders showing better properties than those of their conventional (microstructured) counterparts. These nanostructured coatings can be also obtained by suspension plasma spraying however the research on suspension plasma sprayed Al2O3-TiO2 is still scarce. Consequently, it is crucial to study the effect of the suspension characteristics on the coating properties and to optimize the deposition process. In this work, Al2O3-13 wt.% TiO2 tribological coatings were successfully deposited by suspension plasma spraying from three different feedstocks: a nanometric suspension and two bimodal suspensions with different solid contents made up of titania nanoparticles and alumina submicron-sized particles. The coating microstructure and phase composition were characterized using scanning electron microscopy and X-ray diffraction analysis. Moreover, nanoindentation technique was used to determine the nanomechanical properties of coatings. The influence of the feed suspension characteristics on the final coating quality was analyzed. Findings showed that similar microstructures and phases were developed after depositing the different feedstocks. In addition suspension feedstock made up of nanoparticles resulted in a coating with better mechanical properties. However the use of submicron-sized particles in the suspension feedstocks gives rise to some technical and economic advantages in the process which should be taken into account when a suspension plasma spraying process is to be setup. (C) 2014 Elsevier B.V. All rights reserved.This work has been supported by the Spanish Ministry of Science and Innovation (project MAT2012-38364-C03) and it has been co-funded by ERDF (European Regional Development Funds).Vicent, M.; Bannier, E.; Carpio, P.; Rayón Encinas, E.; Benavente Martínez, R.; Salvador Moya, MD.; Sánchez, E. (2015). Effect of the initial particle size distribution on the properties of suspension plasma sprayed Al2O3-TiO2 coatings. Surface and Coatings Technology. 268:209-215. https://doi.org/10.1016/j.surfcoat.2014.12.010S20921526

Prognostic classification for malignant tumors of the parotid gland

AbstractObjectiveThe histological classification of the World Health Organization (WHO), along with improved imaging studies, provide relevant information for the management of parotid carcinomas. However, the prognosis depends on factors other than histology and tumor extension. This article evaluates the usefulness of a prognostic classification of parotid cancers, including these factors in patients in a hospital area.MethodsA follow-up was conducted on 19 patients with parotid carcinomas, excluding lymphoid tumors or intra-parotid metastases, between 1998 and 2012. The prognostic index was obtained from the formulas proposed by Vander Poorten, with factors including age, tumor size, lymph node involvement, skin invasion, facial nerve involvement, perineural growth and margins of resection, before surgery (PS1) and after (PS2). Overall survival was related to 5 years for each patient based on their inclusion in any of the 4 risk groups defined.ResultsRisk stratification based on the results Vander Poorten PS2 was distributed into Risk Groups (GR) 1 (3 patients, 15.7%), 2 (5 patients, 26.3%), 3 (1 patient, 5.8%) and 4 (10 patients, 52.2%). The 6 patients who died during follow-up belonged to GR4. Only one of the 4 patients belonging to GR4 has exceeded the 5-year survival up to the current time.The comparison of the values that relate the pretreatment (PS1) and after treatment (PS2) results showed overall survival in patients with PS1<4.5 and PS2<4.9, whereas mortality was greater with indices of PS1>6.5 and PS2>7.7.ConclusionsVander Poorten index can be applied in hospital areas with small numbers of parotid carcinomas. It enables a more accurate prognosis for individual patients

Lung Ultrasound, Clinical and Analytic Scoring Systems as Prognostic Tools in SARS-CoV-2 Pneumonia: A Validating Cohort

At the moment, several COVID-19 scoring systems have been developed. It is necessary to determine which one better predicts a poor outcome of the disease. We conducted a single-center prospective cohort study to validate four COVID-19 prognosis scores in adult patients with confirmed infection at ward. These are National Early Warning Score (NEWS) 2, Lung Ultrasound Score (LUS), COVID-19 Worsening Score (COWS), and Spanish Society of Infectious Diseases and Clinical Microbiology score (SEIMC Score). Our outcomes were the combined variable “poor outcome” (noninvasive mechanical ventilation, intubation, intensive care unit admission, and death at 28 days) and death at 28 days. Scores were analysed using univariate logistic regression models, receiver operating characteristic curves, and areas under the curve. Eighty-one patients were included, from which 21 had a poor outcome, and 9 died. We found a statistically significant correlation between poor outcome and NEWS2, LUS > 15, and COWS. Death at 28 days was statistically correlated with NEWS2 and SEIMC Score although COWS also performs well. NEWS2, LUS, and COWS accurately predict poor outcome; and NEWS2, SEIMC Score, and COWS are useful for anticipating death at 28 days. Lung ultrasound is a diagnostic tool that should be included in COVID-19 patients evaluation

Comparación de pacientes con lupus eritematoso sistémico tratados en centros públicos versus centros privados de salud

Estudios recientes sobre lupus eritematoso sistémico (LES) han comunicado desenlaces más favorables gracias al mejor conocimiento de la enfermedad, al manejo más experto del mismo y al uso racional de los tratamientos. En este estudio se identificaron 301 pacientes con lupus eritematoso sistémico (LES), vistos entre 1988 y 2019. Doscientos veintiocho fueron tratados en el sistema público de salud y 73 en el sistema privado. Ambos grupos fueron comparados, observando que los primeros tenían menor edad al momento de la primera consulta y al inicio del LES y menor tiempo de evolución hasta la primera consulta que los pacientes atendidos en el sistema privado de salud de manera estadísticamente significativa. También mostraron mayor frecuencia de leucopenia, con presencia de anticuerpo Sm y compromiso renal en la primera consulta, como así también mayor uso de corticoides EV. Los pacientes hospitalarios presentaron mayor daño acumulado en los primeros 10 años de evolución, pero el desenlace muerte fue similar en ambos grupos. Ambos grupos de pacientes (tanto los del sistema público como los del sector privado) fueron atendidos por especialistas, realizando un cuidadoso seguimiento de estos pacientes

Identification of Linearized RMS-Voltage Dip Patterns Based on Clustering in Renewable Plants

[EN] Generation units connected to the grid are currently required to meet low-voltage ride-through (LVRT) requirements. In most developed countries, these requirements also apply to renewable sources, mainly wind power plants and photovoltaic installations connected to the grid. This study proposes an alternative characterisation solution to classify and visualise a large number of collected events in light of current limits and requirements. The authors' approach is based on linearised root-mean-square-(RMS)-voltage trajectories, taking into account LRVT requirements, and a clustering process to identify the most likely pattern trajectories. The proposed solution gives extensive information on an event's severity by providing a simple but complete visualisation of the linearised RMS-voltage patterns. In addition, these patterns are compared to current LVRT requirements to determine similarities or discrepancies. A large number of collected events can then be automatically classified and visualised for comparative purposes. Real disturbances collected from renewable sources in Spain are used to assess the proposed solution. Extensive results and discussions are also included in this study.The authors thank the financial support from the 'Ministerio de Economia y Competitividad' (Spain) and the European Union - ENE2016-78214-C2-2-R, Fulbright/Spanish Ministry of Education Visiting Scholar - PRX14/00694. This work was also supported by the US Department of Energy under contract no. DE-AC36-08-GO28308 with the National Renewable Energy LaboratoryGarcía-Sánchez, TM.; Gómez-Lázaro, E.; Muljadi, E.; Kessler, M.; Muñoz-Benavente, I.; Molina-García, A. (2018). Identification of Linearized RMS-Voltage Dip Patterns Based on Clustering in Renewable Plants. IET Generation Transmission & Distribution. 12(6):1256-1262. https://doi.org/10.1049/iet-gtd.2017.0474S12561262126Craciun B. Kerekes T. 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Inibição do crescimento de bactérias Gram-negativas em microdiluição por tratamento com Nisina e EDTA

The outer membrane composition of Gram-negative bacteria provides more resistance against the action of antimicrobial agents from the class of bacteriocins, in comparison to Gram-positive bacteria, naturally more susceptible. Aiming the control of proliferation Escherichia coli, Pseudomonas aeruginosa and Salmonella Typhimurium, antimicrobial assays were performed with nisin as biocidal agent (concentrations 123 to 1,111 AU mL-1) and EDTA as chelating agent, compared to a Gram-positive (Staphylococcus aureus ATCC25923). The susceptibility evaluations were performed in broth microdilution with Mueller-Hinton medium and inoculum with 106 CFU mL-1 of indicator bacterium, and the results were obtained by optical density readings (630 nm) at regular intervals during the incubation period. It was observed that EDTA is capable of reducing cell viability of P. aeruginosa. The bacteriocin nisin demonstrated effective antimicrobial action to four indicator bacteria, under different concentrations. The combined treatments of nisin+EDTA obtained high inhibition rates, and the presence of EDTA was significant only to Gram-negative bacteria. Thus, treatments accounted effective strategies to promote inhibition of cell growth during microdilution broth assays.A composição da membrana externa das bactérias Gram-negativas fornece mais resistência à ação dos agentes antimicrobianos da classe das bacteriocinas, em comparação às bactérias Gram-positivas, naturalmente mais suscetíveis. Com o objetivo de controlar a proliferação de Escherichia coli, Pseudomonas aeruginosa e Salmonella Typhimurium, foram realizados ensaios antimicrobianos com nisina como agente biocida (concentrações 123 a 1.111 AU mL-1) e EDTA como agente quelante, comparado a um Gram-positivo (Staphylococcus aureus ATCC25923) . As avaliações de suscetibilidade foram realizadas em microdiluição em caldo com meio Mueller-Hinton e inóculo com 106 UFC-1 de bactéria indicadora, e os resultados foram obtidos por leituras de densidade óptica (630 nm) em intervalos regulares durante o período de incubação. Observou-se que o EDTA é capaz de reduzir a viabilidade celular de P. aeruginosa. A bacteriocina nisina demonstrou ação antimicrobiana eficaz para quatro bactérias indicadoras, sob diferentes concentrações. Os tratamentos combinados de nisina + EDTA obtiveram altas taxas de inibição e a presença de EDTA foi significativa apenas para bactérias Gram-negativas. Assim, os tratamentos representaram estratégias eficazes para promover a inibição do crescimento celular durante ensaios de caldo de microdiluição

Compétence en Technologie de l’Information Géographique (TIG) dans les études universitaires: réflexions et propositions participative

El objetivo de este trabajo es ofrecer una reflexión que conduzca a una asignación coherente de competencias en la enseñanza sobre Tecnologías de la Información Geográfica (Cartografía, Sistemas de Información Geográfica y Teledetección) que se imparte en la universidad. Tras analizar diversas propuestas al respecto, en España y a nivel internacional, y a través de una serie de talleres participativos, un grupo de académicos de la Universidad de Alcalá ha generado su propia propuesta sobre las competencias más importantes y necesarias a conseguir en cada nivel de la educación superior (grado, master y doctorado). La propuesta ha sido contrastada con los resultados de una encuesta realizada entre un conjunto de académicos universitarios españoles.The aim of this paper is to offer an insight on competences leading to their consistent allocation in the different courses on Geographic Information Technologies (Cartography, Geographic Information Systems - GIS and Remote Sensing) taught in universities. To do this, after analyzing the various proposals on the subject, both in Spain and internationally, and after conducting a series of participatory workshops, a group of academics from the University of Alcalá has generated its own proposal on the most important and necessary competences to acquire at each level of higher education (bachelor, master and doctorate). Furthermore, the proposal has been contrasted with the results of a survey conducted by a wide range of Spanish university academics.Le but de cet article est de proposer une réflexion conduisant à une allocation cohérente des compétences dans les différents cours sur les technologies d’information géographique (Cartographie, Système d’Information Géographique- SIG et télédétection) enseignées dans les universités. Pour ce faire, après avoir analysé les différentes propositions sur le sujet, à la fois en Espagne et à l’étranger, et après la réalisation d’une série d’ateliers participatifs, un groupe de l’Université de Alcalá a généré sa propre proposition sur les compétences les plus importants et nécessaires pour obtenir à chaque niveau de l’enseignement supérieur (licence, master et doctorat). En outre, la proposition a été contrastée avec les résultats d’une enquête menée par un large éventail d’universitaires espagnols