Construcciones simétricas con 2 y 3 años: La actividad matemática emergente del juego infantil

En esta experiencia de juego de construcción, en el grupo de 2-3 años de primer ciclo de educación infantil, proponemos un material de construcción diseñado para favorecer la actividad matemática en sesiones de juego libre. Junto a construcciones iniciales como los apilamientos y cerramientos, surgen las primeras construcciones simétricas. La actitud de escucha y la observación atenta de la actividad infantil sugieren pautas de intervención para favorecer el desarrollo del pensamiento matemático de los pequeños

Policy and Environmental Implications of Photovoltaic Systems in Farming in Southeast Spain: Can Greenhouses Reduce the Greenhouse Effect?

Solar photovoltaic (PV) systems have grown in popularity in the farming sector, primarily because land area and farm structures themselves, such as greenhouses, can be exploited for this purpose, and, moreover, because farms tend to be located in rural areas far from energy production plants. In Spain, despite being a country with enormous potential for this renewable energy source, little is being done to exploit it, and policies of recent years have even restricted its implementation. These factors constitute an obstacle, both for achieving environmental commitments and for socioeconomic development. This study proposes the installation of PV systems on greenhouses in southeast Spain, the location with the highest concentration of greenhouses in Europe. Following a sensitivity analysis, it is estimated that the utilization of this technology in the self-consumption scenario at farm level produces increased profitability for farms, which can range from 0.88% (worst scenario) to 52.78% (most favorable scenario). Regarding the Spanish environmental policy, the results obtained demonstrate that the impact of applying this technology mounted on greenhouses would bring the country 38% closer to reaching the 2030 greenhouse gas (GHG) target. Furthermore, it would make it possible to nearly achieve the official commitment of 20% renewable energies by 2020. Additionally, it would have considerable effects on the regional socioeconomy, with increases in job creation and contribution to gross domestic product (GDP)/R&D (Research and Development), allowing greater profitability in agrifood activities throughout the entire region

Participación del calcio en la ruta de señalización asociada a la deficiencia de boro en las raíces de "Arabidopsis thaliana"

Programa de Doctorado en Biotecnología y Tecnología Química1) INTRODUCCIÓN El boro (B) es un nutriente esencial para las plantas vasculares y tanto su deficiencia como su toxicidad afectan a numerosos procesos metabólicos y fisiológicos (Nable y col., 1997; Blevins y Lukaszewski, 1998; Bolaños y col., 2004; Reid, 2007; Camacho-Cristóbal y col., 2008; Herrera-Rodríguez y col., 2010; Martín-Rejano y col., 2011). El B, en forma de ácido bórico o borato, es capaz de formar complejos con una gran variedad de compuestos biológicos que contienen dos grupos hidroxilo en configuración cis. Una de las principales funciones del B en las plantas vasculares está relacionada con la pared celular, ya que se establecen enlaces éster entre el anión borato y los residuos de apiosa del ramnogalacturonano II (RGII); la construcción de este complejo es fundamental para la estructura y función de la pared celular (O¿Neill y col., 2004), y desempeña una función crítica en los tejidos en crecimiento. Entre el 80 y el 90% del B total presente en la planta se encuentra en las paredes celulares formando dímeros de RGII, siendo este complejo esencial para la estructura y función de la pared celular; por lo tanto, se puede decir que la principal función de este micronutriente es estructural (Blevins y Lukaszewski, 1998). La deficiencia en B no sólo tiene efectos sobre la estructura y función de la pared celular de las plantas vasculares sino que, además, influye sobre otros muchos procesos: metabolismo del ácido indolacético, translocación de azúcares, metabolismo de carbohidratos, síntesis de ácidos nucleicos, crecimiento del tubo polínico, potencial de membrana, enzimas del plasmalema, flujo de iones a través de las membranas, proteínas del citoesqueleto (Blevins y Lukaszewski, 1998; Bolaños y col., 2004; Goldbach y Wimmer, 2007), acumulación de compuestos fenólicos y poliaminas (Camacho-Cristóbal y col., 2002, 2004 y 2005), asimilación de nitrógeno (Camacho-Cristóbal y González-Fontes, 2007; Beato y col., 2010, 2011 y 2014), y desarrollo de la raíz (Martín-Rejano y col., 2011), entre otros. Aunque se desconoce el mecanismo molecular por el cual la planta es capaz de sentir la deficiencia de este micronutriente y desarrollar la respuesta fisiológica, recientemente se ha propuesto que el calcio podría estar directamente implicado en la transmisión de esta señal. Se conocen múltiples estreses bióticos y abióticos que afectan a la concentración de calcio citosólico, provocando ¿firmas de calcio¿ (Sanders y col., 2002; Hetherington y Brownlee, 2004), es decir, patrones espacio-temporales de cambio en los niveles de calcio que son específicos para cada estímulo. Estas ¿firmas de calcio¿ se deben a movimientos de calcio regulados mediante canales y bombas (Sanders y col., 2002; Hetherington y Brownlee, 2004; Bastistic y Kudla, 2012); posteriormente son percibidas, descodificadas y transmitidas mediante proteínas de unión a calcio, como: calmodulinas, proteínas similares a calmodulinas, quinasas dependientes de calcio y proteínas similares a calcineurina-B (Sanders y col., 2002; Hashimoto y Kudla, 2011). Cuando estas proteínas se unen al calcio, se activan interaccionando a su vez con otras proteínas; de esta manera, la información contenida en la ¿firma de calcio¿ es transmitida a través de eventos de fosforilación, cambios en las interacciones entre proteínas o mediante regulación transcripcional y, por lo tanto, induciendo las respuestas ante cada estrés. Se piensa que algunos de estos sensores de calcio podrían estar involucrados en la señal de deficiencia de B. 2) OBJETIVOS A pesar de que la deficiencia de B provoca múltiples efectos en la fisiología y bioquímica de las plantas vasculares, se desconoce el mecanismo a través del cual las plantas son capaces de sentir y transmitir esta señal. Recientemente se ha propuesto que el calcio (Ca2+) podría mediar en este proceso de señalización. Por tanto, los objetivos de esta investigación fueron determinar si hay una relación entre la deficiencia de B y la concentración de calcio citosólico ([Ca2+]cit), y si el Ca2+ participa en la transmisión de la señal de deficiencia de B en las raíces de Arabidopsis thaliana; también fue interesante determinar qué genes/proteínas participarían en esta señalización, así como estudiar la interacción con otros cationes, como el potasio. 3) METODOLOGÍA En un primer momento se estudió si la deficiencia de B a corto plazo afectaba a los niveles de expresión de genes relacionados con la señalización de calcio en las raíces de Arabidopsis. Con este fin, se cultivaron plántulas de la estirpe silvestre Col0 y se transfirieron a medios con suficiencia o deficiencia de B durante 6 y 24 horas, se tomaron muestras de raíces de las cuales se hizo una extracción de RNA y una posterior síntesis de cDNA para analizar los niveles de expresión mediante Q-RT-PCR. También se estudió el efecto de la adición al medio de reactivos que alteraran la disponibilidad de calcio para las plántulas, con el objetivo de determinar si había cambios en el patrón de expresión de los genes analizados. Posteriormente se analizó la actividad GUS bajo el control de varios promotores (pCML12::GUS, pCML24::GUS, pCPK28::GUS, pACA10::GUS y pMYB15::GUS) en raíces de plántulas de Arabidopsis que habían sido sometidas a deficiencia de B durante 6 y 24 horas, con el objetivo de confirmar los resultados obtenidos previamente. Al igual que antes, se repitieron los experimentos añadiendo diferentes reactivos a los medios de cultivo. A continuación, se estudió si el efecto de la deficiencia de B a corto plazo afectaba únicamente a la expresión génica o si también lo hacía sobre los niveles de proteínas en las raíces de Arabidopsis. Para ello se realizaron diferentes WESTERN-BLOTS para las proteínas: CAX3, CNGC19 y ACA10, usando para ello anticuerpos específicos contra cada una de ellas. El siguiente paso fue determinar si la deficiencia de B a corto plazo afectaba realmente a los niveles de calcio en plántulas de Arabidopsis.Universidad Pablo de Olavide. Departamento de Fisiología, Anatomía y Biología Celula

Accurate Sizing of Residential Stand-Alone Photovoltaic Systems Considering System Reliability

[EN] In rural areas or in isolated communities in developing countries it is increasingly common to install micro-renewable sources, such as photovoltaic (PV) systems, by residential consumers without access to the utility distribution network. The reliability of the supply provided by these stand-alone generators is a key issue when designing the PV system. The proper system sizing for a minimum level of reliability avoids unacceptable continuity of supply (undersized system) and unnecessary costs (oversized system). This paper presents a method for the accurate sizing of stand-alone photovoltaic (SAPV) residential generation systems for a pre-established reliability level. The proposed method is based on the application of a sequential random Monte Carlo simulation to the system model. Uncertainties of solar radiation, energy demand, and component failures are simultaneously considered. The results of the case study facilitate the sizing of the main energy elements (solar panels and battery) depending on the required level of reliability, taking into account the uncertainties that affect this type of facility. The analysis carried out demonstrates that deterministic designs of SAPV systems based on average demand and radiation values or the average number of consecutive cloudy days can lead to inadequate levels of continuity of supply.This work has been supported by research funds of the Universitat Politecnica de Valencia.Quiles Cucarella, E.; Roldán-Blay, C.; Escrivá-Escrivá, G.; Roldán-Porta, C. (2020). Accurate Sizing of Residential Stand-Alone Photovoltaic Systems Considering System Reliability. Sustainability. 12(3):1-18. https://doi.org/10.3390/su12031274S118123Twaha, S., & Ramli, M. A. M. (2018). A review of optimization approaches for hybrid distributed energy generation systems: Off-grid and grid-connected systems. Sustainable Cities and Society, 41, 320-331. doi:10.1016/j.scs.2018.05.027Mandelli, S., Barbieri, J., Mereu, R., & Colombo, E. (2016). Off-grid systems for rural electrification in developing countries: Definitions, classification and a comprehensive literature review. Renewable and Sustainable Energy Reviews, 58, 1621-1646. doi:10.1016/j.rser.2015.12.338Luthander, R., Widén, J., Nilsson, D., & Palm, J. (2015). Photovoltaic self-consumption in buildings: A review. Applied Energy, 142, 80-94. doi:10.1016/j.apenergy.2014.12.028Evans, A., Strezov, V., & Evans, T. J. (2012). Assessment of utility energy storage options for increased renewable energy penetration. Renewable and Sustainable Energy Reviews, 16(6), 4141-4147. doi:10.1016/j.rser.2012.03.048https://www.boe.es/diario_boe/txt.php?id=BOE-A-2019-5089Bugała, A., Zaborowicz, M., Boniecki, P., Janczak, D., Koszela, K., Czekała, W., & Lewicki, A. (2018). Short-term forecast of generation of electric energy in photovoltaic systems. Renewable and Sustainable Energy Reviews, 81, 306-312. doi:10.1016/j.rser.2017.07.032Abuagreb, M., Allehyani, M., & Johnson, B. K. (2019). Design and Test of a Combined PV and Battery System Under Multiple Load and Irradiation Conditions. 2019 IEEE Power & Energy Society Innovative Smart Grid Technologies Conference (ISGT). doi:10.1109/isgt.2019.8791565Moharil, R. M., & Kulkarni, P. S. (2010). Reliability analysis of solar photovoltaic system using hourly mean solar radiation data. Solar Energy, 84(4), 691-702. doi:10.1016/j.solener.2010.01.022Dissawa, D. M. L. H., Godaliyadda, G. M. R. I., Ekanayake, M. P. B., Ekanayake, J. B., & Agalgaonkar, A. P. (2017). Cross-correlation based cloud motion estimation for short-term solar irradiation predictions. 2017 IEEE International Conference on Industrial and Information Systems (ICIIS). doi:10.1109/iciinfs.2017.8300338Kaplani, E., & Kaplanis, S. (2012). A stochastic simulation model for reliable PV system sizing providing for solar radiation fluctuations. Applied Energy, 97, 970-981. doi:10.1016/j.apenergy.2011.12.016Benmouiza, K., Tadj, M., & Cheknane, A. (2016). Classification of hourly solar radiation using fuzzy c-means algorithm for optimal stand-alone PV system sizing. International Journal of Electrical Power & Energy Systems, 82, 233-241. doi:10.1016/j.ijepes.2016.03.019Ozoegwu, C. G. (2019). Artificial neural network forecast of monthly mean daily global solar radiation of selected locations based on time series and month number. Journal of Cleaner Production, 216, 1-13. doi:10.1016/j.jclepro.2019.01.096Palensky, P., & Dietrich, D. (2011). Demand Side Management: Demand Response, Intelligent Energy Systems, and Smart Loads. IEEE Transactions on Industrial Informatics, 7(3), 381-388. doi:10.1109/tii.2011.2158841Roldán-Blay, C., Escrivá-Escrivá, G., & Roldán-Porta, C. (2019). Improving the benefits of demand response participation in facilities with distributed energy resources. Energy, 169, 710-718. doi:10.1016/j.energy.2018.12.102Roldán-Porta, Roldán-Blay, Escrivá-Escrivá, & Quiles. (2019). Improving the Sustainability of Self-Consumption with Cooperative DC Microgrids. Sustainability, 11(19), 5472. doi:10.3390/su11195472Huang, Y., Yang, L., Liu, S., & Wang, G. (2018). Cooperation between Two Micro-Grids Considering Power Exchange: An Optimal Sizing Approach Based on Collaborative Operation. Sustainability, 10(11), 4198. doi:10.3390/su10114198Goel, S., & Sharma, R. (2017). Performance evaluation of stand alone, grid connected and hybrid renewable energy systems for rural application: A comparative review. Renewable and Sustainable Energy Reviews, 78, 1378-1389. doi:10.1016/j.rser.2017.05.200Weniger, J., Tjaden, T., & Quaschning, V. (2014). Sizing of Residential PV Battery Systems. Energy Procedia, 46, 78-87. doi:10.1016/j.egypro.2014.01.160Maleki, A., Rosen, M., & Pourfayaz, F. (2017). Optimal Operation of a Grid-Connected Hybrid Renewable Energy System for Residential Applications. Sustainability, 9(8), 1314. doi:10.3390/su9081314Cao, S., Hasan, A., & Sirén, K. (2014). Matching analysis for on-site hybrid renewable energy systems of office buildings with extended indices. Applied Energy, 113, 230-247. doi:10.1016/j.apenergy.2013.07.031Ren, H., Wu, Q., Gao, W., & Zhou, W. (2016). Optimal operation of a grid-connected hybrid PV/fuel cell/battery energy system for residential applications. Energy, 113, 702-712. doi:10.1016/j.energy.2016.07.091Ghafoor, A., & Munir, A. (2015). Design and economics analysis of an off-grid PV system for household electrification. Renewable and Sustainable Energy Reviews, 42, 496-502. doi:10.1016/j.rser.2014.10.012Maleki, A., Hajinezhad, A., & Rosen, M. A. (2016). Modeling and optimal design of an off-grid hybrid system for electricity generation using various biodiesel fuels: a case study for Davarzan, Iran. Biofuels, 7(6), 699-712. doi:10.1080/17597269.2016.1192443Castillo-Cagigal, M., Caamaño-Martín, E., Matallanas, E., Masa-Bote, D., Gutiérrez, A., Monasterio-Huelin, F., & Jiménez-Leube, J. (2011). PV self-consumption optimization with storage and Active DSM for the residential sector. Solar Energy, 85(9), 2338-2348. doi:10.1016/j.solener.2011.06.028Zhou, W., Lou, C., Li, Z., Lu, L., & Yang, H. (2010). Current status of research on optimum sizing of stand-alone hybrid solar–wind power generation systems. Applied Energy, 87(2), 380-389. doi:10.1016/j.apenergy.2009.08.012Yadav, A. K., & Chandel, S. S. (2014). Solar radiation prediction using Artificial Neural Network techniques: A review. Renewable and Sustainable Energy Reviews, 33, 772-781. doi:10.1016/j.rser.2013.08.055Roldán-Blay, C., Escrivá-Escrivá, G., Roldán-Porta, C., & Álvarez-Bel, C. (2017). An optimisation algorithm for distributed energy resources management in micro-scale energy hubs. Energy, 132, 126-135. doi:10.1016/j.energy.2017.05.038Hoevenaars, E. J., & Crawford, C. A. (2012). Implications of temporal resolution for modeling renewables-based power systems. Renewable Energy, 41, 285-293. doi:10.1016/j.renene.2011.11.013Cao, S., & Sirén, K. (2014). Impact of simulation time-resolution on the matching of PV production and household electric demand. Applied Energy, 128, 192-208. doi:10.1016/j.apenergy.2014.04.075Cucchiella, F., D’Adamo, I., Gastaldi, M., & Stornelli, V. (2018). Solar Photovoltaic Panels Combined with Energy Storage in a Residential Building: An Economic Analysis. Sustainability, 10(9), 3117. doi:10.3390/su10093117Kosmadakis, I., Elmasides, C., Eleftheriou, D., & Tsagarakis, K. (2019). 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Improving the Sustainability of Self-Consumption with Cooperative DC Microgrids

[EN] The development of microgrids is of great interest to facilitate the integration of distributed generation in electricity networks, improving the sustainability of energy production. Microgrids in DC (DC-MG) provide advantages for the use of some types of renewable generation and energy storage systems, such as batteries. In this article, a possible practical implementation of an isolated DC-MG for residential use with a cooperative operation of the different nodes is proposed. The main criterion is to achieve a very simple design with only primary control in a residential area. This application achieves a simple system, with low implementation costs, in which each user has autonomy but benefits from the support of the other users connected to the microgrid, which improves its reliability. The description of the elements necessary to create this cooperative system is one of the contributions of the work. Another important contribution is the analysis of the operation of the microgrid as a whole, where each node can be, arbitrarily, a consumer or an energy generator. The proposed structures could promote the use of small distributed generation and energy storage systems as the basis for a new paradigm of a more sustainable electricity grid of the future.This work has been partially supported by funds for research support of the Universitat Politècnica de ValènciaRoldán-Porta, C.; Roldán-Blay, C.; Escrivá-Escrivá, G.; Quiles Cucarella, E. (2019). Improving the Sustainability of Self-Consumption with Cooperative DC Microgrids. Sustainability. 11(19):1-22. https://doi.org/10.3390/su11195472S1221119Justo, J. J., Mwasilu, F., Lee, J., & Jung, J.-W. (2013). AC-microgrids versus DC-microgrids with distributed energy resources: A review. Renewable and Sustainable Energy Reviews, 24, 387-405. doi:10.1016/j.rser.2013.03.067Farhangi, H. (2010). The path of the smart grid. 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IEEE Power and Energy Magazine, 8(2), 41-48. doi:10.1109/mpe.2009.935557Hatziargyriou, N., Asano, H., Iravani, R., & Marnay, C. (2007). Microgrids. IEEE Power and Energy Magazine, 5(4), 78-94. doi:10.1109/mpae.2007.376583Papadimitriou, C. N., Zountouridou, E. I., & Hatziargyriou, N. D. (2015). Review of hierarchical control in DC microgrids. Electric Power Systems Research, 122, 159-167. doi:10.1016/j.epsr.2015.01.006Paska, J., Biczel, P., & Kłos, M. (2009). Hybrid power systems – An effective way of utilising primary energy sources. Renewable Energy, 34(11), 2414-2421. doi:10.1016/j.renene.2009.02.018Salomonsson, D., & Sannino, A. (2007). Low-Voltage DC Distribution System for Commercial Power Systems With Sensitive Electronic Loads. IEEE Transactions on Power Delivery, 22(3), 1620-1627. doi:10.1109/tpwrd.2006.883024Brenna, M., Foiadelli, F., Longo, M., & Abegaz, T. (2016). Integration and Optimization of Renewables and Storages for Rural Electrification. Sustainability, 8(10), 982. doi:10.3390/su8100982Khalid, M., Ahmadi, A., Savkin, A. V., & Agelidis, V. G. (2016). Minimizing the energy cost for microgrids integrated with renewable energy resources and conventional generation using controlled battery energy storage. Renewable Energy, 97, 646-655. doi:10.1016/j.renene.2016.05.042Mahdavyfakhr, M., Rashidirad, N., Hamzeh, M., Sheshyekani, K., & Afjei, E. (2017). Stability improvement of DC grids involving a large number of parallel solar power optimizers: An active damping approach. Applied Energy, 203, 364-372. doi:10.1016/j.apenergy.2017.06.044Lazzari, R., Piegari, L., Grillo, S., Carminati, M., Ragaini, E., Bossi, C., & Tironi, E. (2018). Selectivity and security of DC microgrid under line-to-ground fault. Electric Power Systems Research, 165, 238-249. doi:10.1016/j.epsr.2018.09.001Salomonsson, D., Soder, L., & Sannino, A. (2009). Protection of Low-Voltage DC Microgrids. IEEE Transactions on Power Delivery, 24(3), 1045-1053. doi:10.1109/tpwrd.2009.2016622Shuai, Z., Fang, J., Ning, F., & Shen, Z. J. (2018). Hierarchical structure and bus voltage control of DC microgrid. Renewable and Sustainable Energy Reviews, 82, 3670-3682. doi:10.1016/j.rser.2017.10.096Van den Broeck, G., Stuyts, J., & Driesen, J. (2018). A critical review of power quality standards and definitions applied to DC microgrids. Applied Energy, 229, 281-288. doi:10.1016/j.apenergy.2018.07.058Anand, S., Fernandes, B. G., & Guerrero, J. (2013). Distributed Control to Ensure Proportional Load Sharing and Improve Voltage Regulation in Low-Voltage DC Microgrids. IEEE Transactions on Power Electronics, 28(4), 1900-1913. doi:10.1109/tpel.2012.2215055Radwan, A. A. A., & Mohamed, Y. A.-R. I. (2012). Linear Active Stabilization of Converter-Dominated DC Microgrids. IEEE Transactions on Smart Grid, 3(1), 203-216. doi:10.1109/tsg.2011.2162430Che, Y., Zhou, J., Lin, T., Li, W., & Xu, J. (2018). 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Smart Cooperative Energy Supply Strategy to Increase Reliability in Residential Stand-Alone Photovoltaic Systems

[EN] In reliability studies of isolated energy supply systems for residential buildings, supply failures due to insufficient generation are generally analysed. Recent studies conclude that this kind of analysis makes it possible to optimally design the sizes of the elements of the generation system. However, in isolated communities or rural areas, it is common to find groups of dwellings in which micro-renewable sources, such as photovoltaic (PV) systems, can be installed. In this situation, the generation and storage of several houses can be considered as an interconnected system forming a cooperative microgrid (CoMG). This work analyses the benefits that sharing two autonomous installations can bring to each one, from the point of view of reliability. The method consists of the application of a random sequential Monte Carlo (SMC) simulation to the CoMG to evaluate the impact of a simple cooperative strategy on the reliability of the set. The study considers random failures in the generation systems. The results show that the reliability of the system increases when cooperation is allowed. Additionally, at the design stage, this allows more cost-effective solutions than single sizing with a similar level of reliability.This work was supported by Conselleria de Educacion, Investigacion, Cultura y Deporte (Grant No. AICO/2019/001).Roldán-Blay, C.; Roldán-Porta, C.; Quiles Cucarella, E.; Escrivá-Escrivá, G. (2021). Smart Cooperative Energy Supply Strategy to Increase Reliability in Residential Stand-Alone Photovoltaic Systems. Applied Sciences. 11(24):1-19. https://doi.org/10.3390/app112411723S119112

Particle Swarm Optimization Method for Stand-Alone Photovoltaic System Reliability and Cost Evaluation Based on Monte Carlo Simulation

[EN] In rural regions with limited access to the power grid, self-reliance for electricity generation is paramount. This study focuses on enhancing the design of stand-alone photovoltaic installations (SAPV) to replace conventional fuel generators thanks to the decreasing costs of PV modules and batteries. This study presents a particle swarm optimization (PSO) method for the reliable and cost-effective sizing of SAPV systems. The proposed method considers the variability of PV generation and domestic demand and optimizes the system design to minimize the total cost of ownership while ensuring a high level of reliability. The results show that for the PSO method with 500 iterations, the error is around 2%, and the simulation time is approximately 2.25 s. Moreover, the PSO method allows a much lower number of iterations to be used in the Monte Carlo simulation, with a total of 100 iterations used to obtain the averaged results. The optimization results, encompassing installed power, battery capacity, reliability, and annual costs, reveal the effectiveness of our approach. Notably, our discretized PSO algorithm converges, yielding specific parameters like 9900 W of installed power and a battery configuration of five 3550 Wh units for the case study under consideration. In summary, our work presents an efficient SAPV system design methodology supported by concrete numerical outcomes, considering supply reliability and installation and operational costs.Vicerrectorado de Investigacion de la Universitat Politecnica de Valencia (PAID-11-22)Quiles Cucarella, E.; Marquina-Tajuelo, A.; Roldán-Blay, C.; Roldán-Porta, C. (2023). Particle Swarm Optimization Method for Stand-Alone Photovoltaic System Reliability and Cost Evaluation Based on Monte Carlo Simulation. Applied Sciences. 13(21). https://doi.org/10.3390/app132111623132

Alternative intraoral donor sites to the chin and mandibular body-ramus

Provide a review of alternative intraoral donor sites to the chin and body-ramus of the mandible that bring fewer complications and that may be used to regenerate small and medium defects. A review was conducted using the search engine PUBMED and looking manually into scientific journals. From the 35 articles included, 6 corresponded to the coronoids, 3 corresponded to the zygomatic body, 5 corresponded to the anterior maxillary sinus wall, 3 corresponded to the zygomatic alveolar process, 2 corresponded to the incisive fossa, 2 corresponded to the anterior nasal spine, 2 corresponded to the palatal region, 5 corresponded to the tuberosity, and 7 corresponded to the palatal and mandibular tori. Although there are few complications described when using alternative intraoral donor sites, the main problem with these types of grafts is their scarce bone volume, with only the zygomatic body, anterior sinus wall, and palate sites being able to be used in medium defects. More clinical trials are necessary in order to evaluate the behavior of the alternative donor sites over time

Ahogamiento en agua dulce y salada en el H.U. San Juan de Alicante: Estudio de 15 años

Introducción y objetivos: En la actualidad, el ahogamiento se considera una de las principales causas de muerte accidental a nivel mundial. Las series publicadas acerca del ahogamiento en agua dulce y salada son escasas y existen pocos datos al respecto en España. Nuestro objetivo es valorar los casos de ahogamiento atendidos en nuestro Departamento de Salud, evaluando su comportamiento clínico y fisiopatológico, así como estudiar la influencia de los corticoides sobre el curso de la enfermedad. Material y métodos: Se analizaron retrospectivamente durante un período de 15 años todos los casos de ahogamiento ingresados en el Hospital Universitario San Juan de Alicante, situado en un área mediterránea. Comparamos las variables clínicas y analíticas entre la aspiración en agua dulce y salada y obtuvimos correlaciones entre la edad, el sexo, la necesidad de resucitación y el nivel de conciencia. Además, se comparó la analítica sanguínea, gasometría arterial, radiología, estancia media hospitalaria, evolución clínica, tratamiento y pronóstico según el lugar del ahogamiento. Resultados: Se estudiaron 77 hombres (71%) y 32 mujeres (29%), con una edad media de 51 ± 27 años. Los pacientes fueron divididos en: grupo A) agua salada (72%) y grupo B) agua dulce (28%). Se encontraron diferencias estadísticas en la edad (A: 57 ± 22 vs B: 35 ± 33, p <0,001), hemoglobina (A: 15 ± 2 vs B: 13 ± 2, p<0,002), hematocrito (A: 45 ± 8 vs B: 40 ± 5, p<0,001), pH (A: 7,2 ± 0,2 vs B: 7,3 ± 0,1, p<0,001), HCO3 (A: 16 ± 6 vs B: 21 ± 5, p<0,001), PaO2/FiO2 (A: 316 ± 148 vs B: 223 ± 98, p<0,034) y RCP por Equipo de Emergencias (A: 23% vs B: 45%, p<0,039). No se observaron diferencias en el patrón radiológico, siendo el más frecuente el alveolar difuso bilateral (44%). No hubo diferencias significativas en las complicaciones excepto en el SDRA (A: 1% vs B: 10%, p<0,035); a destacar la neumonía bacteriana que fue ligeramente más frecuente en el grupo A (15% vs B: 13%). Fueron ingresados directamente en UCI 43 pacientes, de los cuales 19 (44%) precisaron ventilación mecánica, 26 (60%) antibioterapia y 20 (47%) corticoides, observándose, en estos últimos, una tendencia a la reducción de la estancia media en UCI, aunque la estancia media total hospitalaria no mostró diferencias. Dos pacientes murieron y 4 desarrollaron daño neurológico permanente. Conclusiones: En nuestra serie la morbilidad y mortalidad de los que llegan al hospital con ahogamiento fue baja, siendo más frecuente en agua salada. Los esteroides podrían reducir el tiempo de hospitalización en UCI, pero no parecen modificar significativamente la estancia hospitalaria total.Introduction and objectives: Nowadays, drowning is considered one of the world´s leading accidental causes of death. The published studies about freshwater and saltwater drowning are rare and there are a few data in this regard in Spain. The objective of this project is to assess the drowning cases attended in our Health Department, evaluating their clinical and physiopathological behaviour and studying the corticosteroids influence in the disease course. Materials and methods: During a period of 15 years, all the admitted drowning cases in the Hospital of San Juan, placed in a Mediterranean area, were analyzed. We compared the clinical and analytical variables between freshwater and saltwater inhalation, getting correlations between age, gender, resuscitation necessity and conscience level. Moreover, blood test, arterial gasometry, radiology, average hospital stay, clinic evolution, treatment and prognosis were compared depending on the drowning place. Results: For this study 77 men (71%) and 32 women (29%) cases were analyzed, with an average age of 51 土 27. Patients were divided in two groups: Group A) saltwater (72%) and group B) freshwater (28%). Statistic differences were found in ages (A: 57 ± 22vs B: 35 ± 33, p <0,001), hemoglobin (A: 15 ± 2 vs B: 13 ± 2, p<0,002), hematocrit (A: 45 ± 8 vs B: 40 ± 5, p<0,001), pH (A: 7,2 ± 0,2 vs B: 7,3 ± 0,1, p<0,001), HCO3 (A: 16 ± 6 vs B:21 ± 5, p<0,001), PaO2/FiO2 (A: 316 ± 148 vs B: 223 ± 98, p<0,034), CPR by emergency health workers (A: 23% vs B: 45%, p<0,039). There were no differences in the radiological pattern, being the most common one the bilateral diffuse alveolar (44%). There weren't any meaningful differences in complications except for the ARDS (A:1% vs B:10%, p<0,035); remarking the bacterial pneumonia being slightly more frequent in group A (15% vs B: 13%). There were 43 patients who were directly admitted in the ICU, 19 of which (44%) needed mechanical ventilation (respiratory support), 26 (60%) antibiotic therapy and 20 (47%) corticoids, noticing a tendency to reduction in the average ICU stay in the last group, even though the average hospital stay showed no difference. Two patients died and 4 developed permanent neurological damage. Conclusions: This study shows the low morbidity and mortality of the people who arrived at the hospital with drowning, being more frequent in saltwater. Corticoids could reduce hospitalization stay in the ICU but show no significant modifications in the total hospitalization stay

ADQPCI: Data Acquisition Board for Educational purposes

En este trabajo se presenta una de las placas de adquisición de datos que se ha desarrollado con fines docentes para su utilización en prácticas relacionadas con sistemas en tiempo real e informática industrial y se plantean algunas de las ventajas e inconvenientes frente a la utilización de placas comerciales. A lo largo del trabajo se detalla el diseño del hardware, en el que se ha priorizado la facilidad de programación, siendo ésta una de las ventajas frente a las placas comerciales. En estas prácticas es fundamental que el alumno tome conciencia de la importancia de la interfaz hardware-software, si se quiere conseguir un sistema fiable y que explote al máximo las características del hardware. Con el desarrollo de una placa de adquisición de datos se consigue un sistema que el alumno puede utilizar en varias asignaturas de su titulación que están relacionadas con el desarrollo y programación de sistemas empotrados.In this work a data acquisition board developed for educational use in subjects related to real-time systems and industrial computing, is presented. The main advantages and disadvantages of using these boards versus the use of commercial boards are discussed. The hardware design described along this work emphasizes the facility of programming the board, which is one of the main advantages versus the commercial boards. In these practices it is essential that student comprehend the importance of the hardware-software interface in order to obtain a reliable system which exploits in a maximum way the characteristics of the hardware. The development of a data acquisition board allows to obtain a system that the students can use in several course during his university career which are related to the development and programming of embedded system