Viabilidad del uso de la radiación solar concentrada al proceso de sinterización de cobre

En la actualidad, el proceso de sinterizado, así como la práctica totalidad de los procesos que se llevan a cabo en la industria, depende de las energías convencionales. Este trabajo pretende demostrar la viabilidad del uso de una fuente de energía renovable como es la Energía Solar Térmica en el sinterizado de cobre. Con objeto de realizar en el futuro una evaluación de las fuerzas conductoras y de la trayectoria del material transportado en función de las características del sistema y de la radicación incidente, se opta por diseñar distintos dispositivos experimentales de empaquetamiento basados en modelos de partículas ideales, en este caso cilindros, con los que se pretende simplificar la geometría del sistema real basado en partículas compactadas, siendo evaluados experimentalmente en el Homo Solar de la Plataforma Solar de Almería. Las muestras tratadas en atmósferas ligeramente reductoras, desarrollan cuellos bien definidos y muestran una reducción de porosidad, lo que permite demostrar la viabilidad del proceso

Information and digital technologies of Industry 4.0 and Lean supply chain management: a systematic literature review

The purpose of this paper is to provide an overview of the current state of research and the key aspects and implications of the relationships between Information and Digital Technologies (IDT) of Industry 4.0 and Lean Supply Chain Management (LSCM), with the identification of the lines of research developed and an analysis of the main findings. A Systematic Literature Review methodology has been used for the identification, selection, and evaluation of the published research. A set of 78 papers deduced from the most relevant scientific databases, including Web of Science, Scopus, and ABI/Inform, from 1996 to December 2019, has been analyzed and synthesized. The analysis and evaluation of these papers has enabled a new classification of the literature to be offered that identifies four lines of research based on the Life Cycle of Technology: obsolete IDT in LSCM; mature IDT in LSCM; emerging IDT in LSCM; and an Information Systems and IDT general approach in LSCM. The paper goes on to discuss the gaps found in the literature and proposes new opportunities and challenges for future research. A series of implications are presented intended to be useful from not only an academic point-of-view but also from a management focus, including recommendations for industrial managers and policymakers

Development and preliminary results of a mobile application to perform pre-inspection of sprayer equipment

Por todos es conocido que el presente y futuro de las aplicaciones de productos agroquímicos pasa por una buena regulación, calibración y mantenimiento de los equipos que se utilizan. Tanto Europa como los países miembros y sus comunidades autónomas, en el caso de España, a través de sus instituciones (Universidades, Consejerías, etc.), están trabajando concienzudamente en el protocolo de inspección. Es de prever que en muchos equipos la primera inspección será desfavorable, y además supondrá un coste económico alto para el propietario, independientemente de que el equipo pase la inspección de forma favorable o no. Este hecho hace que el agricultor no conciba este control con la “percepción beneficiosa” que pueda tener la administración. Por todo ello, el Laboratorio de Agricultura de Precisión de la Universidad de Sevilla ha decidido centrarse en el término “pre-inspección” y desarrollar una aplicación gratuita de autocontrol para dispositivos móviles que permita al propietario o su técnico agrícola conocer el estado de su equipo de aplicación antes de acudir a una inspección “oficial” y de esta forma solventar los posibles problemas detectados. En los primeros equipos que han formado parte de este estudio se ha conseguido, por una parte poner en conocimiento y mostrar los elementos y aspectos a controlar y por otra, generar de forma gratuita y fácil un informe donde se indica los elementos y aspectos a solventar antes de ir a una inspección. Esta aplicación de pre-inspección ha sido una herramienta muy valorada por los usuarios como mantenimiento preventivo.It is widely acknowledged that the present and future practice of pesticide applications requires good regulation, calibration and maintenance of the equipment used. European countries and their regional governments, in the case of Spain, through its institutions (Universities, Councils, etc.), are working conscientiously towards inspection protocol. It is expected that many sprayers will not pass the first inspection, and there will be a significant cost to the owner, whether the equipment passes the inspection or not. This fact makes this inspection protocol is not conceived with the “beneficial perception” as the administration may have. Therefore, the Precision Agriculture Laboratory at University of Sevilla has decided to focus on the term “pre-inspection” and develop a free mobile application for self-assessment that allows the owner or agricultural technician check the status of the sprayer before inspection. This would address the possible problem idenfified. For the first spayers considered in this study there have been several achievements: firstly informing about and showing those elements and aspects of the sprayer which need to be controlled and secondly, generating simply and without cost a report describing those elements and aspects which must be resolved before going for an inspection. This approach to pre-inspection has proved to be highly very valued by users as a tool for preventive maintenance

On the feasibility of predicting volumes of fake news- the Spanish case

The growing amount of news shared on the Internet makes it hard to verify them in real-time. Malicious actors take advantage of this situation by spreading fake news to impact society through misinformation. An estimation of future fake news would help to focus the detection and verification efforts. Unfortunately, no previous work has addressed this issue yet. Therefore, this work measures the feasibility of predicting the volume of future fake news in a particular context—Spanish contents related to Spain. The approach involves different artificial intelligence (AI) mechanisms on a dataset of 298k real news and 8.9k fake news in the period 2019–2022. Results show that very accurate predictions can be reached. In general words, the use of long short-term memory (LSTM) with attention mechanisms offers the best performance, being headlines useful when a small amount of days is taken as input. In the best cases, when predictions are made for periods, an error of 10.3% is made considering the mean of fake news. This error raises to 28.7% when predicting a single day in the future.This work was supported in part by the Universidad Carlos III de Madrid (UC3M) and the Government of Madrid [Community of Madrid (CAM)] under Grant DEPROFAKE-CM-UC3M; in part by the CAM through the Project CYNAMON, co-funded by the European Research Development Fund (ERDF), under Grant P2018/TCS-4566-CM; and in part by the Spanish Ministry of Science and Innovation (MICINN) of Spain under Grant PID2019-111429RB-C2

Study of fishmeal substitution on growth performance and shelf-life of giltheadsea bream (Sparusaurata)

[EN] In this work the effect of partial or total replacement of fishmeal by plant protein sources and krill and squid meal on growth performance and shelf-life of gilthead sea bream was evaluated. Plant protein dietswith 50 g kg(-1) of krill and 100 g kg(-1) of squid were supplemented with synthetic amino acidsand at the end of the growing period weight showed no significant differences. The spoilage process of the fish was followed by physicochemical and microbiological measurements together with a colorimetric sensor array (CSA) specially designed for that purpose. The changes in the physicochemical parameters and microbial growth showed that shelf-life of samples were in all cases lower than ninedays. The CSA was not able to show significant differences between both diets, confirming the physicochemical and microbiological results. The fact that the type of feed had no effect on the freshness parameters studied demonstrates that total fishmeal replacement with plant protein blends in the proportions used in this work could be an excellent alternative for feed formulation in aquaculture.We thanks to the financial support of the Universitat Politecnica de Valencia, Spain.Zaragozá, P.; Martínez-Llorens, S.; Fernández Segovia, I.; Vivancos, J.; Tomas-Vidal, A.; Fuentes López, A.; Ros-Lis, JV.... (2020). Study of fishmeal substitution on growth performance and shelf-life of giltheadsea bream (Sparusaurata). Fishes. 5(2):1-14. https://doi.org/10.3390/fishes5020015S11452Grigorakis, K. (2007). Compositional and organoleptic quality of farmed and wild gilthead sea bream (Sparus aurata) and sea bass (Dicentrarchus labrax) and factors affecting it: A review. Aquaculture, 272(1-4), 55-75. doi:10.1016/j.aquaculture.2007.04.062Martínez-Llorens, S., Moñino, A. V., Tomás Vidal, A., Salvador, V. J. M., Pla Torres, M., & Jover Cerdá, M. (2007). Soybean meal as a protein source in gilthead sea bream (Sparus aurata L.) diets: effects on growth and nutrient utilization. Aquaculture Research, 38(1), 82-90. doi:10.1111/j.1365-2109.2006.01637.xSánchez Lozano, N. B., Tomás Vidal, A., Martínez-Llorens, S., Nogales Mérida, S., Blanco, J. E., Moñino López, A., … Cerdá, M. J. (2007). Growth and economic profit of gilthead sea bream (Sparus aurata, L.) fed sunflower meal. Aquaculture, 272(1-4), 528-534. doi:10.1016/j.aquaculture.2007.07.221Martínez-Llorens, S., Baeza-Ariño, R., Nogales-Mérida, S., Jover-Cerdá, M., & Tomás-Vidal, A. (2012). Carob seed germ meal as a partial substitute in gilthead sea bream (Sparus aurata) diets: Amino acid retention, digestibility, gut and liver histology. Aquaculture, 338-341, 124-133. doi:10.1016/j.aquaculture.2012.01.029Sánchez-Lozano, N. B., Martínez-Llorens, S., Tomás-Vidal, A., & Cerdá, M. J. (2009). Effect of high-level fish meal replacement by pea and rice concentrate protein on growth, nutrient utilization and fillet quality in gilthead seabream (Sparus aurata, L.). Aquaculture, 298(1-2), 83-89. doi:10.1016/j.aquaculture.2009.09.028Estruch, G., Tomás-Vidal, A., El Nokrashy, A. M., Monge-Ortiz, R., Godoy-Olmos, S., Jover Cerdá, M., & Martínez-Llorens, S. (2018). Inclusion of alternative marine by-products in aquafeeds with different levels of plant-based sources for on-growing gilthead sea bream (Sparus aurata, L.): effects on digestibility, amino acid retention, ammonia excretion and enzyme activity. Archives of Animal Nutrition, 72(4), 321-339. doi:10.1080/1745039x.2018.1472408Monge-Ortiz, R., Martínez-Llorens, S., Márquez, L., Moyano, F. J., Jover-Cerdá, M., & Tomás-Vidal, A. (2016). Potential use of high levels of vegetal proteins in diets for market-sized gilthead sea bream (Sparus aurata). Archives of Animal Nutrition, 70(2), 155-172. doi:10.1080/1745039x.2016.1141743Baeza-Ariño, R., Martínez-Llorens, S., Nogales-Mérida, S., Jover-Cerda, M., & Tomás-Vidal, A. (2014). Study of liver and gut alterations in sea bream,Sparus aurataL., fed a mixture of vegetable protein concentrates. Aquaculture Research, 47(2), 460-471. doi:10.1111/are.12507Sitjà-Bobadilla, A., Peña-Llopis, S., Gómez-Requeni, P., Médale, F., Kaushik, S., & Pérez-Sánchez, J. (2005). Effect of fish meal replacement by plant protein sources on non-specific defence mechanisms and oxidative stress in gilthead sea bream (Sparus aurata). Aquaculture, 249(1-4), 387-400. doi:10.1016/j.aquaculture.2005.03.031Estruch, G., Collado, M. C., Monge-Ortiz, R., Tomás-Vidal, A., Jover-Cerdá, M., Peñaranda, D. S., … Martínez-Llorens, S. (2018). Long-term feeding with high plant protein based diets in gilthead seabream (Sparus aurata, L.) leads to changes in the inflammatory and immune related gene expression at intestinal level. BMC Veterinary Research, 14(1). doi:10.1186/s12917-018-1626-6DE FRANCESCO, M., PARISI, G., PÉREZ-SÁNCHEZ, J., GÓMEZ-RéQUENI, P., MÉDALE, F., KAUSHIK, S. J., … POLI, B. M. (2007). Effect of high-level fish meal replacement by plant proteins in gilthead sea bream (Sparus aurata) on growth and body/fillet quality traits. Aquaculture Nutrition, 13(5), 361-372. doi:10.1111/j.1365-2095.2007.00485.xHernández, M. D., López, M. B., Álvarez, A., Ferrandini, E., García García, B., & Garrido, M. D. (2009). Sensory, physical, chemical and microbiological changes in aquacultured meagre (Argyrosomus regius) fillets during ice storage. Food Chemistry, 114(1), 237-245. doi:10.1016/j.foodchem.2008.09.045Matos, E., Silva, T. S., Colen, R., Dinis, M. T., & Dias, J. (2014). Plant protein and vegetable oil-based diets modulate gilthead seabream (Sparus aurata) muscle biochemical status and proteolytic enzymes at an early postmortem stage. Aquaculture Nutrition, 20(2), 153-162. doi:10.1111/anu.12061Goulas, A. E., & Kontominas, M. G. (2005). Effect of salting and smoking-method on the keeping quality of chub mackerel (Scomber japonicus): biochemical and sensory attributes. Food Chemistry, 93(3), 511-520. doi:10.1016/j.foodchem.2004.09.040Olafsdottir, G., Nesvadba, P., Di Natale, C., Careche, M., Oehlenschläger, J., Tryggvadóttir, S. V., … Jørgensen, B. M. (2004). Multisensor for fish quality determination. Trends in Food Science & Technology, 15(2), 86-93. doi:10.1016/j.tifs.2003.08.006Zaragozá, P., Fuentes, A., Fernández-Segovia, I., Vivancos, J.-L., Rizo, A., Ros-Lis, J. V., … Martínez-Máñez, R. (2013). Evaluation of sea bream (Sparus aurata) shelf life using an optoelectronic nose. Food Chemistry, 138(2-3), 1374-1380. doi:10.1016/j.foodchem.2012.10.114Gribbestad, I. S., Aursand, M., & Martinez, I. (2005). High-resolution 1H magnetic resonance spectroscopy of whole fish, fillets and extracts of farmed Atlantic salmon (Salmo salar) for quality assessment and compositional analyses. Aquaculture, 250(1-2), 445-457. doi:10.1016/j.aquaculture.2005.02.031Folkestad, A., Wold, J. P., Rørvik, K.-A., Tschudi, J., Haugholt, K. H., Kolstad, K., & Mørkøre, T. (2008). Rapid and non-invasive measurements of fat and pigment concentrations in live and slaughtered Atlantic salmon (Salmo salar L.). Aquaculture, 280(1-4), 129-135. doi:10.1016/j.aquaculture.2008.04.037Olsen, S. H., Sørensen, N. K., Larsen, R., Elvevoll, E. O., & Nilsen, H. (2008). Impact of pre-slaughter stress on residual blood in fillet portions of farmed Atlantic cod (Gadus morhua) — Measured chemically and by Visible and Near-infrared spectroscopy. Aquaculture, 284(1-4), 90-97. doi:10.1016/j.aquaculture.2008.07.042Chen, Q., Zhang, C., Zhao, J., & Ouyang, Q. (2013). Recent advances in emerging imaging techniques for non-destructive detection of food quality and safety. TrAC Trends in Analytical Chemistry, 52, 261-274. doi:10.1016/j.trac.2013.09.007Salinas, Y., Ros-Lis, J. V., Vivancos, J.-L., Martínez-Máñez, R., Marcos, M. D., Aucejo, S., … Garcia, E. (2014). A novel colorimetric sensor array for monitoring fresh pork sausages spoilage. Food Control, 35(1), 166-176. doi:10.1016/j.foodcont.2013.06.043Salinas, Y., Ros-Lis, J. V., Vivancos, J.-L., Martínez-Máñez, R., Marcos, M. D., Aucejo, S., … Lorente, I. (2012). Monitoring of chicken meat freshness by means of a colorimetric sensor array. The Analyst, 137(16), 3635. doi:10.1039/c2an35211gPeres, H., & Oliva-Teles, A. (2009). The optimum dietary essential amino acid profile for gilthead seabream (Sparus aurata) juveniles. Aquaculture, 296(1-2), 81-86. doi:10.1016/j.aquaculture.2009.04.046Martínez-Llorens, S., Vidal, A. T., Moñino, A. V., Torres, M. P., & Cerdá, M. J. (2007). Effects of dietary soybean oil concentration on growth, nutrient utilization and muscle fatty acid composition of gilthead sea bream (Sparus aurata L.). Aquaculture Research, 38(1), 76-81. doi:10.1111/j.1365-2109.2006.01636.xMoragues, M. E., Esteban, J., Ros-Lis, J. V., Martínez-Máñez, R., Marcos, M. D., Martínez, M., … Sancenón, F. (2011). Sensitive and Selective Chromogenic Sensing of Carbon Monoxide via Reversible Axial CO Coordination in Binuclear Rhodium Complexes. Journal of the American Chemical Society, 133(39), 15762-15772. doi:10.1021/ja206251rZaragozá, P., Fernández-Segovia, I., Fuentes, A., Vivancos, J.-L., Ros-Lis, J. V., Barat, J. M., & Martínez-Máñez, R. (2014). Monitorization of Atlantic salmon (Salmo salar) spoilage using an optoelectronic nose. 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J., Diez, A., Corraze, G., Arzel, J., Alvarez, M., Dias, J., … Bautista, J. M. (2001). Dietary protein source affects the susceptibility to lipid peroxidation of rainbow trout (Oncorhynchus mykiss) and sea bass (Dicentrarchus labrax) muscle. Animal Science, 73(3), 443-449. doi:10.1017/s1357729800058410Hosseini, S. V., Abedian-Kenari, A., Rezaei, M., Nazari, R. M., Feás, X., & Rabbani, M. (2010). Influence of the in vivo addition of alpha-tocopheryl acetate with three lipid sources on the lipid oxidation and fatty acid composition of Beluga sturgeon, Huso huso, during frozen storage. Food Chemistry, 118(2), 341-348. doi:10.1016/j.foodchem.2009.04.131Ng, W. (2004). Replacement of dietary fish oil with palm fatty acid distillate elevates tocopherol and tocotrienol concentrations and increases oxidative stability in the muscle of African catfish, Clarias gariepinus. Aquaculture, 233(1-4), 423-437. doi:10.1016/j.aquaculture.2003.10.013Regost, C., Jakobsen, J. V., & Rørå, A. M. B. (2004). 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Analysis of the impact of charging of PHEV and EV in Spain

This paper studies the effect of different penetration rates of plug-in hybrid electric vehicles (PHEVs) and electric vehicles (EV) in the Spanish electrical system. A stochastic model for the average trip evaluation and for the arriving and departure times is used to determine the availability of the vehicles for charging. A novel advanced charging algorithm is proposed, which avoids any communication among all agents. Its performance is determined through different charging scenarios

Determinación de la incidencia de bacterias nosocomiales aisladas en hemocultivos de pacientes ingresados en el Hospital Nacional San Juan de Dios de la ciudad de San Miguel, período de junio a septiembre de 2006

La investigación se realizó con los pacientes ingresados en los servicios del Hospital Nacional San Juan de Dios de la ciudad de San Miguel, a los que se les indicó un hemocultivo, con el objetivo general de “Determinar la incidencia de bacterias nosocomiales aisladas en Hemocultivos de pacientes ingresados en el hospital antes mencionado”; para lo cual se procesaron 39 Hemocultivos en el período de junio a septiembre de 2006. La investigación fue de tipo Prospectivo, Transversal, Analítica, de Campo y de Laboratorio; para lo cual se inocularon las muestras de sangre en Caldo Infusión Cerebro Corazón de Buey (BHI) con SPS, para permitir la proliferación de las bacterias y luego se realizó la resiembra del caldo en Agar MacConkey (AMC), Agar Sangre de Carnero (ASC), Agar Chocolate (ACH), para su identificación, lo que proporcionó los datos para la elaboración de cuadros y gráficos observándose los siguientes resultados: De los 39 Hemocultivos procesados se obtuvieron 30 negativos y 9 positivos; de estos 9 positivos el Staphylococcus spp fue el aislado con mayor frecuencia (4 casos); de los 9 pacientes con Septicemia, 5 habían mantenido colocado un catéter por más de 5 días y se observó que la mayoría de Hemocultivos Positivos provenían de la Unidad de Cuidados Intensivos (UCI) con 4 casos positivos. De acuerdo con los resultados y las conclusiones de la investigación se plantean algunas recomendaciones orientadas principalmente a dar seguimiento y brindar apoyo a este tipo de investigacione

Enzymatic acylation of di- and trisaccharides with fatty acids: choosing the appropriate enzyme, support and solvent

Enzymatic synthesis of fatty acid esters of di- and trisaccharides is limited by the fact that most biological catalysts are inactivated by the polar solvents (e.g. dimethylsulfoxide, dimethylformamide) where these carbohydrates are soluble. This article reviews the methodologies developed to overcome this limitation, namely those involving control over the reaction medium, the enzyme and the support. We have proposed the use of mixtures of miscible solvents (e.g. dimethylsulfoxide and 2-methyl-2-butanol) as a general strategy to acylate enzymatically hydrophilic substrates. We observed that decreasing the hydrophobicity of the medium (i.e. lowering the percentage of DMSO) the molar ratio sucrose diesters vs. sucrose monoesters can be substantially enhanced. The different regioselectivity exhibited by several lipases and proteases makes feasible to synthesize different positional isomers, whose properties may vary considerably. In particular, the lipase from Thermomyces lanuginosus displays a notable selectivity for only one hydroxyl group in the acylation of sucrose, maltose, leucrose and maltotriose, compared with lipase from Candida antarctica. We have examined three immobilisation methods (adsorption on polypropylene, covalent coupling to Eupergit C, and silica-granulation) for sucrose acylation catalyzed by T. lanuginosus lipase. The morphology of the support affected significantly the reaction rate and/or the selectivity of the processWe are grateful to Loreto Bajón (Instituto de Catálisis) for technical help with electron microscopy. We are indebted to Jordi Sucrana (Degusa Texturant Systems, Barcelona, Spain) and Naoya Otomo (Mitsubishi Kagaku Foods Co., Tokyo, Japan) for technical help. We thank Comunidad de Madrid and Ministerio de Ciencia y Tecnología for research fellowships. This work was supported by the E.U. (Project BIO4-CT98-0363), the Spanish CICYT (Projects BIO98-0793 and BIO1999-1710-CE), and Comunidad de Madrid (Project 07G/0042/2000)Peer reviewe