8 research outputs found
Offshore aquaculture as climate change adaptation in coastal areas: sea surface temperature trends in the Western Mediterranean Sea
The warming of the Mediterranean Sea surface is currently estimated to have been 0.4°C per decade for the period 1985-2006, and the increase in water temperature may have negatively affected marine aquaculture, e.g. by decreasing productivity. Development of aquaculture without adequate planning can lead to unsustainable economic feasibility due to future climate stressors. In this sense, offshore mariculture could be an alternative for mitigating the effect of coastal warming. The purpose of this study was to evaluate the suitability of the coastline in terms of global warming and sea surface temperature trends in locations where fish aquaculture is currently being developed, as well as the spatial changes of thermal anomalies up to 30 km from the coast, during the last 31 yr in the western Mediterranean (Spanish coast). This study was conducted using EU Copernicus Marine Service Information, covering the period 1981-2018, with a spatial resolution of 4 × 4 km. The results show that, over the last decade, the Mediterranean coastal environment off the Iberian Peninsula has experienced an increase in temperature of around 1ºC due to global change, with a clear latitudinal pattern modified by mesoscale oceanographic processes. The development of offshore aquaculture at some latitudes mitigates the extreme aestival effects on surface water temperatures. Strategic plans for aquaculture development should be able to forecast and incorporate future climate projections and local oceanographic conditions, and offshore aquaculture may provide an alternative in some regions, depending on local oceanographic conditions
The Influence of the Support on the Activity of Mn-Fe Catalysts Used for the Selective Catalytic Reduction of NOx with Ammonia
[EN] Mono and bimetallic Mn-Fe catalysts supported on different materials were prepared and their catalytic performance in the NH3-SCR of NOx was investigated. It was shown that Mn and Fe have a synergic effect that enhances the activity at low temperature. Nevertheless, the activity of the bimetallic catalysts depends very much on the support selected. The influence of the support on the catalyst activity has been studied using materials with different textural and acid-base properties. Microporous (BEA-zeolite), mesoporous (SBA15 and MCM41) and bulk (metallic oxides) materials with different acidity have been used as supports for the Mn-Fe catalysts. It has been shown that the activity depends on the acidity of the support and on the surface area. Acid sites are necessary for ammonia adsorption and high surface area produces a better dispersion of the active sites resulting in improved redox properties. The best results have been obtained with the catalysts supported on alumina and on beta zeolite. The first one is the most active at low temperatures but it presents some reversible deactivation in the presence of water. The Mn-Fe catalyst supported on beta zeolite is the most active at temperatures higher than 350 degrees C, without any deactivation in the presence of water and with a 100% selectivity towards nitrogen.This research was funded by the Spanish Ministry of Economy and Competitiveness (MINECO/FEDER), projects RTI2018-101784-B-I00 and RTI2018-101033-B-100 and by Generalitat Valenciana and European Social Fund, the pre doctoral grant ACIF2017.López-Hernández, I.; Mengual Cuquerella, J.; Palomares Gimeno, AE. (2020). The Influence of the Support on the Activity of Mn-Fe Catalysts Used for the Selective Catalytic Reduction of NOx with Ammonia. Catalysts. 10(1):1-12. https://doi.org/10.3390/catal10010063S112101Gao, F., Tang, X., Yi, H., Zhao, S., Li, C., Li, J., … Meng, X. (2017). A Review on Selective Catalytic Reduction of NOx by NH3 over Mn–Based Catalysts at Low Temperatures: Catalysts, Mechanisms, Kinetics and DFT Calculations. Catalysts, 7(7), 199. doi:10.3390/catal7070199Yu, J. J., Cheng, J., Ma, C. Y., Wang, H. L., Li, L. D., Hao, Z. P., & Xu, Z. P. (2009). NOx decomposition, storage and reduction over novel mixed oxide catalysts derived from hydrotalcite-like compounds. Journal of Colloid and Interface Science, 333(2), 423-430. doi:10.1016/j.jcis.2009.02.022Forzatti, P. (2001). Present status and perspectives in de-NOx SCR catalysis. Applied Catalysis A: General, 222(1-2), 221-236. doi:10.1016/s0926-860x(01)00832-8Rutkowska, M., Díaz, U., Palomares, A. E., & Chmielarz, L. (2015). Cu and Fe modified derivatives of 2D MWW-type zeolites (MCM-22, ITQ-2 and MCM-36) as new catalysts for DeNO x process. Applied Catalysis B: Environmental, 168-169, 531-539. doi:10.1016/j.apcatb.2015.01.016PALOMARES, A., PRATO, J., IMBERT, F., & CORMA, A. (2007). Catalysts based on tin and beta zeolite for the reduction of NOx under lean conditions in the presence of water. Applied Catalysis B: Environmental, 75(1-2), 88-94. doi:10.1016/j.apcatb.2007.03.013Palomares, A. E., Franch, C., & Corma, A. (2011). Determining the characteristics of a Co-zeolite to be active for the selective catalytic reduction of NOx with hydrocarbons. Catalysis Today, 176(1), 239-241. doi:10.1016/j.cattod.2010.11.092Palomares, A. E., Prato, J. G., & Corma, A. (2003). Co-Exchanged IM5, a Stable Zeolite for the Selective Catalytic Reduction of NO in the Presence of Water and SO2. Industrial & Engineering Chemistry Research, 42(8), 1538-1542. doi:10.1021/ie020345lWang, R., Wu, X., Zou, C., Li, X., & Du, Y. (2018). NOx Removal by Selective Catalytic Reduction with Ammonia over a Hydrotalcite-Derived NiFe Mixed Oxide. Catalysts, 8(9), 384. doi:10.3390/catal8090384Qi, G., & Yang, R. T. (2003). Low-temperature selective catalytic reduction of NO with NH3 over iron and manganese oxides supported on titania. Applied Catalysis B: Environmental, 44(3), 217-225. doi:10.1016/s0926-3373(03)00100-0Forzatti, P., Nova, I., & Tronconi, E. (2009). Enhanced NH3 Selective Catalytic Reduction for NOx Abatement. Angewandte Chemie International Edition, 48(44), 8366-8368. doi:10.1002/anie.200903857Gillot, S., Tricot, G., Vezin, H., Dacquin, J.-P., Dujardin, C., & Granger, P. (2018). Induced effect of tungsten incorporation on the catalytic properties of CeVO4 systems for the selective reduction of NOx by ammonia. Applied Catalysis B: Environmental, 234, 318-328. doi:10.1016/j.apcatb.2018.04.059Krishnan, A. T., & Boehman, A. L. (1998). Selective catalytic reduction of nitric oxide with ammonia at low temperatures. Applied Catalysis B: Environmental, 18(3-4), 189-198. doi:10.1016/s0926-3373(98)00036-8Li, J., Chang, H., Ma, L., Hao, J., & Yang, R. T. (2011). Low-temperature selective catalytic reduction of NOx with NH3 over metal oxide and zeolite catalysts—A review. Catalysis Today, 175(1), 147-156. doi:10.1016/j.cattod.2011.03.034Boningari, T., & Smirniotis, P. G. (2016). Impact of nitrogen oxides on the environment and human health: Mn-based materials for the NO x abatement. Current Opinion in Chemical Engineering, 13, 133-141. doi:10.1016/j.coche.2016.09.004Putluru, S. S. R., Schill, L., Jensen, A. D., Siret, B., Tabaries, F., & Fehrmann, R. (2015). Mn/TiO2 and Mn–Fe/TiO2 catalysts synthesized by deposition precipitation—promising for selective catalytic reduction of NO with NH3 at low temperatures. Applied Catalysis B: Environmental, 165, 628-635. doi:10.1016/j.apcatb.2014.10.060Chmielarz, L., Kuśtrowski, P., Dziembaj, R., Cool, P., & Vansant, E. F. (2006). Catalytic performance of various mesoporous silicas modified with copper or iron oxides introduced by different ways in the selective reduction of NO by ammonia. Applied Catalysis B: Environmental, 62(3-4), 369-380. doi:10.1016/j.apcatb.2005.09.004Chmielarz, L., Dziembaj, R., Grzybek, T., Klinik, J., Łojewski, T., Olszewska, D., & Papp, H. (2000). Catalysis Letters, 68(1/2), 95-100. doi:10.1023/a:1019094327927Gao, Y., Luan, T., Zhang, S., Jiang, W., Feng, W., & Jiang, H. (2019). Comprehensive Comparison between Nanocatalysts of Mn−Co/TiO2 and Mn−Fe/TiO2 for NO Catalytic Conversion: An Insight from Nanostructure, Performance, Kinetics, and Thermodynamics. Catalysts, 9(2), 175. doi:10.3390/catal9020175Song, C., Zhang, L., Li, Z., Lu, Y., & Li, K. (2019). Co-Exchange of Mn: A Simple Method to Improve Both the Hydrothermal Stability and Activity of Cu–SSZ-13 NH3–SCR Catalysts. Catalysts, 9(5), 455. doi:10.3390/catal9050455Paolucci, C., Di Iorio, J. R., Ribeiro, F. H., Gounder, R., & Schneider, W. F. (2016). Catalysis Science of NOx Selective Catalytic Reduction With Ammonia Over Cu-SSZ-13 and Cu-SAPO-34. Advances in Catalysis, 1-107. doi:10.1016/bs.acat.2016.10.002Wu, Z., Jiang, B., & Liu, Y. (2008). Effect of transition metals addition on the catalyst of manganese/titania for low-temperature selective catalytic reduction of nitric oxide with ammonia. Applied Catalysis B: Environmental, 79(4), 347-355. doi:10.1016/j.apcatb.2007.09.039Putluru, S. S. R., Schill, L., Jensen, A. D., & Fehrmann, R. S. N. (2018). Selective Catalytic Reduction of NOx with NH3 on Cu-, Fe-, and Mn-Zeolites Prepared by Impregnation: Comparison of Activity and Hydrothermal Stability. Journal of Chemistry, 2018, 1-11. doi:10.1155/2018/8614747Thirupathi, B., & Smirniotis, P. G. (2012). Nickel-doped Mn/TiO2 as an efficient catalyst for the low-temperature SCR of NO with NH3: Catalytic evaluation and characterizations. Journal of Catalysis, 288, 74-83. doi:10.1016/j.jcat.2012.01.003Peña, D. A., Uphade, B. S., & Smirniotis, P. G. (2004). TiO2-supported metal oxide catalysts for low-temperature selective catalytic reduction of NO with NH3I. Evaluation and characterization of first row transition metals. Journal of Catalysis, 221(2), 421-431. doi:10.1016/j.jcat.2003.09.003Qi, G., Yang, R. T., & Chang, R. (2004). MnOx-CeO2 mixed oxides prepared by co-precipitation for selective catalytic reduction of NO with NH3 at low temperatures. Applied Catalysis B: Environmental, 51(2), 93-106. doi:10.1016/j.apcatb.2004.01.023Roy, S., Viswanath, B., Hegde, M. S., & Madras, G. (2008). Low-Temperature Selective Catalytic Reduction of NO with NH3 over Ti0.9M0.1O2-δ (M = Cr, Mn, Fe, Co, Cu). The Journal of Physical Chemistry C, 112(15), 6002-6012. doi:10.1021/jp7117086Shi, J., Zhang, Z., Chen, M., Zhang, Z., & Shangguan, W. (2017). Promotion effect of tungsten and iron co-addition on the catalytic performance of MnOx/TiO2 for NH3-SCR of NOx. Fuel, 210, 783-789. doi:10.1016/j.fuel.2017.09.035Husnain, N., Wang, E., Li, K., Anwar, M. T., Mehmood, A., Gul, M., … Mao, J. (2018). Iron oxide-based catalysts for low-temperature selective catalytic reduction of NO
x
with NH3. Reviews in Chemical Engineering, 35(2), 239-264. doi:10.1515/revce-2017-0064Wang, X., Wu, S., Zou, W., Yu, S., Gui, K., & Dong, L. (2016). Fe-Mn/Al 2 O 3 catalysts for low temperature selective catalytic reduction of NO with NH 3. Chinese Journal of Catalysis, 37(8), 1314-1323. doi:10.1016/s1872-2067(15)61115-9Thirupathi, B., & Smirniotis, P. G. (2011). Co-doping a metal (Cr, Fe, Co, Ni, Cu, Zn, Ce, and Zr) on Mn/TiO2 catalyst and its effect on the selective reduction of NO with NH3 at low-temperatures. Applied Catalysis B: Environmental, 110, 195-206. doi:10.1016/j.apcatb.2011.09.001Kim, Y. J., Kwon, H. J., Heo, I., Nam, I.-S., Cho, B. K., Choung, J. W., … Yeo, G. K. (2012). Mn–Fe/ZSM5 as a low-temperature SCR catalyst to remove NOx from diesel engine exhaust. Applied Catalysis B: Environmental, 126, 9-21. doi:10.1016/j.apcatb.2012.06.010Huang, J., Tong, Z., Huang, Y., & Zhang, J. (2008). Selective catalytic reduction of NO with NH3 at low temperatures over iron and manganese oxides supported on mesoporous silica. Applied Catalysis B: Environmental, 78(3-4), 309-314. doi:10.1016/j.apcatb.2007.09.031Li, J., Yang, C., Zhang, Q., Li, Z., & Huang, W. (2015). Effects of Fe addition on the structure and catalytic performance of mesoporous Mn/Al–SBA-15 catalysts for the reduction of NO with ammonia. Catalysis Communications, 62, 24-28. doi:10.1016/j.catcom.2015.01.003Chen, Z., Wang, F., Li, H., Yang, Q., Wang, L., & Li, X. (2011). Low-Temperature Selective Catalytic Reduction of NOx with NH3 over Fe–Mn Mixed-Oxide Catalysts Containing Fe3Mn3O8 Phase. Industrial & Engineering Chemistry Research, 51(1), 202-212. doi:10.1021/ie201894cPalomares, A. E., Prato, J. ., & Corma, A. (2002). A new active zeolite structure for the selective catalytic reduction (SCR) of nitrogen oxides: ITQ7 zeolite. Catalysis Today, 75(1-4), 367-371. doi:10.1016/s0920-5861(02)00066-4Jeong, N. C., Lee, J. S., Tae, E. L., Lee, Y. J., & Yoon, K. B. (2008). Acidity Scale for Metal Oxides and Sanderson’s Electronegativities of Lanthanide Elements. Angewandte Chemie International Edition, 47(52), 10128-10132. doi:10.1002/anie.200803837Sun, M., Lan, B., Yu, L., Ye, F., Song, W., He, J., … Zheng, Y. (2012). Manganese oxides with different crystalline structures: Facile hydrothermal synthesis and catalytic activities. Materials Letters, 86, 18-20. doi:10.1016/j.matlet.2012.07.011Deng, S., Zhuang, K., Xu, B., Ding, Y., Yu, L., & Fan, Y. (2016). Promotional effect of iron oxide on the catalytic properties of Fe–MnOx/TiO2 (anatase) catalysts for the SCR reaction at low temperatures. Catalysis Science & Technology, 6(6), 1772-1778. doi:10.1039/c5cy01217aFang, N., Guo, J., Shu, S., Luo, H., Chu, Y., & Li, J. (2017). Enhancement of low-temperature activity and sulfur resistance of Fe 0.3 Mn 0.5 Zr 0.2 catalyst for NO removal by NH 3 -SCR. Chemical Engineering Journal, 325, 114-123. doi:10.1016/j.cej.2017.05.053Stobbe, E. R., de Boer, B. A., & Geus, J. W. (1999). The reduction and oxidation behaviour of manganese oxides. Catalysis Today, 47(1-4), 161-167. doi:10.1016/s0920-5861(98)00296-xFiorenza, R., Spitaleri, L., Gulino, A., & Scirè, S. (2018). Ru–Pd Bimetallic Catalysts Supported on CeO2-MnOX Oxides as Efficient Systems for H2 Purification through CO Preferential Oxidation. Catalysts, 8(5), 203. doi:10.3390/catal8050203Tu, Y.-B., Luo, J.-Y., Meng, M., Wang, G., & He, J.-J. (2009). Ultrasonic-assisted synthesis of highly active catalyst Au/MnOx–CeO2 used for the preferential oxidation of CO in H2-rich stream. International Journal of Hydrogen Energy, 34(9), 3743-3754. doi:10.1016/j.ijhydene.2009.03.015Corma, A. (1997). From Microporous to Mesoporous Molecular Sieve Materials and Their Use in Catalysis. Chemical Reviews, 97(6), 2373-2420. doi:10.1021/cr960406nGallo, J. M. 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Evaluation of alternative management tools for recreational fishing of Thunnus thynnus in the Aegean Sea: CPUE of fishing contests data and analysis of You tube data
El gran túnido Thunnus thynnus es uno de los objetivos más populares en la pesca recreativa. Debido a este hecho y a su naturaleza migratoria, la correcta gestión de esta especie es un factor clave para garantizar su viabilidad. El impacto de la pesca recreativa no se evalúa suficientemente debido a la falta de datos, lo que dificulta su comprensión. El objetivo de esta tesis es proporcionar herramientas complementarias de estudio utilizando los datos de CPUE obtenidos mediante metodologías alternativas. Los temas elegidos son el concurso de pesca, que es un gran incentivo para la economía turística, y los datos de YouTube. El CPUE se ha estimado utilizando el concurso de pesca de atún en diferentes localidades de la península de Urla entre 2016 y 2022. El efecto de los años se ha estudiado utilizando un modelo GAM, añadiendo también los valores de temperatura superficial del mar (SST) y clorofila a. Los resultados muestran una influencia a lo largo de los años. El promedio total de CPUE fue de 5,56 ± 0,49 Kg*día-1 y los datos anuales más altos de CPUE fueron de 13,98 Kg*día-1 en 2018; se registraron pesos individuales de BFT desde 305 hasta 10,45 Kg. El tipo de captura es relevante ya que el “Catch” es 21 veces más frecuente que el “Catch And Release”. El área sur alberga una mayor concentración de capturas, lo que puede estar relacionado con las jaulas de engorde de atún. El modelo también se ve influenciado por los años, sin embargo, los datos no son lo suficientemente completos como para apreciar los efectos de las variables ambientales. Sin embargo, el potencial de estos datos debe tenerse en cuenta en un futuro cercano como un hito del esfuerzo de pesca recreativa. El análisis de datos de YouTube muestra una tendencia exponencial alta a lo largo de los años, lo que representa un gran potencial de información, como destacaron otros autores. Las principales palabras clave en los videos son "Yazili", que se refiere al atún de aleta amarilla, "pesca" y "jigging": esto muestra que las características lingüísticas de estas dos especies generan un sesgo en los datos. Por eso, esta metodología no es rentable para esta especie y el idioma es un factor determinante, aunque estos estudios representan una perspectiva futura del análisis de datos para la gestión ambiental
Offshore aquaculture as climate change adaptation in coastal areas: sea surface temperature trends in the Western Mediterranean Sea
The warming of the Mediterranean Sea surface is currently estimated to have been 0.4°C per decade for the period 1985-2006, and the increase in water temperature may have negatively affected marine aquaculture, e.g. by decreasing productivity. Development of aquaculture without adequate planning can lead to unsustainable economic feasibility due to future climate stressors. In this sense, offshore mariculture could be an alternative for mitigating the effect of coastal warming. The purpose of this study was to evaluate the suitability of the coastline in terms of global warming and sea surface temperature trends in locations where fish aquaculture is currently being developed, as well as the spatial changes of thermal anomalies up to 30 km from the coast, during the last 31 yr in the western Mediterranean (Spanish coast). This study was conducted using EU Copernicus Marine Service Information, covering the period 1981-2018, with a spatial resolution of 4 × 4 km. The results show that, over the last decade, the Mediterranean coastal environment off the Iberian Peninsula has experienced an increase in temperature of around 1ºC due to global change, with a clear latitudinal pattern modified by mesoscale oceanographic processes. The development of offshore aquaculture at some latitudes mitigates the extreme aestival effects on surface water temperatures. Strategic plans for aquaculture development should be able to forecast and incorporate future climate projections and local oceanographic conditions, and offshore aquaculture may provide an alternative in some regions, depending on local oceanographic conditions
Inercia y cumplimiento terapéutico en pacientes con diabetes mellitus tipo 2 en atención primaria
Jornadas Nacionales de Robótica y Bioingeniería 2023: Libro de actas
Las Jornadas de Robótica y Bioingeniería de 2023 tienen lugar en la Escuela Técnica Superior de Ingeniería Industrial de la Universidad Politécnica de IVIadrid, entre los días 14 y 16 de junio de 2023. En este evento propiciado por el Comité Español de Automática (CEA) tiene lugar la celebración conjunta de las XII Jornadas Nacionales de Robótica y el XIV Simposio CEA de Bioingeniería.
Las Jornadas Nacionales de Robótica es un evento promovido por el Grupo Temático de Robótica (GTRob) de CEA para dar visibilidad y mostrar las actividades desarrolladas en el ámbito de la investigación y transferencia tecnológica en robótica. Asimismo, el propósito de Simposio de Bioingeniería, que cumple ahora su decimocuarta dicción, es el de proporcionar un espacio de encuentro entre investigadores, desabolladores, personal clínico, alumnos, industriales, profesionales en general e incluso usuarios que realicen su actividad en el ámbito de la bioingeniería. Estos eventos se han celebrado de forma conjunta en la anualidad 2023.
Esto ha permitido aunar y congregar un elevado número de participantes tanto de la temática robótica como de bioingeniería (investigadores, profesores, desabolladores y profesionales en general), que ha posibilitado establecer puntos de encuentro, sinergias y colaboraciones entre ambos.
El programa de las jornadas aúna comunicaciones científicas de los últimos resultados de investigación obtenidos, por los grupos a nivel español más representativos dentro de la temática de robótica y bioingeniería, así como mesas redondas y conferencias en las que se debatirán los temas de mayor interés en la actualidad.
En relación con las comunicaciones científicas presentadas al evento, se ha recibido un total de 46 ponencias, lo que sin duda alguna refleja el alto interés de la comunidad científica en las Jornadas de Robótica y Bioingeniería. Estos trabajos serán expuestos y presentados a lo largo de un total de 10 sesiones, distribuidas durante los diferentes días de las Jornadas. Las temáticas de los trabajos cubren los principales retos científicos relacionados con la robótica y la bioingeniería: robótica aérea, submarina, terrestre, percepción del entorno, manipulación, robótica social, robótica médica, teleoperación, procesamiento de señales biológicos, neurorehabilitación etc.
Confiamos, y estamos seguros de ello, que el desarrollo de las jornadas sea completamente productivo no solo para los participantes en las Jornadas que podrán establecer nuevos lazos y relaciones fructíferas entre los diferentes grupos, sino también aquellos investigadores que no hayan podido asistir. Este documento que integra y recoge todas las comunicaciones científicas permitirá un análisis más detallado de cada una de las mismas
Evaluation of a quality improvement intervention to reduce anastomotic leak following right colectomy (EAGLE): pragmatic, batched stepped-wedge, cluster-randomized trial in 64 countries
Background
Anastomotic leak affects 8 per cent of patients after right colectomy with a 10-fold increased risk of postoperative death. The EAGLE study aimed to develop and test whether an international, standardized quality improvement intervention could reduce anastomotic leaks.
Methods
The internationally intended protocol, iteratively co-developed by a multistage Delphi process, comprised an online educational module introducing risk stratification, an intraoperative checklist, and harmonized surgical techniques. Clusters (hospital teams) were randomized to one of three arms with varied sequences of intervention/data collection by a derived stepped-wedge batch design (at least 18 hospital teams per batch). Patients were blinded to the study allocation. Low- and middle-income country enrolment was encouraged. The primary outcome (assessed by intention to treat) was anastomotic leak rate, and subgroup analyses by module completion (at least 80 per cent of surgeons, high engagement; less than 50 per cent, low engagement) were preplanned.
Results
A total 355 hospital teams registered, with 332 from 64 countries (39.2 per cent low and middle income) included in the final analysis. The online modules were completed by half of the surgeons (2143 of 4411). The primary analysis included 3039 of the 3268 patients recruited (206 patients had no anastomosis and 23 were lost to follow-up), with anastomotic leaks arising before and after the intervention in 10.1 and 9.6 per cent respectively (adjusted OR 0.87, 95 per cent c.i. 0.59 to 1.30; P = 0.498). The proportion of surgeons completing the educational modules was an influence: the leak rate decreased from 12.2 per cent (61 of 500) before intervention to 5.1 per cent (24 of 473) after intervention in high-engagement centres (adjusted OR 0.36, 0.20 to 0.64; P < 0.001), but this was not observed in low-engagement hospitals (8.3 per cent (59 of 714) and 13.8 per cent (61 of 443) respectively; adjusted OR 2.09, 1.31 to 3.31).
Conclusion
Completion of globally available digital training by engaged teams can alter anastomotic leak rates. Registration number: NCT04270721 (http://www.clinicaltrials.gov)