60 research outputs found

    Computational Screening of Structure-Directing Agents for the Synthesis of Pure Silica ITE Zeolite

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    This document is the Accepted Manuscript version of a Published Work that appeared in final form in The Journal of Physical Chemistry Letters, copyright © American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see https://doi.org/10.1021/acs.jpclett.0c01734.[EN] "Shape" was the first criterion claimed to explain the specificity between organic structure-directing agents (OSDAs) and zeolite micropores. With the advent of computational chemistry methods applied to study the effectiveness of SDA-zeolite combinations, "energy" (mainly van der Waals) became the most commonly invoked concept to explain the zeolite phase selectivity. The lower the energy, the better the SDA_ In this study, we rescue the concept of shape, and we combine it with the concept of energy within the frame of a SDA screening approach to identify new SDAs for the synthesis of cage-based ITE zeolite. Once we identify an appropriate shape fingerprint, filtering through the SDA database can be done quickly and accurately. With the shape selection, an automated Monte Carlo software allows us to assess the suitability using the force-field-calculated zeo-SDA energy. The computational approach can be promptly applied to other cage-based zeolites.We thank MICINN of Spain for funding through projects RTI2018-101784-B-I00, RTI2018-101033-B-I00, and SEV-2016-0683. S.L. thanks MICINN for the predoctoral grant BES-2017-081245 corresponding to project SEV-2016-068317-2. Prof. A. Corma is acknowledged for collaboration from the SEV-2016-0683 project. We thank ASIC-UPV for the use of their computational facilities.León-Rubio, S.; Sastre Navarro, GI. (2020). Computational Screening of Structure-Directing Agents for the Synthesis of Pure Silica ITE Zeolite. The Journal of Physical Chemistry Letters. 11(15):6164-6167. https://doi.org/10.1021/acs.jpclett.0c01734S616461671115Davis, M. E. (2013). Zeolites from a Materials Chemistry Perspective. Chemistry of Materials, 26(1), 239-245. doi:10.1021/cm401914uLi, J., Corma, A., & Yu, J. (2015). Synthesis of new zeolite structures. Chemical Society Reviews, 44(20), 7112-7127. doi:10.1039/c5cs00023hČejka, J., Millini, R., Opanasenko, M., Serrano, D. P., & Roth, W. J. (2020). Advances and challenges in zeolite synthesis and catalysis. Catalysis Today, 345, 2-13. doi:10.1016/j.cattod.2019.10.021Rimer, J. D. (2018). Rational design of zeolite catalysts. Nature Catalysis, 1(7), 488-489. doi:10.1038/s41929-018-0114-5Barrer, R. M. (1960). Stabilization of lattices by sorbed and included molecules. Journal of Physics and Chemistry of Solids, 16(1-2), 84-89. doi:10.1016/0022-3697(60)90076-7Zones, S. I. (1989). Synthesis of pentasil zeolites from sodium silicate solutions in the presence of quaternary imidazole compounds. Zeolites, 9(6), 458-467. doi:10.1016/0144-2449(89)90039-0Davis, M. E. (1993). New vistas in zeolite and molecular sieve catalysis. Accounts of Chemical Research, 26(3), 111-115. doi:10.1021/ar00027a006Gies, H., & Marker, B. (1992). The structure-controlling role of organic templates for the synthesis of porosils in the systems SiO2/template/H2O. Zeolites, 12(1), 42-49. doi:10.1016/0144-2449(92)90008-dBoyett, R. E., Stevens, A. P., Ford, M. G., & Cox, P. A. (1996). A quantitative shape analysis of organic templates employed in zeolite synthesis. Zeolites, 17(5-6), 508-512. doi:10.1016/s0144-2449(96)00073-5Bell, R. G., Lewis, D. W., Voigt, P., Freeman, C. M., Thomas, J. M., & Catlow, C. R. A. (1994). Computer Modelling of Sorbates and Templates in Microporous Materials. Zeolites and Related Microporous Materials: State of the Art 1994 - Proceedings of the 10th International Zeolite Conference, Garmisch-Partenkirchen, Germany, 17-22 July 1994, 2075-2082. doi:10.1016/s0167-2991(08)63768-4Cox, P. A., Casci, J. L., & Stevens, A. P. (1997). Molecular modelling of templated zeolite synthesis. Faraday Discussions, 106, 473-487. doi:10.1039/a701487bWagner, P., Nakagawa, Y., Lee, G. S., Davis, M. E., Elomari, S., Medrud, R. C., & Zones, S. I. (2000). Guest/Host Relationships in the Synthesis of the Novel Cage-Based Zeolites SSZ-35, SSZ-36, and SSZ-39. Journal of the American Chemical Society, 122(2), 263-273. doi:10.1021/ja990722uShi, C., Li, L., Yang, L., & Li, Y. (2020). Molecular simulations of host-guest interactions between zeolite framework STW and its organic structure-directing agents. Chinese Chemical Letters, 31(7), 1951-1955. doi:10.1016/j.cclet.2020.01.016Burton, A. W., Lee, G. S., & Zones, S. I. (2006). Phase selectivity in the syntheses of cage-based zeolite structures: An investigation of thermodynamic interactions between zeolite hosts and structure directing agents by molecular modeling. Microporous and Mesoporous Materials, 90(1-3), 129-144. doi:10.1016/j.micromeso.2005.11.022Gálvez-Llompart, M., Cantín, A., Rey, F., & Sastre, G. (2018). Computational screening of structure directing agents for the synthesis of zeolites. A simplified model. Zeitschrift für Kristallographie - Crystalline Materials, 234(7-8), 451-460. doi:10.1515/zkri-2018-2132Gálvez-Llompart, M., Gálvez, J., Rey, F., & Sastre, G. (2020). Identification of New Templates for the Synthesis of BEA, BEC, and ISV Zeolites Using Molecular Topology and Monte Carlo Techniques. Journal of Chemical Information and Modeling, 60(6), 2819-2829. doi:10.1021/acs.jcim.0c00231Schmidt, J. E., Deem, M. W., & Davis, M. E. (2014). Synthesis of a Specified, Silica Molecular Sieve by Using Computationally Predicted Organic Structure-Directing Agents. Angewandte Chemie International Edition, 53(32), 8372-8374. doi:10.1002/anie.201404076Daeyaert, F., & Deem, M. W. (2019). Design of organic structure directing agents for polymorph A zeolite beta. Journal of Materials Chemistry A, 7(16), 9854-9866. doi:10.1039/c8ta11913aDaeyaert, F., Ye, F., & Deem, M. W. (2019). Machine-learning approach to the design of OSDAs for zeolite beta. Proceedings of the National Academy of Sciences, 116(9), 3413-3418. doi:10.1073/pnas.1818763116Camblor, M. A., Corma, A., Lightfoot, P., Villaescusa, L. A., & Wright, P. A. (1997). Synthesis and Structure of ITQ-3, the First Pure Silica Polymorph with a Two-Dimensional System of Straight Eight-Ring Channels. Angewandte Chemie International Edition in English, 36(23), 2659-2661. doi:10.1002/anie.199726591Olson, D. H., Camblor, M. A., Villaescusa, L. A., & Kuehl, G. H. (2004). Light hydrocarbon sorption properties of pure silica Si-CHA and ITQ-3 and high silica ZSM-58. Microporous and Mesoporous Materials, 67(1), 27-33. doi:10.1016/j.micromeso.2003.09.025SciFinder; CAS: Columbus, OH, 2020. https://www.cas.org/products/scifinder. (Accessed July 15th, 2020)Foster, M. D., Rivin, I., Treacy, M. M. J., & Delgado Friedrichs, O. (2006). A geometric solution to the largest-free-sphere problem in zeolite frameworks. Microporous and Mesoporous Materials, 90(1-3), 32-38. doi:10.1016/j.micromeso.2005.08.02

    Diseño de propuesta de mejoramiento para el proceso de recolección y transporte de títulos valores y correspondencia del Banco Davivienda en la ciudad de Medellín a cargo de una empresa outsourcing

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    El trabajo de grado realiza un análisis logístico del proceso de recolección y transporte de títulos valores y correspondencia del Banco Davivienda en la ciudad de Medellín, con el fin de evaluar e identificar falencias y posibles mejoras del proceso, adicionalmente a partir de una heurística y enfocado en el problema CVRPTWMD(Capacited vehicule routing problem with time windows and multiple delivery men), se realiza una nueva ruta para los motorizados cumpliendo con las restricciones impuestas por el Banco Davivienda, evaluando la opción de que el proceso deje de ser tercerizado y sea realizado por el Banco, con su respectivo análisis financiero, que determinó la viabilidad de la propuesta.This degree work makes a logistical analysis of the pick up and transports of securities assets and documents of Davivienda in the city of Medellín, in order to evaluate and identify possible improvements and shortcuts of the process. Also with the design of a heuristic based on the CVRPTWMD (Capacited vehicule routing problem with time windows and multiple delivery men), designed different routes for each vehicle satisfying all the restrictions imposed by the bank in order to avoid doing the entire process by an outsourcing company.Ingeniero (a) IndustrialPregrad

    Vision-based techniques for automatic marine plankton classification

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    Plankton are an important component of life on Earth. Since the 19th century, scientists have attempted to quantify species distributions using many techniques, such as direct counting, sizing, and classification with microscopes. Since then, extraordinary work has been performed regarding the development of plankton imaging systems, producing a massive backlog of images that await classification. Automatic image processing and classification approaches are opening new avenues for avoiding time-consuming manual procedures. While some algorithms have been adapted from many other applications for use with plankton, other exciting techniques have been developed exclusively for this issue. Achieving higher accuracy than that of human taxonomists is not yet possible, but an expeditious analysis is essential for discovering the world beyond plankton. Recent studies have shown the imminent development of real-time, in situ plankton image classification systems, which have only been slowed down by the complex implementations of algorithms on low-power processing hardware. This article compiles the techniques that have been proposed for classifying marine plankton, focusing on automatic methods that utilize image processing, from the beginnings of this field to the present day.Funding for open access charge: Universidad de Málaga / CBUA. Open Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature. The authors wish to thank Alonso Hernández-Guerra for his frm support in the development of oceanographic technology. Special thanks to Laia Armengol for her help in the domain of plankton. This study has been funded by Feder of the UE through the RES-COAST Mac-Interreg pro ject (MAC2/3.5b/314). We also acknowledge the European Union projects SUMMER (Grant Agreement 817806) and TRIATLAS (Grant Agreement 817578) from the Horizon 2020 Research and Innovation Programme and the Ministry of Science from the Spanish Government through the Project DESAFÍO (PID2020-118118RB-I00)

    Active flux seasonality of the small dominant migratory crustaceans and mesopelagic fishes in the Gulf of California during June and October

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    The biological carbon pump is the process that transports carbon vertically out of the mixed layer in the ocean. Besides the sinking flux of organic particles, active flux due to the daily vertical migration of zooplankton and micronekton promotes a significant carbon transport not fully accounted for or understood in the world’s oceans. The diversity and abundance of epipelagic and mesopelagic species in the Gulf of California has been extensively studied, but the role of micronekton in carbon export has not yet been investigated. We studied the carbon flux promoted by juvenile and adult mesopelagic fishes and crustaceans (Decapoda and Euphausiidae) during the transition from the cold to warm period (June) and the onset of the warm season (October) in 2018. We provide the first estimation of migrant biomass and respiratory flux of the most abundant migratory species of mesopelagic fishes, decapods and euphausiids in the Gulf of California. The micronekton species collected accounted for a large biomass of mesopelagic fishes and pelagic crustaceans. The average migrant biomass estimates were 151.5 ± 101.2 mg C·m−2 during June and 90.9 ± 75.3 mg C·m−2 during October. The enzymatic activity of the electron transfer system (ETS) was measured as an estimate of their respiratory rates. Average specific ETS activity was significantly different between fishes and decapods, and between fishes and euphausiids (p < 0.05). The respiratory flux of fishes was predominant in the Gulf of California, followed by pelagic decapods and euphausiids. Seasonal changes in respiratory flux were observed for fishes (June: 6.1 ± 1.5 mg C·m−2·d−1; October: 3.2 ± 1.8 mg C·m−2·d−1) and decapods (June: 0.4 mg C·m−2·d−1; October: 0.7 ± 0.05 mg C·m−2·d−1). Respiratory flux estimation by crustaceans (decapods and euphausiids) and fishes together was 6.86 mg C·m−2·d−1 during June, and 4.21 mg C·m−2·d−1 during October 2018, suggesting a functional role of this large micronektonic fauna in the biological carbon export in this region.3,26

    Actualización sobre técnicas quirúrgicas empleadas en el tratamiento del carcinoma epidermoide de labio

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    Introduction:?the knowledge of the most advanced surgical techniques used for the treatment of squamous cell carcinoma of the lip is of great importance today, where lip cancer has a high incidence.Objective:?characterizing the surgical techniques used in the treatment of squamous cell carcinoma of the lip.Methods:?an updated bibliographic review on the topic was carried out between January and February 2023. For this purpose, textbooks and resources available on the Infomed network were used, through the Medline, Academic Search Premier, MedicLatina databases; in addition to Cudmed, Lilacs and Scopus. Of a total of 156 articles related to the topic, 25 were selected according to date and relevance.Development:?lip reconstruction techniques depend on the magnitude and location of the defect. Losange excision is used in localized superficial keratotic lesions, and decortication is used in diffuse lesions. When it takes less than a third of the lip, the V technique is used. When more than a third and less than two thirds centrally is present, it is generally used the Abb?-Estlander technique. On the sides, the Estlander or Gillies Fan Flap technique is used and in injuries that take more than two-thirds of the lip, the Karapandzic technique is mostly applied.Conclusions: the surgical techniques used in the treatment of squamous cell carcinoma of the lip try to adapt a reconstruction that is as aesthetic and functional as possible to each defect.Introducción: el conocimiento de las más avanzadas técnicas quirúrgicas que se emplean para el tratamiento del carcinoma epidermoide de labio es de gran importancia en la actualidad, donde el cáncer labial tiene alta incidencia. Objetivo: caracterizar las técnicas quirúrgicas empleadas en el tratamiento del carcinoma epidermoide de labio. Métodos: se realizó una revisión bibliográfica actualizada sobre el tema entre enero y febrero de 2023. Para ello se emplearon libros de texto y los recursos disponibles en la red Infomed, a través de las bases de datos Medline, Academic Search Premier, MedicLatina; además de Cudmed, Lilacs y Scopus. De un total de 156 artículos relacionados con la temática fueron seleccionados 25 de acuerdo a la fecha y relevancia. Desarrollo: las técnicas de reconstrucción labial dependen de la magnitud y localización del defecto. En lesiones queratósicas superficiales localizadas se utiliza la exéresis en losange y en las difusas la decorticación. Cuando toman menos de un tercio del labio se utiliza la técnica en V. Cuando centralmente toman más de un tercio y menos de dos tercios, se emplea generalmente la de Abbé-Estlander. En las laterales, la técnica de Estlander o Fan Flap de Gillies y en lesiones que toman más de dos tercios del labio se utiliza mayormente la de Karapandzic. Conclusiones: las técnicas quirúrgicas empleadas en el tratamiento del carcinoma epidermoide de labio tratan de adecuar a cada defecto una reconstrucción lo más estética y funcional posible

    Discourse Analysis and Terminology in Languages for Specific Purposes

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    Aquest importantíssim recull conté estudis i reflexions sobre temes rellevants en la recerca sobre LSP: anglès mèdic, el llenguatge de la publicitat i periodístic, telecomunicacions i terminologia informàtica, llenguatge comercial i jurídic... Malgrat que gran part dels treballs aplegats es refereixen a l'anglès, també hi ha que tracten l'alemany, francès i altres llengües. Conté textos en anglès, francés, portuguès i castellà

    The Historiography of Missionary Linguistics

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    Effectiveness of an intervention for improving drug prescription in primary care patients with multimorbidity and polypharmacy:Study protocol of a cluster randomized clinical trial (Multi-PAP project)

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    This study was funded by the Fondo de Investigaciones Sanitarias ISCIII (Grant Numbers PI15/00276, PI15/00572, PI15/00996), REDISSEC (Project Numbers RD12/0001/0012, RD16/0001/0005), and the European Regional Development Fund ("A way to build Europe").Background: Multimorbidity is associated with negative effects both on people's health and on healthcare systems. A key problem linked to multimorbidity is polypharmacy, which in turn is associated with increased risk of partly preventable adverse effects, including mortality. The Ariadne principles describe a model of care based on a thorough assessment of diseases, treatments (and potential interactions), clinical status, context and preferences of patients with multimorbidity, with the aim of prioritizing and sharing realistic treatment goals that guide an individualized management. The aim of this study is to evaluate the effectiveness of a complex intervention that implements the Ariadne principles in a population of young-old patients with multimorbidity and polypharmacy. The intervention seeks to improve the appropriateness of prescribing in primary care (PC), as measured by the medication appropriateness index (MAI) score at 6 and 12months, as compared with usual care. Methods/Design: Design:pragmatic cluster randomized clinical trial. Unit of randomization: family physician (FP). Unit of analysis: patient. Scope: PC health centres in three autonomous communities: Aragon, Madrid, and Andalusia (Spain). Population: patients aged 65-74years with multimorbidity (≥3 chronic diseases) and polypharmacy (≥5 drugs prescribed in ≥3months). Sample size: n=400 (200 per study arm). Intervention: complex intervention based on the implementation of the Ariadne principles with two components: (1) FP training and (2) FP-patient interview. Outcomes: MAI score, health services use, quality of life (Euroqol 5D-5L), pharmacotherapy and adherence to treatment (Morisky-Green, Haynes-Sackett), and clinical and socio-demographic variables. Statistical analysis: primary outcome is the difference in MAI score between T0 and T1 and corresponding 95% confidence interval. Adjustment for confounding factors will be performed by multilevel analysis. All analyses will be carried out in accordance with the intention-to-treat principle. Discussion: It is essential to provide evidence concerning interventions on PC patients with polypharmacy and multimorbidity, conducted in the context of routine clinical practice, and involving young-old patients with significant potential for preventing negative health outcomes. Trial registration: Clinicaltrials.gov, NCT02866799Publisher PDFPeer reviewe
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