2,725 research outputs found
Role of Eu2+ and Dy3+ Concentration in the Persistent Luminescence of Sr2MgSi2O7 Glass-Ceramics
In this study, glass-ceramics based on Sr2MgSi2O7 phosphor co-doped with Eu/Dy were obtained from the sintering and crystallisation of glass powders. The glasses were melted in a gas furnace to simulate an industrial process, and the dopant concentration was varied to optimise the luminescence persistence times. The doped parent glasses showed red emission under UV light excitation due to the doping of Eu3+ ions, while the corresponding glass-ceramics showed persistent blue emission corresponding to the presence of Eu2+ in the crystalline environment. The dopant concentration had a strong impact on the sintering/crystallisation kinetics affecting the final glass-ceramic microstructure. The microstructures and morphology of the crystals responsible for the blue emission were observed by scanning electron microscopy–cathodoluminescence. The composition of the crystallised phases and the distribution of rare-earth (RE) ions in the crystals and in the residual glassy phase were determined by X-ray diffraction and energy dispersive X-ray analysis. The emission and persistence of phosphorescence were studied by photoluminescence.This research was funded by MICINN under projects PID2020-115419GB-C-21/C-22/AEI/ 10.13039/501100011033 and PID2019-107439GB-I00 and by the project PIE-CSIC 201960E016. And The APC was funded by PID2020-115419GB-C-21/C-22/AEI/ 10.13039/501100011033
Structure and luminescent properties of Sm/Dy-doped Sr2MgSi2O7 glass-ceramics
Sm3+-doped and Sm3+/Dy3+ codoped SiO2–SrO–MgO glasses were prepared by conventional melt quenching and Sr2MgSi2O7 based glass–ceramics from sintering and crystallization of the glass powders. The thermal, structural, and optical properties of the glasses and glass–ceramics were investigated as a function of the dopant concentration. The optical characterization includes the photoluminescence spectra and the lifetimes of the 4G5/2 (Sm3+) and 4F9/2 (Dy3+) excited states. In Sm3+ single-doped samples, the emission intensity increases up to a concentration of 0.3 mol% Sm3+ ions and then decreases due to nonradiative energy transfer processes. The emission spectra in the glass–ceramics show a more resolved structure and higher intensity compared to the glass samples, suggesting a different and crystalline environment for the Sm3+ ions. The non-radiative processes also influence the experimental decays of the glass samples which deviate from a single exponential with lifetimes decreasing as Sm3+ concentration increases. The emission and excitation spectra of the codoped samples do not show significant energy transfer between Sm3+ and Dy3+ ions. Different emitting colors can be obtained in the codoped glasses by changing the excitation wavelength. The studied glass–ceramics could be applied as enamels on ceramic or metallic substrates.Funding from MICINN under projects PID2020-115419GB-C-21/C-22/AEI/ 10.13039/501100011033, PID2019-107439GB-I00 and PIE-CSIC 201960E016 is acknowledged
Depuración de Aguas Residuales en la Industria 4.0
Gómez de Gabriel y otros, 2017, "Depuración de Aguas Residuales en la Industria 4.0" , Jornadas de Automática Gijón, 2017Este artículo presenta un sistema de automatización de una estación depuradora de aguas residuales (EDAR) mediante tecnologías de Industria 4.0. Se ha implementado un sistema Internet of Things (IoT) para la obtención de los datos de los sensores y envío de consignas a los actuadores. El sistema posee un sistema de control local que, junto con el resto de los componentes, se modelan como un sistema ciberfísico (CPS). Se ha implementado sobre una planta experimental, se ha creado una base de datos con la información histórica de los datos de los sensores y se están creando funciones para analizar la información e identificar el modelo de la plantaEste trabajo ha sido parcialmente financiado por
el Proyecto Puente B.2. ”Desarrollo de Técnicas
de Control y Estimación Neurogenéticas para
Operación Optima de Reactores Biológicos de Lodos
Activos en Plantas de Tratamiento de Aguas
Residuales”de la Universidad de Málaga, Campus de Excelencia Internacional Andalucía Tech
3D Determination of Area-at-Risk in Acute Myocardial Infarction
MRI methods for acute myocardial infarctio
Comparison of methods for the analysis of Phase Sensitivity Inversion Recovery Images in the Assessment of Myocardial Infarction
Métodos estadísticos para análisis de MRI PSI
Enzymatic fine-tuning for 2-(6-hydroxynaphthyl) β-d-xylopyranoside synthesis catalyzed by the recombinant β-xylosidase BxTW1 from Talaromyces amestolkiae
This article is distributed under the terms of the Creative Commons Attribution 4.0 International License.-- et al.[Background]: Glycosides are compounds displaying crucial biological roles and plenty of applications. Traditionally, these molecules have been chemically obtained, but its efficient production is limited by the lack of regio- and stereo-selectivity of the chemical synthesis. As an interesting alternative, glycosidases are able to catalyze the formation of glycosides in a process considered green and highly selective. In this study, we report the expression and characterization of a fungal ß-xylosidase in Pichia pastoris. The transglycosylation potential of the enzyme was evaluated and its applicability in the synthesis of a selective anti-proliferative compound demonstrated. [Results]: The ß-xylosidase BxTW1 from the ascomycete fungus Talaromyces amestolkiae was cloned and expressed in Pichia pastoris GS115. The yeast secreted 8 U/mL of ß-xylosidase that was purified by a single step of cation-exchange chromatography. rBxTW1 in its active form is an N-glycosylated dimer of about 200 kDa. The enzyme was biochemically characterized displaying a K m and k cat against p-nitrophenyl-ß-d-xylopyranoside of 0.20 mM and 69.3 s¿1 respectively, and its maximal activity was achieved at pH 3 and 60 °C. The glycan component of rBxTW1 was also analyzed in order to interpret the observed loss of stability and maximum velocity when compared with the native enzyme. A rapid screening of aglycone specificity was performed, revealing a remarkable high number of potential transxylosylation acceptors for rBxTW1. Based on this analysis, the enzyme was successfully tested in the synthesis of 2-(6-hydroxynaphthyl) ß-d-xylopyranoside, a well-known selective anti-proliferative compound, enzymatically obtained for the first time. The application of response surface methodology, following a Box-Behnken design, enhanced this production by eightfold, fitting the reaction conditions into a multiparametric model. The naphthyl derivative was purified and its identity confirmed by NMR. [Conclusions]: A ß-xylosidase from T. amestolkiae was produced in P. pastoris and purified. The final yields were much higher than those attained for the native protein, although some loss of stability and maximum velocity was observed. rBxTW1 displayed remarkable acceptor versatility in transxylosylation, catalyzing the synthesis of a selective antiproliferative compound, 2-(6-hydroxynaphthyl) ß-d-xylopyranoside. These results evidence the interest of rBxTW1 for transxylosylation of relevant products with biotechnological interest.This work was carried out with funding from projects BIO2015-68387-R, RTC-2014-1777-3 and CTQ2015-64597-C2 from MINECO and S2013/MAE2972
from Comunidad de Madrid, as well as from the Natural Sciences and Engineering Research Council of Canada. M. Nieto-Domínguez thanks the MINECO for an FPU fellowship.We acknowledge support by the CSIC Open Access Publication Initiative through its Unit of Information Resources for Research (URICI).Peer Reviewe
Algoritmo Level-set para segmentación hepática en TAC con Restricciones de curvatura local
Actas de: XXIX Congreso Anual de la Sociedad Espñaola de Ingeniería Biomédica (CASEIB 2011). Cáceres, 16-18 Noviembre 2011.La cirugía hepática avanzada requiere de una precisa planificación pre-operatoria en la que tanto la segmentación anatómica como la estimación del volumen hepático remanente tienen una importancia clave a la hora de evitar un fallo hepático postoperatorio. En este contexto, algoritmos basados en level-sets han logrado mejores resultados que otros, especialmente cuando se tratan casos con un parénquima hepático alterado o en hígados previamente resecados. Con el objetivo de mejorar las medidas de volumen hepático funcional, se proponen dos estrategias para completar y realzar algoritmos previos basados en level-sets: una estrategia optimizada multi-resolución con curvatura adaptativa y corrección/refinamiento de detalles, junto con un paso semiautomático adicional en el que se imponen restricciones de curvatura local. Los resultados muestran segmentaciones robustas y precisas, especialmente en estructuras alargadas, detectando lesiones internas y evitando fugas o escapes a estructuras proximales.Este trabajo está parcialmente apoyado por los proyectos de investigación PI09/91058, PI09/91065, ENTEPRASE PS-300000-2009-5, AMIT-CDTI, TEC2010-21619-C04 and PRECISION IPT-300000-2010-3, del Ministerio de Ciencia e Innovación de España, el proyecto ARTEMIS de la Comunidad de Madrid y la ayuda de los fondos FEDER de la Unión Europea.Publicad
Technical feasibility of lined mining tunnels in closed coal mines as underground reservoirs of compressed air energy storage systems
[EN] In this paper, four mining levels in a closed coal mine in the Asturian Central Coal Basin (NW Spain) have been selected as a case study to investigate the technical feasibility of underground compressed air energy storage systems. First, in order to determine the suitable level and type of concrete lining, a numerical model has been established to analyze the geomechanical performance considering air pressures of 6, 10, 20 and 25 MPa and three different embodiments of concrete lining. Then, another numerical model is used to study the coupled thermo-mechanical performance at level 3, considering 100 operation cycles between 6 and 10 MPa air pressure using a circular concrete lining with a 20 mm thick sealing layer. The results obtained indicate that the deformations are lower at levels 1 and 3, where the shales are located at the top of the coal seam. Deformations and tensile stresses are significantly reduced when a circular concrete lining is used. As the thermal analysis shows, temperature fluctuations are restricted to sealing layer and concrete lining and do not reach the rock mass itself. Therefore, negligible deformations are produced by the effect of temperature compared to the effect of air pressure. Maximum tensile stress and total displacements during the operation occur at the top of the mining drift and reach 9.5 MPa and 3.6 mm, respectively. A technical feasibility can be achieved using a circular concrete lining with a suitable reinforcement system.S
Vojta Therapy in Neuromotor Development of Pediatrics Patients with Periventricular Leukomalacia: Case Series
Background and Objectives: Vojta therapy is used by physiotherapists and is based on stimulation through peripheral pressure that leads to the activation of involuntary motor response patterns, thus triggering patterns of reflex locomotion, hence also called reflex locomotion therapy. Objective: To analyze the changes produced by Vojta therapy in the evolution of infant motor development in patients with maturational delay due to periventricular leukomalacia. Materials and methods: One session of Vojta Therapy per week for eleven months, patients’ neuromotor development was evaluated through the Denver II Test and the Baleys Scale. Results: A clinically significant increase in the development of the patients is observed. Conclusions: Neuromotor development seems to generate an adequate progression in the motor area
Thermodynamic Analysis of Compressed Air Energy Storage (CAES) Reservoirs in Abandoned Mines Using Different Sealing Layers
[EN] Million cubic meters from abandoned mines worldwide could be used as subsurface reservoirs for large scale energy storage systems, such as adiabatic compressed air energy storage (A-CAES). In this paper, analytical and three-dimensional CFD numerical models have been conducted to analyze the thermodynamic performance of the A-CAES reservoirs in abandoned mines during air charging and discharging processes. Unlike other research works, in which the heat transfer coefficient is considered constant during the operation time, in the present investigation a correlation based on both unsteady Reynolds and Rayleigh numbers is employed for the heat transfer coefficient in this type of application. A tunnel with a 35 cm thick concrete lining, 200 m3 of useful volume and typical operating pressures from 5 to 8 MPa were considered. Fiber-reinforced plastic (FRP) and steel were employed as sealing layers in the simulations around the fluid. Finally, the model also considers a 2.5 m thick sandstone rock mass around the concrete lining. The results obtained show significant heat flux between the pressurized air and the sealing layer and between the sealing layer and concrete lining. However, no temperature fluctuation was observed in the rock mass. The air temperature fluctuations are reduced when steel sealing layer is employed. The thermal energy balance through the sealing layer for 30 cycles, considering air mass flow rates of 0.22 kg s−1 (charge) and −0.45 kg s−1 (discharge), reached 1056 and 907 kWh for FRP and steel, respectively. In general, good agreements between analytical and numerical simulations were obtained.S
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