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Resultados del proyecto Nuevas Generaciones de Aceros Recubiertos
Get PDFProyecto financiado dentro de la Convocatoria del Programa Asturias de ayudas a Centros Tecnológicos en el Principado de Asturias durante el período 2016-2017 de la Consejería de Empleo, Industria y Turismo, Nº de expediente IDI/2016/00029
Optimized Design of a High Input-Voltage-Ripple-Rejection Converter for LED Lighting
Get PDFThe asymmetrical half-bridge (AHB) converter has been deeply analyzed as second stage in ac-dc light emitting diode (LED) drivers. Galvanic isolation, high reliability and high efficiency are their main advantages while a limited duty cycle range (i.e., 0-0.5) and a poor dynamic behavior are their main disadvantages. As second stage of an LED driver, the most demanding requirement for its control loop is cancelling the low-frequency ripple introduced by the first stage. According to its limited maximum attainable bandwidth, this is normally achieved by implementing a feedforward loop. Nonetheless, the static gain of the standard AHB converter presents a nonlinear relation between the output voltage and the duty cycle. As a consequence, the effectiveness of this feedforward loop is limited. In this paper, the use of the zeta AHB converter as second stage of an LED driver is analyzed and an optimized design is proposed. Regarding its advantages, it presents an extended duty cycle range (theoretically, 0-1.0). Besides, it presents a linear relation between the output voltage and the duty cycle. Therefore, although its dynamic behavior is still limited, it can perfectly cancel the low-frequency ripple introduced by the first stage of the LED driver by means of a straightforward feedforward loop. The optimized design proposed in this paper is focused on minimizing the losses in the magnetic components (transformer and inductor) by wisely choosing the value of the two turns ratios of the transformer
Resultados del proyecto Desarrollo de un demostrador de ventana fotoeléctrica
No full textProyecto financiado dentro de la Convocatoria del Programa Asturias de ayudas a Centros Tecnológicos en el Principado de Asturias durante el periodo 2016-2017 de la Consejería de Empleo, Industria y Turismo, nº de expediente IDI/2016/00029
El cultivo de la faba asturiana frente el cambio climático: adaptación de la fecha de siembra
Get PDFEl cultivo de la ‘Faba Asturiana’ se desarrolla en unas condiciones climáticas
muy específicas. Estamos inmersos en un proceso de cambio climático acelerado
que, seguramente, cambiará estas condiciones y exigirá una adaptación.
En este trabajo se estudia el comportamiento de dos variedades de faba en
condiciones adversas y se evalúa el efecto de la fecha de siembr
Alternativas al uso de aditivos en los derivados cárnicos mediante ingredientes con funcionalidad tecnológica equivalente (CLEAN LABEL IDI/2016/000208)
No full textGeneral Framework for the Efficient Optimization of Reflectarray Antennas for Contoured Beam Space Applications
Get PDFThis paper describes a general framework for the optimization of very large reflectarrays for space applications. It employs the generalized Intersection Approach (IA) as optimizing algorithm, integrating a number of techniques that substantially improve the baseline algorithm by accelerating computations while preserving the accuracy of the electromagnetic analysis. In particular, a learning algorithm based on Support Vector Machines (SVMs) is used to obtain a surrogate model of the reflectarray unit cell accelerating the analysis more than three orders of magnitude. For the optimization, the gradient computation is accelerated by employing the technique of differential contributions on the radiated field, which avoids the use of the Fast Fourier Transform (FFT) in the computation of the far field. Finally, to improve the cross-polarization performance, instead of optimizing the crosspolar pattern, the crosspolar discrimination or crosspolar isolation are optimized, improving both the antenna and algorithm performance. Relevant numerical examples are provided to show the capabilities of the proposed framework for a Direct Broadcast Satellite (DBS) mission, showing how to design a contoured beam reflectarray with a European footprint with two different coverage zones. In addition, a complete study of computing time is carried out to analyse the impact of each technique in the optimization process.This work was supported in part by the European Space Agency (ESA) under contract ESTEC/AO/1-7064/12/NL/MH; by the Ministerio de Ciencia, Innovación y Universidades under project TEC2017-86619-R (ARTEINE); by the Ministerio de Economía, Industria y Competitividad under project TEC2016-75103-C2-1-R (MYRADA); by the Gobierno del Principado de Asturias through Programa "Clarín" de Ayudas Postdoctorales / Marie Curie-Cofund under project ACA17-09
Parto de nalgas. Hospital Universitario Central De Asturias
Get PDFProtocolo del Servicio de Obstetricia y Ginecología el HUCA. Área Sanitaria I
Checklist en Obstetricia (2018-2023). Hospital Universitario Central de Asturias
No full textProtocolo del Servicio de Obstetricia y Ginecología el HUCA. Área Sanitaria I
Convertidor modular trifásico CA/CC para aplicaciones LED basado en la suma de luz por fase
Get PDFEste trabajo ha sido financiado por el Ministerio de Economía a través de del proyecto MINECO-17-DPI2016-75760-R y el Gobierno del Principado de Asturias a través del proyecto SV-PA-17-RIS3-4, la beca “Severo Ochoa” BP14-142 y los fondos FEDER.En este artículo se propone el uso de convertidores trifásicos CA/CC basados en una estructura modular para aplicaciones de iluminación con diodos emisores de luz (Light-Emiting Diodes, LEDs). Se aprovecha la estructura modular para controlar la luz de tres cargas LED independientes con tres convertidores elevadores con Corrección del Factor de Potencia (CFP), uno por fase. La luz emitida será la suma de las tres matrices de LEDs. Se aprovechará la naturaleza de la potencia instantánea demandada a la red trifásica por parte del convertidor CA/CC modular para la eliminación de su condensador electrolítico, asegurando también la ausencia de parpadeos en la luz emitida (ausencia de flicker). Se presentará el análisis estático de la topología propuesta, para finalmente validarla a partir de las pruebas realizadas sobre un prototipo de 300 W
Cancer-associated fibroblasts affect breast cancer cell gene expression, invasion and angiogenesis
Get PDFPurpose It has been reported that stromal cell features may affect the clinical outcome of breast cancer patients. Cancer associated fibroblasts (CAFs) represent one of the most abundant cell types within the breast cancer stroma. Here, we aimed to explore the influence of CAFs on breast cancer gene expression, as well as on invasion and angiogenesis.
Methods qRT-PCR was used to evaluate the expression of several cancer progression related genes (S100A4, TGFβ, FGF2, FGF7, PDGFA, PDGFB, VEGFA, IL6, IL8, uPA, MMP2, MMP9, MMP11 and TIMP1) in the human breast cancer-derived cell lines MCF-7 and MDA-MB-231, before and after co-culture with CAFs. Stromal mononuclear inflammatory cell (MIC) MMP11 expression was used to stratify primary tumors. In addition, we assessed the in vitro effects of CAFs on both MDA-MB-231 breast cancer cell invasion and endothelial cell (HUVEC) tube formation.
Results We found that the expression levels of most of the genes tested were significantly increased in both breast cancer-derived cell lines after co-culture with CAFs from either MMP11+ or MMP11- MIC tumors. IL6 and IL8 showed an increased expression in both cancer-derived cell lines after co-culture with CAFs from MMP11+ MIC tumors. We also found that the invasive and angiogenic capacities of, respectively, MDA-MB-231 and HUVEC cells were increased after co-culture with CAFs, especially those from MMP11+ MIC tumors.
Conclusions Our data indicate that tumor-derived CAFs can induce up-regulation of genes involved in breast cancer progression. Our data additionally indicate that CAFs, especially those derived from MMP11+ MIC tumors, can promote breast cancer cell invasion and angiogenesis