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The aim of this project had been the infusion specimens manufacturing to support design, analysis and qualification for the “Outcome Lower Skin” pyramid structural tests inside the Clean Sky 2 programm. It is the reinforcement lower skin structural tests pyramid for the C295 military aircraft from Airbus Defence & Space. Along the project UD dry fiber manufacturing process had been developed until to obtain an automatic, robust and efficiency process in order to be able to manufacture a lower skin with stringers and spars integrated and that will be able to compete with the typical prepreg process with regard to fabricability, ratio, performance and cost. The manufacturing process includes the dry fiber pre-forms automatic lay-up by AFP (Automated Fiber Placement), a hot-forming process for the stringers and finally a process infusion by VAP (Vacuum Assisted Process). To achive this goal, the AFP has been set up to optimize the laying parameters for the processing of the material to be used (½” Hexcel Hi-Tape fiber) and RTM6 resin. On the other hand, several tests of hot forming had been carried out modifying process variables, and several infusion bags configurations had been used to stringers and skin integration by infusion (VAP) until to find the key process parameters to obtain valid parts for the structural test pyramid.

BACKGROUND AND PURPOSE: The treatment of symptomatic carotid near-occlusion is controversial. Our aim was to analyze the results of carotid endarterectomy and carotid artery stent placement in patients with symptomatic carotid near-occlusion and to identify factors related to technical failure, periprocedural complications, and restenosis. MATERIALS AND METHODS: We conducted a multicenter, prospective nonrandomized study. Patients with angiography-confirmed carotid near-occlusion were included. We assessed the revascularization rate and periprocedural stroke or death. Twenty-four-month clinical and carotid imaging follow-up was performed, and rates of carotid restenosis or occlusion, ipsilateral stroke, and mortality were analyzed. Carotid artery stent placement, carotid endarterectomy, and medical treatment were compared. RESULTS: One hundred forty-one patients were included. Forty-four carotid artery stent placement and 23 carotid endarterectomy procedures were performed within 6 months after the event. Complete revascularization was achieved in 83.6%, 81.8% in the carotid artery stent placement group and 87% with carotid endarterectomy (P = .360). Periprocedural stroke or death occurred in 6% (carotid artery stent placement = 2.3%; carotid endarterectomy = 13%; P = .077) and was not related to revascularization failure. The carotid restenosis or occlusion rate was 8.3% (5% restenosis, 3.3% occlusion); with carotid artery stent placement it was 10.5%; and with carotid endarterectomy it was 4.5% (P = .419). The 24-month cumulative rate of ipsilateral stroke was 4.8% in the carotid artery stent placement group, 17.4% for carotid endarterectomy, and 13.1% for medical treatment (P = .223). Mortality was 12%, 4.5%, and 5.6%, respectively (P = .422). Revascularization failure and restenosis occurred more frequently in patients with full collapse compared with patients without full collapse (33.3% versus 5.6%, P = .009; 21.4% versus 2.9%, P = .032, respectively). CONCLUSIONS: Carotid artery stent placement and carotid endarterectomy are associated with high rates of failure and periprocedural stroke. Carotid near-occlusion with full collapse appears to be associated with an increased risk of technical failure and restenosis. Carotid near-occlusion revascularization does not seem to reduce the risk of stroke at follow-up compared with medical treatment.

We report on a search for nuclear recoil signals from solar B8 neutrinos elastically scattering off xenon nuclei in XENON1T data, lowering the energy threshold from 2.6 to 1.6 keV. We develop a variety of novel techniques to limit the resulting increase in backgrounds near the threshold. No significant B8 neutrinolike excess is found in an exposure of 0.6 t×y. For the first time, we use the nondetection of solar neutrinos to constrain the light yield from 1–2 keV nuclear recoils in liquid xenon, as well as nonstandard neutrino-quark interactions. Finally, we improve upon world-leading constraints on dark matter-nucleus interactions for dark matter masses between 3 and 11 GeV c−2 by as much as an order of magnitude.

CIES2020 - XVII Congresso Ibérico e XIII Congresso Ibero-americano de Energia Solar RESUMEN: Los radiómetros absolutos de cavidad (ACR) son los instrumentos de mayor nivel metrológico para la medida de la irradiancia solar directa (DNI), que trabajan según el principio de sustitución eléctrica. Para asegurar su trazabilidad, se comparan (cada 5 años) contra el grupo de patrones WSG que materializan la referencia radiométrica mundial WRR en el PMOD/WRC (Davos, Suiza). Sin embargo, también pueden caracterizarse de forma absoluta mediante la calibración, el modelado y cálculo numérico de todos sus componentes, en base a una ecuación o función de medida, para obtener su incertidumbre total de medida. Este artículo describe distintas tareas realizadas en la caracterización de dos ACR y los resultados preliminares encontrados. En el caso del Eppley AHF, se han calibrado las magnitudes eléctricas y el área de la apertura de precisión, se han determinado la absortancia y el factor de no-equivalencia, así como la dependencia de la corriente en el circuito calefactor de la cavidad con la temperatura. Con estos resultados se esperan alcanzar los objetivos de una incertidumbre inferior a 1000 ppm en DNI y la trazabilidad directa al SI. ABSTRACT: Absolute Cavity Radiometers (ACR) are the instruments, working under the principle of electrical substitution, of the highest metrological level for measuring Direct Normal Irradiance (DNI). To ensure their traceability, they are compared every 5 years in PMOD/WRC (Davos, Switzerland) to the group of standards WSG realizing the World Radiometeric Reference WRR. However, they can also be characterized in an absolute way through the calibration, modelling and numeric simulation of all their components, based on a measurement function, and obtaining their total measurement uncertainty. This paper describes different labors carried out in the characterization of two ACRs and the preliminary results obtained. In the case of the Eppley Labs’ AHF radiometer, the electrical magnitudes and the precision aperture area have been calibrated, effective absorptance and non-equivalence factor have been determined, as well as the dependence on temperature of the electrical current in the heater of the ACR cavity. With these results, the objectives of an uncertainty below 1000 ppm in DNI and the direct traceability to SI can be achieved. info:eu-repo/semantics/publishedVersion

CIES2020 - XVII Congresso Ibérico e XIII Congresso Ibero-americano de Energia Solar RESUMEN: La calibración de la sensibilidad S o responsividad de piranómetros y pirheliómetros, con trazabilidad a la WRR, se realiza mediante procedimientos sencillos descritos en las normas ISO 9847 e ISO 9059, entre otras, que permiten una medida de los sensores y de la irradiancia solar de forma homogénea y equivalente en todo el mundo. La demanda de medidas de irradiancia cada vez más precisas hace necesario mejorar los resultados y fiabilidad de las calibraciones y reducir su incertidumbre, tanto en la parte técnica como en los métodos de medida. En particular, este trabajo analiza la influencia de la temperatura de operación de los pirheliómetros en su sensibilidad y en la irradiancia directa calculada. En base a la experiencia en su calibración, se sugiere la aplicación del mismo método de corrección en S de pirheliómetros que el admitido para piranómetros (ISO 9847), mediante un coeficiente de temperatura lineal. Se muestra el resultado de la aplicación del método en ejemplos reales de calibración y se hacen algunas recomendaciones para fabricantes, sistemas de monitorización y laboratorios de ensayo. ABSTRACT: Calibration of sensitivity S or responsivity of pyranometers and pyrheliometers, traceable to WRR, is performed through simple procedures described in ISO 9847 and ISO 9059 Standards, among others, allowing an homogeneous and equivalent measurement of sensors and of solar irradiance all around the world. The demand for measurements of solar irradiance of increased accuracy makes necessary an improvement on calibration results and reliability and on reducing their uncertainty, both in the technical aspects as in the design of measurement methods. In particular, this work analyzes the influence of operating temperature of pyrheliometers in their sensibility and in the direct irradiance calculated. Application of the same correction method for S as that used for pyranometers (ISO 9847), based on a linear temperature coefficient, is suggested here for pyrheliometers. Results of application of this method on real examples of calibration are shown. Recommendations for manufacturers, monitoring systems and test laboratories are also included. info:eu-repo/semantics/publishedVersion

ispartof: Proceedings of 2020 International Congress on Noise Control Engineering. ispartof: The 49th International Congress and Exposition on Noise Control Engineering location:Seoul status: Published online

Purpose: The aim of this study was to analyse the characteristics of patients with IE in three groups of age and to assess the ability of age and the Charlson Comorbidity Index (CCI) to predict mortality. Methods: Prospective cohort study of all patients with IE included in the GAMES Spanish database between 2008 and 2015. Patients were stratified into three age groups