Study of the Indentation Process under Specific Technological Parameters

AbstractThere is a large variety of Compressive Forming Processes with different typologies and characteristics. In this paper, the indentation process is studied from the point of view of manufacturing. The influence of technological parameters such as friction and shape factor on the process has been studied. The aluminum alloy AA 6082 has been employed in this study due to its good mechanical properties, light weight and its capacity of being recycled. The Finite Element Method (FEM) has been used for the analysis. The indentation process has been studied under axisymmetric conditions. The forces to carry out the indentation process and the contact pressures have been obtained. Finally, it is shown that the forces and the contact pressures do not have a high dependency on the friction between the surfaces of the punch and the workpiece. The shape factor has a greater influence on the process, especially the width of the workpiece

Study of the Indentation Process under Specific Technological Parameters

AbstractThere is a large variety of Compressive Forming Processes with different typologies and characteristics. In this paper, the indentation process is studied from the point of view of manufacturing. The influence of technological parameters such as friction and shape factor on the process has been studied. The aluminum alloy AA 6082 has been employed in this study due to its good mechanical properties, light weight and its capacity of being recycled. The Finite Element Method (FEM) has been used for the analysis. The indentation process has been studied under axisymmetric conditions. The forces to carry out the indentation process and the contact pressures have been obtained. Finally, it is shown that the forces and the contact pressures do not have a high dependency on the friction between the surfaces of the punch and the workpiece. The shape factor has a greater influence on the process, especially the width of the workpiece

Comparative Analysis of Extrusion Processes by Finite Element Analysis

AbstractExtrusion processes are quite extended in the manufacturing of long products for a wide range of industrial applications. There are different approaches of extrusion processes, depending on either the final shape of the product to obtain or the maximum loading capacity of the equipment to be used. This work presents a comparative study of extrusion processes (solid and cup extrusion), considering both direct and indirect forming conditions and showing the most interesting differences between them. The comparison is realized by Finite Element simulation of the processes, using the code DEFORM F2. The material is a low carbon steel (AISI-1010) and the same extrusion ratio and ram displacement are considered in all cases. By comparing the required forces it can be concluded that required loads are higher in cup extrusion processes than in solid extrusion ones. Regarding the friction load, the maximum contribution due to the die-billet contact in cup extrusion is much higher than in the case of solid extrusion. On the contrary, the maximum friction load contribution due to the container wall is much higher in the case of solid extrusion than in cup extrusion

Sentinel-3 MWR Microwave Radiometer – Our contribution to the success of the Copernicus programme

Revista oficial de la Asociación Española de Teledetección[EN] The MWR builds, together with the SRAL altimeter, the S3 topography mission. The MWR, developed by EADS CASA Espacio as prime contractor, provides information for tropospheric path correction of SRAL measurements. MWR data can also be used for determining surface emissivity and soil moisture over land, surface energy budget investigations and ice characterization. The MWR instrument is a Noise Injection Radiometer (NIR), working at two frequencies (23.8/36.5 GHz), embarking a dual frequency horn antenna pointing to the cold sky for embedded autonomous calibration.[ES] El radiómetro MWR, desarrollado por EADS CASA Espacio, constituye la misión topográfica de Sentinel-3 (S3) junto al radar altímetro SRAL. Su función es la entrega de información auxiliar para la corrección troposférica de las medidas del SRAL. Sus datos también pueden servir para caracterizar magnitudes físicas del suelo y la criosfera, así como para la evaluación de balances energéticos. El MWR es un radiómetro de inyección de ruido (NIR) que funciona a dos frecuencias (23,8 y 36,5 GHz) e incorpora una bocina para la obtención de la temperatura de brillo del cielo como medio de calibración autónoma.Los autores querrían agradecer el apoyo y la contribución por parte de los clientes del MWR (ESA y TAS-F), así como de los principales subcontratistas, TAS-E, CRISA, TAS-I, CDE, RYMSA, COBHAM, HVS, ABSL, APCO, IABG e ITD.Palacios, M.; Bergadà, M.; González, R.; Gamonal, A.; García-Fernández, J.; Camacho, Y. (2014). El radiómetro de microondas MWR de Sentinel-3: Nuestra contribución al éxito de Copernicus. Revista de Teledetección. (41):79-88. doi:10.4995/raet.2014.2294.SWORD798841Aguirre, M., Berruti, B., Bezy, J.L., Drinkwater, M., Heliere, F., Klein, U., Mavrocordatos, C., Silvestrin, P., Greco, B., Benveniste, J., 2007. Sentinel-3. The Ocean and Medium-Resolution Land Mission for GMES Operational Services. ESA bulletin, 131, 24-29.Guijarro, J., Auriol, A., Costes, M., Jayles, C., Vincent, P., 2000. MWR & DORIS-Supporting Envisat Radar Altimetry Mission, ESA bulletin, 104, 41-46.L'Abbate, M., Bombaci, O., Alberti, G., Femenias, P., 2003. ENVISAT-1 MWR, in flight functional and performance verification. En: Proceedings of Envisat Validation Workshop, Frascati (Italy).Xie, Y., Chen, J., Liu, D., Lv, C., Liu, K., & Miao, J. (2013). DEVELOPMENT AND CALIBRATION OF A K-BAND GROUND-BASED HYPERSPECTRAL MICROWAVE RADIOMETER FOR WATER VAPOR MEASUREMENTS. Progress In Electromagnetics Research, 140, 415-438. doi:10.2528/pier1305070

Seroreversion of IgG anti-HEV in HIV cirrhotic patients: A long-term multi-sampling longitudinal study

The aim of our study was to evaluate HEV antibody kinetics in HIV/HCV-coinfected patients with cirrhosis. A longitudinal retrospective study was designed. Patients were followed up every 6 months; anti-HEV IgG and IgM antibodies levels and HEV-RNA by qPCR were analysed. The prevalence and incidence of every HEV infection marker were calculated. The kinetics of anti-HEV IgG and IgM during the follow-up were evaluated. Seventy-five patients comprised the study population. The seroprevalence observed was 17.3%. None showed IgM antibodies or HEV-RNA at baseline. None showed detectable HEV viral load during the study period. After a median follow-up of 5.1 years, two of 62 seronegative patients (3.2%) seroconverted to IgG antibody. The incidence for IgM was 2.7%. Of the 13 patients with IgG seropositivity at baseline, five (38.5%) seroreverted. Meanwhile, of the two patients who exhibited IgM positivity during the study, one (50%) showed intermittent positivity. We found that HEV seropositivity is common in HIV/HCV-coinfected cirrhotic patients. A remarkable rate of IgG seroreversions and IgM intermittence was found, limiting the use of antibodies for the diagnosis of HEV infection in this population

GESTIÓN ÓPTIMA DE REDES DE RIEGO MEDIANTE EL CONTROL DE LA OPERACIÓN DE LOS PUNTOS CRÍTICOS

[ES] La necesidad de disminuir los costes energéticos que los agricultores tienen que afrontar tras la modernización de los sistemas de distribución del agua, está llevando a un aumento de la demanda de estrategias encaminadas a reducir el consumo de este recurso. En este trabajo se propone una metodología fundamentada en la optimización de la altura manométrica en la estación de bombeo y el control de la operación de los puntos críticos con el fin de disminuir la demanda energética de la red, asegurando una presión mínima en los hidrantes operativos. La estrategia considera dos escenarios de gestión: escenario A, en el que se determina la altura manométrica óptima considerando un 100 % de simultaneidad de hidrantes; y escenario B, en el que se determina la altura manométrica óptima cuando los hidrantes críticos (identificados previamente) se desactivan. La metodología se ha aplicado en los 11 sectores que componen la comunidad de regantes del Bembézar Margen Derecha, determinando una reducción en la altura manométrica óptima entre los escenarios A y B de 12 m y 13 m en dos sectores seleccionados como representativos. Esta reducción en la altura manométrica se traduce en un ahorro energético potencial de 23.2 % y 25.8 % en los sectores analizados. La adopción del escenario A en las horas en las que el precio de la energía es mayor y la aplicación del escenario B sin restricciones horarias pueden suponer importantes ahorros en el coste energético.Fernández García, I.; González Perea, R.; Rodríguez Díaz, J.; Moreno, M.; Montesinos, P.; Camacho Poyato, E. (2015). GESTIÓN ÓPTIMA DE REDES DE RIEGO MEDIANTE EL CONTROL DE LA OPERACIÓN DE LOS PUNTOS CRÍTICOS. En XXXIII CONGRESO NACIONAL DE RIEGOS. Valencia 16-18 junio de 2015. Editorial Universitat Politècnica de València. https://doi.org/10.4995/CNRiegos.2015.1451OC

Efficacy and safety of switching to abacavir/lamivudine (ABC/3TC) plus rilpivirine (RPV) in virologically suppressed HIV-infected patients on HAART.

We analysed the efficacy and safety of switching from a regimen based on nonnucleoside reverse transcriptase inhibitors (NNRTI) or integrase inhibitors (INI) to ABC/3TC + RPV in virologically suppressed HIV-infected patients. This multicentre, retrospective study comprised asymptomatic HIV-infected patients who switched from 2 NRTI + NNRTI or 2 NRTI + INI to ABC/3TC + RPV between February 2013 and December 2013; all had undetectable HIV viral load prior to switching. Efficacy and safety, and changes in lipids and cardiovascular risk (CVR) were analysed at 48 weeks. Of 85 patients (74.1 % men, mean age 49.5 years), 83 (97.6 %) switched from a regimen based on NNRTI (EFV 74, RPV 5, ETV 2, NVP 2), and 45 (53 %) switched from TDF/FTC to ABC/3TC. The main reasons for switching were toxicity (58.8 %) and convenience (29.4 %). At 48 weeks, 78 (91.8 %) patients continued taking the same regimen; efficacy was 88 % by intention to treat, and 96 % by per protocol. Two patients were lost to follow-up and five ceased the new regimen (4 due to adverse effects and 1 virologic failure). Mean CD4 cell counts increased (744 vs. 885 cells/μL; p = 0.0001), and there were mean decreases in fasting total cholesterol (-15.9 mg/dL; p < 0.0001) and LDL-cholesterol (-11.0 mg/dL; p < 0.004), with no changes in HDL-cholesterol, triglycerides, total cholesterol:HDL-cholesterol ratio, and CVR. ABC/3TC + RPV is effective and safe in virologically-suppressed patients on antiretroviral therapy (ART). Forty-eight weeks after switching the lipid profile improved with decreases in total and LDL cholesterol.This study has been supported in part by the RD12/0017/0017 project (Plan Nacional R+D+ I) and cofinanced by Instituto de Salud Carlos III-Subdirección General de Evaluación y el Fondo Europeo de Desarrollo Regional and a grant from by Janssen Cilag

A functional IL1RL1 variant regulates corticosteroid-induced sST2 expression in ulcerative colitis

Indexación: Web of Science; Scopus.The ST2/IL33 signalling pathway has been associated with ulcerative colitis (UC). ST2, encoded by the IL1RL1 gene, is expressed as both a membrane-anchored receptor (ST2L) activated by IL33 and as a soluble receptor (sST2) with anti-inflammatory properties. In UC patients, sST2 is further increased by corticosteroid treatment; however, the glucocorticoid-mediated molecular regulation remains unknown. We therefore tested whether genetic variants in the IL1RL1 distal promoter are involved in UC and affect glucocorticoid-mediated ST2 expression. Serum ST2 levels and genetic variants in the IL1RL1 distal promoter were examined by ELISA and PCR sequencing in UC patients receiving corticosteroids. Glucocorticoid-mediated ST2 production was evaluated in intestinal mucosa cultures. Molecular regulation of glucocorticoid-mediated ST2 was assessed by RT-qPCR, ChIP assay and luciferase reporter assay. Dexamethasone effect on ST2 transcript expression was analyzed in leukocytes and related to IL1RL1 variants. Sequencing of a distal IL1RL1 promoter region demonstrated that SNPs rs6543115(C) and rs6543116(A) are associated with increased sST2 in UC patients on corticosteroids. Dexamethasone up-regulated sST2 transcription through interaction with the glucocorticoid-response element (GRE) carrying rs6543115(C) variant. Our data indicate that IL1RL1 SNPs rs6543115(C) confer susceptibility to UC and is contained in the GRE, which may modulate glucocorticoid-induced sST2 expression.https://www.nature.com/articles/s41598-017-10465-