22 research outputs found

    FeN4 active sites generated on dipyridylpyridazine functionalized reduced graphene oxide for high-performance air electrode in a Zn-air battery

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    The growing global electricity demand requires the development of cost-effective energy conversion and storage systems, integrating inexpensive, eco-friendly, and high-efficiency catalysts. Oxygen reduction reaction (ORR) is considered crucial process to achieve high-power-density fuel cells and Zn-air batteries (ZABs). The latter have attracted the attention of scientific community due to its high theoretical energy density, reliable safety and low-cost. However, several limitations must be overcome, designing ORR catalysts thought versatile and economical synthetic routes. In this sense, the non-noble iron–nitrogen-carbon materials (Fesingle bondNsingle bondC) have been reported as the most potential candidates for attaining superior activity toward ORR in substitution of the high-priced commercial Pt-C catalysts. Herein, Diels-Alder surface adducts based on dipyridylpyridazine units have been created along 2D surface of reduced graphene oxide (rGO) nanosheets for the controlled generation of FeN4 active sites at the edges through successive solvent-free mechanochemical reactions and an additional thermal treatment. The optimized catalyst provided high content of pyridinic-N, graphitic-N and Fe2+ species, contributing to the excellent activity delivered as electrocatalyst for ORR processes. In addition, a flooded ZAB assembled with this material as cathodic/air electrode exhibited excellent specific capacities of 4.94 and 2.77 A·h·g−1 at -1 and -5 mA, respectively, improving the catalytic performance obtained for the 10 wt% Pt-C benchmark electrocatalyst

    Antiretroviral recommendations may influence the rate of transmission of drug-resistant HIV type 1

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    Producción CientíficaHuman immunodeficiency virus (HIV) treatment guidelines have evolved, shifting from more-aggressive to more-conservative approaches. The potential impact of these shifts on the transmission of drug-resistant virus is unknown. Drug-resistance genotypes were examined in all consecutive patients with recent HIV type 1 (HIV-1) seroconversion (hereafter, "HIV-1 seroconverters") seen at 10 Spanish hospitals since 1997. During the same period, the proportion of patients with chronic HIV-1 infection having undetectable viremia was examined, to estimate the extent and effectiveness of antiretroviral therapy. A total of 141 recent HIV-1 seroconverters were identified, 67.4% of whom were men who have sex with men. The rate of primary drug-resistance mutations, by year of infection, was 33.3% for 1997, 29.4% for 1998, 20% for 1999, 14.3% for 2000, 3.4% for 2001, 15.4% for 2002, and 10.9% for 2003. On the other hand, the proportion of 8388 persons with chronic HIV-1 carriage who had an undetectable virus load was 33.4% for 1997, 34.6% for 1998, 39.7% for 1999, 47.5% for 2000, 52.9% for 2001, 39.7% for 2002, and 58.1% for 2003. A significant inverse correlation between transmission of drug-resistant HIV-1 and undetectable virus load was found (r=-0.955, by Spearman's test; P=.001). The lowest rate of transmission of drug-resistant HIV-1 was seen in 2001, when relatively "aggressive" treatment guidelines were used. Transmission of drug-resistant HIV-1 increased in 2002, in parallel with a reduction in the number of patients with chronic HIV-1 carriage and undetectable virus load, reflecting the popularity of drug holidays or treatment interruptions. The rate of drug resistance in recent HIV-1 seroconverters inversely correlates with the proportion of chronically HIV-1-infected individuals who have undetectable virus loads in the same region, which indirectly reflects antiretroviral treatment rules at any given time

    Resistance to Nonnucleoside Reverse-Transcriptase Inhibitors and Prevalence of HIV Type 1 Non-B Subtypes Are Increasing among Persons with Recent Infection in Spain

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    Producción CientíficaThe prevalence of drug resistance mutations was 12.1% among 198 persons who experienced human immunodeficiency virus (HIV) seroconversion identified in Spain during 1997–2004. There was a significant increase of K103N and of non-B subtypes over time. Transmission of HIV infection around the time of seroconversion was shown in 8 couples and in 2 clusters of 3 individualsRed de Investigación en SIDA (RIS- project 17

    Long-term follow-up of certolizumab pegol in uveitis due to immune-mediated inflammatory diseases : multicentre study of 80 patients

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    Objectives To evaluate effectiveness and safety of certolizumab pegol (CZP) in uveitis due to immune-mediated inflammatory diseases (IMID). Methods Multicentre study of CZP-treated patients with IMID uveitis refractory to conventional immunosuppressant. Effectiveness was assessed through the following ocular parameters: best-corrected visual acuity, anterior chamber cells, vitritis, macular thickness and retinal vasculitis. These variables were compared between the baseline, and first week, first, third, sixth months, first and second year. Results We studied 80 (33 men/47 women) patients (111 affected eyes) with a mean age of 41.6±11.7 years. The IMID included were: spondyloarthritis (n=43), Behçet's disease (n=10), psoriatic arthritis (n=8), Crohn's disease (n=4), sarcoidosis (n=2), juvenile idiopathic arthritis (n=1), reactive arthritis (n=1), rheumatoid arthritis (n=1), relapsing polychondritis (n=1), Conclusions CZP seems to be effective and safe in uveitis related to different IMID, even in patients refractory to previous biological drugs

    Golimumab in refractory uveitis related to spondyloarthritis. Multicenter study of 15 patients

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    Objective: To assess the efficacy of golimumab (GLM) in refractory uveitis associated to spondyloarthritis (SpA). Methods: Multicenter study of SpA-related uveitis refractory to at least one immunosuppressive drug. The main outcome variables were degree of anterior and posterior chamber inflammation, visual acuity, and macular thickness. Results: Fifteen patients (13 men/2 women; 18 affected eyes; mean age 39±6 years) were evaluated. The underlying SpA subtypes were ankylosing spondylitis (n=8), psoriatic arthritis (n=6) and non-radiographic axial SpA (n=1). The ocular involvement patterns were recurrent anterior uveitis in 8 patients and chronic anterior uveitis in 7. Before GLM they have received methotrexate (n=13), sulfasalazine (n=6), pulses of methylprednisolone (n=4), azathioprine (n=3), leflunomide (n=2) and cyclosporine (n=1). Ten of them had also been treated with TNF-? blockers; etanercept (n=7), adalimumab (n=7), infliximab (n=6), and certolizumab (n=1). GLM was given at the standard dose (50 mg/sc/monthly) as monotherapy (n=7) or in combination with conventional immunosuppressive drugs (n=8), mainly methotrexate. Most patients had rapid and progressive improvement of intraocular inflammation parameters. The median number of cells in the anterior chamber at 2 years (0 [0-0]) was significantly reduced compared to baseline findings (1 [0-3]); p=0.04). The mean best corrected visual acuity value also improved (0.84±0.3 at 2 years versus 0.62±0.3 at baseline; p=0.03). Only minor side effects were observed after a mean follow-up of 23±7 months. Conclusions: Our results indicate that GLM may be a useful therapeutic option in refractory SpA-related uveitis

    Conocimientos del CAD - AR342 - 202102

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    Descripción: Curso específico en la carrera de Arquitectura y el primer curso de la mención en Tecnologías Digitales. La competitividad del mundo actual valora de manera excepcional el tiempo, como el recurso más importante, escaso y no recuperable. La efectividad con que comuniquemos visualmente nuestras ideas usando tecnologías digitales, será un punto clave en el camino a lograr nuestros objetivos de automatizar y acelerar nuestros proyectos. Estos objetivos son cimentados en una adecuada asesoría en la elaboración de una maqueta digital y física que genere alto impacto significativo en el desarrollo del proyecto arquitectónico. Propósito: 1El curso de Conocimiento del CAD ha sido diseñado con el propósito de permitir al futuro arquitecto desarrollar habilidades que lo formen en la comprensión de los fundamentos y del valor de la comunicación digital dentro del contexto de la representación asistida por computadora (CAD), del Modelado de la Información (BIM - Building Information Modeling) y de la Fabricación Digital. Todo ello con el fin de potenciar su desarrollo profesional a través de la exploración con tecnologías digitales. Con esta asignatura se busca contribuir al desarrollo de la competencia específica Técnica y Construcción (que corresponde a los criterios NAAB :SC1, SC4, SC6) en el nivel 1. Tiene como requisito haber aprobado 57 créditos

    Conocimiento del CAD - AR243 - 202101

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    Descripción: Curso específico en la carrera de Arquitectura y el primer curso de la mención en Tecnologías Digitales. La competitividad del mundo actual valora de manera excepcional el tiempo, como el recurso más importante, escaso y no recuperable. La efectividad con que comuniquemos visualmente nuestras ideas usando tecnologías digitales, será un punto clave en el camino a lograr nuestros objetivos de automatizar y acelerar nuestros proyectos. Estos objetivos son cimentados en una adecuada asesoría en la elaboración de una maqueta digital y física que genere alto impacto significativo en el desarrollo del proyecto arquitectónico. 1Propósito: El curso de Conocimiento del CAD ha sido diseñado con el propósito de permitir al futuro arquitecto desarrollar habilidades que lo formen en la comprensión de los fundamentos y del valor de la comunicación digital dentro del contexto de la representación asistida por computadora (CAD), del Modelado de la Información (BIM - Building Information Modeling) y de la Fabricación Digital. Todo ello con el fin de potenciar su desarrollo profesional a través de la exploración con tecnologías digitales. Con esta asignatura se busca contribuir al desarrollo de la competencia específica Técnica y Construcción (que corresponde a los criterios NAAB :SC1, SC4, SC6) en el nivel 1. Tiene como requisito haber aprobado 57 créditos
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