390 research outputs found

    Single-/Few-Layer Graphene as Long-Lasting Electrocatalyst for Hydrogen Evolution Reaction

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    The development of carbonaceous materials electro-catalytically active for water splitting reactions could overcome multiple disadvantages of metallic catalysts, including high cost, low selectivity, poor durability, and susceptibility to evolved gas. General guidelines to design carbon-based hydrogen evolution reaction (HER) electrocatalysts still remain a topic of debate. Here, we identify single-/few-layer graphene flakes with defective edges (SLG/FLG-DE), produced by hydrogen peroxide-assisted cosolvent liquid phase exfoliation, as durable and efficient HER electrocatalysts. The SLG/FLG-DE display overpotentials at 10 mA cm(-2) of 55 and 85 mV in 0.5 M H2SO4 and 1 M KOH solutions, respectively, as well as a durable HER activity over 200 h

    La enfermedad inflamatoria intestinal y los riesgos de enfermedad cardiovascular

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    La enfermedad inflamatoria intestinal (EII), comprende tanto a la colitis ulcerosa como a la enfermedad de Crohn, entidades consideradas enfermedades inmunomediadas, sistémicas y de curso crónico que conllevan a menudo el desarrollo de manifestaciones extraintestinales. A pesar de que el estudio de las comorbilidades haya sido desarrollado tradicionalmente en contexto de otras enfermedades inflamatorias sistémicas, este concepto está emergiendo también en la EII. Multitud de patologías han sido vinculadas a la EII, entre las que destaca la enfermedad cardiovascular, la primera causa de muerte en los países desarrollados. Los pacientes con EII están expuestos a un mayor riesgo de entidades tales como arterosclerosis precoz e infarto de miocardio, o trombosis venosas y tromboembolismo pulmonar. El objetivo de esta revisión es hacer una aproximación a la fisiopatología de las diferentes manifestaciones de la enfermedad cardiovascular en los pacientes con EII y de cómo prevenirlas. Inflammatory bowel disease (IBD) includes both ulcerative colitis and Crohn's disease, which are well recognised as chronic systemic and immune-mediated conditions that frequently involve extraintestinal manifestations. Although comorbidities have long been the subject of research in other chronic inflammatory diseases, this concept is also emerging in IBD. Many pathologies have been linked to IBD, including cardiovascular disease, which is the main cause of death in developed countries. IBD patients are at increased risk of conditions such as early atherosclerosis and myocardial infarction or venous thrombosis and pulmonary thromboembolism. The aim of this review is to make an approximation of the physiopathology of the different manifestations of cardiovascular disease in patients with IBD and how to prevent them

    A Win–Win Combination to Inhibit Persistent Organic Pollutant Formation via the Co-Incineration of Polyvinyl Chloride E-Waste and Sewage Sludge

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    Persistent organic pollutant inhibition in the combustion process of polyvinyl chloride (PVC) by prior addition of an inhibitor is currently being studied, reducing the emission of pollutants, and thus reducing the large amount of waste PVC destined for landfill. In this work, the use of sewage sludge (SS) as an alternative to chemical inhibitors to improve the quality emissions of the incineration of polyvinyl chloride waste (PVC e-waste) was studied and optimized. Different combustion runs were carried out at 850 °C in a laboratory tubular reactor, varying both the molar ratio Ri (0.25, 0.50, 0.75) between inhibitors (N + S) and chlorine (Cl) and the oxygen ratio λ (0.15, 0.50) between actual oxygen and stoichiometric oxygen. The emissions of several semivolatile compounds families such as polycyclic aromatic hydrocarbons (PAHs), polychlorobenzenes (ClBzs), and polychlorophenols (ClPhs), with special interest in the emissions of the most toxic compounds, i.e., polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs) and dioxin-like polychlorinated biphenyls (dl-PCBs), were analyzed. A notable decrease in PCDD/F and dl-PCB formation was achieved in most of the experiments, especially for those runs performed under an oxygen-rich atmosphere (λ = 0.50), where the addition of sludge was beneficial with inhibition ratios Ri ≥ 0.25. An inhibition ratio of 0.75 showed the best results with almost a 100% reduction in PCDD/F formation and a 95% reduction in dl-PCB formation.Support for this work was granted by CTQ2016-76608-R project and the scholarship BES-2017-080382 from the Ministry of Economy, Industry and Competitiveness (Spain). GC-MS/QQQ used in the analysis was supported by Project IDIFEDER/2018/004 by the Generalitat Valenciana (Spain)

    Friction during earthquakes: 25 years of experimental studies

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    Notas: Export Date: 21 March 2022Dynamic fault strength (rock friction in the broad sense) and its evolution with seismic slip and slip rate are among the most relevant parameters in earthquake mechanics. Given the large slip rate (1 m s-1 on average), displacement (up to tens of meters), effective stress (tens of MPa), typical of seismic faulting at depth, thermo-mechanical effects become outstanding: dynamic fault strength is severely affected by fluid and rock phase changes, extreme grain size reduction, and the production of amorphous and unstable materials in the slipping zone. Here, first we will summarize the most relevant findings about dynamic fault strength during seismic slip mainly obtained thanks to the exploitation of dedicated experimental machines (i.e., rotary shear apparatus). However, the interpretation of this experimental dataset remains debated because of technical limitations which impede us to measure fundamental parameters such as temperature, strain rate, pore fluid pressure and grain size in the slipping zone. Without a sound estimate of these physical parameters, any constitutive law proposed to describe the evolution of dynamic fault strength during simulated seismic slip remains speculative. Then, we will discuss the results of some recent experiments which exploit new technical approaches to overcome the main limitations of the previous studies. The experimental approach, together with field studies of the geometry and architecture of exhumed faults and modelling, remains our most powerful tool to investigate seismic-related deformation mechanisms in both natural and human-induced earthquakes

    Estudio de Prefactibilidad para la Creación de la Empresa Aquaponic Greenhouse System AGS

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    Por tales razones, se definió el presente proyecto, el cual consiste en la creación de una empresa, Aquaponic Greenhouse System (AGS), mediante el uso de todas las herramientas necesarias (estudio de mercado, técnico, financiero) para la incorporación de la misma en el mercado nacional. Dicha empresa tiene como objetivo traer a nuestro país un nuevo sistema productivo (Acuaponía) auto sostenible con tecnologías amigables e inteligentes con el medio ambiente, fomentando así una cultura de alimentación saludable, siendo la primera empresa en Nicaragua que produzca y comercialice a gran escala, con este sistema, productos como vegetales y peces ciento por ciento orgánicos

    Finding answers in lipid profile in COVID-19 patients

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    Introduction: A small percentage of patients will develop a severe form of COVID-19 caused by SARS-CoV-2 infection. Thus, it is important to predict the potential outcomes identifying early markers of poor prognosis. In this context, we evaluated the association of SARS-CoV-2 infection with lipid abnormalities and their role in prognosis. Methods: Single-center, retrospective, observational study of COVID-19 patients admitted from March to October 2020. Clinical and laboratory data, comorbidities, and treatments for COVID-19 were evaluated. Main outcomes including intensive care unit (ICU) admission and mortality were analyzed with a multivariable Cox proportional hazards regression model. Results: We selected 1489 from a total of 2038 consecutive patients with confirmed COVID-19, who had a complete lipid profile before ICU admission. During the follow-up performed in 1109 patients, we observed a decrease in T-c, HDL-c, and LDL-c in 28.6%, 42.9%, and 30.4% of patients, respectively, and an increase in TG in 76.8%. The decrease of both T-c and HDL- c was correlated with a decrease in albumin levels (r = 0.39 and r = 0.37, respectively). Kaplan–Meier survival curves found an increased ICU admission in patients with lower T-c (HR 0.55, CI 0.36–0.86), HDL-c (HR 0.61, CI 0.45–0.84), and LDL-c (HR 0.85, CI 0.74–0.97). Higher values of T-c (HR 0.45, CI 0.36–0.57), HDL-c (HR 0.66, CI 0.54–0.81), and LDL-c (HR 0.86, CI 0.78–0.94) showed a protective effect on mortality. Conclusions: Abnormalities in lipid profile are a frequent complication of SARS-CoV-2 infection and might be related to morbidity and mortalityThis work was supported by the following grants: Proyectos de Investigación en Salud (FIS) PI16-02091 and PI19-00584 (funded by Instituto de Salud Carlos III), TIRONET2-CM, B2017/BMD-3724 (funded by Comunidad de Madrid) and cofinanced by FEDER funds to M.M

    A parallel-group, multicenter randomized, double-blinded, placebo-controlled, phase 2/3, clinical trial to test the efficacy of pyridostigmine bromide at low doses to reduce mortality or invasive mechanical ventilation in adults with severe SARS-CoV-2 infection: the Pyridostigmine In Severe COvid-19 (PISCO) trial protocol

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    © 2020, The Author(s). Background: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, the causative agent of coronavirus disease 2019 (COVID-19), may lead to severe systemic inflammatory response, pulmonary damage, and even acute respiratory distress syndrome (ARDS). This in turn may result in respiratory failure and in death. Experimentally, acetylcholine (ACh) modulates the acute inflammatory response, a neuro-immune mechanism known as the inflammatory reflex. Recent clinical evidence suggest that electrical and chemical stimulation of the inflammatory reflex may reduce the burden of inflammation in chronic inflammatory diseases. Pyridostigmine (PDG), an ACh-esterase inhibitor (i-ACh-e), increases the half-life of endogenous ACh, therefore mimicking the inflammatory reflex. This clinical trial is aimed at evaluating if add-on of PDG leads to a decrease of invasive mechanical ventilation and death among patients with severe COVID-19. Methods: A parallel-group, multicenter, randomized, double-blinded, placebo-controlled, phase 2/3 clinical trial to test the efficacy of pyridostigmine bromide 60 mg/day P.O. to reduce the need for invasive mechanical ventilation and mortality in hospitalized patients with severe COVID-19. Discussion: This study will provide preliminary evidence of whether or not -by decreasing systemic inflammation- add-on PDG can improve clinical outcomes in patients with severe COVID-19. Trial registration: ClinicalTrials.gov NCT04343963 (registered on April 14, 2020)

    Rehabilitación y reforzamiento estructural de pasos a desnivel y puentes

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    EN ESTE TRABAJO SE PROPONE LA REHABILITACION Y REFORZAMIENTO DE ELEMENTOS ESTRUCTURALES, COMO LO SON LOS PASOS A DESNIVEL Y PUENTES, UTILIZANDO PLATINAS DE FIBRA DE CARBONO TENSADAS, LAS CUALES AL ADHERIRSE AL ELEMENTO EN CUESTION EJERCERAN UNA REACION CONTRARIA A LAS FUERZAS QUE PRODUCEN LA APARICION DE LA FLECHA, RECUPERANDO DE ESTA MANERA ESA DEFLEXION O FLECHA PROVOCADA YA SEA POR EL EFECTO TIEMPO, IMCREMENTO DE CARGAS TALES COMO LAS CARGAS MUERTAS Y VIVAS, ETC. AL ALCANZAR ESTA FLECHA CIERTOS NIVELES, SE VE AFECTADA LA FUNCIONABILIDAD DE LA ESTRUCTURA LLEGANDO A PROVOCAR MOLESTIAS A LOS USUARIOS Y DAÑOS EN LOS AUTOMOTORES QUE NECESITAN UTILIZAR ESTOS PASOS DE MANERA COTIDIAN

    Restauración de las olmedas ibéricas (Ulmus minor y U. laevis) en zonas riparias de la Comunidad de Madrid

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    El proyecto LIFE+ “Olmos Vivos” (LIFE13 BIO/ES/000556) tiene como objetivo la restauración de unas formaciones vegetales, las olmedas, que por diversos motivos prácticamente han desaparecido del paisaje forestal español, a pesar de haber poseído un alto valor ecológico y cultural. La grafiosis ha constituido una de las enfermedades forestales más devastadoras, y supuso la práctica desaparición de las olmedas ibéricas de Ulmus minor . En el caso de Ulmus laevis , la alteración de su hábitat ligado a zonas temporalmente encharcadas y riberas ha provocado que las poblaciones españolas se encuentren en riesgo de desaparición. Gracias a la obtención de siete clones de U. minor resistentes a la grafiosis como fruto del Programa del Olmo (UPM-MAGRAMA), el presente proyecto permitirá reintroducir la especie en diversas localizaciones de ribera de los ríos Jarama y Tajo. Asimismo, se plantarán brinzales obtenidos de agrupaciones relícticas de U. laevis , con el fin de aumentar sus poblaciones y conservar sus recursos genéticos, en terrenos de naturaleza silícea de las riberas del río Jarama y Arroyo Viñuelas. El desarrollo del proyecto, de cinco años y tres meses de duración 2014-2019), prevé la plantación de unas 16 700 plantas. Al mismo tiempo se recuperará en nuestras ciudades y pueblos la presencia del olmo, mediante plantaciones con fines divulgativos en entornos urbanos y paseos históricos, para devolver así el protagonismo cultural a un árbol que siempre estuvo entre nosotros, presidiendo las reuniones en las plazas y acompañando con su sombra en muchos caminos de nuestra geografía

    The limbic brain under stress: a role for the LPA1 receptor

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    Adverse events can impact brain structure and function and are considered primary sources of risk for depression, anxiety, and other psychiatric disorders. In this sense, the neurobiological circuitry in charge of dealing with stressors has been widely studied in animal models. Our group has demonstrated a role for lysophosphatidic acid (LPA) through the LPA1-receptor in controlling anxious and depressive states, owing to aggravation of the detrimental consequences of stress in the brain. Indeed, our group has recently proposed the variant maLPA1-null mice, i.e. mice lacking the LPA1 receptor, as an endophenotype for anxious depression. In addition, we have previously reported hyperactivation of key stress-related brain areas after stress, such as basolateral amygdala. Here, we seek to further examine the engagement of the LPA1 receptor in the regulation of the limbic circuit following an acute stressor, tail suspension test, in wildtype and knockout animals. To that end, c-Fos expression was evaluated as a measure of functional activity in both basal and stress conditions, followed by interregional correlation matrices to establish the brain map of functional activation. Additionally, we observed whether one single dose of the antidepressant treatment with desipramine is able to normalize the functional brain map. Results revealed that the absence of the LPA1 receptor induce an anomalous pattern of brain functional activity after TST, which was reverted by desipramine administration.These results provide further insight to the involvement of the LPA1 receptor in stress regulation and shed light on divergent brain pathways under normal and vulnerability conditions that can be implicated in depressive symptoms. Finally, how this pattern might be reverted by antidepressant treatment can be useful for developing new pharmaceutical targets regarding the LPA1 receptor.Funding: Andalusian Ministry of Economy, Innovation, Science and Employment (SEJ1863 to C.P) and of Health (Nicolas Monardes programme, to G.E-T); the Spanish Ministry of Economy and Competitiveness (PSI2013-44901-P to L.J.S. and C.P.). Author R.D. M-F holds a Grant of the Spanish Ministry of Education, Culture and Sports (FPU14/01610). Author S.T. holds a Grant of the Andalusian Ministry of Economy, Innovation, Science and Employment (FPDI 2014). I Plan Propio de Investigación y Transferencia, Universidad de Málaga. Campus de Excelencia. Andalucía Tech
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