82 research outputs found

    Dynamic reflective color pixels based on molybdenum oxide

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    Active materials which show phase transitions, usually known as Phase Change Materials (PCM), have paved the way to a new generation of reconfigurable plasmonic platforms. Tunable color devices have experienced a great development in the recent years. In particular, reflective color filters can take advantage from sunlight to select and reflect a specific resonant wavelength in the visible spectrum range. Reflective displays are usually structural color filters based on asymmetric Fabry-Perot cavities (AFPCs). For a fixed geometry, most of AFPCs filters generate static color, limiting their potential as tunable color devices. Dynamic color is achieved by introducing an active layer whose optical properties can be modulated by an external stimuli. In this paper, we propose AFPCs based on molybdenum oxide (MoOx, 2<x<3) to achieve switchable on/off color reflective pixels. On and off states of the pixels are controlled through the stoichiometry of the MoOx layer.This work has received funding from the European Union’s Horizon 2020 research and innovation program under grant agreement (No 899598 – PHEMTRONICS)

    Gold nanodoughnut as an outstanding nanoheater for photothermal applications

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    Photoinduced hyperthermia is a cancer therapy technique that induces death to cancerous cells via heat generated by plasmonic nanoparticles. While previous studies have shown that some nanoparticles can be effective at killing cancer cells under certain conditions, there is still a necessity (or the need) to improve its heating efficiency. In this work, we perform a detailed theoretical study comparing the thermoplasmonic response of the most effective nanoparticle geometries up to now with a doughnut-shaped nanoparticle. We numerically demonstrate that the latter exhibits a superior tunable photothermal response in practical illumination conditions (unpolarized light). Furthermore, we show that nanoparticle heating in fluidic environments, i.e., nanoparticles undergoing Brownian rotations, strongly depends on the particle orientation with respect to the illumination source. We conclude that nanodoughnuts are the best nanoheaters in our set of structures, with an average temperature increment 40% higher than the second best nanoheater (nanodisk). Furthermore, nanodoughnuts feature a weak dependence on orientation, being therefore ideal candidates for photothermal therapy applications. Finally, we present a designing guide, covering a wide range of toroid designs, which can help on its experimental implementation.Acknowledgments. Authors would like to thank A. Franco and C. R. Crick for the interesting discussions. We gratefully acknowledge financial support from Spanish national project (No. PGC2018-096649-B-I), the UK Leverhulme Turst (Grant No. RPG-2018-384), UK-EPSRC (EP/J003859/1) and Imperial College Europeans Partner Fund grant. J. G-C. thanks the Ministry of science of Spain for his FPI grant. G. S. thanks the Ministry of education for his collaboration grant and P.A. acknowledges funding for a Ramon y Cajal Fellowship (Grant No. RYC-2016-20831)

    The UV plasmonic behavior of distorted rhodium nanocubes

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    For applications of surface-enhanced spectroscopy and photocatalysis, the ultraviolet (UV) plasmonic behavior and charge distribution within rhodium nanocubes is explored by a detailed numerical analysis. The strongest plasmonic hot-spots and charge concentrations are located at the corners and edges of the nanocubes, exactly where they are the most spectroscopically and catalytically active. Because intense catalytic activity at corners and edges will reshape these nanoparticles, distortions of the cubical shape, including surface concavity, surface convexity, and rounded corners and edges, are also explored to quantify how significantly these distortions deteriorate their plasmonic and photocatalytic properties. The fact that the highest fields and highest carrier concentrations occur in the corners and edges of Rh nanocubes (NCs) confirms their tremendous potential for plasmon-enhanced spectroscopy and catalysis. It is shown that this opportunity is fortuitously enhanced by the fact that even higher field and charge concentrations reside at the interface between the metal nanoparticle and a dielectric or semiconductor support, precisely where the most chemically active sites are located.This research has been supported by MICINN (Spanish Ministry of Science and Innovation, project FIS2013-45854-P). Research was sponsored by the Army Research Laboratory and was accomplished under Cooperative Agreement Number W911NF-17-2-0023. Y.G. wants to thank the University of Cantabria for her FPU (formación del profesorado universitario) gran

    Los Poyos del Molinillo (Frigiliana): new site of the Bronze Age in the East Axarquía (Málaga, Andalucía)

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    En este trabajo damos a conocer un nuevo yacimiento descubierto recientemente en el municipio de Frigiliana. La delimitación del área denominada Los Poyos del Molinillo permitió definir la existencia de un poblado y una covacha con restos de una inhumación. El estudio de los materiales arqueológicos, que incluye cerámica, piezas metálicas o elementos de molturación, o la datación AMS obtenida, permiten adscribir el yacimiento a la Edad del Bronce y ampliar el conocimiento de esta etapa en la Axarquía oriental (Málaga, Andalucía).In this work we present a new site recently discovered in the Frigiliana municipality (Málaga). The spatial delimitation of the so called Los Poyos del Molinillo area let us define a Bronze age settlement and an inhumation burial cave. The archaeological record includes ceramic, metallic items or grinding elements, all of them belonging to the Bronze Age, as well as an AMS Radiocarbon data. This site extends the knowledge about this period in the Eastern Axarquía (Málaga, Andalucía)

    Los socios de la RSEHN y el desarrollo de las colecciones científicas del MNCN

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    Valencia, del 8 al 11 de septiembre de 2021. El tema principal tuvo como lema: “La huella Humana en la Naturaleza”.Las colecciones científicas son una infraestructura de investigación única e irremplazable para numerosas áreas de la ciencia. En la actualidad, se estima que en el Museo Nacional de Ciencias Naturales se conservan 10 millones de especímenes, lo que suponen casi la mitad de todos los conservados en España. Esta infraestructura científica o este tesoro, como puede ser llamado, se ha reunido principalmente a lo largo del último siglo, y se debe al trabajo conjunto de muchos especialistas, estudiosos e interesados en diferentes disciplinas de las ciencias naturales. En esta ponencia se quiere poner en valor la aportación de los socios de la RSEHN en el incremento y desarrollo de las colecciones científicas del MNCN. Se ha realizado un análisis preliminar de los fondos de las diferentes colecciones del MNCN y de los ingresos efectuados por los socios de RSEHN desde su fundación (1871) hasta el momento en que abandona el MNCN (1971). Se realizó en cada una de ellas una consulta de los diferentes colectores y personas que aportaron especímenes y que aparecen en las bases de datos, cruzándola con la base de datos de socios durante dicho periodo. Se ha contabilizado el número de especímenes, número de tipos y taxones correspondientes a éstos. La cifra de socios total supera el centenar. El número de ejemplares ingresados por estos socios, entre esas fechas, se estima que superan el millón y medio, lo que supone al menos un 15% del total actual estimado. Hay que tener en cuenta que las colecciones no se encuentran informatizadas al 100%

    Neuroblastoma RAS viral oncogene homolog (N-RAS) deficiency aggravates liver injury and fibrosis.

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    Progressive hepatic damage and fibrosis are major features of chronic liver diseases of different etiology, yet the underlying molecular mechanisms remain to be fully defined. N-RAS, a member of the RAS family of small guanine nucleotide-binding proteins also encompassing the highly homologous H-RAS and K-RAS isoforms, was previously reported to modulate cell death and renal fibrosis; however, its role in liver damage and fibrogenesis remains unknown. Here, we approached this question by using N-RAS deficient (N-RAS-/-) mice and two experimental models of liver injury and fibrosis, namely carbon tetrachloride (CCl4) intoxication and bile duct ligation (BDL). In wild-type (N-RAS+/+) mice both hepatotoxic procedures augmented N-RAS expression in the liver. Compared to N-RAS+/+ counterparts, N-RAS-/- mice subjected to either CCl4 or BDL showed exacerbated liver injury and fibrosis, which was associated with enhanced hepatic stellate cell (HSC) activation and leukocyte infiltration in the damaged liver. At the molecular level, after CCl4 or BDL, N-RAS-/- livers exhibited augmented expression of necroptotic death markers along with JNK1/2 hyperactivation. In line with this, N-RAS ablation in a human hepatocytic cell line resulted in enhanced activation of JNK and necroptosis mediators in response to cell death stimuli. Of note, loss of hepatic N-RAS expression was characteristic of chronic liver disease patients with fibrosis. Collectively, our study unveils a novel role for N-RAS as a negative controller of the progression of liver injury and fibrogenesis, by critically downregulating signaling pathways leading to hepatocyte necroptosis. Furthermore, it suggests that N-RAS may be of potential clinical value as prognostic biomarker of progressive fibrotic liver damage, or as a novel therapeutic target for the treatment of chronic liver disease

    Healthcare workers hospitalized due to COVID-19 have no higher risk of death than general population. Data from the Spanish SEMI-COVID-19 Registry

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    Aim To determine whether healthcare workers (HCW) hospitalized in Spain due to COVID-19 have a worse prognosis than non-healthcare workers (NHCW). Methods Observational cohort study based on the SEMI-COVID-19 Registry, a nationwide registry that collects sociodemographic, clinical, laboratory, and treatment data on patients hospitalised with COVID-19 in Spain. Patients aged 20-65 years were selected. A multivariate logistic regression model was performed to identify factors associated with mortality. Results As of 22 May 2020, 4393 patients were included, of whom 419 (9.5%) were HCW. Median (interquartile range) age of HCW was 52 (15) years and 62.4% were women. Prevalence of comorbidities and severe radiological findings upon admission were less frequent in HCW. There were no difference in need of respiratory support and admission to intensive care unit, but occurrence of sepsis and in-hospital mortality was lower in HCW (1.7% vs. 3.9%; p = 0.024 and 0.7% vs. 4.8%; p<0.001 respectively). Age, male sex and comorbidity, were independently associated with higher in-hospital mortality and healthcare working with lower mortality (OR 0.211, 95%CI 0.067-0.667, p = 0.008). 30-days survival was higher in HCW (0.968 vs. 0.851 p<0.001). Conclusions Hospitalized COVID-19 HCW had fewer comorbidities and a better prognosis than NHCW. Our results suggest that professional exposure to COVID-19 in HCW does not carry more clinical severity nor mortality

    Circulating carotenoids are associated with favorable lipid and fatty acid profiles in an older population at high cardiovascular risk

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    Carotenoid intake has been reported to be associated with improved cardiovascular health, but there is little information on actual plasma concentrations of these compounds as biomarkers of cardiometabolic risk. The objective was to investigate the association between circulating plasma carotenoids and different cardiometabolic risk factors and the plasma fatty acid profile. This is a cross-sectional evaluation of baseline data conducted in a subcohort (106 women and 124 men) of an ongoing multi-factorial lifestyle trial for primary cardiovascular prevention. Plasma concentrations of carotenoids were quantified by liquid chromatography coupled to mass spectrometry. The associations between carotenoid concentrations and cardiometabolic risk factors were assessed using regression models adapted for interval-censored variables. Carotenoid concentrations were cross-sectionally inversely associated with serum triglyceride concentrations [-2.79 mg/dl (95% CI: -4.25, -1.34) and -5.15 mg/dl (95% CI: -7.38, -2.93), p-values = 0.0002 and <0.00001 in women and men, respectively], lower levels of plasma saturated fatty acids [-0.09% (95% CI: -0.14, -0.03) and -0.15 % (95% CI: -0.23, -0.08), p-values = 0.001 and 0.0001 in women and men, respectively], and higher levels of plasma polyunsaturated fatty acids [(0.12 % (95% CI: -0.01, 0.25) and 0.39 % (95% CI: 0.19, 0.59), p-values = 0.065 and 0.0001 in women and men, respectively] in the whole population. Plasma carotenoid concentrations were also associated with higher plasma HDL-cholesterol in women [0.47 mg/dl (95% CI: 0.23, 0.72), p-value: 0.0002], and lower fasting plasma glucose in men [-1.35 mg/dl (95% CI: -2.12, -0.59), p-value: 0.001]. Keywords: Mediterranean diet; PREDIMED-plus study; cardiovascular health; liquid chromatography; mass spectrometry; plasma carotenoids
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