1,137 research outputs found

    Fabrication and characterization of nanostructured porous silicon-silver composite layers by cyclic deposition: Dip-coating vs spin-coating

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    “This is the Accepted Manuscript version of an article accepted for publication in Nanotechnology. IOP Publishing Ltd is not responsible for any errors or omissions in this version of the manuscript or any version derived from it. The Version of Record is available online at https://doi.org/10.1088/1361-6528/ab96e5”Composites of nanostructured porous silicon and silver (nPSi-Ag) have attracted great attention due to the wide spectrum of applications in fields such as microelectronics, photonics, photocatalysis and bioengineering, Among the different methods for the fabrication of nanostructured composite materials, dip and spin-coating are simple, versatile, and cost-effective bottom-up technologies to provide functional coatings. In that sense, we aimed at fabricating nPSi-Ag composite layers. Using nPSi layers with pore diameter of 30 nm, two types of thin-film techniques were systematically compared: cyclic dip-coating (CDC) and cyclic spin-coating (CSC). CDC technique formed a mix of granular and flake-like structures of metallic Ag, and CSC method favored the synthesis of flake-like structures with Ag and Ag2O phases. Flakes obtained by CDC and CSC presented a width of 110 nm and 70 nm, respectively. Particles also showed a nanostructure surface with features around 25 nm. According to the results of EDX and RBS, integration of Ag into nPSi was better achieved using the CDC technique. SERS peaks related to chitosan adsorbed on Ag nanostructures were enhanced, especially in the nPSi-Ag composite layers fabricated by CSC compared to CDC, which was confirmed by FTDT simulations. These results show that CDC and CSC produce different nPSi-Ag composite layers for potential applications in bioengineering and photonicsThis work was financially supported by Fondo Nacional de Desarrollo Científico y Tecnológico FONDECYT–Chile (grant number 11180395), FONDEQUIP–Chile (project 160152

    Antibacterial films of silver nanoparticles embedded into carboxymethylcellulose/chitosan multilayers on nanoporous silicon: A layer-by-layer assembly approach comparing dip and spin coating

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    The design and engineering of antibacterial materials are key for preventing bacterial adherence and proliferation in biomedical and household instruments. Silver nanoparticles (AgNPs) and chitosan (CHI) are broad-spectrum antibacterial materials with different properties whose combined application is currently under optimization. This study proposes the formation of antibacterial films with AgNPs embedded in carboxymethylcellulose/chitosan multilayers by the layer-by-layer (LbL) method. The films were deposited onto nanoporous silicon (nPSi), an ideal platform for bioengineering applications due to its biocompatibility, biodegradability, and bioresorbability. We focused on two alternative multilayer deposition processes: cyclic dip coating (CDC) and cyclic spin coating (CSC). The physicochemical properties of the films were the subject of microscopic, microstructural, and surface–interface analyses. The antibacterial activity of each film was investigated against Escherichia coli (Gram-negative) and Staphylococcus aureus (Gram-positive) bacteria strains as model microorganisms. According to the findings, the CDC technique produced multilayer films with higher antibacterial activity for both bacteria compared to the CSC method. Bacteria adhesion inhibition was observed from only three cycles. The developed AgNPs–multilayer composite film offers advantageous antibacterial properties for biomedical applicationsPID2020-112770RB-C2

    Comparison of the impact of nesofilcon A hydrogel contact lens on the ocular surface and the comfort of presbyopic and non-presbyopic wearers

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    AIM: To assess and compare the impact of a daily disposable contact lens (CL) with high water content on the ocular surface and comfort of the presbyopic and non-presbyopic population after one day of use. METHODS: Totally 20 presbyopes and 30 non-presbyopes non-contact wearers were fitted with nesofilcon A CLs. CL thickness was measured to assess material stability during daily wear, and ocular surface parameters were also assessed. Optical quality was analyzed for all cases. In addition, CL comfort was rated. RESULTS: No significant differences were found in CL thickness, tear film osmolarity, average tear break-up time, bulbar redness, central corneal thickness, corneal volume, root-mean-square of higher-order aberrations (RMS of HOAs) and vertical and horizontal coma, either as a function of the group or time of use. A significant decrease in tear meniscus height and first break-up of the tear film was found in the presbyopic group (P=0.038; P=0.007 respectively). A decrease in spherical aberration coefficient was found after CL insertion (P=0.031 monofocal CL; P=0.023 low addition multifocal CL; P=0.016 high addition multifocal CL). Multifocal CL were thicker than monofocal CL (P=0.045). Comparison between groups showed more discomfort in presbyopes than non-presbyopes (P=0.003). CONCLUSION: This study evidence that the behavior of the daily disposable CL with high water content seems to be stable during the day of use. Ocular parameters measured during wear show that CL behavior is the same for presbyopes and non-presbyopes, being more uncomfortable for presbyopes

    Implantación de un visor GIS con software libre en la Comunidad de Regantes del Trasvase Tajo-Segura de Totana, Murcia

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    En el ámbito del desarrollo de software orientado a la implementación de sistemas de información geográfica, una de las empresas de referencia a nivel internacional es la multinacional estadounidense Esri. En particular, en el contexto de los visores cartográficos para la web, por la experiencia del usuario que aportan. No obstante, la utilización de visores, tal y como los ofrece Esri en su sitio web, queda circunscrita al consumo de servicios ArcGIS Server, que sólo se pueden gestionar mediante la aplicación de Esri ArcGIS for Server. El elevado coste de la adquisición de este software propicia, en muchos casos, la búsqueda de soluciones alternativas, que casi siempre pasan por la utilización de librerías de desarrollo de código abierto, como son OpenLayers, GeoExt y ExtJS, entre otras. En este trabajo se plantea una propuesta que aprovecha las características funcionales del visor de Esri, evitando recurrir a ArcGIS for Server como servidor de mapas. Esto es posible gracias a la generación de servicios WMS y WFS a partir de software libre (servidores de mapas MapServer o GeoServer) y, al hecho de que Esri mantenga liberado bajo la licencia Apache 2.0 el código de su visor, permitiendo la alteración del código, lo que permite implementar capacidades funcionales nuevas, como la recuperación interactiva de datos temáticos (operación GetFeatureInfo en servicios WMS) y las búsquedas multicriterio sobre el mapa (operación GetFeature en servicios WFS). Este visor de La Compañía® ha sido implantado con éxito en la Comunidad de Regantes del Trasvase Tajo-Segura de Totana en Murcia, poniendo de manifiesto de que con software libre es posible construir visores con las mismas y/o mejores funcionalidades que los visores implementados con software propietario, y reforzar las ventajas en el ahorro de costes aplicando software libre, logrando con ello independencia tecnológica de las empresas que comercializan software propietario

    Aplicación de un programa informatizado para emitir informes clínicos en la asignatura de Clínica Optométrica I

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    El objetivo es optimizar el uso de un programa informático de registro y almacenamiento de datos clínicos y la creación de una nueva herramienta para generar informes clínicos. Los informes clínicos forman parte de la evaluación del alumno

    Development of an activity disease score in patients with uveitis (UVEDAI)

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    To develop a disease activity index for patients with uveitis (UVEDAI) encompassing the relevant domains of disease activity considered important among experts in this field. The steps for designing UVEDAI were: (a) Defining the construct and establishing the domains through a formal judgment of experts, (b) A two-round Delphi study with a panel of 15 experts to determine the relevant items, (c) Selection of items: A logistic regression model was developed that set ocular inflammatory activity as the dependent variable. The construct "uveitis inflammatory activity" was defined as any intraocular inflammation that included external structures (cornea) in addition to uvea. Seven domains and 15 items were identified: best-corrected visual acuity, inflammation of the anterior chamber (anterior chamber cells, hypopyon, the presence of fibrin, active posterior keratic precipitates and iris nodules), intraocular pressure, inflammation of the vitreous cavity (vitreous haze, snowballs and snowbanks), central macular edema, inflammation of the posterior pole (the presence and number of choroidal/retinal lesions, vascular inflammation and papillitis), and global assessment from both (patient and physician). From all the variables studied in the multivariate model, anterior chamber cell grade, vitreous haze, central macular edema, inflammatory vessel sheathing, papillitis, choroidal/retinal lesions and patient evaluation were included in UVEDAI. UVEDAI is an index designed to assess the global ocular inflammatory activity in patients with uveitis. It might prove worthwhile to motorize the activity of this extraarticular manifestation of some rheumatic diseases

    The Fourteenth Data Release of the Sloan Digital Sky Survey: First Spectroscopic Data from the extended Baryon Oscillation Spectroscopic Survey and from the second phase of the Apache Point Observatory Galactic Evolution Experiment

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    The fourth generation of the Sloan Digital Sky Survey (SDSS-IV) has been in operation since July 2014. This paper describes the second data release from this phase, and the fourteenth from SDSS overall (making this, Data Release Fourteen or DR14). This release makes public data taken by SDSS-IV in its first two years of operation (July 2014-2016). Like all previous SDSS releases, DR14 is cumulative, including the most recent reductions and calibrations of all data taken by SDSS since the first phase began operations in 2000. New in DR14 is the first public release of data from the extended Baryon Oscillation Spectroscopic Survey (eBOSS); the first data from the second phase of the Apache Point Observatory (APO) Galactic Evolution Experiment (APOGEE-2), including stellar parameter estimates from an innovative data driven machine learning algorithm known as "The Cannon"; and almost twice as many data cubes from the Mapping Nearby Galaxies at APO (MaNGA) survey as were in the previous release (N = 2812 in total). This paper describes the location and format of the publicly available data from SDSS-IV surveys. We provide references to the important technical papers describing how these data have been taken (both targeting and observation details) and processed for scientific use. The SDSS website (www.sdss.org) has been updated for this release, and provides links to data downloads, as well as tutorials and examples of data use. SDSS-IV is planning to continue to collect astronomical data until 2020, and will be followed by SDSS-V.Comment: SDSS-IV collaboration alphabetical author data release paper. DR14 happened on 31st July 2017. 19 pages, 5 figures. Accepted by ApJS on 28th Nov 2017 (this is the "post-print" and "post-proofs" version; minor corrections only from v1, and most of errors found in proofs corrected

    Revista de Vertebrados de la Estación Biológica de Doñana

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    Catálogo descriptivo de los anfibios y reptiles de CubaEvolución estacional de la comunidad de aves en un robledal de Sierra NevadaComposición de la comunidad de aves en pinares del Parque Nacional de Doñana (suroeste de España).Alimentación de la pagaza piconegra (Gelochelidon nilotica) en las marismas del GuadalquivirContaminación xenobiótica del Parque Nacional de Doñana. III. Residuos de insecticidas organoclorados, bifenilos policlorados y metales pesados en ciconiformesAlimentación de la lechuza común Tyto alba en la cuenca del Duero, EspañaEstudio de una población rural de (Mus musculus L.) I. La probabilidad de captura y la estima numéricLa reproducción en Gazella dorcasIncidencia del Nemátodo parásito Skrjabingylus Leuckart, 1842 sobre el Mustela en España.Desplazamientos de ungulados silvestres a través de una zona de ecotono en Doñana.Etograma de la cabra montés (Capra pyrenaica) y comparación con otras especies.Sobre comportamiento agresivo de Triturus marmoratus en época de celoEmbarrancamiento masivo de ejemplares de tortuga lad (Dermochelys coriacea L.) en las costas de Ceuta (España, norte de África)Sobre un ejemplar melánico de Podarcis hispanica (Steindachner, 1870)Nuevos datos sobre la distribución de cuatro especies de reptiles en la provincia de Cádiz.Algunos datos sobre la nidificación de Ciconia nigra L. en sierra Morena (S. España)Observación del halcón de Eleonor (Falco eleonorae) en el centro de EspañaNueva localidad de cría del pájaro moscón (Remiz pendulinus) en la Península IbéricaRegistro de aves en el sur de BoliviaNidificación del paiño de Madeira Oceanodroma castro (Harcourt, 1851) en las Islas Canarias.Observación primaveral de Phalaropus fulicarius L. en el SO de EspañaNuevos datos sobre la presencia del nóctulo gigante Nyctalus lasiopterus (Chiroptera, vespertilionidae) en EspañaNote sur l'alimentation de Martes martes a Menorca (Baleares).Peer reviewe
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