2,418 research outputs found

    Functional Glyconanomaterials

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    Nanotechnology provides a new array of techniques and platforms to study biological processes including glycosystems [...

    Measurement of the Total Factor Productivity of Spanish Agriculture: 1962-1989

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    Optical binding-driven micropatterning and photosculpting with silver nanorods

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    Controlling the nano- and micropatterning of metal structures is an important requirement for various technological applications in photonics and biosensing. This work presents a method for controllably creating silver micropatterns by laser-induced photosculpting. Photosculpting is driven by plasmonic interactions between pulsed laser radiation and silver nanorods (AgNRs) in aqueous suspension; this process leads to optical binding forces transporting the AgNRs in the surroundings, while electronic thermalization results in photooxidation, melting, and ripening of the AgNRs into well-defined 3D structures. This work call these structures Airy castles due to their structural similarity with a diffraction-limited Airy disk. The photosculpted Airy castles contain emissive Ag nanoclusters, allowing for the visualization and examination of the aggregation process using luminescence microscopy. This work comprehensively examines the factors that define the photosculpting process, namely, the concentration and shape of the AgNRs, as well as the energy, power, and repetition rate of the laser. Finally, this work investigates the potential applications by measuring the metal-enhanced luminescence of a europium-based luminophore using Airy castles

    Piranoantocianos vinilfenólicos en vinos tintos utilizando levaduras HCDC+.

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    Los piranoantocianos vinilfenólicos son aductos de elevada estabilidad, con interesantes propiedades para la mejora del color en vinos tintos, y que se forman por condensación entre ácidos hidroxicinámicos o sus respectivos vinilfenoles y antocianos procedentes de la uva. Inicialmente se pensaba que la única ruta de formación era exclusivamente química (Schwarz, 2003) en un lento proceso a partir de ácidos hidroxicinámicos, que inducía a cantidades muy pequeñas durante el periodo de envejecimiento de los vinos tintos y podían por tanto ser usadas como age-markers. Recientemente se ha demostrado (Morata et al, 2006 y 2007) que algunas cepas de Saccharomyces spp seleccionadas con alta actividad hidroxicinamato descarboxilasa (HCDC) pueden acelerar la formación de aductos vinilfenólicos durante la fermentación. Estas levaduras descarboxilan los ácidos fenólicos formando vinilfenoles de elevada reactividad que espontáneamente condensan con antocianos de la uva formando una gran variedad de aductos vinilfenólicos dependiendo del tipo de antociano y del ácido hidroxicinámico precursor. Cuantitativamente los derivados más importantes son los del malvidin-3-O-glucosido. Adicionando ácidos hidroxicinámicos a las muestras se verifica que el aducto que se forma en mayor cantidad es el malvidin-3-O-glucosido-4-vinilguaiacol, siendo además el que produce mayor incremento de la intensidad colorante reduciendo a su vez las tonalidades amarillas en vinos. La utilización de cepas de Saccharomyces HCDC+ con o sin adiciones de ácidos hidroxicinámicos, puede constituirse en una interesante herramienta para mejorar el color de vinos tintos

    Caracterización y clasificación de los carbones cretácicos de Teruel. Relaciones entre sus características y el entorno geológico

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    27 páginas, 8 figuras, 4 tablas.[ES]: Se han caracterizado los carbones cretácicos de la cuenca minera de Teruel (España), mediante el estudio exhaustivo de 36 muestras de capa de todas las explotaciones con actividad minera. El estudio ha comprendido: Análisis inmediato, elemental y petrográfico. Asimismo, se han determinado otros parámetros cuyo conocimiento se consideró necesario. También se han realizado ensayos carboquimicos como oxidación e hidrogenación. Los resultados muestran que aunque estos carbones pertenecen todos a una misma unidad geológica (Formación Escucha), existen diferencias claras entre los carbones de las subzonas Norte y Sur del Distrito Minero. Estos carbones se han clasificado mediante sistemas científicos (Seyler, van Krevelen y Alpem-ICCP) y comerciales (ECE/IJN y ASTM). El mejor parámetro clasificatorio ha sido la reflectividad de la vitrinita. Según el sistema de clasificación utilizado, los carbones de la subzona Norte se pueden considerar como lignitos o subbituminosos B y los de la subzona Sur como subbituminosos B ó A. Las diferencias encontradas entre los carbones estudiados, se explican desde un punto de vista geológico, por dos motivos: 1) Diferente presión litostática sobre las capas de carbón según la subzona, debido al aumento progresivo de la potencia de los sedimentos del Cenomaniense - Senoniense (Cretácico Superior) de Norte a Sur del Distrito Minero. 2) Menor influencia de la orogénesis alpina en las subzona Norte, contrastando con la subzona Sur, donde provocó gran número de fallas y plegamientos (una estructuración más intensa de las sucesiones mesozoicas).[EN]: Cretaceous coals from the Teruel Mining District (Spain) have been characterized by an exhaustive study of 36 bed samples from alí of the underground and upen cut mines with activity in that cual field. This study has included proximate, elemental, petrographic and other analyses. Also, sume chemical tests, as oxidations and hydrogenations, have been carried out. The results show that although these coals belung tu the same geological unit (Escucha Furmation in the lower Cretaceous), there are clear differences between the Norther and Southem Subzones of the Mining District. These coals have been classified by sume scientific (Syler’s, van Krevelen diagram and Alpem-ICCP) and commercial (ECE/UN and ASTM) systems. The best parameter tu classify these coals has been the vitrinite reflectance. In depending un the used classification system, cuaN from the North Subzone can be cunsidered as lignites or subbituminous B while coals from the South Subzone can be considered as subbituminous B or A. The differences between both groups uf studied coals can be explained, from a geological viewpoint, by two major factors: 1) The lithostatic pressure supported by the cual beds has been different in depending un the Subzone, because of the progressive thickness increase of te Cenomanian - Senonian sediments (Upper Cretaceous) from the North tu the South uf the Mining District. 2) The intensity of te Alpine Orogeny was stronger in the South Subzone; where gaye rise tu a more intense structuration of the Mesozoic sequences.El proyecto de investigación: “Caracterización de carbones aragoneses” del que forma parte este proyecto, fue realizado en el Instituto de Carboquímica, gracias a la financiación del CSIC, OCICARBON y Diputación General de Aragón - Diputación Provincial de Teruel (Juan, 1990).Peer reviewe

    Paper-based chromatic toxicity bioassay by analysis of bacterial ferricyanide reduction

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    Water quality assessment requires a continuous and strict analysis of samples to guarantee compliance with established standards. Nowadays, the increasing number of pollutants and their synergistic effects lead to the development general toxicity bioassays capable to analyse water pollution as a whole. Current general toxicity methods, e.g. Microtox®, rely on long operation protocols, the use of complex and expensive instrumentation and sample pre-treatment, which should be transported to the laboratory for analysis. These requirements delay sample analysis and hence, the response to avoid an environmental catastrophe. In an attempt to solve it, a fast (15 min) and low-cost toxicity bioassay based on the chromatic changes associated to bacterial ferricyanide reduction is here presented. E. coli cells (used as model bacteria) were stably trapped on low-cost paper matrices (cellulose-based paper discs, PDs) and remained viable for long times (1 month at -20 °C). Apart from bacterial carrier, paper matrices also acted as a fluidic element, allowing fluid management without the need of external pumps. Bioassay evaluation was performed using copper as model toxic agent. Chromatic changes associated to bacterial ferricyanide reduction were determined by three different transduction methods, i.e. (i) optical reflectometry (as reference method), (ii) image analysis and (iii) visual inspection. In all cases, bioassay results (in terms of half maximal effective concentrations, EC50) were in agreement with already reported data, confirming the good performance of the bioassay. The validation of the bioassay was performed by analysis of real samples from natural sources, which were analysed and compared with a reference method (i.e. Microtox). Obtained results showed agreement for about 70% of toxic samples and 80% of non-toxic samples, which may validate the use of this simple and quick protocol in the determination of general toxicity. The minimum instrumentation requirements and the simplicity of the bioassay open the possibility of in-situ water toxicity assessment with a fast and low-cost protocolPostprint (author's final draft

    Early outcomes from the Minimally Invasive Right Colectomy Anastomosis study (MIRCAST)

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    Anastomosis; ColectomyAnastomosi; ColectomiaAnastomosis; ColectomíaBackground The impact of method of anastomosis and minimally invasive surgical technique on surgical and clinical outcomes after right hemicolectomy is uncertain. The aim of the MIRCAST study was to compare intracorporeal and extracorporeal anastomosis (ICA and ECA respectively), each using either a laparoscopic approach or robot-assisted surgery during right hemicolectomies for benign or malignant tumours. Methods This was an international, multicentre, prospective, observational, monitored, non-randomized, parallel, four-cohort study (laparoscopic ECA; laparoscopic ICA; robot-assisted ECA; robot-assisted ICA). High-volume surgeons (at least 30 minimally invasive right colectomy procedures/year) from 59 hospitals across 12 European countries treated patients over a 3-year interval The primary composite endpoint was 30-day success, defined by two measures of efficacy—absence of surgical wound infection and of any major complication within the first 30 days after surgery. Secondary outcomes were: overall complications, conversion rate, duration of operation, and number of lymph nodes harvested. Propensity score analysis was used for comparison of ICA with ECA, and robot-assisted surgery with laparoscopy. Results Some 1320 patients were included in an intention-to-treat analysis (laparoscopic ECA, 555; laparoscopic ICA, 356; robot-assisted ECA, 88; robot-assisted ICA, 321). No differences in the co-primary endpoint at 30 days after surgery were observed between cohorts (7.2 and 7.6 per cent in ECA and ICA groups respectively; 7.8 and 6.6 per cent in laparoscopic and robot-assisted groups). Lower overall complication rates were observed after ICA, specifically less ileus, and nausea and vomiting after robot-assisted procedures. Conclusion No difference in the composite outcome of surgical wound infections and severe postoperative complications was found between intracorporeal versus extracorporeal anastomosis or laparoscopy versus robot-assisted surgery.The MIRCAST Study Group has received research intensification grants from the Regional Government of Cantabria, Spain, and a research grant from Intuitive Surgical (Sunnyvale, CA, USA). MIRCAST was designed and conducted independently at the Valdecilla Biomedical Research Institute (IDIVAL). The funding institutions had no influence in the design or conduct of the study
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