Diffusion of single dye molecules in hydrated TiO 2 mesoporous films

Mesoporous oxide films are attractive frameworks in technological areas such as catalysis, sensing, environmental protection, and photovoltaics. Herein, we used fluorescence correlation spectroscopy to explore how the pore dimensions of hydrated TiO2 mesoporous calcined films modulate the molecular diffusion. Rhodamine B molecules in mesoporous films follow a Fickian process 2–3 orders slower compared to the probe in water. The mobility increases with the pore and neck radii reaching an approximately constant value for a neck radius >2.8 nm. However, the pore size does not control the dye diffusion at low ionic strength emphasizing the relevance of the probe interactions with the pore walls on dye mobility. In conclusion, our results show that the thermal conditioning of TiO2 mesoporous films provides an exceptional tool for controlling the pore and neck radii on the nanometer scale and has a major impact on molecular diffusion within the mesoporous network.Fil: Angiolini, Juan Francisco. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales; ArgentinaFil: Stortz, Martin Dario. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Fisiología, Biología Molecular y Neurociencias. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Fisiología, Biología Molecular y Neurociencias; ArgentinaFil: Steinberg, Paula Yael. Comisión Nacional de Energía Atómica. Centro Atómico Constituyentes; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Mocskos, Esteban Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Centro de Simulación Computacional para Aplicaciones Tecnológicas; ArgentinaFil: Bruno, Luciana. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Física de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Física de Buenos Aires; ArgentinaFil: Soler Illia, Galo Juan de Avila Arturo. Universidad Nacional de San Martin. Instituto de Nanosistemas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Angelome, Paula Cecilia. Comisión Nacional de Energía Atómica. Centro Atómico Constituyentes; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Wolosiuk, Alejandro. Comisión Nacional de Energía Atómica. Centro Atómico Constituyentes; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Química Inorgánica, Analítica y Química Física; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Levi, Valeria. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales; Argentin

Microstructure and corrosion evolution of additively manufactured aluminium alloy AA7075 as a function of ageing

Additively manufactured high strength aluminium alloy AA7075 was prepared using selective laser melting. High strength aluminium alloys prepared by selective laser melting have not been widely studied to date. The evolution of microstructure and hardness, with the attendant corrosion, were investigated. Additively manufactured AA7075 was investigated both in the as-produced condition and as a function of artificial ageing. The microstructure of specimens prepared was studied using electron microscopy. Production of AA7075 by selective laser melting generated a unique microstructure, which was altered by solutionising and further altered by artificial ageing - resulting in microstructures distinctive to that of wrought AA7075-T6. The electrochemical response of additively manufactured AA7075 was dependent on processing history, and unique to wrought AA7075-T6, whereby dissolution rates were generally lower for additively manufactured AA7075. Furthermore, immersion exposure testing followed by microscopy, indicated different corrosion morphology for additively manufactured AA7075, whereby resultant pit size was notably smaller, in contrast to wrought AA7075-T6.Comment: 37 pages, includes 4 Tables and 11 Figure

Trajectory Reconstruction Techniques for Evaluation of ATC Systems

This paper is focused on trajectory reconstruction techniques for evaluating ATC systems, using real data of recorded opportunity traffic. We analyze different alternatives for this problem, from traditional interpolation approaches based on curve fitting to our proposed schemes based on modeling regular motion patterns with optimal smoothers. The extraction of trajectory features such as motion type (or mode of flight), maneuvers profile, geometric parameters, etc., allows a more accurate computation of the curve and the detailed evaluation of the data processors used in the ATC centre. Different alternatives will be compared with some performance results obtained with simulated and real data sets

Efecto de las medidas del BCE sobre los márgenes de intereses en España

En la etapa actual, las perspectivas de bajos niveles de rentabilidad de las entidades financieras parten del primer escalón de la cuenta de resultados, del margen de intereses. Este trabajo se ha centrado en analizar el margen de intereses del sector bancario español en el contexto europeo. Los bancos operan con márgenes de intereses muy estrechos en Europa. De hecho, en la eurozona, Alemania, Francia e Italia, el margen de intermediación no llega a cubrir los gastos de explotación de los grupos consolidados. El margen de intereses de los grupos consolidados en España se ha situado sistemáticamente por encima del resto de grandes países de la Eurozona. Este trabajo cuantifica la importancia de los distintos determinantes del margen de intermediación a través de un ejercicio de simulación. De acuerdo con nuestros resultados, la actual coyuntura de bajos tipos de interés está afectando negativamente al margen de intereses, pues este es el factor que mayor influencia tiene. En estos momentos en los que la rentabilidad bancaria está en entredicho, una subida de tipos de interés supondría un balón de oxígeno para las entidades bancarias. Les permitiría afrontar los retos estructurales a los que se enfrentan en mejores condiciones. Sin embargo, teniendo en cuenta que los indicios disponibles no inducen a pensar que en el corto plazo el BCE vaya a implementar una política monetaria radicalmente distinta con subidas rápidas de tipos de interés, el reto de aumentar la rentabilidad en el contexto de bajos tipos de interés continuará. En este sentido tres elementos son esenciales: la contención de costes y mejoras de eficiencia que permitan mejorar los resultados incluso con los tipos de interés actuales; la capacidad de generación de ingresos distintos a los intereses; y la continuidad de la mejora de la coyuntura macroeconómica que permita seguir reduciendo la parte del resultado que se detrae por las provisiones

Molecular Dynamics Simulations to Study Drug Delivery Systems

Molecular dynamics simulation is a very powerful tool to understand biomolecular processes. In this chapter, we go over different applications of this methodology to drug delivery systems (DDS) carried out in the group. DDS—a formulation or a device that enables the introduction of a therapeutic substance in the body and improves its efficacy and safety by controlling the rate, time, and place of release of drugs—are an important component of drug development and therapeutics. Biocompatible nanoparticles are materials in the nanoscale that emerged as important players, improving efficacy of approved drugs, for example. The molecular understanding of the encapsulation process could be very helpful to guide the nanocarrier for a specific system. Here we discuss different applications of drug delivery carriers, such as liposomes, polymeric micelles, and polymersomes using atomistic and coarse grain (CG) molecular dynamics simulations

Amorphous Al-Ti Powders Prepared by Mechanical Alloying and Consolidated by Electrical Resistance Sintering

A novel processing method for amorphous Al50Ti50 alloy, obtained by mechanical alloying and subsequently consolidated by electrical resistance sintering, has been investigated. The characterisation of the powders and the confirmation of the presence of amorphous phase have been carried out by laser diffraction, scanning electron microscopy, X-ray diffraction, differential scanning calorimetry and transmission electron microscopy. The amorphous Al50Ti50 powders, milled for 75 h, have a high hardness and small plastic deformation capacity, not being possible to achieve green compacts for conventional sintering. Moreover, conventional sintering takes a long time, being not possible to avoid crystallisation. Amorphous powders have been consolidated by electrical resistance sintering. Electrically sintered compacts with different current intensities (7–8 kA) and processing times (0.8–1.6 s) show a porosity between 16.5 and 20%. The highest Vickers hardness of 662 HV is reached in the centre of an electrically sintered compact with 8 kA and 1.2 s from amorphous Al50Ti50 powder. The hardness results are compared with the values found in the literature.Ministerio de Economía y Competitividad (Spain) / Feder (EU) DPI2015-69550-C2-1-PMinisterio de Economía y Competitividad (Spain) / Feder (EU) DPI2015-69550-C2-2-

Modeling of urban enviromental problems using geographic information systems and multivariate methods.

En el presente documento se hace una descripción general de una propuesta metodológica para la modelización de problemas ambientales urbanos, utilizando una combinación de Sistemas de Información Geográfica y técnicas numéricas para generar escenarios probables de impacto. Se presenta como ejemplo una aplicación específica a la creación de mapas de escenarios de susceptibilidad a deslizamientos de tierra en una ciudad intermedia colombiana. Específicamente, se hace una descripción breve de la necesidad de buscar métodos transversales de análisis para las realidades complejas que constituyen los entornos urbanos, uno de ellos (entre muchos existentes) constituido por el fenómeno de deslizamientos de tierra en ciudades andinas, y a partir de ello, se propone una metodología basada en el análisis multifactorial de causas, que aprovecha experiencias pasadas para proponer escenarios futuros posibles, aprovechando las ventajas ofrecidas por los Sistemas de Información Geográfica para manejar información, y las Redes Neuronales Artificiales para clasificar datos.In the present work a methodological proposal is presented for modeling urban environmental problems. It combines Geographic Information Systems and numerical techniques in order to generate probable impact scenarios. Additionally, a specific application is presented as an example oriented to creating susceptibility maps of landslides risk scenarios in an intermediate Colombian city. More specifically, the necessity of finding transversal methods to analyze the complex urban realities is presented. Among these realities, we pick up the possibility of landslides in Andes cities and a whole methodology based on a multifactorial cause analysis is introduced. This methodology takes into account past experiences to propose possible futures scenarios, relying on both Geographic Information Systems to store data and on Artificial Neural Networks to classify them

Using machine learning methods to determine a typology of patients with HIV-HCV infection to be treated with antivirals

Several European countries have established criteria for prioritising initiation of treatment in patients infected with the hepatitis C virus (HCV) by grouping patients according to clinical characteristics. Based on neural network techniques, our objective was to identify those factors for HIV/HCV co-infected patients (to which clinicians have given careful consideration before treatment uptake) that have not being included among the prioritisation criteria. This study was based on the Spanish HERACLES cohort (NCT02511496) (April-September 2015, 2940 patients) and involved application of different neural network models with different basis functions (product-unit, sigmoid unit and radial basis function neural networks) for automatic classification of patients for treatment. An evolutionary algorithm was used to determine the architecture and estimate the coefficients of the model. This machine learning methodology found that radial basis neural networks provided a very simple model in terms of the number of patient characteristics to be considered by the classifier (in this case, six), returning a good overall classification accuracy of 0.767 and a minimum sensitivity (for the classification of the minority class, untreated patients) of 0.550. Finally, the area under the ROC curve was 0.802, which proved to be exceptional. The parsimony of the model makes it especially attractive, using just eight connections. The independent variable "recent PWID" is compulsory due to its importance. The simplicity of the model means that it is possible to analyse the relationship between patient characteristics and the probability of belonging to the treated group