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Towards a Personalised Health System
This paper presents a Personalized Healthcare System (PHS), a decision support tool that can adapt to changing conditions, such as aging and illness, in individual patients. The system consists of three components: a unique personalised profile, a collection of web based tools and a web based repository for managing interactions between clinicians and tools. The proposed system makes extensive use of software agents, both for collecting the initial information required to construct a personalized profile and for transporting the information needed to use the on-line decision support tools. The paper discusses the operation of a PHS and suggests possible implementation issues
FeNi-based magnetoimpedance multilayers: Tailoring of the softness by magnetic spacers
The microstructure and magnetic properties of sputtered permalloy films and FeNi(170 nm)/X/FeNi(170 nm) (X=Co, Fe, Gd, Gd-Co) sandwiches were studied. Laminating of the thick FeNi film with various spacers was done in order to control the magnetic softness of FeNi-based multilayers. In contrast to the Co and Fe spacers, Gd and Gd-Co magnetic spacers improved the softness of the FeNi/X/FeNi sandwiches. The magnetoimpedance responses were measured for [FeNi/Ti(6 nm)] 2/FeNi and [FeNi/Gd(2 nm)] 2/FeNi multilayers in a frequency range of 1-500 MHz: for all frequencies under consideration the highest magnetoimpedance variation was observed for [FeNi/Gd(2 nm)] 2/FeNi multilayers. © 2012 American Institute of Physics
Development of low-pH cementitious materials for HLRW repositories. Resistance against ground waters aggression
One of the most accepted engineering construction concepts of underground repositories for high radioactive waste considers the use of low-pH cementitious materials. This paper deals with the design of those based on Ordinary Portland Cements with high contents of silica fume and/or fly ashes that modify most of the concrete “standard” properties, the pore fluid composition and the microstructure of the hydrated products. Their resistance to long-term groundwater aggression is also evaluated. The results show that the use of OPC cement binders with high silica content produces low-pH pore waters and the microstructure of these cement pastes is different from the conventional OPC ones, generating C–S–H gels with lower CaO/SiO2 ratios that possibly bind alkali ions. Leaching tests show a good resistance of low-pH concretes against groundwater aggression although an altered front can be observe
Exploring Deep Learning Image Super-Resolution for Iris Recognition
In this work we test the ability of deep learning methods to provide an
end-to-end mapping between low and high resolution images applying it to the
iris recognition problem. Here, we propose the use of two deep learning
single-image super-resolution approaches: Stacked Auto-Encoders (SAE) and
Convolutional Neural Networks (CNN) with the most possible lightweight
structure to achieve fast speed, preserve local information and reduce
artifacts at the same time. We validate the methods with a database of 1.872
near-infrared iris images with quality assessment and recognition experiments
showing the superiority of deep learning approaches over the compared
algorithms.Comment: Published at Proc. 25th European Signal Processing Conference,
EUSIPCO 201
Los depósitos de ceniza volcánica del Pleistoceno Superior-Holoceno de la región de Tafí del Valle-Cafayate, noroeste de Argentina
[EN]We identified volcanic ash deposits, whose thickness can exceed sometimes the 4 m, in the southeastern margin of La Puna and neighbouring areas (Provinces of Tucuman and Salta, Argentina). These Late Pleistocene and Holocene deposits show the existence of a highly explosive volcanism only some few thousand years ago, without comparison with any historical volcanic episode in northwestern Argentina. We have characterized the size distribution of ash (laser diffraction), morphology of particles (SEM), mineralogy (XRD) and the geochemistry of major and trace elements in bulk sample using mass spectrometry (HR-ICP-MS). The information provided by these deposits is of great interest to size adequately the geochemical impact models of ashfall in future volcanic eruptions in the Central Volcanic Zone of the Andes, quantifying the contribution of volcanic ash to the regional geochemical balances, both with respect to nutrients (e.g., Ca and Fe) and potentially toxic elements (e.g., As and F), among other elements of interest.[ES] Se han localizado diversos depósitos de ceniza volcánica, cuyos espesores llegan a superar en ocasiones los 4 m al suroeste de La Puna y áreas limítrofes (Provincias de Tucumán y Salta, Argentina). Estos depósitos son de edad Pleistoceno Superior y Holoceno y muestran la existencia hace pocos miles de años de volcanismo altamente explosivo, sin comparación con ningún episodio volcánico histórico en el noroeste de Argentina. Se han caracterizado la distribución granulométrica de la ceniza (difracción laser), la morfología de las partículas (microscopía electrónica de barrido), mineralogía (difracción de rayos X) y la geoquímica de elementos mayores y trazas en muestra total mediante espectrometría de masas (HR-ICP-MS). La información suministrada por estos depósitos tiene gran interés a la hora de dimensionar los modelos de impacto geoquímico de la caída de ceniza de futuras erupciones volcánicas en la Zona Volcánica Central de los Andes, cuantificando la contribución de la ceniza volcánica a los balances geoquímicos regionales, tanto por lo que respecta a nutrientes (p. ej., Ca y Fe), como de elementos potencialmente tóxicos (p. ej., As y F), entre otros elementos de interés.Agradecemos el apoyo técnico del labGEOTOP (infraestructura cofinanciada por FEDER, CSIC08-4E-001) del ICTJA-CSIC; de los Grupos PEGEFA (2009-SGR-972) y GEOVOL y fue financiado por el Proyecto QUECA (CGL2011-23307).Peer reviewe
Ocular accommodation and wavelength: The effect of longitudinal chromatic aberration on the stimulus-response curve.
The longitudinal chromatic aberration (LCA) of the eye creates a chromatic blur on the retina that is an important cue for accommodation. Although this mechanism can work optimally in broadband illuminants such as daylight, it is not clear how the system responds to the narrowband illuminants used by many modern displays. Here, we measured pupil and accommodative responses as well as visual acuity under narrowband light-emitting diode (LED) illuminants of different peak wavelengths. Observers were able to accommodate under narrowband light and compensate for the LCA of the eye, with no difference in the variability of the steady-state accommodation response between narrowband and broadband illuminants. Intriguingly, our subjects compensated more fully for LCA at nearer distances. That is, the difference in accommodation to different wavelengths became larger when the object was placed nearer the observer, causing the slope of the accommodation response curve to become shallower for shorter wavelengths and steeper for longer ones. Within the accommodative range of observers, accommodative errors were small and visual acuity normal. When comparing between illuminants, when accommodation was accurate, visual acuity was worst for blue narrowband light. This cannot be due to the sparser spacing for S-cones, as our stimuli had equal luminance and thus activated LM-cones roughly equally. It is likely because ocular LCA changes more rapidly at shorter wavelength and so the finite spectral bandwidth of LEDs corresponds to a greater dioptric range at shorter wavelengths. This effect disappears for larger accommodative errors, due to the increased depth of focus of the eye
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