Non-noticeable information embedding in color images: marking and detection

One of the problems arising from the use of digital media is the ease of obtaining identical copies of digital images or audio files, allowing manipulation and unauthorized use. Copyright is an effective tool for preserving intellectual property of those documents but authors and publishers need effective techniques preventing copyright modification, due to the straightforward access to multimedia applications and the wider use of digital publications through the WWW. These techniques are generally called watermarking and allow the introduction of side information (i.e. author identification, copyrights, dates, etc.). This work concentrates on the problem of watermarking embedding and optimum detection in color images through the use of spread spectrum techniques, both in space (direct sequence spread spectrum or DSSS) and frequency (frequency hopping). It is applied to RGB and opponent color component representations. Perceptive information is considered in both color systems. Some tests are performed in order to ensure imperceptibility and to assess detection quality of the optimum color detectors.Peer ReviewedPostprint (published version

Recorrido sobre las lenguas del Chaco y los aportes a la investigación lingüística

El Chaco es una de las regiones más ricas de América del Sur, no sólo desde el punto de vista ecológico, sino en términos de su diversidad etnolingüística. Este artículo ofrece primero un panorama actualizado sobre las lenguas chaqueñas y su clasificación genealógica así como un estado del arte de las obras publicadas sobre las lenguas del Chaco argentino. Después de reseñar los estudios sobre sintaxis en las lenguas chaqueñas anteriores a este volumen de Amerindia, las autoras se centran en los planteos teóricos que emergen del estudio de la cláusula y las relaciones interclausales en esta área lingüística, haciendo hincapié en los sistemas de alineamiento, las clases de palabras, sus límites y superposiciones, la relacionalidad de los sustantivos, los distintos tipos de cláusulas y de predicados, los procesos de combinación de verbos y de enlace entre cláusulas a nivel oracional y discursivo. Por último, pasan revista a los aspectos en los cuales los trabajos compilados contribuyen a la discusión y profundización de todos esos temas.Fil: Golluscio, Lucia Angela. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Saavedra 15. Centro Argentino de Información Científica y Tecnológica; Argentina. Universidad de Buenos Aires. Facultad de Filosofía y Letras; ArgentinaFil: Vidal, Alejandra Silvia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste; Argentina. Universidad Nacional de Formosa. Facultad de Humanidades. Instituto de Investigaciones Lingüísticas; Argentin

Repeatability and reproducibility of corneal thickness using SOCT Copernicus HR

Purpose: The aim of this study is to determine the reliability of corneal thickness measurements derived from SOCT Copernicus HR (Fourier domain OCT). Methods: Thirty healthy eyes of 30 subjects were evaluated. One eye of each patient was chosen randomly. Images were obtained of the central (up to 2.0 mm from the corneal apex) and paracentral (2.0 to 4.0 mm) cornea. We assessed corneal thickness (central and paracentral) and epithelium thickness. The intra-observer repeatability data were analysed using the intra-class correlation coefficient (ICC) for a range of 95 per cent within-subject standard deviation (SW) and the within-subject coefficient of variation (CW). The level of agreement by Bland–Altman analysis was also represented for the study of the reproducibility between observers and agreement between methods of measurement (automatic versus manual). Results: The mean value of the central corneal thickness (CCT) was 542.4 ± 30.1 μm (SD). There was a high intra-observer agreement, finding the best result in the central sector with an intra-class correlation coefficient of 0.99, 95 per cent CI (0.989 to 0.997) and the worst, in the minimum corneal thickness, with an intra-class correlation coefficient of 0.672, 95 per cent CI (0.417 to 0.829). Reproducibility between observers was very high. The best result was found in the central sector thickness obtained both manually and automatically with an intra-class correlation coefficient of 0.990 in both cases and the worst result in the maximum corneal thickness with an intra-class correlation coefficient of 0.827. The agreement between measurement methods was also very high with intra-class correlation coefficient greater than 0.91. On the other hand the repeatability and reproducibility for epithelial measurements was poor. Conclusion: Pachymetric mapping with SOCT Copernicus HR was found to be highly repeatable and reproducible. We found that the device lacks an appropriate ergonomic design as proper focusing of the laser beam onto the cornea for anterior segment scanning required that patients were positioned slightly farther away from the machine head-rest than in the setup for retinal imaging

Salivary immunity and lower respiratory tract infections in non-elite marathon runners

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Análisis de la sensibilización de los jóvenes ante la seguridad vial

Decenes Jornades de Foment de la Investigació de la FCHS (Any 2004-2005)Con nuestra investigación pretendemos diseñar un programa de prevención de accidentes a partir del estudio de una realidad concreta. Para ello hemos analizado la sensibilización hacia el uso de medidas de seguridad vial en adolescentes en función de tres variables: la vivencia o no de un accidente, la gravedad del mismo y el grado de parentesco. Los resultados obtenidos, en contra de lo esperado, constatan que la sensibilización no está relacionada inequívocamente con ellas, a excepción de los hermanos en cuanto al grado de parentesco y leve en cuanto a la gravedad.The aim of our research is to design a program to prevent traffic accidents. This syllabus is based on real facts. For it, we have analyzed the sensitizing towards the use of road safety measures, taking into account three variables; having or not an accident, the gravity of it, and the degree of relationship with the person who has had the accident. The outcomes we got are quite different as we expect to. The results state that the sensitizing is not related to any of these three variables, with the exception of their brothers or sisters have suffered the accident and whether the accident is not serious

Métricas para la creatividad, y su enfoque para la enseñanza en las universidades

Ponencia presentada en el XIII Congreso Internacional de Ingeniería de Proyectos celebrado en Badajoz , 8-10 de julio de 2009Creativity is a complex, unpredictable and uncontrollable reality a priori. For that reason, its evaluation seems to be complex, this is, how can creativity be measured? Present work pretends to answer this question through the study of different creativity metrics from three different points of view: creative individual, creative process, and creative product. It is pretended to put this metrics into practice within the educational field in universities. This creativity evaluation can be perceived as thread that can damage creativity. However, the fact of knowing the necessary criterions for measure his own creativity and its results can be considered as an essential help for professors can distinguish those that is creative from that is not, and for students can know the criterions that will be used to evaluate them, so consequently that can get better results.La creatividad es una realidad compleja, impredecible e incontrolable, a priori. Por ello, su evaluación se prevé como compleja, es decir, ¿cómo se puede medir la creatividad? El presente trabajo pretende dar respuesta a esta pregunta a través del estudio de las diferentes métricas para la creatividad enfocadas desde tres puntos de vista diferentes: el individuo creativo, el proceso creativo y el producto creativo. Estas métricas pretenden ser puestas en práctica en el ámbito docente universitario. Esta evaluación de la creatividad puede ser percibida como una amenaza que puede dañar la creatividad, sin embargo, conocer los criterios necesarios para medir la propia creatividad y la de sus resultados se puede considerar como una ayuda imprescindible para que el profesor pueda distinguir aquello creativo de lo que no lo es, y para los alumnos para que puedan conocer los criterios por los que serán evaluados y, a consecuencia, obtener mejores resultados

Genetic dissection of NK cell responses

The association of Natural Killer (NK) cell deficiencies with disease susceptibility has established a central role for NK cells in host defence. In this context, genetic approaches have been pivotal in elucidating and characterizing the molecular mechanisms underlying NK cell function. To this end, homozygosity mapping and linkage analysis in humans have identified mutations that impact NK cell function and cause life-threatening diseases. However, several critical restrictions accompany genetic studies in humans. Studying NK cell pathophysiology in a mouse model has therefore proven a useful tool. The relevance of the mouse model is underscored by the similarities that exist between cell-structure-sensing receptors and the downstream signaling that leads to NK cell activation. In this review, we provide an overview of how human and mouse quantitative trait locis (QTLs) have facilitated the identification of genes that modulate NK cell development, recognition, and killing of target cells

Análisis de la sensibilización de los jóvenes ante la seguridad vial. Bases para la elaboración de un programa. [Analysis of road safety awareness in young people. Bases for the development of a road safety programme]

This research aims to establish the foundations for a traffic accident prevention programme, based on a study of specific circumstances. To this end, we analysed awareness of road safety measure use in young people according to three variables; whether they had any experience of an accident; if so, how serious the accident was, and how close the kinship relation was to the person who had the accident. The findings did not confirm our expectations, but showed that awareness is not clearly related to any of these three variables, except where either a brother or sister was involved in the accident and when the accident was not serious. Con nuestra investigación pretendemos aproximar las bases para el diseño de un programa de prevención de accidentes, a partir del estudio de una realidad concreta. Para ello hemos analizado la sensibilización hacia el uso de medidas de seguridad vial en adolescentes en función de tres variables: la vivencia o no de un accidente, la gravedad del mismo y el grado de parentesco. Los resultados obtenidos, en contra de lo esperado, constatan que la sensibilización no está relacionada inequívocamente con ellas, a excepción de los hermanos en cuanto al grado de parentesco y leve en cuanto a la gravedad

The mitochondrial protease HtrA2 restricts the NLRP3 and AIM2 inflammasomes.

Activation of the inflammasome pathway is crucial for effective intracellular host defense. The mitochondrial network plays an important role in inflammasome regulation but the mechanisms linking mitochondrial homeostasis to attenuation of inflammasome activation are not fully understood. Here, we report that the Parkinson\u27s disease-associated mitochondrial serine protease HtrA2 restricts the activation of ASC-dependent NLRP3 and AIM2 inflammasomes, in a protease activity-dependent manner. Consistently, disruption of the protease activity of HtrA2 results in exacerbated NLRP3 and AIM2 inflammasome responses in macrophages ex vivo and systemically in vivo. Mechanistically, we show that the HtrA2 protease activity regulates autophagy and controls the magnitude and duration of inflammasome signaling by preventing prolonged accumulation of the inflammasome adaptor ASC. Our findings identify HtrA2 as a non-redundant mitochondrial quality control effector that keeps NLRP3 and AIM2 inflammasomes in check