5 resultados para Dupuis, Charles-François, 1742-1809.

em Consorci de Serveis Universitaris de Catalunya (CSUC), Spain


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Methods for the extraction of features from physiological datasets are growing needs as clinical investigations of Alzheimer’s disease (AD) in large and heterogeneous population increase. General tools allowing diagnostic regardless of recording sites, such as different hospitals, are essential and if combined to inexpensive non-invasive methods could critically improve mass screening of subjects with AD. In this study, we applied three state of the art multiway array decomposition (MAD) methods to extract features from electroencephalograms (EEGs) of AD patients obtained from multiple sites. In comparison to MAD, spectral-spatial average filter (SSFs) of control and AD subjects were used as well as a common blind source separation method, algorithm for multiple unknown signal extraction (AMUSE). We trained a feed-forward multilayer perceptron (MLP) to validate and optimize AD classification from two independent databases. Using a third EEG dataset, we demonstrated that features extracted from MAD outperformed features obtained from SSFs AMUSE in terms of root mean squared error (RMSE) and reaching up to 100% of accuracy in test condition. We propose that MAD maybe a useful tool to extract features for AD diagnosis offering great generalization across multi-site databases and opening doors to the discovery of new characterization of the disease.

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Several clinical studies have reported that EEG synchrony is affected by Alzheimer’s disease (AD). In this paper a frequency band analysis of AD EEG signals is presented, with the aim of improving the diagnosis of AD using EEG signals. In this paper, multiple synchrony measures are assessed through statistical tests (Mann–Whitney U test), including correlation, phase synchrony and Granger causality measures. Moreover, linear discriminant analysis (LDA) is conducted with those synchrony measures as features. For the data set at hand, the frequency range (5-6Hz) yields the best accuracy for diagnosing AD, which lies within the classical theta band (4-8Hz). The corresponding classification error is 4.88% for directed transfer function (DTF) Granger causality measure. Interestingly, results show that EEG of AD patients is more synchronous than in healthy subjects within the optimized range 5-6Hz, which is in sharp contrast with the loss of synchrony in AD EEG reported in many earlier studies. This new finding may provide new insights about the neurophysiology of AD. Additional testing on larger AD datasets is required to verify the effectiveness of the proposed approach.

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Does Independent Component Analysis (ICA) denature EEG signals? We applied ICA to two groups of subjects (mild Alzheimer patients and control subjects). The aim of this study was to examine whether or not the ICA method can reduce both group di®erences and within-subject variability. We found that ICA diminished Leave-One- Out root mean square error (RMSE) of validation (from 0.32 to 0.28), indicative of the reduction of group di®erence. More interestingly, ICA reduced the inter-subject variability within each group (¾ = 2:54 in the ± range before ICA, ¾ = 1:56 after, Bartlett p = 0.046 after Bonfer- roni correction). Additionally, we present a method to limit the impact of human error (' 13:8%, with 75.6% inter-cleaner agreement) during ICA cleaning, and reduce human bias. These ¯ndings suggests the novel usefulness of ICA in clinical EEG in Alzheimer's disease for reduction of subject variability.

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Aquest Treball Final de Carrera de la Llicenciatura de Periodisme de la Universitat Abat Oliba CEU té un doble objectiu: a)dur a terme una aproximació teòrico-filosòfica a la proposta cultural de Charles Taylor, i així aprofundir en l'examen dels elements centrals de la seva bibliografia -sobre tot en els pressupòsits antropològics i socials més destacats, així com també en el seu peculiar "ideal d'autenticitat"-; i b)projectar els dits fonaments teòrics en un apartat de naturalesa pràctica, com a forma de concretar la proposta del pensador nord-americà en algun dels fenòmens més interessants de la realitat mediàtica i cultural espanyola. Així, ens vam decidir per un dels programes televisius que més èxit ha tingut al nostre país als darrers temps: Operación Triunfo, donat que en tractar-se d'un concurs vinculat als somnis i a les aspiracions més profundes dels individus que hi participen, té una relació molt més estreta amb l'ideal d'autenticitat. A més, la justificació fonamental d'aquest estudi es basa en el fet que l'aportació filosòfica de Taylor és molt profitosa respecte a la situació cultural actual pels següents dos motius: a) la seva obra presenta una veritable i complerta proposta en positiu, basada en raons i arguments molt clars, que a més porten una esperança de recuperació a la societat occidental; i b) la seva crítica a la Modernitat no és totalment destructiva sinó que més aviat es basa en una comprensió correcta i una recuperació adequada del sentit originari d'algunes de les fonts morals que defineixen la nostra cultura.

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Estudi comparatiu de les dues traduccions catalanes publicades de David Copperfield de Charles Dickens. La primera de Josep Carner feta l’any 1930 però publicada el 1964 i la segona obra deJoan Sellent del 2003. L’anàlisi mostra que ambdues traduccions, excel·lents, reflecteixen una evolució singular i força accelerada del model de llengua que els traductors fan arribar al seu públic, que és reflex de la complexa història de la llengua catalana del segle xx, que encara s’had’escriure.