Aphasia with anatomical isolation of the language area: A reanalysis on the light of modern neuroimaging techniques

Introduction : Goldstein (1948) and Geschwind (1968), based in data derived from anatomical post-mortem studies, postulated that the disconnection of the perisylvian language areas (PSLA) from other cortical areas was responsible for impairments in spontaneous speech and language comprehension with preservation of verbal repetition and echolalia (isolation of speech area). Nevertheless, other mechanisms (right hemisphere or bilateral hypotheses) underlying echolalic repetition have been proposed. Herein, we examined the structure and function of the PSLAs in two cases of aphasia with echolalic repetition and isolation of the left PSLA. Methods : Two patients with chronic post-stroke aphasia associated to isolation of the left PSLA were studied. Both patients underwent cognitive-language assessment and multimodal imaging. In patient 1 (p1), structural MRI, diffusion tensor imaging (DTI), functional MRI (fMRI) during repetition of words and non-words, resting state fMRI (rsfMRI) were acquired, whereas only structural MRI was performed in patient 2 (p2). The Tractotron software was used to examine the severity of disconnection in each language-related white matter tract in both patients. We quantified the severity of the disconnection by measuring the proportion of each tract that was affected. 18FDG-PET was also acquired in both patients. Results : P1 had a mixed transcortical aphasia and p2 had a transcortical sensory/anomic aphasia. In both, the MRI showed separate left anterior and posterior lesions with relative preservation of the PSLA. In both, 18FDG-PET revealed significant decrements of metabolic activity in areas of the left PSLA, although some parts showed normal metabolic activity. In p1 the left arcuate fasciculus (AF) and the inferior fronto-occipital fasciculi (IFOF) could not be reconstructed. fMRI showed perilesional activity in the left hemisphere and increased activity in the right during word repetition. rsfMRI showed compensatory activity in both hemispheres (right greater than left). Analysis with the Tractotron software revealed disconnection of both the AF and the IFOF in the left hemisphere of both patients. Discussion : Although some parts of the left PSLA had preserved metabolic activity in both patients, our neuroimaging data revealed that preserved repetition ability did not rely exclusively on the residual activity of the left PSLA. In support, the connectivity between different components of the left PSLA was severely affected. This coupled with the increased metabolic activity of the right PSLA supports the bilateral hypothesis of residual repetition in transcortical aphasias. References : Goldstein, K. (1948). Language and Language Disturbances. Geschwind, et al. (1968). Neuropsychologia 6, 327–340.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tec

“Need to know” and the right temporal lobe: Impaired access to semantic knowledge in acquired obsessive-compulsive disorder?

Introduction : Idiopathic obsessive-compulsive disorder (I-OCD) has been linked to abnormalities in corticostriatal circuits. Few studies have examined if the same structures are also responsible of acquired OCD (A-OCD) or if damage to anatomically-connected brain regions (e.g., temporal lobes) are also implicated in its pathogenesis. Additionally, there are some discrete obsessive-compulsive (OC) symptoms that by virtue of their presumed low occurrence and difficultly of categorization have received less attention. Amongst these, one intriguing and potentially severe type of obsessive thinking is the so-called “need to know” (NtK), a strong drive to know and obtain given information. In some patients this specific symptom, presumably resulting from impaired access to conceptual knowledge for specific verbal information (proper names, names of places), may be the principal or major feature of OCD symptomatology. We here report the cases of two male patients who developed “NtK” as the only OC symptomatology in association with malignant neoplasms involving the right temporal lobe and connected corticostriatal circuits. Methods : We used Tractotron and Disconnectome map softwares in order to identify the regions of white matter damage overlap across both patients and the proportion of damage (lesion load) of each tract of interest for each patient. We quantified the severity of the disconnection by measuring the proportion of each tract of interest to be affected by each patient´s lesion by using Tractotron software. Additionally, Positron Emission Tomography was used in order to study metabolic abnormalities. The tracts of interest were: the uncinate fasciculus, the anterior commissure, the anterior thalamic radiations, the inferior fronto-occipital fasciculus and the inferior longitudinal fasciculus. Results : There was a high overlap across brain lesions in patients 1 and 2. There was also a high overlap between areas that were affected (disconnected) due to the lesion. As expected, all the a priori selected pathways in the right hemisphere were affected since they cross the anterior part of the temporal lobe. Disconnection maps and metabolic changes in our patients suggest that the expression of OC symptoms underpinned by a semantic deficit due to right temporal damage is secondary to involvement of the uncinate fasciculus linking the temporal pole with the orbitofrontal cortex. Discussion : Data from the present study concur with previous research on A-OCD and current findings in I-OCD which suggest that the temporal lobes participate in the phenomenological expression of OCD. Also, patients with lesions in the anterior temporal lobe are prone to show a specific “Need to Know” symptoms phenomenologically similar to patients with semantic dementia in later stages. The expression of OC symptoms underpinned by a semantic deficit because of anterior right temporal lobe lesion, are due to a disconnection of the uncinate fasciculus and the orbitofrontal cortex. Further research about the neurological underpinnings of specific OCD subtypes, its evaluation and treatment, are essential. References : Berthier ML et al. Neurology. (1996) 47: 353–61. Huey E et al. J Neuropsych Clin Neurosci (2008). 20(4):390-408 Keywords : Emotions & Social Cognition; patients; single case study; adults; psychiatric; lesion mapping, behavioural.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Reviews of Educational Policy regarding one laptop per child: Escuela 2.0 program in Castilla-La Mancha, Spain.

The present study assesses the attitudes and practices of teachers in relation to the national program Escuela 2.0 in Spain, implemented in 2009. The study analyzes attitudes and needs of 424 teachers and it assesses teaching practices developed with Information and Communication Technologies (ICT). Data is analyzed through mixed methods with various instruments using descriptive analysis, factor analysis and a detailed analysis regarding teaching practice from 21 cases. In conclusion, one third of teachers properly integrate Educational Technology into practice. Moreover 62% of teachers support the applied one laptop per child policy and have positive feedback in this regard, however two thirds of the teachers in the sample integrate technology with isolated activities, adapting persisting traditional pedagogical models. There are deficiencies concerning school performance, group work, problem solving and communication in learning activities. Therefore, students need educational guidance for the appropriate use of ICT in the learning process

NUEVA DOCTRINA DEL TRIBUNAL DE JUSTICIA DE LA UNIÓN EUROPEA ACERCA DE LA PROVISIÓN DE ENLACES EN INTERNET (Comentario a la Sentencia del Tribunal de Justicia de la Unión Europea, de 8 de septiembre de 2016, en el asunto C-160/15 [Caso GS Media]). NEW DOCTRINE OF THE COURT OF JUSTICE OF EUROPEAN UNION ABOUT THE PROVISION OF HYPERLINKS IN THE INTERNET

El TJUE dictó el pasado 8 de Septiembre de 2016 una nueva sentencia reiterando su doctrina acerca de los hipervínculos y su consideración como actos de comunicación al público. La novedad de este nuevo pronunciamiento estriba en que el TJUE incorpora una serie de presunciones que descansan sobre el ánimo de lucro o no de la persona que provee el enlace y que determinará, salvo prueba en contrario, que la actividad de enlazar sea considerada un acto de puesta a disposición del público, en el sentido del artículo 3.1 de la Directiva 2001/29, sobre derechos de autor y derechos afines en la sociedad de la información (DASSI), así como el régimen de responsabilidad del proveedor del enlace

LA CONSIDERACIÓN DE LOS ENLACES COMO ACTOS DE COMUNICACIÓN PÚBLICA (Comentario a la Sentencia del Tribunal de Justicia de la Unión Europea de 13 de febrero de 2014 en el asunto C-466/12 [Caso Svensson]).

El TJUE emitió el pasado 13 de febrero de 2014 la sentencia en el asunto Svensson, en la que acepta que el establecimiento de un enlace en Internet sobre los que se puede pulsar y que conduzca a obras protegidas que se encuentran disponibles libremente en otro sitio web supone un acto de puesta a disposición del público, derecho reconocido en el artículo 3.1 de la Directiva 2001/29, sobre derechos de autor y derechos afines en la sociedad de la información (DASSI). El TJUE considera que el facilitar enlaces que conducen a obras protegidas debe calificarse como un acto de puesta a disposición si bien, matiza, es necesario que dicha comunicación se dirija a un público nuevo, esto es, un público que no fue tomado en consideración por los titulares de los derechos de autor cuando autorizaron la comunicación inicial

Use of Optimised LSTM Neural Networks Pre-Trained With Synthetic Data to Estimate PV Generation

Optimising the use of the photovoltaic (PV) energy is essential to reduce fossil fuel emissions by increasing the use of solar power generation. In recent years, research has focused on physical simulations or artifical intelligence models attempting to increase the accuracy of PV generation predictions. The use of simulated data as pre-training for deep learning models has increased in different fields. The reasons are the higher efficiency in the subsequent training with real data and the possibility of not having real data available. This work presents a methodology, based on an deep learning model optimised with specific techniques and pre-trained with synthetic data, to estimate the generation of a PV system. A case study of a photovoltaic installation with 296 PV panels located in northwest Spain is presented. The results show that the model with proper pre-training trains six to seven times faster than a model without pre-training and three to four times faster than a model pre-trained with non-accurate simulated data. In terms of accuracy and considering a homogeneous training process, all models obtained average relative errors around 12%, except the model with incorrect pre-training which performs worse

Análisis del índice de volatilidad VIX, y su relación numérica con información global de mercado

El índice VIX expresa la volatilidad de la bolsa americana S&P 500 en base a una metodología de cálculo que tiene en cuenta principalmente los precios de las opciones que cotizan sobre el S&P 500. Es el índice de volatilidad del mercado americano por excelencia, y el más consultado por los analistas como medidor de la incertidumbre. Este trabajo, partiendo de la premisa del alto grado de globalización de los mercados en el S. XXI, pretende explicar el comportamiento del VIX en base a un conjunto de variables de mercado tales como contravalores de divisas, índices bursátiles, tipos de interés entre otras. Para ello se recurrirá a técnicas estadísticas de análisis multivariante que procuren un modelo predictivo para el índice VIX. Es objeto del trabajo también, la implementación de un mecanismo que ejecute una estrategia de negociación de instrumentos financieros que coticen sobre el VIX, valiéndose de la información proporcionada por el modelo predictivo

Predicting web server crashes: a case study in comparing prediction algorithms

Traditionally, performance has been the most important metrics when evaluating a system. However, in the last decades industry and academia have been paying increasing attention to another metric to evaluate servers: availability. A web server may serve many users when running, but if it is out of service too much time, it becomes useless and expensive. The industry has adopted several techniques to improve system availability, yet crashes still happen. In this paper, we propose a new framework to predict time-to-failure when the system is suffering transient failures that consume resources randomly. We study which machine learning algorithms build a more accurate model of the behavior of the anomaly system, and focus on Linear Regression and Decision Tree algorithms. Our preliminary results show that M5P (a Decision Tree algorithm) is the best option to model the behavior of the system under the random injection of memory leaks.Postprint (published version

Efeitos do solo e clima numa vinha de uva de mesa com cultura de cobertura. Gestão da rega utilizando redes de sensores

[ENG] TThe use of mulches in vineyards and orchards is a traditional agricultural practice used with the aim of saving moisture, reducing weed growth and improving organic matter content in the soil. In table grape vineyards trained to overhead system in Puglia region (Southeastern Italy), plastic sheets covering the canopy are often used to either advance ripening or delay harvest. In this environment, the living mulches could contribute to the modification of the microclimate around the canopy below the plastic sheets. This condition has an influence on the climatic demand and on both the vegetative and productive activities, mainly in stages with a high evapotranspiration. However, the presence of living mulches could increase the demand of available water and nutrient resources and this could cause a lower yield. The aim of this study was to acquire a suitable knowledge to manage irrigation and verify the influences of living mulches on the vine by using wireless sensor networks to measure the vapor pressure deficit, soil water potential and content.[POR] A utilização de coberturas do solo em vinhas e pomares é uma prática agrícola tradicional, utilizada com o objetivo de preservar a humidade do solo, reduzir o crescimento de infestantes e melhorar o teor de matéria orgânica no solo. Em vinhas de uva de mesa, conduzidas em sistema de pérgula na região de Puglia (sudeste da Itália), são frequentemente usadas coberturas de plástico para promover o avanço da maturação ou o atraso da colheita. Neste ambiente a utilização de enrelvamentos pode contribuir para a modificação do microclima do copado. Esta condição pode influenciar a demanda atmosférica, bem como a atividade vegetativa e reprodutiva da videira, principalmente em períodos de elevada evapotranspiração. No entanto, a presença do enrelvamento pode originar um aumento da demanda dos recursos disponíveis, nomeadamente água e nutrientes, o que poderá provocar uma quebra de produção. O objetivo deste estudo foi adquirir conhecimento para a gestão da rega e, simultaneamente, verificar a influência dos enrelvamentos na atividade da videira, usando para o efeito redes de sensores “sem fio” para medir o déficit de pressão de vapor, o potencial e o conteúdo de água no solo.The development of this work was supported by: The Spanish Ministry of Science and Innovation through the project RIDEFRUT (ref. AGL2013-49047-C2-1-R), the “Fundacion Seneca, Agencia de Ciencia y Tecnologia” of the Region of Murcia under the “Excelence Group Program”, and the Technical University of Cartagena under the PMPDI Program