908 resultados para Directed Movements
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Recent evidence indicates that dogs' sociocognitive abilities and behaviour in a test situation are shaped by both genetic factors and life experiences. We used the 'unsolvable task' paradigm to investigate the effect of breed and age/experience on the use of human-directed gazing behaviour. Following a genetic classification based on recent genome analyses, dogs were allocated to three breed groups, namely Primitive, Hunting/Herding and Molossoid. Furthermore, we tested dogs at 2 months, 4.5. months and as adults. The test consisted of three solvable trials in which dogs could obtain food by manipulating a plastic container followed by an unsolvable trial in which obtaining the food became impossible. The dogs' behaviour towards the apparatus and the people present was analysed. At 2 months no breed group differences emerged and although human-directed gazing behaviour was observed in approximately half of the pups, it occurred for brief periods, suggesting that the aptitude to use human-directed gazing as a request for obtaining help probably develops at a later date when dogs have had more experience with human communication. Breed group differences, however, did emerge strongly in adult dogs and, although less pronounced, also in 4.5-month-old subjects, with dogs in the Hunting/Herding group showing significantly more human-directed gazing behaviour than dogs in the other two breed groups. These results suggest that, although the domestication process may have shaped the dog's human-directed communicative abilities, the later selection for specific types of work might also have had a significant impact on their emergence. © 2011 The Association for the Study of Animal Behaviour.
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Recently, Cardon and Tuckfield (2011) [1] have described the Jordan canonical form for a class of zero-one matrices, in terms of its associated directed graph. In this paper, we generalize this result to describe the Jordan canonical form of a weighted adjacency matrix A in terms of its weighted directed graph.
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The bulletin is a report of the State Supervisor of Elementary Rural Schools. It includes field work, rural school progress, and recommendations.
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Tese de doutoramento, Engenharia Biomédica e Biofísica, Universidade de Lisboa, Faculdade de Ciências, 2015
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Introdução: O movimento do membro superior está de forma inequívoca direccionado para a resolução de problemas neuromotores. O gesto de alcance constitui o exemplo mais evidente da capacidade deste segmento se organizar no espaço com objetivos específicos e relacionados com a concretização de um propósito motor. A diminuição da necessidade de recorrer a estratégias compensatórias podem ser melhoradas através da implementação de uma intervenção baseada num processo de raciocínio clínico, assente na comprensão dos componentes específicos do movimento e do controle motor, o conceito de Bobath (CB). Objetivo: Pretendeu-se analisar as alterações nas variáveis: deslocamento do tronco, tempo de execução do movimento, unidades de movimento e velocidade máxima da mão no gesto de alcançar em 4 indivíduos com alterações neuromotoras decorrentes de um AVE, face à aplicação de um programa de intervenção baseado no CB. Metodologia: O estudo apresenta quatro casos de indivíduos com AVE, que realizaram intervenção em fisioterapia baseada no CB, durante 12 semanas. Antes e após a intervenção, analisadas as variáveis: deslocamento do tronco, tempo de execução do movimento, unidades de movimento e velocidade máxima da mão no gesto de alcançar recorrendo ao Qualisys Track Manager. Avaliou-se os movimentos compensatórios durante o gesto de alcance, através da Reach Performance Test e a Fugl-Meyer Assessment of Motor Recovery after Stroke para avaliar o comprometimento motor do MS. Resultados: Após a intervenção, os indivíduos em estudo apresentaram, na sua maioria, uma diminuição dos movimentos compensatórios no movimento de alcance. Apresentando diminuição deslocamento do troco, tempo de execução do movimento, unidades de movimento e um aumento na velocidade da mão. Conclusão: A intervenção baseada no CB teve efeitos positivos do ponto de vista do CP do tronco e MS, nos quatro indivíduos com AVE.
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Trabalho de Projeto realizado para obtenção do grau de Mestre em Engenharia Informática e de Computadores
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In recent years, new methods of clean and environmentally friendly energy production have been the focus of intense research efforts. Microbial fuel cells (MFCs) are devices that utilize naturally occurring microorganisms that feed on organic matter, like waste water, while producing electrical energy. The natural habitats of bacteria thriving in microbial fuel cells are usually marine and freshwater sediments. These microorganisms are called dissimilatory metal reducing bacteria (DMRB), but in addition to metals like iron and manganese, they can use organic compounds like DMSO or TMAO, radionuclides and electrodes as terminal electron acceptors in their metabolic pathways.(...)
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This paper studies how shocks in the prices of Food, Energy and Financial Assets affect private consumption using a VAR Model. Then, the total effects are broken into direct and indirect effects, using the coefficients taken from the previous model. We use quarterly data for the Portuguese economy from the last 20 years. We found that energy prices and financial assets have a strong connection with consumption, suggesting that the economy may be too exposed to shocks in these markets.
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Na,K-ATPase is the main active transport system that maintains the large gradients of Na(+) and K(+) across the plasma membrane of animal cells. The crystal structure of a K(+)-occluding conformation of this protein has been recently published, but the movements of its different domains allowing for the cation pumping mechanism are not yet known. The structure of many more conformations is known for the related calcium ATPase SERCA, but the reliability of homology modeling is poor for several domains with low sequence identity, in particular the extracellular loops. To better define the structure of the large fourth extracellular loop between the seventh and eighth transmembrane segments of the alpha subunit, we have studied the formation of a disulfide bond between pairs of cysteine residues introduced by site-directed mutagenesis in the second and the fourth extracellular loop. We found a specific pair of cysteine positions (Y308C and D884C) for which extracellular treatment with an oxidizing agent inhibited the Na,K pump function, which could be rapidly restored by a reducing agent. The formation of the disulfide bond occurred preferentially under the E2-P conformation of Na,K-ATPase, in the absence of extracellular cations. Using recently published crystal structure and a distance constraint reproducing the existence of disulfide bond, we performed an extensive conformational space search using simulated annealing and showed that the Tyr(308) and Asp(884) residues can be in close proximity, and simultaneously, the SYGQ motif of the fourth extracellular loop, known to interact with the extracellular domain of the beta subunit, can be exposed to the exterior of the protein and can easily interact with the beta subunit.
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Résumé Le transfert du phosphate des racines vers les feuilles s'effectue par la voie du xylème. Il a été précédemment démontré que la protéine AtPHO1 était indispensable au transfert du phosphate dans les vaisseaux du xylème des racines chez la plante modèle Arabidopsis thaliana. Le séquençage et l'annotation du génome d'Arabidopsis ont permis d'identifier dix séquences présentant un niveau de similarité significatif avec le gène AtPHO1 et constituant une nouvelle famille de gène appelé la famille de AtPHO1. Basée sur une étude moléculaire et génétique, cette thèse apporte des éléments de réponse pour déterminer le rôle des membres de ia famille de AtPHO1 chez Arabidopsis, inconnue à ce jour. Dans un premier temps, une analyse bioinformatique des séquences protéiques des membres de la famille de AtPHO1 a révélé la présence dans leur région N-terminale d'un domaine nommé SPX. Ce dernier est conservé parmi de nombreuses protéines impliquées dans l'homéostasie du phosphate chez la levure, renforçant ainsi l'hypothèse que les membres de la famille de AtPHO1 auraient comme AtPHO1 un rôle dans l'équilibre du phosphate dans la plante. En parallèle, la localisation tissulaire de l'expression des gènes AtPHO dans Arabidopsis a été identifiée par l'analyse de plantes transgéniques exprimant le gène rapporteur uidA sous le contrôle des promoteurs respectifs des gènes AtPHO. Un profil d'expression de chaque gène AtPHO au cours du développement de la plante a été obtenu. Une expression prédominante au niveau des tissus vasculaires des racines, des feuilles, des tiges et des fleurs a été observée, suggérant que les gènes AtPHO pourraient avoir des fonctions redondantes au niveau du transfert de phosphate dans le cylindre vasculaire de ces différents organes. Toutefois, plusieurs régions promotrices des gènes AtPHO contrôlent également un profil d'expression GUS non-vasculaire, indiquant un rôle putatif des gènes AtPHO dans l'acquisition ou le recyclage de phosphate dans la plante. Dans un deuxième temps, l'analyse de l'expression des gènes AtPHO durant une carence en phosphate a établi que seule l'expression des gènes AtPHO1, AtPHO1; H1 et AtPHO1; H10 est régulée par cette carence. Une étude approfondie de leur expression en réponse à des traitements affectant l'homéostasie du phosphate dans la plante a ensuite démontré leur régulation par différentes voies de signalisation. Ensuite, une analyse détaillée de la régulation de l'expression du gène AtPHO1; H1O dans des feuilles d'Arabidopsis blessées ou déshydratées a révélé que ce gène constitue le premìer gène marqueur d'une nouvelle voie de signalisation induite par l'OPDA, pas par le JA et dépendante de la protéine COI1. Ces résultats démontrent pour la première fois que l'OPDA et le JA peuvent activer différents gènes via des voies de signalisation dépendantes de COI1. Enfin, cette thèse révèle l'identification d'un nouveau rôle de la protéine AtPHO1 dans la régulation de l'action de l'ABA au cours des processus de fermeture stomatique et de germination des graines chez Arabidopsis. Bien que les fonctions exactes des protéines AtPHO restent à être déterminées, ce travail de thèse suggère leur implication dans la propagation de différents signaux dans la plante via la modulation du potentiel membranaire et/ou l'affectation de la composition en ions des cellules comme le font de nombreux transporteurs ou régulateur du transport d'ions. Summary Phosphate is transferred from the roots to the shoot via the xylem. The requirement for AtPHO1 protein to transfer phosphate to the xylem vessels of the root has been previously demonstrated in Arabidopsis thaliana. The sequencing and the annotation of the Arabidopsis genome had allowed the identification of ten sequences that show a significant level of similarity with the AtPHO1 gene. These 10 genes, of unknown functions, constitute a new gene family called the AtPHO1 gene family. Based on a molecular and genetics study, this thesis reveals some information needed to understand the role of the AtPHO1 family members in the plant Arabidopsis. First, a bioinformatics study revealed that the AtPHO sequences contained, in the N-terminal hydrophilic region, a motif called SPX and conserved among multiple proteins involved in phosphate homeostasis in yeast. This finding reinforces the hypothesis that all AtPHO1 family members have, as AtPHO1, a role in phosphate homeostasis. In parallel, we identified the pattern of expression of AtPHO genes in Arabidopsis via analysis of transgenic plants expressing the uidA reporter gene under the control of respective AtPHO promoter regions. The results exhibit a predominant expression of AtPHO genes in vascular tissues of all organs of the plant, implying that these AtPHO genes could have redundant functions in the transfer of phosphate to the vascular cylinder of various organs. The GUS expression pattern for several AtPHO promoter regions was also detected in non-vascular tissue indicating a broad role of AtPHO genes in the acquisition or in the recycling of phosphate in the plant. In a second step, the analysis of the expression of AtPHO genes during phosphate starvation established that only the expression of the AtPHO1, AtPHO1; H1 and AtPHO1; H10 genes were regulated by Pi starvation. Interestingly, different signalling pathways appeared to regulate these three genes during various treatments affecting Pi homeostasis in the plant. The third chapter presents a detailed analysis of the signalling pathways regulating the expression of the AtPHO1; H10 gene in Arabidopsis leaves during wound and dehydrated stresses. Surprisingly, the expression of AtPHO1; H10 was found to be regulated by OPDA (the precursor of JA) but not by JA itself and via the COI1 protein (the central regulator of the JA signalling pathway). These results demonstrated for the first time that OPDA and JA could activate distinct genes via COI1-dependent pathways. Finally, this thesis presents the identification of a novel role of the AtPHO1 protein in the regulation of ABA action in Arabidopsis guard cells and during seed germination. Although the exact role and function of AtPHO1 still need to be determined, these last findings suggest that AtPHO1 and by extension other AtPHO proteins could mediate the propagation of various signals in the plant by modulating the membrane potential and/or by affecting cellular ion composition, as it is the case for many ion transporters or regulators of ion transport.
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In the context of an autologous cell transplantation study, a unilateral biopsy of cortical tissue was surgically performed from the right dorsolateral prefrontal cortex (dlPFC) in two intact adult macaque monkeys (dlPFC lesioned group), together with the implantation of a chronic chamber providing access to the left motor cortex. Three other monkeys were subjected to the same chronic chamber implantation, but without dlPFC biopsy (control group). All monkeys were initially trained to perform sequential manual dexterity tasks, requiring precision grip. The motor performance and the prehension's sequence (temporal order to grasp pellets from different spatial locations) were analysed for each hand. Following the surgery, transient and moderate deficits of manual dexterity per se occurred in both groups, indicating that they were not due to the dlPFC lesion (most likely related to the recording chamber implantation and/or general anaesthesia/medication). In contrast, changes of motor habit were observed for the sequential order of grasping in the two monkeys with dlPFC lesion only. The changes were more prominent in the monkey subjected to the largest lesion, supporting the notion of a specific effect of the dlPFC lesion on the motor habit of the monkeys. These observations are reminiscent of previous studies using conditional tasks with delay that have proposed a specialization of the dlPFC for visuo-spatial working memory, except that this is in a different context of "free-will", non-conditional manual dexterity task, without a component of working memory.