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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1051

O efeito do atraso em movimentos reversos do cotovelos : comparação entre sujeitos saudaveis e portadores da doença de Parkinson / The effect of delay on the control of reversal movements of the elbow: comparison between healthy individuals and Parkinson's disease patients

Santos, Marcus Vinicius Rezende dos 28 February 2005 (has links)
Orientador: Gil Lucio Almeida / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-06T21:23:30Z (GMT). No. of bitstreams: 1 Santos_MarcusViniciusRezendedos_M.pdf: 2514721 bytes, checksum: a7b1ab66caadf0d4fb9a3367038033d5 (MD5) Previous issue date: 2005 / Resumo: Neste trabalho, foram investigados efeitos de condições especiais como o envelhecimento e a Doença de Parkinson no controle de movimentos reversos do cotovelo, realizados com um atraso variável entre a ida (Ml) e a volta (M2) do mesmo. Outro objetivo foi verificar se o ciclo de alongamento-encurtamento (CAE) age como potencializador da contração muscular nessa população. Foram recrutados 12 voluntários, sendo seis sujeitos saudáveis (três homens e três mulheres) com idades entre 51 e 71 anos (Média = 62.33 e DP = 8.95) e seis portadores da doença de Parkinson (três homens e três mulheres) com idades entre 59 e 77 anos (Média = 68.66 e DP = 7.47). Eles realizaram movimentos uni-articulares rápidos de reversão com o cotovelo, que se movia em direção à um alvo (Ml) e depois retomava à posição inicial (M2). Esses movimentos foram realizados em três diferentes distâncias (20°, 40° e 60°) e entre os dois componentes (Ml e M2) foi realizado um atraso variável (Os, 0.2s, 0.5s e ls). O deslocamento angular do cotovelo foi registrado por um sistema óptico de análise do movimento (OPTOTRAK@ 3020) e a atividade elétrica dos músculos braquiorradial (BRR) e cabeça lateral do tríceps braquial (TR) foi registrada através de um eletromiógrafo EMG DelSYS (modelo DE2.2L) com eletrodos de superficie. O envelhecimento saudável não influenciou os padrões EMG utilizados por esses indivíduos para ativar os músculos agonista e antagonista na realização de movimentos uni-articulares com reversão com diferentes atrasos. A velocidade dos movimentos executados por esses indivíduos foi mais baixa devido ao uso de um padrão semelhante aos sujeitos jovens, porém com uma menor quantidade de ativação. Os parkinsonianos moveram mais lentamente que os idosos saudáveis e indivíduos saudáveis devido a algumas alterações na modulação da atividade EMG. Apesar de apresentarem a manutenção do padrão trifásico, a atividade elétrica dos músculos ocorreu na forma de vários bursts altemantes durante toda a realização da tarefa, o que provocou uma redução na quantidade de ativida elétrica dos músculos. Os parkinsonianos não reduziram a magnitude do segundo burst agoninos movimentos sem atraso, o que trouxe uma dificuldade maior para reverter os moviment< Por fim, notou-se que os indivíduos portadores da doença de Parkinson relaxavam menos a SI musculatura e iniciavam o retomo à posição inicial necessitando de uma atividade maior do 1 para gerar uma velocidade igual à dos indivíduos saudáveis, o que não aconteceu. ( movimentos que reverteram sem atraso apresentaram um valor maior da velocidade movimento de retomo à posição inicial, mesmo nos portadores da doença de Parkinso confirmando a ação potencializadora do ciclo de alongamento-encurtamento (CAE) sobre músculo tríceps. Isso suporta a influência, tanto dos reflexos (gerados pelo estiramento muscula quanto da energia potencial armazenada pelo músculo e tendão, que têm suas origens na fa: excêntrica do CAE e são liberados no movimento de volta (fase concêntrica). Palavras-chave: Movimentos reversos, doença de Parkinson, ciclo de alongamento encurtamento, eletromiografia e cinemática / Abstract: Within this study were investigated the effects of special conditions like aging and the Parkinson's disease on the control ofreversal movements ofthe elbow joint performed with a variable delay between the two components (Ml and M2) ofreversal. Another aim was to verify if the stretch-shortening cycle exerts his potentiating effects on muscular contraction in this population. To perform these observations, 12 volunteers were recruited. Six of them (3 males and 3 females) were normal at their neurological assessment and were between 51 and 71 years of age (Mean = 62.33 e S.D.= 8.95), and the other six (3 males and 3 females) had been diagnosised with Parkinson disease and were between 59 and 77 years old (Mean = 68.66 e S.D. = 7.47). They executed fast single-joint movements with a reversal, moving towards a target (Ml) and getting back to the initial position (M2). These movements were accomplished in three different distances (20°, 40° and 60°) and between the two components ofreversal (Ml e M2) there were variable delays (Os, 0.2s, 0.5s eIs). The elbow angle was recorded using a optoelectric system of motion analysis (OPTOTRAK@ 3020) and the electrical activity of braquioradialis (BRR) and lateral head of triceps brachi (TR) muscles were recorded by a electromyograph EMG DelSYS (model DE2.2L) with surface electrodes placed over the muscles bellies. The aging did not affect the EMG patterns used by these persons in activating the agonist and antagonist muscles to accomplish single-joint movements with a delay between the movements toward the target and the return to the initial position. The velocity of movements executed by the elder1y volunteers was lower due to the fact that the same strategy applied to young hea1thy persons was used, however with less EMG activity. The volunteers with Parkinson's disease moved slower than the heaIthy elderly and young subjects due to aIterations in the modulation of EMG activity. Altough they kept the triphasic pattern, the EMG showed multiple bursts that aItemated during the task accomplishmen~ which decreased the amount of ellectricaI activity. Besides, they did not reduce the magnitude of second agonist burst in the reversaI movements without delay, what made the reversion harder. FinaIly, it was noticed that the parkinsonians showed less relaxation of his muscles during the intervaI between TI-T4, and started the return movement needing more TR activity to produce the same velocity, when compared to heaIthy persons, which was not the case. Those movements that reverted with no delay showed higher values concerning the second peak ofvelocity, even within the volunteers with Parkinson disease, sustaining the potentianting action of SSC over the triceps muscle. This effect comes from the influence of reflexes (generated by the muscle stretching), as well as the storage of elastic energy in the muscle and tendon in the eccentric phase of SSC, which are released at the movement of returning (concentric phase) / Mestrado / Fisiologia / Mestre em Biologia Funcional e Molecular
1052

Determinação de elementos essenciais em vinhos por Análise por Ativação com Nêutrons / Determination of essential trace elements in wine by Neutron Activation Analysis

DANIELE, ANNA P. 10 March 2017 (has links)
Submitted by Maria Eneide de Souza Araujo (mearaujo@ipen.br) on 2017-03-10T12:19:37Z No. of bitstreams: 1 22065.pdf: 2518783 bytes, checksum: e0f2e9eb82a52ecd6b57db50dcdac3fb (MD5) / Made available in DSpace on 2017-03-10T12:19:37Z (GMT). No. of bitstreams: 1 22065.pdf: 2518783 bytes, checksum: e0f2e9eb82a52ecd6b57db50dcdac3fb (MD5) / Muitos estudos têm sido realizados para determinar elementos essenciais nos alimentos, dentre eles o vinho, devido aos seus importantes papéis nutricionais em funções do corpo humano. Estudos apontam que o consumo diário e moderado de vinho contribui de forma significativa para as necessidades dos elementos essenciais para o corpo humano, tais como Ca, Co, Cr, Fe, K, Mg, Mn, Zn, V, entre outros, bem como traz benefícios para a saúde como a prevenção de inúmeras doenças e maior expectativa de vida, relacionados em particular com a ingestão de antioxidantes como os compostos polifenólicos. Por outro lado, outros elementos são bons indicadores da origem do vinho e as suas concentrações podem ser utilizadas como critério para garantir a autenticidade e a qualidade do vinho, bem como avaliar se os limites de tolerância estabelecidos pela lei foram respeitados durante todo o processo de produção. Todavia, embora a indústria do vinho no Brasil esteja entre as 15 maiores do mundo, ainda são poucos os estudos analíticos dos elementos no vinho se comparado a outros grandes produtores. Neste sentido este estudo teve como objetivo avaliar alguns procedimentos para preparação de amostras de vinho para determinar elementos essenciais por Análise por Ativação Neutrônica Instrumental (INAA) e comparar os resultados com a técnica de Espectrometria de Emissão Atômica por Plasma de Argônio Acoplado Indutivamente (ICP OES). Três procedimentos de preparação da amostra foram estudados: liofilização, evaporação e calcinação. Os parâmetros estudados foram precisão, exatidão e limite de detecção. Foram aplicados testes estatísticos de ANOVA e Tukey Kramer para verificar as diferenças estatísticas entre as médias obtidas pelos três procedimentos de preparação do vinho para INAA com as médias obtidas por ICP OES. Foi observado que cerca de 60% dos resultados obtidos por liofilização foram concordantes com aqueles obtidos por ICP OES. / Dissertação (Mestrado em Tecnologia Nuclear) / IPEN/D / Instituto de Pesquisas Energéticas e Nucleares - IPEN-CNEN/SP
1053

Estudo e implementação de um método de cinemática inversa baseado em busca heurística para robôs manipuladores = aplicação em robôs redundantes e controle servo visual / Heuristic search based inverse kinematics for robotic manipulators : application to redundant robots and visual servoing

Nicolato, Fabricio 06 January 2007 (has links)
Orientador: Marconi Kolm Madrid / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e de Computação / Made available in DSpace on 2018-08-15T23:54:05Z (GMT). No. of bitstreams: 1 Nicolato_Fabricio_D.pdf: 1516280 bytes, checksum: 96229803f3bca54f669d4dcc22108c02 (MD5) Previous issue date: 2007 / Resumo: Esta tese trata o problema da resolução do modelo cinemático inverso para manipuladores industriais redundantes ou não. O problema foi abordado por um método de busca heurística no qual a solução da cinemática inversa é construída passo a passo calculando-se a contribuição do movimento de apenas uma junta a cada iteração. Dessa forma, o problema n-dimensional é transformado em problemas unidimensionais mais simples, cuja solução analítica tanto para juntas rotacionais quanto para juntas prismáticas é apresentada em termos da representação de Denavit-Hartenberg. O método proposto não possui singularidades internas. Além disso, o método foi expandido para incorporar informações de sensores externos visando fazer com que o processo seja mais robusto a incertezas nas modelagens envolvidas. Foram realizadas diversas simulações e comparações com técnicas tradicionais que evidenciaram as vantagens da abordagem proposta. O trabalho também englobou o projeto e a construção de um ambiente experimental e a implementação das técnicas desenvolvidas na parte teórica. Desenvolveu-se um sistema com um robô planar redundante de 3 DOF, assim como seus sistemas de controle, acionamento e interfaceamento usando técnicas de sistemas hardware-inthe-loop e lógica programável. As técnicas desenvolvidas foram aplicadas no ambiente experimental demonstrando características como: facilidade de lidar com redundâncias, capacidade de resolução em tempo real, robustez a incertezas de parâmetros etc / Abstract: This thesis deals with the problem of solving the inverse kinematics model of redundant and nonredundant industrial manipulators. The work was developed in a theoretical and a practical part. The problem was approached by an heuristic search method in which the solution of the inverse kinematics is built step by step calculating the movement contribution of just a single joint for each iteration. In that way, the n-dimensional problem is transformed in simpler one-dimensional problems, whose analytic solution for both rotational joints and prismatic joints is presented in terms of the Denavit and Hartenberg representation. The proposed method does not possess internal singularities. Furthermore, the method was expanded to incorporate information of external sensor in order to make the process more robust to uncertainties in the involved modelings. Several results of simulations and comparisons with traditional techniques, which evidence the advantages of the proposed approach, are presented. The work also included the construction of an experimental environment and the implementation of the techniques developed in the theoretical part. The details of a system with a 3-DOF redundant robot as well as its control system, drivers and interfaces using hardware-in-theloop techniques and programmable logic are presented. The developed techniques were applied in the experimental environment are demonstrating their efficiency and evidencing characteristics like: easiness of dealing with redundancies, real time capacity, robustness for parameters uncertainties etc / Doutorado / Automação
1054

Correlações entre parâmetros cinemáticos da locomoção terrestre e energética em Cebus apella (macaco-prego) / Correlations between kinematic parameters of terrestrial locomotion and energetics in Cebus apella (capuchin monkey)

Marcel Cintra Pereira Ribeiro 08 December 2006 (has links)
O presente estudo teve como objetivo avaliar o custo energético e alguns aspectos da biomecânica associados à locomoção em Cebus apella (macaco-prego). Para tanto, medidas de taxa metabólica (consumo de oxigênio) e de parâmetros cinemáticos (freqüência de passos, tempo de contato das patas com o plano de apoio, comprimento dos passos e amplitudes de flexão e extensão de juntas e segmentos corpóreos) foram obtidas com os sujeitos experimentais se locomovendo sobre esteira rolante. Nossos resultados mostram que apesar da espécie estudada exibir freqüência de passos inferior ao esperado para mamíferos quadrúpedes de massa corpórea similar, esse parâmetro cinemático é o elemento preferencial do padrão de locomoção que é ajustado para que o animal possa suportar as novas condições do meio (alteração de velocidade). Em adição, os dados de consumo de oxigênio obtidos neste estudo indicam que diferenças significativas não devem ser esperadas entre o custo energético da locomoção de quadrúpedes primatas e não primatas. Sendo assim, foi possível inferir que um outro elemento, além da taxa de geração de força (inferida a partir da freqüência de passos), pode responder pela magnitude do custo energético da locomoção em primatas. Nossas inferências sugerem que características anatômicas de primatas (maior volume muscular associado aos membros posteriores) podem constituir-se no elemento central para o entendimento do custo metabólico exibido pela espécie estudada (similar a quadrúpedes não primatas). Por fim, deve ser salientado que nossos dados indicam que a flexão da coluna pode ser um importante mecanismo para armazenamento de energia (energia elástica) durante a locomoção em Cebus apella, sobretudo em velocidades mais altas. / This study aimed to evaluate the energy expenditure and biomechanical aspects associated to the locomotion of Cebus apella (capuchin monkey). Measurements of metabolic rate (oxygen consumption) and kinematic parameters (stride frequency, foot contact time, step length and degree of flexion-extension of the joints and body segments) were obtained with the experimental subjects moving on a motorized treadmill. Our results show that although the species studied displays a lower stride frequency than quadruped mammals with similar body masses, this is the kinematic parameter that is preferentially adjusted by the animal to cope with faster velocities. In addition, oxygen consumption data obtained in this study indicate that significant differences between the energy cost of locomotion of primates and nonprimates quadrupeds should not be expected. Based on this result, we suggest that another element besides the rate of generating force (inferred from the stride frequency) could explain the energy cost of locomotion in primates. We suggest that anatomic characteristics of primates (larger muscular volume associated with the hind limbs) might be a key element to understand the cost of locomotion showed by capuchin monkeys (similar to non-primate quadrupeds). Our results also indicate that flexion of the column can be an important mechanism for elastic energy storage during locomotion in Cebus apella particularly at higher velocities.
1055

Développement et validation d’une méthode d’évaluation destranslations glénohumérales 3d sous EOS(mc) / Development and validation of a method for evaluating 3dglenohumeral translations with eos™

Lagacé, Pierre-yves 17 December 2012 (has links)
L'analyse morpho-fonctionnelle précise de l'épaule, notamment au niveau de l'articulation glénohumérale (GH), permettrait d'améliorer notre compréhension des dysfonctions de l'épaule associées aux ruptures de la coiffe des rotateurs. Cependant, des difficultés techniques compliquent l'analyse de la morphologie et du mouvement de l'épaule dans un contexte clinique. Dans le cadre de la présente thèse, une méthode d'analyse 3D des translations GH basée sur l'acquisition de séquences de radiographies biplanes sous EOS™ a été développée. Une étude pilote sur 10 sujets sains a d'abord permis de vérifier la facilité d'application d'un protocole d'acquisition des images et d'évaluer la répétabilité de l'identification des repères anatomiques de l'épaule sur les radiographies. La méthode proposée en dernier lieu permet, suite à l'acquisition de radiographies, de reconstruire un modèle personnalisé morpho-réaliste de la scapula et un modèle simplifié de l'humérus. Ces modèles sont ensuite recalés interactivement sur les images acquises à différentes positions du bras et utilisés pour décrire les translations GH à ces positions. La méthode a été validée en termes de précision et de répétabilité sur des images acquises d'épaules cadavériques et de patients ayant des ruptures de la coiffe des rotateurs. La dernière partie du travail présenté ici consiste à appliquer la méthode développée à 30 sujets (25 patients et 5 sujets sains) pour lesquels l'état de la coiffe des rotateurs et la fonction de l'épaule ont été évalués, puis à étudier les corrélations entre les translations GH et la fonction de l'épaule. / Precise morpho-functional analysis of the shoulder, including of the glenohumeral (GH) joint, would allow improving our understanding of shoulder dysfunction associated to rotator cuff tears. However, technical difficulties make analysis of shoulder morphology and motion difficult in a clinical setting. The work carried out during this thesis allowed developing a method for 3D analysis of GH translations relying on the acquisition of sequences of biplanar radiographs with the EOS™ system. A pilot study carried out on 10 healthy subjects allowed verifying the ease of application of an image acquisition protocol and evaluating the repeatability of shoulder landmark identification on the radiographs. The final proposed method allows, following the acquisition of radiographs, obtaining a personalized morphologically realistic reconstruction of the scapula and a simplified model of the humerus. These models are then interactively registered to the images acquired at different arm positions and used to describe GH translations for these positions. The proposed method was validated in terms of precision and repeatability on images acquired of cadaveric shoulders and of patients with rotator cuff tears. The last part of the work presented here consists in applying the developed method to 30 subjects (25 patients and 5 asymptomatic subjects) for whom rotator cuff condition and shoulder function were assessed, and to study correlations between GH translations and shoulder function.
1056

Gait kinematic analysis of the osteoarthritic knee : pre- and post- total knee arthroplasty / Analyse cinématique de la marche chez des patients souffrant d'arthrose du genou : pré et post-arthroplastie totale du genou

Bytyqi, Dafina 25 February 2015 (has links)
Le but de cette thèse était d'étudier, in vivo, la cinématique en 3D du genou lors de la marche sur des patients souffrant d'arthrose du genou et de quantifier l'apport de l'arthroplastie totale du genou (PTG) sur la restauration d'une cinématique normale. Trente patients et un groupe de contrôle composé de 12 participants du même âge ont été inclus dans la première étude. Sur ces 30 patients, nous avons obtenu des évaluations de suivi après l'arthroplastie totale du genou sur 20 patients, avec un délai moyen de 11 mois. L'analyse cinématique tridimensionnelle du genou a été réalisée en utilisant le système KneeKGTM. Cette analyse de la marche a révélé que la cinématique de genou avec arthrose médiale diffère de la cinématique du genou sain. Le groupe avec arthrose du genou montrait une stratégie de raidissement de la marche en présentant une réduction de mouvement non seulement dans le plan sagittal, mais aussi dans le plan axial. Après PTG, les patients avaient de meilleurs paramètres cliniques, spatio-temporels et cinématiques. Malgré les améliorations, la cinématique du genou lors de la marche dans le groupe PTG différaient de celle du groupe contrôle / Patients with knee osteoarthritis tend to modify spatial and temporal parameters during walking to reduce the pain. There are common gait features which are consistently shown to be significantly linked to osteoarthritis severity such as knee adduction moment, knee flexion angle, stiffness and walking speed. Total knee arthroplasty (TKA) is considered the gold standard treatment for end-stage knee osteoarthritis. Nearly a million of total knee prosthesis are implanted worldwide each year. However, reduced physical function of the knee is partly, but apparently not fully, remedied by surgery. The purpose of this thesis was to investigate the in vivo, three dimensional knee kinematics during gait at the patients with knee osteoarthritis and the influence of total knee arthroplasty on restoration of normal kinematics. Weight bearing kinematics in medial OA knees differ from normal knee kinematics. Knee OA group showed an altered “screw-home” mechanism by decreased excursion in sagittal and axial tibial rotation and a posterior translation of the tibia. Following TKA, patients had better clinical, spatiotemporal and kinametic parameters. They walked longer, faster and with a better range of motion. Despite improvements, the knee kinematics during gait in TKA group differed from healthy control group. They had a lower extension, lower range of axial rotation and an increased tibial posterior translation. Future research should be focused on comparing different designs of prosthesis pre- and post operatively in a longer follow-up delay
1057

A distribuição e cinemática do gás em mrk766 vistas em detalhes a partir de observações no infravermelho / The kinematics and the flux distribution in mrk766 seen in details from infrared observations

Schönell Júnior, Astor João 22 February 2013 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / We have mapped emission-line flux distributions and ratios as well as the gaseous kinematics of the inner 450 pc radius of the Seyfert galaxy Mrk 766 using integral field near-IR J- and Kl-band spectra obtained with the Gemini North instrument NIFS at a spatial resolution of ≈60 pc and velocity resolution of ≈40 kms−1. Emission-line flux distributions in Pa β and Brγ extend to ≈300 pc from the nucleus in all directions, while the [Fe II] emission is extended to a similar distance but mostly along PA≈130◦. The coronal lines traced by [S IX] are resolved, presenting emission up to ≈150 pc from the nucleus. The molecular H2 gas emission is extended also to ≈300 pc from the nucleus but along PA≈50º, approximately perpendicularly to the orientation of the [Fe II] emission. The H2 gas has an excitation temperature Texc = 2360±45K and its emission is dominated by thermal processes, mainly due X-ray heating by the active nucleus. The [Fe II] emission seems also to be produced by these thermal processes, but with an important contribution from shocks, as evidenced by the correlation between enhanced [Fe II]/[P II] line ratios, the [Fe II] velocity dispersion and the radio structure. The gas velocity field is dominated by rotation, and the fit of a circular model gives a position angle of 59º for the line of nodes, which is the approximate orientation of the extended H2 emission. This fact, combined with the low H2 velocity dispersion close to the velocity resolution of the data supports a location of the H2 emitting gas in the galaxy plane, and its association with the feeding of the supermassive black hole. There is about 103 M⊙ of hot H2, implying ≈109 M⊙ of cold molecular gas in the inner 450 pc radius. On the other hand, the higher velocity dispersion (150 kms−1) for [Fe II] to the southeast of the nucleus, and the presence of both blueshifts and redshifts in the channel maps at the corresponding locations, supports the presence of an outflow to the southwest with an axis lying close to the plane of the sky. The ionized gas outflow rate is estimated to be 2.18 M⊙ yr−1, and the power of the outflow 0.011 Lbol. The distinct flux distributions and kinematics of the H2 and [Fe II] emitting gas, with the first more restricted to the plane of the galaxy and in rotation and the second related with the radio jet and in outflow are common characteristics of 8 Seyfert galaxies (ESO428-G14, NGC4051, NGC7582, NGC4151, Mrk 1066, Mrk 1157, Mrk 79 and Mrk 766) we have studied so far using similar integral-field observations and 2 others (Circinus and NGC2110) using long-slit observations. These results support the conclusion that the H2 emission is tracer of the AGN feeding, while the [Fe II] is a tracer of its feedback. / Mapeamos as distribuições de fluxos de linhas de emissão e suas razões bem como a cinemática do gás nos 450 pc centrais da galáxia Seyfert Mrk 766 usando espectroscopia de campo integral (IFS) na região do infravermelho próximo nas bandas J e Kl obtidas com o instrumento NIFS do telestcópio Gemini-Norte com uma resolução espacial de ≈ 60 pc e resolução espectral de ≈ 40 km s−1. As distribuições de fluxos das linhas de emissão de Paβ e Brγ se estendem até ≈ 300 pc do núcleo em todas as direções, enquanto a emissão do [Fe II] se estende até uma distância similar, porém, mais concentrada ao longo do PA≈ 130º. As linhas coronais traçadas pelo [S IX] são resolvidas, apresentando emissão até ≈ 150 pc do núcleo. A emissão do H2 molecular é estendida também a ≈ 300 pc do núcleo, mas, ao longo do PA ≈ 50º, aproximadamente perpendicular a orientação da emissão do [Fe II]. O gás H2 tem uma temperatura de excitação Texc = 2360 ±45 K e sua emissão é dominada por processos térmicos, principalmente devido a aquecimento do gás por raios-X provenientes do núcleo ativo. A emissão do [Fe II] também parece ser produzida por esses processos térmicos, mas com uma importante contribuição dos choques, assim como evidenciado pela razão [Fe II]/[P II] e por aumentos na dispersão de velocidades associados com o jato rádio. e a estrutura rádio. O campo de velocidades do gás é dominado por rotação, e o ajuste de um modelo de órbitas circulares no plano da galáxia nos dá um ângulo de posição de 59º para a linha dos nodos, o que parece ser aproximadamente a orientação da elongação da emissão do H2. Este fato, combinado com a baixa dispersão de velocidades do H2 é consistente com emissão de gás localizado no plano da galáxia e sua associação com a alimentação do buraco negro supermassivo. Há aproximadamente 103 M⊙ de H2 quente, implicando em ≈ 109 M⊙ de gás molecular frio no interior dos 450 pc centrais. Por outro lado, a maior dispersão de velocidades para o [Fe II] (150 km s−1) a sudeste do núcleo, e a presença tanto de blueshifts quanto redshifts nos mapas de fluxo para diferentes velocidades nas correspondentes localizações, apoiam a presença de um outflow a sudeste, orientado próximo ao plano do céu. A taxa de outflow de gás ionizado é estimada em 2.18 M⊙ ano−1 e sua potência em 0.011 Lbol. As distintas distribuições de fluxo e cinemática do H2 e do [Fe II], com o primeiro mais restrito ao plano da galáxia e em rotação e o segundo relacionado com o jato rádio e em outflow são características comuns de 8 galáxias Seyferts (ESO 428-G14, NGC4051, NGC 7582, NGC 4151, Mrk 1066, Mrk 1157, Mrk 79 e Mrk 766) que foram estudadas por nosso grupo até agora, usando IFS e 2 outras (Circinus e NGC 2110) usando esoectroscopia de fenda longa. Estes resultados apoiam a conclusão de que a emissão do H2 é um traçador da alimentação do núcleo ativo, enquanto o [Fe II] é um traçador de seu feedback.
1058

IN-SYNC. V. Stellar Kinematics and Dynamics in the Orion A Molecular Cloud

Da Rio, Nicola, Tan, Jonathan C., Covey, Kevin R., Cottaar, Michiel, Foster, Jonathan B., Cullen, Nicholas C., Tobin, John, Kim, Jinyoung S., Meyer, Michael R., Nidever, David L., Stassun, Keivan G., Chojnowski, S. Drew, Flaherty, Kevin M., Majewski, Steven R., Skrutskie, Michael F., Zasowski, Gail, Pan, Kaike 16 August 2017 (has links)
The kinematics and dynamics of young stellar populations enable us to test theories of star formation. With this aim, we continue our analysis of the SDSS-III/APOGEE IN-SYNC survey, a high-resolution near-infrared spectroscopic survey of young clusters. We focus on the Orion A star-forming region, for which IN-SYNC obtained spectra of similar to 2700 stars. In Paper IV we used these data to study the young stellar population. Here we study the kinematic properties through radial velocities (vr). The young stellar population remains kinematically associated with the molecular gas, following a similar to 10 km s(-1) gradient along the filament. However, near the center of the region, the vr distribution is slightly blueshifted and asymmetric; we suggest that this population, which is older, is slightly in the foreground. We find evidence for kinematic subclustering, detecting statistically significant groupings of colocated stars with coherent motions. These are mostly in the lower-density regions of the cloud, while the ONC radial velocities are smoothly distributed, consistent with it being an older, more dynamically evolved cluster. The velocity dispersion sigma(v) varies along the filament. The ONC appears virialized, or just slightly supervirial, consistent with an old dynamical age. Here there is also some evidence for ongoing expansion, from a v(r)-extinction correlation. In the southern filament, sigma(v) is similar to 2-3 times larger than virial in the L1641N region, where we infer a superposition along the line of sight of stellar subpopulations, detached from the gas. In contrast, sv decreases toward L1641S, where the population is again in agreement with a virial state.
1059

Near-infrared proper motion surveys

Smith, Leigh Charles January 2016 (has links)
I present the development of two near infrared proper motion pipelines for high resolution near infrared data from UKIDSS and the VISTA VVV survey. The UKIDSS pipeline is capable of accuracies of order 5-10 mas yr⁻¹ for bright sources with the largest epoch baselines (~ 8 years). The VVV pipeline reaches 1-2 mas yr⁻¹ proper motion precision at the bright end and parallax measurements at ~ 1 mas precision. It will be possible to improve upon the VVV astrometric precision due to increases in data volume and further pipeline development. I have used the proper motion pipelines to generate three near infrared proper motion catalogues of the UKIDSS LAS and GPS and the VVV survey. The LAS proper motion catalogue covers 1500 deg2 at high Galactic latitudes and contains approximately 15 million sources with two J band epochs. The GPS proper motion catalogue covers 1500 deg2 of the northern Galactic plane and contains approximately 400 million sources with two K band epochs. The VVV proper motion catalogue covers 560 deg2 of the Galactic bulge and disc and contains approximately 200 million sources with between 50 and 150 Ks band epochs. I have also produced a preliminary 5σ parallax catalogue containing 3403 VVV sources. The LAS and GPS proper motion catalogues have been used by myself and other authors to identify and study many new examples of high proper motion stars, brown dwarfs, ul-tracool dwarf benchmark candidates, cool white dwarfs, substellar subdwarfs and nearby sources within < 25 pc. These catalogues remain far from fully exploited and will be a useful resource for future research by the astronomical community. Exploitation of the VVV proper motion catalogue is still in its infancy, yet it has already generated large numbers of new high proper motion sources. These include new brown dwarf candi-dates, important benchmark objects, and nearby sources which have previously avoided detection. Parallax results from the VVV pipeline will be useful to improve low mass star/ultracool dwarf luminosity functions, significantly increasing the numbers of brown dwarfs with known parallaxes and illustrates how general purpose multi-epoch wide area surveys can generate parallaxes. Finally, I discuss the long term usefulness of such catalogues in the Gaia era and how they might be exploited in the future.
1060

Quantification des mouvements de la mimique faciale par motion capture sur une population de volontaires sains / Quantification of facial movements by motion capture on healthy volunteers

Sarhan, François-Régis 14 June 2017 (has links)
La prise en charge des déficits moteurs de la mimique faciale est complexe et nécessite un suivi sur le long terme. Il existe de nombreuses techniques d’évaluation de la mimique faciale déficitaire avec des degrés variables de sensibilité. Cependant, la plupart de ces techniques sont manuelles et qualitatives (testing musculaire et scores cliniques). Elles conduisent donc à des mesures subjectives et peu reproductibles dans le temps. Ces techniques d’évaluation reposent en outre sur l’appréciation de l’évaluateur qui est une source importante de biais. Ainsi, l’apport d’un outil de mesure objectif pour quantifier un déficit et optimiser le suivi et la prise en charge médicale, chirurgicale et rééducative des patients apparait comme nécessaire. L’objectif de ce travail de thèse était donc de développer un outil quantitatif permettant d’évaluer les troubles de la mimique faciale. Dans cette perspective, nous avons mis en place un protocole d’analyse du mouvement par motion capture et avons réalisé des mesures sur une population de référence. Une étude descriptive utilisant un système de capture de mouvement en 3 dimensions a été réalisée sur des volontaires sains (n = 30) âgés de 20 à 30 ans. Le système de capture du mouvement était constitué de 17 caméras optoélectroniques T160 et de 2 caméras vidéo Bonita (Vicon™). Les mouvements étudiés étaient : la fermeture « simple » (non forcée) des paupières, la fermeture forcée des paupières, la protrusion labiale sur le son « o » [o], la protrusion labiale sur le son « pou » [pμ], et un sourire volontaire découvrant les dents. Lors de ces mouvements, nous avons enregistré et analysé le déplacement de 111 marqueurs réfléchissants de 1.5mm placés sur la face des sujets. Pour les cinq mouvements réalisés, nous avons obtenu des données quantitatives. Celles-ci nous ont permis d’identifier les zones d’action pour chacun des mouvements, de mesurer l’amplitude des déplacements et d’obtenir des données comparables dans le temps. Par ailleurs, le protocole mis en place a été évalué et sa réalisation est compatible avec une application clinique. L’analyse de la cinématique de la face est donc une technique appropriée à la clinique qui pourrait faciliter le diagnostic, le suivi et la rééducation des patients. Ce travail a permis de définir des mesures de référence qui constitueront la base d’un outil diagnostic, qu’il convient désormais de mettre en œuvre sur des patients. / The care of facial paralysis is often complex and therefore requires monitoring over the long term. There are many clinical severity scores with varying levels of sensitivity to assess the deficit of facial movement, but most of them are qualitative. The number of assessment methods is an obstacle to monitor patients and treatment evaluation. We need an objective measurement tool to provide reliable measures of resting asymmetry, symmetry of voluntary movement and synkinesis. The aim of this study is to determine if the 3D motion capture of the face is compatible with these clinical criteria. A descriptive study using a 3-dimensional (3D) motion capture system were performed on healthy volunteers (n=30) age from 20 to 30 years. The motion capture system consists of 17 optoelectronic cameras at a frequency of 100Hz. We captured the movements of the face on healthy volunteers. We obtained absolute values: 3D coordinates and relative displacements. These data were free of manual measurements, and the use of 3D motion capture does not impede the facial movement. The average time of capture was less than 10 minutes. The measurements are painless for subjects. Data are collected in a computer and can be easily exported. These results show the feasibility of 3D motion capture of facial movement. The protocol used here could be standardized to be routinely relevant. lt was used in an experimental study to follow up recovery of a facial transplantation. This technique could help to overcome the uncertainty caused by subjective assessment and optimize therapeutic choices.

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