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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The research called Snapshots Fragments; a study of Bergsonian cinematographic mechanism in the Marcel Duchamp´s painting Nude Descending a Staircase, is based in arts and reflections in which paint is performed a study of the cinematic mechanism concept from the philosopher, Henri Bergson. The research starts from the questions about wich intersection point can exist between an art work and a philosophical concept, that were deeply relevant and fruitful in modernity with contemporary developments in both discussions: arts and philosophy. In other words, this work was done intending to find similarities and differences between Duchamp\'s painting and Bergson´s concept. The research was developed aiming to enable the dialogue establishment between art and philosophy, given through an element that would be the embrace of both: the movie. / A pesquisa intitulada Fragmentos instantâneos, um estudo do mecanismo cinematográfico bergsoniano na pintura Nu descendo uma escada de Marcel Duchamp, trata-se de uma pesquisa em fundamentos e reflexões em artes, no qual são realizados estudos da pintura Nu descendo uma escada , de Marcel Duchamp, e do conceito de mecanismo cinematográfico, do filósofo Henri Bergson. A pesquisa inicia-se a partir dos questionamentos sobre a possibilidade de haver um ponto de intersecção entre um trabalho em arte e um conceito filosófico, os quais foram profundamente relevantes na modernidade e profícuos de desdobramentos na contemporaneidade e, nas discussões tanto no campo das artes, quanto na filosofia. Em outras palavras este trabalho foi realizado objetivando-se verificar em quais aspectos há convergências e divergências entre a pintura de Duchamp e o conceito de Bergson. A pesquisa foi realizada visando possibilitar a instauração de um diálogo entre arte e filosofia, dado através de um elemento que seria o amplexo de ambos, o cinema. / Mestre em Artes

O objetivo deste estudo foi avaliar, pelo método dos elementos finitos bidimensional, a distribuição das tensões geradas nas estruturas de suporte das próteses parciais removíveis (PPR) - osso cortical, osso esponjoso, fibromucosa e ligamento periodontal, em modelos de arcos parcialmente dentados de extremidade livre inferior, em rebordo horizontal (MA) e descendente-ascendente (MB). Foram confeccionados dois modelos de quadrante de mandíbula em AUTOCAD 2004 (Autodesk Inc., USA), contendo apenas o primeiro pré-molar e rebordo residual, sendo repostos o segundo pré-molar e primeiro molar pela PPR, tendo como dente suporte o primeiro pré-molar com apoio oclusal distal. Posteriormente, foi aplicada carga axial de 100 N nas cúspides dos dentes artificiais da PPR (somente sobre o 1 o molar - C1 e somente sobre o 2 o pré-molar - C2). Os modelos confeccionados em AUTOCAD foram transferidos para o programa I-DEAS (software de elementosfinitos), que discretizou-os e realizou a distribuição das tensões sob as condições de aplicação de carga citadas. Pôde–se observar que no osso esponjoso, a maior deformação e tensão de compressão foram observadas ao redor do dente suporte, principalmente no terço cervical distal para a deformação e no ápice do dente para a tensão de compressão durante a aplicação de carga sobre o segundo pré-molar no rebordo horizontal (0,003 mm e 0,621 N/mm 2 , respectivamente). Já no rebordo descendente-ascendente, as áreas solicitadas foram as mesmas, apresentando deformação e tensão de compressão máximas de 0,003 mm e 0,609 N/mm 2 . Para a fibromucosa, pode-se notar que no rebordo horizontal, a maior deformação e tensão de compressão ocorreram abaixo do ponto de aplicação de carga, ou seja, no primeiro molar, com valores de 0,137 mm e 0,144 N/mm 2 . No rebordo descendente-ascendente, a área de maior deformação e tensão de compressão localizaram-se na porção ascendente do rebordo em direção do trígono retromolar, com valores de 0,131 mm e 0,122 N/mm 2 , respectivamente. Diante dos limites do presente estudo pode-se concluir que: 1 - O osso cortical apresenta uma concentração de tensões maior que o osso esponjoso; 2 – O osso cortical apresenta uma deformação mais restrita em área que o osso esponjoso; 3 - O rebordo descendente-ascendente com a aplicação de carga sobre o primeiro molar (MB-C1) apresenta a maior deformação da fibromucosa quando comparada à deformação sofrida pelo ligamento periodontal, na proporção de 10:1; 4 - O rebordo descendente-ascendente apresenta uma distribuição de tensões menos favorável que o rebordo horizontal; 5 - A aplicação de carga no primeiro molar gera mais torque sobre o dente para distal do que a aplicação de carga sobre o segundo pré-molar. / This study is a two-dimensional finite element analysis (FEA) of the stress distributionin the supporting structures – compact and cancellous bone; periodontal ligament and oral mucosa – for a distal extension base removable partial denture (RPD) modeled on mandibular dental archs with two residual ridge forms: horizontal and descending-ascending. The two experimental quadrant models were developed in the AUTOCAD 2004 (Autodesk Inc., USA), software to include the first premolar asthe dental support with a distal occlusal rest; the second premolar and first molar as the artificial teeth inserted on the base over an RPD framework and the residual ridge. These models were discretized on the FEA software (I-DEAS, USA) and an axial load of 100 N was applied to the mesh on the artificial teeth cusps either on the first mola r (C1) or on the second premolar (C2). It was noticed that, in the cancellous bone, the maximum strain was around the supporting tooth, mainly in the distalcervical third (0.003 mm) while the largest compression tension (CT) was at the tooth apex when the load was applied over the second premolar, with a horizontal residual ridge (0,621 N/mm 2 ). When the ridge was descending-ascending, the areas affected were the same, showing 0,003 mm and 0,609 N/mm 2 , respectively as the maximum displacement and CT. In the oral mucosa, the largest results occurred when the load application point was over the first molar and the residual ridge was horizontal: 0,137 mm and 0,144 N/mm 2 . The descending-ascending alveolar ridge showed the maximum displacement and CT in the ascending segment of the residual ridge, toward the retromolar trigon, with 0,131 mm and 0,122 N/mm 2 , respectively. Within the constraints of this study, it was concluded that: 1 – The compact bone shows greater stress concentration than the cancellous bone; 2 – The compact bone shows greater area displacement concentration than the cancellous bone; 3 – The descending-ascending residual ridge with the load application on the first molar showed the largest displacement of the oral mucosa when compared to the periodontal ligament displacement with a 10:1 ratio; 4 – The descending-ascending residual ridge had a less favourable stress distribution than its horizontal counterpart; 5 – The load applied on the first molar produced more distal torquing on the supporting tooth than that on the second premolar.

Nesta pesquisa, foi realizada uma análise comparativa, por meio do método dos elementos finitos bidimensional linear, das deformações e tensões geradas a partir da aplicação de uma carga de 100N, nas estruturas de suporte (fibromucosa,ligamento periodontal, osso cortical e osso esponjoso) de dois modelos que simulam um hemiarco mandibular associada a uma prótese parcial removível de extremidade livre dista inferiorl, quando da variação da inclinação do rebordo residual no plano sagital. O modelo A (MA) foi desenhado com um rebordo ascendente distal com 15 graus de inclinação e o modelo B (MB) com um rebordo descendente distal com 15 graus negativos, ambos em relação ao plano oclusal. Nos dois modelos aplicou-se uma carga primeiramente na cúspide médio-vestibular do primeiro molar inferior artificial (C1) e depois na cúspide vestibular do segundo pré-molar inferior (C2), por meio do programa I-deas (software de elementos finitos) onde foram feitas as análises de deformações e tensões e processamento das imagens. Fez-se então uma análise comparativa dos carregamentos (C1 e C2) em cada modelo individualmente e entre os dois modelos(MA e MB). Os resultados permitiram concluir que: 1) A inclinação do rebordo residual no plano sagital influenciou na distribuição e na intensidade das tensões das estruturas de suporte; 2) No osso cortical as tensões foram mais localizadas e de maior intensidade que no osso esponjoso; 3) A diferença de deformação entre fibromucosa e ligamento periodontal foi maior quando a carga foi aplicada no primeiro molar, de ambos os modelos, sendo a mais expressiva no rebordo ascendente distal; 4) As tensões de compressão foram maiores em intensidade e melhor distribuídas no osso esponjoso e no osso cortical, quando comparadas as tensões de tração; 5) O rebordo ascendente distal se mostrou mais favorável à distribuição das tensões nas estruturas de suporte quando comparado ao rebordo descendente distal; 6) Nos dois modelos a aplicação da carga no primeiro molar gerou um maior torque sobre o dente suporte para a distal do que quando aplicado no segundo pré-molar, principalmente no rebordo descendente distal; 7) As estruturas de suporte do rebordo residual foram mais solicitadas em C1 que em C2, em ambos os modelos, principalmente no rebordo ascendente distal; 8) No dente suporte as tensões nas estruturas de suporte foram mais axiais quando o carregamento ocorreu no segundo pré-molar inferior, em ambos os modelos. / In this study, a two-dimensional finite element comparative analysis of the stress distribution and of displacement in the supporting structures – oral mucosa,periodontal ligament, compact and cancellous bone – was carried out for a distal extension base removable partial denture (RPD), modeled on two mandibular dental archs with different types of residual ridge when aplaying loads of 100N. The A model (MA) was developed to include a distal ascending alveolar ridge with a 15-degrees positive inclination, while the B model (MB) was prepared with a distal descending alveolar ridge with a 15-degrees negative inclination. Both models had a load applied inicially on the lower first molar median cusp (C1) and then on the lower second premolar buccal cusp (C2). Using the FEA software (I-DEAS, USA) for the stress distribution and displacement analysis of the generated images. A comparative analysis was them performed on the C1 and C2 loads for which and both models (MA and MB).The results showed that: 1 – The alveolar ridge inclination showed some degree of on the stress distribution and intensity generated by the RPD; 2 –The compact bone showed greater stress concentration and intensity than the cancellous bone; 3 – The ratio between oral mucosa and periodontal ligament displacement showed greater values when load was applied on the lower first molar for both models. The ratio was higher for the distal ascending alveolar ridge; 4- The compressive stress showed greater intensity and better range of distribution than the tensile stress for both the compact and cancellous bone; 5 – The distal ascending residual ridge had a more favourable stress distribution than distal descending conterpart ; 6 – The load applied on the lower first molar produced more distal torquing on the supporting tooth than that on the lower second premolar ,specially on the distal descending residual ridge; 7 – the load applied on the lower firt molar generated greater amount of stress on the residual ridge supporting structures for both models, but specially for the distal ascending residual ridge; 8 – The load applied on the lower second premolar produced more vertical forces on the supporting structures of the tooth for both models.

Introduction: Cardiovascular surgery is a relatively young but progressively evolving field in medicine. More specifically, in the past decades, cardiac surgery achieved significant advances in understanding the causes, progression and treatments of ischemic heart disease (IHD). The IHD is the most common coronary disease, and it ranks first in morbidity and mortality in the developed world. It justifies the need for significant fundamental research as well as its study in clinical practice. It now includes specialized cardiovascular centres with the complex specialized treatments. A group of interventional cardiologists capable of performing routine examinations of the coronary veins using selective angiography has been established. They can eventually also perform percutaneous coronary interventions with direct stent implants. Thus the advances have been made in comprehensive indication of the patients towards their optimal treatments under the regime of a cardio-team. Such team comprises of a cardio-surgeon, interventional cardiologist, echocardiography specialist and the attending physician who is usually the cardiologist. The IHD treatments involve preventive cardiology with the regime measures and checks, pharmacotherapy, interventional cardiology and cardiac surgery to spa treatment and...

Les angrecoïdes constituent le groupe d'orchidées épiphytes le plus diversifié dans les Afrotropiques, comprenant environ 800 espèces. Bien que beaucoup d'attention leur aient été porté, certaines énigmes taxonomiques subsistent au sein des angraecoïdes, et les facteurs à l'origine de leur diversification rapide sont encore inconnus. Les angraecoïdes présentent une remarquable diversité en termes du nombre chromosomique, en faisant un système très approprié pour explorer l'impact des changements caryotypiques sur la cladogenèse, les taux de spéciation/extinction et la diversification morphologique dans le contexte des fluctuations climatiques en Afrique tropicale depuis le Miocène. En outre, grâce au large éventail des longueurs d'éperon nectarifère que ces orchidées présentent, elles ont fait l'objet, depuis Darwin, de recherches approfondies dans le cadre des interactions plantes-animaux. Ici, sur base de nouveaux arbres phylogénétiques produits en utilisant ITS-1 ainsi que cinq marqueurs plastidiques et englobant environ 40 % des espèces, nous fournissons un nouveau cadre taxonomique pour les principales lignées d'Angraecinae. De plus, le cadre taxonomique des angraecoïdes est mis à jour avec, notamment, la description de trois nouveaux genres et six nouvelles espèces. Cette nouvelle hypothèse phylogénétique nous a permis d'étudier si les changements des caryotypes et des pollinisateurs ont pu être les moteurs de la radiation évolutive des angraecoïdes. La reconstruction des états ancestraux du nombre chromosomique révèle une histoire caryotypique dominée par la dysploïdie descendante en Afrique tropicale continentale, où environ 90 % des espèces dérivent d'au moins un changement inféré de n = 17–18 à n = 25 au Miocène moyen. L’examen des intervalles de position du nectar par rapport au pollen dans les Afrotropiques a révélé qu'environ 3 % de la flore des angiospermes de Madagascar est probablement pollinisée par des sphinx, alors que cette proportion est d'environ 1,6 % en Afrique continentale. Les nombreux changements de guilde de pollinisateur vers la sphingophilie ayant eu lieu chez les angraecoïdes seraient à l’origine d’environ 31 % des espèces, y compris certaines lignées ayant les taux de spéciation les plus élevés. En dehors du domaine de la sphingophilie, de nouveaux exemples possibles d’ornithophilie, de phalénophilie et de pollinisation par des tipules à long proboscis/microlepidoptères sont discutées. Des perspectives de recherche concernant l'évolution génomique chez les angraecoïdes et l'impact et les mécanismes des changements des sites de fixation des pollinies sont suggérées. Enfin, certaines priorités pour l’observation de nouveaux pollinisateurs sur le terrain et les frontières de l’alpha et bêta-taxonomie chez les angraecoïdes sont présentées. / Doctorat en Sciences / info:eu-repo/semantics/nonPublished

Indiana University-Purdue University Indianapolis (IUPUI) / After spinal cord injury (SCI), poor axonal regeneration of the central nervous system, which mainly attributed to glial scar and low intrinsic regenerating capacity of severely injured neurons, causes limited functional recovery. Combinatory strategy has been applied to target multiple mechanisms. Schwann cells (SCs) have been explored as promising donors for transplantation to promote axonal regeneration. Among the central neurons, descending propriospinal neurons (DPSN) displayed the impressive regeneration response to SCs graft. Glial cell line-derived neurotrophic factor (GDNF), which receptor is widely expressed in nervous system, possesses the ability to promote neuronal survival, axonal regeneration/sprouting, remyelination, synaptic formation and modulate the glial response. We constructed a novel axonal permissive pathway in rat model of thoracic complete transection injury by grafting SCs over-expressing GDNF (SCs-GDNF) both inside and caudal to the lesion gap. Behavior evaluation and histological analyses have been applied to this study. Our results indicated that tremendous DPSN axons as well as brain stem axons regenerated across the lesion gap back to the caudal spinal cord. In addition to direct promotion on axonal regeneration, GDNF also significantly improved the astroglial environment around the lesion. These regenerations caused motor functional recovery. The dendritic plasticity of axotomized DPSN also contributed to the functional recovery. We applied a G-mutated rabies virus (G-Rabies) co-expressing green fluorescence protein (GFP) to reveal Golgi-like dendritic morphology of DPSNs and its response to axotomy injury and GDNF treatment. We also investigated the neurotransmitters phenotype of FluoroGold (FG) labeled DPSNs. Our results indicated that over 90 percent of FG-labeled DPSNs were glutamatergic neurons. DPSNs in sham animals had a predominantly dorsal-ventral distribution of dendrites. Transection injury resulted in alterations in the dendritic distribution, with dorsal-ventral retraction and lateral-medial extension of dendrites. Treatment with GDNF significantly increased the terminal dendritic length of DPSNs. The density of spine-like structures was increased after injury and treatment with GDNF enhanced this effect.

Introduction: Cardiovascular surgery is a relatively young but progressively evolving field in medicine. More specifically, in the past decades, cardiac surgery achieved significant advances in understanding the causes, progression and treatments of ischemic heart disease (IHD). The IHD is the most common coronary disease, and it ranks first in morbidity and mortality in the developed world. It justifies the need for significant fundamental research as well as its study in clinical practice. It now includes specialized cardiovascular centres with the complex specialized treatments. A group of interventional cardiologists capable of performing routine examinations of the coronary veins using selective angiography has been established. They can eventually also perform percutaneous coronary interventions with direct stent implants. Thus the advances have been made in comprehensive indication of the patients towards their optimal treatments under the regime of a cardio-team. Such team comprises of a cardio-surgeon, interventional cardiologist, echocardiography specialist and the attending physician who is usually the cardiologist. The IHD treatments involve preventive cardiology with the regime measures and checks, pharmacotherapy, interventional cardiology and cardiac surgery to spa treatment and...

Magnetic resonance images (MRI) are acquired by sampling the current of induced electromotiveforce (EMF). EMF is induced due to flux of the net magnetic field from coherent nuclear spins with intrinsic magnetic dipole moments. The spins are excited by (non-ionizing) radio frequency electromagnetic radiation in conjunction with stationary and gradient magnetic fields. These images reveal detailed internal morphological structures as well as enable functional assessment of the body that can help diagnose a wide range of medical conditions. The aim of this project was to unwrap phase contrast cine magnetic resonance images, targeting the great vessels. The maximum encoded velocity (venc) is limited to the angular phase range [-π, π] radians. This may result in aliasing if the venc is set too low by the MRI personnel. Aliased images yield inaccurate cardiac stroke volume measurements and therefore require acquisition retakes. The retakes might be avoided if the images could be unwrapped in post-processing instead. Using computer vision, the angular phase of flow measurements as well as the angular phase of retrospectively wrapped image sets were unwrapped. The performances of three algorithms were assessed, Laplacian algorithm, sequential tree-reweighted message passing and iterative graph cuts. The associated energy formulation was also evaluated. Iterative graph cuts was shown to be the most robust with respect to the number of wraps and the energies correlated with the errors. This thesis shows that there is potential to reduce the number of acquisition retakes, although the MRI personnel still need to verify that the unwrapping performances are satisfactory. Given the promising results of iterative graph cuts, next it would be valuable to investigate the performance of a globally optimal surface estimation algorithm.

Le système auditif possède deux particularités. En périphérie, les mécanismes cochléaires actifs (MCA), sous-tendus par la motilité des cellules ciliées externes (CCE), interviennent dans la sensibilité auditive et la sélectivité fréquentielle. Sur le versant central, le système efférent olivocochléaire médian (SEOCM), qui se projette sur les CCE et module les MCA, améliore la perception auditive en milieu bruité. Sur le plan exploratoire, ces deux processus peuvent être évalués grâce aux otoémissions acoustiques provoquées (OEAP) et leur suppression controlatérale. Par ailleurs, des résultats expérimentaux chez l’animal ont montré l’existence d’un rétrocontrôle exercé par le système auditif corticofuge descendant (SACD) sur la cochlée, via le SEOCM.Le présent travail comporte trois études réalisées chez l’humain, visant à explorer les interactions entre SACD, SEOCM et MCA. Les études 1 et 2, utilisant une méthodologie innovante chez des patients épileptiques réalisant une stéréo-électroencéphalographie, ont révélé un effet atténuateur différentiel de la stimulation électrique intracérébrale sur l’amplitude des OEAP, en fonction des modalités de stimulation, ainsi qu’une variabilité de cet effet selon les caractéristiques de l’épilepsie. L’étude 3 a montré un renforcement bilatéral de l’activité du SEOCM chez des musiciens professionnels.Pris dans leur ensemble, ces résultats fournissent d’une part, des arguments directs et indirects en faveur de l’existence d’un SACD fonctionnel chez l’humain. D’autre part, des phénomènes de plasticité à long terme, pathologique ou supranormale, seraient susceptibles de modifier l’activité de cette voie cortico-olivocochléaire. / The auditory system has two special features. At peripheral level, active cochlear micromechanisms (ACM), underlain by motility of outer hair cells (OHC), are involved in auditory sensitivity and frequency selectivity. At central level, the medial olivocochlear efferent system (MOCES), which directly projects onto OHC to modulate ACM, improves auditory perception in noise. From an exploratory point of view, both processes can be assessed through transient evoked otoacoustic emissions (TEOAE) and the procedure of contralateral suppression. In addition, experimental data in animals have disclosed a top-down control exerted by corticofugal descending auditory system (CDAS) on cochlea, via MOCES.The present work comprises three studies carried out in human, aiming to investigate interactions between CDAS, MOCES and ACM. The first and second studies, based on an innovative experimental procedure in epileptic patients undergoing presurgical stereoelectroencephalography, have revealed a differential attenuation effect of intracerebral electrical stimulation on TEOAE amplitude depending on stimulation modalities, as well as a variability of this effect depending on the clinical history of epilepsy. The third study has shown a bilateral enhancement of MOCES activity in professional musicians.Taking together, these results provide direct and indirect evidence for the existence of a functional CDAS in humans. Moreover, possible long-term plasticity phenomenon, either pathological –as in epileptic patients– or supernormal –as in professional musicians– may change cortico-olivocochlear activity.