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Made available in DSpace on 2014-06-11T19:23:41Z (GMT). No. of bitstreams: 0 Previous issue date: 2003Bitstream added on 2014-06-13T20:50:53Z : No. of bitstreams: 1 faleiros_hrp_me_botfm.pdf: 3828651 bytes, checksum: f47c794e8ad9195b3ee57735bbb7fc38 (MD5) / O retalho retroauricular é um retalho já bem conhecido em cirurgia reparadora, tanto na sua versão pediculada, como livre. Trata-se de um retalho cutâneo da região retroauricular e mastoidiana, podendo ser tanto a pedículo inferior, baseado nos vasos auriculares posteriores, como superior, baseado nos vasos temporais superficiais. É considerado ideal na reconstrução facial, devido às suas características como coloração e textura da pele. Porém, o pedículo curto, de pequeno calibre, assim como a variabilidade anatômica dos vasos auriculares posteriores, associados ao problema de aporte vascular arterial e drenagem venosa no retalho a pedículo superior, colocaram este retalho como uma opção secundária em reconstruções faciais. No presente trabalho, estudamos os vasos auriculares anteriores, posteriores e temporais superficiais em 15 cadáveres (8 frescos e 7 formolizados), pesquisando todos os seus sistemas anastomóticos. Descrevemos, igualmente, uma nova maneira de elevação do retalho axial retroauricular fasciocutâneo a fluxo retrógrado (pedículo superior), no qual acreditamos tê-lo tornado mais seguro tanto no plano arterial como venoso. O retalho é pediculado no ramo frontal da artéria temporal superficial, incluindo no pedículo os ramos descendentes da artéria parietal e a artéria auricular superior. Demonstramos ainda que o pavilhão auricular remanescente após a elevação do retalho é bem vascularizado, com poucos riscos de sofrimento vascular. / The retroauricular flap is well known in reconstructive surgery, both in its pedicled and free versions. This is a skin flap from the retroauricular region; it can be either an inferior pedicle based on the postauricular vessels or a superior one based on the superficial temporal vessels. It is ideal for facial reconstruction due to its characteristics such as skin color and texture. However, the small-caliber short pedicle and the postauricular vessel anatomical variability, associated with the problematic arterial supply and venous insufficiency to the superior pedicle flap, have left this as a secondary option. In this work, we have studied the postauricular and superficial temporal vessels in 15 cadavers (8 fresh and 7 in formaldehyde), analyzing all anastomotic systems. We have also described a new method for elevating the retroauricular fasciocutaneous axial flap to retrograde flow (superior pedicle), which we believe it is safer both in the arterial and venous planes. The flap is pedicled in the frontal branch of the superficial temporal artery, including the descending branches of the parietal artery and the superior auricular artery in the pedicle. We have also demonstrated that the remaining external ear is well vascularized after flap elevation, with less risk of vascular suffering.

Resumo: O retalho retroauricular é um retalho já bem conhecido em cirurgia reparadora, tanto na sua versão pediculada, como livre. Trata-se de um retalho cutâneo da região retroauricular e mastoidiana, podendo ser tanto a pedículo inferior, baseado nos vasos auriculares posteriores, como superior, baseado nos vasos temporais superficiais. É considerado ideal na reconstrução facial, devido às suas características como coloração e textura da pele. Porém, o pedículo curto, de pequeno calibre, assim como a variabilidade anatômica dos vasos auriculares posteriores, associados ao problema de aporte vascular arterial e drenagem venosa no retalho a pedículo superior, colocaram este retalho como uma opção secundária em reconstruções faciais. No presente trabalho, estudamos os vasos auriculares anteriores, posteriores e temporais superficiais em 15 cadáveres (8 frescos e 7 formolizados), pesquisando todos os seus sistemas anastomóticos. Descrevemos, igualmente, uma nova maneira de elevação do retalho axial retroauricular fasciocutâneo a fluxo retrógrado (pedículo superior), no qual acreditamos tê-lo tornado mais seguro tanto no plano arterial como venoso. O retalho é pediculado no ramo frontal da artéria temporal superficial, incluindo no pedículo os ramos descendentes da artéria parietal e a artéria auricular superior. Demonstramos ainda que o pavilhão auricular remanescente após a elevação do retalho é bem vascularizado, com poucos riscos de sofrimento vascular. / Abstract: The retroauricular flap is well known in reconstructive surgery, both in its pedicled and free versions. This is a skin flap from the retroauricular region; it can be either an inferior pedicle based on the postauricular vessels or a superior one based on the superficial temporal vessels. It is ideal for facial reconstruction due to its characteristics such as skin color and texture. However, the small-caliber short pedicle and the postauricular vessel anatomical variability, associated with the problematic arterial supply and venous insufficiency to the superior pedicle flap, have left this as a secondary option. In this work, we have studied the postauricular and superficial temporal vessels in 15 cadavers (8 fresh and 7 in formaldehyde), analyzing all anastomotic systems. We have also described a new method for elevating the retroauricular fasciocutaneous axial flap to retrograde flow (superior pedicle), which we believe it is safer both in the arterial and venous planes. The flap is pedicled in the frontal branch of the superficial temporal artery, including the descending branches of the parietal artery and the superior auricular artery in the pedicle. We have also demonstrated that the remaining external ear is well vascularized after flap elevation, with less risk of vascular suffering. / Orientador: Fausto Viterbo de Oliveira Neto / Coorientador: Jacques Baudet / Coorientador: Vincent Casoli / Mestre

Com o desenvolvimento dos motores turbofan, a contribuição das estruturas hipersustentadoras no ruído total gerado pelas aeronaves tem se tornado mais considerável. Sendo que as estruturas do flape tornaram-se uma das principais fontes de ruído. Dispositivos para redução do nível sonoro nessas regiões são investigados em uma asa MD 30P30N, ensaiada em um túnel de vento adaptado para medições aeroacústicas. A localização das fontes de ruído foi obtida através de uma antena de Beamforming (técnica de identificação de fontes acústicas) com 109 microfones, dos quais 60 deles são de alta freqüência (até 40 kHz). As características aerodinâmicas foram avaliadas através de medidas de pressão na superfície do modelo, e com o mapeamento de vórtice em ponta de flape. Dentre os dispositivos avaliados para redução de ruído, foram testadas chapas porosas de diversos tamanhos. Os sinais dos microfones foram processados com o algoritmo DAMAS2 para obtenção dos espectros do Beamforming em uma região de interesse definida. As configurações com porosidade têm nível de ruído equivalente para freqüências até 2000 Hz. A partir daí, há uma redução de até 6 dB em 3200 Hz em relação ao baseline (tipo de teste aplicado à asa). Os resultados de Beamforming para duas configurações diferentes, baseline e chapa porosa foram apresentados usando uma faixa dinâmica de 12 dB, com pico de 58 dB. Observa-se que houve redução dos níveis de ruído na região selecionada. A perda de pressão total na ponta do flape mostrou que há uma aparente correlação entre o gradiente da pressão total e o nível de ruído. Estudos adicionais são necessários para entender os mecanismos de redução de ruído e assim otimizar a geometria das chapas porosas. No entanto, os resultados apresentados indicam que esses dispositivos são candidatos para aplicação em aeronaves. / With the development of high-bypass turbofan engines, the airframe contribution to the total aircraft noise has become considerable. One of the largest sources of airframe noise is the flap side-edge, which is investigated experimentally in a MD 30P30N wing. Several devices are also tested to reduce the side-edge noise, especially porous plates. Wind tunnel testing is carried out and the position of noise sources and their levels is obtained with a beamforming antenna. It has 112 microphones, in which 60 of them are suitable for acoustic measurements of up to 40 kHz. The aerodynamic characteristics are evaluated with pressure measurements on the model surface, as well as with vortex mapping on the flap side-edge. To evaluate the noise levels, microphone signals were processed with the DAMAS2 algorithm. Beamforming spectra were then obtained considering only the side-edge region. The baseline configuration and those with porous plates were tested and equivalent noise levels were obtained up to 2000 Hz. For higher frequencies, the model with porous plates has a lower noise level, reaching a difference of 6 dB in 3200 Hz, compared to the baseline configuration. Vortex mapping was carried out with a seven hole Pitot probe developed at the University for the measurement of flows with high angularity. The results for the baseline configuration allows to correlate aerodynamic and aeroacoustic data. This helps to design the side-edge region with a low noise level. Additional studies are necessary to understand the mechanisms of noise reduction and to optimize the geometry of the porous plate. However, the presented results indicate that this device is a candidate for application in aircraft, in special by its superior durability compared to the foam generally used for noise attenuation.

Genomic DNA is under constant assault by environmental factors that introduce a variety of DNA lesions. Cells evolved several DNA repair and recombination mechanisms to remove these damages and ensure the integrity of the DNA material. A variety of specific proteins, called nucleases, processes toxic DNA structures that deviate from the heritable duplex DNA as common pathway intermediates. DNA-induced protein ordering is a common feature in all DNA repair nucleases. Still, the conformational requirement of the DNA and the protein and how they control the catalytic selectivity of the nuclease remain largely unknown. This study focus on the bases of catalytic activity of a protein belongs to the 5’ nuclease super-family called the human Flap endonuclease 1 (FEN1); it removes excess 5’ flaps that are generated during DNA replication. hFEN1 mutations and over-expression had been linked to a variety of cancers. This thesis aims to study the structural and dynamic properties of free hFEN1 and the catalytic activity of DNA-bound hFEN1 in solution utilizing the modern high-resolution multidimensional Nuclear Magnetic Resonance (NMR) spectroscopy. It was possible to depict the secondary structure and backbone conformation in solution of wild type (WT) hFEN1 by the usage of the improved list of assigned resonances, derived from the NMR 2D and 3D ¹⁵N-detected experiments and compared to the assignment with the previously published resonance assignment (BMRB id: 27160). I was successfully assigned the new spectrum and enhanced it by assigning seven more residues. Moreover, we tested the interaction of 1:10 ratio of hFEN1-Ca2+ with DNA by the ¹³C-detected 2D CACO experiment. The results indicate hFEN1:DNA interaction. Furthermore, parts of hFEN1 get more ordered/structured once DNA appears, thus we recorded the protein flexibly by 2D ¹H-¹⁵N TROSY-HSQC using the relaxation rate parameters: longitudinal R1, transverse R2 complemented with ¹⁵N-{¹H} NOEs (heteronuclear Overhauser enhancement). It was found that the overall molecular architecture is rigid, and the highest flexibility lies in the α2-α3 loop and arch (α4-α5) regions. Further analysis is needed to understand more profoundly the activity of hFEN1 in an atomic level by inducing mutations and testing the protein in various environmental conditions.

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In this paper we develop a mathematical model of a two-dimensional aeroelastic airfoil. This model is used to design a flutter suppression controller. Flutter is a vibration in a wing caused by airstream energy being absorbed by the lifting surface. Flutter increases with increasing speed. For simplicity, we consider a flat plate in a two-dimensional flow. The model is developed in the frequency domain and then transformed into the time domain. The uncontrolled model is numerically simulated using MATLAB. Linear Quadratic Regulator (LQR) theory is used to design a state feedback controller. The LQR control scheme consists of using a full state feedback controller of the form u=-Kx, where K is a control gain matrix. The goal is to use LQR theory to supress flutter and to maintain stability of the closed loop system. / Master of Science

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This thesis presents a study on the design and analysis of a morphing flap structure integrated with actuation mechanism for potential application to large aircraft. Unlike the conventional rigid flap mounted on the wing trailing edge, the morphing flap is designed as a unitized structural system integrated with three primary components: the upper and lower flexible skins reinforced by stringers, an eccentric beam actuation mechanism (EBAM) with discs fixed on it, and the connection of the discs with the stringers. Based on the EBAM concept proposed by Dr Guo in previous research [1], the current study has been focused on the EBAM design and optimization, kinematic simulation and structural modelling of the morphing flap. Although a lot of efforts have been made to develop the morphing flap in previous research, it is lack of detailed design of the disc-skin linkage and clear view on the mechanism optimization in relation to the shape requirement. The main objective of this research is to meet the morphing shape requirements and calculate the actuation torque for a specified morphing flap. Firstly effort was made to design and optimize the disc shape and locations in the EBAM for the best matching of the specified morphing shape with minimum actuation torque demand. It is found that minimum three discs are required and their locations have little effect on the actuation torque. Secondly attention was focused on designs of the disc and a C-linkage with the stringers. To ensure that the C- linkage works in practice, a twisted stringer flange design was proposed. Thirdly the actuation mechanism was integrated with the stiffened skin to play the role of an active rib in the flap structure. Based on the design, FE modelling and analysis of the morphing flap structure was carried out. The behaviour of the morphing flap under the internal actuation and external aerodynamic load was applied for stress analysis and detailed design of the structures. Finally the kinematics of the integrated morphing flap was simulated by using CATIA to demonstrate the feasibility and the effectiveness of the improved design.