Palaeomagnetic study of a subaerial volcanic ridge (Sao Jorge Island, Azores) for the past 1.3 Myr: evidence for the Cobb Mountain Subchron, volcano flank instability and tectonomagmatic implications

We present a palaeomagnetic study on 38 lava flows and 20 dykes encompassing the past 1.3 Myr on S. Jorge Island (Azores ArchipelagoNorth Atlantic Ocean). The sections sampled in the southeastern and central/western parts of the island record reversed and normal polarities, respectively. They indicate a mean palaeomagnetic pole (81.3 degrees N, 160.7 degrees E, K= 33 and A95= 3.4 degrees) with a latitude shallower than that expected from Geocentric Axial Dipole assumption, suggesting an effect of non-dipolar components of the Earth magnetic field. Virtual Geomagnetic Poles of eight flows and two dykes closely follow the contemporaneous records of the Cobb Mountain Subchron (ODP/DSDP programs) and constrain the age transition from reversed to normal polarity at ca. 1.207 +/- 0.017 Ma. Volcano flank instabilities, probably related to dyke emplacement along an NNWSSE direction, led to southwestward tilting of the lava pile towards the sea. Two spatially and temporally distinct dyke systems have been recognized on the island. The eastern is dominated by NNWSSE trending dykes emplaced before the end of the Matuyama Chron, whereas in the central/western parts the eruptive fissures oriented WNWESE controlled the westward growth of the S. Jorge Island during the Brunhes Chron. Both directions are consistent with the present-day regional stress conditions deduced from plate kinematics and tectonomorphology and suggest the emplacement of dykes along pre-existing fractures. The distinct timing and location of each dyke system likely results from a slight shift of the magmatic source.

Juntas mecânicas em material compósito

O âmbito da presente tese é o estudo de juntas mecânicas em material compósito realizado com fibra de vidro. Os materiais compósitos são a solução procurada pela generalidade dos sectores da indústria, devido essencialmente à sua grande capacidade estrutural e à sua resistência mecânica específica, ou seja, a resistência mecânica versus peso ser em geral maior que nas ligações metálicas. O estudo efectuado neste trabalho é referente à delaminação presente na furação de materiais compósitos, sendo esta um dos problemas de maior gravidade, existente quando se realiza a furação do material. Este problema influência a integridade estrutural do material bem como a sua fiabilidade a longo prazo. Foram usados dois métodos de furação, o primeiro conhecido por furação convencional e o segundo habitualmente designado método KTH ou por furação orbital. Foi feita uma comparação entre estes dois métodos e verificado qual deles apresenta menor delaminação em torno do furo e melhor qualidade de furo. Conclui-se que a furação orbital apresenta uma delaminação inferior relativamente à furação convencional, e que esta é preferível para a realização de furação em material compósito.

Simulation of the Magnetic Induction Vector of a Magnetic Core to be Used in FFC NMR Relaxometry

This paper is a contribution for the assessment and comparison of magnet properties based on magnetic field characteristics particularly concerning the magnetic induction uniformity in the air gaps. For this aim, a solver was developed and implemented to determine the magnetic field of a magnetic core to be used in Fast Field Cycling (FFC) Nuclear Magnetic Resonance (NMR) relaxometry. The electromagnetic field computation is based on a 2D finite-element method (FEM) using both the scalar and the vector potential formulation. Results for the magnetic field lines and the magnetic induction vector in the air gap are presented. The target magnetic induction is 0.2 T, which is a typical requirement of the FFC NMR technique, which can be achieved with a magnetic core based on permanent magnets or coils. In addition, this application requires high magnetic induction uniformity. To achieve this goal, a solution including superconducting pieces is analyzed. Results are compared with a different FEM program.

Formation of oriented nickel aggregates in rutile single crystals by Ni implantation

The magnetic and electrical properties of Ni implanted single crystalline TiO2 rutile were studied for nominal implanted fluences between 0.5 x 10(17) cm(-2) and 2.0 x 10(17) cm(-2) with 150 keV energy, corresponding to maximum atomic concentrations between 9 at% and 27 at% at 65 nm depth, in order to study the formation of metallic oriented aggregates. The results indicate that the as implanted crystals exhibit superparamagnetic behavior for the two higher fluences, which is attributed to the formation of nanosized nickel clusters with an average size related with the implanted concentration, while only paramagnetic behavior is observed for the lowest fluence. Annealing at 1073 K induces the aggregation of the implanted nickel and enhances the magnetization in all samples. The associated anisotropic behavior indicates preferred orientations of the nickel aggregates in the rutile lattice consistent with Rutherford backscattering spectrometry-channelling results. Electrical conductivity displays anisotropic behavior but no magnetoresistive effects were detected. (C) 2013 Elsevier B.V. All rights reserved.

Simulation of the magnetic induction vector of a magnetic core to be used in FFC NMR relaxometry

This paper is a contribution for the assessment and comparison of magnet properties based on magnetic field characteristics particularly concerning the magnetic induction uniformity in the air gaps. For this aim, a solver was developed and implemented to determine the magnetic field of a magnetic core to be used in Fast Field Cycling (FFC) Nuclear Magnetic Resonance (NMR) relaxometry. The electromagnetic field computation is based on a 2D finite-element method (FEM) using both the scalar and the vector potential formulation. Results for the magnetic field lines and the magnetic induction vector in the air gap are presented. The target magnetic induction is 0.2 T, which is a typical requirement of the FFC NMR technique, which can be achieved with a magnetic core based on permanent magnets or coils. In addition, this application requires high magnetic induction uniformity. To achieve this goal, a solution including superconducting pieces is analyzed. Results are compared with a different FEM program.

OPTIMAX 2014 - Radiation dose and image quality optimisation in medical imaging

Medical imaging is a powerful diagnostic tool. Consequently, the number of medical images taken has increased vastly over the past few decades. The most common medical imaging techniques use X-radiation as the primary investigative tool. The main limitation of using X-radiation is associated with the risk of developing cancers. Alongside this, technology has advanced and more centres now use CT scanners; these can incur significant radiation burdens compared with traditional X-ray imaging systems. The net effect is that the population radiation burden is rising steadily. Risk arising from X-radiation for diagnostic medical purposes needs minimising and one way to achieve this is through reducing radiation dose whilst optimising image quality. All ages are affected by risk from X-radiation however the increasing population age highlights the elderly as a new group that may require consideration. Of greatest concern are paediatric patients: firstly they are more sensitive to radiation; secondly their younger age means that the potential detriment to this group is greater. Containment of radiation exposure falls to a number of professionals within medical fields, from those who request imaging to those who produce the image. These staff are supported in their radiation protection role by engineers, physicists and technicians. It is important to realise that radiation protection is currently a major European focus of interest and minimum competence levels in radiation protection for radiographers have been defined through the integrated activities of the EU consortium called MEDRAPET. The outcomes of this project have been used by the European Federation of Radiographer Societies to describe the European Qualifications Framework levels for radiographers in radiation protection. Though variations exist between European countries radiographers and nuclear medicine technologists are normally the professional groups who are responsible for exposing screening populations and patients to X-radiation. As part of their training they learn fundamental principles of radiation protection and theoretical and practical approaches to dose minimisation. However dose minimisation is complex – it is not simply about reducing X-radiation without taking into account major contextual factors. These factors relate to the real world of clinical imaging and include the need to measure clinical image quality and lesion visibility when applying X-radiation dose reduction strategies. This requires the use of validated psychological and physics techniques to measure clinical image quality and lesion perceptibility.

Application of fractional order concepts in the study of electrical potential

The Maxwell equations, expressing the fundamental laws of electricity and magnetism, only involve the integer-order calculus. However, several effects present in electromagnetism, motivated recently an analysis under the fractional calculus (FC) perspective. In fact, this mathematical concept allows a deeper insight into many phenomena that classical models overlook. On the other hand, genetic algorithms (GA) are an important tool to solve optimization problems that occur in engineering. In this work we use FC and GA to implement the electrical potential of fractional order. The performance of the GA scheme and the convergence of the resulting approximations are analyzed.

NiII, CuII and ZnII complexes with a sterically hindered scorpionate ligand (TpmsPh) and catalytic application in the diasteroselective nitroaldol (Henry) reaction

The Ni-II and Zn-II complexes [MCl(Tpms(Ph))] (Tpms(Ph) = SO3C(pz(Ph))(3), pz = pyrazolyl; M = Ni 2 or Zn 3) and the Cu-II complex [CuCl(Tpms(Ph))(H2O)] (4) have been prepared by treatment of the lithium salt of the sterically demanding and coordination flexible tris(3-phenyl-1-pyrazolyl)methanesulfonate (Tpms(Ph))(-) (1) with the respective metal chlorides. The (Tpms(Ph))(-) ligand shows the N-3 or N2O coordination modes in 2 and 3 or in 4, respectively. Upon reaction of 2 and 3 with Ag(CF3SO3) in acetonitrile the complexes [M(Tpms(Ph))-(MeCN)](CF3SO3) (M = Ni 5 or Zn 6, respectively) were formed. The compounds were obtained in good yields and characterized by analytic and spectral (IR, H-1 and C-13{H-1} NMR, ESI-MS) data, density functional theory (DFT) methods and {for 4 and [(Bu4N)-Bu-n](Tpms(Ph)) (7), the tatter obtained upon Li+ replacement by [(Bu4N)-Bu-n](+) in Li(Tpms(Ph))} by single crystal X-ray diffraction analysis. The Zn-II and Cu-II complexes (3 and 4, respectively) act as efficient catalyst precursors for the diastereoselective nitroaldol reaction of benzaldehydes and nitroethane to the corresponding beta-nitroalkanols (up to 99% yield, at room temperature) with diastereoselectivity towards the formation of the anti isomer, whereas the Ni-II complex 2 only shows a modest catalytic activity.

X Radiation dose implications in screening patients with ferromagnetic IOFBs prior to MRI: a literary review

Patients scheduled for a magnetic resonance imaging (MRI) scan sometimes require screening for ferromagnetic Intra Orbital Foreign Bodies (IOFBs). To assess this, they are required to fill out a screening protocol questionnaire before their scan. If it is established that a patient is at high risk, radiographic imaging is necessary. This review examines literature to evaluate which imaging modality should be used to screen for IOFBs, considering that the eye is highly sensitive to ionising radiation and any dose should be minimised. Method: Several websites and books were searched for information, these were as follows: PubMed, Science Direct, Web of Knowledge and Google Scholar. The terms searched related to IOFB, Ionising radiation, Magnetic Resonance Imaging Safety, Image Quality, Effective Dose, Orbits and X-ray. Thirty five articles were found, several were rejected due to age or irrelevance; twenty eight were eventually accepted. Results: There are several imaging techniques that can be used. Some articles investigated the use of ultrasound for investigation of ferromagnetic IOFBs of the eye and others discussed using Computed Tomography (CT) and X-ray. Some gaps in the literature were identified, mainly that there are no articles which discuss the lowest effective dose while having adequate image quality for orbital imaging. Conclusion: X-ray is the best method to identify IOFBs. The only problem is that there is no research which highlights exposure factors that maintain sufficient image quality for viewing IOFBs and keep the effective dose to the eye As Low As Reasonably Achievable (ALARA).

Palaeomagnetic study of a subaerial volcanic ridge (São Jorge Island, Azores) for the cobb mountain subhron, volcano flank instability and tectonomagmatic implications

We present a palaeomagnetic study on 38 lava flows and 20 dykes encompassing the past 1.3 Myr on S. Jorge Island (Azores ArchipelagoNorth Atlantic Ocean). The sections sampled in the southeastern and central/western parts of the island record reversed and normal polarities, respectively. They indicate a mean palaeomagnetic pole (81.3 degrees N, 160.7 degrees E, K= 33 and A95= 3.4 degrees) with a latitude shallower than that expected from Geocentric Axial Dipole assumption, suggesting an effect of non-dipolar components of the Earth magnetic field. Virtual Geomagnetic Poles of eight flows and two dykes closely follow the contemporaneous records of the Cobb Mountain Subchron (ODP/DSDP programs) and constrain the age transition from reversed to normal polarity at ca. 1.207 +/- 0.017 Ma. Volcano flank instabilities, probably related to dyke emplacement along an NNWSSE direction, led to southwestward tilting of the lava pile towards the sea. Two spatially and temporally distinct dyke systems have been recognized on the island. The eastern is dominated by NNWSSE trending dykes emplaced before the end of the Matuyama Chron, whereas in the central/western parts the eruptive fissures oriented WNWESE controlled the westward growth of the S. Jorge Island during the Brunhes Chron. Both directions are consistent with the present-day regional stress conditions deduced from plate kinematics and tectonomorphology and suggest the emplacement of dykes along pre-existing fractures. The distinct timing and location of each dyke system likely results from a slight shift of the magmatic source.

Reconstructing the architectural evolution of volcanic islands from combined K/AR, morphologic, tectonic, and magnetic data. The Faial Island exemple (Azores)

The morpho-structural evolution of oceanic islands results from competition between volcano growth and partial destruction by mass-wasting processes. We present here a multi-disciplinary study of the successive stages of development of Faial (Azores) during the last 1 Myr. Using high-resolution digital elevation model (DEM), and new K/Ar, tectonic, and magnetic data, we reconstruct the rapidly evolving topography at successive stages, in response to complex interactions between volcanic construction and mass wasting, including the development of a graben. We show that: (1) sub-aerial evolution of the island first involved the rapid growth of a large elongated volcano at ca. 0.85 Ma, followed by its partial destruction over half a million years; (2) beginning about 360 ka a new small edifice grew on the NE of the island, and was subsequently cut by normal faults responsible for initiation of the graben; (3) after an apparent pause of ca. 250 kyr, the large Central Volcano (CV) developed on the western side of the island at ca 120 ka, accumulating a thick pile of lava flows in less than 20 kyr, which were partly channelized within the graben; (4) the period between 120 ka and 40 ka is marked by widespread deformation at the island scale, including westward propagation of faulting and associated erosion of the graben walls, which produced sedimentary deposits; subsequent growth of the CV at 40 ka was then constrained within the graben, with lava flowing onto the sediments up to the eastern shore; (5) the island evolution during the Holocene involves basaltic volcanic activity along the main southern faults and pyroclastic eruptions associated with the formation of a caldera volcano-tectonic depression. We conclude that the whole evolution of Faial Island has been characterized by successive short volcanic pulses probably controlled by brief episodes of regional deformation. Each pulse has been separated by considerable periods of volcanic inactivity during which the Faial graben gradually developed. We propose that the volume loss associated with sudden magma extraction from a shallow reservoir in different episodes triggered incremental downward graben movement, as observed historically, when immediate vertical collapse of up to 2 m was observed along the western segments of the graben at the end of the Capelinhos eruptive crises (1957-58).

Fractional electrical impedances in botanical elements

Fractional calculus (FC) is no longer considered solely from a mathematical viewpoint, and is now applied in many emerging scientific areas, such as electricity, magnetism, mechanics, fluid dynamics, and medicine. In the field of dynamical systems, significant work has been carried out proving the importance of fractional order mathematical models. This article studies the electrical impedance of vegetables and fruits from a FC perspective. From this line of thought, several experiments are developed for measuring the impedance of botanical elements. The results are analyzed using Bode and polar diagrams, which lead to electrical circuit models revealing fractional-order behaviour.

Low temperature structural transitions in dipolar hard spheres: the influence on magnetic properties

We investigate the structural chain-to-ring transition at low temperature in a gas of dipolar hard spheres (DRS). Due to the weakening of entropic contribution, ring formation becomes noticeable when the effective dipole-dipole magnetic interaction increases, It results in the redistribution of particles from usually observed flexible chains into flexible rings. The concentration (rho) of DI-IS plays a crucial part in this transition: at a very low rho only chains and rings are observed, whereas even a slight increase of the volume fraction leads to the formation of branched or defect structures. As a result, the fraction of DHS aggregated in defect-free rings turns out to be a non-monotonic function of rho. The average ring size is found to be a slower increasing function of rho when compared Lo that of chains. Both theory and computer simulations confirm the dramatic influence of the ring formation on the rho-dependence of the initial magnetic susceptibility (chi) when the temperature decreases. The rings clue to their zero total dipole moment are irresponsive to a weak magnetic field and drive to the strong decrease of the initial magnetic susceptibility. (C) 2014 Elsevier B.V. All rights reserved.

A cirurgia reconstrutiva em patologia oncológica do nariz : paralisia do nervo facial anatomia cirurgia do nariz

RESUMO: Os carcinomas localizados no nariz são muito frequentes em todas as séries conhecidas. São de diagnóstico clínico fácil e a sua confirmação por biópsia é muito segura. As terapêuticas mais indicadas são a cirurgia e a radioterapia, genericamente eficazes. Verifica-se, no entanto, que os pacientes continuam a solicitar tratamento em estádios muito avançados, mesmo conhecendo o diagnóstico e tendo acesso aos serviços sem custos. Esta situação poderá explicar-se face ao curso relativamente lento de muitos destes tumores e à idade geralmente avançada dos doentes que, de acordo com alguns inquéritos, receiam mais a terapeûtica do que a doença. Para obtenção de informação útil para condução deste problema, foram ainda analisados outros parâmetros. A maioria dos pacientes continua a solicitar tratamento quando as lesões envolvem duas subunidades nasais. Esta circunstância permite planear o tratamento cirúrgico com relativa facilidade, isto é, com exérese e reconstrução cujo resultado estético final é bastante aceitável. Os tumores de grandes dimensões, envolvendo várias subunidades, sendo frequentes, raramente implicam rinectomia total. Pelo contrário, são mais frequentes os tumores que envolvem metade do nariz e as estruturas vizinhas tais como o maxilar, a órbita e o lábio superior, atingindo mesmo a base do crânio. O controlo da doença nestes estádios é muito difícil. Não raramente, quando se crê que a doença está controlada, a cirurgia reconstrutiva bem como outras formas de reabilitação conjugadas, deixam ainda muita insatisfação. A nossa actividade tem-se desenvolvido seguindo os critérios adoptados nos melhores centros, isto é, as técnicas clássicas, complementadas com refinamentos recentes. Porém reflectindo sobre os resultados obtidos no tratamento de tumores do nariz, surge-nos um conjunto de questões para as quais ainda não encontrámos respostas cabais. Actuando de acordo com os princípios que definem o estado da arte, não obtivemos ainda resultados que satisfaçam tanto os doentes quanto os cirurgiões. Incessantemente procuramos novos dados técnicos e científicos que nos permitam sair deste ciclo vicioso em que o doente retarda a procura de assistência, receoso de que a terapêutica o deixe desfigurado. Tendo sempre em vista a obtenção dos melhores resultados com o mínimo de tempos cirúrgicos, valorizamos alguns detalhes praticados nos retalhos com padrão vascular bem definido. Dado que as sequelas na zona dadora de tecidos são uma incontornável preocupação, procuramos refinar a sua aplicação no sentido de as atenuarmos. A fronte, excelente zona dadora para reconstrucção nasal major, era sede de sequelas actualmente inaceitáveis. Estudado o comportamento dos tecidos na fronte, depois de levantado o retalho e efectuado o seu encerramento com uso da técnica de expansão intra-operatória, determinámos a presença do Factor de Crescimento Vascular Endotelial no próprio retalho e na zona dadora, tendo em vista que a sua presença poderá explicar o comportamento dos tecidos que foram submetidos a esta técnica. Procurou-se estudar a qualidade da reconstrução em 45 pacientes submetidos a cirurgia de exérese e reconstrução nasal major, assim como a qualidade de vida, relacionada com a doença e a terapêutica. Embora se possa admitir a existência de dados sugestivos de estratégias mais adequadas, não foi possível relacionar a qualidade da reconstrução com qualidade de vida dos pacientes. Poderá eventualmente concluir-se que a observação permanente da reconstrução, com qualidade estética e funcional, será o melhor método de alterar a ideia clássica, ainda muito divulgada, mas já ultrapassada, de que a cirurgia reconstrutiva do nariz não é mais que transformar um defeito horroroso num defeito ridículo.---------------ABSTRACT: Malignant tumours found in the nose are very frequent in all known series. Clinical diagnosis is simple and confirmation of biopsy diagnosis is accessible and safe. The most advisable therapies are surgery and radiotherapy. Despite everything patients continue to wait until the tumour is in an advanced stage before asking for therapy, although they know the diagnosis and have free access to specialised services. This situation could probably be explained by the slow development rate of the tumours which is associated with the age of the patient. Upon inquiry, it was found that a significant number of patients are more afraid of therapy than of the disease itself. Other parameters have been analysed in order to obtain useful information about the management of this problem. The majority of patients seek adequate treatment when the lesions involve two nasal subunits. This allows the programming of surgical therapy with relative ease as they may be removed and reconstructed with interesting final aesthetical results. Large tumours involving several subunits are frequent, but they rarely call for total rhinectomy. On the contrary, tumours more frequently involve half of the nose and their neighbouring structures: for example, maxillary, orbital and upper lip, even reaching as far as the base of the skull. The control of the disease is very difficult in these stages.In cases in which it is believed that the disease is under control, reconstructive surgery in conjunction with other forms of rehabilitation still result in a lot of dissatisfaction. In our activity we try to follow the criteria adopted by the best centres following classic techniques, complemented with recent refinements. Reflecting on the treatment of tumours of the nose has led us to a series of questions to which we haven’t yet found the answers. In accordance with the defined principles of ‘the state of the art’ it still doesn’t satisfy either the patients or the surgeons. We are looking for new technical and scientific data which allows us to leave this vicious cycle, in that the deferred patient avoids looking for assistance, based on the fear that therapy could leave them disfigured. We attach importance to some practiced details on the well-defined vascular pattern of the flaps, with the principle aim of obtaining a good result, from the minimum number of operations. It is known that sequels in donor sites are a concern, so applied refinements are used in order to reduce the defect. The forehead has been considered an excellent donor site for major nasal reconstruction but the area of sequel is nowadays unacceptable. We tried to study the behaviour of the tissues of the forehead after taking the flap and closing the wound, using the intraoperative expansion technique. We determined the presence of Vascular Endothelial Growth Factor in the flaps and in the donor site, in which its presence could explain the behaviour of the tissues of the forehead that are submitted to this technique. The quality of the reconstruction was studied in 45 patients who were submitted to surgical exeresisand major nasal reconstruction, as was the relationship between the disease and the therapy regarding quality of life. It was not possible to directely relate the quality of the reconstruction to the quality of patients life, although some suggestive data of more adequate manegement may be interesting. One might eventually conclude that, permanent exposure of the reconstruction with aesthetic and funcional quality would be the best method in order to modify the classic idea which is still known although overridden today, that nasal reconstruction could transform a horrible defect into a ridiculous one.-------RÉSUMÉ: Les carcinomes situés sur le nez sont très fréquents dans toutes les séries connues. Ils sont de diagnostic facile et la confirmation de ce dernier par une biopsie, est accessible et très fiable. La chirurgie et la radiothérapie sont les thérapeutiques les mieux indiquées. Toutefois les patients continuent de solliciter un traitement, seulement dans des états très avancés bien qu’ils aient eu connaissance du diagnostic et ayant accès aux services. Cette situation pourra probablement s’expliquer par l’évolution relativement indolente de beaucoup de tumeurs, associée à l’âge des malades; bien que selon quelques enquêtes réalisées un nombre élevé de malades craint davantage la thérapeutique que la maladie. D’autres paramètres sont analysés en vue d’obtenir des informations utiles pour l’accompagnement de ce problème. La majorité de nos patients sollicite le traitement adéquat quand les lésions entourent deux sous-unités nasales, ce qui permet de planifier le traitement chirurgique avec une certaine facilité, c’est à dire l’exérèse et la reconstruction ayant un résultat final esthétique généralement très acceptable. Les tumeurs de grandes dimensions entourant différentes sous-unités sont fréquentes mais elles impliquent rarement une amputation nasal total. Au contraire, les tumeurs les plus fréquentes sont celles qui entourent la moitié du nez et les structures voisines comme le maxillaire, l’orbite et la lèvre supérieure, parfois, elles peuvent même atteindre la base du crâne. Le contrôle de la maladie dans ces états est très difficile et quand nous pensons que la maladie est contrôlée, la chirurgie reconstructrice associée à d’autres formes de réhabilitation provoquent encore une grande insatisfaction. Nous exerçons notre activité en essayant de suivre les critères adoptés dans les meilleurs centres. Nous appliquons les techniques classiques complétées de retouches pour obtenir un meilleur resultat. Le fait de traiter les tumeurs nasales nous fait réfléchir et poser un ensemble de questions auxquelles nous n’avons pas pu trouver de réponses. En actuant en accord avec les principes qui définissent l’état de l’art, nous n’avons pas obtenu de résultats qui satisfassent les malades et les chirurgiens. Nous recherchons de nouvelles données techniques et scientifiques qui nous permettent de sortir de ce cercle vicieux dans lequel le patient retarde la recherche d’aide craignant que la thérapeutique le défigure. Nous valorisons certains détails pratiqués sur les lambeaux de patron vasculaire bien défini et ayant comme principaux objectifs l’obtention d’un bon résultat en moins de temps de chirurgie. Nous savons que les séquelles de la zone donneuse de tissus sont préoccupantes, ainsi, que les retouches qui ont été appliqués dans l’objectif de les atténuer. Le front, excellente zone donneuse pour la reconstruction nasale majeure, était une source de séquelle actuellement inacceptable. Nous avons étudié le comportement des tissus du front après avoir relevé le lambeau et effectué la fermeture avec la technique de l’expansion intraoperative. Nous avons déterminé la présence du Facteur de Croissance Vasculaire Endothéliale dans le propre lambeau et dans la zone donneuse, celle-ci pourra expliquer le comportement des tissus du front qui ont été soumis à cette technique. On a essayé d´etudier la qualité de la reconstruction sur 45 patients soumis à la chirurgie d´exérèse et la reconstruction nasal majeure, ainsi comme la qualité de vie en relation avec la maladie et la thérapie. Quoique l´on puisse conclure par l´existence des données subjectives des stratégies plus justes, il est impossible de faire un rapport sur la qualité de la reconstruction avec la qualité de vie des patients. Eventuellement l´on purrait conclure que l´observation permanente de la reconstruction avec qualité esthétique et fonctionnelle, se serait la meilleure méthod de changer l´idée classique, mais depassée, de que la rhinopoièse n´est pas que transformer un affreux défaut par un défaut ridicule.

First isolation of dengue 3 in Brazil from an imported case

The authors report the isolation of dengue 3 virus for the first time in Brazil. The patient, resident in Limeira-SP, traveled to Nicaragua on May 16th, 1998, where he stayed for two months. Starting on August 14th he had fever, headache, myalgia, arthralgia, retro-orbital pain and diarrhea. He returned to Brazil on August 16th and was hospitalized in the next day. The patient had full recovery and was discharged on August 20th. The virus was isolated in C6/36 cell culture inoculated with serum collected on the 6th day after the onset of the symptoms. The serotype 3 was identified by indirect immunofluorescence assays performed with type-specific monoclonal antibodies. This serotype was further confirmed by polymerase chain reaction analysis. The introduction of a new dengue serotype in a susceptible population is a real threat for the occurrence of severe forms of the disease. The isolation and identification of dengue virus are important in order to monitoring the serotypes circulating in Brazil and to take the measures necessary to prevent and control an epidemic.