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Dielectric barrier discharge plasma actuators have recently become desirable devices for simultaneous flow control and ice mitigation applications, with particular interest in wind turbines operating in cold climates. Considering the potential of plasma actuators for these specific applications, it is necessary to deeply understand the thermal effects generated by the plasma-induced flow to proceed with further optimizations. However, due to the local high electric field and high electromagnetic interference generated, there is a lack of experimental studies on the topic. The current work implements an in-house experimental technique based on the background-oriented schlieren principle for plasma-induced flow thermal characterization. Since this technique is based on optical measurements, it is not affected by the electromagnetic interference issues caused by the plasma discharge. A detailed experimental analysis is performed on a conventional Kapton actuator exploiting the relation between the actuator surface temperature and the induced thermal flow. The influence of the input voltage and the transient plasma-induced flow thermal behavior is analyzed. The results demonstrate that plasma actuators are fast response time devices that can heat the adjacent medium in less than a second after starting the operation.

Cold climate regions have great potential for wind power generation. The available wind energy in these regions is about 10% higher than in other regions due to higher wind speeds and increased air density. However, these regions usually have favorable icing conditions that lead to ice accumulation on the wind turbine blades, which in turn increases the weight of the blades and disrupts local airflow, resulting in a reduction in wind turbine performance. Considering this problem, plasma actuators have been proposed as devices for simultaneous flow control and deicing. These devices transfer momentum to the local airflow, improving the aerodynamic performances of the turbine blades while producing significant thermal effects that can be used to prevent ice formation. Considering the potential application of plasma actuators for simultaneous flow control and deicing, it is very important to investigate the thermal effects induced by these devices. However, due to the significant electromagnetic interference generated by the operation of these devices, there is a lack of experimental techniques that can be used to analyze them. In the current work, a background-oriented Schlieren system was developed and is presented as a new experimental technique for the thermal characterization of the plasma-induced flow. For the first time, the induced flow temperatures are characterized for plasma actuators with different dielectric materials and different dielectric thicknesses. The results demonstrate that, due to the plasma discharge, the temperature of the plasma-induced flow increases with the increase of the applied voltage and may achieve temperatures five times higher than the room temperature, which proves the potential of plasma actuators for deicing applications. The results are presented and discussed with respect to the potential application of plasma actuators for simultaneous flow control and deicing of wind turbine blades.

Ice accretion is a common issue on aircraft flying in cold climate conditions. The ice accumulation on aircraft surfaces disturbs the adjacent airflow field, increases the drag, and significantly reduces the aircraft’s aerodynamic performance. It also increases the weight of the aircraft and causes the failure of critical components in some situations, leading to premature aerodynamic stall and loss of control and lift. With this in mind, several authors have begun to study the thermal effects of plasma actuators for icing control and mitigation, considering both aeronautical and wind energy applications. Although this is a recent topic, several studies have already been performed, and it is clear this topic has attracted the attention of several research groups. Considering the importance and potential of using dielectric barrier discharge (DBD) plasma actuators for ice mitigation, we aim to present in this paper the first review on this topic, summarizing all the information reported in the literature about three major subtopics: thermal effects induced by DBD plasma actuators, plasma actuators’ ability in deicing and ice formation prevention, and ice detection capability of DBD plasma actuators. An overview of the characteristics of these devices is performed and conclusions are drawn regarding recent developments in the application of plasma actuators for icing mitigation purposes.

No período de 1976 a 1990, 14 pacientes com tumor de células transicionais do trato urinário superior foram tratados no Serviço de Urologia do Hospital Oncológico Amaral Carvalho. Destes tumores, sete foram encontrados na pelve renal e sete em ureter distal. O tratamento de escolha para esses tumores foi a nefroureterectomia, com retirada de cone vesical, perimeatal. Em um caso de tumor de ureter, com baixo grau e estadiamento, foi realizada ureterectomia segmentar.

No período de 1976 a 1989, 46 pacientes com hipernefroma foram tratados no Serviço de Urologia do Hospital Amaral Carvalho. Esses pacientes foram divididos segundo o estadiamento do tumor e foram estudados em relação ao sexo, idade, cor, lado afetado e conduta do serviço, nesses 13 anos. Foi realizado levantamento da literatura mundial a respeito das condutas atuais nesses tumores.

Modeling Coandã effect has been a fundamental issue in fluid dynamic research in the XX century. It has lost some interest because of the improvement in CFD, even if it could be still important in the area of the preliminary design of aerodynamic devices that benefits of fluid deflection by convex surfaces. An effective model of Coandã effect has not been defined, and fundamental questions are still open. The influence of convective heat exchange on Coandã adhesion of a fluid stream on a convex surface in the presence of a temperature gradient between the fluid and the convex surface is a problem, which affects many practical cases, but it is still marginally approached by scientific literature. This paper aims to start an effective research direction on the effects of convective heat exchange on Coandã effect. It approaches the problem with a set of CFD simulations. It analyses the previous hypotheses, which are based on Prandtl number and evidences the need of a more effective model that accounts also for the Reynolds number.

Two fundamental questions are still open about the complex relation between fluid dynamics and thermodynamics. Is it possible (and convenient) to describe fluid dynamic in terms of second law based thermodynamic equations? Is it possible to solve and manage fluid dynamics problems by mean of second law of thermodynamics? This chapter analyses the problem of the relationships between the laws of fluid dynamics and thermodynamics in both first and second law of thermodynamics in the light of constructal law. In particular, taking into account constructal law and the diffusive formulation of Bejan number, it defines a preliminary step through an extensive thermodynamic vision of fluid dynamic phenomena.

Introdução: A utilização de instrumentos de medida padronizados e fidedignos é um pré-requisito das boas práticas da Fisioterapia e permite monitorizar os resultados da intervenção e reclamar credibilidade científica para a profissão. A Stroke Rehabilitation Assessment of Movement (STREAM) é um instrumento muito utilizado na avaliação das limitações a nível do movimento voluntário e da mobilidade básica em utentes com sequelas de Acidente Vascular Cerebral (AVC). Objetivo: Contribuir para a adaptação transcultural e validação da versão portuguesa da STREAM, ao contexto cultural e linguístico Moçambicano. Materiais e Métodos: Foram utilizadas duas amostras distintas: 1) 9 peritos analisaram a validade de conteúdo; 2) 70 utentes com sequelas de AVC selecionados por conveniência do Hospital Central de Nampula (HCN) e do Hospital Geral de Mavalane (HGM), foram submetidos à aplicação da escala STREAM por 6 observadores independentes, com a finalidade de analisar a fiabilidade do instrumento. Resultados: A versão Moçambicana da STREAM, revelou para a validade de conteúdo, um consenso absoluto (100%) entre os elementos do painel de peritos; para a reprodutibilidade inter-observador, os valores do Coeficiente de Correlação Intraclasse (CCI) indicaram um índice de concordância perfeita, com valores de CCI que variaram entre 0,980-0,993 no HCN e entre 0,980-1,000 no HGM e, uma boa consistência interna com valores de alfa de Cronbach entre 0,904-0,998 no HCN e entre 0,881-1,000 no HGM, para cada uma das 3 subescalas e para o total da escala. Conclusão: A versão Moçambicana da escala STREAM revelou ser válida e fiável para as propriedades psicométricas investigadas (...)

Intramural hematoma of the colon is very rare, particularly when associated with the development of autoantibodies against factor VIII. We report a case of a 66-year-old man with abdominal pain, hematochezia and clots in the left colon, without any radiologic signs of active bleeding or bowel occlusion or analytical changes in routine coagulation screening, but with positive autoantibodies against factor VIII. The clinical instability prompted surgical exploration. An intramural hematoma of the left colon was found, and a left colectomy was performed. The patient was treated with hemoderivatives and corticosteroids with clinical improvement. The diagnosis of spontaneous intramural hematoma might be a challenge, particularly in the absence of clinical suspicion. An early recognition is essential for a positive outcome. This case highlights a rare cause of bleeding and intestinal obstruction, but also the difficulty and relevance of establishing a clinical diagnosis when diagnostic tests are not completely informative.

The introduction of the subject quality, according to the market needs opens space for the discussion of the quality as personal need, and also for the professional citizen's formation, besides introducing specific subjects of administration of companies. In that way, an optional discipline was offered for the students of the Chemistry Institute, approaching the theme "Quality and Administration of the Quality ", by three followed years. Of the general evaluation of the course it was extracted that it should always be accomplished, that the theme is current and important and it contributes to the personal/professional formation. With relationship to the compromising with the degree course, about of the students' half it assumes your compromising with the studies and the remaining ones say they are only involved. It is ended, therefore that the course reached your proposed objectives, it introduced the principal quality concepts according to the norms of the quality of the series ISO 9000 and it raised the discussion of the student's professional - citizen formation.

This paper continues recent research of the authors about the ACHEON Coanda effect two streams nozzle. This nozzle aims to produce an effective deflection of a propulsive jet with a correspondent deviation of the thrust vector in a 2D plane. On the basis of a previously published mathematical model, based on integral equations, it tries to produce an effective design guideline, which can be adopted for design activities of the nozzle for aeronautic propulsion. The presented model allows defining a governing method for this innovative two stream synthetic jet nozzle. The uncertainness level of the model are discussed and novel aircraft architectures based on it are presented. A CFD validation campaign is produced focusing on validating the model and the designs produced.

São descritas as manifestações clinicas, laboratoriais e aspectos evolutivos de cinco pacientes procedentes de Codajás-Amazonas, atendidos no Instituto de Medicina Tropical de Manaus devido ao quadro de hepatopatia grave, com período médio de doença de quatro dias. Quatro destes pacientes evoluiram para óbito, com uma média de cinco dias desde o inicio dos pródromos. A sorologia para hepatite B mostrou que o Ag HBs estava presente em quatro e o Anti - HBc em todos. Dos pacientes que foram ao óbito, através da necropsia a histopatologia do fígado revelou quadro de hepatite fulminante em dois e de febre de Lábrea nos outros dois.We have described the clinical and laboratory manifestations and evolutiortal aspects of five patients from Codajás, state of Amazonas, Brasil. These patients were treated at the Instituto de Medicina Tropical de Manaus with a picture of acute liver failure with an average period of evolution of 4 days. Of these patients, four died, within an average time of five days since the prodromal phase. Serology for hepatitis B showed that HBAg was present in four, and the HBc antigen in all patients. An autopsy was perfomed on the four patients who died, and the liver histopathology revealed a picture of fulminant hepatitis in two, and Lábrea fever (febre negra), in the other two.