999 resultados para 7038-212
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The use of multicores is becoming widespread inthe field of embedded systems, many of which have real-time requirements. Hence, ensuring that real-time applications meet their timing constraints is a pre-requisite before deploying them on these systems. This necessitates the consideration of the impact of the contention due to shared lowlevel hardware resources like the front-side bus (FSB) on the Worst-CaseExecution Time (WCET) of the tasks. Towards this aim, this paper proposes a method to determine an upper bound on the number of bus requests that tasks executing on a core can generate in a given time interval. We show that our method yields tighter upper bounds in comparison with the state of-the-art. We then apply our method to compute the extra contention delay incurred by tasks, when they are co-scheduled on different cores and access the shared main memory, using a shared bus, access to which is granted using a round-robin arbitration (RR) protocol.
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Unstabilized rammed earth is a recyclable, economical, and eco-friendly building material, used in the past and still applied today. Traditionally, its use was based on a long empirical knowledge of the local materials. Because this knowledge was mostly lost or is no longer sufficient, in many countries normative documents have been produced to allow the assessment of rammed earth soils. With the aim of contributing for a refining of these normative requirements, this article presents a research work that included: (i) collection of Unstabilized rammed earth samples from six constructions in Portugal; (ii) a literature survey of normative and complementary documents to identify the most mentioned key-properties, the test procedures and the corresponding threshold limits; and (iii) a discussion of the test procedures and of the thresholds limits in the light of the experimental results. The analyzed properties are the particle size distribution, maximum particle size, plasticity, compaction, linear shrinkage, organic content, and salt content. The work highlights the advantages of taking into account the characteristics of existing constructions as a basis for the establishment and further refining of consistent threshold values. In particular, it shows that it is essential to adjust the requirements to the specificities of local materials.
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Certain materials used and produced in a wide range of non-nuclear industries contain enhanced activity concentrations of natural radionuclides. In particular, electricity production from coal is one of the major sources of increased human exposure to naturally occurring radioactive materials. A methodology was developed to assess the radiological impact due to natural radiation background. The developed research was applied to a specific case study, the Sines coal-fired power plant, located in the southwest coastline of Portugal. Gamma radiation measurements were carried out with two different instruments: a sodium iodide scintillation detector counter (SPP2 NF, Saphymo) and a gamma ray spectrometer with energy discrimination (Falcon 5000, Canberra). Two circular survey areas were defined within 20 km of the power plant. Forty relevant measurements points were established within the sampling area: 15 urban and 25 suburban locations. Additionally, ten more measurements points were defined, mostly at the 20-km area. The registered gamma radiation varies from 20 to 98.33 counts per seconds (c.p.s.) corresponding to an external gamma exposure rate variable between 87.70 and 431.19 nGy/h. The highest values were measured at locations near the power plant and those located in an area within the 6 and 20 km from the stacks. In situ gamma radiation measurements with energy discrimination identified natural emitting nuclides as well as their decay products (Pb-212, Pb-2142, Ra-226, Th-232, Ac-228, Th-234, Pa-234, U- 235, etc.). According to the results, an influence from the stacks emissions has been identified both qualitatively and quantitatively. The developed methodology accomplished the lack of data in what concerns to radiation rate in the vicinity of Sines coal-fired power plant and consequently the resulting exposure to the nearby population.
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This paper proposes an implementation, based on a multi-agent system, of a management system for automated negotiation of electricity allocation for charging electric vehicles (EVs) and simulates its performance. The widespread existence of charging infrastructures capable of autonomous operation is recognised as a major driver towards the mass adoption of EVs by mobility consumers. Eventually, conflicting requirements from both power grid and EV owners require automated middleman aggregator agents to intermediate all operations, for example, bidding and negotiation, between these parts. Multi-agent systems are designed to provide distributed, modular, coordinated and collaborative management systems; therefore, they seem suitable to address the management of such complex charging infrastructures. Our solution consists in the implementation of virtual agents to be integrated into the management software of a charging infrastructure. We start by modelling the multi-agent architecture using a federated, hierarchical layers setup and as well as the agents' behaviours and interactions. Each of these layers comprises several components, for example, data bases, decision-making and auction mechanisms. The implementation of multi-agent platform and auctions rules, and of models for battery dynamics, is also addressed. Four scenarios were predefined to assess the management system performance under real usage conditions, considering different types of profiles for EVs owners', different infrastructure configurations and usage and different loads on the utility grid (where real data from the concession holder of the Portuguese electricity transmission grid is used). Simulations carried with the four scenarios validate the performance of the modelled system while complying with all the requirements. Although all of these have been performed for one charging station alone, a multi-agent design may in the future be used for the higher level problem of distributing energy among charging stations. Copyright (c) 2014 John Wiley & Sons, Ltd.
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Experimental Chagas' disease (45 to 90 days post-infection) showed serious cardiac alterations in the contractility and in the pharmacological response to beta adrenergic receptors in normal and T. cruzi infected mice (post-acute phase). Chagasic infection did not change the beta receptors density (78.591 ± 3.125 fmol/mg protein and 73.647 ± 2.194 fmol/mg protein for controls) but their affinity was significantly diminished (Kd = 7.299 ± 0.426 nM and Kd = 3.759 ± 0.212 nM for the control) p < 0.001. This results demonstrate that the alterations in pharmacological response previously reported in chagasic myocardium are related to a significantly less beta cardiac receptor affinity. During this experimental period serious cardiac cell alterations take place and functional consequences will be detected in the chronic phase.
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To investigate the possible role of domestic animals as reservoirs of human enteroviruses, we studied 212 stray dogs captured in different areas of the municipality of São Paulo. The captured animals were divided into 19 groups of 10 to 20 dogs each; faeces of 126 of the 212 dogs were processed for enterovirus isolation. The following viruses were isolated from 12 dogs: poliovirus type 1 (2 dogs), poliovirus type 3 (1 dog), echovirus type 7 (8 dogs) and echovirus type 15 (1 dog). Of the 12 infected animals, four had specific homotypic neutralizing antibody titres > 16. All 212 animals were tested for the presence of neutralizing antibodies to human enteroviruses. The frequency of neutralizing antibodies present in titres of > 16 was 10.3%, 3,8% and 4.3% for vaccinal prototypes of polioviruses 1, 2 and 3 respectively; 1,9%, 1.4% and 1.5% for wild prototypes of the same viruses, 11.3% for echovirus 7, and 2.4% for echovirus 15. The proportion of dogs with neutralizing antibodies varied with the virus studied. Some indication of the susceptibility of dogs to infection with human enteroviruses was demonstrated, and the importance of this fact for the Plan for Global Eradication of the Wild Poliovirus is discussed.
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Background Iron is vital for almost all living organisms by participating in a wide range of metabolic processes. However, iron concentration in body tissues must be tightly regulated since excessive iron may lead to microbial infections or cause tissue damage. Disorders of iron metabolism are among the most common human diseases and cover several conditions with varied clinical manifestations. Methods An extensive literature review on the basic aspects of iron metabolism was performed, and the most recent findings on this field were highlighted as well. Results New insights on iron metabolism have shed light into its real complexity, and its role in both healthy and pathological states has been recognized. Important discoveries about the iron regulatory machine and imbalances in its regulation have been made, which may lead in a near future to the development of new therapeutic strategies against iron disorders. Besides, the toxicity of free iron and its association with several pathologies has been addressed, although it requires further investigations. Conclusion This review will provide students in the fields of biochemistry and health sciences a brief and clear overview of iron physiology and toxicity, as well as imbalances in the iron homeostasis and associated pathological conditions.
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Four rabies antigen batches were produced from virus suspensions resulting from BHK21 cells adhered to microcarriers (Cytodex 1), inoculated and cultured in a bioreactor. In parallel the methodology of production of rabies virus through cultures of BHK21 cells in monolayers in bottles was used. The results obtained showed that infecting titles were 106.69 DL50/mL and 107.28 DL50/mL for suspensions cultured in bottles and in the bioreactor, respectively. The viral suspension volumes collected were on average 11,900 per batch from the bioreactor and 800mL per bottle. Ten horses were immunized with the antigen produced in the bioreactor. The means of antirabies antibody titers found were 240 and 212 IU/mL after the initial and the first booster doses, respectively. Rabies antigen with satisfactory infecting titers can be obtained on a large scale by culturing in a bioreactor inoculated BHK21 cells adhered to microcarriers.
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Dissertação para obtenção do grau de Mestre em Engenharia Química e Bioquímica
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For uniformly asymptotically affine (uaa) Markov maps on train tracks, we prove the following type of rigidity result: if a topological conjugacy between them is (uaa) at a point in the train track then the conjugacy is (uaa) everywhere. In particular, our methods apply to the case in which the domains of the Markov maps are Canter sets. We also present similar statements for (uaa:) and C-r Markov families. These results generalize the similar ones of Sullivan and de Faria for C-r expanding circle maps with r > 1 and have useful applications to hyperbolic dynamics on surfaces and laminations.
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O laringocelo é uma dilatação anómala do sáculo ventricular, com comunicação com o lúmen laríngeo. Pode ser congénito ou adquirido, sendo a etiopatogénese do tipo adquirido multifactorial. O laringocelo adquirido pode estar relacionado com um aumento prolongado da pressão intralaríngea. Manifesta-se sobretudo em indivíduos do sexo masculino, caucasianos, na quinta ou sexta décadas de vida; é mais frequentemente unilateral e do tipo combinado ou misto. Habitualmente a sua evolução é lenta; no entanto, a sua forma de apresentação pode ser súbita, com dispneia laríngea que pode requerer intubação orotraqueal ou uma traqueotomia de urgência, como no caso da sobreinfecção, com formação de um laringopiocelo. Apresentamos o caso clínico de uma doente do sexo feminino, de 71 anos de idade, vendedora de flores na rua, que dá entrada na Urgência do Hospital de S. José por odinofagia e disfonia com um mês e meio de evolução e que, na sequência de primeira toma de antibiótico, tem reacção alérgica com necessidade de internamento por Otorrinolaringologia. A ulterior investigação revelou laringopiocelo misto. O laringocelo é uma patologia rara e que raramente se apresenta sob a forma de obstrução da via aérea. A sua sobreinfecção ocorre em apenas 8% dos casos, o que torna este caso clínico particularmente raro. No entanto consideramos importante ter em mente esta patologia no diagnóstico diferencial da obstrução aguda da via aérea superior.
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Dissertação para obtenção do Grau de Mestre em Engenharia Informática
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A obesidade mórbida (OM) é uma versão patológica de obesidade considerada um grave problema de saúde para os indivíduos que dela sofrem. O seu tratamento deve ser baseado numa abordagem biopsicossocial do indivíduo e do seu processo de doença que assegure o êxito do tratamento, a curto e longo prazo. A abordagem psicológica de cariz cognitivocomportamental estrutura-se ao longo das 3 principais fases do processo de tratamento: (1) pré-cirurgia, (2) internamento e (3) pós-cirurgia e follow-up. A primeira fase desta abordagem corresponde à avaliação psicológica dos doentes candidatos a cirurgia. Neste estudo apresenta-se a caracterização psicológica da população com OM, avaliada entre Fevereiro de 2002 e Maio de 2004, duma consulta de especialidade hospitalar. A metodologia desenvolvida inclui uma entrevista clínica semi-estruturada e questionários de auto-avaliação das dimensões de personalidade (MCMI-II), ansiedade e depressão (HADS), qualidade de vida (MOS-SF/20) e auto-conceito (ICAC). Foram avaliados 212 pacientes com uma média de idades de 41,1 anos e um IMC de 46,6Kg/m2. Apresentam-se os resultados obtidos e o protocolo de avaliação psicológica desenvolvido. Salienta-se a importância da avaliação psicológica para parecer técnico e os seus dados qualitativos para delineamento dos objectivos psicoterapêuticos e psico-educativos, como modo imprescindível ao sucesso deste processo de tratamento.
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As lesões metastáticas extradurais são o tipo de tumor mais frequente a nível dos diferentes segmentos da coluna. Entre Janeiro de 1989 e Junho de 1996, foram observados a nível hospitalar 209 doentes com metástases da coluna. Com base num protocolo de avaliação individual, foi efectuado um estudo retrospectivo destes doentes, incidindo primordialmente sobre o respectivo quadro clínico e alterações neuro-imagiológicas encontradas, bem como sobre o tipo de neoplasia primária e a resposta à terapêutica instituída. Tivemos como objectivo fundamental o de tentar caracterizar a semiologia e evolução mais habituais deste tipo de lesões, no sentido da obtenção dum diagnóstico rápido e da instituição duma terapêutica em tempo útil, permitindo um índice de sobrevida com o mínimo de qualidade.
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Introduction: Paediatric patients who undergo posterior spinal fusion surgery to correct scoliosis often require multiple blood transfusions. Tranexamic acid is a synthetic antifibrinolytic drug that reduces transfusion requirements in scoliosis surgery (1),(2),(3). Methods: To evaluate the efficacy of prophylactic tranexamic acid (TA) (initial dose of 10mg/kg and infusion of 1mg.kg(-1).h(-1)) in reducing perioperative blood transfusion requirements, we reviewed patients files and compared the amount of blood lost and blood transfused in the perioperative period of 12 patients (54.5%) that received TA and 10 patients (45.5%) who did not received TA. T-Student test was applied. Results: The average difference of blood losses (2,67 +/- 6,06ml) and blood transfused (212,9 +/- 101,1ml) between the two groups was not statistically significant (p>0.05). No thrombotic complications were detected in either group. Discussion: Results of the current study showed that prophylactic low dose of TA did not have a significant effect in the management of intraoperative blood loss and transfusion requirements in children undergoing scoliosis surgery. It is important to emphasize that our study is retrospective and that the size of the sample is small. Further studies are needed to evaluate the efficacy and safety of TA on paediatric scoliosis surgery.