986 resultados para ACTIVE AREAS
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Reconfigurable computing experienced a considerable expansion in the last few years, due in part to the fast run-time partial reconfiguration features offered by recent SRAM-based Field Programmable Gate Arrays (FPGAs), which allowed the implementation in real-time of dynamic resource allocation strategies, with multiple independent functions from different applications sharing the same logic resources in the space and temporal domains. However, when the sequence of reconfigurations to be performed is not predictable, the efficient management of the logic space available becomes the greatest challenge posed to these systems. Resource allocation decisions have to be made concurrently with system operation, taking into account function priorities and optimizing the space currently available. As a consequence of the unpredictability of this allocation procedure, the logic space becomes fragmented, with many small areas of free resources failing to satisfy most requests and so remaining unused. A rearrangement of the currently running functions is therefore necessary, so as to obtain enough contiguous space to implement incoming functions, avoiding the spreading of their components and the resulting degradation of system performance. A novel active relocation procedure for Configurable Logic Blocks (CLBs) is herein presented, able to carry out online rearrangements, defragmenting the available FPGA resources without disturbing functions currently running.
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This paper describes the environmental monitoring / regatta beacon buoy under development at the Laboratory of Autonomous Systems (LSA) of the Polytechnic Institute of Porto. On the one hand, environmentalmonitoring of open water bodies in real or deferred time is essential to assess and make sensible decisions and, on the other hand, the broadcast in real time of position, water and wind related parameters allows autonomous boats to optimise their regatta performance. This proposal, rather than restraining the boats autonomy, fosters the development of intelligent behaviour by allowing the boats to focus on regatta strategy and tactics. The Nautical and Telemetric Application (NAUTA) buoy is a dual mode reconfigurable system that includes communications, control, data logging, sensing, storage and power subsystems. In environmental monitoring mode, the buoy gathers and stores data from several underwater and above water sensors and, in regatta mode, the buoy becomes an active course mark for the autonomous sailing boats in the vicinity. During a race, the buoy broadcasts its position, together with the wind and the water current local conditions, allowing autonomous boats to navigate towards and round the mark successfully. This project started with the specification of the requirements of the dual mode operation, followed by the design and building of the buoy structure. The research is currently focussed on the development of the modular, reconfigurable, open source-based control system. The NAUTA buoy is innovative, extensible and optimises the on board platform resources.
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After a brief historical introduction, this paper deals with the main concerned geotectonic units: the Lower Tagus and Alvalade basins, the Western and Southern borders, and their infillings. Most of the Neogene events and record concern areas South of the Iberian Central Chain, a nearly inverse situation as that of Paleogene times. In the most important of these units, the Lower Tagus basin, there are quite thick detrital series, mostly marine in its distal part near Lisboa (albeit with several continental intercalations), and mainly continental in its inner part. Sedimentological record is almost complete since Lowermost to Upper Miocene. The richness ofdata (paleontology, isotope chronology, paleoclimate, etc.) it gives and the possibility of direct marine-continental correlations render this basin one of the more interesting ones in Western Europe. Alvalade basin is separated from the previous one by a barrier of Paleozoic rocks. Two transgressions events (Upper Tortonian and Messinian in age) are recorded. Active sedimentation may be correlated to Late Miocene tectonics events. In Algarve, chiefly marine units from Lower to Upper Miocene are well developped. The Lower unit (Lagos-Portimão Formation) is best exposed in Western Algarve, but desappears eastwards. Middle Miocene is not as well known, whereas Upper Miocene main outcrops are in Eastern Algarve. Cacela Formation is remarquable for its beautiful fossils. Sedimentation as a whole refletcts the tectonic activity and in special the evolution of the Algarve flexures. There is scant evidence of post-Lower Miocene volcanism, the latest known in Portugal. Pliocene has not been recognized there beyond doubt. Miocene sediments are much less important to the North of the Central Iberian Chain. Continental beds near Leiria that yielded the well-known "Hisp anotherium fauna" are lower Middle Miocene. Pliocene corresponds to dramatic changes in paleogeography. At Setiibal Peninsula there is some evidence of a minor Lower Pliocene transgression. Continental detrital sediments, often coarse, occupy rather large areas. In Western Portugal between the Setúbal Peninsula and Pombal there is good evidence of a marine Upper Pliocene transgression, followed up by dune sands overlain by marsh clays, diatomites, lignites and boghead levels that can be partly Pleistocene in age.
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It is very difficult to make paleoclimatic correlations between continental and marine areas, but it is possible with biostratigraphic data. Reliable correlations can be made only between broad periods: between 3.5 and 3 Ma, around 2.4 Ma, until 1.6 Ma and after 1.6 Ma. The arid Mediterranean phases led to the disappearance of the European Villafranchian fauna (1.0 Ma).
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Relatório de Estágio para obtenção do grau de Mestre em Engenharia na Área de Especializção em Edificações
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This paper addresses the estimation of surfaces from a set of 3D points using the unified framework described in [1]. This framework proposes the use of competitive learning for curve estimation, i.e., a set of points is defined on a deformable curve and they all compete to represent the available data. This paper extends the use of the unified framework to surface estimation. It o shown that competitive learning performes better than snakes, improving the model performance in the presence of concavities and allowing to desciminate close surfaces. The proposed model is evaluated in this paper using syntheticdata and medical images (MRI and ultrasound images).
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Hydatid disease in tropical areas poses a serious diagnostic problem due to the high frequence of cross-reactivity with other endemic helminthic infections. The enzyme-linked-immunosorbent assay (ELISA) and the double diffusion arc 5 showed respectively a sensitivity of 73% and 57% and a specificity of 84-95% and 100%. However, the specificity of ELISA was greatly increased by using ovine serum and phosphorylcholine in the diluent buffer. The hydatic antigen obtained from ovine cyst fluid showed three main protein bands of 64,58 and 30 KDa using SDS PAGE and immunoblotting. Sera from patients with onchocerciasis, cysticercosis, toxocariasis and Strongyloides infection cross-reacted with the 64 and 58 KDa bands by immunoblotting. However, none of the analyzed sera recognized the 30 KDa band, that seems to be specific in this assay. The immunoblotting showed a sensitivity of 80% and a specificity of 100% when used to recognize the 30 KDa band.
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Coupling five rigid or flexible bis(pyrazolato)based tectons with late transition metal ions allowed us to isolate 18 coordination polymers (CPs). As assessed by thermal analysis, all of them possess a remarkable thermal stability, their decomposition temperatures lying in the range of 340-500 degrees C. As demonstrated by N-2 adsorption measurements at 77 K, their Langmuir specific surface areas span the rather vast range of 135-1758 m(2)/g, in agreement with the porous or dense polymeric architectures retrieved by powder X-ray diffraction structure solution methods. Two representative families of CPs, built up with either rigid or flexible spacers, were tested as catalysts in (0 the microwave-assisted solvent-free peroxidative oxidation of alcohols by t-BuOOH, and (ii) the peroxidative oxidation of cydohexane to cydohexanol and cydohexanone by H2O2 in acetonitrile. Those CPs bearing the rigid spacer, concurrently possessing higher specific surface areas, are more active than the corresponding ones with the flexible spacer. Moreover, the two copper(I)-containing CPs investigated exhibit the highest efficiency in both reactions, leading selectively to a maximum product yield of 92% (and TON up to 1.5 x 10(3)) in the oxidation of 1-phenylethanol and of 11% in the oxidation of cydohexane, the latter value being higher than that granted by the current industrial process.
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A one-pot template reaction of sodium 2-(2-(dicyanomethylene) hydrazinyl) benzenesulfonate (NaHL1) with water and manganese(II) acetate tetrahydrate led to the mononuclear complex [Mn(H2O)(6)](HL1a)(2)center dot 4H(2)O (1), where (HL1a) -= 2-(SO3-)C6H4(NH)=N=C(C N) (CONH2) is the carboxamide species derived from nucleophilic attack of water on a cyano group of (HL1) . The copper tetramer [Cu-4(H2O)(10)(-) (1 kappa N: kappa O-2: kappa O, 2 kappa N: k(O)-L-2)(2)]center dot 2H(2)O (2) was obtained from reaction of Cu(NO3)(2)center dot 2.5H(2)O with sodium 5-(2( 4,4-dimethyl-2,6-dioxocyclohexylidene) hydrazinyl)-4-hydroxybenzene-1,3-disulfonate (Na2H2L2). Both complexes were characterized by elemental analysis, IR spectroscopy, ESI-MS and single crystal X-ray diffraction. They exhibit a high catalytic activity for the solvent-and additive-free microwave (MW) assisted oxidation of primary and secondary alcohols with tert-butylhydroperoxide, leading to yields of the oxidized products up to 85.5% and TOFs up to 1.90 x 103 h(-1) after 1 h under low power (5-10 W) MW irradiation. Moreover, the heterogeneous catalysts are easily recovered and reused, at least for three consecutive cycles, maintaining 89% of the initial activity and a high selectivity.
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Bancroftian filariasis is spreading in towns of endemic areas as in Recife, northeastern Brazil, where it is a major public health problem. This paper deals with the prevalence of microfilaraemia and filarial disease in two urban areas of Recife, studying their association with individual characteristics and variables related to the exposure to the vectors. The parasitologic survey was performed through a "door-to-door" census and microfilaraemia was examined by the thick-drop technique using 45µl of peripheral blood collected between 20:00 and 24:00 o' clock. 2,863 individuals aged between 5 and 65 years were interviewed and submitted to clinical examination. Males aged between 15 and 44 years old presented the greatest risk of being microfilaraemic. Microfilaraemia was also significantly associated with no use of bednet to sleep. The risk of being microfilaraemic was greater among those who had lived in the studied areas for more than 5 years. The overall disease prevalence was 6.3%. Males presented the greatest risk of developing acute disease. The risk of developing chronic manifestations was also greater among males and increased with age. We found no association between time of residence, bednet use, microfilaraemia and acute and chronic disease. We may conclude that in endemic areas there are subgroups of individuals who has a higher risk of being microfilariae carriers due to different behaviours in relation to vector contact.
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Plague caused by Yersinia pestis, has persisted in Brazil in several natural foci spread throughout rural areas in the States of Ceara, Paraiba, Pernambuco, Piaui, Rio Grande do Norte, Alagoas, Bahia, Minas Gerais and Rio de Janeiro. Nationwide surveillance of plague in Brazil based on serological testing started in 1983. We now present an update report of the examinations carried out in our laboratory from 1983 to 1992. The passive hemagglutination test for antibodies against fraction 1A antigen of Y. pestis and the passive hemagglutination inhibition control were employed for testing a total of 220,769 sera. Samples analyzed included 2,856 sera from clinically diagnosed plague cases or suspects, 49,848 sera from rodents of 24 species and 2 species of small wild carnivores (marsupials), 122,890 sera from dogs, and 45,175 sera from cats. Specific antibodies were found in 92 (3.22%) human sera; 143 (0.29%) sera from rodents of 8 species and from the two species of marsupials, 1,105 (0.90%) sera from dogs and 290 (0.64%) sera from cats. The presence of significant levels of specific anti-F1A antibodies among rodents and wild or domestic carnivores (dogs and cats) indicates that all the Brazilian plague foci remain active in spite of the absence of human cases in some of them.
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RESUMO: O objectivo deste trabalho foi avaliar se a exposição crónica neonatal à hiperóxia mo-derada induz alterações funcionais e estruturais persistentes nas vias aéreas. Desenvolveu-se um modelo animal, no rato, a partir do qual se retiraram implicações para a compreensão das repercussões crónicas da hiperóxia neonatal sobre as vias aéreas de displasia broncopulmonar (DBP), em duas fases distintas: imediatamente após a exposi-ção neonatal a 50%O2 (grupo 50%O2) e após três semanas de recuperação em ar ambiente (grupo 50%O2+Ar).Compararam-se os resultados da resposta do músculo liso de traqueia (MLT) à esti-mulação in vitro com metacolina e salbutamol e avaliaram-se as alterações quantitativas da área de MLT, bem como as alterações qualitativas da estrutura da traqueia. Demonstrou-se que a exposição a 50% de oxigénio não tinha repercussões imediatas sobre a resposta in vitro do MLT à estimulação colinérgica, mas que induzia um aumento do relaxamento em resposta ao salbutamol. A contractilidade do MLT em resposta à estimula-ção com metacolina no grupo 50%O2+Ar foi significativamente superior à do grupo de con-trolo da mesma idade e também superior à observada no grupo 50%O2, enquanto que a resposta ao salbutamol se voltou a aproximar dos valores de controlo após a recuperação em normóxia. Não se observaram diferenças estatisticamente significativas na área de MLT entre os grupos experimental e de controlo, o que se deve provavelmente ao número reduzido de amostras avaliadas e à variabilidade deste parâmetro no grupo de controlo; contudo, verifi-cou-se um aumento médio de 15% imediatamente após a exposição à hiperóxia que persis-tiu após o período de recuperação.As alterações qualitativas sobre a arquitectura da traqueia, avaliadas por microscopia óptica, revelaram no grupo 50%O2 aumentos da espessura da matriz extracelular e da den-sidade de mastócitos desgranulados na submucosa e adventícia vizinhas do MLT, sem outras alterações relativamente ao grupo de controlo com 15 dias. As alterações da matriz extrace-lular foram reversíveis após a recuperação em ar ambiente. A densidade de mastócitos per-maneceu superior à do grupo de controlo de 36 dias de idade, apresentando-se em maior contiguidade com o MLT relativamente ao grupo 50%O2. Em síntese, demonstrou-se que a hiperóxia neonatal crónica em níveis moderados in-duz alterações da resposta contráctil do MLT e da estrutura da traqueia que podem ter ex-pressão funcional após a exposição ter cessado. Assim, o contributo original do presente trabalho foi o desenvolvimento de um modelo animal que permite avaliar os mecanismos pelos quais a hiperóxia é capaz de induzir, isoladamente, alterações crónicas da contracti-lidade, do relaxamento do ML e da estrutura das vias aéreas que podem ser responsáveis pela HRB persistente em doentes sujeitos a oxigenioterapia neonatal.-------------ABSTRACT: The aim of this work was to evaluate whether chronic neonatal exposure to hyperoxia in-duces persistent structural and functional airway changes. An animal model was developed, using neonatal rats, in order to understand the chronic effects of neonatal hyperoxia on the airways, in bronchopulmonary dysplasia, in two distinct phases: immediately after neonatal exposure to 50%O2 (50%O2 group) and after three weeks of recovery at ambient air (50%O2+Ar group).The results from the tracheal smooth muscle (TSM) response to in vitro stimulation with metacholine and salbutamol were compared and quantitative changes in TSM area, as well as qualitative changes in tracheal structure were evaluated. It was demonstrated that while exposure to 50% oxygen had no immediate effects on in vitro TSM response to cholinergic stimulation, it induced an increase in relaxation as a result of salbutamol administration. TSM contractility as a result of methacholine administration in the 50%O2 + Ar group was significantly higher than that of the same-age control group, and also higher than the one observed in the 50%O2 group, whereas the response to salbutamol admini-stration was once again closer to the control values after recovery in normoxia. There were no statistically significant differences in the TSM area between the experi-mental and control groups, which is most likely due to the reduced number of samples evalu-ated and to the variability of this parameter in the control group. However, there was an aver-age increase of 15% immediately after exposure to hyperoxia, which persisted after the recov-ery period. Qualitative changes in tracheal architecture, evaluated by optic microscopy, revealed that the 50%O2 group suffered an increase in the thickness of the extracellular matrix and degranu-lated mast cell density in the submucosa and adventitia adjacent to the TSM, without further changes when compared with the control group at 15 days of age. The changes in extracellular matrix were reversible after recovery in ambient air. Mast cell density remained higher than that of the control group at 36 days of age, and more contiguous to TSM than the 50%O2 group. In conclusion, it has been demonstrated that moderate levels of chronic neonatal hyperoxia in-duce changes in TSM contractile response and tracheal structure, which may be functionally ex-pressed after discontinuation of exposure. Therefore, the original contribution of the present work was the development of an animal model which allows the evaluation of the mechanisms through which hyperoxia alone can induce chronic changes in contractility and relaxation of SM and also in airway structure that can be responsible for the persistent airway hyperrespon-siveness found in patients who were submited to neonatal oxygen therapy.