967 resultados para Natural-rubber
Resumo:
Oysters are edible organisms that are often ingested partially cooked or even raw, presenting therefore a very high risk to the consumers' health, especially in tropical regions. The presence of Vibrio cholerae and Vibrio parahaemolyticus in oysters sampled at an estuary in the Brazilian northeastern region was studied, with 300 oysters tested through an 8-months period. The salinity of the water at the sampling point varied between 3% and 27. V. cholerae was the most frequently detected species (33.3% of the samples), and of the 22 V. cholerae isolates, 20 were identified as non-O1/non-O139, with two of the colonies presenting a rough surface and most of remaining ones belonging to the Heiberg II fermentation group. V. parahaemolyticus was isolated from just one of the samples. Other bacteria such as Providencia spp., Klebsiella spp. and Morganella morganii were also isolated.
Resumo:
Catastrophic events, such as wars and terrorist attacks, big tornadoes and hurricanes, huge earthquakes, tsunamis, floods, and landslides, are always accompanied by a large number of casualties. The size distribution of these casualties have separately been shown to follow approximate power law (PL) distributions. In this paper, we analyze the number of victims of catastrophic phenomena, in particular, terrorism, and find double PL behavior. This means that the data set is better approximated by two PLs instead of one. We have plotted the two PL parameters corresponding to all terrorist events occurred in every year, from 1980 to 2010. We observe an interesting pattern in the chart, where the lines, that connect each pair of points defining the double PLs, are roughly aligned to each other.
Resumo:
Dissertação para obtenção do Grau de Mestre em Engenharia e Gestão Industrial
Resumo:
The var genes of Plasmodium falciparum code for the antigenically variant erythrocyte membrane proteins 1 (PfEMP1), a major factor for cytoadherence and immune escape of the parasite. Herein, we analyzed the var gene transcript turnover in two ongoing, non-symptomatic infections at sequential time points during two weeks. The number of different circulating genomes was estimated by microsatellite analyses. In both infections, we observed a rapid turnover of plasmodial genotypes and var transcripts. The rapidly changing repertoire of var transcripts could have been caused either by swift elimination of circulating var-transcribing parasites stemming from different or identical genetic backgrounds, or by accelerated switching of var gene transcription itself.
Resumo:
Dissertação para obtenção do Grau de Mestre em Engenharia do Ambiente, perfil de Gestão e Sistemas Ambientais
Resumo:
This paper studies periodic gaits of multi-legged locomotion systems based on dynamic models. The purpose is to determine the system performance during walking and the best set of locomotion variables. For that objective the prescribed motion of the robot is completely characterized in terms of several locomotion variables such as gait, duty factor, body height, step length, stroke pitch, foot clearance, legs link lengths, foot-hip offset, body and legs mass and cycle time. In this perspective, we formulate three performance measures of the walking robot namely, the mean absolute energy, the mean power dispersion and the mean power lost in the joint actuators per walking distance. A set of model-based experiments reveals the influence of the locomotion variables in the proposed indices.
Resumo:
Proceeding of the 3rd International Conference on Fractional Systems and Signals, at Ghent, Belgium
Resumo:
Dissertação apresentada para cumprimento dos requisitos necessários à obtenção do grau de Mestre em Gestão do Território
Resumo:
Between April and October 2002, thirty fortnightly collections of oysters (Crassostrea rhizophorea) from a natural oyster bed at the Cocó River estuary in the Sabiaguaba region (Fortaleza, Ceará, Brazil) were carried out, aiming to isolate Aeromonas spp. strains. Oyster samples were submitted to the direct plating (DP) and the presence/absence (P/A) methods. Aeromonas were identified in 15 (50%) samples analyzed by the DP method and in 13 (43%) analyzed by the P/A method. A. caviae, A. eucrenophila, A. media, A. sobria, A. trota, A. veronii bv. sobria, A. veronii bv. veronii and Aeromonas sp. were isolated. The predominant species was A. veronii (both biovars), which was identified in 13 (43%) samples, followed by A. media in 11 (37%) and A. caviae in seven (23%). From the 59 strains identified, 28 (48%) presented resistance to at least one of the eight antibiotics tested.
Resumo:
The main purpose of this study was to investigate natural infection by Leishmania in phlebotomine females in a visceral-leishmaniasis focus in Antonio João county in Mato Grosso do Sul State, Brazil. Between June and October 2003, the digestive tracts of 81 females captured in Aldeia Campestre, Aldeia Marangatu and Povoado Campestre were dissected. The females were separated by species, location, area and date of capture into 13 groups and kept in ethanol 70%. To identify the Leishmania species using the PCR technique, amplifications of the ribosomal-DNA (rDNA) and mini-exon genes were analyzed. Of the 81 specimens, 77 (95%) were Lutzomyia longipalpis, making this the most common species; only one specimen of each of the species Brumptomyia avellari, Evandromyia cortelezzii, Evandromyia lenti and Nyssomyia whitmani was found. Trypanosomatids were identified in eight of the nine groups of Lutzomyia longipalpis (10.39%) one group from Aldeia Campestre, one from Aldeia Marangatu and six from Povoado Campestre; of the eight groups, one from Aldeia Marangatu and another, with promastigotes forms also confirmed by dissection (1.23%) from Povoado Campestre, were identified by PCR as Leishmania chagasi (2.6%). The other groups gave negative results. These findings indicate that there is a high risk of leishmaniasis transmission in this area.
Resumo:
The use of solid wastes and natural fibres to the production of innovative composites is now a matter of environmental need. A set of hybrid composites constituted of waste rubber particles and sugarcane bagasse fibres into a thermoset composite material are drilled to determine the effect of rubber particle addition and size, sugarcane fibre addition and length and fibre chemical treatment on damage extension and related mechanical properties. Damage extension is determined by enhanced radiography for further damage measurement – diameter and areas – and correlated with mechanical test results — bearing test. The results demonstrated significant effect of the rubber and fibre additions on mechanical properties of the composites.
Resumo:
Dissertação apresentada para cumprimento dos requisitos necessários à obtenção do grau de Doutor em História dos Descobrimentos e da Expansão Portuguesa
Resumo:
A autora aborda o historial, génese e objectivos da Classificação Internacional de Funcionalidade para crianças e jovens, implementada pela Organização Mundial de Saúdeem 2007. Sublinha o papel de complementaridadade da CIF relativamente a outras classificações como a Classificação Internacional de Doenças (CID), em que a primeira visa caracterizar as capacidades e dificuldades de crianças e jovens com deficiência, ou seja, caracterizar do ponto de vista funcional cada criança e jovem, independentemente do diagnóstico etiológico médico. Trata-se da mudança de paradigma bio-médico para a do indivíduo que apresenta determinadas competências e dificuldades, em que estas últimas são definidas em função do ambiente – facilitador ou actuando como barreira. Assim, é dado enfoque ao ambiente para que este seja modificado transformando os factores que actuam como barreira em facilitadores, que anulem ou atenuem as dificuldades. Sendo a deficiência e ou doença uma experiência universal, a CIF vem colmatar uma importante lacuna na dificuldade de comunicação e articulação entre os diversos actores intervenientes no apoio socio educativo e médico destas crianças,criando uma linguagem acessível aos técnicos envolvidos – educadores, terapeutas e outros profissionais ligados à infância, por força envolvidos, dando uma maior ênfase à interacção criança/meio numa perspectiva holística de bem estar bio-psico-social.
Resumo:
In this paper we study several natural and man-made complex phenomena in the perspective of dynamical systems. For each class of phenomena, the system outputs are time-series records obtained in identical conditions. The time-series are viewed as manifestations of the system behavior and are processed for analyzing the system dynamics. First, we use the Fourier transform to process the data and we approximate the amplitude spectra by means of power law functions. We interpret the power law parameters as a phenomenological signature of the system dynamics. Second, we adopt the techniques of non-hierarchical clustering and multidimensional scaling to visualize hidden relationships between the complex phenomena. Third, we propose a vector field based analogy to interpret the patterns unveiled by the PL parameters.
Resumo:
O consumo de energia de forma irracional acarreta desvantagens a nível económico para o consumidor e problemas ambientais para toda a sociedade, como a escassez de recursos naturais e o aumento da poluição. Neste contexto, a otimização energética na indústria, e em particular no setor das borrachas, é indispensável de forma a utilizar racionalmente a energia e assim contribuir para a viabilidade das empresas. Este trabalho, efetuado na Flexocol - Fábrica de Artefactos de Borracha, Lda., teve como principal objetivo efetuar um levantamento energético à unidade fabril e propor alternativas que permitissem a redução do consumo de energia elétrica. Foi ainda realizado um estudo sobre a possibilidade de substituir o n-hexano, solvente utilizado na limpeza dos moldes, por um solvente mais adequado. O levantamento energético efetuado permitiu identificar o consumo das utilidades existentes na Flexocol. Esta empresa consome gasóleo e energia elétrica, sendo esta última, a forma de energia mais consumida correspondendo a 96%. O consumo global de energia é cerca 151 tep anuais, inferior a 500 tep/ano, ou seja é considerada uma empresa não consumidora intensiva de energia. Com base neste levantamento determinou-se os indicadores de consumo específico de energia e da intensidade carbónica, 2,73 tep/ ton e 1684,5 kg CO2/tep. A análise do consumo de energia elétrica dos diferentes equipamentos permitiu verificar que o setor que mais consome energia elétrica é a Vulcanização com 45,8%, seguido do setor da Mistura e Serralharia com 27,5% e 26,7%, respetivamente. O sistema de iluminação nos vários setores foi também alvo de estudo e permitiu identificar a Vulcanização como o setor com mais consumo e o da Mistura como o que menos consome. O estudo das variáveis anteriormente referidas permitiu apresentar algumas propostas de melhoria. Uma das propostas analisada foi implementação de condensadores no quadro parcial de forma a diminuir a energia reativa. Com esta medida prevê-se uma poupança de 5631 €/ano e um retorno de investimento de 0,045 anos. Foi também analisada relativamente à iluminação a possibilidade de instalação de balastros eletrónicos que conduziria a uma poupança na energia elétrica de cerca 7072 kWh/ano, mas com um retorno de investimento desfavorável. Por último estudou-se o solvente alternativo ao n-hexano. A acetona foi o solvente proposto uma vez que tem as propriedades indicadas para o fim a que se destina.