978 resultados para Physico-Climatic
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With an example taken from a late-Hauterivian series of the Lusitanian Basin (Portugal), we will demonstrate the sedimentary record of orbital pattern variations and, consequently, climate variations in an inner platform environment with patterns and isolation changes, allows us to establish 4 major orders of periodicity related to orbital components:- The large cycles ob bed thickness variation, constituted by 31-32 beds, recording the 400 ky eccentricity cycle component;- The medium cycles, represented by byndles of 8-9 beds, related to the 100 ky eccentricity cycle component; - The small cycles, of 3-5 beds, recording the 41 ky obliquity components;- The very small cycles, of 2 beds, related to the 22 ky and 26 ky precession components. The mean duration of each bed is around 11.8 ky, a number very close to that of the precession hemi-cycle. Climatic control on qualitative production is confirmed by the close relation between the bed thickness variations, the insolation variability and the variation of micritized elements concentrations.
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Mestrado em Engenharia Química – Ramo Optimização Energética na Indústria Química
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Em Portugal existem muitos espaços comerciais e industriais em que as necessidades térmicas de arrefecimento são muito superiores às necessidades de aquecimento devido aos ganhos internos que advêm da existência de equipamentos e da iluminação dos edifícios, assim como, da presença das pessoas. A instalação de sistemas convencionais de ar condicionado para espaços comerciais e industriais de grande dimensão está geralmente associada ao transporte de grandes caudais de ar, e consequentemente, a elevados consumos de energia primária, e também, elevados custos de investimento, de manutenção e de operação. O arrefecedor evaporativo é uma solução de climatização com elevada eficiência energética, cujo princípio de funcionamento promove a redução do consumo de energia primária nos edifícios. A metodologia utilizada baseou-se na criação de uma ferramenta informática de simulação do funcionamento de um protótipo de um arrefecedor evaporativo. Foi efetuada a modelação matemática das variáveis dinâmicas envolvidas, dos processos de transferência de calor e de massa, assim como dos balanços de energia que ocorrem no arrefecedor evaporativo. A ferramenta informática desenvolvida permite o dimensionamento do protótipo do arrefecedor evaporativo, sendo determinadas as caraterísticas técnicas (potência térmica, caudal, eficiência energética, consumo energético e consumo e água) de acordo com o tipo de edifício e com as condições climatéricas do ar exterior. Foram selecionados três dimensionamentos de arrefecedores evaporativos, representativos de condições reais de uma gama baixa, média e elevada de caudais de ar. Os resultados obtidos nas simulações mostram que a potência de arrefecimento (5,6 kW, 16,0 kW e 32,8 kW) e o consumo de água (8 l/h, 23,9 l/h e 48,96 l/h) aumentam com o caudal de ar do arrefecedor, 5.000 m3/h, 15.000 m3/h e 30.000 m3/h, respetivamente. A eficácia de permuta destes arrefecedores evaporativos, foi de 69%, 66% e 67%, respetivamente. Verificou-se que a alteração de zona climática de V1 para V2 implicou um aumento de 39% na potência de arrefecimento e de 20% no consumo de água, e que, a alteração de zona climática de V2 para V3 implicou um aumento de 39% na potência de arrefecimento e de 39% no consumo de água. O arrefecedor evaporativo apresenta valores de consumo de energia elétrica entre 40% a 80% inferiores aos dos sistemas de arrefecimento convencionais, sendo este efeito mais intenso quando a zona climática de verão se torna mais severa.
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In order to investigate epidemiological aspects of hepatocellular carcinoma (HCC) in Brazil, basic informations about cases diagnosed from January 1992 to December 1994 were requested to several medical centers of different Brazilian States. A simple questionnaire included age, sex, alcohol abuse (over 80g/day), associated liver cirrhosis, persistent HBV infection (HBsAg), HCV infection (anti-HCV) and serum levels of alpha fetoprotein. 287 cases, over 16 years old, from 19 medical centers of 8 States (Pará, Bahia, Minas Gerais, Espirito Santo, Rio de Janeiro, São Paulo, Paraná and Rio Grande do Sul) were analysed. The results showed: (a) Mean age was 56.3 ± 14.4 for men and 54.7 ± 16.8 yr for women and the male/female ratio was 3.4:1. (b) 69.6% were caucasians, 21.8% mullatoes, 4.8% orientals and 3.7% blacks. (c) HBsAg (+) in 77/236 cases (41.6%) without differences between males and females. (d) Anti-HCV (+) in 52/193 cases (26.9%). (e) 7/180 cases were positive both for HBsAg and anti-HCV (3.8%). (f) There was chronic alcoholism in 88/235 cases (37%). (g) HCC was found in cirrhotic livers in 71.2% of 202 cases in which the presence or absence of cirrhosis was reported. (h) Alpha-fetoprotein above 20 ng/ml was found in 124/172 cases (72%) and above 500 ng/ml only in 40 cases (23.2%). These results showed that the HCC in Brazil has an intermediate epidemiological pattern as compared to those from areas of low and high incidence of the tumor. In spite of the high frequency of the association of HCC with the HBV and/or HCV infections, 42% of 180 cases were negative both for HBsAg and anti-HCV, indicating the possible role of other etiological factors. The comparison of data from different States showed some regional differences: higher frequency of associated HBsAg in Pará, Bahia, Minas Gerais and Espírito Santo, higher frequency of associated HCV infection in Rio de Janeiro, São Paulo and States of the Southern region and low frequency of associated liver cirrhosis in Salvador and Rio de Janeiro (55.5 and 50% respectively). Further investigation will be necessary to study the presence of other possible etiological factors as aflatoxins, suggested by the favourable climatic conditions for food contamination by fungi in the majority Brazilian regions
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The increase of electricity demand in Brazil, the lack of the next major hydroelectric reservoirs implementation, and the growth of environmental concerns lead utilities to seek an improved system planning to meet these energy needs. The great diversity of economic, social, climatic, and cultural conditions in the country have been causing a more difficult planning of the power system. The work presented in this paper concerns the development of an algorithm that aims studying the influence of the issues mentioned in load curves. Focus is given to residential consumers. The consumption device with highest influence in the load curve is also identified. The methodology developed gains increasing importance in the system planning and operation, namely in the smart grids context.
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Dissertação apresentada na Faculdade de Ciências e Tecnologia da Universidade Nova de Lisboa para obtenção do Grau de Mestre em Engenharia Biomédica
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O principal objectivo desta dissertação foi avaliar a evolução hidrogeoquímica das águas minerais de Entre‐os‐Rios, para uma melhor compreensão do modelo hidrogeológico conceptual deste sistema hidromineral. Desta forma, foram coligidos diversos dados hidroquímicos, quer das nascentes clássicas (Torre, Curveira, Ardias, Arcos Esquerda e Arcos Direita), quer do furo Barbeitos. Foram compiladas e analisadas oitenta análises hidroquímicas no período 1938‐2012, incluindo características organolépticas (cheiro, cor e turbidez), diversas propriedades físico-químicas (temperatura, pH, condutividade eléctrica, sulfuração, etc), os principais catiões e aniões (bicarbonato, fluoreto, sódio, lítio, etc) e os elementos vestigiários (chumbo, tungsténio, boro, etc). Além disso, foram integrados os dados históricos disponíveis de finais do século XIX e inícios do século XX. Foram igualmente reunidos e discutidos alguns dados isotópicos (oxigénio‐18, deutério e trítio). O recurso hidromineral de Entre‐os‐Rios está condicionado pela litologia e pelas condições tectónicas. As análises químicas revelaram que as águas minerais de Entre‐os‐Rios apresentam uma estabilidade química nos últimos 100 anos. Estas águas são orto‐ a hipertermais, fracamente mineralizadas, de reacção alcalina, sulfídricas, bicarbonatadas sódicas, carbonatadas e muito fluoretadas. Estas características são claramente distintas das águas normais da região. As águas de Entre‐os‐Rios são muito semelhantes às águas minerais de S. Vicente e, em diversos parâmetros, bastante diferentes das águas minerais das Caldas da Saúde. Os dados isotópicos permitiram concluir que as águas de Entre‐os‐Rios têm uma origem meteórica, com um tempo de residência longo no sistema aquífero, e que são, muito provavelmente, submodernas, com uma recarga anterior a 1952. Na região de Entre‐os‐Rios coexistem três sistemas aquíferos, um sistema granítico superficial, livre e um sistema livre a semi‐confinado, ambos com circulação de águas normais, e um sistema aquífero granítico, profundo, confinado, com circulação de água mineral.
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Between March and July 1996, a focalized epidemic outbreak of cutaneous leishmaniasis in General Vedia, province of Chaco, associated to the gallery forest of the Oro river was verified. The incidence rate in the area, which was 0-2/000 cases in preceding years, reached 8/000 cases in 1996. The risk of symptomatic infection was similar between sexes, but was different when analizing the different age groups by sex, suggesting a greater relative importance of the peridomestic transmission for the females and of the transmission in the subtropical forest for the males. Specimens of Lutzomyia intermedia, a species already incriminated as a vector of Leishmaniasis in other provinces of northern Argentina, were captured and identified in the focus locality in May 1996. The possible causes of the outbreak related to the climatic variables and the vector abundance are analyzed and the results in the framework of possible preventive and control activities are discussed.
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Thesis for the Master degree in Structural and Functional Biochemistry
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In order to decrease the risk of severe wildfire, prescribed fire has recently been adopted in Portugal and elsewhere in the Mediterranean as a major tool for reducing the fuel load instead of manual or mechanical removal of vegetation. There has been some research into its impact on soils in shrublands and grasslands, but to date little research has been conducted in forested areas in the region. As a result, the impact of prescribed fire on the physico-chemical soil characteristics of forest soils has been assumed to be minimal, but this has not been demonstrated. In this study, we present the results of a monitoring campaign of a detailed pre- and post-prescribed fire assessment of soil properties in a long-unburnt P. pinaster plantation, NW Portugal. The soil characteristics examined were pH, total porosity, bulk density, moisture content, organic matter content and litter/ash quantity. The results show that there was no significant impact on the measured soil properties, the only effect being confined to minor changes in the upper 1 cm of soil. We conclude that provided the fire is carried out according to strict guidelines in P. pinaster forest, a minimal impact on soil properties can be expected.
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In view of the high circulation of migratory birds and the environmental and climatic conditions which favor the proliferation of arthropods, the Brazilian Pantanal is susceptible to circulation of arboviruses. However, the amount of data concerning arbovirus vectors in this area is scarce; therefore the aim of this study was to conduct a preliminary investigation of Culicidae species in the Nhecolândia Sub-region of South Pantanal, Brazil and their potential importance in the arbovirus transmission. A total of 3684 specimens of mosquitoes were captured, 1689 of which caught in the rainy season of 2007, were divided into 78 pools and submitted to viral isolation, Semi-Nested RT-PCR and Nested RT-PCR, with a view to identifying the most important arboviruses in Brazil. Simultaneously, 70 specimens of ticks found blood-feeding on horses were also submitted to the same virological assays. No virus was isolated and viral nucleic-acid detection by RT-PCR was also negative. Nevertheless, a total of 22 Culicidae species were identified, ten of which had previously been reported as vectors of important arboviruses. The diversity of species found blood-feeding on human and horse hosts together with the arboviruses circulation previously reported suggest that the Nhecolândia Sub-region of South Pantanal is an important area for arbovirus surveillance in Brazil.
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Dissertation submitted in partial fulfillment of the requirements for the Degree of Master of Science in Geospatial Technologies.
INVENTORY OF MOSQUITOES (DIPTERA: CULICIDAE) IN CONSERVATION UNITS IN BRAZILIAN TROPICAL DRY FORESTS
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In Brazil, most studies of the Culicidae family are concentrated in rainforest regions. As such, there is a lack of knowledge regarding the diversity of Culicidae in regions with different climatic and vegetational characteristics. The aim of this study was to compile an inventory of Culicidae in protected areas of the semi-arid region of the state of Minas Gerais, Brazil, in order to better understand the diversity of the family within this region. The study was conducted across four protected areas in the northern region of the state, in tropical dry forest (TDF) fragments. Sampling methods included Shannon trap and CDC light trap, as well as active collection. A total of 11,219 mosquito specimens were collected between August 2008 and July 2012, belonging to 11 genera and 45 species; 15 new records for the state of Minas Gerais were registered, as well as 26 new records for semi-arid regions within the state. The high number of new Culicidae records in this region demonstrates the importance of inventory studies for increasing the knowledge of culicid biodiversity in Minas Gerais, and in particular within semi-arid regions of the state.
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Dissertation submitted in partial fulfillment of the requirements for the Degree of Master of Science in Geospatial Technologies.
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Dissertation submitted in partial fulfillment of the requirements for the Degree of Master of Science in Geospatial Technologies.