1000 resultados para DIOGO DO COUTO
Resumo:
Fine litter dynamics within the canopy differ from litter dynamics on the forest floor for reasons such as differences in microclimate, substrate, disturbance level, stratum influence and decomposition rates. This study is the first attempt to quantify the fine litter accumulated in the canopy of Central Amazonian forests. We compared the canopy litter accumulation to fine litter-layer on forest floor and to other forests and also investigated which were the mostly accumulated litter omponents. We found that Central Amazonian Rainforest intercepts greater fine litter in the canopy (294 g.m-2) compared to other forest formations with higher winds speed as in a Costa Rican Cloud Forest (170 g.m-2). The mean canopy fine litter accumulated at the end of the dry season was less than a half of that on soil surface (833 g.m-2) and the fine wood component dominates the canopy samplings (174 g.m-2) while leafy component predominate on soil surface litter (353 g.m-2).
Resumo:
The effects of dietary short chain fructooligosaccharides (scFOS) incorporation on hematology, fish immune status, gut microbiota composition, digestive enzymes activities, and gut morphology, was evaluated in gilthead sea bream (Sparus aurata) juveniles reared at 18 °C and 25 °C. For that purpose, fish with 32 g were fed diets including 0, 0.1, 0.25 and 0.5% scFOS during 8 weeks. Overall, scFOS had only minor effects on gilthead sea bream immune status. Lymphocytes decreased in fish fed the 0.1% scFOS diet. Fish fed the 0.5% scFOS diet presented increased nitric oxide (NO) production, while total immunoglobulins (Ig) dropped in those fish, but only in the ones reared at 25 °C. Red blood cells, hemoglobin, bactericidal activity and NO were higher at 25 °C, whereas total white blood cells, circulating thrombocytes, monocytes and neutrophils were higher at 18 °C. In fish fed scFOS, lymphocytes were higher at 18 °C. Total Ig were also higher at 18 °C but only in fish fed 0.1% and 0.5% scFOS diets. No differences in gut bacterial profiles were detected by PCR-DGGE (polymerase chain reaction denaturing gradient gel electrophoresis) between dietary treatments. However, group's similarity was higher at 25 °C. Digestive enzymes activities were higher at 25 °C but were unaffected by prebiotics incorporation. Gut morphology was also unaffected by dietary prebiotic incorporation. Overall, gut microbiota composition, digestive enzymes activities and immunity parameters were affected by rearing temperature whereas dietary scFOS incorporation had only minor effects on these parameters. In conclusion, at the tested levels scFOS does not seem worthy of including it in gilthead sea bream juveniles diets.
Resumo:
Os solos hidromórficos, comuns na Amazônia e no Pantanal, estão sujeitos à alternância natural de períodos de alagamento e secamento, que conduzem a uma formação e características diferenciadas. Estes solos guardam estreita relação com a natureza do material de origem e com os processos de deposição e sedimentação. O objetivo neste trabalho foi avaliar as características químicas, morfológicas e mineralógicas de três perfis de solos do Pantanal Norte Matogrossense (Planossolo, Plintossolo e Gleissolo), a fim de interpretar as relações entre suas propriedades e o ambiente em que foram formados. Os Planossolos e Gleissolos possuem maior fertilidade natural, evidenciada pelos valores expressivos de CTC (capacidade de troca de cátions) e saturação por bases. Os menores teores de Fe2O3 do Planossolo estão relacionados com a redução e remoção do Fe durante sua gênese A mineralogia da fração areia dos solos é constituída principalmente de quartzo, nódulos e concreções de Fe e de Mn, e em menor grau, biotita, muscovita e traços de turmalina, magnetita, ilmenita, epídoto, zircão e rutilo. Os solos apresentaram perfil mineralógico semelhante na fração argila, constituído por caulinita, esmectita, ilita e interestratificados do tipo ilita-esmectita. A mineralogia da fração argila dos solos foi compatível com as diferenças químicas constatadas entre eles, pois o Planossolo apresentou argila de maior atividade relativa às esmectitas e interestratificados ilita/esmectita, com maior soma de bases trocáveis e CTC, enquanto o Plintossolo e o Gleissolo, cujo mineral predominante foi a caulinita, apresentaram baixo teor de bases trocáveis e menor CTC.
Resumo:
BACKGROUND: The zoonosis bovine tuberculosis (TB) is known to be responsible for a considerable proportion of extrapulmonary TB. In Mozambique, bovine TB is a recognised problem in cattle, but little has been done to evaluate how Mycobacterium bovis has contributed to human TB. We here explore the public health risk for bovine TB in Maputo, by characterizing the isolates from tuberculous lymphadenitis (TBLN) cases, a common manifestation of bovine TB in humans, in the Pathology Service of Maputo Central Hospital, in Mozambique, during one year. RESULTS: Among 110 patients suspected of having TBLN, 49 had a positive culture result. Of those, 48 (98 %) were positive for Mycobacterium tuberculosis complex and one for nontuberculous mycobacteria. Of the 45 isolates analysed by spoligotyping and Mycobacterial Interspersed Repetitive Unit - Variable Number Tandem Repeat (MIRU-VNTR), all were M. tuberculosis. No M. bovis was found. Cervical TBLN, corresponding to 39 (86.7 %) cases, was the main cause of TBLN and 66.7 % of those where from HIV positive patients. We found that TBLN in Maputo was caused by a variety of M. tuberculosis strains. The most prevalent lineage was the EAI (n?=?19; 43.2 %). Particular common spoligotypes were SIT 48 (EAI1_SOM sublineage), SIT 42 (LAM 9), SIT 1 (Beijing) and SIT53 (T1), similar to findings among pulmonary cases. CONCLUSIONS: M. tuberculosis was the main etiological agent of TBLN in Maputo. M. tuberculosis genotypes were similar to the ones causing pulmonary TB, suggesting that in Maputo, cases of TBLN arise from the same source as pulmonary TB, rather than from an external zoonotic source. Further research is needed on other forms of extrapulmonary TB and in rural areas where there is high prevalence of bovine TB in cattle, to evaluate the risk of transmission of M. bovis from cattle to humans.
Resumo:
Relatório de estágio de mestrado em Negócios Internacionais
Resumo:
Dissertação de mestrado integrado em Arquitectura
Resumo:
Dissertação de mestrado integrado em Arquitetura (área de especialização em Cultura Arquitetónica)
Resumo:
Coupled carbon/climate models are predicting changes in Amazon carbon and water cycles for the near future, with conversion of forest into savanna-like vegetation. However, empirical data to support these models are still scarce for Amazon. Facing this scenario, we investigated whether conservation status and changes in rainfall regime have influenced the forest-savanna mosaic over 20 years, from 1986 to 2006, in a transitional area in Northern Amazonia. By applying a spectral linear mixture model to a Landsat-5-TM time series, we identified protected savanna enclaves within a strictly protected nature reserve (Maracá Ecological Station - MES) and non-protected forest islands at its outskirts and compared their areas among 1986/1994/2006. The protected savanna enclaves decreased 26% in the 20-years period at an average rate of 0.131 ha year-1, with a greater reduction rate observed during times of higher precipitation, whereas the non-protected forest islands remained stable throughout the period of study, balancing the encroachment of forests into the savanna during humid periods and savannization during reduced rainfall periods. Thus, keeping favorable climate conditions, the MES conservation status would continue to favor the forest encroachment upon savanna, while the non-protected outskirt areas would remain resilient to disturbance regimes. However, if the increases in the frequency of dry periods predicted by climate models for this region are confirmed, future changes in extension and directions of forest limits will be affected, disrupting ecological services as carbon storage and the maintenance of local biodiversity.
Resumo:
Os besouros rola-bostas são insetos copro-necrófagos e utilizam primariamente fezes e carcaça de mamíferos como fonte de alimento e nidificação. Estes insetos são sensíveis à modificação do habitat principalmente relacionados à cobertura da vegetação. A substituição da floresta Amazônica por pastagem altera drasticamente o habitat das espécies nativas e acarreta redução da riqueza de espécies e modificação na composição das assembleias locais. O objetivo deste trabalho foi compreender os efeitos da substituição da floresta nativa por pastagem introduzida na riqueza, abundância, composição de espécies e estrutura das guildas alimentares dos besouros rola-bostas no sudoeste da Amazônia brasileira. Foram coletados 10.073 indivíduos de besouros rola-bostas pertencentes a 84 espécies e 22 gêneros. As florestas (seis fragmentos de floresta secundária) apresentaram 71 espécies em sua maioria com abundância intermediária. As pastagens (áreas vizinhas onde a floresta original foi substituída por pastagens introduzidas) apresentaram redução significativa no número de espécies, e composição de espécies diferente. Nas florestas a maioria das espécies foi considerada generalista, enquanto as pastagens apresentaram maior abundância de espécies coprófagas o que demonstra uma modificação na guilda alimentar causado pela substituição da floresta por pastagem. Entre as 30 espécies coletadas nas pastagens, doze estão presentes em vegetação aberta nativa (cerrado e chaco). Isto retrata, provavelmente, um processo de colonização regional recente. Onde espécies de besouros rola-bostas, oriundas de áreas abertas, estão invadindo as pastagens amazônicas.
Resumo:
Noble metal powders containing gold and silver have been used for many centuries, providing different colours in the windows of the medieval cathedrals and in ancient Roman glasses. Nowadays, the interest in nanocomposite materials containing noble nanoparticles embedded in dielectric matrices is related with their potential use for a wide range of advanced technological applications. They have been proposed for environmental and biological sensing, tailoring colour of functional coatings, or for surface enhanced Raman spectroscopy. Most of these applications rely on the so-called localised surface plasmon resonance absorption, which is governed by the type of the noble metal nanoparticles, their distribution, size and shape and as well as of the dielectric characteristics of the host matrix. The aim of this work is to study the influence of the composition and thermal annealing on the morphological and structural changes of thin films composed of Ag metal clusters embedded in a dielectric TiO2 matrix. Since changes in size, shape and distribution of the clusters are fundamental parameters for tailoring the properties of plasmonic materials, a set of films with different Ag concentrations was prepared. The optical properties and the thermal behaviour of the films were correlated with the structural and morphological changes promoted by annealing. The films were deposited by DC magnetron sputtering and in order to promote the clustering of the Ag nanoparticles the as-deposited samples were subjected to an in-air annealing protocol. It was demonstrated that the clustering of metallic Ag affects the optical response spectrum and the thermal behaviour of the films.
Resumo:
The ternary aluminium oxynitride (AlNxOy) system offers the possibility to obtain a wide range of properties by tailoring the ratio between pure Al, AlNx and AlOy and therefore opening a significant number of possible applications. In this work the thermal behaviour of AlNxOy thin films was analysed by modulated infrared radiometry (MIRR), taking as reference the binary AlOy and AlNx systems. MIRR is a non-contact and non-destructive thermal wave measurement technique based on the excitation, propagation and detection of temperature oscillations of very small amplitudes. The intended change of the partial pressure of the reactive gas (N2 and/or O2) influenced the target condition and hence the deposition characteristics which, altogether, affected the composition and microstructure of the films. Based on the MIRR measurements and their qualitative and quantitative interpretation, some correlations between the thermal transport properties of the films and their chemical/physical properties have been found. Furthermore, the potential of such technique applied in this oxynitride system, which present a wide range of different physical responses, is also discussed. The experimental results obtained are consistent with those reported in previous works and show a high potential to fulfil the demands needed for the possible applications of the systems studied. They are clearly indicative of an adequate thermal response if this particular thin film system is aimed to be applied in small sensor devices or in electrodes for biosignal acquisition, such as those for electroencephalography or electromyography as it is the case of the main research area that is being developed in the group.
Resumo:
In this work, the thermal stability of TiAgx thin films, deposited by magnetron sputtering, was evaluated, envisaging their application in biomedical devices, namely as electrodes for biosignal acquisition. Based on the composition and microstructural characterization, a set of four representative TiAgx thin films was selected in order to infer whether they are thermally stable in terms of functional properties. In order to achieve this purpose, the structural and morphological evolution of the films with annealing temperature was correlated with their electrical, mechanical and thermal properties. Two distinct zones were identified and two samples from each zone were extensively analysed. In the first zone (zone I), Ti was the main component (Ti-rich zone) while in the second, zone II, the Ag content was more significant. The selected samples were annealed in vacuum at four different temperatures up to 500 oC. For the samples produced within zone I, small microstructural changes were observed due to the recrystallization of the Ti structure and grain size increment. Also, no significant changes were observed with annealing temperature regarding the f l ’ functional properties, being thermally stable up to 500 oC. For higher Ag contents (zone II) the energy supplied by thermal treatments was sufficient to activate the crystallization of Ti-Ag intermetallic phases. A strong increase of the grain size of these phases was also reported. The structural and morphological organization proved to be determinant for the physical responses of the TiAgx system. The hardness and Y g’s modulus were significantly improved with the formation of the intermetallic phases. The silver addition and annealing treatments also played an important role in the electrical conductivity of the films, which was once again improved by the formation of Ti-Ag phases. The thermal diffusivity of the films was practically unchanged with the heat-treatment. This set of results shows that this intermetallic-like thin film system has good thermal stability up to high temperatures (as high as 500 oC), which in case of the highest Ag content zone is particularly evident for electrical and mechanical properties, showing an important improvement. Hardness increases about three times, while resistivity values become half of those from the lowest Ag contents zone. These set of characteristics are consistent with the targeted applications, namely in terms of biomedical sensing devices.
Resumo:
OBJETIVOS: Procura-se analisar as atuais evidências empíricas e teóricas sobre o modo de operar nas intervenções comportamentais dialéticas. Procedeu-se igualmente à análise da eficácia dessa terapia no tratamento da bulimia nervosa e no transtorno da compulsão alimentar periódica. MÉTODO: Realizou-se uma revisão agregativa da literatura, recorrendo às palavras-chave "dialectical behavior therapy", "bulimia nervosa" e "binge eating disorder" nas bases de dados PsycInfo e MedLine e em livros da especialidade, sob o critério da atualidade e premência das publicações levantadas. RESULTADOS: A terapia comportamental dialética, inicialmente desenhada para o transtorno de personalidade borderline, tem-se estendido a outros transtornos do eixo I. Sua aplicação às perturbações alimentares sustentase num paradigma dialético com o recurso das estratégias comportamentais e cognitivas. Esse modelo permite aos pacientes uma regulação mais efetiva dos estados afetivos negativos, reduzindo a probabilidade da ocorrência de comportamentos bulímicos e de compulsão alimentar periódica. CONCLUSÃO: Embora escasseiem estudos sobre a sua eficácia, os resultados existentes parecem comprovar a eficácia da terapia comportamental dialética nas populações descritas.
Resumo:
Dissertação de mestrado integrado em Engenharia e Gestão de Sistemas de Informação
Resumo:
OBJETIVO: Investigar a qualidade de vida (QV) de pacientes com o diagnóstico de esquizofrenia que cumprem medida de segurança em regime fechado. MÉTODOS: Estudo epidemiológico com delineamento transversal, realizado com pacientes de um hospital de custódia. As entrevistas foram conduzidas utilizando questionário sociodemográfico e a escala de qualidade de vida Quality of Life Scale (QLS-BR), específica para pacientes com diagnóstico de esquizofrenia. Foi realizada análise descritiva e multivariada. A associação entre os escores de QV e as características clínicas, sociodemográficas e do delito foi obtida por análise multivariada, através da árvore de decisão, por meio do algoritmo Chi-squared Automatic Interaction Detector (CHAID). RESULTADOS: Participaram deste estudo 54 pacientes, sendo 90,7% do sexo masculino, com a média de idade de 40 anos. Todos os domínios de qualidade de vida, inclusive o global, apresentaram escores compatíveis com uma QV muito baixa. O domínio ocupacional apresentou-se como o mais comprometido. Maior duração da doença, ter cometido homicídio e estar com idade superior a 40 anos foram as variáveis associadas a uma baixa qualidade de vida pela análise multivariada. CONCLUSÃO: Evidenciou-se uma baixa QV dos pacientes que cumprem medida de segurança em regime fechado, realidade que precisa ser modificada a partir da viabilização de mudanças nas políticas brasileiras.