526 resultados para 988


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Owing to their high vulnerability and low adaptive capacity, Caribbean islands have legitimate concerns about their future, based on observational records, experience with current patterns and consequences of climate variability, and climate model projections. Although emitting less than 1% of global greenhouse gases, islands from the region have already perceived a need to reallocate scarce resources away from economic development and poverty reduction, and towards the implementation of strategies to adapt to the growing threats posed by global warming (Nurse and Moore, 2005). The objectives of this Report are to conduct economic analyses of the projected impacts of climate change to 2050, within the context of the IPCC A2 and B2 scenarios, on the coastal and marine resources of the British Virgin Islands (BVI). The Report presents a valuation of coastal and marine services; quantitative and qualitative estimates of climate change impacts on the coastal zone; and recommendations of possible adaptation strategies and costs and benefits of adaptation. A multi-pronged approach is employed in valuing the marine and coastal sector. Direct use and indirect use values are estimated. The amount of economic activity an ecosystem service generates in the local economy underpins estimation of direct use values. Tourism and fisheries are valued using the framework developed by the World Resources Institute. Biodiversity is valued in terms of the ecological functions it provides, such as climate regulation, shoreline protection, water supply erosion control and sediment retention, and biological control, among others. Estimates of future losses to the coastal zone from climate change are determined by considering: (1) the effect of sea level rise on coastal lands; and (2) the effect of a rise in sea surface temperature (SST) on coastal waters. Discount rates of 1%, 2% and 4% are employed to analyse all loss estimates in present value terms. The overall value for the coastal and marine sector is USD $1,606 million (mn). This is almost 2% larger than BVI’s 2008 GDP. Tourism and recreation comprise almost two-thirds of the value of the sector. By 2100, the effects of climate change on coastal lands are projected to be $3,988.6 mn, and $2,832.9 mn under the A2 and B2 scenarios respectively. In present value terms, if A2 occurs, losses range from $108.1-$1,596.8 mn and if B2 occurs, losses range from $74.1-$1,094.1 mn, depending on the discount rate used. Estimated costs of a rise in SST in 2050 indicate that they vary between $1,178.0 and $1,884.8 mn. Assuming a discount rate of 4%, losses range from $226.6 mn for the B2 scenario to $363.0 mn for the A2 scenario. If a discount rate of 1% is assumed, estimated losses are much greater, ranging from $775.6-$1,241.0 mn. Factoring in projected climate change impacts, the net value of the coastal and marine sector suggests that the costs of climate change significantly reduce the value of the sector, particularly under the A2 and B2 climate change scenarios for discount rates of 1% and 2%. In contrast, the sector has a large, positive, though declining trajectory, for all years when a 4% discount rate is employed. Since the BVI emits minimal greenhouse gases, but will be greatly affected by climate change, the report focuses on adaptation as opposed to mitigation strategies. The options shortlisted are: (1) enhancing monitoring of all coastal waters to provide early warning alerts of bleaching and other marine events; (2) introducing artificial reefs or fish-aggregating devices; (3) introducing alternative tourist attractions; (4) providing retraining for displaced tourism workers; and (5) revising policies related to financing national tourism offices to accommodate the new climatic realities. All adaptation options considered are quite justifiable in national terms; each had benefit-cost ratios greater than 1.

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The Goliath grouper (Epinephelus itajara) is one of the most endangered species of fish of the subfamily Epinephelinae. Slow to develop and mature, and dependent on mangrove habitats for breeding, the species also suffers intense harvesting, which has reduced drastically in numbers in many areas. To contribute to the understanding of the characteristics of E. itajara populations, we conducted a molecular genetics study of the species, focusing on populations from the Northern Brazilian coast. The mtDNA control region (D-loop) of 116 individuals from five localities (Bragança, Ajuruteua, Parnaíba, Fortaleza and Natal) was analysed, and a sequence of 499 base pairs identified. Analyses of the sequences indicated that genetic variability was generally lower in E. itajara than in other endangered species of the genus. AMOVA found no significant grouping structure among the populations. Nested Clade Analysis revealed a significant association between genetic variability and geographic distribution among only three populations (Ajuruteua, Parnaíba and Natal). Genetic diversity was higher in populations from the Amazon region, which may be related to the better conservation of mangrove habitats in this area. Therefore, the present study could be used for the implementation of conservation and management measures in order to protect and consolidate these populations.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Na Amazônia o cromo é empregado principalmente na indústria de couro e de madeira, sendo responsável por vários problemas de saúde porque é tóxico para os seres vivos. A remoção de cromo de efluentes industriais é feita por meio de diversos processos como a adsorção. Este trabalho mostra os resultados da adsorção de Cr(VI) por carvão ativado granular comercial (CAG) como adsorvente de soluções diluídas empregando um sistema de adsorção batelada com controle de pH. Os grupos funcionais da superfície do CAG foram determinados pelo método de Boehm. Além disso, o efeito do pH na adsorção de Cr(VI), o equilíbrio e a cinética de adsorção foram estudados nas condições experimentais (pH = 6, MA = 6g, tempo de adsorção 90min.). Na superfície do CAG, os grupos carboxílicos foram determinados em maior concentração (MAS=0,43 mmol/gCAG), estes, presentes em concentrações elevadas aumentam a adsorção do metal, principalmente em valores de pH ácidos. A capacidade de adsorção é dependente do pH da solução, devido a sua influência nas propriedades de superfície do CAG e nas diferentes formas iônicas das soluções de Cr(VI). Os dados de equilíbrio da adsorção foram ajustados satisfatoriamente pela isoterma de Langmuir (R2=0,988), tipo favorável. A partir da cinética de adsorção a 5mg/L e 20mg/L, os resultados obtidos foram compatíveis com o valor limite preconizado na legislação nacional (Res. nº 357/05). Portanto, para o sistema experimental utilizando CAG foi eficiente na remoção de Cr(VI) a partir de correntes líquidas contendo baixas concentrações do metal.

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Samples were collected from 100 carcasses in a slaughterhouse exporter, located within the State of São Paulo, sampled over a year through the sponge method, applied to the chest of the animal. Samples were taken at three points, denominated A, B and C, each carcass sampled at three points located in the following steps: after bleeding (A) after skinning (B) and after washing (C). Research was conducted for Listeria sp., E. coli O157, Salmonella spp. and Micro-organism (Petrifilms ® AC, EC and EB). Listeria or E. coli O157 were not isolated in any of the 300 samples. Salmonella spp. was isolated in nine, eight at point A and one at point B. For Mesophiles, scores ranged from 0 to 6.8 log UFC/cm²; for Total coliforms, 0 to 4.57 log UFC/cm² and E. coli from 0 to 4.38 log UFC/cm². With the results obtained and compared with the literature, it is concluded that the establishment in this study has both sanitary quality (due to the low prevalence of pathogens) and hygienic quality (due to the sharp decrease in the microbial load of indicators along the line.

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Better knowledge of the anthropogenic soils can help create future scenarios for the Amazon region through information that supports the sustainable planning. The aim of this study was to evaluate the spatial variability of soil physical anthropogenic and not anthropogenic in the region of Manipur, AM. In the study area we selected two, one with no anthropogenic soils (native forest) and another with anthropogenic soils (black earth archaeological). In each area, we established a grid measuring 70 x 70 m and the soils were sampled at the points of intersection of the grid with regular spacing of 10 by 10 feet, making a total of 64 sampling points in each landscape. Soil samples were collected at a depth from 0.0 to 0.10 I did the analyzes physical (texture, bulk density, macroporosity, microporososidade, porosity and aggregate stability). Then, the data were subjected to descriptive statistics and geostatistics. It was found that the anthropogenic and non-anthropogenic soils showed different behaviors in relation ace their spatial structures. The spatial variability that prevailed in anthropogenic and non-anthropogenic soil was moderate and weak indicating that these soils are strongly linked to changes in the soil by extrinsic factors. The soil was observed anthropogenic best results for total porosity, microporosity and bulk density, showing superior characteristics compared for agronomic soil not anthropogenic. And the range of values found in the above two areas were used in the mesh, showing greater spatial continuity in these environments.

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This work presents a new and simple electrode, which may be used to achieve the electrochemical response of ground solids or insoluble samples. Ore samples from Morro Velho Mine (Brazil) were employed to exemplify the use of such electrodes. The new electrode avoids the use of binders or other agents overcoming major deterioration problems. (C) 2002 Published by Elsevier Science B.V.

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The sagittal split ramus osteotomy (SSRO) is a surgical technique used widely to treat many congenital and acquired mandibular discrepancies. Stabilization of the osteotomy site and the potential for skeletal relapse after the procedure are still major problems. The aim of this study was to compare the mechanical stability of six methods of rigid fixation in SSRO using a biomechanical test model. Sixty polyurethane replicas of human hemimandibles were divided into six groups. In group I, the osteotomies were fixed with two four-hole titanium miniplates; in group II, with one four-hole miniplate; in group III, with one four-hole miniplate + a bicortical screw; in group IV, with a grid miniplate; in group V, with a four-hole locking miniplate; and in group VI, with a six-hole miniplate. A linear load in the premolar region was applied to the hemimandibles. The resistance forces (N) needed to displace the distal segment by 1, 3, and 5 mm were recorded and the data transmitted from the load cell to a computer. One-way analysis of variance with Tukey's post hoc test was performed to compare the means between groups. For the three displacement conditions, there was a strong tendency for the 2.0-mm plate + screw and the grid plate to have higher values.

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Pós-graduação em Agronomia (Irrigação e Drenagem) - FCA

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)