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This case-control study aimed to assess the risk factors for death from influenza A(H1N1)pdm09 in patients with laboratory confirmation, who had severe acute respiratory illness-SARI and were hospitalized between June 28th and August 29th 2009, in the metropolitan regions of São Paulo and Campinas, Brazil. Medical charts of all the 193 patients who died (cases) and the 386 randomly selected patients who recovered (controls) were investigated in 177 hospitals. Household interviews were conducted with those who had survived and the closest relative of those who had died. 73.6% of cases and 38.1% of controls were at risk of developing influenza-related complications. The 18-to-59-year age group (OR = 2.31, 95%CI: 1.31–4.10 (reference up to 18 years of age)), presence of risk conditions for severity of influenza (OR = 1.99, 95%CI: 1.11–3.57, if one or OR = 6.05, 95%CI: 2.76–13.28, if more than one), obesity (OR = 2.73, 95%CI: 1.28–5.83), immunosuppression (OR = 3.43, 95%CI: 1.28–9.19), and search for previous care associated with the hospitalization (OR = 3.35, 95%CI: 1.75–6.40) were risk factors for death. Antiviral treatment performed within 72 hours of the onset of symptoms (OR = 0.17, 95%CI: 0.08–0.37, if within 48hours, and OR = 0.30, 95%CI: 0.11–0.81, if between 48 and 72 hours) was protective against death. The identification of high-risk patients and early treatment are important factors for reducing morbi-mortality from influenza.  相似文献   
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The applicability of mitochondrial nad6 sequences to studies of DNA and population variability in Lepidoptera was tested in four species of economically important moths and one of wild butterflies. The genetic information so obtained was compared to that of cox1 sequences for two species of Lepidoptera. nad6 primers appropriately amplified all the tested DNA targets, the generated data proving to be as informative and suitable in recovering population structures as that of cox1. The proposal is that, to obtain more robust results, this mitochondrial region can be complementarily used with other molecular sequences in studies of low level phylogeny and population genetics in Lepidoptera.  相似文献   
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Intra- and inter-population genetic variability and the demographic history of Heliothis virescens (F.) populations were evaluated by using mtDNA markers (coxI, coxII and nad6) with samples from the major cotton- and soybean-producing regions in Brazil in the growing seasons 2007/08, 2008/09 and 2009/10. AMOVA indicated low and non-significant genetic structure, regardless of geographical scale, growing season or crop, with most of genetic variation occurring within populations. Clustering analyzes also indicated low genetic differentiation. The haplotype network obtained with combined datasets resulted in 35 haplotypes, with 28 exclusive occurrences, four of them sampled only from soybean fields. The minimum spanning network showed star-shaped structures typical of populations that underwent a recent demographic expansion. The recent expansion was supported by other demographic analyzes, such as the Bayesian skyline plot, the unimodal distribution of paired differences among mitochondrial sequences, and negative and significant values of neutrality tests for the Tajima's D and Fu's F(S) parameters. In addition, high values of haplotype diversity (?) and low values of nucleotide diversity (π), combined with a high number of low frequency haplotypes and values of θ(π)<θ(W), suggested a recent demographic expansion of H. virescens populations in Brazil. This demographic event could be responsible for the low genetic structure currently found; however, haplotypes present uniquely at the same geographic regions and from one specific host plant suggest an initial differentiation among H. virescens populations within Brazil.  相似文献   
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Differences in aggressiveness when competing for environmental resources are the main factor leading to social hierarchy in group living fish. Social status acquired is related to changes in physiological parameters, as metabolic rate. Habitat variation can interfere with aggressive behaviour and promote changes in physiological parameters associated with social status. The primary goal of our study was to investigate how differences in habitat complexity affect the relationship between resting metabolic rate (RMR) and social status in the Amazonian dwarf cichlid Apistogramma agassizii. We compared agonistic interactions between pairs of males in aquaria with different habitat enrichment levels, manipulated by adding shelters. RMR was measured before and after hierarchy establishment. Habitat enrichment promotes changes in aggressive behaviour and influences differences in metabolic rate between dominant and subordinate fish. We observed an increase in biting by dominant fish at high enrichment habitat, which could be related to the increase in territory value. We observed an increase in metabolic rate in dominant fish after hierarchy establishment. However, it occurs only in enriched habitats. We concluded that habitat structure interfere with behavioural characteristics in social hierarchies, as aggressiveness, and changes in aggressive interactions affect metabolic rate in different social ranks in the dwarf cichlid Apistogramma agassizii.  相似文献   
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We compared the bat species composition of three localities in the Brazilian Amazon: continuous forest and fragments at Alter do Chão, Santarém, an area not previously sampled, and continuous forest in two relatively well studied areas, Manaus and Belém. The number of species captured at each locality varied between 17 and 42. Most species occurred at high abundance in continuous forest in the three localities, but only a subset was common in the fragments at Santarém. The relative abundance of bat species in Santarém is different from other localities sampled in the Amazon Basin and the presence of forest fragments may be the most important factor contributing to this difference. Multidi-mensional scaling ordination of sites based on relative abundance indicated distinct assemblages of bat species in the forest fragments in Santarém, and little differentiation of continuous-forest sites from sites in other localities. Continuous forests at Santarém and near Belém were more similar to each other than to continuous forest near Manaus, indicating the possibility of an east-west gradient in bat communities in the Amazon.  相似文献   
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The black lion tamarin (Leontopithecus chrysopygus) is a threatened species due to past destruction of its natural habitat, thus knowledge of its home range size and use is essential in planning for its conservation. I studied one group for 4 months in the Morro do Diabo State Park, in São Paulo State, Brazil. I estimated the home range of the group to be 64 and 127 ha via the quadrat and convex polygon methods, respectively, while a composite method yielded an estimate of 106 ha. They ate insects most frequently (38% of scans), a resource which was distributed throughout their home range. Fruit was the second major resource, but when it was not available, they ate more gum. The exploitation of fruits was associated with dryland forest, while gum-feeding occurred mainly in swamp forest. The study group used a transition zone between dryland and swamp forest most frequently, and all of their sleeping trees were located there. Although the vegetation reached 15–20 m, the group spent most of the time (55%) in the upper understory, between 4 and 8 m high. The study group revealed more specific habitat needs than thought previously, suggesting that the current population may be smaller than estimated.  相似文献   
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Aim The aim of this study was to use compositional changes in tree species along the Amazon River floodplain in Brazil to identify and characterize biogeographic regions that would serve as broad surrogates for conservation planning. Location The main course of the Amazon River in Brazil, covering a river distance of approximately 2800 km. Methods Two sampling methods were employed at specific sites: standardized transects and/or individual‐based samples. Seventy‐three samples were collected from 26 sites at approximately 100‐km intervals along the floodplain. Biogeographic regions were identified by non‐metric multidimensional scaling (NMDS) ordination and by a hierarchical cluster analysis. The relative influence of environmental components (flood depths, annual rainfall, and length of the dry season) on tree species composition and one spatial component (longitude) were analysed by multiple regressions against a one‐dimensional NMDS ordination axis. Results Based on tree species composition, three main biogeographic regions were identified: a western region between Tabatinga and the Negro River confluence; a central region from the Negro River confluence to the Xingu confluence; and an estuarine region from the Xingu confluence to Santana. The regions identified were consistent using different data sets and analytical techniques. Mixed environmental and spatial effects explained most of the variation, but the spatial effect alone had a greater influence on species composition than environmental effects alone. Main conclusions The regions delimited in the analyses differed from those based on geomorphology or World Wildlife Fund (WWF) ecoregions. These results reinforce the need for surrogates to be tested against biological data before they are used to shape approaches to conservation planning. Although a protected area coverage of 25% gives the impression of extensive conservation management on the floodplain, less than 1% of the Amazon’s floodplain in Brazil is strictly protected. The significant compositional differences between regions and the strong spatial variation along the Amazon indicate that strict protection areas should be distributed much more evenly within and between regions.  相似文献   
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Naturally regenerating forests or secondary forests (SFs) are a promising strategy for restoring large expanses of tropical forests at low cost and with high environmental benefits. This expectation is supported by the high resilience of tropical forests after natural disturbances, yet this resilience can be severely reduced by human impacts. Assessing the characteristics of SFs and their ecological integrity (EI) is essential to evaluating their role for conservation, restoration, and provisioning of ecosystem services. In this study, we aim to propose a concept and indicators that allow the assessment and classification of the EI of SFs. To this end, we review the literature to assess how EI has been addressed in different ecosystems and which indicators of EI are most commonly used for tropical forests. Building upon this knowledge we propose a modification of the concept of EI to embrace SFs and suggest indicators of EI that can be applied to different successional stages or stand ages. Additionally, we relate these indicators to ecosystem service provision in order to support the practical application of the theory. EI is generally defined as the ability of ecosystems to support and maintain composition, structure and function similar to the reference conditions of an undisturbed ecosystem. This definition does not consider the temporal dynamics of recovering ecosystems, such as SFs. Therefore, we suggest incorporation of an optimal successional trajectory as a reference in addition to the old-growth forest reference. The optimal successional trajectory represents the maximum EI that can be attained at each successional stage in a given region and enables the evaluation of EI at any given age class. We further suggest a list of indicators, the main ones being: compositional indicators (species diversity/richness and indicator species); structural indicators (basal area, heterogeneity of basal area and canopy cover); function indicators (tree growth and mortality); and landscape proxies (landscape heterogeneity, landscape connectivity). Finally, we discuss how this approach can assist in defining the value of SF patches to provide ecosystem services, restore forests and contribute to ecosystem conservation.  相似文献   
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