Intercalação e ordenação de arquivos por algoritmos de fusão.

Os algoritmos que utilizam técnicas de fusão (merge) de arquivos para a intercalação ou a ordenação de dois ou mais arquivos seqüenciais são conhecidos há muitos anos. Entretanto, as facilidades atualmente disponíveis para manipulação de bases de dados e arquivos como, por exemplo, a ampla e crescente utilização de sistemas gerenciadores de banco de dados, fazem com que esses algoritmos, em geral, rápidos e de fácil desenvolvimento e entendimento, sejam pouco considerados por profissionais e pouco estudados em cursos de graduação. Contudo, essas soluções de intercalação e ordenação são facilmente implementadas em ambientes de computação com poucos recursos e podem ser utilizadas em memória principal ou secundária, de modo interativo ou recursivo, gerando eficientes soluções que, praticamente, não dependem do aporte computacional do sistema hospedeiro

Quality of life in spondyloarthritis : analysis of a large Brazilian cohort

Objetivo: analisar as variáveis demográficas e clínicas associadas à diminuição da qualidade de vida em uma grande coorte brasileira de pacientes com espondiloartrite (EpA). Métodos: Foi aplicado um protocolo de pesquisa único a 1.465 pacientes brasileiros classificados como tendo EpA de acordo com os critérios do European Spondyloarthropaties Study Group (ESSG), atendidos em 29 centros de referência em reumatologia do Brasil. Foram registradas as variáveis clínicas e demográficas. A qualidade de vida foi analisada por meio do questionário Ankylosing Spondylitis Quality of Life (ASQoL). Resultados: A pontuação média do ASQoL foi de 7,74 (+ 5,39). Ao analisar doenças específicas no grupo de EpA, as pontuações do ASQoL não apresentaram diferença estatisticamente significativa. Os dados demográficos mostraram piores escores de ASQoL associados ao gênero feminino (p = 0,014) e etnia negra (p < 0,001). Quanto aos sintomas clínicos, a dor na região glútea (p = 0,032), a dor cervical (p < 0,001) e a dor no quadril (p = 0,001), estiveram estatisticamente associadas a piores escores no ASQoL. O uso contínuo de fármacos anti-inflamatórios não esteroides (p < 0,001) e agentes biológicos (p = 0,044) esteve associado a escores mais elevados de ASQoL, enquanto outros medicamentos não interferiram nos escores do ASQoL. Conclusão: Nesta grande série de pacientes com EpA, o sexo feminino e a etnia negra, bem como sintomas predominantemente axiais, estiveram associados a uma qualidade de vida reduzida.Objective: to analyze quality of life and demographic and clinical variables associated to its impairment in a large Brazilian cohort of patients with spondyloarthritis (SpA). Methods: A common protocol of investigation was applied to 1465 Brazilian patients classified as SpA according to the European Spondyloarthropaties Study Group (ESSG) criteria, attended at 29 reference centers for Rheumatology in Brazil. Clinical and demographic variables were recorded. Quality of life was analyzed through the Ankylosing Spondylitis Quality of Life (ASQoL) questionnaire. Results: The mean ASQoL score was 7.74 (± 5.39). When analyzing the specific diseases in the SpA group, the ASQoL scores did not present statistical significance. Demographic data showed worse scores of ASQoL associated with female gender (p = 0.014) and African-Brazilian ethnicity (p < 0.001). Regarding clinical symptoms, buttock pain (p = 0.032), cervical pain (p < 0.001) and hip pain (p = 0.001), were statistically associated with worse scores of ASQoL. Continuous use of nonsteroidal anti-inflammatory drugs (p < 0.001) and biologic agents (p = 0.044) were associated with higher scores of ASQoL, while the other medications did not interfere with the ASQoL scores. Conclusion: In this large series of patients with SpA, female gender and African-Brazilian ethnicity, as well as predominant axial symptoms, were associated with impaired quality of life

Geography and ecology shape the phylogenetic composition of Amazonian tree communities

Aim: Amazonia hosts more tree species from numerous evolutionary lineages, both young and ancient, than any other biogeographic region. Previous studies have shown that tree lineages colonized multiple edaphic environments and dispersed widely across Amazonia, leading to a hypothesis, which we test, that lineages should not be strongly associated with either geographic regions or edaphic forest types. Location: Amazonia. Taxon: Angiosperms (Magnoliids; Monocots; Eudicots). Methods: Data for the abundance of 5082 tree species in 1989 plots were combined with a mega-phylogeny. We applied evolutionary ordination to assess how phylogenetic composition varies across Amazonia. We used variation partitioning and Moran\u27s eigenvector maps (MEM) to test and quantify the separate and joint contributions of spatial and environmental variables to explain the phylogenetic composition of plots. We tested the indicator value of lineages for geographic regions and edaphic forest types and mapped associations onto the phylogeny. Results: In the terra firme and várzea forest types, the phylogenetic composition varies by geographic region, but the igapó and white-sand forest types retain a unique evolutionary signature regardless of region. Overall, we find that soil chemistry, climate and topography explain 24% of the variation in phylogenetic composition, with 79% of that variation being spatially structured (R$^{2}$ = 19% overall for combined spatial/environmental effects). The phylogenetic composition also shows substantial spatial patterns not related to the environmental variables we quantified (R$^{2}$ = 28%). A greater number of lineages were significant indicators of geographic regions than forest types. Main Conclusion: Numerous tree lineages, including some ancient ones (>66 Ma), show strong associations with geographic regions and edaphic forest types of Amazonia. This shows that specialization in specific edaphic environments has played a long-standing role in the evolutionary assembly of Amazonian forests. Furthermore, many lineages, even those that have dispersed across Amazonia, dominate within a specific region, likely because of phylogenetically conserved niches for environmental conditions that are prevalent within regions

Geography and ecology shape the phylogenetic composition of Amazonian tree communities

AimAmazonia hosts more tree species from numerous evolutionary lineages, both young and ancient, than any other biogeographic region. Previous studies have shown that tree lineages colonized multiple edaphic environments and dispersed widely across Amazonia, leading to a hypothesis, which we test, that lineages should not be strongly associated with either geographic regions or edaphic forest types.LocationAmazonia.TaxonAngiosperms (Magnoliids; Monocots; Eudicots).MethodsData for the abundance of 5082 tree species in 1989 plots were combined with a mega-phylogeny. We applied evolutionary ordination to assess how phylogenetic composition varies across Amazonia. We used variation partitioning and Moran's eigenvector maps (MEM) to test and quantify the separate and joint contributions of spatial and environmental variables to explain the phylogenetic composition of plots. We tested the indicator value of lineages for geographic regions and edaphic forest types and mapped associations onto the phylogeny.ResultsIn the terra firme and várzea forest types, the phylogenetic composition varies by geographic region, but the igapó and white-sand forest types retain a unique evolutionary signature regardless of region. Overall, we find that soil chemistry, climate and topography explain 24% of the variation in phylogenetic composition, with 79% of that variation being spatially structured (R2 = 19% overall for combined spatial/environmental effects). The phylogenetic composition also shows substantial spatial patterns not related to the environmental variables we quantified (R2 = 28%). A greater number of lineages were significant indicators of geographic regions than forest types.Main ConclusionNumerous tree lineages, including some ancient ones (&gt;66 Ma), show strong associations with geographic regions and edaphic forest types of Amazonia. This shows that specialization in specific edaphic environments has played a long-standing role in the evolutionary assembly of Amazonian forests. Furthermore, many lineages, even those that have dispersed across Amazonia, dominate within a specific region, likely because of phylogenetically conserved niches for environmental conditions that are prevalent within regions

Mapping density, diversity and species-richness of the Amazon tree flora

Using 2.046 botanically-inventoried tree plots across the largest tropical forest on Earth, we mapped tree species-diversity and tree species-richness at 0.1-degree resolution, and investigated drivers for diversity and richness. Using only location, stratified by forest type, as predictor, our spatial model, to the best of our knowledge, provides the most accurate map of tree diversity in Amazonia to date, explaining approximately 70% of the tree diversity and species-richness. Large soil-forest combinations determine a significant percentage of the variation in tree species-richness and tree alpha-diversity in Amazonian forest-plots. We suggest that the size and fragmentation of these systems drive their large-scale diversity patterns and hence local diversity. A model not using location but cumulative water deficit, tree density, and temperature seasonality explains 47% of the tree species-richness in the terra-firme forest in Amazonia. Over large areas across Amazonia, residuals of this relationship are small and poorly spatially structured, suggesting that much of the residual variation may be local. The Guyana Shield area has consistently negative residuals, showing that this area has lower tree species-richness than expected by our models. We provide extensive plot meta-data, including tree density, tree alpha-diversity and tree species-richness results and gridded maps at 0.1-degree resolution

Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio