Imageamento interno de testemunhos artificiais através de tomografia ultra-sônica

O Laboratório de Petrofísica da UFRJ dispõe de um tomógrafo ultrasônico para testemunhos, totalmente projetado e construído no próprio Laboratório, sendo este um equipamento inédito no Brasil. O tomógrafo é composto por um conjunto de 32 transdutores piezoelétricos regularmente espaçados em torno do testemunho, gerando 544 valores de tempo de trânsito para cada tomograma adquirido. Este conjunto de tempos de trânsito é invertido, gerando um tomograma que representa a distribuição de velocidades das ondas elásticas dentro do testemunho. Por sua vez, a distribuição de velocidades reproduz o mapeamento de propriedades petrofísicas como composição mineral, saturação fluida e tensões. Com o objetivo de testar a capacidade do tomógrafo para o reconhecimento de heterogeneidades e estruturas internas comumente presentes em testemunhos de sondagem, neste trabalho foram preparados modelos artificiais de testemunhos os quais foram submetidos à tomografia ultra-sônica. Os modelos são constituídos basicamente de cimento-cola com inclusões internas, de diversas formas e tamanhos, compostas de rochas. Os resultados mostram que os tomogramas obtidos identificam a presença dessas heterogeneidades e estruturas, seu tamanho e formas aproximadas, apresentando velocidades indicativas da sua composição. Uma amostra composta apenas por cimento-cola apresentou um tomograma cujas velocidades da onda P estavam restritas a um curto intervalo, indicando uma relativa homogeneidade da amostra. Uma segunda amostra, contendo um cilindro de arenito no seu interior, apresentou um tomograma que representa de forma adequada um corte no plano radial da amostra. Neste tomograma a imagem do cilindro interno de arenito é bastante clara, tanto em tamanho como em forma. Uma terceira amostra contendo um cubo de granito foi também imageada por tomografia ultra-sônica, cujo tomograma apresenta nitidamente a diferença de velocidade da onda P na matriz de cimento em relação à heterogeneidade granítica. O presente estudo identifica ainda as limitações do método quanto à sua resolução, a sua robustez frente a fortes contrastes de velocidades e a possível formação de artefatos na imagem, devido a efeitos como a difração da onda nas bordas agudas das heterogeneidades. Os resultados apresentados neste trabalho sugerem que a tomografia ultra-sônica de testemunhos pode ser aplicada com sucesso na caracterização de depósitos minerais, avaliando a heterogeneidade do depósito e a presença de estruturas e descontinuidades na escala dos testemunhos

Dengue: aspectos epidemiológicos no município de Salgueiro do Sertão Pernambucano, Brasil / Dengue: epidemiological aspects in the municipality of Salgueiro do Sertão Pernambucano, Brazil

A dengue é atualmente a arbovirose mais prevalente no Brasil, configurando-se como um agravo na saúde pública nas últimas décadas. O presente trabalho tem como objetivo analisar estatisticamente dados cadastrados em planilhas eletrônicas do SINAN. Foi realizado um estudo de série histórica observacional do tipo transversal dos casos notificados de dengue no município de Salgueiro- PE, Brasil, entre os anos de 2007 a 2012. O Sinan online notificou para o intervalo de tempo em estudo, 1818 casos de dengue, desses 62,65% eram do sexo feminino e 37,35% do sexo masculino. Os dados demonstram que houve uma quantidade significativa de casos para região, porém a questão da subnotificação é notável, além disso, cabe aos órgãos de saúde pública do município, melhorar a qualidade de prevenção desse agravo

Acidentes ofídicos: perfil epidemiológico na mesorregião do sertão Pernambucano, Brasil / Snaky accidents: epidemiological profile in the meso-region of Pernambuco, Brazil

Os acidentes ofídicos representam sério problema de saúde pública, pela freqüência e morbi-mortalidade, o Brasil tem cerca de 20.000 casos por ano, o coeficiente médio, foi de 13,8 casos/100 mil habitantes. O objetivo do estudo foi analisar os casos notificados de acidentes ofidicos  ocorridos na região do Sertão do Pajeú, Pernambuco, Brasil, entre os anos de 2007 a 2016. ). Os dados foram tabulados em um banco de dados com auxílio do recurso Tabelas e Gráficos do Excel 2010. No período investigado o número de casos de acidentes ofídicos foram  1.375 casos, o município que teve a maior prevalência foi Serra Talhada. Percebe-se que o perfil desse estudo corrobora com perfil do Brasil, onde se tem destaque para sexo masculino

Doença de chagas: tendência epidemiológica por regiões do Brasil / Chagas disease: epidemiological trend by regions of Brazil

A doença de Chagas é uma condição crônica negligenciada com elevada carga de morbimortalidade, no período de 2000 a 2013 foram notificados 1.570 casos de doença de Chagas aguda . Trata-se de um estudo transversal de caráter descritivo, teve como população os casos de notificados doença de chagas aguda dos últimos anos disponíveis do DATASUS,foram dos anos 2013 a 2014 no Brasil. Os dados obtidos foram coletados do DATASUS nas informações de saúde (TABNET). O total de 191 de notificações de doença de chagas aguda no anos de 2014 no Brasil. Os dados epidemiológicos demonstram a necessidade de se aumentar à vigilância na região Norte e incorporar indicadores ambientais para a detecção precoce e prevenção de agravos à saúde da população em relação a doença de chagas

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

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 (>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

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 understanding 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,5,6,7 vast areas of the tropics remain understudied.8,9,10,11 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 underrepresented in biodiversity databases.13,14,15 To worsen this situation, human-induced modifications16,17 may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities 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 organism 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 neglected 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 lost

Geographic patterns of tree dispersal modes in Amazonia and their ecological correlates

Aim: To investigate the geographic patterns and ecological correlates in the geographic distribution of the most common tree dispersal modes in Amazonia (endozoochory, synzoochory, anemochory and hydrochory). We examined if the proportional abundance of these dispersal modes could be explained by the availability of dispersal agents (disperser-availability hypothesis) and/or the availability of resources for constructing zoochorous fruits (resource-availability hypothesis). Time period: Tree-inventory plots established between 1934 and 2019. Major taxa studied: Trees with a diameter at breast height (DBH) ≥ 9.55 cm. Location: Amazonia, here defined as the lowland rain forests of the Amazon River basin and the Guiana Shield. Methods: We assigned dispersal modes to a total of 5433 species and morphospecies within 1877 tree-inventory plots across terra-firme, seasonally flooded, and permanently flooded forests. We investigated geographic patterns in the proportional abundance of dispersal modes. We performed an abundance-weighted mean pairwise distance (MPD) test and fit generalized linear models (GLMs) to explain the geographic distribution of dispersal modes. Results: Anemochory was significantly, positively associated with mean annual wind speed, and hydrochory was significantly higher in flooded forests. Dispersal modes did not consistently show significant associations with the availability of resources for constructing zoochorous fruits. A lower dissimilarity in dispersal modes, resulting from a higher dominance of endozoochory, occurred in terra-firme forests (excluding podzols) compared to flooded forests. Main conclusions: The disperser-availability hypothesis was well supported for abiotic dispersal modes (anemochory and hydrochory). The availability of resources for constructing zoochorous fruits seems an unlikely explanation for the distribution of dispersal modes in Amazonia. The association between frugivores and the proportional abundance of zoochory requires further research, as tree recruitment not only depends on dispersal vectors but also on conditions that favour or limit seedling recruitment across forest types