61 research outputs found

    Lesão Pulmonar Associada Ao Uso De Cigarros Eletrônicos: Revisão De Literatura

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    E-cigarettes, a widely used emerging product, are facing growing popularity despite little research into their health risks. Electronic Cigarette Use Associated Lung Injury, or EVALI, has become a prominent concern in recent research, expanding the need to understand the health effects of vaping, given the diversity of technologies and liquids involved. An integrative review was carried out to analyze the relationship between electronic cigarettes and lung injuries, using the PubMed database. 664 articles were selected, with inclusion criteria based on human studies published between 2018 and 2023. The analysis, exclusion and selection process was carefully conducted by the authors. Electronic cigarettes, consisting of a battery, atomizer and liquid, stand out due to the uncertainty about their health effects, in contrast to traditional cigarettes. EVALI, predominantly associated with the vaporization of THC products, reveals serious symptoms and significant risks. The complex composition of e-liquids, especially when exposed to high temperatures, generates harmful substances, including carbonyl compounds, suspected of causing oxidative stress and inflammation in the airways. The integrative review highlights the lack of consensus on the safety of electronic cigarettes and the urgency in understanding the associated risks. EVALI, as a diagnosis of exclusion, highlights the need for immediate investigation in the event of respiratory symptoms. Treatment and monitoring of EVALI patients requires a careful approach, considering clinical and risk factors. Public education about potential dangers and cessation strategies becomes crucial, especially among young people.Los cigarrillos electrónicos, un producto emergente ampliamente utilizado, se enfrentan a una creciente popularidad a pesar de la poca investigación sobre sus riesgos para la salud. La lesión pulmonar asociada al uso de cigarrillos electrónicos, o EVALI, se ha convertido en una preocupación destacada en investigaciones recientes, ampliando la necesidad de comprender los efectos del vapeo en la salud, dada la diversidad de tecnologías y líquidos involucrados. Se realizó una revisión integradora para analizar la relación entre los cigarrillos electrónicos y las lesiones pulmonares, utilizando la base de datos PubMed. Se seleccionaron 664 artículos, con criterios de inclusión basados ​​en estudios en humanos publicados entre 2018 y 2023. El proceso de análisis, exclusión y selección fue cuidadosamente realizado por los autores. Los cigarrillos electrónicos, compuestos por batería, atomizador y líquido, destacan por la incertidumbre sobre sus efectos sobre la salud, a diferencia de los cigarrillos tradicionales. EVALI, predominantemente asociado con la vaporización de productos de THC, revela síntomas graves y riesgos importantes. La compleja composición de los e-líquidos, especialmente cuando se exponen a altas temperaturas, genera sustancias nocivas, incluidos compuestos carbonílicos, sospechosos de causar estrés oxidativo e inflamación en las vías respiratorias. La revisión integradora destaca la falta de consenso sobre la seguridad de los cigarrillos electrónicos y la urgencia de comprender los riesgos asociados. EVALI, como diagnóstico de exclusión, destaca la necesidad de investigación inmediata en caso de síntomas respiratorios. El tratamiento y seguimiento de los pacientes con EVALI requiere un enfoque cuidadoso, considerando los factores clínicos y de riesgo. La educación pública sobre los peligros potenciales y las estrategias para dejar de fumar se vuelve crucial, especialmente entre los jóvenes.Os cigarros eletrônicos, produto emergente amplamente utilizado, enfrentam crescente popularidade apesar da escassa investigação sobre seus riscos à saúde. A Lesão Pulmonar Associada ao Uso de Cigarro Eletrônico, ou EVALI, tornou-se uma preocupação destacada nas pesquisas recentes, ampliando a necessidade de compreender os efeitos da vaporização na saúde, dada a diversidade de tecnologias e líquidos envolvidos. Realizou-se uma revisão integrativa para analisar a relação entre cigarros eletrônicos e lesões pulmonares, utilizando a base de dados PubMed. Foram selecionados 664 artigos, com critérios de inclusão baseados em estudos humanos publicados entre 2018 e 2023. O processo de análise, exclusão e seleção foi conduzido de forma criteriosa pelos autores. Os cigarros eletrônicos, compostos por bateria, atomizador e líquido, destacam-se pela incerteza sobre seus efeitos à saúde, em contraste com os tradicionais. A EVALI, predominantemente associada à vaporização de produtos com THC, revela sintomas graves e riscos significativos. A composição complexa dos e-líquidos, especialmente quando expostos a altas temperaturas, gera substâncias nocivas, incluindo compostos carbonílicos, suspeitos de causar estresse oxidativo e inflamação nas vias aéreas. A revisão integrativa destaca a falta de consenso sobre a segurança dos cigarros eletrônicos e a urgência em compreender os riscos associados. A EVALI, como diagnóstico de exclusão, destaca a necessidade de investigação imediata diante de sintomas respiratórios. O tratamento e o acompanhamento de pacientes EVALI requerem abordagem cuidadosa, considerando fatores clínicos e de risco. A educação pública sobre os perigos potenciais e estratégias de cessação torna-se crucial, especialmente entre os jovens

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

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    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

    Geography and ecology shape the phylogenetic composition of Amazonian tree communities

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    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

    Geography and ecology shape the phylogenetic composition of Amazonian tree communities

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    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 (R2^{2} = 19% overall for combined spatial/environmental effects). The phylogenetic composition also shows substantial spatial patterns not related to the environmental variables we quantified (R2^{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

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

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    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

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    Pervasive gaps in Amazonian ecological research

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    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

    Consistent patterns of common species across tropical tree communities

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    Trees structure the Earth’s most biodiverse ecosystem, tropical forests. The vast number of tree species presents a formidable challenge to understanding these forests, including their response to environmental change, as very little is known about most tropical tree species. A focus on the common species may circumvent this challenge. Here we investigate abundance patterns of common tree species using inventory data on 1,003,805 trees with trunk diameters of at least 10 cm across 1,568 locations1,2,3,4,5,6 in closed-canopy, structurally intact old-growth tropical forests in Africa, Amazonia and Southeast Asia. We estimate that 2.2%, 2.2% and 2.3% of species comprise 50% of the tropical trees in these regions, respectively. Extrapolating across all closed-canopy tropical forests, we estimate that just 1,053 species comprise half of Earth’s 800 billion tropical trees with trunk diameters of at least 10 cm. Despite differing biogeographic, climatic and anthropogenic histories7, we find notably consistent patterns of common species and species abundance distributions across the continents. This suggests that fundamental mechanisms of tree community assembly may apply to all tropical forests. Resampling analyses show that the most common species are likely to belong to a manageable list of known species, enabling targeted efforts to understand their ecology. Although they do not detract from the importance of rare species, our results open new opportunities to understand the world’s most diverse forests, including modelling their response to environmental change, by focusing on the common species that constitute the majority of their trees.Publisher PDFPeer reviewe

    Unraveling Amazon tree community assembly using Maximum Information Entropy: a quantitative analysis of tropical forest ecology

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    In a time of rapid global change, the question of what determines patterns in species abundance distribution remains a priority for understanding the complex dynamics of ecosystems. The constrained maximization of information entropy provides a framework for the understanding of such complex systems dynamics by a quantitative analysis of important constraints via predictions using least biased probability distributions. We apply it to over two thousand hectares of Amazonian tree inventories across seven forest types and thirteen functional traits, representing major global axes of plant strategies. Results show that constraints formed by regional relative abundances of genera explain eight times more of local relative abundances than constraints based on directional selection for specific functional traits, although the latter does show clear signals of environmental dependency. These results provide a quantitative insight by inference from large-scale data using cross-disciplinary methods, furthering our understanding of ecological dynamics

    Rarity of monodominance in hyperdiverse Amazonian forests.

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    Tropical forests are known for their high diversity. Yet, forest patches do occur in the tropics where a single tree species is dominant. Such "monodominant" forests are known from all of the main tropical regions. For Amazonia, we sampled the occurrence of monodominance in a massive, basin-wide database of forest-inventory plots from the Amazon Tree Diversity Network (ATDN). Utilizing a simple defining metric of at least half of the trees ≥ 10 cm diameter belonging to one species, we found only a few occurrences of monodominance in Amazonia, and the phenomenon was not significantly linked to previously hypothesized life history traits such wood density, seed mass, ectomycorrhizal associations, or Rhizobium nodulation. In our analysis, coppicing (the formation of sprouts at the base of the tree or on roots) was the only trait significantly linked to monodominance. While at specific locales coppicing or ectomycorrhizal associations may confer a considerable advantage to a tree species and lead to its monodominance, very few species have these traits. Mining of the ATDN dataset suggests that monodominance is quite rare in Amazonia, and may be linked primarily to edaphic factors
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