55 research outputs found
Bryophyte and pteridophyte spores and other palynomorphs in quaternary marine sediments from Campos Basin, southeastern Brazil: Core BU-91-GL-05
Percepção dos alunos de uma universidade pública sobre o Programa de Educação pelo Trabalho para a Saúde
Hormone replacement therapy and the risk of breast cancer: assessment of therapy acceptance in a cohort of previously treated breast cancer patients
Mineralização do carbono e do nitrogênio no solo após sucessivas aplicações de lodo de esgoto
Evaluation of genotoxic and cytotoxic effects of hydroalcoholic extract of Euphorbia tirucalli (Euphorbiaceae) in cell cultures of human leukocytes
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
Uso de AAS em pacientes cardiopatas e ocorrência de Úlcera Perfurada quais as melhores soluções? uma revisão sistemática com metánalise
A administração do ácido acetilsalicílico (AAS) é uma das medidas indicadaspelos médicos em caso de suspeita de infarto agudo do miocárdio. De acordo com os especialistas, o medicamento serve para diminuir a agregação de plaquetas e inibir a formação de coágulos no interior das artérias. O objetivo deste estudo é verificar na literatura o uso do Ácido Acetilsalicílico (AAS) em pessoas cardiopatas e sua possível relação com o aparecimento de úlcera. Trata-se de uma revisão sistemática com base em publicações, dos último cinco anos, que essa temática, extraídas de bases de dados eletrônicas como Scielo, PubMed, Lilacs, BVS, Embase e Medline, em língua inglesa e portuguesa. Dos estudo que se aproximaram do objetivo da pesquisa, muitos não relataram a estreita relação entre o uso AAS e o surgimento de úlcera. Assim, espera-se que este estudo sirva de incentivo para que mais estudos sejam realizados sobre essa temática afim de estabelecer e conhecer se há alguma relação entre o fármaco e a doença
Consistent patterns of common species across tropical tree communities
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
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