686 research outputs found

    The relative importance of forest cover and patch-level drivers for phyllostomid bat communities in the Amazonian Savannas

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    Context: Analyze the multiple dimensions of biodiversity under a local and landscape lens in natural habitats, such as Amazonian savannas, is fundamental for the conservation of species and ecosystems. Objectives: We aim to explore how landscape forest cover and patch-level variables affect the patterns of species abundance, functional traits, and taxonomic, functional and phylogenetic α-diversity of Phyllostomid bats in forest patches of the Savannas of Amapå, in both the wet and dry seasons. Methods: We used mist nets to survey bats in 26 forest patches. We also quantified forest cover in buffers of 500, 1000, 1500, 2000 and 2500 m around each patch, and tree height, basal area, canopy cover, and vegetation clutter in the understorey at the patch level. We used hierarchical partitioning to relate the different indices with our predictor variables. Results: Taxonomic, functional and phylogenetic diversity in the wet season increased with the proportion of forest cover in the 2500 m buffer. Vegetation clutter was negatively related to taxonomic and functional diversity in the wet season. In the dry season, average tree height positively affected taxonomic and functional diversity. Patch-level variables were more important than forest cover in explaining the average functional traits in both seasons. Conclusion: We found seasonal variation in the relationships between components of bat diversity and different drivers. Since both forest cover in the landscape and patch-level variables are important for Phyllostomid bat diversity, conservation plans should consider forest conservation at the landscape level and maintenance of forest patch qualityOpen Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature. Part of the data used in this study was supported by Neotropical Grassland Conservancy (01098803-5), National Geographic Society (EC59186R-19 and NGS-83254R-20), Bat Conservation International (2434131) and Ruford Foundation (25585-1

    ANÁLISE DO COMPORTAMENTO DO CONCRETO REFORÇADO COM FIBRA DE CARBONO POR MEIO DO ENSAIO DE COMPRESSÃO

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    Introdução: As estruturas de concreto armado podem apresentar a necessidade de serem reforçadas, em razĂŁo de algumas falhas de projetos ou atĂ© mesmo o uso inadequado durante sua vida Ăștil. Atualmente, existem vĂĄrios tipos de materiais que podem ser utilizados para o reforço estrutural. O uso dos materiais compĂłsitos, como o tecido de fibra de carbono, surge como uma tecnologia que possui caracterĂ­sticas inovadoras, destacando-se em aplicaçÔes como o reforço das estruturas de concreto armado jĂĄ existentes. Objetivo: Elaborar uma anĂĄlise experimental em corpos de prova cilĂ­ndricos de concreto com a aplicação do tecido de fibra de carbono, objetivando verificar as alteraçÔes em relação a resistĂȘncia Ă  compressĂŁo axial, para comprovar se o tecido de fibra de carbono Ă© uma opção viĂĄvel para o reforço estrutural. Material e MĂ©todos: O foco do estudo pautou-se na experimentação em laboratĂłrio visando verificar a influĂȘncia que a manta de fibra de carbono apresenta no concreto como material de reforço estrutural. Para a realização do ensaio, foram moldados corpos de prova cilĂ­ndricos nas dimensĂ”es de 10 cm de diĂąmetro e 20 cm de altura, obedecendo o especificado da Associação Brasileira de Normas TĂ©cnicas – ABNT, NBR 5738:2015 – Corrigida 2016. Ao todo foram moldados 8 corpos de prova onde, apĂłs o processo de cura de 28 dias, 4 receberam o reforço por meio do tecido de fibra de carbono e 4 foram mantidos em suas condiçÔes originais, para posterior comparação. Passando-se 24 horas apĂłs a aplicação do tecido, espera-se que os elementos jĂĄ apresentem resistĂȘncias maiores, porĂ©m, foi atendido o prazo de cura de 7 dias especificado pelo fabricante do tecido. ApĂłs os 7 dias do processo de cura, efetuou-se o ensaio de compressĂŁo axial em laboratĂłrio credenciado, seguindo o disposto na ABNT NBR 5739:2018. A idade dos corpos de prova ensaiados foi de 36 dias, sendo rompidos aproximadamente 20 horas apĂłs a sua retirada da solução de hidrĂłxido de cĂĄlcio, conforme Tabela 2 – TolerĂąncia de tempo para o ensaio de compressĂŁo em função da idade de ruptura, apresentada na NBR 5739:2018. O equipamento utilizado para o ensaio apresentava o sistema digital de medição de força, mantendo a taxa de tensĂŁo no intervalo de 0.45MPa/s. No ensaio dos corpos de prova sem o tecido, atingiu-se as resistĂȘncias de 36.20MPa, 38.20MPa, 35.00MPa e 41.50MPa. Os corpos de prova reforçados apresentaram 52.39Mpa, 55.80 Mpa, 62.00MPa e 65.90Mpa, respectivamente, sendo os dois Ășltimos reforçados com duas camadas do tecido e os dois primeiros com apenas uma camada. ConsideraçÔes: Pelo mĂ©todo de anĂĄlise comparativa, comprovou-se o significativo ganho de resistĂȘncia dos corpos de prova ensaiados, apresentando um aumento mĂ©dio de 58,42% da mesma. As pesquisas realizadas ao longo do trabalho demonstraram a eficiĂȘncia do reforço, considerando que todos os corpos de provas reforçados, apresentaram aumento de sua resistĂȘncia. Diante disso, os materiais compĂłsitos se apresentam no mercado brasileiro como alternativa tecnolĂłgica eficiente para o reforço de estruturas de concreto

    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

    Pervasive gaps in Amazonian ecological research

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    Large expert-curated database for benchmarking document similarity detection in biomedical literature search

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    Document recommendation systems for locating relevant literature have mostly relied on methods developed a decade ago. This is largely due to the lack of a large offline gold-standard benchmark of relevant documents that cover a variety of research fields such that newly developed literature search techniques can be compared, improved and translated into practice. To overcome this bottleneck, we have established the RElevant LIterature SearcH consortium consisting of more than 1500 scientists from 84 countries, who have collectively annotated the relevance of over 180 000 PubMed-listed articles with regard to their respective seed (input) article/s. The majority of annotations were contributed by highly experienced, original authors of the seed articles. The collected data cover 76% of all unique PubMed Medical Subject Headings descriptors. No systematic biases were observed across different experience levels, research fields or time spent on annotations. More importantly, annotations of the same document pairs contributed by different scientists were highly concordant. We further show that the three representative baseline methods used to generate recommended articles for evaluation (Okapi Best Matching 25, Term Frequency-Inverse Document Frequency and PubMed Related Articles) had similar overall performances. Additionally, we found that these methods each tend to produce distinct collections of recommended articles, suggesting that a hybrid method may be required to completely capture all relevant articles. The established database server located at https://relishdb.ict.griffith.edu.au is freely available for the downloading of annotation data and the blind testing of new methods. We expect that this benchmark will be useful for stimulating the development of new powerful techniques for title and title/abstract-based search engines for relevant articles in biomedical research.Peer reviewe

    Educomunicação e suas åreas de intervenção: Novos paradigmas para o diålogo intercultural

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    oai:omp.abpeducom.org.br:publicationFormat/1O material aqui divulgado representa, em essĂȘncia, a contribuição do VII Encontro Brasileiro de Educomunicação ao V Global MIL Week, da UNESCO, ocorrido na ECA/USP, entre 3 e 5 de novembro de 2016. Estamos diante de um conjunto de 104 papers executivos, com uma mĂ©dia de entre 7 e 10 pĂĄginas, cada um. Com este rico e abundante material, chegamos ao sĂ©timo e-book publicado pela ABPEducom, em seus seis primeiros anos de existĂȘncia. A especificidade desta obra Ă© a de trazer as “Áreas de Intervenção” do campo da Educomunicação, colocando-as a serviço de uma meta essencial ao agir educomunicativo: o diĂĄlogo intercultural, trabalhado na linha do tema geral do evento internacional: Media and Information Literacy: New Paradigms for Intercultural Dialogue

    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 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

    Pervasive gaps in Amazonian ecological research

    Get PDF
    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

    COVID-19 symptoms at hospital admission vary with age and sex: results from the ISARIC prospective multinational observational study

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    Background: The ISARIC prospective multinational observational study is the largest cohort of hospitalized patients with COVID-19. We present relationships of age, sex, and nationality to presenting symptoms. Methods: International, prospective observational study of 60 109 hospitalized symptomatic patients with laboratory-confirmed COVID-19 recruited from 43 countries between 30 January and 3 August 2020. Logistic regression was performed to evaluate relationships of age and sex to published COVID-19 case definitions and the most commonly reported symptoms. Results: ‘Typical’ symptoms of fever (69%), cough (68%) and shortness of breath (66%) were the most commonly reported. 92% of patients experienced at least one of these. Prevalence of typical symptoms was greatest in 30- to 60-year-olds (respectively 80, 79, 69%; at least one 95%). They were reported less frequently in children (≀ 18 years: 69, 48, 23; 85%), older adults (≄ 70 years: 61, 62, 65; 90%), and women (66, 66, 64; 90%; vs. men 71, 70, 67; 93%, each P < 0.001). The most common atypical presentations under 60 years of age were nausea and vomiting and abdominal pain, and over 60 years was confusion. Regression models showed significant differences in symptoms with sex, age and country. Interpretation: This international collaboration has allowed us to report reliable symptom data from the largest cohort of patients admitted to hospital with COVID-19. Adults over 60 and children admitted to hospital with COVID-19 are less likely to present with typical symptoms. Nausea and vomiting are common atypical presentations under 30 years. Confusion is a frequent atypical presentation of COVID-19 in adults over 60 years. Women are less likely to experience typical symptoms than men
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