46 research outputs found

    New record and distribution extension of Melanemerella brasiliana (Ulmer, 1920) (Ephemeroptera: Melanemerellidae) from Bahia, Brazil

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    Melanemerella brasiliana (Ulmer, 1920) occurs in São Paulo, Rio de Janeiro, and Espírito Santo states, Brazil. Here, we record it for the first time from the state of Bahia. The new record is based on nymphs collected from Serra Bonita Reserve, municipality of Camacan, Bahia

    The Italian National Project of Astrobiology-Life in Space-Origin, Presence, Persistence of Life in Space, from Molecules to Extremophiles

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    The \u2018\u2018Life in Space\u2019\u2019 project was funded in the wake of the Italian Space Agency\u2019s proposal for the development of a network of institutions and laboratories conceived to implement Italian participation in space astrobiology experiments

    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

    The global abundance of tree palms

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    Aim Palms are an iconic, diverse and often abundant component of tropical ecosystems that provide many ecosystem services. Being monocots, tree palms are evolutionarily, morphologically and physiologically distinct from other trees, and these differences have important consequences for ecosystem services (e.g., carbon sequestration and storage) and in terms of responses to climate change. We quantified global patterns of tree palm relative abundance to help improve understanding of tropical forests and reduce uncertainty about these ecosystems under climate change. Location Tropical and subtropical moist forests. Time period Current. Major taxa studied Palms (Arecaceae). Methods We assembled a pantropical dataset of 2,548 forest plots (covering 1,191 ha) and quantified tree palm (i.e., ≥10 cm diameter at breast height) abundance relative to co‐occurring non‐palm trees. We compared the relative abundance of tree palms across biogeographical realms and tested for associations with palaeoclimate stability, current climate, edaphic conditions and metrics of forest structure. Results On average, the relative abundance of tree palms was more than five times larger between Neotropical locations and other biogeographical realms. Tree palms were absent in most locations outside the Neotropics but present in >80% of Neotropical locations. The relative abundance of tree palms was more strongly associated with local conditions (e.g., higher mean annual precipitation, lower soil fertility, shallower water table and lower plot mean wood density) than metrics of long‐term climate stability. Life‐form diversity also influenced the patterns; palm assemblages outside the Neotropics comprise many non‐tree (e.g., climbing) palms. Finally, we show that tree palms can influence estimates of above‐ground biomass, but the magnitude and direction of the effect require additional work. Conclusions Tree palms are not only quintessentially tropical, but they are also overwhelmingly Neotropical. Future work to understand the contributions of tree palms to biomass estimates and carbon cycling will be particularly crucial in Neotropical forests

    Finishing the euchromatic sequence of the human genome

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    The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead

    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

    EVALITA Evaluation of NLP and Speech Tools for Italian - December 17th, 2020

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    Welcome to EVALITA 2020! EVALITA is the evaluation campaign of Natural Language Processing and Speech Tools for Italian. EVALITA is an initiative of the Italian Association for Computational Linguistics (AILC, http://www.ai-lc.it) and it is endorsed by the Italian Association for Artificial Intelligence (AIxIA, http://www.aixia.it) and the Italian Association for Speech Sciences (AISV, http://www.aisv.it)

    Comparative study of distribution of Ephemeroptera (Insecta) nymphs in distinct mesohabitats and stomach contents in Leptophlebiidae

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    Gêneros das diferentes famílias de Ephemeroptera apresentam grande variação na ocorrência entre habitats e dentro destes. Sendo assim, o objetivo do presente trabalho é fazer a comparação da distribuição dos gêneros de efemerópteros em diferentes mesohabitats e, na família Leptophlebiidae, relacionar tal distribuição com exploração de itens alimentares. As coletas foram realizadas na Estação Biológica de Boracéia ? MZUSP. Leptophlebiidae foi a família de maior abundância (54%), seguida pelos Baetidae (44%). Em Leptophlebiidae, Farrodes carioca, Massartella brieni e Miroculis sp. foram os mais comuns, particularmente no mesohabitat remanso. Em Baetidae, o gênero Americabaetis foi o mais numeroso, principalmente no mesohabitat de rápido. As análises de conteúdo estomacal nas ninfas de Leptophlebiidae revelaram, em todos os gêneros, que o item alimentar vegetal superior alóctone foi o mais abundante, seguido de partículas minerais.Genera in the various Ephemeroptera families show much variation in their occurrences among and within habitats. The aim of the present work is to compare the distribution of mayfly genera in different mesohabitats and, in the Leptophlebiidae, relate their distribution with the exploitation of food resources. Samplings were made in the Boracéia Biological Station (23°39\'S, 45°53\'W). The family Leptophlebiidae was the most abundant (54%) followed by the Baetidae (44%). Within the Leptophlebiidae, Farrodes carioca, Massartella brieni and Miroculis sp. were the most common, especially in pools. Americabaetis was the most numerous baetid, particularly in rapids. The analyses of the gut contents showed, for all genera, that the food item \'allochthonous higher plants\' was the most common, followed by mineral particles
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