52 research outputs found

    Arthropod Distribution In A Tropical Rainforest: Tackling A Four Dimensional Puzzle

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    Quantifying the spatio-temporal distribution of arthropods in tropical rainforests represents a first step towards scrutinizing the global distribution of biodiversity on Earth. To date most studies have focused on narrow taxonomic groups or lack a design that allows partitioning of the components of diversity. Here, we consider an exceptionally large dataset (113,952 individuals representing 5,858 species), obtained from the San Lorenzo forest in Panama, where the phylogenetic breadth of arthropod taxa was surveyed using 14 protocols targeting the soil, litter, understory, lower and upper canopy habitats, replicated across seasons in 2003 and 2004. This dataset is used to explore the relative influence of horizontal, vertical and seasonal drivers of arthropod distribution in this forest. We considered arthropod abundance, observed and estimated species richness, additive decomposition of species richness, multiplicative partitioning of species diversity, variation in species composition, species turnover and guild structure as components of diversity. At the scale of our study (2km of distance, 40m in height and 400 days), the effects related to the vertical and seasonal dimensions were most important. Most adult arthropods were collected from the soil/litter or the upper canopy and species richness was highest in the canopy. We compared the distribution of arthropods and trees within our study system. Effects related to the seasonal dimension were stronger for arthropods than for trees. We conclude that: (1) models of beta diversity developed for tropical trees are unlikely to be applicable to tropical arthropods; (2) it is imperative that estimates of global biodiversity derived from mass collecting of arthropods in tropical rainforests embrace the strong vertical and seasonal partitioning observed here; and (3) given the high species turnover observed between seasons, global climate change may have severe consequences for rainforest arthropods.1012SolVin-Solvay SASTRIUnited Nations Environment ProgrammeSmithsonian Institution (Walcott Fund)European Science FoundationGlobal Canopy ProgrammeCzech Science foundation GACR grant [14-36098G]European Social FundCzech Ministry of Education [CZ.1.07/2.3.00/20.0064]U.S. National Science Fundation [DEB-0841885]Australian Research Council [FT100100040]Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)"Investissement d'Avenir'' grant [ANR-10-LABX-25-01]Norwegian Research CouncilGrant Agency of the Czech Republic [14-36098G

    Arthropod distribution in a tropical rainforest: tackling a four dimensional puzzle

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    Quantifying the spatio-temporal distribution of arthropods in tropical rainforests represents a first step towards scrutinizing the global distribution of biodiversity on Earth. To date moststudies have focused on narrow taxonomic groups or lack a design that allows partitioning of the components of diversity. Here, we consider an exceptionally large dataset (113,952 individuals representing 5,858 species), obtained from the San Lorenzo forest in Panama, where the phylogenetic breadth of arthropod taxa was surveyed using 14 protocols targeting the soil, litter, understory, lower and upper canopy habitats, replicated across seasons in 2003 and 2004. This dataset is used to explore the relative influence of horizontal, vertical and seasonal drivers of arthropod distribution in this forest. We considered arthropod abundance, observed and estimated species richness, additive decomposition of species richness, multiplicative partitioning of species diversity, variation in species composition, species turnover and guild structure as components of diversity. At the scale of our study (2km of distance, 40m in height and 400 days), the effects related to the vertical and seasonal dimensions were most important. Most adult arthropods were collected from the soil/ litter or the upper canopy and species richness was highest in the canopy. We compared the distribution of arthropods and trees within our study system. Effects related to the seasonal dimension were stronger for arthropods than for trees. We conclude that: (1) models of beta diversity developed for tropical trees are unlikely to be applicable to tropical arthropods; (2) it is imperative that estimates of global biodiversity derived from mass collecting of arthropods in tropical rainforests embrace the strong vertical and seasonal partitioning observed here; and (3) given the high species turnover observed between seasons, global climate change may have severe consequences for rainforest arthropods

    Arthropod distribution in a tropical rainforest: tackling a four dimensional puzzle

    Get PDF
    Quantifying the spatio-temporal distribution of arthropods in tropical rainforests represents a first step towards scrutinizing the global distribution of biodiversity on Earth. To date most studies have focused on narrow taxonomic groups or lack a design that allows partitioning of the components of diversity. Here, we consider an exceptionally large dataset (113,952 individuals representing 5,858 species), obtained from the San Lorenzo forest in Panama, where the phylogenetic breadth of arthropod taxa was surveyed using 14 protocols targeting the soil, litter, understory, lower and upper canopy habitats, replicated across seasons in 2003 and 2004. This dataset is used to explore the relative influence of horizontal, vertical and seasonal drivers of arthropod distribution in this forest. We considered arthropod abundance, observed and estimated species richness, additive decomposition of species richness, multiplicative partitioning of species diversity, variation in species composition, species turnover and guild structure as components of diversity. At the scale of our study (2km of distance, 40m in height and 400 days), the effects related to the vertical and seasonal dimensions were most important. Most adult arthropods were collected from the soil/litter or the upper canopy and species richness was highest in the canopy. We compared the distribution of arthropods and trees within our study system. Effects related to the seasonal dimension were stronger for arthropods than for trees. We conclude that: (1) models of beta diversity developed for tropical trees are unlikely to be applicable to tropical arthropods; (2) it is imperative that estimates of global biodiversity derived from mass collecting of arthropods in tropical rainforests embrace the strong vertical and seasonal partitioning observed here; and (3) given the high species turnover observed between seasons, global climate change may have severe consequences for rainforest arthropods1012CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQSolVin-Solvay SA; Smithsonian Institution; Smithsonian Tropical Research Institute; United Nations Environment Programme; Smithsonian Institution; Smithsonian National Museum of Natural History; European Science Foundation (ESF); Global Canopy Programme; Czech Science foundation GACR grant; European Social Fund (ESF); Ministry of Education, Youth & Sports - Czech Republic; French National Research Agency (ANR); Research Council of Norway; Grant Agency of the Czech Republi

    Corticosteroid-Induced Immunosuppression ultimately does not compromise the efficacy of antibiotherapy in murine mycobacterium ulcerans Infection

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    Buruli ulcer (BU) is a necrotizing disease of the skin, subcutaneous tissue and bone caused by Mycobacterium ulcerans. It has been suggested that the immune response developed during the recommended rifampicin/streptomycin (RS) antibiotherapy is protective, contributing to bacterial clearance. On the other hand, paradoxical reactions have been described during or after antibiotherapy, characterized by pathological inflammatory responses. This exacerbated inflammation could be circumvented by immunosuppressive drugs. Therefore, it is important to clarify if the immune system contributes to bacterial clearance during RS antibiotherapy and if immunosuppression hampers the efficacy of the antibiotic regimen. METHODOLOGY/PRINCIPAL FINDINGS: We used the M. ulcerans infection footpad mouse model. Corticosteroid-induced immunosuppression was achieved before experimental infection and maintained during combined RS antibiotherapy by the administration of dexamethasone (DEX). Time-lapsed analyses of macroscopic lesions, bacterial burdens, histology and immunohistochemistry were performed in M. ulcerans-infected footpads. We show here that corticosteroid-immunosuppressed mice are more susceptible to M. ulcerans, with higher bacterial burdens and earlier ulceration. Despite this, macroscopic lesions remised during combined antibiotic/DEX treatment and no viable bacteria were detected in the footpads after RS administration. This was observed despite a delayed kinetics in bacterial clearance, associated with a local reduction of T cell and neutrophil numbers, when compared with immunocompetent RS-treated mice. In addition, no relapse was observed following an additional 3 month period of DEX administration. CONCLUSIONS/SIGNIFICANCE: These findings reveal a major role of the RS bactericidal activity for the resolution of M. ulcerans experimental infections even during immunosuppression, and support clinical investigation on the potential use of corticosteroids or other immunosuppressive/anti-inflammatory drugs for the management of BU patients undergoing paradoxical reactions.This work was supported by a grant from the Health Services of Fundação Calouste Gulbenkian, and the Portuguese Science and Technology Foundation (FCT) fellowships SFRH/BD/41598/2007, SFRH/BPD/64032/2009, SFRH/BPD/68547/2010 and SFRH/BD/33573/2009 to TGM, GT, AGF, and JBG, respectively. MS is a Ciência 2007 fello

    Identidad territorial : globalización y patrimonio

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    El presente libro analiza la relación entre los tres con¬ceptos que dan cuerpo a su nombre, con el fin parti¬cular de examinar los impactos que la globalización ha traído sobre el patrimonio construido. Con ello busca explorar los posibles caminos que, para la re¬flexión académica, la investigación aplicada o la polí¬tica pública, pudieran derivarse de las reflexiones que al respecto concentra aquí la mirada de numerosos investigadores provenientes de distintos países. Sobre el particular, el trabajo ofrece un marco con¬ceptual desde donde se ha abordado el fenóme¬no, y a partir del cual se analizan temas como el pensamiento en red; los conflictos socio espaciales que genera el turismo; la relación entre identidad y memoria histórica, así como entre patrimonio y de¬rechos humanos; las tensiones y dilemas que sobre la identidad y el patrimonio trae la globalización y, finalmente, el tema del, denominado en el trabajo, “pensar situado”, como condición a la hora de estu¬diar y entender lo que frente al tema ocurre en cada contexto. Enfoque desde el cual se analizan casos en España, Portugal, Italia, Colombia, Perú, Ecuador, Brasil, Uruguay, Argentina, México, Croacia y, entre otros, Turquía, país, este último, donde los investiga¬dores en pleno efectuaron un trabajo de campo que, junto con las exploraciones en otros contextos, per¬mitió contrastar la teoría con la práctica y extrapolar desde aquí sus conclusiones.Resumen-Abstract. CAPÍTULO 1. Identidad territorial: Elementos transversales y temas críticos, a manera de preámbulo y marco científico. CAPÍTULO 2. Identidad territorial y globalización: Pensar en red. Un reto y un compromiso. CAPÍTULO 3. Morir de éxito. Conflictos socioespaciales del turismo globalizado en ciudades patrimoniales. CAPÍTULO 4. El patrimonio industrial y su compleja puesta en valor: Identidades y memorias en disputa. CAPÍTULO 5. Patrimônio e direitos humanos: A ação do icomos no caso de Bento Rodrigues. CAPÍTULO 6. Tensiones y dilemas de la identidad y el patrimonio en tiempos de globalización CAPÍTULO 7. Identidad territorial, globalización y patrimonio en el valle del Colca, Arequipa, Perú. CAPÍTULO 8. O dilema da patrimonialização em tempos de globalização: Cidade de Paraty, Rio de Janeiro, Brasil. CAPÍTULO 9. Territorialización del paisaje cultural mexicano. Imaginarios y realidades ante la globalización. CAPÍTULO 10. Temas críticos en la relación entre identidad territorial, globalización y patrimonio. CAPÍTULO 11. Pensar situado, identidad territorial y patrimonio. CAPÍTULO 12. Tensiones y desafíos para las relaciones entre lo local y lo global1a

    Global Retinoblastoma Presentation and Analysis by National Income Level.

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    Importance: Early diagnosis of retinoblastoma, the most common intraocular cancer, can save both a child's life and vision. However, anecdotal evidence suggests that many children across the world are diagnosed late. To our knowledge, the clinical presentation of retinoblastoma has never been assessed on a global scale. Objectives: To report the retinoblastoma stage at diagnosis in patients across the world during a single year, to investigate associations between clinical variables and national income level, and to investigate risk factors for advanced disease at diagnosis. Design, Setting, and Participants: A total of 278 retinoblastoma treatment centers were recruited from June 2017 through December 2018 to participate in a cross-sectional analysis of treatment-naive patients with retinoblastoma who were diagnosed in 2017. Main Outcomes and Measures: Age at presentation, proportion of familial history of retinoblastoma, and tumor stage and metastasis. Results: The cohort included 4351 new patients from 153 countries; the median age at diagnosis was 30.5 (interquartile range, 18.3-45.9) months, and 1976 patients (45.4%) were female. Most patients (n = 3685 [84.7%]) were from low- and middle-income countries (LMICs). Globally, the most common indication for referral was leukocoria (n = 2638 [62.8%]), followed by strabismus (n = 429 [10.2%]) and proptosis (n = 309 [7.4%]). Patients from high-income countries (HICs) were diagnosed at a median age of 14.1 months, with 656 of 666 (98.5%) patients having intraocular retinoblastoma and 2 (0.3%) having metastasis. Patients from low-income countries were diagnosed at a median age of 30.5 months, with 256 of 521 (49.1%) having extraocular retinoblastoma and 94 of 498 (18.9%) having metastasis. Lower national income level was associated with older presentation age, higher proportion of locally advanced disease and distant metastasis, and smaller proportion of familial history of retinoblastoma. Advanced disease at diagnosis was more common in LMICs even after adjusting for age (odds ratio for low-income countries vs upper-middle-income countries and HICs, 17.92 [95% CI, 12.94-24.80], and for lower-middle-income countries vs upper-middle-income countries and HICs, 5.74 [95% CI, 4.30-7.68]). Conclusions and Relevance: This study is estimated to have included more than half of all new retinoblastoma cases worldwide in 2017. Children from LMICs, where the main global retinoblastoma burden lies, presented at an older age with more advanced disease and demonstrated a smaller proportion of familial history of retinoblastoma, likely because many do not reach a childbearing age. Given that retinoblastoma is curable, these data are concerning and mandate intervention at national and international levels. Further studies are needed to investigate factors, other than age at presentation, that may be associated with advanced disease in LMICs

    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

    Lutzomyia longipalpis urbanisation and control

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