1,090 research outputs found

    Editorial : Tropical Climate Variability and Change: Impacts in the Amazon

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    Vast amounts of data from satellites and ground-based systems, and improvements on modeling techniques, allows a better understanding of Earth processes and advances on climate science. The tropics play a key role on global climate processes, and the tropical forest is a sensitive biome in the global hydrological and carbon cycles. In particular, the Amazon region includes about one half of the world’s tropical forest, and relatively small change in Amazon forest dynamics have the potential to substantially affect the rate of climate change. This Research Topics focus on recent finding on the impacts of tropical climate variability and change over the Amazon ecosystem using satellite data, ground-based measurements or reanalysis climate data

    La importancia de la histéresis en las exportaciones de manufacturas de los países de la UEM

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    En este trabajo se pretende comprobar la posible existencia de histéresis en la oferta de exportaciones de manufacturas en algunos países de la zona del euro, es decir, se analiza si los movimientos transitorios del tipo de cambio tienen un impacto permanente sobre las exportaciones. La presencia de costes irrecuperables en la entrada y salida del mercado a los que se enfrentan los productores puede justificar la existencia de histéresis en el comercio, ya que las empresas exportadoras tomarían en consideración el tipo de cambio futuro como una variable adicional a la hora de decidir si se entra o no en el mercado, afectando de esta forma al volumen de exportación agregado. Así, el trabajo presenta una estimación de un modelo de oferta y demanda de exportaciones de manufacturas para la mayoría de los países de la zona euro, donde la oferta toma en cuenta la evolución futura del tipo de cambio a partir de la estimación secuencial de sus dos primeros momentos. De acuerdo con los resultados obtenidos, el tipo de cambio esperado no es, en la mayor parte de los casos, una variable explicativa de la evolución de la oferta de exportaciones. De este modo, en contra de la evidencia disponible con datos de empresas, el análisis macroeconómico efectuado no detecta efectos de histéresis significativos en la oferta de exportaciones.Histéresis; tipo de cambio; exportaciones; unión monetaria; zona euro;

    Differential Immune-Reactivity and Subcellular Distribution Reveal the Multifunctional Character of Profilin in Pollen as Major Effect of Sequences Polymorphism

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    Trabajo presentado al Annual Meeting of the American Society of Agronomy and Crop Science Society and Soil Science Society of America, celebrado en Cincinnati (USA) del 21 al 24 de octubre de 2012.Profilin, one of the major allergen (Ole e 2) of olive (Olea europaea L.) pollen, are broadly distributed actin-monomer-binding proteins (ABP). They display a major regulatory role in actin cytoskeleton dynamics, driving cell morphogenesis, sexual reproduction, and translating signals into cellular responses to different environmental stresses. Plants exhibit multiple profilin isoforms w ith distinctive biochemical properties, and differentially regulated. How ever, it is still an open question w hether these profilin isoforms, generated by multiple gene sequence polymorphism, are functionally different, as well as the role of that polymorphism in pollen allergy. Particularly, in differential epitopes generation, profilin isoforms sensitization and cross-reactivity among cultivars, and even among species. In the present study, w e have used mature pollen from olive, birch, hazel, timothy-grass, and maize, in addition to olive germinating pollen and seeds, w ith the aim to analyze the immune-reactivity and subcellular localization of profilin by using polyclonal and specific isoforms antibodies against olive and maize profilins. The results show ed immune-reactivity differences betw een the five species analyzed, betw een olive cultivars, as w ell as between reproductive and vegetative profilins. Furthermore, the existence of different profilin isoforms w as revealed along pollen germination stages. A differential subcellular distribution of profilin isoforms w as found in olive pollen. They w ere localized in the nucleus, pollen aperture regions, pollen and tube w alls and pollen tip, in addition to a general cytoplasmic distribution, in comparison to controls. Data suggest that profilin family might contain numerous functionally distinctive isoforms, spatial-temporal differentially expressed and regulated during vegetative development, pollen maturation and pollen tube grow th. Furthermore, differential immune-reactivity revealed in the study might point out the involvement of common shared and specific epitopes, generated by sequence polymorphism, in differential olive pollen cultivar sensitization of allergenic patients, and cross-reaction to pollen from different species.This study was supported by the following European Regional Development Fund cofinanced grants: MCINN BFU 2004-00601/BFI, BFU 2008-00629, BFU2011-22779, CICE (Junta de Andalucía) P2010-CVI15767, P2010-AGR6274, P2011-CVI-7487, P2011-CVI-7487, and by the coordinated project Spain/Germany MEC HA2004-0094.Peer reviewe

    COVID-19 e o olho: quanto sabemos realmente? Uma revisão das melhores evidências

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    To identify and classify available information regarding COVID-19 and eye care according to the level of evidence, within four main topics of interest: evidence of the virus in tears and the ocular surface, infection via the conjunctival route, ocular manifestations, and best practice recommendations. A structured review was conducted in PubMed, ScienceDirect, LILACS, SciELO, the Cochrane Library and Google Scholar on COVID-19 and ophthalmology. The Oxford Centre for Evidence Based Medicine 2011 Levels of Evidence worksheet was used for quality assessments. 1018 items were identified in the search; 26 records were included in the qualitative synthesis, which encompassed 6 literature reviews, 10 case series or cross-sectional studies, 4 case reports, and 6 intervention descriptions. Seventeen out of 26 records (65%) were categorized as level 5 within the Oxford CBME methodology grading system, the rest were level 4. The evidence generated on COVID-19 and ophthalmology to date is limited, although this is understandable given the circumstances. Both the possible presence of viral particles in tears and conjunctiva, and the potential for conjunctival transmission remain controversial. Ocular manifestations are not frequent and could resemble viral infection of the ocular surface. Most recommendations are based on the strategies implemented by Asian countries during previous coronavirus outbreaks. There is a need for substantive studies evaluating these strategies in the setting of SARS-CoV-2. In the meantime, plans for applying these measures must be implemented with caution, taking into account the context of each individual country, and undergo regular evaluation.Identificar e classificar as informações disponíveis sobre o COVID-19 e o tratamento oftalmológico de acordo com o nível de evidência, dentro de quatro tópicos principais de interesse: evidência do vírus nas lágrimas e na superfície ocular, infecção pela via conjuntival, manifestações oculares e recomendações de melhores práticas. Foi realizada uma revisão estruturada no PubMed, ScienceDirect, LILACS, SciELO, Biblioteca Cochrane e Google Scholar no COVID-19 e oftalmologia. A planilha de Níveis de Evidência 2011 do Oxford Centre for Evidence Based Medicine 2011 foi usada para avaliações de qualidade. Mil e dezoito itens foram identificados na busca; Foram incluídos 26 registros na síntese qualitativa, que incluiu 6 revisões de literatura, 10 séries de casos ou estudos transversais, 4 relatos de casos e 6 descrições de intervenções. Dezessete dos 26 registros (65%) foram classificados como nível 5 no sistema de classificação da metodologia Oxford CBME, o restante foi no nível 4. As evidências geradas no COVID-19 e na oftalmologia até o momento são limitadas, embora isso seja compreensível dadas as circunstâncias. Tanto a possível presença de partículas virais em lágrimas e conjuntiva quanto o potencial de transmissão conjuntival permanecem controversos. As manifestações oculares não são frequentes e podem se assemelhar a infecção viral da superfície ocular. A maioria das recomendações baseia-se nas estratégias implementadas pelos países asiáticos durante surtos anteriores de coronavírus. Há necessidade de estudos aprofundados avaliando essas estratégias no cenário da SARS-CoV-2. Enquanto isso, os planos para a aplicação dessas medidas devem ser implementados com cautela, levando em consideração o contexto de cada país e submetidos a auditorias periódicas

    Powerful Radio Sources in the Southern Sky. II. A Swift X-Ray Perspective

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    We recently constructed the G4Jy-3CRE, a catalog of extragalactic radio sources based on the GLEAM 4-Jy (G4Jy) sample, with the aim of increasing the number of powerful radio galaxies and quasars with similar selection criteria to those of the revised release of the Third Cambridge Catalog (3CR). The G4Jy-3CRE consists of a total of 264 radio sources mainly visible from the Southern Hemisphere. Here, we present an initial X-ray analysis of 89 G4Jy-3CRE radio sources with archival X-ray observations from the Neil Gehrels Swift Observatory. We reduced a total of 624 Swift observations, for about 0.9 Ms of integrated exposure time. We found X-ray counterparts for 59 radio sources belonging to the G4Jy-3CRE, nine of them showing extended X-ray emission. The remaining 30 sources do not show any X-ray emission associated with their radio cores. Our analysis demonstrates that X-ray snapshot observations, even if lacking uniform exposure times, as those carried out with Swift, allow us to (i) verify and/or refine the host galaxy identification; (ii) discover the extended X-ray emission around radio galaxies of the intracluster medium when harbored in galaxy clusters, as the case of G4Jy 1518 and G4Jy 1664; and (iii) detect X-ray radiation arising from their radio lobes, as for G4Jy 1863

    Powerful Radio Sources in the Southern Sky. I. Optical Identifications

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    Since the early sixties, our view of radio galaxies and quasars has been drastically shaped by discoveries made thanks to observations of radio sources listed in the Third Cambridge Catalog and its revised version (3CR). However, the largest fraction of data collected to date on 3CR sources was performed with relatively old instruments, rarely repeated and/or updated. Importantly, the 3CR contains only objects located in the Northern Hemisphere, thus having limited access to new and innovative astronomical facilities. To mitigate these limitations, we present a new catalog of powerful radio sources visible from the Southern Hemisphere, extracted from the GLEAM 4 Jy (G4Jy) catalog and based on equivalent selection criteria as the 3CR. This new catalog, named G4Jy-3CRE, where the E stands for equivalent, lists a total of 264 sources at decl. below −5° and with 9 Jy limiting sensitivity at ∼178 MHz. We explored archival radio maps obtained with different surveys and compared them with optical images available in the Pan-STARRS, DES, and DSS databases to search for optical counterparts of their radio cores. We compared mid-infrared counterparts, originally associated in the G4Jy, with the optical ones identified here, and we present results of a vast literature search carried out to collect redshift estimates for all G4Jy-3CRE sources resulting in a total of 145 reliable z measurements
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