5,637 research outputs found

    Evaluation of a Bayesian Algorithm to Detect Burned Areas in the Canary Islands’ Dry Woodlands and Forests Ecoregion Using MODIS Data

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    Burned Area (BA) is deemed as a primary variable to understand the Earth’s climate system. Satellite remote sensing data have allowed for the development of various burned area detection algorithms that have been globally applied to and assessed in diverse ecosystems, ranging from tropical to boreal. In this paper, we present a Bayesian algorithm (BY-MODIS) that detects burned areas in a time series of Moderate Resolution Imaging Spectroradiometer (MODIS) images from 2002 to 2012 of the Canary Islands’ dry woodlands and forests ecoregion (Spain). Based on daily image products MODIS, MOD09GQ (250 m), and MOD11A1 (1 km), the surface spectral reflectance and the land surface temperature, respectively, 10 day composites were built using the maximum temperature criterion. Variables used in BY-MODIS were the Global Environment Monitoring Index (GEMI) and Burn Boreal Forest Index (BBFI), alongside the NIR spectral band, all of which refer to the previous year and the year the fire took place in. Reference polygons for the 14 fires exceeding 100 hectares and identified within the period under analysis were developed using both post-fire LANDSAT images and official information from the forest fires national database by the Ministry of Agriculture and Fisheries, Food and Environment of Spain (MAPAMA). The results obtained by BY-MODIS can be compared to those by official burned area products, MCD45A1 and MCD64A1. Despite that the best overall results correspond to MCD64A1, BY-MODIS proved to be an alternative for burned area mapping in the Canary Islands, a region with a great topographic complexity and diverse types of ecosystems. The total burned area detected by the BY-MODIS classifier was 64.9% of the MAPAMA reference data, and 78.6% according to data obtained from the LANDSAT images, with the lowest average commission error (11%) out of the three products and a correlation (R2) of 0.82. The Bayesian algorithm—originally developed to detect burned areas in North American boreal forests using AVHRR archival data Long-Term Data Record—can be successfully applied to a lower latitude forest ecosystem totally different from the boreal ecosystem and using daily time series of satellite images from MODIS with a 250 m spatial resolution, as long as a set of training areas adequately characterising the dynamics of the forest canopy affected by the fire is defined

    Why do we choose to address health 2020?

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    What can we predict for 2020? Solar and lunar eclipses? Without a doubt. Climate change? Most likely. Rising sea levels? Signs point to yes. Beyond that, however, in the world of human events, it is best to be cautious. In the field of health and medicine (or anywhere else, for that matter), no one predicted the most important discoveries of the twentieth century. Economists were no more successful in foreseeing financial or economic crises. The pundits did not forecast any of the recent wars, disruptions or even the recent Arab Spring movements indeed, political experts turned out to be only slightly more accurate than dart-throwing chimpanzees in divining what was in store for the future.1 As the World Health Organization (WHO) and the wider scientific community looked to East Asia in anticipation of the next outbreak of H5N1, the influenza H1N1 pandemic took hold in Mexico. Tsunamis, volcanic eruptions, earthquakes, drug scandals, outbreaks of emerging diseases and political disruptions are notoriously unpredictable, as Nassim Nicholas Taleb brilliantly highlighted in his book The Black Swan

    Strong versus weak embodiment: Spatial iconicity in physical, abstract, and social semantic categories

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    Background Perceptual and action systems seem to be related to complex cognitive processes, but the scope of grounded or embodied cognition has been questioned. Zwaan and Yaxley (2003) proposed that cognitive processes of making semantic relatedness judgments can be facilitated when word pairs are presented in ways that their referents maintain their iconic configuration rather than their reverse-iconic configuration (the spatial iconicity effect). This effect has been observed in different semantic categories using specific experiments, but it is known that embodiment is highly dependent on task demands. Method The present study analyzed the spatial iconicity effect in three semantic categories (physical, abstract, and social) using the same experimental criteria to determine the scope of embodied cognition. In this reaction-time experiment, 75 participants judged the semantic relatedness of 384 word pairs whose experimental items were presented in their iconic or reverse-iconic configurations. Results Two mixed-effects models with crossed random effects revealed that the interaction between word meaning and spatial position was present only for physical concepts but neither for abstract nor social concepts. Conclusions Within the framework of strong and weak embodiment theories, the data support weak embodiment theory as the most explicative oneThe work reported in this article was supported by Grant PSI2013-47219-P from the Ministry of Economic and Competitiveness (MINECO) of Spai

    Genomic analysis of eight native plasmids of the phytopathogen Pseudomonas syringae

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    Comunicación a conferenciaThe pPT23A family of plasmids (PFPs) appears to be indigenous to the plant pathogen Pseudomonas syringae and these plasmids are widely distributed and widely transferred among pathovars of P. syringae and related species. PFPs are sources of accessory genes for their hosts that can include genes important for virulence and epiphytic colonization of plant leaf surfaces. Further understanding of the evolution of the pPT23A plasmid family and the role of these plasmids in P. syringae biology and pathogenesis, requires the determination and analysis of additional complete, closed plasmid genome sequences. Therefore, our main objective was to obtain complete genome sequences from PFPs from three different P. syringae pathovars and perform a comparative genomic analysis. In this work plasmid DNA isolation, purification by CsCl-EtBr gradients, and sequencing using 454 platform, were used to obtain the complete sequence of P. syringae plasmids. Different bioinformatic tools were used to analyze the plasmid synteny, to identify virulence genes (i.e. type 3 effectors) and to unravel the evolutionary history of PFPs. Our sequence analysis revealed that PFPs from P. syringae encode suites of accessory genes that are selected at different levels (universal, interpathovar and intrapathovar). The conservation of type IVSS encoding conjugation functions also contributes to the distribution of these plasmids within P. syringae populations. Thus, this study contributes to unravel the genetic basis of the role of PFPs in different P. syringae lifestyles.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

    Isolation, characterization and selection of bacterial isolates from a suppressive soil with beneficial traits to plants

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    Backgrounds This study focused on the characterization and selection of bacterial strains obtained from a suppressive soil displaying antifungal activity against the soilborne phytopathogenic fungi Rosellinia necatrix. Bacterial profile from this suppressive soil were first obtained by 16S rRNA gene sequencing, revealing a significant increase in the bacterial class Gammaproteobacteria, especially in some antagonistic representatives of Pseudomonas spp. Objectives To obtain and characterize a collection of 246 bacterial isolates obtained from this suppressive soil, in order to identify new strains with antifungal activity against fungal phytopathogens. Methods To obtain the bacterial collection, we performed an isolation on a selective medium for Pseudomonas-like microorganisms. Further characterization tests were used in order to analyse the bacterial collection, including identification of the general metabolic profile of glucose, the profiling of antifungals produced, including both the putative production of antifungal compounds and lytic exoenzymes, and the evaluation of traits related with beneficial effects on plants. Conclusions A final selection of representative strains resulted in antifungal isolates belonging to the genus Pseudomonas, but also some representatives of the genera Serratia and Stenotrophomonas. These selected strains were tested for plant protection by an in vivo experiment using avocado and wheat plants challenged by the pathogen R. necatrix, showing all of them an antifungal ability and plant disease protection. Pseudomonas-like strains isolated from suppressive soils constitute an excellent source for novel microbial biocontrol agents against soilborne fungal pathogens. This work was supported by grant AGL2014-52518-C2-1-R. Carmen Vida and Sandra Tienda are supported by a PhD fellowship from the FPI program of the Spanish Government.This work was supported by grant AGL2014-52518-C2-1-R. Carmen Vida and Sandra Tienda are supported by a PhD fellowship from the FPI program of the Spanish Government; Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

    El triángulo del fraude y sus efectos sobre la integridad laboral

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    Los expertos determinaron que para que se materialice el fraude deben existir el poder, la oportunidad de cometerlo y la racionalización (D. Cressey (1961)). Estos tres puntos importantes se conocen como el triángulo del fraude. El propósito principal de este trabajo de investigación fue detectar e identificar si hay relación entre el nivel gerencial y las dimensiones del fraude. Para este trabajo de investigación se entregó un cuestionario para ser cumplimentado por gerentes que trabajan en el área de la banca hipotecaria de San Juan, Puerto Rico. Se utilizó la prueba no paramétrica Kendall Tau para correlacionar las variables de la investigación. De esta misma forma se comprobaron que las características del fraude asociadas a la dimensión de la oportunidad, están determinadas por el nivel gerencial en una organización. Con este razonamiento estadístico relacionamos las tres dimensiones del fraude: poder vs. oportunidad, poder vs. racionalización y oportunidad vs. racionalización. Sólo en esta última relación, hay evidencia para rechazar la hipótesis nula que establece que las características del fraude asociadas al ángulo de oportunidad, no están relacionadas a la racionalización del individuo que pretende o comete fraude
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