1,883 research outputs found

    Determinação da aptidão biogeofísica do território EUROACE para a utilização agroflorestal

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    É consensual que a escolha dos usos mais adequados às aptidões edafo-climáticas, complementada com critérios socioeconómicos, promove uma utilização sustentável dos espaços rurais. Existem, no entanto, diferentes metodologias utilizadas para a definição da capacidade e potencialidade do solo para a implementação de usos agroflorestais ou manutenção de ecossistemas naturais e seminaturais, nomeadamente culturas agrícolas, povoamentos florestais, territórios agro-silvo-pastoris e áreas prioritárias para a conservação da natureza. Muitas dessas metodologias recorrem a sistemas de apoio à decisão, baseados na análise espacial multicritério. Neste estudo pretendeu-se determinar os diferentes níveis de aptidão para a utilização agroflorestal no território transfronteiriço que abrange o Alentejo, Extremadura e o Centro (Euro-região EUROACE). Para o efeito recorreu-se a um conjunto de variáveis edáficas e topográficas. Foram igualmente incorporadas as condicionantes legais e a ocupação do solo. A avaliação da aptidão foi efetuada com recurso ao método de análise espacial multicritério Analytic Hierarchy Process (AHP). O resultado obtido com esta metodologia, confrontado com a matriz de uso existente, permite identificar as áreas onde a ocupação e gestão está de acordo com a aptidão do espaço, bem como as áreas onde o uso deverá ser alvo de uma reconversão ou apenas a uma alteração de modo de gestão

    Influence of conservation tillage and soil water content on crop yield in dryland compacted alfisol of Central Chile

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    Chilean dryland areas of the Mediterranean climate region are characterized by highly degraded and compacted soils, which require the use of conservation tillage systems to mitigate water erosion as well as to improve soil water storage. An oat (Avena sativa L. cv. Supernova-INIA) - wheat (Triticum aestivum L. cv. Pandora-INIA) crop rotation was established under the following conservation systems: no tillage (Nt), Nt + contour plowing (Nt+Cp), Nt + barrier hedge (Nt+Bh), and Nt + subsoiling (Nt+Sb), compared to conventional tillage (Ct) to evaluate their influence on soil water content (SWC) in the profile (10 to 110 cm depth), the soil compaction and their interaction with the crop yield. Experimental plots were established in 2007 and lasted 3 yr till 2009 in a compacted Alfisol. At the end of the growing seasons, SWC was reduced by 44 to 51% in conservation tillage systems and 60% in Ct. Soil water content had a significant (p < 0.05) interaction with tillage system and depth; Nt+Sb showed lower SWC between 10 to 30 cm, but higher and similar to the rest between 50 to 110 cm except for Ct. Although, SWC was higher in conservation tillage systems, the high values on soil compaction affected yield. No tillage + subsoiling reduced soil compaction and had a significant increment of grain yield (similar to Ct in seasons 2008 and 2009). These findings show us that the choice of conservation tillage in compacted soils of the Mediterranean region needs to improve soil structure to obtain higher yields and increment SWC

    Natural variation in stress response gene activity in the allopolyploid Arabidopsis suecica

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    Background Allopolyploids contain genomes composed of more than two complete sets of chromosomes that originate from at least two species. Allopolyploidy has been suggested as an important evolutionary mechanism that can lead to instant speciation. Arabidopsis suecica is a relatively recent allopolyploid species, suggesting that its natural accessions might be genetically very similar to each other. Nonetheless, subtle phenotypic differences have been described between different geographic accessions of A. suecica grown in a common garden. Results To determine the degree of genomic similarity between different populations of A. suecica, we obtained transcriptomic sequence, quantified SNP variation within the gene space, and analyzed gene expression levels genome-wide from leaf material grown in controlled lab conditions. Despite their origin from the same progenitor species, the two accessions of A. suecica used in our study show genomic and transcriptomic variation. We report significant gene expression differences between the accessions, mostly in genes with stress-related functions. Among the differentially expressed genes, there are a surprising number of homoeologs coordinately regulated between sister accessions. Conclusions Many of these homoeologous genes and other differentially expressed genes affect transpiration and stomatal regulation, suggesting that they might be involved in the establishment of the phenotypic differences between the two accessions

    HAG1 and SWI3A/B control of male germ line development in P. patens suggests conservation of epigenetic reproductive control across land plants

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    Bryophytes as models to study the male germ line: loss-of-function mutants of epigenetic regulators HAG1 and SWI3a/b demonstrate conserved function in sexual reproduction

    Regulation of membrane ruffling by polarized STIM1 and ORAI1in cortactin-rich domains

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    La movilidad celular y la migración requieren la reorganización del citoesqueleto cortical en el borde principal de las células y la entrada de Ca2 + extracelular es esencial para esta reorganización. Sin embargo, la naturaleza molecular de los reguladores de esta vía es desconocida. Este trabajo contribuye a comprender el papel de STIM1 y ORAI1 en la promoción de la ondulación de la membrana al mostrar que la fosfo-STIM1 se localiza en el borde principal de las células, y que tanto phospho-STIM1 como ORAI1 se localizan conjuntamente con la cortactina (CTTN), un regulador del citoesqueleto en las zonas de rizo de la membrana. Las líneas celulares STIM1-KO y ORAI1-KO se generaron mediante la edición del genoma CRISPR / Cas9 en células U2OS. En ambos casos, las células KO presentaron una reducción notable de la entrada de Ca2 + operada por el almacén (SOCE) que se rescató mediante la expresión de STIM1-mCherry y ORAI1-mCherry. Estos resultados demostraron que SOCE regula la deformación de la membrana en el borde anterior de las células. Por otra parte, ORAI1 endógeno y ORAI1-GFP sobreexpresado coinmuno precipitado con CTTN endógeno. Este último resultado, además del fenotipo de las células KO, la preservación de la co-localización de ORAI1-CTTN durante el fruncido, y la inhibición de la rizo de la membrana por parte del inhibidor del canal de Ca2 + SKF96365, apoya aún más un vínculo funcional entre el SOCE y el fruncido de la membrana.Cell motility and migration requires the reorganization of the cortical cytoskeleton at the leading edge of cells and extracellular Ca2+ entry is essential for this reorganization. However the molecular nature of the regulators of this pathway is unknown. This work contributes to understanding the role of STIM1 and ORAI1 in the promotion of membrane ruffling by showing that phospho-STIM1 localizes at the leading edge of cells, and that both phospho-STIM1 and ORAI1 co-localize with cortactin (CTTN), a regulator of the cytoskeleton at membrane ruffling areas. STIM1-KO and ORAI1-KO cell lines were generated by CRISPR/Cas9 genome editing in U2OS cells. In both cases, KO cells presented a notable reduction of store-operated Ca2+ entry (SOCE) that was rescued by expression of STIM1-mCherry and ORAI1-mCherry. These results demonstrated that SOCE regulates membrane ruffling at the leading edge of cells. Moreover, endogenous ORAI1 and overexpressed ORAI1-GFP co-immuno precipitated with endogenous CTTN. This latter result, in addition to the KO cells’ phenotype, the preservation of ORAI1-CTTN co-localization during ruffling, and the inhibition of membrane ruffling g by the Ca2+- channel inhibitor SKF96365, further supports a functional link between SOCE and membrane ruffling.• Ministerio de Economía y Competitividad y Fondo Social Europeo. Becas BFU2011-22798 y BFU2014-52401-P, para Francisco Javier Martín Romero • Consejo de Investigación Médica. Beca MC_UU_12016 / 2, para Darío R. Alessi • Ministerio de Economía y Competitividad. Beca BES-2012-052061, para Aida María López Guerrero • Gobierno de Extremadura. Ayuda PD10081, para Patricia Tomás Martín • Ministerio de Educación, Cultura y Deporte. Beca FPU13 / 03430, para Carlos Pascual Caro • Consejo de Investigación Médica. Ayuda MR / K015869 / 1, para Graeme Ball • EMBO. Beca ASTF-311-2014, para Eulalia Pozo Guisado • Ministerio de Educación, Cultura Española y Deporte. Beca PRX14 / 00176, para Francisco Javier Martín RomeropeerReviewe

    The Sol Genomics Network (SGN)&#8212;from genotype to phenotype to breeding

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    The Sol Genomics Network (SGN, http://solgenomics.net) is a web portal with genomic and phenotypic data, and analysis tools for the Solanaceae family and close relatives. SGN hosts whole genome data for an increasing number of Solanaceae family members including tomato, potato, pepper, eggplant, tobacco and Nicotiana benthamiana. The database also stores loci and phenotype data, which researchers can upload and edit with user-friendly web interfaces. Tools such as BLAST, GBrowse and JBrowse for browsing genomes, expression and map data viewers, a locus community annotation system and a QTL analysis tools are available. A new tool was recently implemented to improve Virus-Induced Gene Silencing (VIGS) constructs called the SGN VIGS tool. With the growing genomic and phenotypic data in the database, SGN is now advancing to develop new web-based breeding tools and implement the code and database structure for other species or clade-specific databases

    Linezolid-induced lactic acidosis in two liver transplant patients with the mitochondrial DNA A2706G polymorphism

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    Mitochondrial toxicity has been recently suggested to be the underlying mechanism of long-term linezolid-associated toxicity in patients with 16S rRNA genetic polymorphisms. Here, we report for the first time two cases of lactic acidosis due to long-term linezolid exposure in liver transplant recipients who presented an A2706G mitochondrial DNA polymorphism

    Epidemiology, patterns of care, and mortality for patients with acute respiratory distress syndrome in intensive care units in 50 countries

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    IMPORTANCE: Limited information exists about the epidemiology, recognition, management, and outcomes of patients with the acute respiratory distress syndrome (ARDS). OBJECTIVES: To evaluate intensive care unit (ICU) incidence and outcome of ARDS and to assess clinician recognition, ventilation management, and use of adjuncts-for example prone positioning-in routine clinical practice for patients fulfilling the ARDS Berlin Definition. DESIGN, SETTING, AND PARTICIPANTS:The Large Observational Study to Understand the Global Impact of Severe Acute Respiratory Failure (LUNG SAFE) was an international, multicenter, prospective cohort study of patients undergoing invasive or noninvasive ventilation, conducted during 4 consecutive weeks in the winter of 2014 in a convenience sample of 459 ICUs from 50 countries across 5 continents. EXPOSURES:Acute respiratory distress syndrome. MAIN OUTCOMES AND MEASURES: The primary outcome was ICU incidence of ARDS. Secondary outcomes included assessment of clinician recognition of ARDS, the application of ventilatory management, the use of adjunctive interventions in routine clinical practice, and clinical outcomes from ARDS. RESULTS: Of 29,144 patients admitted to participating ICUs, 3022 (10.4%) fulfilled ARDS criteria. Of these, 2377 patients developed ARDS in the first 48 hours and whose respiratory failure was managed with invasive mechanical ventilation. The period prevalence of mild ARDS was 30.0% (95% CI, 28.2%-31.9%); of moderate ARDS, 46.6% (95% CI, 44.5%-48.6%); and of severe ARDS, 23.4% (95% CI, 21.7%-25.2%). ARDS represented 0.42 cases per ICU bed over 4 weeks and represented 10.4% (95% CI, 10.0%-10.7%) of ICU admissions and 23.4% of patients requiring mechanical ventilation. Clinical recognition of ARDS ranged from 51.3% (95% CI, 47.5%-55.0%) in mild to 78.5% (95% CI, 74.8%-81.8%) in severe ARDS. Less than two-thirds of patients with ARDS received a tidal volume 8 of mL/kg or less of predicted body weight. Plateau pressure was measured in 40.1% (95% CI, 38.2-42.1), whereas 82.6% (95% CI, 81.0%-84.1%) received a positive end-expository pressure (PEEP) of less than 12 cm H2O. Prone positioning was used in 16.3% (95% CI, 13.7%-19.2%) of patients with severe ARDS. Clinician recognition of ARDS was associated with higher PEEP, greater use of neuromuscular blockade, and prone positioning. Hospital mortality was 34.9% (95% CI, 31.4%-38.5%) for those with mild, 40.3% (95% CI, 37.4%-43.3%) for those with moderate, and 46.1% (95% CI, 41.9%-50.4%) for those with severe ARDS. CONCLUSIONS AND RELEVANCE: Among ICUs in 50 countries, the period prevalence of ARDS was 10.4% of ICU admissions. This syndrome appeared to be underrecognized and undertreated and associated with a high mortality rate. These findings indicate the potential for improvement in the management of patients with ARDS

    Observation of Pulsed Gamma-rays Above 25 GeV from the Crab Pulsar with MAGIC

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    One fundamental question about pulsars concerns the mechanism of their pulsed electromagnetic emission. Measuring the high-end region of a pulsar's spectrum would shed light on this question. By developing a new electronic trigger, we lowered the threshold of the Major Atmospheric gamma-ray Imaging Cherenkov (MAGIC) telescope to 25 GeV. In this configuration, we detected pulsed gamma-rays from the Crab pulsar that were greater than 25 GeV, revealing a relatively high cutoff energy in the phase-averaged spectrum. This indicates that the emission occurs far out in the magnetosphere, hence excluding the polar-cap scenario as a possible explanation of our measurement. The high cutoff energy also challenges the slot-gap scenario.Comment: Slight modification of the analysis: Fitting a more general function to the combined data set of COMPTEL, EGRET and MAGIC. Final result and conclusion is unchange
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