597 research outputs found

    Global reconstruction reduces the uncertainty of oceanic nitrous oxide emissions and reveals a vigorous seasonal cycle

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    Assessment of the global budget of the greenhouse gas nitrous oxide ([Formula: see text]O) is limited by poor knowledge of the oceanic [Formula: see text]O flux to the atmosphere, of which the magnitude, spatial distribution, and temporal variability remain highly uncertain. Here, we reconstruct climatological [Formula: see text]O emissions from the ocean by training a supervised learning algorithm with over 158,000 [Formula: see text]O measurements from the surface ocean-the largest synthesis to date. The reconstruction captures observed latitudinal gradients and coastal hot spots of [Formula: see text]O flux and reveals a vigorous global seasonal cycle. We estimate an annual mean [Formula: see text]O flux of 4.2 ± 1.0 Tg N[Formula: see text], 64% of which occurs in the tropics, and 20% in coastal upwelling systems that occupy less than 3% of the ocean area. This [Formula: see text]O flux ranges from a low of 3.3 ± 1.3 Tg N[Formula: see text] in the boreal spring to a high of 5.5 ± 2.0 Tg N[Formula: see text] in the boreal summer. Much of the seasonal variations in global [Formula: see text]O emissions can be traced to seasonal upwelling in the tropical ocean and winter mixing in the Southern Ocean. The dominant contribution to seasonality by productive, low-oxygen tropical upwelling systems (>75%) suggests a sensitivity of the global [Formula: see text]O flux to El Niño-Southern Oscillation and anthropogenic stratification of the low latitude ocean. This ocean flux estimate is consistent with the range adopted by the Intergovernmental Panel on Climate Change, but reduces its uncertainty by more than fivefold, enabling more precise determination of other terms in the atmospheric [Formula: see text]O budget

    From Big Society to Shared Society? Geographies of social cohesion and encounter in the UK’s National Citizen Service

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    This article explores and expands debates on the geographies of social cohesion and encounter, specifically in relation to young people and informal citizenship training. Three questions drive our agenda in this paper. First, how do certain youth spaces get enrolled into wider political discourses, functioning as geographical expressions of government visions to create a political legacy? Second, how are these spaces engineered and operate on-the-ground? Finally, how do young people understand their experiences of such spaces? To address these questions, we use the example of ‘National Citizen Service’ – a youth programme operating in England and Northern Ireland – to raise critical questions about the wider politics of spaces of informal education and attempts by the state to ‘make’ citizens and future neighbours. The article examines the rationale for this growing scheme, targeted at 15–17 year olds and designed to foster a ‘more cohesive, responsible and engaged society’. Drawing on original fieldwork with key architects, stakeholders and young people, we analyse the narratives that underlie NCS and its expansion – specifically around social cohesion and citizenship education. We explore the idea of ‘social mix’ as one of NCS’ guiding principles and its place as part of state narratives about the ‘Big Society’ and ‘Shared Society’

    D'Annunzio sulla scena lirica: libretto o "Poema"?

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    Australia Direct Action climate change policy relies on purchasing greenhouse gas abatement from projects undertaking approved abatement activities. Management of soil organic carbon (SOC) in agricultural soils is an approved activity, based on the expectation that land use change can deliver significant changes in SOC. However, there are concerns that climate, topography and soil texture will limit changes in SOC stocks. This work analyses data from 1482 sites surveyed across the major agricultural regions of Eastern Australia to determine the relative importance of land use vs. other drivers of SOC. Variation in land use explained only 1.4% of the total variation in SOC, with aridity and soil texture the main regulators of SOC stock under different land uses. Results suggest the greatest potential for increasing SOC stocks in Eastern Australian agricultural regions lies in converting from cropping to pasture on heavy textured soils in the humid regions

    Genetic Determinants of Circulating Sphingolipid Concentrations in European Populations

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    Sphingolipids have essential roles as structural components of cell membranes and in cell signalling, and disruption of their metabolism causes several diseases, with diverse neurological, psychiatric, and metabolic consequences. Increasingly, variants within a few of the genes that encode enzymes involved in sphingolipid metabolism are being associated with complex disease phenotypes. Direct experimental evidence supports a role of specific sphingolipid species in several common complex chronic disease processes including atherosclerotic plaque formation, myocardial infarction (MI), cardiomyopathy, pancreatic beta-cell failure, insulin resistance, and type 2 diabetes mellitus. Therefore, sphingolipids represent novel and important intermediate phenotypes for genetic analysis, yet little is known about the major genetic variants that influence their circulating levels in the general population. We performed a genome-wide association study (GWAS) between 318,237 single-nucleotide polymorphisms (SNPs) and levels of circulating sphingomyelin (SM), dihydrosphingomyelin (Dih-SM), ceramide (Cer), and glucosylceramide (GluCer) single lipid species (33 traits); and 43 matched metabolite ratios measured in 4,400 subjects from five diverse European populations. Associated variants (32) in five genomic regions were identified with genome-wide significant corrected p-values ranging down to 9.08 x 10(-66). The strongest associations were observed in or near 7 genes functionally involved in ceramide biosynthesis and trafficking: SPTLC3, LASS4, SGPP1, ATP10D, and FADS1-3. Variants in 3 loci (ATP10D, FADS3, and SPTLC3) associate with MI in a series of three German MI studies. An additional 70 variants across 23 candidate genes involved in sphingolipid-metabolizing pathways also demonstrate association (p = 10(-4) or less). Circulating concentrations of several key components in sphingolipid metabolism are thus under strong genetic control, and variants in these loci can be tested for a role in the development of common cardiovascular, metabolic, neurological, and psychiatric diseases

    Do we need to categorize it? Reflections on constituencies and quotas as tools for negotiating difference in the global food sovereignty convergence space

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    Convergence–as an objective and as a process–designates the coming together of different social actors across strategic, political, ideological, sectoral and geographic divides. In this paper, we analyze the global food sovereignty movement (GFSM) as a convergence space, with a focus on constituencies and quotas as tools to maintain diversity while facilitating convergence. We show how the use of constituencies and quotas has supported two objectives of the GFSM: alliances building and effective direct representation in global policy-making spaces. We conclude by pointing to some convergence challenges the GFSM faces as it expands beyond its agrarian origins.</p

    Effective implementation of research into practice: an overview of systematic reviews of the health literature

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    <p>Abstract</p> <p>Background</p> <p>The gap between research findings and clinical practice is well documented and a range of interventions has been developed to increase the implementation of research into clinical practice.</p> <p>Findings</p> <p>A review of systematic reviews of the effectiveness of interventions designed to increase the use of research in clinical practice. A search for relevant systematic reviews was conducted of Medline and the Cochrane Database of Reviews 1998-2009. 13 systematic reviews containing 313 primary studies were included. Four strategy types are identified: audit and feedback; computerised decision support; opinion leaders; and multifaceted interventions. Nine of the reviews reported on multifaceted interventions. This review highlights the small effects of single interventions such as audit and feedback, computerised decision support and opinion leaders. Systematic reviews of multifaceted interventions claim an improvement in effectiveness over single interventions, with effect sizes ranging from small to moderate. This review found that a number of published systematic reviews fail to state whether the recommended practice change is based on the best available research evidence.</p> <p>Conclusions</p> <p>This overview of systematic reviews updates the body of knowledge relating to the effectiveness of key mechanisms for improving clinical practice and service development. Multifaceted interventions are more likely to improve practice than single interventions such as audit and feedback. This review identified a small literature focusing explicitly on getting research evidence into clinical practice. It emphasizes the importance of ensuring that primary studies and systematic reviews are precise about the extent to which the reported interventions focus on changing practice based on research evidence (as opposed to other information codified in guidelines and education materials).</p

    The effect of the dual Src/Abl kinase inhibitor AZD0530 on Philadelphia positive leukaemia cell lines

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    Background Imatinib mesylate, a selective inhibitor of Abl tyrosine kinase, is efficacious in treating chronic myeloid leukaemia (CML) and Ph+ acute lymphoblastic leukaemia (ALL). However, most advanced-phase CML and Ph+ ALL patients relapse on Imatinib therapy. Several mechanisms of refractoriness have been reported, including the activation of the Src-family kinases (SFK). Here, we investigated the biological effect of the new specific dual Src/Abl kinase inhibitor AZD0530 on Ph+ leukaemic cells. Methods Cell lines used included BV173 (CML in myeloid blast crisis), SEM t(4;11), Ba/F3 (IL-3 dependent murine pro B), p185Bcr-Abl infected Ba/F3 cells, p185Bcr-Abl mutant infected Ba/F3 cells, SupB15 (Ph+ ALL) and Imatinib resistant SupB15 (RTSupB15) (Ph+ ALL) cells. Cells were exposed to AZD0530 and Imatinib. Cell proliferation, apoptosis, survival and signalling pathways were assessed by dye exclusion, flow cytometry and Western blotting respectively. Results AZD0530 specifically inhibited the growth of, and induced apoptosis in CML and Ph+ ALL cells in a dose dependent manner, but showed only marginal effects on Ph- ALL cells. Resistance to Imatinib due to the mutation Y253F in p185Bcr-Abl was overcome by AZD0530. Combination of AZD0530 and Imatinib showed an additive inhibitory effect on the proliferation of CML BV173 cells but not on Ph+ ALL SupB15 cells. An ongoing transphosphorylation was demonstrated between SFKs and Bcr-Abl. AZD0530 significantly down-regulated the activation of survival signalling pathways in Ph+ cells, resistant or sensitive to Imatinib, with the exception of the RTSupB15. Conclusion Our results indicate that AZD0530 targets both Src and Bcr-Abl kinase activity and reduces the leukaemic maintenance by Bcr-Abl
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