1,261 research outputs found

    Investigation of EMIC wave scattering as the cause for the BARREL 17 January 2013 relativistic electron precipitation event: A quantitative comparison of simulation with observations

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    Abstract Electromagnetic ion cyclotron (EMIC) waves were observed at multiple observatory locations for several hours on 17 January 2013. During the wave activity period, a duskside relativistic electron precipitation (REP) event was observed by one of the Balloon Array for Radiation belt Relativistic Electron Losses (BARREL) balloons and was magnetically mapped close to Geostationary Operational Environmental Satellite (GOES) 13. We simulate the relativistic electron pitch angle diffusion caused by gyroresonant interactions with EMIC waves using wave and particle data measured by multiple instruments on board GOES 13 and the Van Allen Probes. We show that the count rate, the energy distribution, and the time variation of the simulated precipitation all agree very well with the balloon observations, suggesting that EMIC wave scattering was likely the cause for the precipitation event. The event reported here is the first balloon REP event with closely conjugate EMIC wave observations, and our study employs the most detailed quantitative analysis on the link of EMIC waves with observed REP to date. Key PointsQuantitative analysis of the first balloon REP with closely conjugate EMIC wavesOur simulation suggests EMIC waves to be a viable cause for the REP eventThe adopted model is proved to be applicable to simulating the REP event

    Laparoscopic nephrectomy for ex-vivo correction of renal artery aneurism and auto transplant

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    INTRODUCTION AND OBJECTIVES: Renal artery aneurism are a rare condition, with a prevalence of 0.09% of the population. The outcomes and clinical management of this patients depend on the presence of symptoms and subsequent risk of rupture. Most patients are managed by endovascular techniques, but difficult cases may present a challenge to urologists. METHODS: We present a case of a 35 year old female, history of high blood pressure with the diagnosis of a left renal artery aneurism with a diameter of 27 mm. The patient was evaluated by vascular surgery, was unsuitable for endovascular treatment and was submitted to a laparoscopic left nephrectomy with correction of the aneurism ex-vivo and the kidney was transplanted to the left iliac region. RESULTS: Operative time was 150 minutes and the warm ischemia time was 160 seconds. Blood loss was estimated in 80 mL with a hematocrit drop of 2% post operative. Drainage and vesical catheter were removed at day 2 and 6 post-operative, respectively. Post operative creatinine clearance was comparable to the pre operative (Post - 95 vs. Pre - 98 mL/min/1.73m2) The follow up is 15 months and the patients has a functioning kidney and had a normalization of the blood pressure. CONCLUSIONS: In experienced centers, laparoscopic nephrectomy with subsequent autotransplantion can be a safe and effective option in the management of specific conditions. This case presents a possible way to treat renal artery aneurisms that can’t be managed by endovascular procedures

    NG2 antigen is involved in leukemia invasiveness and central nervous system infiltration in MLL-rearranged infant B-ALL

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    Mixed-lineage leukemia (MLL)-rearranged (MLLr) infant B-cell acute lymphoblastic leukemia (iMLLr-B-ALL) has a dismal prognosis and is associated with a pro-B/mixed phenotype, therapy refractoriness and frequent central nervous system (CNS) disease/relapse. Neuron-glial antigen 2 (NG2) is specifically expressed in MLLr leukemias and is used in leukemia immunophenotyping because of its predictive value for MLLr acute leukemias. NG2 is involved in melanoma metastasis and brain development; however, its role in MLL-mediated leukemogenesis remains elusive. Here we evaluated whether NG2 distinguishes leukemia-initiating/propagating cells (L-ICs) and/or CNS-infiltrating cells (CNS-ICs) in iMLLr-B-ALL. Clinical data from the Interfant cohort of iMLLr-B-ALL demonstrated that high NG2 expression associates with lower event-free survival, higher number of circulating blasts and more frequent CNS disease/relapse. Serial xenotransplantation of primary MLL-AF4 + leukemias indicated that NG2 is a malleable marker that does not enrich for L-IC or CNS-IC in iMLLr-B-All. However, NG2 expression was highly upregulated in blasts infiltrating extramedullar hematopoietic sites and CNS, and specific blockage of NG2 resulted in almost complete loss of engraftment. Indeed, gene expression profiling of primary blasts and primografts revealed a migratory signature of NG2 + blasts. This study provides new insights on the biology of NG2 in iMLLr-B-ALL and suggests NG2 as a potential therapeutic target to reduce the risk of CNS disease/relapse and to provide safer CNS-directed therapies for iMLLr-B-ALL

    Progress on agriculture in the UN climate talks: How COP21 can ensure a food-secure future

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    Agriculture, and consequently food security and livelihoods, is already being affected by climate change, according to latest science from the IPCC (Porter et al. 2014). The IPCC agrees that the world needs to produce at least 50% more food than we do today in order to meet the goal of feeding a projected 9 billion people by 2050. This must be achieved in the face of climatic variability and change, growing constraints on water and land for crops and livestock, and declining wild capture fishery stocks. Although the protection of food security lies within the core objective of the United Nations Framework Convention on Climate Change (UNFCCC) (Article 2), formal arrangements for addressing agriculture within COP21 are unlikely. CGIAR would welcome the strengthening of aspirations for food security through action on mitigation and adaptation within a new agreement. We recognise that the new climate agreement is unlikely to be prescriptive about how adaptation in agriculture is supported and how agriculture might contribute to emission cuts. These issues are addressed within countries’ INDCs and determined at national level

    A 6 part action plan to transform food systems under climate change, Creative actions to accelerate progress towards the SDGs

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    If we are to achieve the Sustainable Development Goals (SDGs) related to poverty, climate change and food and nutrition security, the agricultural development community (research institutions, private sector, farmer organizations, national and international agencies) will have to work collectively with the world’s 700 million small-scale farmers by 2030 to transform the way food is produced, processed and consumed. Never before have we faced such ambitious goals

    A 6 part action plan to transform food systems under climate change, Creative actions to accelerate progress towards the SDGs

    Get PDF
    If we are to achieve the Sustainable Development Goals (SDGs) related to poverty, climate change and food and nutrition security, the agricultural development community (research institutions, private sector, farmer organizations, national and international agencies) will have to work collectively with the world’s 700 million small-scale farmers by 2030 to transform the way food is produced, processed and consumed. Never before have we faced such ambitious goals

    Assessing variability in the ratio of metal concentrations measured by DGT-type passive samplers and spot sampling in European seawaters

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    The current study evaluates the effect of seawater physico-chemical characteristics on the relationship between the concentration of metals measured by Diffusive Gradients in Thin films (DGT) passive samplers (i.e., DGT-labile concentration) and the concentrations measured in discrete water samples. Accordingly, Inductively Coupled Plasma Mass Spectrometry (ICP-MS) was used to measure the total dissolved metal concentrations in the discrete water samples and the labile metal concentrations obtained by DGT samplers; additionally, lead and cadmium conditional labile fractions were determined by Anodic Stripping Voltammetry (ASV) and total dissolved nickel was measured by Cathodic Stripping Voltammetry (CSV). It can be concluded that, in general, the median ratios of DGT/ICP and DGT/ASV(CSV) were lower than 1, except for Ni (median ratio close to 1) and Zn (higher than 1). This indicates the importance of speciation and time-integrated concentrations measured using passive sampling techniques, which is in line with the WFD suggestions for improving the chemical assessment of waterbodies. It is the variability in metal content in waters rather than environmental conditions to which the variability of the ratios can be attributed. The ratios were not significantly affected by the temperature, salinity, pH, oxygen, DOC or SPM, giving a great confidence for all the techniques used. Within a regulatory context such as the EU Water Framework Directive this is a great advantage, since the simplicity of not needing to use corrections to minimize the effects of environmental variables could help in implementing DGTs within monitoring networks
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