1,248 research outputs found

    The Cosmic Ray p+He energy spectrum in the 3-3000 TeV energy range measured by ARGO-YBJ

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    The ARGO-YBJ experiment is a full coverage air shower detector operated at the Yangbajing International Cosmic Ray Observatory. The detector has been in stable data taking in its full configuration since November 2007 to February 2013. The high altitude and the high segmentation and spacetime resolution offer the possibility to explore the cosmic ray energy spectrum in a very wide range, from a few TeV up to the PeV region. The high segmentation allows a detailed measurement of the lateral distribution, which can be used in order to discriminate showers produced by light and heavy elements. In this work we present the measurement of the cosmic ray light component spectrum in the energy range 3-3000 TeV. The analysis has been carried out by using a two-dimensional unfolding method based on the Bayes' theorem.Comment: Talk given at RICAP14 conferenc

    Dose of colistin. a work in progress?

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    We thank Rashid and colleagues [1] and Honoré and colleagues [2] for their comments regarding our article on risk factors for acute kidney injury in pa- tients receiving colistin or other nephrotoxic antimi- crobials [3]. It is correct that we did not specifically report urine output in the text, but it was obviously included in the RIFLE (Risk, Injury, Failure, Loss of kidney function, and End-stage kidney disease) criteria reported in Table two [3]

    Clinical and Pathophysiological Insights Into Immunological Mediated Glomerular Diseases in Childhood

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    The kidney is often the target of immune system dysregulation in the context of primary or systemic disease. In particular, the glomerulus represents the anatomical entity most frequently involved, generally as the expression of inflammatory cell invasion or circulant or in situ immune-complex deposition. Glomerulonephritis is the most common clinical and pathological manifestation of this involvement. There are no universally accepted classifications for glomerulonephritis. However, recent advances in our understanding of the pathophysiological mechanisms suggest the assessment of immunological features, biomarkers, and genetic analysis. At the same time, more accurate and targeted therapies have been developed. Data on pediatric glomerulonephritis are scarce and often derived from adult studies. In this review, we update the current understanding of the etiologic events and genetic factors involved in the pathogenesis of pediatric immunologically mediated primitive forms of glomerulonephritis, together with the clinical spectrum and prognosis. Possible new therapeutic targets are also briefly discussed

    Atmospheric neutrino spectrum reconstruction with JUNO

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    The atmospheric neutrino flux represents a continuous source that can be exploited to infer properties about Cosmic Rays and neutrino oscillation physics. The JUNO observatory, a 20 kt liquid scintillator currently under construction in China, will be able to detect atmospheric neutrinos , given the large fiducial volume and the excellent energy resolution. The light produced in neutrino interactions will be collected by a double-system of photosensors: about 18.000 20" PMTs and about 25.000 3" PMTs. The rock overburden above the experimental hall is around 700 m and the experiment is expected to complete construction in 2021. In this study, the JUNO performances in reconstructing the atmospheric neutrino spectrum have been evaluated. The different time evolution of scintillation light on the PMTs allows to discriminate the flavor of the primary neutrinos. To reconstruct the time pattern of events, the signals from 3" PMTs only have been used, because of the small time resolution. A probabilistic unfolding method has been used, in order to infer the primary neutrino energy spectrum by looking at the detector output. The simulated spectrum has been reconstructed between 100 MeV and 10 GeV, showing a great potential of the detector in the atmospheric low energy region. The uncertainties on the final flux, including both statistic and the systematic contributions, range between 10% and 25%, with the best performances obtained at the GeV.Comment: 7 pages, 7 figures. Proceeding for a parallel talk at the 2019 EPS-HEP Conference. arXiv admin note: text overlap with arXiv:1901.1034

    A Machine Learning-Based Method for Modelling a Proprietary SO2 Removal System in the Oil and Gas Sector

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    The aim of this study is to develop a model for a proprietary SO2 removal technology by using machine learning techniques and, more specifically, by exploiting the potentialities of artificial neural networks (ANNs). This technology is employed at the Eni oil and gas treatment plant in southern Italy. The amine circulating in this unit, that allows for a reduction in the SO2 concentration in the flue gases and to be compliant with the required specifications, is a proprietary solvent; thus, its composition is not publicly available. This has led to the idea of developing a machine learning (ML) algorithm for the unit description, with the objective of becoming independent from the licensor and more flexible in unit modelling. The model was developed in MatLab® by implementing ANNs and the aim was to predict three targets, namely the flow rate of SO2 that goes to the Claus unit, the emissions of SO2, and the flow rate of steam sent to the regenerator reboiler. These represent, respectively, the two physical outputs of the unit and a proxy variable of the amine quality. Three different models were developed, one for each target, that employed the Levenberg–Marquardt optimization algorithm. In addition, the ANN topology was optimized case by case. From the analysis of the results, it emerged that with a purely data-driven technique, the targets can be predicted with good accuracy. Therefore, this model can be employed to better manage the SO2 removal system, since it allows for the definition of an optimal control strategy and the maximization of the plant’s productivity by not exceeding the process constraints

    Foot Posture Index Does Not Correlate with Dynamic Foot Assessment Performed via Baropodometric Examination: A Cross-Sectional Study

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    Background. Clinicians employ foot morphology assessment to evaluate the functionality of the method and anticipate possible injuries. This study aims to correlate static foot posture and the dynamic barefoot evaluation in a sample of healthy adult participants. Methods. The foot posture was evaluated using the Foot Posture Index-6 (FPI-6) and the dynamics were evaluated through baropodometric examination. Two operators independently assessed the participants’ foot posture through FPI-6, and then a dynamic evaluation was performed by asking them to walk 8 times across a platform. One hundred participants (mean age: 32.15 ± 7.49) were enrolled. Results. The inter-rater agreement between the two assessors was found to be excellent. The majority of the feet belonged to the 0 < FPI < 4 class (32%), followed by the 4 < FPI < 8 (31%) and the FPI > 8 ranges (19.5%). Our “area of contact” analysis showed a significant poor correlation between FPI and total foot, midfoot, and the second metatarsophalangeal joint (MTPJ) (−0.3 < r < 0). Regarding “force” parameters, the analysis showed a poor correlation between the midfoot, hallux, and the second toe (−0.2 < r < 2); finally the “pressure” analysis showed a poor correlation between FPI, the fourth MTPJ, and the second toe (−0.2 < rs < 0.3) and a moderate correlation between the hallux (r = 0.374) and the fifth MTPJ (r = 0.427). Conclusions. This study emphasizes the constrained correlation between static foot posture observation and dynamic barefoot examination

    The relationship between nesting habitat and hatching success in Caiman latirostris (Crocodylia, Alligatoridae)

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    The Broad-snouted Caiman uses different habitats for nesting; it has temperature-dependent sex determination (TSD) and nesting habitat selection by females could affect sex and other hatchlings characteristics. Here we evaluated reproductive parameters in three nesting habitats: forest, savanna, and floating vegetation. We collected 154 caiman nests during the summer of 2001-2002. Since natural incubation could mask possible clutch-effects, eggs were collected soon after oviposition and artificially incubated. We found that eggs laid in the forest were wider than those laid in savanna, hatching success varied, decreasing from floating vegetation to forest. As egg width is positively correlated to female body size, the present results suggest that female body size could be related to nesting habitat use in Caiman latirostris. However, there were no differences in hatchling size among nesting habitats

    Pd@TiO2/carbon nanohorn electrocatalysts: reversible CO2 hydrogenation to formic acid

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    Direct conversion of carbon dioxide to formic acid at thermodynamic equilibrium is an advantage of enzymatic catalysis, hardly replicated by synthetic analogs, but of high priority for carbon-neutral energy schemes. The bio-mimetic potential of totally inorganic Pd@TiO2 nanoparticles is envisioned herein in combination with Single Walled Carbon NanoHorns (SWCNHs). The high surface nano-carbon entanglement templates a wide distribution of \u201chard-soft\u201d bimetallic sites where the small Pd nanoparticles (1.5 nm) are shielded within the TiO2 phase (Pd@TiO2), while being electrically wired to the electrode by the nanocarbon support. This hybrid electrocatalyst activates CO2 reduction to formic acid at near zero overpotential in the aqueous phase (onset potential at E < 120.05 V vs. RHE, pH = 7.4), while being able to evolve hydrogen via sequential formic acid dehydrogenation. The net result hints at a unique CO2 \u201ccircular catalysis\u201d where formic acid versus H2 selectivity is addressable by flow-reactor technology

    Modulation of N^N′-bidentate chelating pyridyl–pyridylidene amide ligands offers mechanistic insights into Pd-catalysed ethylene/methyl acrylate copolymerisation

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    The efficient copolymerisation of functionalised olefins with alkenes continues to offer considerable challenges to catalyst design. Based on recent work using palladium complexes containing a dissymmetric NN '-bidentate pyridyl-PYA ligand (PYA = pyridylidene amide), which showed a high propensity to insert methyl acrylate, we have here modified this catalyst structure by inserting shielding groups either into the pyridyl fragment, or the PYA unit, or both to avoid fast beta-hydrogen elimination. While a phenyl substituent at the pyridyl side impedes catalytic activity completely and leads to an off-cycle cyclometallation, the introduction of an ortho-methyl group on the PYA side of the NN '-ligand was more prolific and doubled the catalytic productivity. Mechanistic investigations with this ligand system indicated the stabilisation of a 4-membered metallacycle intermediate at room temperature, which has previously been postulated and detected only at 173 K, but never observed at ambient temperature so far. This intermediate was characterised by solution NMR spectroscopy and rationalises, in part, the formation of alpha,beta-unsaturated esters under catalytic conditions, thus providing useful principles for optimised catalyst design
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