175 research outputs found

    Hereditary pancreatitis in children: surgical implications with special regard to genetic background.

    Get PDF
    PURPOSE: Hereditary pancreatitis (HP) is the primary etiology of chronic pancreatitis during childhood, progressing through recurrent episodes of acute pancreatitis and finally leading to pancreatic insufficiencies. Hereditary pancreatitis is because of mutations of the cationic trypsinogen (PRSS1) gene. Some other genes, such as SPINK1 or CFTR, have been associated with familial idiopathic chronic pancreatitis. The aim of our study was to clearly define diagnostic and therapeutic strategies for HP patients, through an analysis of our study group and a review of the literature. METHODS: All children admitted from 1995 to 2007 with a final diagnosis of hereditary pancreatitis were restrospectively included in the study. We analyzed all medical records with special attention given to cases involving genetic screening (PRSS1, SPINK1, and CFTR genes). RESULTS: Ten children were included. Eight had HP with PRSS1 mutation, 2 of them without a familial history of chronic pancreatitis. The 2 others patients had SPINK1 mutations. Three HP patients were operated on for acute complications of pancreatitis and are well with a mean follow-up of 5.5 years. No patient had pancreatic insufficiencies or weight loss. CONCLUSIONS: Hereditary pancreatitis is associated with severe pancreatitis, with a greater risk of developing pancreatic cancer. It must therefore be diagnosed correctly and treated to prevent its considerable complications

    ARPEGES, une méthode pour évaluer le potentiel de contamination des eaux de surface par les pesticides à l'échelle nationale

    Get PDF
    International audienceArpeges is an innovating and coherent method to assess the potential surface water's contamination by pesticides at the national scale. In France, it was implemented at Water Framework Directive water bodies' scale. The objectives are to identify of vulnerable zones and to determinate the main risk factors implied in pollution transfer according to the considered zones. Actually, this method allows a better understanding and a ranking of pollution's causes considering three essential aspects of the contamination: uses, environmental vulnerability to pesticides pollution and substances properties. The method is mostly based on transfer processes. In order to take into account the seasonal temporal variability, analyses are separately carried on winter and summer, and both acute and chronic approaches of the risk are considered. The segregation between these two risks is built on the different processes transfer times to reach surface waters. 18 relevant variables describing pesticides transfer are chosen (infiltration, pedology, drainage, climate, buffer zones...); they are aggregated according to up to date expert knowledge thanks to a Bayesian network to obtain pesticides contamination. This tool allows associating an uncertainty factor to each result and contributing to increase the adaptability of the method. Intermediary results as environmental vulnerabilities are relevant to identify the main causes of transfer

    Voltage- and flow-controlled electrodialysis batch operation : flexible and optimized brackish water desalination

    Get PDF
    Electrodialysis (ED) desalination has been demonstrated to be more energy-efficient, provide higher-recovery, and be lower-cost for producing drinking water from saline groundwater compared to reverse osmosis. These benefits of ED could translate into cost-effective, renewable-powered desalination solutions. However, the challenge of using a variable power source (e.g. solar) with traditional steady-state ED operation requires batteries to reshape the power source to match the desalination load; these batteries often contribute to a large fraction of the produced water cost. In this study, we propose a time-variant voltage- and flow-controlled ED operation that can enable highly flexible desalination from variable power sources, including renewables, with negligible batteries, potentially leading to reduced water costs compared to what existing technology can provide. A model-based controller is presented which varies applied ED stack voltage and pumping flow rate to match power consumption to a variable source while maximizing desalination rate throughout an ED batch. The utility of the controller was demonstrated with a pilot-scale system tested with brackish groundwater, which operated as expected under varying fixed power levels and a real solar irradiance profile. The pilot system achieved a production rate up to 45% higher than that of an equivalently sized traditional steady-state ED system

    SoLid: A short baseline reactor neutrino experiment

    Get PDF
    The SoLid experiment, short for Search for Oscillations with a Lithium-6 detector, is a new generation neutrino experiment which tries to address the key challenges for high precision reactor neutrino measurements at very short distances from a reactor core and with little or no overburden. The primary goal of the SoLid experiment is to perform a precise measurement of the electron antineutrino energy spectrum and flux and to search for very short distance neutrino oscillations as a probe of eV-scale sterile neutrinos. This paper describes the SoLid detection principle, the mechanical design and the construction of the detector. It then reports on the installation and commissioning on site near the BR2 reactor, Belgium, and finally highlights its performance in terms of detector response and calibration

    Commissioning and operation of the readout system for the solid neutrino detector

    Get PDF
    The SoLid experiment aims to measure neutrino oscillation at a baseline of 6.4 m from the BR2 nuclear reactor in Belgium. Anti-neutrinos interact via inverse beta decay (IBD), resulting in a positron and neutron signal that are correlated in time and space. The detector operates in a surface building, with modest shielding, and relies on extremely efficient online rejection of backgrounds in order to identify these interactions. A novel detector design has been developed using 12800 5 cm cubes for high segmentation. Each cube is formed of a sandwich of two scintillators, PVT and 6LiF:ZnS(Ag), allowing the detection and identification of positrons and neutrons respectively. The active volume of the detector is an array of cubes measuring 80x80x250 cm (corresponding to a fiducial mass of 1.6 T), which is read out in layers using two dimensional arrays of wavelength shifting fibres and silicon photomultipliers, for a total of 3200 readout channels. Signals are recorded with 14 bit resolution, and at 40 MHz sampling frequency, for a total raw data rate of over 2 Tbit/s. In this paper, we describe a novel readout and trigger system built for the experiment, that satisfies requirements on: compactness, low power, high performance, and very low cost per channel. The system uses a combination of high price-performance FPGAs with a gigabit Ethernet based readout system, and its total power consumption is under 1 kW. The use of zero suppression techniques, combined with pulse shape discrimination trigger algorithms to detect neutrons, results in an online data reduction factor of around 10000. The neutron trigger is combined with a large per-channel history time buffer, allowing for unbiased positron detection. The system was commissioned in late 2017, with successful physics data taking established in early 2018

    The Cell Adhesion Molecule “CAR” and Sialic Acid on Human Erythrocytes Influence Adenovirus In Vivo Biodistribution

    Get PDF
    Although it has been known for 50 years that adenoviruses (Ads) interact with erythrocytes ex vivo, the molecular and structural basis for this interaction, which has been serendipitously exploited for diagnostic tests, is unknown. In this study, we characterized the interaction between erythrocytes and unrelated Ad serotypes, human 5 (HAd5) and 37 (HAd37), and canine 2 (CAV-2). While these serotypes agglutinate human erythrocytes, they use different receptors, have different tropisms and/or infect different species. Using molecular, biochemical, structural and transgenic animal-based analyses, we found that the primary erythrocyte interaction domain for HAd37 is its sialic acid binding site, while CAV-2 binding depends on at least three factors: electrostatic interactions, sialic acid binding and, unexpectedly, binding to the coxsackievirus and adenovirus receptor (CAR) on human erythrocytes. We show that the presence of CAR on erythrocytes leads to prolonged in vivo blood half-life and significantly reduced liver infection when a CAR-tropic Ad is injected intravenously. This study provides i) a molecular and structural rationale for Ad–erythrocyte interactions, ii) a basis to improve vector-mediated gene transfer and iii) a mechanism that may explain the biodistribution and pathogenic inconsistencies found between human and animal models

    Analysis of test beam data taken with a prototype of TPC with resistive Micromegas for the T2K Near Detector upgrade

    Full text link
    In this paper we describe the performance of a prototype of the High Angle Time Projection Chambers (HA-TPCs) that are being produced for the Near Detector (ND280) upgrade of the T2K experiment. The two HA-TPCs of ND280 will be instrumented with eight Encapsulated Resistive Anode Micromegas (ERAM) on each endplate, thus constituting in total 32 ERAMs. This innovative technique allows the detection of the charge emitted by ionization electrons over several pads, improving the determination of the track position. The TPC prototype has been equipped with the first ERAM module produced for T2K and with the HA-TPC readout electronics chain and it has been exposed to the DESY Test Beam in order to measure spatial and dE/dx resolution. In this paper we characterize the performances of the ERAM and, for the first time, we compare them with a newly developed simulation of the detector response. Spatial resolution better than 800 μm{\mu \rm m} and dE/dx resolution better than 10% are observed for all the incident angles and for all the drift distances of interest. All the main features of the data are correctly reproduced by the simulation and these performances fully fulfill the requirements for the HA-TPCs of T2K

    Measurements of the νμ\nu_{\mu} and νˉμ\bar{\nu}_{\mu}-induced Coherent Charged Pion Production Cross Sections on 12C^{12}C by the T2K experiment

    Get PDF
    We report an updated measurement of the νμ\nu_{\mu}-induced, and the first measurement of the νˉμ\bar{\nu}_{\mu}-induced coherent charged pion production cross section on 12C^{12}C nuclei in the T2K experiment. This is measured in a restricted region of the final-state phase space for which pμ,π>0.2p_{\mu,\pi} > 0.2 GeV, cos(θμ)>0.8\cos(\theta_{\mu}) > 0.8 and cos(θπ)>0.6\cos(\theta_{\pi}) > 0.6, and at a mean (anti)neutrino energy of 0.85 GeV using the T2K near detector. The measured νμ\nu_{\mu} CC coherent pion production flux-averaged cross section on 12C^{12}C is (2.98±0.37(stat.)±0.31(syst.)+0.490.00(Q2model))×1040 cm2(2.98 \pm 0.37 (stat.) \pm 0.31 (syst.) \substack{ +0.49 \\ -0.00 } \mathrm{ (Q^2\,model)}) \times 10^{-40}~\mathrm{cm}^{2}. The new measurement of the νˉμ\bar{\nu}_{\mu}-induced cross section on 12C^{12}{C} is (3.05±0.71(stat.)±0.39(syst.)+0.740.00(Q2model))×1040 cm2(3.05 \pm 0.71 (stat.) \pm 0.39 (syst.) \substack{ +0.74 \\ -0.00 } \mathrm{(Q^2\,model)}) \times 10^{-40}~\mathrm{cm}^{2}. The results are compatible with both the NEUT 5.4.0 Berger-Sehgal (2009) and GENIE 2.8.0 Rein-Sehgal (2007) model predictions
    corecore