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Sökning: WFRF:(Renard N.)

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1.
  • Aamodt, K., et al. (författare)
  • The ALICE experiment at the CERN LHC
  • 2008
  • Ingår i: Journal of Instrumentation. - 1748-0221. ; 3:S08002
  • Forskningsöversikt (refereegranskat)abstract
    • ALICE (A Large Ion Collider Experiment) is a general-purpose, heavy-ion detector at the CERN LHC which focuses on QCD, the strong-interaction sector of the Standard Model. It is designed to address the physics of strongly interacting matter and the quark-gluon plasma at extreme values of energy density and temperature in nucleus-nucleus collisions. Besides running with Pb ions, the physics programme includes collisions with lighter ions, lower energy running and dedicated proton-nucleus runs. ALICE will also take data with proton beams at the top LHC energy to collect reference data for the heavy-ion programme and to address several QCD topics for which ALICE is complementary to the other LHC detectors. The ALICE detector has been built by a collaboration including currently over 1000 physicists and engineers from 105 Institutes in 30 countries, Its overall dimensions are 16 x 16 x 26 m(3) with a total weight of approximately 10 000 t. The experiment consists of 18 different detector systems each with its own specific technology choice and design constraints, driven both by the physics requirements and the experimental conditions expected at LHC. The most stringent design constraint is to cope with the extreme particle multiplicity anticipated in central Pb-Pb collisions. The different subsystems were optimized to provide high-momentum resolution as well as excellent Particle Identification (PID) over a broad range in momentum, up to the highest multiplicities predicted for LHC. This will allow for comprehensive studies of hadrons, electrons, muons, and photons produced in the collision of heavy nuclei. Most detector systems are scheduled to be installed and ready for data taking by mid-2008 when the LHC is scheduled to start operation, with the exception of parts of the Photon Spectrometer (PHOS), Transition Radiation Detector (TRD) and Electro Magnetic Calorimeter (EMCal). These detectors will be completed for the high-luminosity ion run expected in 2010. This paper describes in detail the detector components as installed for the first data taking in the summer of 2008.
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  • Bécoulet, A., et al. (författare)
  • Science and technology research and development in support to ITER and the Broader Approach at CEA
  • 2013
  • Ingår i: Nuclear Fusion. - : IOP Publishing. - 1741-4326 .- 0029-5515. ; 53:10
  • Tidskriftsartikel (refereegranskat)abstract
    • In parallel to the direct contribution to the procurement phase of ITER and Broader Approach, CEA has initiated research & development programmes, accompanied by experiments together with a significant modelling effort, aimed at ensuring robust operation, plasma performance, as well as mitigating the risks of the procurement phase. This overview reports the latest progress in both fusion science and technology including many areas, namely the mitigation of superconducting magnet quenches, disruption-generated runaway electrons, edge-localized modes (ELMs), the development of imaging surveillance, and heating and current drive systems for steady-state operation. The WEST (W Environment for Steady-state Tokamaks) project, turning Tore Supra into an actively cooled W-divertor platform open to the ITER partners and industries, is presented.
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  • Amiri, M., et al. (författare)
  • Periodic activity from a fast radio burst source
  • 2020
  • Ingår i: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 582:7812, s. 351-355
  • Tidskriftsartikel (refereegranskat)abstract
    • Fast radio bursts (FRBs) are bright, millisecond-duration radio transients originating from sources at extragalactic distances1, the origin of which is unknown. Some FRB sources emit repeat bursts, ruling out cataclysmic origins for those events2–4. Despite searches for periodicity in repeat burst arrival times on timescales from milliseconds to many days2,5–7, these bursts have hitherto been observed to appear sporadically and—although clustered8—without a regular pattern. Here we report observations of a 16.35 ± 0.15 day periodicity (or possibly a higher-frequency alias of that periodicity) from the repeating FRB 180916.J0158+65 detected by the Canadian Hydrogen Intensity Mapping Experiment Fast Radio Burst Project4,9. In 38 bursts recorded from 16 September 2018 to 4 February 2020 utc, we find that all bursts arrive in a five-day phase window, and 50 per cent of the bursts arrive in a 0.6-day phase window. Our results suggest a mechanism for periodic modulation either of the burst emission itself or through external amplification or absorption, and disfavour models invoking purely sporadic processes.
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  • Jégou, F., et al. (författare)
  • Validation of Odin/SMR limb observations of ozone, comparisons with OSIRIS, POAM III, ground-based and balloon-borne intruments
  • 2008
  • Ingår i: Atmospheric Chemistry and Physics. - : Copernicus GmbH. - 1680-7316 .- 1680-7324. ; 8:13, s. 3385-3409
  • Tidskriftsartikel (refereegranskat)abstract
    • The Odin satellite carries two instruments capable of determining stratospheric ozone profiles by limb sounding: the Sub-Millimetre Radiometer (SMR) and the UV-visible spectrograph of the OSIRIS (Optical Spectrograph and InfraRed Imager System) instrument. A large number of ozone profiles measurements were performed during six years from November 2001 to present. This ozone dataset is here used to make quantitative comparisons with satellite measurements in order to assess the quality of the Odin/SMR ozone measurements. In a first step, we compare Swedish SMR retrievals version 2.1, French SMR ozone retrievals version 222 (both from the 501.8 GHz band), and the OSIRIS retrievals version 3.0, with the operational version 4.0 ozone product from POAM III (Polar Ozone Atmospheric Measurement). In a second step, we refine the Odin/SMR validation by comparisons with ground-based instruments and balloon-borne observations. We use observations carried out within the framework of the Network for Detection of Atmospheric Composition Change (NDACC) and balloon flight missions conducted by the Canadian Space Agency (CSA), the Laboratoire de Physique et de Chimie de l\'{}Environnement (LPCE, Orléans, France), and the Service d'Aéronomie (SA, Paris, France). Coincidence criteria were 5° in latitude×10° in longitude, and 5 h in time in Odin/POAM III comparisons, 12 h in Odin/NDACC comparisons, and 72 h in Odin/balloons comparisons. An agreement is found with the POAM III experiment (10–60 km) within −0.3±0.2 ppmv (bias±standard deviation) for SMR (v222, v2.1) and within −0.5±0.2 ppmv for OSIRIS (v3.0). Odin ozone mixing ratio products are systematically slightly lower than the POAM III data and show an ozone maximum lower by 1–5 km in altitude. The comparisons with the NDACC data (10–34 km for ozonesonde, 10–50 km for lidar, 10–60 for microwave instruments) yield a good agreement within −0.15±0.3 ppmv for the SMR data and −0.3±0.3 ppmv for the OSIRIS data. Finally the comparisons with instruments on large balloons (10–31 km) show a good agreement, within −0.7±1 ppmv. The official SMR v2.1 dataset is consistent in all altitude ranges with POAM III, NDACC and large balloon-borne instruments measurements. In the SMR v2.1 data, no different systematic error has been found in the 0–35km range in comparison with the 35–60 km range. The same feature has been highlighted in both hemispheres in SMR v2.1/POAM III intercomparisons, and no latitudinal dependence has been revealed in SMR v2.1/NDACC intercomparisons.
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  • Afifi, K., et al. (författare)
  • Features of intracranial hemorrhage in cerebral venous thrombosis
  • 2020
  • Ingår i: Journal of Neurology. - : Springer Science and Business Media LLC. - 0340-5354 .- 1432-1459. ; 267, s. 3292-3298
  • Tidskriftsartikel (refereegranskat)abstract
    • Background Cerebral venous thrombosis (CVT) is associated with intracranial hemorrhage. Aim To identify clinical and imaging features of CVT-associated intracranial hemorrhage. We hypothesized that higher clot burden would be associated with a higher risk of intracranial hemorrhage. Methods We performed a retrospective analysis of an international, multicenter cohort of patients with confirmed cerebral venous thrombosis who underwent computed tomography within 2 weeks of symptom onset. Clinical and imaging features were compared between patients with and without intracranial hemorrhage. Clot burden was assessed by counting the number of thrombosed venous sinuses and veins on confirmatory imaging. Results We enrolled 260 patients from 10 institutions in Europe and Mexico. The mean age was 42 years and 74% were female. Intracranial hemorrhage was found in 102 (39%). Among them parenchymal hemorrhage occurred in 64 (63%), in addition, small juxta-cortical hemorrhage was found in 30 (29%), subarachnoid hemorrhage in 24 (24%) and subdural hemorrhage in 11 (11%). Multiple concomitant types of hemorrhage occurred in 23 (23%). Older age and superior sagittal thrombosis involvement were associated with presence of hemorrhage. The number of thrombosed venous sinuses was not associated with intracranial hemorrhage (median number IQRInterquartile ratio] of sinuses/veins involved with hemorrhage 2 (1-3) vs. 2 (1-3) without hemorrhage,p = 0.4). Conclusion The high rate of intracranial hemorrhage in cerebral venous thrombosis is not explained by widespread involvement of the venous sinuses. Superior sagittal sinus involvement is associated with higher bleeding risk.
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  • Buyck, P. J., et al. (författare)
  • Diagnostic accuracy of noncontrast CT imaging markers in cerebral venous thrombosis
  • 2019
  • Ingår i: Neurology. - : Ovid Technologies (Wolters Kluwer Health). - 0028-3878 .- 1526-632X. ; 92:8
  • Tidskriftsartikel (refereegranskat)abstract
    • Objective To assess the added diagnostic value of semiquantitative imaging markers on noncontrast CT scans in cerebral venous thrombosis (CVT). Methods In a retrospective, multicenter, blinded, case-control study of patients with recent onset (<2 weeks) CVT, 3 readers assessed (1) the accuracy of the visual impression of CVT based on a combination of direct and indirect signs, (2) the accuracy of attenuation values of the venous sinuses in Hounsfield units (with adjustment for hematocrit levels), and (3) the accuracy of attenuation ratios of affected vs unaffected sinuses in comparison with reference standard MRI or CT angiography. Controls were age-matched patients with (sub)acute neurologic presentations. Results We enrolled 285 patients with CVT and 303 controls from 10 international centers. Sensitivity of visual impression of thrombosis ranged from 41% to 73% and specificity ranged from 97% to 100%. Attenuation measurement had an area under the curve (AUC) of 0.78 (95% confidence interval [CI] 0.74-0.81). After adjustment for hematocrit, the AUC remained 0.78 (95% CI 0.74-0.81). The analysis of attenuation ratios of affected vs unaffected sinuses had AUC of 0.83 (95% CI 0.8-0.86). Adding this imaging marker significantly improved discrimination, but sensitivity when tolerating a false-positive rate of 20% was not higher than 76% (95% CI 0.70-0.81). Conclusion Semiquantitative analysis of attenuation values for diagnosis of CVT increased sensitivity but still failed to identify 1 out of 4 CVT. Classification of evidence This study provides Class II evidence that visual analysis of plain CT with or without attenuation measurements has high specificity but only moderate sensitivity for CVT.
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  • Fernandes-Cerqueira, C, et al. (författare)
  • Patients with anti-Jo1 antibodies display a characteristic IgG Fc-glycan profile which is further enhanced in anti-Jo1 autoantibodies
  • 2018
  • Ingår i: Scientific reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 8:1, s. 17958-
  • Tidskriftsartikel (refereegranskat)abstract
    • IgG Fc-glycans affect IgG function and are altered in autoimmune diseases and autoantibodies. Anti-histidyl tRNA synthetase autoantibodies (anti-Jo1) are frequent in patients with idiopathic inflammatory myopathies (IIM) and anti-synthetase syndrome (ASS) with associated interstitial lung disease (ILD). Thus, we hypothesized that the total-IgG Fc-glycans from Jo1+ versus Jo1− patients and anti-Jo1-IgG would show characteristic differences, and that particular Fc-glycan features would be associated with specific clinical manifestations. By proteomics based mass spectrometry we observed a high abundance of agalactosylated IgG1 Fc-glycans in ASS/IIM patients (n = 44) compared to healthy age matched controls (n = 24). Using intra-individual normalization of the main agalactosylated glycan (FA2) of IgG1 vs FA2-IgG2, ASS/IIM and controls were distinguished with an area under the curve (AUC) of 79 ± 6%. For Jo1+ patients (n = 19) the AUCs went up to 88 ± 6%. Bisected and afucosylated Fc-glycans were significantly lower in Jo1+ compared to Jo1− patients. Anti-Jo1-IgG enriched from eleven patients contained even significantly lower abundances of bisected, afucosylated and galactosylated forms compared to matched total-IgG. ASS and ILD diagnosis, as well as lysozyme and thrombospondin correlated with Jo1+ characteristic Fc-glycan features. These results suggest that the anti-Jo1+ patient Fc-glycan profile contains phenotype specific features which may underlie the pathogenic role of Jo1 autoantibodies.
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  • Henriksen, N. A., et al. (författare)
  • EHS and AHS guidelines for treatment of primary ventral hernias in rare locations or special circumstances
  • 2020
  • Ingår i: BJS Open. - : Oxford University Press (OUP). - 2474-9842. ; 4:2, s. 342-353
  • Forskningsöversikt (refereegranskat)abstract
    • BACKGROUND: Rare locations of hernias, as well as primary ventral hernias under certain circumstances (cirrhosis, dialysis, rectus diastasis, subsequent pregnancy), might be technically challenging. The aim was to identify situations where the treatment strategy might deviate from routine management. METHODS: The guideline group consisted of surgeons from the European and Americas Hernia Societies. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach was used in formulating the recommendations. The Scottish Intercollegiate Guidelines Network (SIGN) critical appraisal checklists were used to evaluate the quality of full-text papers. A systematic literature search was performed on 1 May 2018 and updated 1 February 2019. The Appraisal of Guidelines for Research and Evaluation (AGREE) instrument was followed. RESULTS: Literature was limited in quantity and quality. A majority of the recommendations were graded as weak, based on low quality of evidence. In patients with cirrhosis or on dialysis, a preperitoneal mesh repair is suggested. Subsequent pregnancy is a risk factor for recurrence. Repair should be postponed until after the last pregnancy. For patients with a concomitant rectus diastasis or those with a Spigelian or lumbar hernia, no recommendation could be made for treatment strategy owing to lack of evidence. CONCLUSION: This is the first European and American guideline on the treatment of umbilical and epigastric hernias in patients with special conditions, including Spigelian and lumbar hernias. All recommendations were weak owing to a lack of evidence. Further studies are needed on patients with rectus diastasis, Spigelian and lumbar hernias.
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  • Henriksen, N. A., et al. (författare)
  • Guidelines for treatment of umbilical and epigastric hernias from the European Hernia Society and Americas Hernia Society
  • 2020
  • Ingår i: British Journal of Surgery. - : Oxford University Press (OUP). - 0007-1323 .- 1365-2168. ; 107:3, s. 171-190
  • Forskningsöversikt (refereegranskat)abstract
    • Background: Umbilical and epigastric hernia repairs are frequently performed surgical procedures with an expected low complication rate. Nevertheless, the optimal method of repair with best short- and long-term outcomes remains debatable. The aim was to develop guidelines for the treatment of umbilical and epigastric hernias. Methods: The guideline group consisted of surgeons from Europe and North America including members from the European Hernia Society and the Americas Hernia Society. The Grading of Recommendations, Assessment, Development and Evaluation (GRADE) approach, the Scottish Intercollegiate Guidelines Network (SIGN) critical appraisal checklists, and the Appraisal of Guidelines for Research and Evaluation (AGREE) instrument were used. A systematic literature search was done on 1 May 2018, and updated on 1 February 2019. Results: Literature reporting specifically on umbilical and epigastric hernias was limited in quantity and quality, resulting in a majority of the recommendations being graded as weak, based on low-quality evidence. The main recommendation was to use mesh for repair of umbilical and epigastric hernias to reduce the recurrence rate. Most umbilical and epigastric hernias may be repaired by an open approach with a preperitoneal flat mesh. A laparoscopic approach may be considered if the hernia defect is large, or if the patient has an increased risk of wound morbidity. Conclusion: This is the first European and American guideline on the treatment of umbilical and epigastric hernias. It is recommended that symptomatic umbilical and epigastric hernias are repaired by an open approach with a preperitoneal flat mesh.
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  • Notarnicola, A., et al. (författare)
  • Serum and balf-derived anti-JO1 autoantibodies exhibit high reactivity to distinct HISRS domains and associate with lung and joint involvement in patients with IIM/ASS
  • 2020
  • Ingår i: Annals of the Rheumatic Diseases. - : BMJ Publishing Group. - 0003-4967 .- 1468-2060. ; 79, s. 1109-1110
  • Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
    • Autoantibodies that target aminoacyl transfer(t) RNA synthetases (aaRS) represent the serological marker of the anti-synthetase syndrome (ASS), a major subgroup of the idiopathic inflammatory myopathies (IIM) (1). Among the anti-aaRS, anti-histidyl tRNA synthetase (HisRS) autoantibodies (anti-Jo1) are the most common. Up to 90% of IIM/ASS patients diagnosed with interstitial lung disease (ILD) harbor anti-Jo1 autoantibodies (2).Objectives:Reactivity and affinity of anti-Jo1 autoantibodies from serum and broncheoalveolar lavage fluid (BALF) were investigated against HisRS autoantigen. Associations with clinical data from patients IIM/ASS were addressed.Methods:Total IgGs were purified by affinity chromatography. Samples and clinical data were obtained from: i) 26 anti-Jo1+patients (19 at diagnosis, 16/19 at follow-up, 7 BALF/matching serum at baseline; ii) 29 anti-Jo1-(25 serum at diagnosis, 4 BALF/matching serum at baseline); iii) 24 age/gender matched healthy controls. Anti-Jo1 IgG and IgA response against HisRS was evaluated by ELISA and western blot. Affinity was measured by surface plasmon resonance. HisRS full-length (HisRS-FL), two HisRS domains (ABD and CD), and two HisRS splice variants (WHEP and WHEP + ABD splice variant (SV)) were tested. Correlations between autoantibody reactivity and clinical data, at baseline and over disease course, were evaluated.Results:Anti-Jo1 autoantibodies from serum and lung bound HisRS-FL, WHEP and SV with high reactivity and affinity already at diagnosis and recognized both conformational and linear HisRS epitopes (Fig. 1). Levels of autoantibodies (against HisRS-FL, -domains and -splice variants) varied among patients and overtime. Patients with ILD, arthritis and less skin involvement presented higher anti-Jo1 titers compared to those with lower anti-Jo1 titers and to the anti-Jo1 negative group (Fig. 2). Anti-WHEP reactivity in BALF strongly correlated with poor pulmonary function.Conclusion:High reactivity and affinity at time of diagnosis indicates that autoimmunity against HisRS is most likely initiated before IIM/ASS diagnosis. Reactivity to specific splice variants of HisRS may be employed as diagnostic and prognostic markers.References:[1]Marguerie C, Bunn CC, Beynon HL, Bernstein RM, Hughes JM, So AK, Walport MJ: Polymyositis, pulmonary fibrosis and autoantibodies to aminoacyl-tRNA synthetase enzymes. Q J Med 1990, 77(282):1019-1038[2]Richards TJ, Eggebeen A, Gibson K, Yousem S, Fuhrman C, Gochuico BR, Fertig N, Oddis CV, Kaminski N, Rosas IO et al: Characterization and peripheral blood biomarker assessment of anti-Jo-1 antibody-positive interstitial lung disease. Arthritis Rheum 2009, 60(7):2183-2192.Fig. 1.Anti-Jo1 reactivity in total IgG purified from the first available serum sampleFig. 2.Reactivity of total anti-Jo1+ IgG purified from the first available serum close to IIM/ASS diagnosis in relation to clinical dataDisclosure of Interests:Antonella Notarnicola: None declared, Charlotta Preger: None declared, Susanna Lundström: None declared, Nuria Renard: None declared, Edvard Wigren: None declared, Eveline Van Gompel: None declared, Angeles Shunashy Galindo-Feria: None declared, Helena Persson: None declared, Maryam Fathi: None declared, Johan Grunewald: None declared, Per-Johan Jakobsson Shareholder of: Gesynta Pharma, Grant/research support from: Gesynta Pharma, AstraZeneca,, Susanne Gräslund: None declared, Ingrid E. Lundberg Grant/research support from: Bristol Meyer Squibb, Corbus Pharmaceuticals, Inc and Astra Zeneca, Catia Cerqueira: None declared
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  • Renard, M, et al. (författare)
  • Expressed repetitive elements are broadly applicable reference targets for normalization of reverse transcription-qPCR data in mice
  • 2018
  • Ingår i: Scientific reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 8:1, s. 7642-
  • Tidskriftsartikel (refereegranskat)abstract
    • Reverse transcription quantitative PCR (RT-qPCR) is the gold standard method for gene expression analysis on mRNA level. To remove experimental variation, expression levels of the gene of interest are typically normalized to the expression level of stably expressed endogenous reference genes. Identifying suitable reference genes and determining the optimal number of reference genes should precede each quantification study. Popular reference genes are not necessarily stably expressed in the examined conditions, possibly leading to inaccurate results. Stably and universally expressed repetitive elements (ERE) have previously been shown to be an excellent alternative for normalization using classic reference genes in human and zebrafish samples. Here, we confirm that in mouse tissues, EREs are broadly applicable reference targets for RT-qPCR normalization, provided that the RNA samples undergo a thorough DNase treatment. We identified Orr1a0, Rltr2aiap, and Rltr13a3 as the most stably expressed mouse EREs across six different experimental conditions. Therefore, we propose this set of ERE reference targets as good candidates for normalization of RT-qPCR data in a plethora of conditions. The identification of widely applicable stable mouse RT-qPCR reference targets for normalization has great potential to facilitate future murine gene expression studies and improve the validity of RT-qPCR data.
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  • Vignelles, D., et al. (författare)
  • Balloon-borne measurement of the aerosol size distribution from an Icelandic flood basalt eruption
  • 2016
  • Ingår i: Earth and Planetary Science Letters. - : Elsevier BV. - 1385-013X .- 0012-821X. ; 453, s. 252-259
  • Tidskriftsartikel (refereegranskat)abstract
    • We present in situ balloon-borne measurements of aerosols in a volcanic plume made during the Holuhraun eruption (Iceland) in January 2015. The balloon flight intercepted a young plume at 8 km distance downwind from the crater, where the plume is 15 min of age. The balloon carried a novel miniature optical particle counter LOAC (Light Optical Aerosol Counter) which measures particle number concentration and size distribution in the plume, alongside a meteorological payload. We discuss the possibility of calculating particle flux by combining LOAC data with measurements of sulfur dioxide flux by ground-based UV spectrometer (DOAS). The balloon passed through the plume at altitude range of 2.0-3.1 km above sea level (a.s.l.). The plume top height was determined as 2.7-3.1 km a.s.l., which is in good agreement with data from Infrared Atmospheric Sounding Interferometer (IASI) satellite. Two distinct plume layers were detected, a non condensed lower layer (300 m thickness) and a condensed upper layer (800 m thickness). The lower layer was characterized by a lognormal size distribution of fine particles (0.2 mu m diameter) and a secondary, coarser mode (2.3 mu m diameter), with a total particle number concentration of around 100 cm(-3) in the 0.2-100 mu m detection range. The upper layer was dominated by particle centered on 20 mu m in diameter as well as containing a finer mode (2 mu m diameter). The total particle number concentration in the upper plume layer was an order of magnitude higher than in the lower layer. We demonstrate that intercepting a volcanic plume with a meteorological balloon carrying LOAC is an efficient method to characterize volcanic aerosol properties. During future volcanic eruptions, balloon borne measurements could be carried out easily and rapidly over a large spatial area in order to better characterize the evolution of the particle size distribution and particle number concentrations in a volcanic plume.
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