In this review, the Basic and Translational Sciences Assembly of the European Respiratory Society (ERS) provides an overview of the 2019 ERS International Congress highlights. In particular, we... Show moreIn this review, the Basic and Translational Sciences Assembly of the European Respiratory Society (ERS) provides an overview of the 2019 ERS International Congress highlights. In particular, we discuss how the novel and very promising technology of single cell sequencing has led to the development of a comprehensive map of the human lung, the lung cell atlas, including the discovery of novel cell types and new insights into cellular trajectories in lung health and disease. Further, we summarise recent insights in the field of respiratory infections, which can aid in a better understanding of the molecular mechanisms underlying these infections in order to develop novel vaccines and improved treatment options. Novel concepts delineating the early origins of lung disease are focused on the effects of pre- and post-natal exposures on neonatal lung development and long-term lung health. Moreover, we discuss how these early life exposures can affect the lung microbiome and respiratory infections. In addition, the importance of metabolomics and mitochondrial function analysis to subphenotype chronic lung disease patients according to their metabolic program is described. Finally, basic and translational respiratory science is rapidly moving forward and this will be beneficial for an advanced molecular understanding of the mechanisms underlying a variety of lung diseases. In the long-term this will aid in the development of novel therapeutic targeting strategies in the field of respiratory medicine. Show less
Charbit-Henrion, F.; Parlato, M.; Hanein, S.; Duclaux-Loras, R.; Nowak, J.; Begue, B.; ... ; Cerf-Bensussan, N. 2018
The article by Andrea Fabre et al. (Environ. Sci.: Nano, 2017, 4, 670–678) was published with an incorrect title (‘Modeling thesize distribution in a fluidized bed of nanopowder’). The correct... Show moreThe article by Andrea Fabre et al. (Environ. Sci.: Nano, 2017, 4, 670–678) was published with an incorrect title (‘Modeling thesize distribution in a fluidized bed of nanopowder’). The correct article title is ‘Entrainment of nanosized clusters from a nanopowder fluidized bed’. Show less
The release of nanosized particles from fluidized beds of ceramic oxide nanopowders, namely, TiO2 (P25), Al2O3 (AluC) and SiO2 (A130) has been assessed for the first time. Previous models and... Show moreThe release of nanosized particles from fluidized beds of ceramic oxide nanopowders, namely, TiO2 (P25), Al2O3 (AluC) and SiO2 (A130) has been assessed for the first time. Previous models and experiments for processing engineered nanoparticles (ENP) using fluidized beds reported only the formation of micron-sized cluster agglomerates in the gas phase. In this work, aerosol spectrometry techniques such as scanning mobility particle sizing (SMPS) and optical particle counting (OPC) have been combined with powder technologies, such as the borescope high-speed camera system, to determine the particle size distribution from 5 nm to 1 mm above a fluidized bed. Furthermore, the morphology of nanoparticulate aerosol at different locations in the bed was determined by offline electron microscopy. The results demonstrate that free nano- and micron-sized particles are released from fluidized beds. Since the structures found above the bed are also expected to be present within fluidized beds, a revision of existing nanoparticle fluidization models, and improved safety and control measures in reactors for gas-phase ENP processing are needed to avoid nanoparticle release. Show less
Fabre, A.; Salameh, S.; Kreutzer, M.T.; Ommen, J.R. van 2017
Fluidization is a technique used to process large quantities of nanopowder with no solvent waste and a large gas-solid contact area. Nonetheless, nanoparticles in the gas phase form clusters,... Show moreFluidization is a technique used to process large quantities of nanopowder with no solvent waste and a large gas-solid contact area. Nonetheless, nanoparticles in the gas phase form clusters, called agglomerates, due to the relatively large adhesion forces. The dynamics within the fluidized bed influence the mechanism of formation, and thus, the morphology of the agglomerates. There are many theoretical models to predict the average size of fluidized agglomerates; however, these estimates of the average lack information on the whole size range. Here, we predict the agglomerate size distribution within the fluidized bed by estimating the mode and width using a force balance model. The model was tested for titania (TiO2), alumina (Al2O3), and silica (SiO2) nanopowders, which were studied experimentally. An in-situ method was used to record the fluidized agglomerates for size analysis and model validation. (C) 2017 Elsevier B.V. All rights reserved. Show less
Nanoparticles surrounded by gas agglomerate in a hierarchical fashion. From production until powder processing in the gas phase, nanoparticles go from individual particles to aggregates, simple... Show moreNanoparticles surrounded by gas agglomerate in a hierarchical fashion. From production until powder processing in the gas phase, nanoparticles go from individual particles to aggregates, simple agglomerates, and complex agglomerates. Even though the structures at each level have unique properties, they are commonly assessed as a whole. Additionally, the effect of external factors on the morphology of these structures during gas processing is not well understood and challenging to study due to the limited techniques for in situ analysis of the dynamic phenomenon. Here, we study three materials in their hydrophobic and hydrophilic version. We describe the structural characteristics of each hierarchical level of complex agglomerate formation obtained from two in situ techniques. The first scale, namely aggregates, are open structures with a fractal dimension of about 1.5, which then form simple agglomerates with a fractal dimension close to 3, that later cluster into complex agglomerates that present a fractal dimension of about 2. Furthermore, gas dynamics were found to densify the simple agglomerates, increasing their fractal dimension by more than 0.1. Show less
Efficient nanopowder processing requires knowledge of the powder's mechanical properties. Due to the large surface area to volume ratio, nanoparticles experience relatively strong attractive... Show moreEfficient nanopowder processing requires knowledge of the powder's mechanical properties. Due to the large surface area to volume ratio, nanoparticles experience relatively strong attractive interactions, leading to the formation of micron-size porous structures called agglomerates. Significant effort has been directed towards the development of models and experimental procedures to estimate the elasticity of porous objects such as nanoparticle agglomerates; however, none of the existing models has been validated for solid fractions below 0.1. Here, we measure the elasticity of titania (TiO, 22 nm), alumina (AlO, 8 nm), and silica (SiO, 16 nm) nanopowder agglomerates by Atomic Force Microscopy, using a 3.75 m glass colloid for the stress-strain experiments. Three sample preparations with varying degree of powder manipulation are assessed. The measured Young's moduli are in the same order of magnitude as those predicted by the model of Kendall et al., thus validating it for the estimation of the Young's modulus of structures with porosity above 90 %. Show less
