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- ItemSize, concentration, and origin of human exhaled particles and their dependence on human factors with implications on infection transmission(Amsterdam [u.a.] : Elsevier, 2022) Bagheri, Gholamhossein; Schlenczek, Oliver; Turco, Laura; Thiede, Birte; Stieger, Katja; Kosub, Jana M.; Clauberg, Sigrid; Pöhlker, Mira L.; Pöhlker, Christopher; Moláček, Jan; Scheithauer, Simone; Bodenschatz, EberhardUnderstanding infection transmission between individuals, as well as evaluating the efficacy of protective measures, are key issues in pandemics driven by human respiratory particles. The key is a quantitative understanding of the size and concentration of particles exhaled and their variability across the size range for a representative population of all ages, genders, and different activities. Here we present data from 132 healthy volunteers aged 5 to 80 years, measured over the entire particle size range for each individual. Conventional particle spectrometry was combined with in-line holography under well-controlled conditions for common activities such as breathing, speaking, singing, and shouting. We find age to be the most important parameter for the concentration of small exhale particles <5 µm (PM5), which doubles over a 7-year period in adolescents and over a 30-year period in adults. Gender, body mass index, smoking or exercise habits have no discernible effect. We provide evidence that particles with a diameter of <5 µm originate from the lower respiratory tract, 5–15 µm from the larynx/pharynx, and >15 µm from the oral cavity. PM5 concentration can vary by one order of magnitude within a person, while inter-person variability can span two orders of magnitude, largely explained by difference in age. We found no discernible inter-person variability for particles larger than 5 µm. Our results show that cumulative volume of PM5 is 2–8 times higher in adults than in children. In contrast, number and volume concentration of larger particles, which are produced predominantly in the upper respiratory tract, is largely independent of age. Finally, we examined different types of airborne-transmissible respiratory diseases and provided insights into possible modes of infection transmission with and without several types/fits of face masks.
- ItemEUREC4A(Katlenburg-Lindau : Copernics Publications, 2021) Stevens, Bjorn; Bony, Sandrine; Farrell, David; Ament, Felix; Blyth, Alan; Fairall, Christopher; Karstensen, Johannes; Quinn, Patricia K.; Speich, Sabrina; Acquistapace, Claudia; Aemisegger, Franziska; Crewell, Susanne; Cronin, Timothy; Cui, Zhiqiang; Cuypers, Yannis; Daley, Alton; Damerell, Gillian M.; Dauhut, Thibaut; Deneke, Hartwig; Desbios, Jean-Philippe; Dörner, Steffen; Albright, Anna Lea; Donner, Sebastian; Douet, Vincent; Drushka, Kyla; Dütsch, Marina; Ehrlich, André; Emanuel, Kerry; Emmanouilidis, Alexandros; Etienne, Jean-Claude; Etienne-Leblanc, Sheryl; Faure, Ghislain; Bellenger, Hugo; Feingold, Graham; Ferrero, Luca; Fix, Andreas; Flamant, Cyrille; Flatau, Piotr Jacek; Foltz, Gregory R.; Forster, Linda; Furtuna, Iulian; Gadian, Alan; Galewsky, Joseph; Bodenschatz, Eberhard; Gallagher, Martin; Gallimore, Peter; Gaston, Cassandra; Gentemann, Chelle; Geyskens, Nicolas; Giez, Andreas; Gollop, John; Gouirand, Isabelle; Gourbeyre, Christophe; de Graaf, Dörte; Caesar, Kathy-Ann; de Groot, Geiske E.; Grosz, Robert; Güttler, Johannes; Gutleben, Manuel; Hall, Kashawn; Harris, George; Helfer, Kevin C.; Henze, Dean; Herbert, Calvert; Holanda, Bruna; Chewitt-Lucas, Rebecca; Ibanez-Landeta, Antonio; Intrieri, Janet; Iyer, Suneil; Julien, Fabrice; Kalesse, Heike; Kazil, Jan; Kellman, Alexander; Kidane, Abiel T.; Kirchner, Ulrike; Klingebiel, Marcus; de Boer, Gijs; Körner, Mareike; Kremper, Leslie Ann; Kretzschmar, Jan; Krüger, Ovid; Kumala, Wojciech; Kurz, Armin; L'Hégaret, Pierre; Labaste, Matthieu; Lachlan-Cope, Tom; Laing, Arlene; Delanoë, Julien; Landschützer, Peter; Lang, Theresa; Lange, Diego; Lange, Ingo; Laplace, Clément; Lavik, Gauke; Laxenaire, Rémi; Le Bihan, Caroline; Leandro, Mason; Lefevre, Nathalie; Denby, Leif; Lena, Marius; Lenschow, Donald; Li, Qiang; Lloyd, Gary; Los, Sebastian; Losi, Niccolò; Lovell, Oscar; Luneau, Christopher; Makuch, Przemyslaw; Malinowski, Szymon; Ewald, Florian; Manta, Gaston; Marinou, Eleni; Marsden, Nicholas; Masson, Sebastien; Maury, Nicolas; Mayer, Bernhard; Mayers-Als, Margarette; Mazel, Christophe; McGeary, Wayne; McWilliams, James C.; Fildier, Benjamin; Mech, Mario; Mehlmann, Melina; Meroni, Agostino Niyonkuru; Mieslinger, Theresa; Minikin, Andreas; Minnett, Peter; Möller, Gregor; Morfa Avalos, Yanmichel; Muller, Caroline; Musat, Ionela; Forde, Marvin; Napoli, Anna; Neuberger, Almuth; Noisel, Christophe; Noone, David; Nordsiek, Freja; Nowak, Jakub L.; Oswald, Lothar; Parker, Douglas J.; Peck, Carolyn; Person, Renaud; George, Geet; Philippi, Miriam; Plueddemann, Albert; Pöhlker, Christopher; Pörtge, Veronika; Pöschl, Ulrich; Pologne, Lawrence; Posyniak, Michał; Prange, Marc; Quiñones Meléndez, Estefanía; Radtke, Jule; Gross, Silke; Ramage, Karim; Reimann, Jens; Renault, Lionel; Reus, Klaus; Reyes, Ashford; Ribbe, Joachim; Ringel, Maximilian; Ritschel, Markus; Rocha, Cesar B.; Rochetin, Nicolas; Hagen, Martin; Röttenbacher, Johannes; Rollo, Callum; Royer, Haley; Sadoulet, Pauline; Saffin, Leo; Sandiford, Sanola; Sandu, Irina; Schäfer, Michael; Schemann, Vera; Schirmacher, Imke; Hausold, Andrea; Schlenczek, Oliver; Schmidt, Jerome; Schröder, Marcel; Schwarzenboeck, Alfons; Sealy, Andrea; Senff, Christoph J.; Serikov, Ilya; Shohan, Samkeyat; Siddle, Elizabeth; Smirnov, Alexander; Heywood, Karen J.; Späth, Florian; Spooner, Branden; Stolla, M. Katharina; Szkółka, Wojciech; de Szoeke, Simon P.; Tarot, Stéphane; Tetoni, Eleni; Thompson, Elizabeth; Thomson, Jim; Tomassini, Lorenzo; Hirsch, Lutz; Totems, Julien; Ubele, Alma Anna; Villiger, Leonie; von Arx, Jan; Wagner, Thomas; Walther, Andi; Webber, Ben; Wendisch, Manfred; Whitehall, Shanice; Wiltshire, Anton; Jacob, Marek; Wing, Allison A.; Wirth, Martin; Wiskandt, Jonathan; Wolf, Kevin; Worbes, Ludwig; Wright, Ethan; Wulfmeyer, Volker; Young, Shanea; Zhang, Chidong; Zhang, Dongxiao; Jansen, Friedhelm; Ziemen, Florian; Zinner, Tobias; Zöger, Martin; Kinne, Stefan; Klocke, Daniel; Kölling, Tobias; Konow, Heike; Lothon, Marie; Mohr, Wiebke; Naumann, Ann Kristin; Nuijens, Louise; Olivier, Léa; Pincus, Robert; Pöhlker, Mira; Reverdin, Gilles; Roberts, Gregory; Schnitt, Sabrina; Schulz, Hauke; Siebesma, A. Pier; Stephan, Claudia Christine; Sullivan, Peter; Touzé-Peiffer, Ludovic; Vial, Jessica; Vogel, Raphaela; Zuidema, Paquita; Alexander, Nicola; Alves, Lyndon; Arixi, Sophian; Asmath, Hamish; Bagheri, Gholamhossein; Baier, Katharina; Bailey, Adriana; Baranowski, Dariusz; Baron, Alexandre; Barrau, Sébastien; Barrett, Paul A.; Batier, Frédéric; Behrendt, Andreas; Bendinger, Arne; Beucher, Florent; Bigorre, Sebastien; Blades, Edmund; Blossey, Peter; Bock, Olivier; Böing, Steven; Bosser, Pierre; Bourras, Denis; Bouruet-Aubertot, Pascale; Bower, Keith; Branellec, Pierre; Branger, Hubert; Brennek, Michal; Brewer, Alan; Brilouet, Pierre-Etienne; Brügmann, Björn; Buehler, Stefan A.; Burke, Elmo; Burton, Ralph; Calmer, Radiance; Canonici, Jean-Christophe; Carton, Xavier; Cato Jr., Gregory; Charles, Jude Andre; Chazette, Patrick; Chen, Yanxu; Chilinski, Michal T.; Choularton, Thomas; Chuang, Patrick; Clarke, Shamal; Coe, Hugh; Cornet, Céline; Coutris, Pierre; Couvreux, FleurThe science guiding the EUREC4A campaign and its measurements is presented. EUREC4A comprised roughly 5 weeks of measurements in the downstream winter trades of the North Atlantic – eastward and southeastward of Barbados. Through its ability to characterize processes operating across a wide range of scales, EUREC4A marked a turning point in our ability to observationally study factors influencing clouds in the trades, how they will respond to warming, and their link to other components of the earth system, such as upper-ocean processes or the life cycle of particulate matter. This characterization was made possible by thousands (2500) of sondes distributed to measure circulations on meso- (200 km) and larger (500 km) scales, roughly 400 h of flight time by four heavily instrumented research aircraft; four global-class research vessels; an advanced ground-based cloud observatory; scores of autonomous observing platforms operating in the upper ocean (nearly 10 000 profiles), lower atmosphere (continuous profiling), and along the air–sea interface; a network of water stable isotopologue measurements; targeted tasking of satellite remote sensing; and modeling with a new generation of weather and climate models. In addition to providing an outline of the novel measurements and their composition into a unified and coordinated campaign, the six distinct scientific facets that EUREC4A explored – from North Brazil Current rings to turbulence-induced clustering of cloud droplets and its influence on warm-rain formation – are presented along with an overview of EUREC4A's outreach activities, environmental impact, and guidelines for scientific practice. Track data for all platforms are standardized and accessible at https://doi.org/10.25326/165 (Stevens, 2021), and a film documenting the campaign is provided as a video supplement.